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AASHTO/AWS D1.5M/D1.5:2008An American National Standard

BridgeWelding Code

A Joint Publication of

American Association of State Highwayand Transportation Officials

second printing, June 2009second printing, June 2009

AASHTO/AWS D1.5M/D1.5:2008An American National Standard

Approved by theAmerican National Standards Institute

July 24, 2007

Bridge Welding Code

5th Edition

Supersedes AASHTO/AWS D1.5M/D1.5:2002

Prepared by theAmerican Welding Society (AWS) D1 Committee on Structural Welding

AASHTO Highway Subcommittee on Bridges and Structures

Under the Direction of theAWS Technical Activities Committee

AASHTO Executive Committee

Approved by theAWS Board of Directors

AASHTO Board of Directors/Policy Committee

AbstractThis code covers the welding requirements for AASHTO welded highway bridges made from carbon and low-alloyconstructional steels. This 2008 edition contains dimensions in metric SI Units and U.S. Customary Units. Clauses 1through 7 constitute a body of rules for the regulation of welding in steel construction. The provisions for Clause 9 havebeen distributed throughout the D1.5 code. Clauses 8, 10, and 11 do not contain provisions, as their analogue D1.1 sec-tions are not applicable to the D1.5 code. Clause 12 contains the requirements for fabricating fracture critical members.

A Joint Publication of:

American Association of State American Welding SocietyHighway and Transportation Officials 550 N.W. LeJeune Road

444 N. Capitol Street, N.W., Suite 225 Miami, FL 33126Washington, DC 20001

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AASHTO/AWS D1.5M/D1.5:2008

International Standard Book Number: 978-0-87171-075-8American Welding Society

550 N.W. LeJeune Road, Miami, FL 33126© 2008 by American Welding Society

All rights reservedPrinted in the United States of America

Errata: 2nd Printing, June 2009

Photocopy Rights. No portion of this standard may be reproduced, stored in a retrieval system, or transmitted in anyform, including mechanical, photocopying, recording, or otherwise, without the prior written permission of the copyrightowner.

Authorization to photocopy items for internal, personal, or educational classroom use only or the internal, personal, oreducational classroom use only of specific clients is granted by the American Welding Society provided that the appropriatefee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, tel: (978) 750-8400; Internet:<www.copyright.com>.

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Statement on the Use of American Welding Society Standards

All standards (codes, specifications, recommended practices, methods, classifications, and guides) of the AmericanWelding Society (AWS) are voluntary consensus standards that have been developed in accordance with the rules of theAmerican National Standards Institute (ANSI). When AWS American National Standards are either incorporated in, ormade part of, documents that are included in federal or state laws and regulations, or the regulations of other govern-mental bodies, their provisions carry the full legal authority of the statute. In such cases, any changes in those AWSstandards must be approved by the governmental body having statutory jurisdiction before they can become a part ofthose laws and regulations. In all cases, these standards carry the full legal authority of the contract or other documentthat invokes the AWS standards. Where this contractual relationship exists, changes in or deviations from requirementsof an AWS standard must be by agreement between the contracting parties.

AWS American National Standards are developed through a consensus standards development process that bringstogether volunteers representing varied viewpoints and interests to achieve consensus. While the AWS administers theprocess and establishes rules to promote fairness in the development of consensus, it does not independently test, evalu-ate, or verify the accuracy of any information or the soundness of any judgments contained in its standards.

AWS disclaims liability for any injury to persons or to property, or other damages of any nature whatsoever, whetherspecial, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, or relianceon this standard. AWS also makes no guarantee or warranty as to the accuracy or completeness of any informationpublished herein.

In issuing and making this standard available, AWS is neither undertaking to render professional or other services for oron behalf of any person or entity, nor is AWS undertaking to perform any duty owed by any person or entity to someoneelse. Anyone using these documents should rely on his or her own independent judgment or, as appropriate, seek theadvice of a competent professional in determining the exercise of reasonable care in any given circumstances. It isassumed that the use of this standard and its provisions are entrusted to appropriately qualified and competent personnel.

This standard may be superseded by the issuance of new editions. Users should ensure that they have the latest edition.

Publication of this standard does not authorize infringement of any patent or trade name. Users of this standard acceptany and all liabilities for infringement of any patent or trade name items. AWS disclaims liability for the infringement ofany patent or product trade name resulting from the use of this standard.

Finally, the AWS does not monitor, police, or enforce compliance with this standard, nor does it have the power to do so.

On occasion, text, tables, or figures are printed incorrectly, constituting errata. Such errata, when discovered, are postedon the AWS web page (www.aws.org).

Official interpretations of any of the technical requirements of this standard may only be obtained by sending a request,in writing, to the appropriate technical committee. Such requests should be addressed to the American Welding Society,Attention: Managing Director, Technical Services Division, 550 N.W. LeJeune Road, Miami, FL 33126 (see Annex M).With regard to technical inquiries made concerning AWS standards, oral opinions on AWS standards may be rendered.These opinions are offered solely as a convenience to users of this standard, and they do not constitute professionaladvice. Such opinions represent only the personal opinions of the particular individuals giving them. These individualsdo not speak on behalf of AWS, nor do these oral opinions constitute official or unofficial opinions or interpretations ofAWS. In addition, oral opinions are informal and should not be used as a substitute for an official interpretation.

This standard is subject to revision at any time by the AWS D1 Committee on Structural Welding and the AASHTOTechnical Committee on Welding. It must be reviewed every five years, and if not revised, it must be either reaffirmed orwithdrawn. Comments (recommendations, additions, or deletions) and any pertinent data that may be of use in improvingthis standard are required and should be addressed to AWS Headquarters. Such comments will receive careful considerationby the AWS D1 Committee on Structural Welding and the AASHTO Technical Committee on Welding and the author ofthe comments will be informed of the Committee’s response to the comments. Guests are invited to attend all meetingsof the AWS D1 Committee on Structural Welding and the AASHTO Technical Committee on Welding to express theircomments verbally. Procedures for appeal of an adverse decision concerning all such comments are provided in theRules of Operation of the Technical Activities Committee. A copy of these Rules can be obtained from the AmericanWelding Society, 550 N.W. LeJeune Road, Miami, FL 33126.

This page is intentionally blank.

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Personnel

AWS D1 Committee on Structural WeldingD. D. Rager, Chair Rager Consulting, Incorporated

D. K. Miller, 1st Vice Chair The Lincoln Electric CompanyA. W. Sindel, 2nd Vice Chair Alstorm Power

J. L. Gayler, Secretary American Welding SocietyN. J. Altebrando STV, Incorporated

F. G. Armao The Lincoln Electric CompanyE. L. Bickford Acute Technological Services

F. C. Breismeister Strocal, IncorporatedB. M. Butler Walt Disney World Company

H. H. Campbell III Technip USAL. E. Collins Team Industries, IncorporatedR. B. Corbit Exelon Nuclear Corporation

R. A. Dennis ConsultantM. A. Grieco Massachusetts Highway Department

C. R. Hess High Steel Structures, Incorporated (Retired)C. W. Holmes Modjeski and Masters, Incorporated

J. H. Kiefer ConocoPhillips CompanyV. Kuruvilla Genesis Quality Systems

J. Lawmon American Engineering & Manufacturing, IncorporatedD. R. Lawrence II Butler Manufacturing Company

D. R. Luciani Canadian Welding BureauS. L. Luckowski Department of the Army

P. W. Marshall MHP Systems EngineeringM. J. Mayes Mayes Testing Engineers, Incorporated

D. L. McQuaid D L McQuaid and Associates, IncorporatedR. D. Medlock High Steel Structures, Incorporated

J. Merrill MACTEC, IncorporatedT. L. Niemann Minnesota Department of TransportationD. C. Phillips Hobart Brothers Company

J. W. Post J. W. Post and Associates, IncorporatedT. J. Schlafly American Institute of Steel Construction

D. R. Scott PSID. A. Shapira Washington Group International

R. E. Shaw, Jr. Steel Structures Technology Center, IncorporatedR. W. Stieve Greenman-Pederson, IncorporatedP. J. Sullivan Massachusetts Highway Department (Retired)

M. M. Tayarani Massachusetts Turnpike AuthorityK. K. Verma Federal Highway AdministrationB. D. Wright Advantage Aviation Technologies

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*Deceased

Advisors to the AWS D1 Committee on Structural Welding

W. G. Alexander WGAPEE. M. Beck MACTEC, Incorporated

O. W. Blodgett The Lincoln Electric CompanyM. V. Davis Consultant

G. L. Fox Consultant*A. R. Fronduti Rex Fronduti and Associates

G. J. Hill G. J. Hill and Associates, IncorporatedM. L. Hoitomt Hoitomt Consulting Services

W. A. Milek, Jr. ConsultantJ. E. Myers Consultant

D. L. Sprow Consultant

AASHTO Technical Committee for Welding A. K. Bardow, Chair Massachusetts Highway Department

P. V. Liles, Vice Chair Georgia Department of Transportation G. Bailey West Virginia Department of Transportation

K. B. Carr Mississippi Department of Transportation D. L. Dorgan Minnesota Department of Transportation

N. L. MacDonald Iowa Department of Transportation B. Newton California Department of Transportation K. K. Verma Federal Highway Administration

Joint AASHTO/AWS Bridge Welding SubcommitteeT. L. Niemann, Chair Minnesota Department of Transportation

D. L. McQuaid, Vice Chair D L McQuaid and Associates, Incorporated

AASHTO RepresentativesS. J. Cook Michigan Department of Transportation

W. Doukas Maine Department of TransportationJ. J. Edwards Illinois Department of Transportation

Bureau of Bridges & StructuresJ. L. Ellerman Wyoming Department of TransportationH. E. Gilmer Texas Department of TransportationM. A. Grieco Massachusetts Highway Department

S. Walton North Carolina Department of Transportation

AWS RepresentativesC. R. Hess High Steel Structures, Incorporated

C. W. Holmes Modjeski & Masters, IncorporatedN. S. Lindell Inspectech Consulting and TestingD. K. Miller The Lincoln Electric Company

D. C. Phillips Hobart Brothers CompanyB. Roberds AFCO Steel

T. J. Shlafly AISCM. M. Tayarani Massachusetts Turnpike Authority

K. K. Verma Federal Highway Administration

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Advisors to the Joint AASHTO/AWS Bridge Welding Subcommittee

N. J. Altebrando STV, IncorporatedS. Camo Weidlinger Associates, Incorporated

L. E. Collins Team Industries, IncorporatedW. M. Kavicky Trans Bay Steel Corporation

S. W. Kopp High Steel StructuresR. D. Medlock High Steel Structures

J. Merrill Mactec Engineering & ConsultingN. P. Rimmer NYS Department of Transportation

R. Stieve Greenman-Pedersen, Incorporated


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Foreword

This foreword is not part of AASHTO/AWS D1.5M/D1.5:2008,Bridge Welding Code, but is included for informational purposes only.

The preparation of this specification was undertaken in response to a need for a common welding specification for thefabrication of steel highway bridges by welding. The departments of highways and transportation in the 50 states, theDistrict of Columbia, and Puerto Rico that make up the American Association of State Highway and Transportation Of-ficials have routinely used the specifications of the American Welding Society Structural Welding Committee, with appro-priate modifications, to produce contract documents suitable for the construction of bridges using Federal Highwayfunds. The proliferation of requirements by the 50 states, District of Columbia and Puerto Rico that make up AASHTO(American Association of State Highway and Transportation Officials) resulted in the recognition of the need for a singledocument that could produce greater economies in bridge fabrication, while at the same time addressing the issues ofstructural integrity and public safety.

The first AWS code for Fusion Welding and Gas Cutting in Building Construction was published in 1928. In 1934, acommittee was appointed to prepare specifications for the design, construction, alteration, and repair of highway andrailway bridges. The first bridge specification was published in 1936. Until 1963, there were separate AWS committeesfor bridges and buildings. These two committees joined in 1963 to form the Structural Welding Committee of theAmerican Welding Society. The committee has since promulgated standards for the application of welding to the designand construction of structures.

The Federal Highway Administration of the United States Department of Transportation requires states using federalfunds for the construction of welded highway bridges to conform to specified standards for design and construction.Conformance to the AWS Specification for Welded Highway and Railway Bridges was first specified in the third editionof the AASHTO Standard Specifications for Highway Bridges in 1941. In 1962, the Bureau of Public Roads, now theFederal Highway Administration (FHWA), required conformance to a Circular Memorandum, dated November 13,1962, which transmitted additional provisions for welding A36 steel pending publication of an AWS specification whichwould contain certain essential provisions not then in the code. Another Circular Memorandum, dated February 11,1965, specified requirements for CVN testing, and a further Circular Memorandum, dated August 19, 1966, modifiedprovisions of the 1966 Edition of the AWS D2.0-66, Specification for Welded Highway and Railway Bridges. An FHWAnotice, dated July 7, 1971, recommended that ultrasonic inspection not be used for final acceptance of welds made byelectrogas or electroslag procedures because of concern that the acceptance levels of AWS D2.0-69, Appendix C, werenot suitable to detect or reject piping porosity of major dimensions.

In 1974, AASHTO published the first edition of the Standard Specification for Welding of Structural Steel HighwayBridges. The Eleventh Edition of the AASHTO Standard Specifications for Highway Bridges, dated 1977, directed“Welding shall conform to the requirements of the AASHTO Standard Specifications for Welding of Structural SteelHighway Bridges 1974 and subsequent interim specifications…” AASHTO published the Second and Third editions ofthe Standard Specifications for Welding of Structural Steel Highway Bridges in 1977 and 1981. All of the AASHTOspecifications were required to be part of the Contract Documents as modifications or additions to the AWS StructuralWelding Code—Steel. This was a cumbersome procedure.

In 1982, a subcommittee was formed jointly by AASHTO and AWS, with equal representation from both organizations,to seek accommodation between the separate and distinct requirements of bridge Owners and existing provisions ofAWS D1.1. The Bridge Welding Code is the result of an agreement between AASHTO and AWS to produce a jointAASHTO/AWS Structural Welding Code for steel highway bridges that addresses essential AASHTO needs and makesAASHTO revisions mandatory.

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The 1988 version of the Bridge Welding Code provided for the qualification of welding procedures by test to assure thatweld had the strength, ductility, and toughness necessary for use in redundant structures. Nonredundant fracture criticalbridge members were not provided for in the first edition of the code. While qualification of welding procedures is re-quired, a major effort has been made to specify the minimum number of tests and the simplest tests that give reasonableassurance of required mechanical properties. Efforts are made to discourage individual States from requiring duplicationof weld testing unless that testing is specified in the bid documents. Special attention is directed to avoidance of unnec-essary hardening of base metal HAZs and the avoidance of hydrogen and other items that can lead to weld or base-metalcracking.

Consequently, while the D1.5-88 document has a superficial resemblance to D1.1 in its general format, there are signifi-cant differences that users should be aware of, among them the lack of provisions relating to statically loaded structures,tubular construction or the modification of existing structures. Users are encouraged to develop their own requirementsfor these applications or use existing documents (e.g., D1.1) with the appropriate modifications.

The publication of AASHTO/AWS D1.5M/D1.5:2008 was justified by the need to monitor, revise, and update codeprovisions based on the needs of AASHTO member states and industry. The following is a list of the major revisions in2008 edition:

(1) Addition of Commentary for Clauses 2, 3, 4, 5, 6, and Annex G.

(2) Deletion of material M270M [M270] Gr. 485W [70W] and inclusion of Gr. HPS 485W [HPS 70W].

(3) Addition of a new normative annex detailing welding requirements for M270M/M270 [A709M/A709] Gr. HPS485W [HPS 70W].

(4) Inclusion of HPS 50W materials.

(5) Addition of optional supplemental moisture-resistant designators.

(6) Machining and testing tolerances for performance test specimens.

(7) Additions and revisions to usage, handling, and storage requirements for consumables in fracture critical applications.

(8) Revisions to Tables 4.1, 4.2, 4.4, and 4.5.

(9) Addition of new filler metal variable in Table 5.3.

(10) Revision to inspection personnel qualification.

(11) Revised sample forms for WPSs and PQRs.

Changes in Code Requirements. Changes to the text of the 2008 edition are indicated by underlining. Changes toillustrations are highlighted by vertical lines in the margin.

Future revisions to this code will be made based on proposals from the Joint AASHTO/AWS Committee as well as thosefrom document users. It should be re-emphasized here that the Joint Committee is the primary agency for receiving feed-back from industry, and requires this input in order to produce a quality document. Other documents that do not receivethe ANSI/AASHTO/AWS accreditation should not be relied on as substitutes for the Joint Committee’s interpretation ofD1.5 provisions.

While the D1.1 and D1.5 codes do share a number of common provisions, it should not be assumed that revisions to onedocument provision automatically revises its analogous provision in the other; therefore, users are encouraged to treateach code as an independent document.

This code was prepared by the AASHTO/AWS Bridge Welding Committee operating as a Subcommittee of the AWSStructural Welding Committee. The Committee is made up of representatives from the AWS Structural Welding Com-mittee and the AASHTO Technical Committee for Welding. Accommodation was sought on all items where there wasdisagreement between AASHTO and AWS members. Specific issues considered essential by AASHTO were includedin this code to eliminate the need for supplemental exclusions or additions by AASHTO.

The AASHTO/AWS D1.5, Bridge Welding Code, will be subject to regular review by the Bridge Welding Committeeand will be republished or reaffirmed on an as-needed basis, at intervals not to exceed five years. All proposed changesto this code will be subject to approval by AWS and AASHTO prior to publication.

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Comments or inquiries pertaining to this code are welcome (see Annex M). They should be sent to the Secretary, AWSD1 Committee on Structural Welding, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126, or to theChairman of the AASHTO Technical Committee for Welding, American Association of State Highway and TransportationOfficials, 444 N. Capitol Street, N.W., Suite No. 225, Washington, DC 20001.

ErrataThe following Errata have been identified and incorporated into the current reprint of this document.

Page 89—Clause 5.10.2—Delete paragraph after the “Fillet Weld Properties” title so that no verbiage exists in the clause.

Page 262—Form L-3 Procedure Qualification Records (PQR) for Qualification, Pretest, and Verification Results—Change “Maximum Size Single Pass” to “Minimum Size Multiple Pass” under Macroetch row.

Page 319—Figure C-3.5 (A) & (B) Illustration of Camber Tolerances for Steel Beams—For sketches (A) & (B) the linedepicting the “Detailed Camber Shape” was corrected and made bolder than the line depicting “Actual Camber of theSteel” for additional clarity. Please see corrected figure below:

Figure C-3.5—Illustration of Camber Tolerances for Steel Beams


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Table of Contents

Page No.


Personnel ......................................................................................................................................................................vForeword .....................................................................................................................................................................ixList of Tables .......................................................................................................................................................... xviiiList of Figures............................................................................................................................................................xixList of Forms..............................................................................................................................................................xxi

1. General Provisions ............................................................................................................................................11.1 Application..............................................................................................................................................11.2 Base Metal ..............................................................................................................................................11.3 Welding Processes ..................................................................................................................................11.4 Fabricator Requirements.........................................................................................................................21.5 Definitions ..............................................................................................................................................21.6 Welding Symbols....................................................................................................................................21.7 Safety Precautions...................................................................................................................................21.8 Standard Units of Measurement .............................................................................................................21.9 Welding Procedure Specifications (WPSs) ............................................................................................31.10 Mechanical Testing.................................................................................................................................31.11 Reference Documents .............................................................................................................................3

2. Design of Welded Connections ........................................................................................................................5

Part A—General Requirements ..........................................................................................................................52.1 Drawings .................................................................................................................................................52.2 Basic Unit Stresses..................................................................................................................................62.3 Effective Weld Areas, Lengths, Throats, and Sizes ...............................................................................6

Part B—Structural Details ..................................................................................................................................62.4 General....................................................................................................................................................62.5 Welded Filler Plates................................................................................................................................62.6 PJP Groove Welds ..................................................................................................................................7

Part C—Details of Welded Joints .......................................................................................................................72.7 Joint Qualification...................................................................................................................................72.8 Details of Fillet Welds ............................................................................................................................72.9 Details of Plug and Slot Welds ...............................................................................................................72.10 Lap Joints ................................................................................................................................................82.11 Corner and T-Joints ................................................................................................................................82.12 CJP Groove Welds..................................................................................................................................82.13 PJP Groove Welds ..................................................................................................................................82.14 Prohibited Types of Joints and Welds ....................................................................................................92.15 Combinations of Welds ..........................................................................................................................92.16 Welds in Combination with Rivets and Bolts.........................................................................................92.17 Connection Details..................................................................................................................................9

3. Workmanship ..................................................................................................................................................513.1 General Requirements...........................................................................................................................513.2 Preparation of Base Metal.....................................................................................................................513.3 Assembly ..............................................................................................................................................54

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3.4 Control of Distortion and Shrinkage.....................................................................................................563.5 Dimensional Tolerances .......................................................................................................................563.6 Weld Profiles ........................................................................................................................................583.7 Repairs ..................................................................................................................................................583.8 Peening..................................................................................................................................................593.9 Caulking................................................................................................................................................603.10 Arc Strikes ............................................................................................................................................603.11 Weld Cleaning ......................................................................................................................................603.12 Weld Termination .................................................................................................................................603.13 Weld Backing .......................................................................................................................................60

4. Technique ........................................................................................................................................................65

Part A—General Requirements ........................................................................................................................654.1 Filler Metal Requirements ....................................................................................................................654.2 Preheat and Interpass Temperature Requirements................................................................................664.3 Heat Input Control for Grade 690 [100] and 690W [100W] ................................................................674.4 Stress Relief Heat Treatment ................................................................................................................67

Part B—Shielded Metal Arc Welding (SMAW) ..............................................................................................674.5 Electrodes for SMAW ..........................................................................................................................674.6 Procedures for SMAW..........................................................................................................................68

Part C—Submerged Arc Welding (SAW)........................................................................................................694.7 General Requirements...........................................................................................................................694.8 Electrodes and Fluxes for SAW............................................................................................................694.9 Procedures for SAW with a Single Electrode.......................................................................................704.10 Procedures for SAW with Parallel Electrodes ......................................................................................704.11 Procedures for SAW with Multiple Electrodes ....................................................................................71

Part D—Gas Metal Arc Welding (GMAW) and Flux Cored Arc Welding (FCAW) ......................................724.12 Electrodes..............................................................................................................................................724.13 Shielding Gas ........................................................................................................................................734.14 Procedures for GMAW and FCAW with a Single Electrode ...............................................................73

Part E—Electroslag Welding (ESW) and Electrogas Welding (EGW)............................................................734.15 Qualification of Process, WPSs, and Joint Details ...............................................................................734.16 Mechanical Properties...........................................................................................................................744.17 Condition of Electrodes and Guide Tubes ............................................................................................744.18 Shielding Gas ........................................................................................................................................744.19 Condition of Flux..................................................................................................................................744.20 Procedures for ESW and EGW.............................................................................................................74

Part F—Plug and Slot Welds ............................................................................................................................744.21 Plug Welds ............................................................................................................................................744.22 Slot Welds.............................................................................................................................................754.23 Plug and Slot Welds..............................................................................................................................75

Part G—Control of Production Welding Variables ..........................................................................................754.24 Tests ......................................................................................................................................................754.25 Control of Variables..............................................................................................................................754.26 Calibration of Equipment......................................................................................................................754.27 Current Control .....................................................................................................................................75

5. Qualification ....................................................................................................................................................855.0 Scope.....................................................................................................................................................85

Part A—Welding Procedure Specification (WPS) Qualification .....................................................................855.1 Approval ...............................................................................................................................................85

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5.2 Qualification Responsibility .................................................................................................................855.3 Duration ................................................................................................................................................855.4 Base Metal ............................................................................................................................................865.5 Welding Consumables ..........................................................................................................................875.6 Test Plate Thickness .............................................................................................................................875.7 General Requirements for WPS Qualification......................................................................................875.8 Position of Test Welds ..........................................................................................................................885.9 Options for WPS Qualification or Prequalification ..............................................................................895.10 Fillet Weld WPS Qualification .............................................................................................................895.11 Prequalified WPS..................................................................................................................................895.12 Heat Input WPS ....................................................................................................................................895.13 Production Procedure WPS ..................................................................................................................905.14 ESW and EGW .....................................................................................................................................915.15 Type of Tests and Purpose....................................................................................................................915.16 Weld Specimens—Number, Type, and Preparation .............................................................................915.17 Nondestructive Testing (NDT) .............................................................................................................925.18 Method of Testing Specimens ..............................................................................................................925.19 Test Results Required ...........................................................................................................................935.20 Retests ...................................................................................................................................................93

Part B—Welder, Welding Operator, and Tack Welder Qualification ..............................................................945.21 General Requirements...........................................................................................................................945.22 Production Welding Positions Qualified ..............................................................................................945.23 Qualification Tests Required ................................................................................................................955.24 Limitations of Variables .......................................................................................................................965.25 Test Specimens: Number, Type, and Preparation.................................................................................975.26 Method of Testing Specimens ..............................................................................................................975.27 Test Results Required ...........................................................................................................................985.28 Retests ...................................................................................................................................................99

6. Inspection.......................................................................................................................................................133

Part A—General Requirements ......................................................................................................................1336.1 General................................................................................................................................................1336.2 Inspection of Materials .......................................................................................................................1346.3 Inspection of WPS Qualification and Equipment...............................................................................1346.4 Inspection of Welder, Welding Operator, and Tack Welder Qualifications.......................................1346.5 Inspection of Work and Records ........................................................................................................1346.6 Obligations of the Contractor .............................................................................................................1356.7 Nondestructive Testing (NDT) ...........................................................................................................135

Part B—Radiographic Testing (RT) of Groove Welds in Butt Joints ............................................................1376.8 Extent of Testing.................................................................................................................................1376.9 General................................................................................................................................................1376.10 RT Procedure ......................................................................................................................................1376.11 Acceptability of Welds .......................................................................................................................1406.12 Examination, Report, and Disposition of Radiographs ......................................................................140

Part C—Ultrasonic Testing (UT) of Groove Welds .......................................................................................1406.13 General................................................................................................................................................1406.14 Extent of Testing.................................................................................................................................1406.15 UT Equipment.....................................................................................................................................1406.16 Reference Standards ...........................................................................................................................1416.17 Equipment Qualification.....................................................................................................................1416.18 Calibration for Testing........................................................................................................................1416.19 Testing Procedures..............................................................................................................................142

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6.20 Preparation and Disposition of Reports ..............................................................................................1436.21 Calibration of the UT Unit with IIW or Other Approved Reference Blocks .....................................1436.22 Equipment Qualification Procedures ..................................................................................................1446.23 Flaw Size Evaluation Procedures .......................................................................................................1466.24 Scanning Patterns................................................................................................................................1466.25 Examples of dB Accuracy Certification .............................................................................................146

Part D—Weld Acceptance Criteria.................................................................................................................1466.26 Quality of Welds .................................................................................................................................146

7. Stud Welding .................................................................................................................................................1677.1 Scope...................................................................................................................................................1677.2 General Requirements.........................................................................................................................1677.3 Mechanical Requirements...................................................................................................................1677.4 Workmanship......................................................................................................................................1687.5 Technique............................................................................................................................................1687.6 Stud Application Qualification Requirements ....................................................................................1697.7 Production Control..............................................................................................................................1707.8 Inspection Requirements.....................................................................................................................171

8. Statically Loaded Structures (No Applications within this code) ...............................................................175

9. Welded Steel Bridges (The provisions of this clause in ANSI/AASHTO/AWS [D1.5-96]were distributed throughout AASHTO/AWS [D1.5M/D1.5:2002]and remain so for this edition)..................................................................................177

10. Tubular Structures (No Applications within this code)...............................................................................179

11. Strengthening and Repairing Existing Structures (No Applications within this code) ............................181

12. AASHTO/AWS Fracture Control Plan (FCP) for Nonredundant Members .........................................18312.1 General Provisions ..............................................................................................................................18312.2 Definitions ..........................................................................................................................................18312.3 Contract Documents ...........................................................................................................................18312.4 Base Metal Requirements ...................................................................................................................18412.5 Welding Processes ..............................................................................................................................18412.6 Consumable Requirements .................................................................................................................18412.7 Welding Procedure Specification (WPS) ...........................................................................................18812.8 Certification and Qualification ...........................................................................................................18812.9 As-Received Inspection of Base Metal...............................................................................................18912.10 Thermal Cutting ..................................................................................................................................18912.11 Repair of Base Metal ..........................................................................................................................18912.12 Straightening, Curving, and Cambering .............................................................................................19012.13 Tack Welds and Temporary Welds ....................................................................................................19012.14 Preheat and Interpass Temperature Control........................................................................................19012.15 Postweld Thermal Treatments ............................................................................................................19012.16 Weld Inspection ..................................................................................................................................19112.17 Repair Welding ...................................................................................................................................192

Annexes.....................................................................................................................................................................197Cross Reference for Renumbered Annexes from the 2002 Code to the 2008 Code ................................................198Annex A (Normative)—Effective Throat ................................................................................................................199Annex B (Normative)—Effective Throats of Fillet Welds in Skewed T-Joints ......................................................201Annex C (Normative)—Flatness of Girder Webs—Bridges....................................................................................203Annex D (Normative)—Terms and Definitions.......................................................................................................209Annex E (Normative)—Manufacturer’s Stud Base Qualification Requirements ....................................................217

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Annex F (Normative)—Part A—Qualification and Calibration of the UT Unit with Other ApprovedAnnex F (Normative)—Reference Blocks ...............................................................................................................221Annex F (Normative)—Part B—UT Equipment Qualification Procedures.............................................................223Annex G (Normative)—Guidelines on Alternative Methods for Determining Preheat...........................................231Annex H (Normative)—Welding Requirements for Conventional, Nonfracture Critical M270M [M270]Annex H (Normative)—(A 709M [A 709]) HPS 485W [HPS 70W] Components with Reduced PreheatAnnex H (Normative)—and Interpass Temperature ................................................................................................241Annex I (Informative)—Weld Quality Requirements for Tension Joints................................................................243Annex J (Informative)—Description of Common Weld and Base Metal Discontinuities.......................................245Annex K (Informative)—Short Circuiting Transfer.................................................................................................255Annex L (Informative)—Suggested Sample Welding Forms ..................................................................................259Annex M (Informative)—Guidelines for Preparation of Technical Inquiries for the Joint AASHTO/AWSAnnex M (Informative)—Subcommittee on Bridge Welding..................................................................................267Annex N (Informative)—Reference Documents......................................................................................................269

Commentary on Bridge Welding Code.....................................................................................................................271Foreword...................................................................................................................................................................273

Index .........................................................................................................................................................................395

List of AWS Documents on Structural Welding......................................................................................................409

xviii

List of Tables

Table Page No.


2.1 Minimum Fillet Weld Size......................................................................................................................112.2 Minimum Effective Weld Size for PJP Groove Welds...........................................................................113.1 Limits on Acceptability and Repair of Cut Edge Discontinuities of Material ........................................623.2 Camber Tolerance for Typical Girder .....................................................................................................623.3 Camber Tolerance for Girders without a Designed Concrete Haunch....................................................624.1 Matching Filler Metal Requirements for WPSs Qualified in Conformance with 5.12...........................764.2 Matching Filler Metal Requirements for WPSs Qualified in Conformance with 5.13...........................794.3 Filler Metal Requirements for Exposed Bare Application of M270M [M270] (A709M [A709])

Gr. 345W [50W] and Gr. HPS 345W [HPS 50W] Steel.........................................................................824.4 Minimum Preheat and Interpass Temperature, °C [°F] ..........................................................................824.5 Minimum Holding Time .........................................................................................................................834.6 Alternate Stress-Relief Heat Treatment ..................................................................................................834.7 Allowable Atmospheric Exposure of Low-Hydrogen SMAW Electrodes .............................................835.1 WPS Qualification Requirements for Consumables .............................................................................1005.2 WPS Qualification or Prequalification Options ....................................................................................1005.3 PQR Essential Variable Changes for WPSs Qualified per 5.13.3 ........................................................1015.4 Additional PQR Essential Variable Changes Requiring WPS Requalification for ESW or EGW.......1045.5 Required Number of Test Specimens—WPS Qualification .................................................................1055.6 Welder Qualification—Type and Position Limitations ........................................................................1055.7 Number and Type of Specimens and Range of Thickness Qualified—Welder and Welding

Operator Qualification...........................................................................................................................1066.1 Hole-Type IQI Requirements................................................................................................................1496.1A Wire IQI Requirements .........................................................................................................................1496.2 Testing Angle ........................................................................................................................................1506.3 UT Acceptance-Rejection Criteria—Tensile Stress..............................................................................1526.4 UT Acceptance-Rejection Criteria—Compressive Stress.....................................................................1537.1 Mechanical Property Requirements for Studs.......................................................................................1727.2 Minimum Fillet Weld Size for Small Diameter Studs ..........................................................................17212.1 CVN Test Values of Weld Metal with Matching Strength ...................................................................19412.2 Tack Weld Requirements ......................................................................................................................19412.3 M270M [M270] (A709M [A709]) Gr. 250 [36], 345 [50] Minimum Preheat and Interpass

Temperatures, °C [°F] ...........................................................................................................................19512.4 M270M [M270] (A709M [A709]) Gr. 345W [50W], HPS 345W [HPS 50W], HPS 485W

[HPS 70W] Minimum Preheat and Interpass Temperatures, °C [°F] ...................................................19512.5 M270M [M270] (A709M [A709]) Gr. 690 [100], 690W [100W] Minimum and Maximum

Preheat/Interpass Temperatures, °C [°F]...............................................................................................195B.1 Equivalent Fillet Weld Leg Size Factors for Skewed T-Joints, R = 0 ..................................................202G.1 Susceptibility Index Grouping as Function of Hydrogen Level “H” and Composition

Parameter Pcm ........................................................................................................................................234G.2 Minimum Preheat and Interpass Temperatures for Three Levels of Restraint .....................................234H.1 Minimum Preheat and Interpass Temperature for M270M [M270] (A709M [A709])

HPS 485W [HPS 70W], °C [°F] ...........................................................................................................242H.2 Filler Metals for Use with the Reduced Preheat of Table H.1, Diffusible Hydrogen Levels

4 mL/100 g Maximum...........................................................................................................................242J.1 Common Types of Discontinuities........................................................................................................249K.1 Typical Current Ranges for Short Circuiting Transfer Gas Metal Arc Welding (GMAW-S) of Steel ....256

xix

List of Figures

Figure Page No.


2.1 Filler Plates Less Than 6 mm [1/4 in] Thick...........................................................................................122.2 Filler Plates 6 mm [1/4 in] or Thicker.....................................................................................................122.3 Details for Fillet Welds ...........................................................................................................................132.4 Details of Welded Joints for CJP Groove Welds ....................................................................................152.5 Details of Welded Joints for PJP Groove Welds.....................................................................................352.6 Fillet Welds on Opposite Sides of a Common Plane of Contact ............................................................472.7 Transition of Thickness at Butt Joints of Parts Having Unequal Thickness ...........................................482.8 Transition of Width at Butt Joints of Parts Having Unequal Width .......................................................493.1 Discontinuities in Cut Plate.....................................................................................................................633.2 Workmanship Tolerances in Assembly of Groove Welded Joints .........................................................633.3 Acceptable and Unacceptable Weld Profiles ..........................................................................................644.1 Weld Bead in Which Depth and Width Exceed the Width of the Weld Face.........................................845.1 WPS Qualification or Pretest—Test Plate A.........................................................................................1075.2 WPS Verification—Test Plate B...........................................................................................................1085.3 Weld Soundness Test Plate for Details Not Conforming to Figure 2.4 or 2.5—Test Plate C ..............1095.4 Positions of Fillet Welds .......................................................................................................................1115.5 Positions of Groove Welds....................................................................................................................1115.6 Position of Test Plates for Groove Welds .............................................................................................1125.7 Position of Test Plates for Fillet Welds.................................................................................................1135.8 Fillet Weld Soundness Test (Macroetch) for WPS Qualification—Test Plate D .................................1145.9 Standard Round All-Weld-Metal Tension Specimen............................................................................1155.10 Reduced Section Tension Specimen .....................................................................................................1155.11 Side-Bend Specimen .............................................................................................................................1165.12 Face- and Root-Bend Specimen............................................................................................................1165.13 CVN Test Specimen—Type A..............................................................................................................1175.14 Guided Bend Test Jig ............................................................................................................................1185.15 Alternative Wraparound Guided Bend Test Jig ....................................................................................1195.16 Alternative Roller-Equipped Guided Bend Test Jig for Bottom Ejection of

Test Specimen .......................................................................................................................................1205.17 Test Plate for Unlimited Thickness—Welder Qualification .................................................................1215.18 Optional Test Plate for Unlimited Thickness—Horizontal Position—Welder Qualification ................1225.19 Test Plate for Limited Thickness—All Positions—Welder Qualification............................................1235.20 Optional Test Plate for Limited Thickness—Horizontal Position—Welder Qualification ..................1235.21 Fillet-Weld-Break and Macroetch Test Plate—Welder Qualification—Option 1................................1245.22 Fillet Weld Root-Bend Test Plate—Welder Qualification—Option 2 .................................................1255.23 Plug Weld Macroetch Test Plate—Welder Qualification .....................................................................1265.24 Test Plate for Unlimited Thickness—Welding Operator Qualification................................................1275.25 Butt Joint for Welding Operator Qualification—ESW and EGW ........................................................1285.26 Fillet-Weld-Break and Macroetch Test Plate—Welding Operator Qualification—Option 1..................1295.27 Fillet Weld Root Bend Test Plate—Welding Operator Qualification—Option 2 ................................1305.28 Fillet-Weld-Break Specimen—Tack Welder Qualification..................................................................1315.29 Method of Rupturing Specimen—Tack Welder Qualification .............................................................1316.1A Radiographic Identification and Hole-Type or Wire IQI Locations on Approximately

Equal Thickness Joints 250 mm [10 in] and Greater in Length............................................................154

xx

Figure Page No.


6.1B Radiographic Identification and Hole-Type or Wire IQI Locations on ApproximatelyEqual Thickness Joints Less than 250 mm [10 in] in Length ...............................................................154

6.1C Radiographic Identification and Hole-Type or Wire IQI Locations onTransition Joints 250 mm [10 in] and Greater in Length......................................................................155

6.1D Radiographic Identification and Hole-Type or Wire IQI Locations onTransition Joints Less than 250 mm [10 in] in Length .........................................................................155

6.1E Hole-Type IQI Design...........................................................................................................................1566.1F Wire-Type IQI.......................................................................................................................................1576.2 RT Edge Block Placement ....................................................................................................................1586.3 Transducer Crystal ................................................................................................................................1596.4 Qualification Procedure of Search Unit Using IIW Reference Block ..................................................1596.5A International Institute of Welding (IIW) UT Reference Blocks ...........................................................1606.5B Other Approved UT Reference Blocks .................................................................................................1616.6 Transducer Positions (Typical) .............................................................................................................1636.7 Plan View of UT Scanning Patterns......................................................................................................1646.8 Weld Quality Requirements for Discontinuities Occurring in Tension Welds

(Limitations of Porosity and Fusion Discontinuities) ...........................................................................1656.9 Weld Requirements for Discontinuities Occurring in Compression Welds

(Limitations of Porosity or Fusion Type Discontinuities) ....................................................................1667.1 Dimension and Tolerances of Standard-Type Shear Connectors..........................................................1737.2 Typical Tension Test Fixture ................................................................................................................1737.3 Torque Testing Arrangement and Table of Testing Torques................................................................174E.1A Bend Testing Device .............................................................................................................................219E.1B Suggested Type of Device for Qualification Testing of Small Studs ...................................................219F.1 Example of the Use of Form F-1 UT Unit Certification .......................................................................224F.2 Example of Form F-2 ............................................................................................................................225F.3 Example of the Use of Form F-2...........................................................................................................226F.4 Example of Form F-3 ............................................................................................................................227F.5 Example of the Use of Form F-3...........................................................................................................228F.6 Form F-4—Report of UT of Welds.......................................................................................................229G.1 Zone Classification of Steels.................................................................................................................235G.2 Critical Cooling Rate for 350 HV and 400 HV.....................................................................................236G.3 Charts to Determine Cooling Rates for Single-Pass Submerged Arc Fillet Welds ................................237G.4 Relation Between Fillet Weld Size and Energy Input...........................................................................240J.1 Weld in Butt Joint .................................................................................................................................250J.2 Weld in Corner Joint .............................................................................................................................251J.3 Weld in T-Joint......................................................................................................................................252J.4 Weld in Lap Joint ..................................................................................................................................253J.5 Single-Pass Fillet Weld in T-Joint ........................................................................................................253J.6 Single-V-Groove Weld in Butt Joint.....................................................................................................254K.1 Oscillograms and Sketches of Short Circuiting Arc Metal Transfer ....................................................257

CommentaryC-2.1 Details of Alternative Groove Preparations for Corner Joint................................................................294C-3.1 Examples of Unacceptable Reentrant Corners......................................................................................317C-3.2 Examples of Good Practice for Cutting Copes .....................................................................................317C-3.3 Permissible Offset in Abutting Members..............................................................................................318C-3.4 Correction of Misaligned Members ......................................................................................................318C-3.5 Illustration of Camber Tolerances for Steel Beams ..............................................................................319C-3.6 Measurement of Flange Warpage and Tilt ............................................................................................320C-3.7 Tolerances Bearing Points.....................................................................................................................321

xxi

List of Forms

Form Page No.


L-1 Certificate of Conformance to Requirements for Welding Electrodes .................................................260L-2 Sample Welding Procedure Specification.............................................................................................261L-3 Procedure Qualification Record (PQR) for Qualification, Pretest, and Verification Results ...............262L-4 Procedure Qualification Record (PQR) Worksheet ..............................................................................263L-5 Welder and Welding Operator Qualification Record............................................................................264L-6 Report of Radiographic Examination of Welds ....................................................................................265L-7 Report of Magnetic Particle Examination of Welds .............................................................................266



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1

1.1 Application1.1.1 This code covers welding fabrication requirementsapplicable to welded highway bridges. It is to be used inconjunction with the AASHTO Standard Specificationfor Highway Bridges or the AASHTO LRFD BridgeDesign Specifications.

The code is not intended to be used for the following:

(1) Steels with a minimum specified yield strengthgreater than 690 MPa [100 ksi]

(2) Pressure vessels or pressure piping

(3) Base metals other than carbon or low alloy steels

(4) Structures composed of structural tubing

Fabrication of structures or components not specificallyaddressed by this code shall be performed in conform-ance with the special provisions of the contract or in con-formance with the written directives of the Engineer whomay choose to reference an alternate applicable weldingstandard.

1.1.2 The fundamental premise of the code is to providegeneral stipulations applicable to any routine bridge situa-tion. Acceptance criteria for production welds differentfrom those described in the code may be used for a partic-ular application, provided they are suitably documentedby the proposer and approved by the Engineer.

Such alternate acceptance criteria may be based uponevaluation of suitability for service using past experi-ence, experimental evidence, or engineering analysisconsidering material type, service load effects, and envi-ronmental factors.

1.1.3 The term Engineer as used in this code shall meanthe State Bridge Engineer, or the Bridge Engineer’s des-ignated representative. The Engineer acts on behalf ofthe State or Owner and unless otherwise specified, shallbe the Owner’s official representative. All references toacceptance or approval shall mean acceptance orapproval by the Engineer.

1.1.4 The term Contractor as used in this code indicatesthe party responsible for performing the work as requiredby the contract documents. The term Contractor is usedcollectively to mean contractor, manufacturer, fabricator,erector, or other party performing the work.

1.2 Base Metal1.2.1 Specified Base Metal. The contract documentsshall designate the specification and classification ofbase metals to be used.

1.2.2 Approved Base Metals. Unless otherwise specified,base metals to be welded under this code shall meet therequirements of the latest edition of AASHTO M270M[M270] (ASTM A 709M [A 709]) for the grade of steelshown on the plans or described in the specifications. AllGrade 345 (50) steel that is to be welded shall be Type 1, 2,or 3. Other steels may be approved by the Engineer. Thick-ness limitations shall not apply to bearing components.

M270M [M270] steels of a designated grade are essen-tially the same as ASTM A 709M [A 709] steels of thesame grade. The provisions of this code are not intendedfor use with steels having a minimum specified yieldstrength over 690 MPa [100 ksi].

1.2.3 Thickness Limitations. The provisions of thiscode do not apply to welding base metals less than 3 mm[1/8 in] thick. Where base metals thinner than 3 mm[1/8 in] are to be welded, the requirements of AWSD1.3/D1.3M, Structural Welding Code—Sheet Steel,should apply. When used in conjunction with AWSD1.3/D1.3M, the applicable provisions of this code shallbe observed.

1.3 Welding Processes1.3.1 Shielded metal arc welding (SMAW) WPSs (Weld-ing Procedure Specifications) which conform to the pro-visions of Clauses 2, 3, and 4, are operated within the

1. General Provisions

Bridge Welding Code

CLAUSE 1. GENERAL PROVISIONS AASHTO/AWS D1.5M/D1.5:2008

2

limitation of variables recommended by the manufac-turer, and which produce weld metal with a minimumspecified yield strength less than 620 MPa [90 ksi], shallbe deemed prequalified and exempt from the testsdescribed in Clause 5. WPSs for SAW, FCAW, GMAW,ESW, and EGW shall be qualified as described in 5.12 or5.13, as applicable.

1.3.2 Electroslag (ESW) and electrogas (EGW) weldingmay be used for groove welds in butt joints in com-pression members, provided the WPSs conform to theapplicable provisions of Clauses 2, 3, and 4, and theContractor qualifies them in conformance with therequirements of 5.13. ESW and EGW shall be subject toNDT, as described in Clause 6.

1.3.3 Stud welding may be used, provided the WPSsconform to the applicable provisions of Clause 7.

1.3.4 GMAW-S (short circuit arc) is not recommendedfor the construction of bridge members and shall not beused without written approval of the Engineer.

1.3.5 Other welding processes not described in this codemay be used if approved by the Engineer. These pro-cesses shall be qualified by the applicable tests describedin 5.13 and any other tests required by the Engineer. Inconjunction with the tests, the WPSs and limitation ofessential variables applicable to the specific welding pro-cess shall be established by the Contractor developingthe WPS. The range of essential variables shall be basedon documented evidence of experience with the process,or a series of tests shall be conducted to establish the lim-its of variables. Any change in essential variables outsidethe range so established shall require requalification.

1.3.6 Welding of Ancillary Products. Unless otherwiseprovided in the contract documents, ancillary products,such as drainage components, expansion dams, curb plates,bearings, hand rails, cofferdams, sheet piling, and otherproducts not subject to calculated tensile stress from liveload and not welded to main members in tension areas asdetermined by the Engineer, may be fabricated withoutperforming the WPS qualification tests described inClause 5, subject to the following restrictions:

(1) SMAW, SAW, FCAW, and GMAW WPSs shallbe considered prequalified and exempt from the qualifi-cation tests described in Clause 5, provided that weldingis performed in conformance with all other provisions ofthe code.

(2) All welding performed in conformance with thissubclause shall be conducted within the limitations ofwelding variables recommended by the filler metal man-ufacturer. Welds attaching ancillary products to mainmembers shall meet all requirements of the code, includ-ing WPS qualification testing.

(3) The Engineer shall be the final judge of whichproducts are considered ancillary and exempt from quali-fication tests.

1.4 Fabricator RequirementsFabricators shall be certified under the AISC QualityCertification Program, Simple Steel Bridges or MajorSteel Bridges, as required by the Engineer, or an equiva-lent program acceptable to the Engineer.

1.5 DefinitionsThe welding terms used in this code shall be interpretedin conformance with the definitions given in the latestedition of AWS A3.0, Standard Welding Terms andDefinitions, supplemented by Annex D of this code.

1.6 Welding SymbolsWelding symbols shall be those shown in the latest edi-tion of AWS A2.4, Standard Symbols for Welding, Braz-ing, and Nondestructive Examination. Special conditionsshall be fully explained by notes or details.

1.7 Safety PrecautionsThe technical document does not address all welding andhealth hazards. However, pertinent information can befound in the following documents:

(1) ANSI Z49.1, Safety in Welding, Cutting, andAllied Processes

(2) Manufacturer’s safety literature on equipment andmaterials

(3) Other pertinent documents as appropriate

These documents shall be referred to and followed asrequired.

NOTE: This code may involve hazardous materials, oper-ations, and equipment. The code does not purport toaddress all of the safety problems associated with its use.It is the responsibility of the user to establish appropriatesafety and health practices. The user should determine theapplicability of any regulatory limitations prior to use.

1.8 Standard Units of MeasurementThis standard makes use of both U.S. Customary Unitsand the International System of Units (SI). The measure-

AASHTO/AWS D1.5M/D1.5:2008 CLAUSE 1. GENERAL PROVISIONS

3

ments may not be exact equivalents; therefore, each sys-tem shall be used independently of the other withoutcombining in any way. The standard with the designationD1.5M:2008 uses SI Units. The standard designationD1.5:2008 uses U.S. Customary Units. The latter areshown within brackets [ ].

1.9 Welding Procedure Specifications (WPSs)

All production welding shall be performed in conform-ance with the provisions of an approved Welding Proce-dure Specification (WPS), which is based uponsuccessful test results as recorded in a Procedure Qualifi-cation Record (PQR) unless qualified in conformancewith 1.3.1. All WPSs shall reference the PQR that is thebasis for acceptance. A copy of the proposed WPS and

referenced PQR shall be submitted to the Engineer forapproval. Recommended forms for WPSs and PQRs areprovided in Annex D. WPSs for SMAW that meet therequirements of 5.11 shall be considered prequalifiedand exempt from qualification testing.

1.10 Mechanical TestingThe latest edition of AWS B4.0 or B4.0M, Standard forMechanical Testing of Welds, provides additional detailsof test specimen preparation and details of test fixtureconstruction.

1.11 Reference DocumentsSee Annex N for a description of the documents refer-enced in AASHTO/AWS D1.5M/D1.5:2008.


4



5

Part AGeneral Requirements

2.1 Drawings

2.1.1 Full and complete information regarding location,type, size, and extent of all welds shall be clearly shownon the drawings. The drawings shall clearly distinguishbetween shop and field welds. Unless specifically indi-cated in the design, all groove welds, both shop and field,shall be complete joint penetration (CJP) groove welds.

2.1.2 Those joints or groups of joints for which it is espe-cially important that the welding sequence and techniquebe carefully controlled to minimize shrinkage stressesand distortion shall be so noted on shop and workingdrawings.

2.1.3 Contract design drawings shall specify the effectiveweld length and, for partial joint penetration (PJP)groove welds, the required weld size, as defined in 2.3.Shop or working drawings shall specify the grooveangles (α and β) and depths (S) applicable for the weldsize (E) required for the welding processes and positionof welding to be used.

2.1.3.1 It is recommended that contract design draw-ings show CJP or PJP groove weld requirements. Thewelding symbol without dimensions designates a CJPweld, as follows:

The welding symbol with dimensions above or below thearrow designates a PJP weld, as follows:

2.1.3.2 Special groove details shall be specified whererequired.

2.1.4 Detail drawings shall clearly indicate by weldingsymbols or sketches the details of groove welded jointsand the preparation of material required to make them.Both width and thickness of steel backing shall bedetailed.

2.1.5 Any special inspection requirements shall be notedon the drawings or in the specifications.

2.1.6 Use of Undermatched Filler Metals. Under-matching filler metal may be used:

(1) For all fillet and PJP groove welds, when consis-tent with design requirements.

(2) For all CJP groove welds where the stress in theweld is tension or compression parallel to the weld axis,providing shear on the effective weld area meetsAASHTO design requirements for all applications.

For CJP groove welds in compression, undermatching upto 70 MPa [10 ksi] may be used. Weld sizes shall bebased on the strength of filler metal that is required to beused, or the strength of filler metal that may be used.Weld sizes and weld metal strength levels shall be inconformance with AASHTO Design Specifications.Design drawings shall show the weld size and, whererequired or allowed, the undermatching filler metalstrength classification shall be shown. Shop drawingsshall show the weld size and filler metal strength classifi-cation when undermatching filler metal is to be used.When no filler metal strength is shown, matching fillermetal shall be used.

2. Design of Welded Connections

CLAUSE 2. DESIGN OF WELDED CONNECTIONS AASHTO/AWS D1.5M/D1.5:2008

6

2.2 Basic Unit StressesBasic unit stresses for base metals and for effective areasof weld metal for application to AASHTO highwaybridges shall be as shown in the AASHTO StandardSpecifications for Highway Bridges or the AASHTOLRFD Bridge Design Specification.

2.3 Effective Weld Areas, Lengths, Throats, and Sizes

2.3.1 Groove Welds. The effective area shall be theeffective weld length multiplied by the effective grooveweld size.

2.3.1.1 The effective weld length for any grooveweld, square or skewed, shall be the width of the partjoined, perpendicular to the direction of stress.

2.3.1.2 The effective weld size of a CJP groove weldshall be the thickness of the thinner part joined. Noincrease is allowed for weld reinforcement.

2.3.1.3 The effective weld size of a PJP groove weldshall be the depth of bevel less 3 mm [1/8 in] for grooveshaving a groove angle less than 60° but not less than 45°at the root of the groove, when made by SMAW orSAW, when made in the vertical or overhead weldingpositions by GMAW or FCAW.

The effective weld size of a PJP groove weld shall be thedepth of bevel, without reduction, for grooves

(1) having a groove angle of 60° or greater at the rootof the groove when made by any of the following weld-ing processes: SMAW, SAW, GMAW, FCAW, EGW,or ESW, or

(2) having a groove angle not less than 45° at the rootof the groove when made in flat or horizontal positionsby GMAW or FCAW.

2.3.1.4 Flare groove joints shall not be used to joinstructural steel in bridges.

2.3.1.5 The minimum effective weld size of a PJPgroove weld shall be as described in Table 2.2.

2.3.2 Fillet Welds. The effective area shall be the effec-tive weld length multiplied by the effective throat. Stressin a fillet weld shall be considered as applied to thiseffective area, for any direction of applied load.

2.3.2.1 The effective length of a fillet weld shall bethe overall length of the full-size fillet, including boxing.No reduction in effective length shall be made for eitherthe start or crater of the weld if the weld is full sizethroughout its length.

2.3.2.2 The effective length of a curved fillet weldshall be measured along the centerline of the effectivethroat. If the weld area of a fillet weld in a hole or slotcomputed from this length is greater than the area foundfrom 2.3.3, then this latter area shall be used as the effec-tive area of the fillet weld.

2.3.2.3 The minimum effective length of a filletweld shall be at least four times the nominal size, or40 mm [1-1/2 in], whichever is greater.

2.3.2.4 The effective throat shall be the shortest dis-tance from the joint root to the weld face of the diagram-matic weld (see Annex A). NOTE: See Annex B formethod of calculating effective throats for fillet welds inskewed T-joints. A convenient tabulation of relative legsizes (W) for joints with zero root opening (R = 0) thatwill have the same strength as a 90° fillet weld has beenprovided for dihedral angles between 60° and 135° (seeAnnex B, Table B.1).

2.3.3 Plug and Slot Welds. The effective area of a plugor slot weld shall be the nominal area of the hole or slotin the plane of the faying surface.

2.3.4 The effective weld size of a combination PJPgroove weld and a fillet weld shall be the shortest dis-tance from the joint root to the weld face of the diagram-matic weld minus 3 mm [1/8 in], for any groove detailrequiring such deduction (see Annex B).

Part BStructural Details

2.4 GeneralWelded connections shall be designed and detailed tosatisfy the strength, stiffness, flexibility, and fatiguerequirements of the AASHTO and/or other applicabledesign specifications.

2.5 Welded Filler Plates2.5.1 Welded filler plates (see Figures 2.1 and 2.2) aredesignated Category E fatigue details and shall beavoided when joining tension and reversal of stressmembers. When the design allows the use of filler plates,they may be used in the following:

(1) Splicing parts of different thicknesses

(2) Connections that, due to existing geometric align-ment, shall accommodate offsets to allow simple framing

PARTS A & B

AASHTO/AWS D1.5M/D1.5:2008 CLAUSE 2. DESIGN OF WELDED CONNECTIONS

7

2.5.2 A filler plate less than 6 mm [1/4 in] thick shall notbe used to transfer stress but shall be kept flush with thewelded edges of the stress-carrying part. The sizes ofwelds along such edges shall be increased over therequired sizes by an amount equal to the thickness of thefiller plate (see Figure 2.1).

2.5.3 Any filler plate 6 mm [1/4 in] or more in thicknessshall extend beyond the edges of the splice plate or con-nection material. It shall be welded to the part on whichit is fitted, and the joint shall be of sufficient strength totransmit the splice plate or connection material stressapplied at the surface of the filler plate as an eccentricload. The welds joining the splice plate or connectionmaterial to the filler plate shall be sufficient to transmitthe splice plate or connection material stress and shall belong enough to avoid overstressing the filler plate alongthe toe of the weld (see Figure 2.2).

2.6 PJP Groove WeldsPJP groove welds shall not be used where the appliedtensile stress is normal to the effective throat of the weld.Joints containing PJP groove welds, made from one sideonly, shall be restrained to prevent rotation.

Part CDetails of Welded Joints

2.7 Joint QualificationDetails of welded joints that may be used in a prequali-fied WPS are described in 2.8 through 2.13.

2.7.1 Joint details may depart from the details describedin 2.9 and 2.10 only if the Contractor submits the pro-posed WPSs to the Engineer for approval, and at theContractor’s expense, demonstrates their adequacy inconformance with the requirements of 5.13 of this codeand their conformance with applicable provisions ofClauses 3, 4, and 5.

2.8 Details of Fillet Welds2.8.1 The details of fillet welds made by SMAW, SAW,GMAW, or FCAW to be used without WPS qualificationunder 5.13 are described in 2.8.1.1 through 2.8.1.5 anddetailed in Figure 2.3.

2.8.1.1 The minimum fillet weld size, except for filletwelds used to reinforce groove welds, shall be as shown

in Table 2.1, or as calculated using procedures estab-lished to prevent cracking in conformance with 4.2.1.1. Inboth cases, the minimum size shall apply if it is sufficientto satisfy design requirements.

2.8.1.2 The maximum fillet weld size detailed alongedges of material shall be the following:

(1) The thickness of the base metal, for metal lessthan 6 mm [1/4 in] thick (see Figure 2.3, Detail A).

(2) 2 mm [1/16 in] less than the thickness of basemetal, for metal 6 mm [1/4 in] or more in thickness (seeFigure 2.3, Detail B), unless the weld is designated onthe drawing to be built out to obtain full throat thickness.In the as-welded condition, the distance between theedge of the base metal and the toe of the weld may bemore or less than 2 mm [1/16 in], provided the weld sizeshall be clearly verifiable.

2.8.1.3 Fillet welds in holes or slots in lap joints maybe used to transfer shear or to prevent buckling or separa-tion of lapped parts. These fillet welds may overlap, sub-ject to the provisions of 2.3.2.2. Fillet welds in holes orslots are not to be considered as plug or slot welds.

2.8.1.4 Fillet welds may be used in skewed T-jointshaving a dihedral angle (Ψ) of not less than 60° nor morethan 135° (see Figure 2.3, Details C and D). Detail Dshall be used when Rn would exceed 5 mm [3/16 in]using Detail C.

2.8.1.5 When the design allows intermittent filletwelds, the minimum length of an intermittent fillet weldshall be as described in 2.3.2.3.

2.8.1.6 Minimum spacing and dimensions of holes orslots when fillet welding is used shall conform to therequirements of 2.9.

2.8.1.7 Fillet welds which support a tensile force thatis not parallel to the axis of the weld shall not terminateat the corners of parts or members, but shall be returnedcontinuously, full size, around the corner for a lengthequal to twice the weld size where such return can bemade in the same plane. Boxing shall be indicated ondesign and detail drawings.

2.8.1.8 Fillet welds deposited on the opposite sides ofa common plane of contact between two parts shall beinterrupted at a corner common to both welds (see Figure2.6).

2.9 Details of Plug and Slot Welds2.9.1 The details of plug and slot welds made by theSMAW, GMAW, or FCAW processes are described in2.9.2 through 2.9.7 and 3.3.1.

PARTS B & C


8

2.9.1.1 Plug and slot welds may be used without per-forming the WPS qualification described in 5.13, pro-vided the technique provisions of 4.21, 4.22, and 4.23, asapplicable, are met.

2.9.2 The minimum diameter of the hole for a plug weldshall be no less than the thickness of the part containingit plus 8 mm [5/16 in]. The maximum diameter shallequal the minimum diameter plus 3 mm [1/8 in] or 2-1/4times the thickness of the member, whichever is greater.

2.9.3 The minimum center-to-center spacing of plugwelds shall be four times the diameter of the hole.

2.9.4 The length of the slot for a slot weld shall notexceed ten times the thickness of the part containing it.The width of the slot shall be no less than the thicknessof the part containing it plus 8 mm [5/16 in]. The maxi-mum width shall equal the minimum width plus 3 mm[1/8 in] or 2-1/4 times the thickness of the member,whichever is greater.

2.9.5 The ends of the slot shall be semicircular or shallhave the corners rounded to a radius not less than thethickness of the part containing it, except those endswhich extend to the edge of the part.

2.9.6 The minimum spacing of lines of slot welds in adirection transverse to their length shall be four times thewidth of the slot. The minimum center-to-center spacingin a longitudinal direction on any line shall be two timesthe length of the slot.

2.9.7 The depth of filling of plug or slot welds in metal16 mm [5/8 in] thick or less shall be equal to the thick-ness of the material. In metal over 16 mm [5/8 in] thick,it shall be at least one-half the thickness of the material,but no less than 16 mm [5/8 in].

2.10 Lap Joints2.10.1 The minimum overlap of parts in stress-carryinglap joints shall be five times the thickness of the thinnerpart. Unless lateral deflection of the parts is prevented,they shall be connected by at least two transverse lines offillet, plug, or slot welds or by two or more longitudinalfillet or slot welds.

2.10.2 If longitudinal fillet welds are used alone in lapjoints of end connections, the length of each fillet weldshall be no less than the perpendicular distance betweenthe welds (shown as dotted line in Figure 2.6). The trans-verse spacing of the welds shall not exceed 16 times thethickness of the connected thinner part unless suitableprovision is made (as by intermediate plug or slot welds)to prevent buckling or separation of the parts. The longi-

tudinal fillet weld may be either at the edges of the mem-ber or in slots.

2.10.3 When fillet welds in holes or slots are used, theclear distance from the edge of the hole or slot to theadjacent edge of the part containing it, measured perpen-dicular to the direction of stress, shall be no less than fivetimes the thickness of the part nor less than two times thewidth of the hole or slot. The strength of the part shall bedetermined from the critical net section of the basemetal.

2.10.4 Lap joints are Category E details and should beavoided, when possible, in members subject to tension orreversal of stresses.

2.11 Corner and T-Joints

2.11.1 Corner and T-joints that are to be subjected tobending about an axis parallel to the joint shall have theirwelds arranged to avoid concentration of tensile stress atthe root of any weld.

2.11.2 Corner and T-joints parallel to the direction ofcomputed stress between components of built-up mem-bers designed for axial stress need not be CJP groovewelds. Fillet welds or a combination of PJP welds andreinforcing fillet welds may be used.

2.12 CJP Groove Welds

2.12.1 Dimensional Tolerances. Dimensions of groovewelds specified on design or detailed drawings may varyas shown in Figure 2.4.

2.12.2 Corner Joints. For corner joints using single-bevel groove welds, either plate may be bevelled, pro-vided the basic groove configuration is not changed andadequate edge distance is maintained to support thewelding operations without excessive melting. Jointpreparation that bevels the plate that will be stressed inthe short transverse direction will help to reduce lamellartearing.

2.13 PJP Groove Welds (see Figure 2.5)

2.13.1 Definition. Except as provided in Figure 2.4,groove welds without steel backing, welded from oneside, and groove welds welded from both sides but with-out backgouging, are considered PJP groove weldsunless qualified as CJPs by 5.7.7.

PART C


9

2.13.1.1 All PJP groove welds made by GMAW-Sshall be qualified by the WPS qualification testsdescribed in 5.13.

2.13.2 Minimum Effective Weld Size. The minimumeffective weld size of PJP square-, single-, or double-V-,bevel-, J-, and U-groove welds shall be as shown inTable 2.2.

Shop or working drawings shall specify the groovedepths (S) applicable for the effective weld size (E)required for the welding process and position of weldingto be used.

2.13.3 Corner Joints. For corner joints using single-bevel groove welds, either plate may be beveled, pro-vided the basic groove configuration is not changed andadequate edge distance is maintained to support thewelding operations without excessive melting. Jointpreparation that bevels the plate that will be stressed inthe short-transverse direction will help to reduce lamellartearing.

2.14 Prohibited Types of Joints and Welds

The joints and welds described in the following para-graphs shall be prohibited:

(1) All PJP groove welds in butt joints except thoseconforming to 2.17.3

(2) CJP groove welds, in all members carrying calcu-lated stress or in secondary members subject to tensionor the reversal of stress, made from one side only withoutany backing, or with backing other than steel, that hasnot been qualified in conformance with 5.13

(3) Intermittent groove welds

(4) Intermittent fillet welds, except as approved bythe Engineer

(5) Flat position bevel-groove and J-groove weldsin butt joints where V-groove and U-groove welds arepracticable

(6) Plug and slot welds in members subject to tensionand reversal of stress

2.15 Combinations of WeldsIf two or more of the general types of welds (groove, fil-let, plug, slot) are combined in a single joint, their allow-able capacity shall be computed with reference to theaxis of the group in order to determine the allowablecapacity of the combination (see Annex A). However,

such methods of adding individual capacities of welds donot apply to fillet welds reinforcing CJP groove welds.

2.16 Welds in Combination with Rivets and Bolts

In new work, rivets or bolts in combination with weldsshall not be considered as sharing the stress, and thewelds shall be provided to carry the entire stress forwhich the connection is designed. Bolts or rivets used inassembly may be left in place if their removal is notspecified. If bolts are to be removed, the plans shouldindicate whether holes should be filled and in whatmanner.

2.17 Connection Details2.17.1 Eccentricity of Connections

2.17.1.1 Eccentricity between intersecting parts andmembers shall be avoided insofar as practical.

2.17.1.2 In designing welded joints, adequate provi-sion shall be made for bending stresses due to eccentric-ity, if any, in the disposition and section of base metalparts and in the location and types of welded joints.

2.17.1.3 For members having symmetrical cross sec-tions, the connection welds shall be arranged symmetri-cally about the axis of the member, or proper allowanceshall be made for unsymmetrical distribution of stresses.

2.17.1.4 For axially stressed angle members, the cen-ter of gravity of the connecting welds shall preferably liebetween the line of the center of gravity of the angle’scross section and the centerline of the connected leg. Ifthe center of gravity of the connecting weld lies outsideof this zone, the total stresses, including those due to theeccentricity from the center of gravity of the angle, shallnot exceed those allowed by this code.

2.17.2 Connections or Splices—Tension and Com-pression Members. Connections or splices of tension orcompression members made by groove welds shall haveCJP groove welds. Connections or splices made with fil-let welds, except as noted in 2.17.3, shall be designed foran average of the calculated stress and the strength of themember, but not less than 75% of the strength of themember, or if there is repeated application of load, themaximum stress or stress range in such connection orsplice shall not exceed the fatigue stress allowed by theapplicable AASHTO specification.

2.17.3 Connections or Splices in Compression Mem-bers with Milled Joints. If members subject only to

PART C


10

compression are spliced and full-milled bearing is pro-vided, the splice material and its welding shall bearranged, unless otherwise stipulated by the applicablegeneral specifications, to hold all parts in alignment andshall be proportioned to carry 50% of the computedstress in the member. Where such members are in full-milled bearing on base plates, there shall be sufficientwelding to hold all parts securely in place.

2.17.4 Connections of Components of Built-Up Mem-bers. When a member is built up of two or more pieces,the pieces shall be connected along their longitudinaljoints by sufficient continuous welds to make the piecesact in unison.

2.17.5 Transition of Thicknesses or Widths at ButtJoints

2.17.5.1 Butt joints between parts having unequalthicknesses and subject to tensile stress shall have asmooth transition between the offset surfaces at a slopeof no more than 1 transverse to 2.5 longitudinal with thesurface of either part. The transition may be accom-plished by sloping weld surfaces, by chamfering thethicker part, or by a combination of the two methods (seeFigure 2.7).

2.17.5.2 In butt joints between parts of unequal thick-ness that are subject only to shear or compressive stress,transition of thickness shall be accomplished asdescribed in 2.17.5.1 when offset between surfaces ateither side of the joint is greater than the thickness of thethinner part connected. When the offset is equal to or lessthan the thickness of the thinner part connected, the faceof the weld shall be sloped no more than 1 transverse to2.5 longitudinal from the surface of the thinner part orshall be sloped to the surface of the thicker part if thisrequires a lesser slope with the following exception:Truss member joints and beam and girder flange joints

shall be made with smooth transitions of the typedescribed in 2.17.5.1.

2.17.5.3 Butt joints between parts having unequalwidth and subject to tensile stress shall have a smoothtransition between offset edges at a slope transition of nomore than 1 transverse to 2.5 longitudinal with the edgeof either part or shall be transitioned with a 600 mm[24 in] minimum radius tangent to the narrower part atthe center of the butt joint (see Figure 2.8). The stressrange for the transitional detail shall be as allowed byAASHTO design specifications.

2.17.6 Girders and Beams

2.17.6.1 Connections or splices in beams or girderswhen made by groove welds shall have CJP groovewelds. Connections or splices made with fillet or plugwelds shall be designed for the average of the calcu-lated stress and the strength of the member, but no lessthan 75 percent of the strength of member. When thereis repeated application of load, the maximum stressor stress range in such connections or splices shallnot exceed the fatigue stress allowed by the AASHTOspecification.

2.17.6.2 Splices between sections of rolled beams orbuilt-up girders shall preferably be made in a singletransverse plane. Shop splices of webs and flanges inbuilt-up girders, made before the webs and flanges arejoined to each other, may be located in a single trans-verse plane or multiple transverse planes, but the fatiguestress provisions of the AASHTO specifications shallapply.

2.17.6.3 Noncontinuous Beams. The connections atthe ends of noncontinuous beams shall be designed withflexibility so as to avoid excessive secondary stressesdue to bending. Seated connections with a flexible orguiding device to prevent end twisting are recommended.

PART C

11


Table 2.1Minimum Fillet Weld Sizea, b (see 2.8)

Base Metal Thickness of Thicker Part Joined (T) Minimum Size of Fillet Weld

T ≤ 20 mm [3/4 in]T > 20 mm [3/4 in]

6 mm [1/4 in]08 mm [5/16 in]

Single-pass welds shall be used

a Smaller fillet welds may be approved by the Engineer based upon applied stress and the use of appropriate preheat.b Except that the weld size need not exceed the thickness of the thinner part joined. For this exception, particular care should be taken to provide

sufficient preheat to ensure weld soundness.

Table 2.2Minimum Effective Weld Size for PJP Groove Weldsa, b (see 2.13.3)

Base Metal Thickness of Thicker Part Joined (T) Minimum Effective Weld Size

T ≤ 20 mm [3/4 in]T > 20 mm [3/4 in]

6 mm [1/4 in]08 mm [5/16 in]

a Smaller welds may be approved by the Engineer based upon applied stress and the use of appropriate preheat.b Except that the weld size need not exceed the thickness of the thinner part.

12


a The effective area of weld 2 shall equal that of weld 1, but its size shall be its effective size plus thethickness of the filler T.

Figure 2.1—Filler Plates Less Than 6 mm [1/4 in] Thick (see 2.5.1)

a The effective area of weld shall equal that of weld 1. The length of weld 2 shall be sufficient toavoid overstressing the filler plate in shear along planes x-x.

b The effective area of weld 3 shall at least equal that of weld 1 and there shall be no overstress ofthe ends of weld 3 resulting from the eccentricity of the forces acting on the filler plate.

Figure 2.2—Filler Plates 6 mm [1/4 in] or Thicker (see 2.5.3)

13


a Angles smaller than 60° are allowed; however, in such cases, the weld is considered to be a PJP groove weld.

Note: (E)(n), (E’)(n) = effective throats dependent on magnitude of root opening (Rn) (see 3.3.1). Subscript (n) represents 1, 2, 3, or 4.

Figure 2.3—Details for Fillet Welds (see 2.8.1)


14

Symbols for joint typesB — butt jointC — corner jointT — T-joint

BC — butt or corner jointTC — T- or corner joint

BTC — butt, T-, or corner joint

Symbols for base-metal thickness and penetrationL — limited thickness–CJPU — unlimited thickness–CJPP — PJP

Symbol for weld types1 — square-groove2 — single-V-groove3 — double-V-groove4 — single-bevel-groove5 — double-bevel-groove6 — single-U-groove7 — double-U-groove8 — single-J-groove9 — double-J-groove

Symbols for welding processes if not SMAWS — SAWG — GMAWF — FCAW

Welding processesSMAW — shielded metal arc weldingGMAW — gas metal arc weldingFCAW — flux cored metal arc welding

SAW — submerged arc welding

Welding positionsF — flatH — horizontalV — vertical

OH — overhead

DimensionsR — Root Opening

α, β — Groove Anglesf — Root Facer — J- or U-groove Radius

S, S1 , S2 — PJP Groove WeldDepth of Groove

E, E1 , E2 — PJP Groove WeldSizes corresponding to S, S1 , S2 , respectively

Joint DesignationThe lower case letters, e.g., a, b, c, etc., are used to differentiatebetween joints that would otherwise have the same jointdesignation.

Legend for Figures 2.4 and 2.5

Notes for Figures 2.4 and 2.5a Groove preparations detailed for SMAW joints may be used for GMAW or FCAW.b Joint shall be welded from one side only.c Backgouge root to sound metal before welding second side.d Minimum weld size (E) as shown in Table 2.2; S as specified on drawings.e Evidence of CJP shall be required (see 4.7.5).f Groove welds in corner and T-joints shall be reinforced with fillet welds with a leg size equal to or greater than T/4, but need not exceed

10 mm [3/8 in]. T shall be defined as the thinner of the attaching elements.g Double-groove welds may have grooves of unequal depth, but the depth of the shallower groove shall be no less than one-fourth of the

thickness of the thinner part joined.h Double-groove welds may have grooves of unequal depth, provided they conform to the limitations of Note d. Also the weld size (E),

less any reduction, applies individually to each groove.i The orientation of the two members in the joints may vary from 135° to 180° provided that the basic joint configuration (groove angle,

root face, root opening) remains the same and that the design weld size shall be maintained.j For corner and T-joints, the member orientation may be changed provided the groove angle shall be maintained as specified.k The member orientation may be changed provided that the groove dimensions shall be maintained as specified.l The orientation of the two members in the joints may vary from 45° to 135° for corner joints and from 45° to 90° for T-joints, provided that

the basic joint configuration (groove angle, root face, root opening) remains the same and that the design weld size shall be maintained.m These joint details shall not be used where V-groove or U-groove details are practicable (see 2.14).


15

See Notes on Page 14

Figure 2.4—Details of Welded Joints forCJP Groove Welds (see 2.12.1) (Dimensions in Millimeters)

Square-groove weld (1)Butt joint (B)Corner joint (C)

Welding Process

Joint Designation

Base Metal Thickness (U = unlimited)

Groove Preparation

Allowed Welding Positions

Gas Shielding for FCAW NotesRoot Opening

Tolerances

T1 T2

As Detailed(see 2.12.1)

As Fit-Up(see 3.3.4)

SMAWB-L1a 6 max. — R = T1 +2, –0 +6, –2 All — a, i

C-L1a 6 max. U R = T1s +2, –0 +6, –2 All — aFCAWGMAW B-L1a-GF 10 max. — R = T1 +2, –0 +6, –2 All Not

required i

Square-groove weld (1)Butt joint (B)

Welding Process

Joint Designation


Groove Preparation



Tolerances

T1 T2



SMAW B-L1b 6 max. — R = +2, –0 +2, –3 All — a, c, i

GMAWFCAW B-L1b-GF 10 max. — R = 0 to 3 +2, –0 +2, –3 All Not

required c, i

SAW B-L1-S 10 max. — R = 0 ±0 +2, –0 F — e, iSAW B-L1a-S 16 max. — R = 0 ±0 +2, –0 F — c, i

T1

2------


16


Figure 2.4 (Continued)—Details of Welded Joints forCJP Groove Welds (see 2.12.1) (Dimensions in Millimeters)

Single-V-groove weld (2)Corner joint (C)

Welding Process

Joint Designation


Groove Preparation


Gas Shielding for FCAW Notes

Root OpeningRoot Face

Groove Angle

Tolerances

T1 T2



SMAW C-U2 U UR = 0 to 3f = 0 to 3α = 60°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited+10°, –5°

All — a, c, f, l

GMAWFCAW C-U2-GF U U

R = 0 to 3f = 0 to 3α = 60°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited+10°, –5°

All Not required c, f, l

SAW C-U2b-S 25 min. UR = 0

f = 6 max.α = 60°

±0+6, –0

+10°, –0°

+2, –0±2

+10°, –5°F — c, f, l

Double-V-groove weld (3)Butt joint (B)

For B-U3c-S only

T1 S1

Over to50 60 3560 80 4580 90 5590 100 60

100 120 70120 140 80140 160 95

For T1 > 160 or T1 ≤ 50S1 = 2/3 (T1 – 6)

Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW B-U3bU —

R = 0 to 3f = 0 to 3

α = β = 60°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited+10°, –5°

All — a, c, g, iGMAWFCAW B-U3-GF All Not

required c, g, i

SAW B-U3c-S U —

R = 0f = 6 min.

α = β = 60°

+2, –0+6, –0

+10°, –0°

+2, –0+6, –0

+10°, –5° F — c, g, i

To find S1 see table above: S2 = T1 – (S1 + f)


17




Tolerances



R = +2, –0 +6, –2a = +10°, –0° +10°, –5°

Welding Process

Joint Designation

Base Metal Thickness (U = unlimited) Groove Preparation Allowed

Welding Positions

Gas Shielding for FCAW NotesT1 T2 Root Opening Groove Angle

SMAW C-U2a U UR = 6 α = 45° All — a, lR = 10 α = 30° F, V, OH — a, lR = 12 α = 20° F, V, OH — a, l

GMAWFCAW C-U2a-GF U U

R = 5 α = 30° F, V, OH Required lR = 10 α = 30° F, V, OH Not req. lR = 6 α = 45° F, V, OH Not req. l

SAW C-L2a-S 50 max. U R = 6 α = 30° F — lSAW C-U2-S U U R = 16 α = 20° F — l

Single-V-groove weld (2)Butt joint (B)

Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW B-U2 U —R = 0 to 3f = 0 to 3α = 60°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited+10°, –5°

All — a, c, i

GMAWFCAW B-U2-GF U —

R = 0 to 3f = 0 to 3α = 60°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited+10°, –5°

All Not required c, i

SAW B-L2c-S

Over 12to 25 —

R = 0f = 6 min.α = 60°

R = ±0f = +6, –0

α = +10°, –0°

+2, –0Not limited+10°, –5°

F — c, iOver 25to 38 —

R = 0f = 10 min.

α = 60°

Over 38to 50 —

R = 0f = 12 min.

α = 60°

α


18



Square-groove weld (1)T-joint (T)Corner joint (C)

Welding Process

Joint Designation


Groove Preparation



Tolerances

T1 T2



SMAW TC-L1b 6 max. U R = +2, –0 +2, –3 All — a, c, f

GMAWFCAW TC-L1-GF 10 max. U R = 0 to 3 +2, –0 +2, –3 All Not

required c, f

SAW TC-L1-S 10 max. U R = 0 ±0 +2, –0 F — c, f


Tolerances



R = +2, –0 +6, –2α = +10°, –0° +10°, –5°

Welding Process

Joint Designation


Welding Positions


SMAW B-U2a U —R = 6 α = 45° All — a, iR = 10 α = 30° F, V, OH — a, iR = 12 α = 20° F, V, OH — a, i

GMAWFCAW B-U2a-GF U —

R = 5 α = 30° F, V, OH Required iR = 10 α = 30° F, V, OH Not req. iR = 6 α = 45° F, V, OH Not req. i

SAW B-L2a-S 50 max. — R = 6 α = 30° F — iSAW B-U2-S U — R = 16 α = 20° F — i

T1

2------

α


19



Tolerances



R = +2, –0 +6, –2a = +10°, –0° +10°, –5°

Welding Process

Joint Designation


Welding Positions


SMAW B-U4a U —R = 6 α = 45° F, H — a, i, m

R = 10 α = 30° F, H — a, i, m


R = 5 α = 30° H Required iR = 6 α = 45° H Not req. iR = 10 α = 30° H Not req. i

Tolerances



R = +2, –0 +6, –2α = +10°, –0° +10°, –5°

Welding Process

Joint Designation


Welding Positions


SMAW TC-U4c U UR = 6 α = 45° All — a, lR = 10 α = 30° F, OH, H — a, l

GMAWFCAW TC-U4c-GF U U

R = 5 α = 30° All Required lR = 10 α = 30° F Not req. lR = 6 α = 45° All Not req. l

SAW TC-U4a-S U UR = 10 α = 30°

F — lR = 6 α = 45°

Single-bevel-groove weld (4)Butt joint (B)

Single-bevel-groove weld (4)T-joint (T)Corner joint (C)


20




Welding Process

Joint Designation


Groove Preparation



Tolerances

T1 T2



SMAW B-U4b U — R = 0 to 3f = 0 to 3α = 45°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited

10°, –5°

F, H — a, c, i, m

GMAWFCAW B-U4b-GF U — H Not

required c, i


Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW TC-U4b U U R = 0 to 3f = 0 to 3α = 45°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited

10°, –5°

All — a, c, f, lGMAWFCAW TC-U4b-GF U U All Not

required c, f, l

SAW TC-U4b-S U UR = 0

f = 3 max.α = 60°

±0+0, –3

+10°, –0°

+6, –0±2

10°, –5°F — c, f, l




21



Double-bevel-groove weld (5)Butt joint (B)

Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW B-U5a U —

R = 0 to 3f = 0 to 3α = 45°

β = 0° to 15°

+2, –0+2, –0

+2, –3Not limited

F, H — a, c, g, i, m


R = 0 to 3f = 0 to 3α = 45°

β = 0° to 15°

+2, –0+2, –0α + β =

+10°, –0°

+2, –3Not limited

α + β =+10°, –5°

H Not required c, g, i

Double-bevel-groove weld (5)T-joint (T)Corner joint (C)

Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW TC-U5b U U R = 0 to 3f = 0 to 3α = 45°

+2, –0+2, –0

+10°, –0°

+2, –3Not limited+10°, –5°

All — a, c, f, g, l

GMAWFCAW TC-U5-GF U U All Not

required c, f, g, l

SAW TC-U5-S U UR = 0

f = 5 max.α = 60°

±0+0, –5

+10°, –0°

+2, –0±2

+10°, –5°F — c, f, g, l

β

α α

α β+10° –0°

+ α β+10° –5°

+




22



Single-U-groove weld (6)Butt joint (B)Corner joint (C)

Tolerances



R = +2, –0 +2, –3α = +10°, –0° +10°, –5°

f = ±2 Not Limitedr = +3, –0 +3, –0

Welding Process

Joint Designation

Base Metal Thickness (U = unlimited) Groove Preparation


Gas Shielding for FCAW NotesT1 T2 Root Opening

Groove Angle

RootFace

Groove Radius

SMAWB-U6 U U

R = 0 to 3 α = 45° f = 3 r = 6 All — a, c, iR = 0 to 3 α = 20° f = 3 r = 6 F, OH — a, c, i

C-U6 U UR = 0 to 3 α = 45° f = 3 r = 6 All — a, c, lR = 0 to 3 α = 20° f = 3 r = 6 F, OH — a, c, l

GMAWFCAW

B-U6-GF U U R = 0 to 3 α = 20° f = 3 r = 6 All Not req. c, iC-U6-GF U U R = 0 to 3 α = 20° f = 3 r = 6 All Not req. c, l

SAWB-U6-S 16 min. 16 min. R = 0 α = 20° f = 6 min. r = 6 F — c, iC-U6-S 16 min. 16 min. R = 0 α = 20° f = 6 min. r = 6 F — c, l

Double-U-groove weld (7)Butt joint (B)

Tolerances



For B-U7 and B-U7-GFR = +2, –0 +2, –3

α = +10°, –0° +10°, –5°f = ±2, –0 Not Limitedr = +6, –0 ±2

For B-U7-SR = ±0 +2, –0

f = +0, –6 ±2

Welding Process

Joint Designation



Gas Shielding for FCAW NotesT1 T2

RootOpening

Groove Angle

RootFace

Groove Radius

SMAW B-U7 U —R = 0 to 3 α = 45° f = 3 r = 6 All — a, c, g, iR = 0 to 3 α = 20° f = 3 r = 6 F, OH — a, c, g, i

GMAWFCAW B-U7-GF U — R = 0 to 3 α = 20° f = 3 r = 6 All Not

required c, g, i

SAW B-U7-S U — R = 0 α = 20° f = 6 max. r = 6 F — c, g, i

α

α


23



Tolerances



R = +2, –0 +2, –3α = +10°, –0° +10°, –5°

f = +2, –0 Not Limitedr = +6, –0 ±2

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW B-U8 U — R = 0 to 3 α = 45° f = 3 r = 10 F, H — a, c, i, m

GMAWFCAW B-U8-GF U — R = 0 to 3 α = 30° f = 3 r = 10 H Not

required c, i

Single-J-groove weld (8)T-joint (T)Corner joint (C)

Tolerances



R = +2, –0 +2, –3α = +10°, –0° +10°, –5°

f = +2, –0 Not Limitedr = +6, –0 ±2

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW TC-U8a U UR = 0 to 3 α = 45° f = 3 r = 10 All — a, c, f, i

R = 0 to 3 α = 30° f = 3 r = 10 F, OH — a, c, f, i

GMAWFCAW TC-U8a-GF U U R = 0 to 3 α = 30° f = 3 r = 10 All Not

required c, f, i

SAW TC-U8a-S 16 min. 16 min. R = 0 α = 30° f = 6 min. r = 10 F — c, f, i

Single-J-groove weld (8)Butt joint (B)


24



Tolerances



R = +2, –0 +2, –3α = +10°, –0° +10°, –5°

f = +2, –0 Not Limitedr = +3, –0 ±2

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW B-U9 U — R = 0 to 3 α = 45° f = 3 r = 10 F, H — a, c, g, i, m

GMAWFCAW B-U9-GF U — R = 0 to 3 α = 30° f = 3 r = 10 H Not

required c, g, i

Double-J-groove weld (9)T-joint (T)Corner joint (C)

Tolerances



R = +2, –0 +2, –3α = +10°, –0° +10°, –5°

f = +2, –0 Not Limitedr = +3, –0 ±2

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW TC-U9a U UR = 0 to 3 α = 45° f = 3 r = 10 All — a, c, f, g,

lR = 0 to 3 α = 30° f = 3 r = 10 F, OH — c, f, g, l

GMAWFCAW TC-U9a-GF U U R = 0 to 3 α = 30° f = 3 r = 10 All Not

required c, f, g, l

SAW TC-U9a-S 10 min. 10 min. R = 0 α = 30° f = 6 r = 10 F — c, f, g, l

Double-J-groove weld (9)Butt joint (B)


25


Figure 2.4 (Continued)—Details of Welded Joints forCJP Groove Welds (see 2.12.1) (Dimensions in Inches)

Square-groove weld (1)Butt joint (B)Corner joint (C)

Welding Process

Joint Designation


Groove Preparation



Tolerances

T1 T2



SMAWB-L1a 1/4 max. — R = T1 +1/16, –0 +1/4, –1/16 All — a, i

C-L1a 1/4 max. U R = T1 +1/16, –0 +1/4, –1/16 All — iFCAWGMAW B-L1a-GF 3/8 max. — R = T1 +1/16, –0 +1/4, –1/16 All Not

required i


Welding Process

Joint Designation


Groove Preparation



Tolerances

T1 T2



SMAW B-L1b 1/4 max. — R = +1/16, –0 +1/16, –1/8 All — a, c, i

GMAWFCAW B-L1b-GF 3/8 max. — R = 0 to 1/8 +1/16, –0 +1/16, –1/8 All Not

required c, i

SAW B-L1-S 3/8 max. — R = 0 ±0 +1/16, –0 F — e, iSAW B-L1a-S 5/8 max. — R = 0 ±0 +1/16, –0 F — c, i

T1

2------


26




Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW C-U2 U UR = 0 to 1/8f = 0 to 1/8

α = 60°

+1/16, –0+1/16, –0+10°, –0°

+1/16, –1/8Not limited+10°, –5°

All — a, c, f, l

GMAWFCAW C-U2-GF U U

R = 0 to 1/8f = 0 to 1/8

α = 60°

+1/16, –0+1/16, –0+10°, –0°

+1/16, –1/8Not limited+10°, –5°

All Not required c, f, l

SAW C-U2b-S 1 min. UR = 0

f = 1/4 max.α = 60°

±0+1/4, –0+10°, –0°

+1/16, –0±1/16

+10°, –5°F — c, f, l


For B-U3c-S only

T1 S1

Over to2 2-1/2 1-3/8

2-1/2 3 1-3/43 3-5/8 2-1/8

3-5/8 4 2-1/24 4-3/4 2-3/4

4-3/4 5-1/2 35-1/2 6-1/4 3-3/4

For T1 > 6-1/4 or T1 ≤ 2S1 = 2/3 (T1 – 1/4)

Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW B-U3bU —

R = 0 to 1/8f = 0 to 1/8α = β = 60°

+1/16, –0+1/16, –0+10°, –0°

+1/16, –1/8Not limited+10°, –5°

All — a, c, g, iGMAWFCAW B-U3-GF All Not

required c, g, i

SAW B-U3c-S U —

R = 0f = 1/4 min.α = β = 60°

+1/16, –0+1/4, –0+10°, –0°

+1/16, –0+1/4, –0+10°, –5° F — c, g, i

To find S1 see table above: S2 = T1 – (S1 + f)


27




Tolerances



R = +1/16, –0 +1/4, –1/16a = +10°, –0° +10°, –5°

Welding Process

Joint Designation


Welding Positions


SMAW C-U2a U UR = 1/4 α = 45° All — a, lR = 3/8 α = 30° F, V, OH — a, lR = 1/2 α = 20° F, V, OH — a, l

GMAWFCAW C-U2a-GF U U

R = 3/16 α = 30° F, V, OH Required lR = 3/8 α = 30° F, V, OH Not req. lR = 1/4 α = 45° F, V, OH Not req. l

SAW C-L2a-S 2 max. U R = 1/4 α = 30° F — lSAW C-U2-S U U R = 5/8 α = 20° F — l


Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW B-U2 U —R = 0 to 1/8f = 0 to 1/8

α = 60°

+1/16, –0+1/16, –0+10°, –0°

+1/16, –1/8Not limited+10°, –5°

All — a, c, i


R = 0 to 1/8f = 0 to 1/8

α = 60°

+1/16, –0+1/16, –0+10°, –0°

+1/16, –1/8Not limited+10°, –5°

All Not required c, i

SAW B-L2c-S

Over 1/2to 1 —

R = 0f = 1/4 min.

α = 60°R = ±0

f = +1/4, –0α = +10°, –0°

+1/16, –0Not limited+10°, –5°

F — c, iOver 1to 1-1/2 —

R = 0f = 3/8 min.

α = 60°

Over 1-1/2to 2 —

R = 0f = 1/2 min.

α = 60°

α


28



Square-groove weld (1)T-joint (T)Corner joint (C)

Welding Process

Joint Designation


Groove Preparation



Tolerances

T1 T2



SMAW TC-L1b 1/4 max. U R = +1/16, –0 +1/16, –1/8 All — a, c, f

GMAWFCAW TC-L1-GF 3/8 max. U R = 0 to 1/8 +1/16, –0 +1/16, –1/8 All Not

required c, f

SAW TC-L1-S 3/8 max. U R = 0 ±0 +1/16, –0 F — c, f


Tolerances



R = +1/16, –0 +1/4, –1/16α = +10°, –0° +10°, –5°

Welding Process

Joint Designation


Welding Positions


SMAW B-U2a U —R = 1/4 α = 45° All — a, iR = 3/8 α = 30° F, V, OH — a, iR = 1/2 α = 20° F, V, OH — a, i


R = 3/16 α = 30° F, V, OH Required iR = 3/8 α = 30° F, V, OH Not req. iR = 1/4 α = 45° F, V, OH Not req. i

SAW B-L2a-S 2 max. — R = 1/4 α = 30° F — iSAW B-U2-S U — R = 5/8 α = 20° F — i

T1

2------

α


29



Tolerances



R = +1/16, –0 +1/4, –1/16a = +10°, –0° +10°, –5°

Welding Process

Joint Designation


Welding Positions


SMAW B-U4a U —R = 1/4 α = 45° F, H — a, i, m

R = 3/8 α = 30° F, H — a, i, m


R = 3/16 α = 30° H Required iR = 1/4 α = 45° H Not req. iR = 3/8 α = 30° H Not req. i

Tolerances



R = +1/16, –0 +1/4, –1/16α = +10°, –0° +10°, –5°

Welding Process

Joint Designation


Welding Positions


SMAW TC-U4c U UR = 1/4 α = 45° All — a, lR = 3/8 α = 30° F, OH, H — a, l

GMAWFCAW TC-U4c-GF U U

R = 3/16 α = 30° All Required lR = 3/8 α = 30° F Not req. lR = 1/4 α = 45° All Not req. l

SAW TC-U4a-S U UR = 3/8 α = 30°

F — lR = 1/4 α = 45°




30




Welding Process

Joint Designation


Groove Preparation



Tolerances

T1 T2



SMAW B-U4b U — R = 0 to 1/8f = 0 to 1/8

α = 45°

+1/16, –0+1/16, –0+10°, –0°

+1/16, –1/8Not limited

10°, –5°

F, H — a, c, i, m

GMAWFCAW B-U4b-GF U — H Not

required c, i


Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW TC-U4b U U R = 0 to 1/8f = 0 to 1/8

α = 45°

+1/16, –0+1/16, –0+10°, –0°


10°, –5°

All — a, c, f, lGMAWFCAW TC-U4b-GF U U All Not

required c, f, l

SAW TC-U4b-S U UR = 0

f = 1/8 max.α = 60°

±0+0, –1/8+10°, –0°

+1/4, –0±1/16

10°, –5°F — c, f, l




31




Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW B-U5a U —

R = 0 to 1/8f = 0 to 1/8

α = 45°β = 0° to 15°

+1/16, –0+1/16, –0


F, H — a, c, g, i, m


R = 0 to 1/8f = 0 to 1/8

α = 45°β = 0° to 15°

+1/16, –0+1/16, –0

α + β =+10°, –0°


α + β =+10°, –5°

H Not required c, g, i


Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW TC-U5b U U R = 0 to 1/8f = 0 to 1/8

α = 45°

+1/16, –0+1/16, –0+10°, –0°

+1/16, –1/8Not limited+10°, –5°

All — a, c, f, g, l

GMAWFCAW TC-U5-GF U U All Not

required c, f, g, l

SAW TC-U5-S U UR = 0

f = 3/16 max.α = 60°

±0+0, –3/16+10°, –0°

+1/16, –0±1/16

+10°, –5°F — c, f, g, l

β

α α

α β+10° –0°

+ α β+10° –5°

+




32



Single-U-groove weld (6)Butt joint (B)Corner joint (C)

Tolerances



R = +1/16, –0 +1/16, –1/8α = +10°, –0° +10°, –5°

f = ±1/16 Not Limitedr = +1/8, –0 +1/8, –0

Welding Process

Joint Designation



Gas Shielding for FCAW NotesT1 T2 Root Opening

Groove Angle

RootFace

Groove Radius

SMAWB-U6 U U

R = 0 to 1/8 α = 45° f = 1/8 r = 1/4 All — a, c, iR = 0 to 1/8 α = 20° f = 1/8 r = 1/4 F, OH — a, c, i

C-U6 U UR = 0 to 1/8 α = 45° f = 1/8 r = 1/4 All — a, c, lR = 0 to 1/8 α = 20° f = 1/8 r = 1/4 F, OH — a, c, l

GMAWFCAW

B-U6-GF U U R = 0 to 1/8 α = 20° f = 1/8 r = 1/4 All Not req. c, iC-U6-GF U U R = 0 to 1/8 α = 20° f = 1/8 r = 1/4 All Not req. c, l

SAWB-U6-S 5/8 min. 5/8 min. R = 0 α = 20° f = 1/4

min. r = 1/4 F — c, i

C-U6-S 5/8 min. 5/8 min. R = 0 α = 20° f = 1/4 min. r = 1/4 F — c, l

Double-U-groove weld (7)Butt joint (B)

Tolerances



For B-U7 and B-U7-GFR = +1/16, –0 +1/16, –1/8α = +10°, –0° +10°, –5°f = ±1/16, –0 Not Limitedr = +1/4, –0 ±1/16

For B-U7-SR = ±0 +1/16, –0

f = +0, –1/4 ±1/16

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW B-U7 U —R = 0 to 1/8 α = 45° f = 1/8 r = 1/4 All — a, c, g, iR = 0 to 1/8 α = 20° f = 1/8 r = 1/4 F, OH — a, c, g, i

GMAWFCAW B-U7-GF U — R = 0 to 1/8 α = 20° f = 1/8 r = 1/4 All Not

required c, g, i

SAW B-U7-S U — R = 0 α = 20° f = 1/4 max. r = 1/4 F — c, g, i

α

α


33



Tolerances



R = +1/16, –0 +1/16, –1/8α = +10°, –0° +10°, –5°f = +1/16, –0 Not Limitedr = +1/4, –0 ±1/16

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW B-U8 U — R = 0 to 1/8 α = 45° f = 1/8 r = 3/8 F, H — a, c, i, m

GMAWFCAW B-U8-GF U — R = 0 to 1/8 α = 30° f = 1/8 r = 3/8 H Not

required c, i


Tolerances



R = +1/16, –0 +1/16, –1/8α = +10°, –0° +10°, –5°f = +1/16, –0 Not Limitedr = +1/4, –0 ±1/16

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW TC-U8a U UR = 0 to 1/8 α = 45° f = 1/8 r = 3/8 All — a, c, f, i

R = 0 to 1/8 α = 30° f = 1/8 r = 3/8 F, OH — a, c, f, i

GMAWFCAW TC-U8a-GF U U R = 0 to 1/8 α = 30° f = 1/8 r = 3/8 All Not

required c, f, i

SAW TC-U8a-S 5/8 min. 5/8 min. R = 0 α = 30° f = 1/4 min. r = 3/8 F — c, f, i

Single-J-groove weld (8)Butt joint (B)


34



Tolerances



R = +1/16, –0 +1/16, –1/8α = +10°, –0° +10°, –5°f = +1/16, –0 Not Limitedr = +1/8, –0 ±1/16

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW B-U9 U — R = 0 to 1/8 α = 45° f = 1/8 r = 3/8 F, H — a, c, g, i, m

GMAWFCAW B-U9-GF U — R = 0 to 1/8 α = 30° f = 1/8 r = 3/8 H Not

required c, g, i


Tolerances



R = +1/16, –0 +1/16, –1/8α = +10°, –0° +10°, –5°f = +1/16, –0 Not Limitedr = +1/8, –0 ±1/16

Welding Process

Joint Designation




RootOpening

Groove Angle

RootFace

Groove Radius

SMAW TC-U9a U UR = 0 to 1/8 α = 45° f = 1/8 r = 3/8 All — a, c, f, g,

lR = 0 to 1/8 α = 30° f = 1/8 r = 3/8 F, OH — c, f, g, l

GMAWFCAW TC-U9a-GF U U R = 0 to 1/8 α = 30° f = 1/8 r = 3/8 All Not

required c, f, g, l

SAW TC-U9a-S 3/8 min. 3/8 min. R = 0 α = 30° f = 1/4 r = 3/8 F — c, f, g, l

Double-J-groove weld (9)Butt joint (B)


35


Figure 2.5—Details of Welded Joints forPJP Groove Welds (see 2.13.1) (Dimensions in Millimeters)


Welding Process

Joint Designation


Groove Preparation


Weld Size(E) NotesRoot Opening

Tolerances

T1 T2



SMAW

B-P1a 3 max. — R = 0 to 2 +2, –0 ±2 All T1 – 1 a, b

B-P1c 6 max. — R = min. +2, –0 ±2 All a, b


E1 + E2 MUST NOT EXCEED

FOR BUTT JOINT RESTRICTIONS, SEE 2.14

Welding Process

Joint Designation


Groove Preparation


Total Weld Size(E1 + E2) NotesRoot Opening

Tolerances

T1 T2



SMAW B-P1b 6 max. — R = +2, –0 ±2 All a

T1

2------

T1

2------

3T1

4---------

T1

2------

3T1

4----------



36


‡Fit-up tolerance, see 3.3.2, for rolled shapes R may be 8 mm in thick plates if backing is provided.

Figure 2.5 (Continued)—Details of Welded Joints forPJP Groove Welds (see 2.13.1) (Dimensions in Millimeters)


FOR BUTT JOINT RESTRICTIONS,SEE 2.14

Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes


Groove Angle

Tolerances

T1 T2



SMAW C-P2 6 min. UR = 0

f = 1 min.α = 60°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All S a, b, d, k

GMAWFCAW C-P2-GF 6 min. U

R = 0f = 3 min.α = 60°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All S b, d, k

SAW C-P2-S 11 min. UR = 0

f = 6 min.α = 60°

±0Unlimited+10°, –0°

+2, –0‡

±2+10°, –5°

F S b, d, k



Welding Process

Joint Designation


Groove Preparation


TotalWeld Size(E1 + E2) Notes


Groove Angle

Tolerances

T1 T2



SMAW B-P3 12 min. —R = 0

f = 3 min.α = 60°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All S1 + S2

a, d, h, k

GMAWFCAW B-P3-GF 12 min. —

R = 0f = 3 min.α = 60°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All S1 + S2 d, h, k

SAW B-P3-S 20 min. —R = 0

f = 6 min.α = 60°


+2, –0±2

+10°, –5°F S1 + S2 d, h, k

αα

αα

α

α


37





Single-bevel-groove (4)T-joint (T)Corner joint (C)

FOR CORNER AND T-JOINTRESTRICTIONS, SEE 2.11


Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes


Groove Angle

Tolerances

T1 T2



SMAW TC-P4 U UR = 0

f = 3 min.α = 45°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All S–3 a, b, d, f,

k

GMAWFCAW TC-P4-GF 6 min. U

R = 0f = 3 min.α = 45°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All S–3 b, d, f, k

SAW TC-P4-S 11 min. UR = 0

f = 6 min.α = 60°


+2, –0‡

±2+10°, –5°

F S b, d, f, k




Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW TC-P5 8 min. UR = 0

f = 3 min.α = 45°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All

(S1 + S2)–6

a, d, f, h, k


R = 0f = 3 min.α = 45°

+2, –0Unlimited+10°, –0°

+3, –2±2

+10°, –5°All

(S1 + S2)–6

d, f, h, k

SAW TC-P5-S 20 min. UR = 0

f = 6 min.α = 60°


+2, –0±2

+10°, –5°F S1 + S2 d, f, h, k


38




Single-U-groove weld (6)Corner joint (C)



Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes


Groove RadiusGroove Angle

Tolerances

T1 T2



SMAW C-P6 6 min. U

R = 0f = 1 min.

r = 6α = 45°

+2, –0+U, –0+6, –0

+10°, –0°

+3, –2±2±2

+10°, –5°

All S a, b, d, k

GMAWFCAW C-P6-GF 6 min. U

R = 0f = 3 min.

r = 6α = 20°

+2, –0+U, –0+6, –0

+10°, –0°

+3, –2±2±2

+10°, –5°

All S b, d, k

SAW C-P6-S 11 min. U

R = 0f = 6 min.

r = 6α = 20°

±0+U, –0+6, –0

+10°, –0°

+2, –0‡

±2±2

+10°, –5°

F S b, d, k

α

α


39






Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes



Tolerances

T1 T2



SMAW TC-P8 6 min. U

R = 0f = 3 min.

r = 10α = 45°

+2, –0Not limited

+6, –0+10°, –0°

+3, –2±2±2

+10°, –5°

All S a, d, f, k

SMAW C-P8* 6 min. U

R = 0f = 3 min.

r = 10α = 30°

+2, –0Not limited

+6, –0+10°, –0°

+3, –2±2±2

+10°, –5°

All S a, d, f, k


R = 0f = 3 min.

r = 10α = 45°

+2, –0Not limited

+6, –0+10°, –0°

+3, –2±2±2

+10°, –5°

All S d, f, k

GMAWFCAW C-P8-GF* 6 min. U

R = 0f = 3 min.

r = 10α = 30°

+2, –0Not limited

+6, –0+10°, –0°

+3, –2±2±2

+10°, –5°

All S d, f, k

SAW TC-P8-S 11 min. U

R = 0f = 6 min.

r = 12α = 45°

±0Not limited

+6, –0+10°, –0°

+2, –0‡

±2±2

+10°, –5°

F S d, f, k

SAW C-P8-S* 11 min. U

R = 0f = 6 min.

r = 12α = 30°

±0Not limited

+6, –0+10°, –0°

+2, –0‡

±2±2

+10°, –5°

F S d, f, k

‡Fit-up tolerance, see 3.3.2, for rolled shapes R may be 8 mm in thick plates if backing is provided.*Applies to outside corner joints.


40






Welding Process

Joint Designation


Groove Preparation





Tolerances

T1 T2



SMAW TC-P9 12 min. U

R = 0f = 3 min.

r = 10α = 45°

+2, –0–0

+6, –0+10°, –0°

+3, –2±2±2

+10°, –5°

All S1 + S2a, d, f,

h, k

GMAWFCAW TC-P9-GF* 12 min. U

R = 0f = 3 min.

r = 10α = 30°

+2, –0Not limited

+6, –0+10°, –0°

+3, –2±2±2

+10°, –5°

All S1 + S2 d, f, h, k

SAW C-P9-S 20 min. U

R = 0f = 6 min.

r = 12α = 45°

±0Not limited

+6, –0+10°, –0°

+2, –0±2±2

+10°, –5°

F S1 + S2 d, f, h, k

SAW C-P9-S* 20 min. U

R = 0f = 6 min.

r = 12α = 20°

±0Not limited

+6, –0+10°, –0°

+2, –0‡

±2±2

+10°, –5°

F S1 + S2 d, f, h, k

SAW T-P9-S 20 min. U

R = 0f = 6 min.

r = 12α = 45°

±0Not limited

+6, –0+10°, –0°

+2, –0‡

±2±2

+10°, –5°

F S1 + S2 d, f, h, k

‡Fit-up tolerance, see 3.3.2, for rolled shapes R may be 8 mm in thick plates if backing is provided.*Applies to outside corner joints.


41


Figure 2.5 (Continued)—Details of Welded Joints forPJP Groove Welds (see 2.13.1) (Dimensions in Inches)


Welding Process

Joint Designation


Groove Preparation


Weld Size(E) NotesRoot Opening

Tolerances

T1 T2



SMAW

B-P1a 1/8 max. — R = 0 to 1/16 +1/16, –0 ±1/16 All T1 – 1/32 a, b

B-P1c 1/4 max. — R = min. +1/16, –0 ±1/16 All a, b


E1 + E2 MUST NOT EXCEED


Welding Process

Joint Designation


Groove Preparation


Total Weld Size(E1 + E2) NotesRoot Opening

Tolerances

T1 T2



SMAW B-P1b 1/4 max. — R = +1/16, –0 ±1/16 All a

T1

2------

T1

2------

3T1

4---------

T1

2------

3T1

4----------



42


‡Fit-up tolerance, see 3.3.2, for rolled shapes R may be 5/16 in in thick plates if backing is provided.




Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes


Groove Angle

Tolerances

T1 T2



SMAW C-P2 1/4 min. UR = 0

f = 1/32 min.α = 60°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All S a, b, d, k

GMAWFCAW C-P2-GF 1/4 min. U

R = 0f = 1/8 min.

α = 60°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All S b, d, k

SAW C-P2-S 7/16 min. UR = 0

f = 1/4 min.α = 60°


+1/16, –0‡

±1/16+10°, –5°

F S b, d, k



Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW B-P3 1/2 min. —R = 0

f = 1/8 min.α = 60°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All S1 + S2

a, d, h, k

GMAWFCAW B-P3-GF 1/2 min. —

R = 0f = 1/8 min.

α = 60°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All S1 + S2 d, h, k

SAW B-P3-S 3/4 min. —R = 0

f = 1/4 min.α = 60°


+1/16, –0±1/16

+10°, –5°F S1 + S2 d, h, k

αα

αα

α

α


43





Single-bevel-groove (4)T-joint (T)Corner joint (C)



Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes


Groove Angle

Tolerances

T1 T2



SMAW TC-P4 U UR = 0

f = 1/8 min.α = 45°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All S–1/8 a, b, d, f,

k

GMAWFCAW TC-P4-GF 1/4 min. U

R = 0f = 1/8 min.

α = 45°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All S–1/8 b, d, f, k

SAW TC-P4-S 7/16 min. UR = 0

f = 1/4 min.α = 60°


+1/16, –0‡

±1/16+10°, –5°

F S b, d, f, k




Welding Process

Joint Designation


Groove Preparation




Groove Angle

Tolerances

T1 T2



SMAW TC-P5 5/16 min. UR = 0

f = 1/8 min.α = 45°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All

(S1 + S2)–1/4

a, d, f, h, k


R = 0f = 1/8 min.

α = 45°

+1/16, –0Unlimited+10°, –0°

+1/8, –1/16±1/16

+10°, –5°All

(S1 + S2)–1/4

d, f, h, k

SAW TC-P5-S 3/4 min. UR = 0

f = 1/4 min.α = 60°


+1/16, –0±1/16

+10°, –5°F S1 + S2 d, f, h, k


44




Single-U-groove weld (6)Corner joint (C)



Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes



Tolerances

T1 T2



SMAW C-P6 1/4 min. U

R = 0f = 1/32 min.

r = 1/4α = 45°

+1/16, –0+U, –0

+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S a, b, d, k

GMAWFCAW C-P6-GF 1/4 min. U

R = 0f = 1/8 min.

r = 1/4α = 20°

+1/16, –0+U, –0

+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S b, d, k

SAW C-P6-S 7/16 min. U

R = 0f = 1/4 min.

r = 1/4α = 20°

±0+U, –0

+1/4, –0+10°, –0°

+1/16, –0‡

±1/16±1/16

+10°, –5°

F S b, d, k

α

α


45






Welding Process

Joint Designation


Groove Preparation


Weld Size(E) Notes



Tolerances

T1 T2



SMAW TC-P8 1/4 min. U

R = 0f = 1/8 min.

r = 3/8α = 45°

+1/16, –0Not limited+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S a, d, f, k

SMAW C-P8* 1/4 min. U

R = 0f = 1/8 min.

r = 3/8α = 30°

+1/16, –0Not limited+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S a, d, f, k


R = 0f = 1/8 min.

r = 3/8α = 45°

+1/16, –0Not limited+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S d, f, k

GMAWFCAW C-P8-GF* 1/4 min. U

R = 0f = 1/8 min.

r = 3/8α = 30°

+1/16, –0Not limited+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S d, f, k

SAW TC-P8-S 7/16 min. U

R = 0f = 1/4 min.

r = 1/2α = 45°

±0Not limited+1/4, –0+10°, –0°

+1/16, –0‡

±1/16±1/16

+10°, –5°

F S d, f, k

SAW C-P8-S* 7/16 min. U

R = 0f = 1/4 min.

r = 1/2α = 30°

±0Not limited+1/4, –0+10°, –0°

+1/16, –0‡

±1/16±1/16

+10°, –5°

F S d, f, k

‡Fit-up tolerance, see 3.3.2, for rolled shapes R may be 5/16 in in thick plates if backing is provided.*Applies to outside corner joints.


46






Welding Process

Joint Designation


Groove Preparation





Tolerances

T1 T2



SMAW TC-P9 1/2 min. U

R = 0f = 1/8 min.

r = 3/8α = 45°

+1/16, –0–0

+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S1 + S2a, d, f,

h, k

GMAWFCAW TC-P9-GF* 1/2 min. U

R = 0f = 1/8 min.

r = 3/8α = 30°

+1/16, –0Not limited+1/4, –0+10°, –0°

+1/8, –1/16±1/16±1/16

+10°, –5°

All S1 + S2 d, f, h, k

SAW C-P9-S 3/4 min. U

R = 0f = 1/4 min.

r = 1/2α = 45°

±0Not limited+1/4, –0+10°, –0°

+1/16, –0±1/16±1/16

+10°, –5°

F S1 + S2 d, f, h, k

SAW C-P9-S* 3/4 min. U

R = 0f = 1/4 min.

r = 1/2α = 20°

±0Not limited+1/4, –0+10°, –0°

+1/16, –0‡

±1/16±1/16

+10°, –5°

F S1 + S2 d, f, h, k

SAW T-P9-S 3/4 min. U

R = 0f = 1/4 min.

r = 1/2α = 45°

±0Not limited+1/4, –0+10°, –0°

+1/16, –0‡

±1/16±1/16

+10°, –5°

F S1 + S2 d, f, h, k

‡Fit-up tolerance, see 3.3.2, for rolled shapes R may be 5/16 in in thick plates if backing is provided.*Applies to outside corner joints.


47

Figure 2.6—Fillet Welds on Opposite Sides of a Common Plane of Contact (see 2.8.1.8)


48

Notes:1. Groove may be of any allowed or qualified type and detail.2. Transition slopes shown are the maximum allowed.

Figure 2.7—Transition of Thickness at Butt Joints ofParts Having Unequal Thickness (see 2.17.5.1)


49

Figure 2.8—Transition of Width at Butt Joints of PartsHaving Unequal Width (see 2.17.5.3)



50


51

3.1 General Requirements3.1.1 All applicable paragraphs of this section shall beobserved in the fabrication of welded bridges under thiscode.

3.1.2 All welding and thermal-cutting equipment shall beso designed and manufactured, and shall be in such con-dition, as to enable designated personnel to follow theprocedures and attain the results described elsewhere inthe code.

3.1.3 Welding shall not be done when the ambient tem-perature is lower than –20°C [0°F] (see 4.2), when sur-faces are wet or exposed to rain, snow, or high windvelocities, nor when welders are exposed to inclementconditions.

3.1.4 Size and lengths of welds shall be no less thanthose specified by design requirements and detaileddrawings except as allowed by 6.26.1.7. The location ofwelds shall not be changed without approval.

3.1.5 Welds shall be prohibited on the work except asfollows:

(1) Base-metal repair performed in conformance withAASHTO M160 [M160M] (ASTM A 6 [A 6M]), Specifi-cation for General Requirements for Rolled Steel Plates,Shapes, Sheet Piling, and Bars for Structural Use, Article9, by the mill or fabricator

(2) All welds detailed on approved shop drawings

(3) Repair welds authorized by this code

(4) Other welds approved by the Engineer

3.2 Preparation of Base Metal3.2.1 Surfaces and edges to be welded shall be smooth,uniform, and free from fins, tears, cracks, and other dis-continuities which would adversely affect the quality or

strength of the weld. Surfaces to be welded and surfacesadjacent to a weld shall also be free from loose or thickscale, slag, rust, moisture, grease, and other foreignmaterial that would prevent proper welding or produceobjectionable fumes. Mill scale that can withstand vigor-ous wire brushing, a thin rust-inhibitive coating, or antis-patter compound may remain except that all mill scaleshall be removed from the surfaces on which web-to-flange welds are to be made. This provision shall applyto all girders, stringers, beams, columns, towers, rigidframes, arches, truss chord members, and truss webmembers, but shall not apply to secondary (bracing)members. Mill scale shall be prohibited from remainingin the joint boundary of groove welds subject to calcu-lated tensile stress.

3.2.2 In all thermal cutting, the cutting flame shall be soadjusted and manipulated as to avoid cutting beyond(inside) the prescribed lines. The roughness of thermalcut surfaces shall be no greater than that defined by theAmerican National Standards Institute, ANSI B46.1,Surface Texture. For material up to 100 mm [4 in] thick,the maximum surface roughness value shall be 25 µm[1000 µin]. Steel and weld metal may be thermally cut,provided a smooth and regular surface free from cracksand notches is secured, and provided that an accurateprofile is secured by the use of a mechanical guide. Free-hand thermal cutting shall be done only where approvedby the Engineer.

NOTE: The AWS C4.1-G, Oxygen Cutting SurfaceRoughness Gauge, may be used as a guide for evaluatingsurface roughness of these edges. For materials up toand including 100 mm [4 in] thick, use Sample No. 3,and for materials over 100 mm [4 in] up to 200 mm[8 in] thick, use Sample No. 2.

For material over 100 mm [4 in] through 200 mm [8 in]thick, the maximum surface roughness value shall be50 µm [2000 µin]. The following exception shall beallowed: the ends of members not subject to calculatedstress at the ends shall meet the surface roughness value

3. Workmanship

CLAUSE 3. WORKMANSHIP AASHTO/AWS D1.5M/D1.5:2008

52

of 50 µm [2000 µin]. Roughness exceeding these valuesand occasional notches or gouges no more than 5 mm[3/16 in] deep on otherwise satisfactory surfaces shall beremoved by machining or grinding. Cut surfaces andedges shall be left free of slag. Occasional notches orgouges in material edges, which are not subsequently tobe welded, shall be removed by machining or grinding ifthe actual net cross-sectional area which would remainafter removal of the discontinuity is 98% or greater of thearea of the material based on nominal dimensions. Suchremoval shall be faired to the material edge with a slopenot steeper than one in ten and with machine or grindingmarks parallel to the material surfaces.

3.2.2.1 For steels other than M270M [M270] Grades690/690W [100/100W] (A 709M [A 709] Grades 690/690W [100/100W]) steels, occasional notches or gougesin thermal-cut surfaces, resulting from improper opera-tion of the cutting process, may, with the approval of theEngineer, be repaired by welding. Material discontinui-ties exposed by thermal cutting, such as significant non-metallic inclusions, shall not be repaired by weldingunless RT or UT have defined the limits of the defectsand the Engineer has approved the methods of defectremoval and repair.

Approved repairs shall be made by (1) suitably preparingthe discontinuity for welding, (2) welding using anapproved low-hydrogen WPS, (3) observing all applica-ble requirements of this code, and (4) grinding the com-pleted weld smooth and flush with the adjacent surface toproduce a workmanlike finish (see 3.6.3). Repair weldsin members subject to tension or reversal of stress shallbe inspected as described in 3.2.2.3.

3.2.2.2 For M270M [M270] Grades 690/690W [100/100W] (A 709M [A 709] Grades 690/690W [100/ 100W])steels, defects in thermal cut surfaces shall not berepaired by welding except with the approval of theEngineer for occasional gouges and notches as follows:

(1) Notches or gouges of not more than 5 mm[3/16 in] deep in plate edges which will form the facesof a groove welded joint and which will be subsequentlycompletely fused with the weld may be repaired by weld-ing. Nonmetallic stringers or pipe opening to those edgesshall be removed to a depth of 6 mm [1/4 in] below thesurface by grinding or chipping, and the gouge shall berepaired by welding. Laminations opening to these edgesshall be repaired in conformance with 3.2.3.

(2) Notches or gouges not more than 5 mm [3/16 in]deep in material edges which will form a fillet weldedcorner joint may be repaired by welding only on the partof the edge which will become the faying surface for thejoint and the fusion zone of the fillet weld. The part of

the defect outside the toe of the completed fillet weldshall be removed in conformance with 3.2.2.

(3) Repair shall be made by suitably preparing thedefective area, then welding in conformance with fol-lowing an approved WPS and the applicable require-ments of Clause 4. The completed weld shall be groundsmooth and flush (see 3.6.3) with the adjacent surface toproduce a workmanlike finish.

3.2.2.3 Welded repairs to the surfaces and edges oftension and reversal-of-stress members shall be subjectto UT and MT. Weld quality shall conform to therequirements of 6.26.

3.2.3 Visual Inspection and Repair of Base Metal CutEdges

NOTE: The requirements of 3.2.3 may not be adequate incases of tensile load applied through the thickness of thematerial.

3.2.3.1 The following provisions shall apply to allow-able repairs to discontinuities discovered by either (1)visual inspection of base-metal cut edges before fabri-cation or welding, or (2) during routine examinationof welded joints by RT or UT, in all steels covered bythese specifications, in thicknesses up to and including100 mm [4 in] maximum.

These discontinuities principally result from gas pocketsor blow holes and shrinkage cavities which are mani-fested as “laminations” or “pipe” characterized by a dis-tinct separation of metal parallel to the plane of the basemetal. To a lesser extent, these discontinuities resultfrom entrapped slag, refractory, or deoxidation productsmanifested as deposits of foreign material in the steel,parallel to the plane of the base metal. Multiple disconti-nuities located in the same plane shall be considered con-tinuous when they are separated by a distance less than5% of the base metal thickness, or the length of thesmaller of two adjacent discontinuities.

3.2.3.2 The limits of acceptability and the repair ofvisually observed edge discontinuities shall be in con-formance with Table 3.1, in which the length of disconti-nuity is the visible long dimension on the cut edge of thebase metal and the depth is the distance that the disconti-nuity extends into the base metal from the cut edge.Base-metal edges may be at any angle with respect to thedirection of rolling, but the direction of discontinuitiesshall be considered with respect to the direction of thebase-metal edges. The limits of all internal discontinuitiesrequired to be explored which are not explored to theirfull depth by other means, shall be determined by UT.

3.2.3.3 In making any repairs, the amount of metalremoved shall be the minimum necessary to remove the

AASHTO/AWS D1.5M/D1.5:2008 CLAUSE 3. WORKMANSHIP

53

discontinuity or determine that the allowable limit shallnot be exceeded. Gouging of the discontinuity may bedone from either the base-metal surface or edge. Allrepairs of discontinuities by welding shall conform to theapplicable provisions of this code and an approved WPS.

3.2.3.4 The corrective procedures described in Table3.1 shall not apply to discontinuities in rolled base-metalsurfaces. Such discontinuities may be corrected by thefabricator in conformance with the provisions ofAASHTO M160 [M160M] (ASTM A 6 [A 6M]).

3.2.3.5 Edges of base metal shall be inspected, andrequired repairs shall be completed as early as feasible inthe fabrication sequence so as to allow maximum oppor-tunity for the fabricator to incorporate repaired plates inthe least critical areas.

3.2.3.6 Discontinuities in a base-metal edge such asType Y in Figure 3.1 shall be removed by machining orgrinding if the actual net cross-sectional area whichwould remain after removal of the discontinuity is 98%or greater of the area of the base metal based on nominaldimensions. Such removals shall be faired to the basemetal edge with a slope not exceeding one in ten.Machining or grinding marks perpendicular to theapplied stress shall not exceed a surface roughness of3 µm [125 µin]. Welding repairs shall be prohibited forType Y discontinuities in M270M [M270] Grades 690/690W [100/100W] (A 709M [A 709] Grades 690/690W[100/100W]) steels. In steels other than M270M [M270]Grades 690/690W [100/100W] (A 709M [A 709] Grades690/690W [100/100W]) steels, a Type Y discontinuitymay be repaired by welding with the approval of theEngineer.

3.2.3.7 For discontinuities over 25 mm [1 in] in lengthwith depth found to be greater than 25 mm [1 in], discov-ered before welding by visual inspection of cut edges ofbase metal, or found in welded joints during examinationby RT or UT, the following procedures should beobserved:

(1) Where discontinuities such as W, X, or Y in Fig-ure 3.1 are observed prior to completing the joint, thesize and shape of the discontinuity shall be determinedby UT. The area of the discontinuity shall be determinedas the area of total loss of back reflection, when tested inconformance with the procedure of ASTM A 435/A 435M,Specification for Straight Beam Ultrasonic Examination ofSteel Plates.

(2) For acceptance of Type W, X, and Y discontinui-ties, the area of the discontinuity (or the aggregate areaof multiple discontinuities) shall not exceed 4% of theplate area (plate length times plate width) with the fol-lowing exception. If the length of the discontinuity, or

the aggregate width of discontinuities on any transversesection, as measured perpendicular to the base-metallength, exceeds 20% of the base-metal width, the 4%restriction of base-metal area shall be reduced by thepercentage amount of the width exceeding 20%. (Forexample, if a discontinuity is 30% of the base-metalwidth, the area of discontinuity cannot exceed 3.6% ofthe base-metal area.)

The discontinuity on the cut edge of the base metal shallbe gouged out to a depth of 25 mm [1 in] beyond itsintersection with the surface by chipping, air carbon arcgouging, or grinding, and shall be blocked offby SMAW in layers not exceeding 3 mm [1/8 in] inthickness.

(3) If a discontinuity Z, not exceeding the allowablearea in 3.2.3.7(2), is discovered after the joint has beencompleted and is determined to be 25 mm [1 in] or moreaway from the face of the weld, as measured on the base-metal surface, no repair of the discontinuity shall berequired. If the discontinuity Z is less than 25 mm [1 in]away from the face of the weld, it shall be gouged out toa distance of 25 mm [1 in] from the fusion zone of theweld by chipping, air carbon arc gouging, or grinding. Itshall then be blocked off by welding with low-hydrogenSMAW electrodes for at least four layers not exceeding3 mm [1/8 in] in thickness per layer. SAW or otherwelding processes may be used for the remaining layers.

(4) If the area of the discontinuity W, X, Y, or Zexceeds the allowable in 3.2.3.7(2), the base metal orsubcomponent shall be rejected and replaced, or repairedat the discretion of the Engineer.

(5) The aggregate length of weld repair shall notexceed 20% of the length of the base-metal edge withoutapproval of the Engineer.

(6) For discontinuities of Types W and X, all repairwelds in M270M [M270] Grades 690/690W [100/100W](A 709M [A 709] Grades 690/690W [100/100W]) steelsshall be made with low-hydrogen electrodes not exceed-ing 4.0 mm [5/32 in] in diameter. All repair welds inM270M [M270] Grades 690/690W [100/100W](A 709M [A 709] Grades 690/690W [100/100W]) steelsshall be inspected not less than 48 hours after they are com-pleted, and the groove weld shall not be made until afterthe repair weld has been approved by the Engineer.

(7) All repair welding shall conform to the require-ments of an approved WPS.

3.2.4 Reentrant corners of base-metal cut edges shall beformed to provide a smooth transition with a radius ofnot less than 25 mm [1 in] that meets the adjacent edgeswithout offset or cutting past the point of tangency. Thereentrant corners may be formed by thermal cutting,


54

followed by grinding to meet the surface requirements of3.2.2.

3.2.5 Radii of beam copes and weld access holes shallprovide a smooth transition, free of notches or cuttingpast the points of tangency between adjacent surfaces.

3.2.6 Joint and edge preparation may be done by machin-ing, thermal cutting, air carbon arc cutting and gouging,or chipping and grinding. Removal of unacceptable weldor base metal and backgouging shall be done by machin-ing, air carbon arc gouging, or chipping and grinding.

Oxygen cutting shall not be used for partial removal ofwelds when slag or other materials may deflect the oxy-gen stream and damage the remaining metal. Where anycarbon arc gouging or cutting is involved, proper arcgouging procedures shall be used to avoid the retentionof carbon deposits and material or dross in the areaswhich are to be welded. Air carbon arc gouged surfacesshall be ground to bright metal.

3.2.7 Edges of built-up beam and girder webs shall be cutto the prescribed camber with suitable allowance forshrinkage due to cutting and welding. However, mem-bers with camber exceeding the tolerances of 3.5.1.3may be corrected by heating as described in 3.4.8.Excess camber may be corrected by heating without theEngineer’s approval.

3.2.8 Corrections of errors in camber of quenched andtempered steel shall be given prior approval by theEngineer.

3.2.9 All corners of oxygen cut edges of main stress-carrying members, except bearing stiffeners and girderwebs, shall have a 2 mm [1/16 in] radius or equivalentflat surface at a suitable angle.

3.2.10 Edges of material thicker than specified in the fol-lowing list shall be trimmed if and as required to producea satisfactory welding edge wherever a weld along theedge is to carry calculated stress:

Sheared edges of material 12 mmthicker than [1/2 in]

Rolled edges of plates (other than 10 mmuniversal mill plates) thicker than [3/8 in]

Toes of angles or rolled shapes (other 16 mmthan wide flange sections) thicker than [5/8 in]

Universal mill plates or edges of flanges 25 mmof wide flange sections thicker than [1 in]

The form of edge preparation for butt joints shall con-form to the requirements of 2.12 except as modified by2.7.

3.3 Assembly3.3.1 The parts to be joined by fillet welds shall bebrought into as close contact as practicable. The rootopening shall not exceed 5 mm [3/16 in] except in casesinvolving either shapes or plates 75 mm [3 in] or greaterin thickness if, after straightening and in assembly, theroot opening cannot be closed sufficiently to meet thistolerance. In such cases, a maximum root opening of8 mm [5/16 in] may be used, with a backing weld orsuitable backing. If the root opening is greater than 2 mm[1/16 in], the leg of the fillet weld shall be increased bythe amount of the root opening or the Contractor shalldemonstrate that the required weld size has beenobtained.

3.3.1.1 The separation between faying surfaces ofplug and slot welds, and of butt joints landing on a back-ing, shall not exceed 2 mm [1/16 in].

3.3.1.2 The use of filler plates shall be prohibitedexcept as specified on the drawings or as speciallyapproved by the Engineer and made in conformance with2.5.

3.3.2 The root opening between parts to be joined by PJPgroove welds parallel to the member length (bearingjoints excepted) shall be zero, or as small as practicable.

3.3.2.1 The root opening between parts shall notexceed 5 mm [3/16 in] except in cases involving rolledshapes or plates 75 mm [3 in] or greater in thickness if,after straightening and in assembly, the root openingcannot be closed sufficiently to meet this tolerance. Insuch cases, a maximum root opening of 8 mm [5/16 in]may be used with a backing weld or suitable backing andthe final weld meets the requirements for weld size.

3.3.2.2 Tolerances for bearing joints shall be in con-formance with the applicable contract specifications.

3.3.3 Parts to be joined by groove welds shall be care-fully aligned. Where the parts are effectively restrainedagainst bending due to eccentricity in alignment, the off-set from theoretical alignment shall not exceed 10% ofthe thickness of the thinner part joined, but in no caseshall be more than 3 mm [1/8 in]. In correcting misalign-ment in such cases, the parts shall not be drawn in to agreater slope than 12 mm [1/2 in] in 300 mm [12 in].Measurement of offset shall be based upon the centerlineof parts unless otherwise shown on the drawings.

3.3.4 With the exclusion of ESW and EGW, and with theexception of 3.3.4.1 for root openings in excess of thoseallowed below and illustrated in Figure 3.2, the dimen-sions of the cross section of the groove welded jointswhich vary from those shown on the detail drawings by


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more than the tolerances shown in Figure 3.2 shallrequire approval by the Engineer for correction.

3.3.4.1 Root openings wider than those allowed in3.3.4, but not greater than twice the thickness of the thin-ner part or 20 mm [3/4 in], whichever is less, may be cor-rected by welding to acceptable dimensions prior tojoining the parts by welding.

3.3.4.2 Root openings larger than those allowed in3.3.4.1 may be corrected by welding only with theapproval of the Engineer.

3.3.5 Groove preparations produced by gouging shall besubstantially in conformance with groove profile dimen-sions as described in Figures 2.4 and 2.5.

3.3.6 Members to be welded shall be brought into correctalignment and held in position by bolts, clamps, wedges,guy lines, struts, and other suitable devices, or by tackwelds until welding has been completed. The use of jigsand fixtures is recommended where practicable. Suitableallowances shall be made for warpage and shrinkage (see3.4.4, 3.4.5, 3.4.6, and 3.4.7.)

3.3.7 Tack Welds

3.3.7.1 Tack welds shall be subject to the same qualityrequirements as the final welds, with the followingexceptions:

(1) Preheat is not mandatory for single-pass tackwelds which are remelted and incorporated into continu-ous SAW, ESW, or EGW welds.

(2) Discontinuities such as undercut, unfilled craters,and porosity need not be removed before the final SAW,ESW, or EGW that remelts the tack weld (see 3.3.8).

3.3.7.2 Tack welds which are incorporated into thefinal weld shall be made with electrodes meeting therequirements of the final welds and shall be cleaned thor-oughly. Multiple-pass tack welds shall have cascadedends.

Allowable Root Openings

RootNot Gouged,

mm [in]

RootGouged,mm [in]

(1) Root face of joint ±2 [±1/16] Not limited

(2) Root opening of joints without steel backing

±2 [±1/16] +2 [+1/16]–3 [–1/8]

Root opening of joints with steel backing

+6 [+1/4]]–2 [–1/16]

Notapplicable

(3) Groove angle of joint +10°–5°

+10°–5°

3.3.7.3 Tack welds not incorporated into the finalweld shall be removed in such a manner that the basemetal is not nicked or undercut. Repair of base metalaccidentally removed shall be approved by the Engineerprior to making the repair. If the repair involves welding,it shall be in conformance with 3.7.1.

3.3.7.4 The removal of tack welds may expose unac-ceptably hard or cracked HAZs. Such areas on memberssubject to tension or reversal-of-stress shall be tested byMT (preferably by the yoke method) to assure that nocracks are present. Hardness tests are recommended todetermine that HAZ remaining in the structure are notunacceptably hard. Hardness values shall not exceedRockwell C30 in the HAZ or the hardness value mea-sured in the unaffected base metal, whichever is higher.Since HAZ hardening generally extends less than 3 mm[1/8 in] into the base metal, unacceptable hardening canbe removed by shallow grinding.

3.3.7.5 Tack welding of steel backing should be donewithin the joint so that all tack welds will be remeltedand incorporated within the final weld.

3.3.7.6 Tack welds used to attach steel backing andplaced external to the weld joint shall be made continu-ous by fillet welding for the full length of the backing orshall be removed.

3.3.8 Temporary Welds. Temporary welds shall be sub-ject to the same WPS requirements as final welds. Theyshall be removed unless otherwise allowed by the Engi-neer. When they are removed, the surface shall be madeflush with the original surface. There shall be no tempo-rary welds in tension zones of members of quenched andtempered steels. Temporary welds at other locations shallbe shown on shop drawings. Removal of temporary weldsshall conform to the requirements of 3.3.7.3 and 3.3.7.4.

3.3.9 Joint Root Openings. Joint root openings mayvary as described in 2.9 and 2.10. However, for auto-matic or machine welding using FCAW, GMAW, orSAW, the maximum root opening variation (minimum tomaximum opening as fit-up) may not exceed 3 mm[1/8 in]. Variations greater than 3 mm [1/8 in] shall belocally corrected prior to automatic or machine welding.

3.3.10 Assembly Sequence. J- and U-grooves may beprepared before or after assembly. Second-side groovesmay be prepared by air carbon arc gouging and grindingafter welding the first side. Before welding, the J- or U-groove shall conform to the provisions of this clause.

3.3.11 Joint Detail Dimensional Tolerances. Dimen-sions of groove welds specified on design or detaileddrawings may vary from the dimensions shown in Figure2.4 or Figure 2.5 within the limits described in 3.3.4. J-and U-grooves may be prepared before or after assembly.


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3.4 Control of Distortion and Shrinkage

3.4.1 In assembling and joining parts of a structure or ofbuilt-up members and in welding reinforcing parts tomembers, the procedure and sequence shall minimizedistortion and shrinkage.

3.4.2 Insofar as practicable, all welds shall be made in asequence that will balance the applied heat of weldingwhile the welding progresses.

3.4.3 The Contractor shall prepare a welding sequencefor a member or structure which, in conjunction with theWPSs and overall fabrication methods, will producemembers or structures meeting the quality requirementsspecified. The welding sequence and distortion controlprogram shall be submitted to the Engineer, for informa-tion and comment, before the start of welding on a mem-ber or structure in which shrinkage or distortion is likelyto affect the adequacy of the member or structure. Thedistortion control program shall include standardmechanical or heat straightening procedures to be uti-lized when common distortion control practice must besupplemented to achieve specified tolerances.

3.4.4 The direction of the general progression in weldingon a member shall be from points where the parts arerelatively fixed in position with respect to each othertoward points where they have a greater relative freedomof movement.

3.4.5 Joints expected to have significant shrinkageshould usually be welded before joints expected to havelesser shrinkage. They should also be welded with aslittle restraint as possible.

3.4.6 All shop splices in each component part of a cover-plated beam or built-up member shall be made before thecomponent part is welded to other component parts ofthe member. Long members or member sections may bemade by shop or field splicing subsections, each made inconformance with this subclause (see 2.17.6).

3.4.7 In making welds under conditions of severe exter-nal shrinkage restraint, the welding shall be carried con-tinuously to completion or to a point that will ensurefreedom from cracking before the joint is allowed to coolbelow the minimum specified preheat and interpasstemperature.

3.4.8 Members distorted by welding shall be straightenedby mechanical means and/or by carefully supervisedapplication of a limited amount of localized heat. Thetemperature of the heated areas as measured by approvedmethods shall not exceed 600°C [1100°F] for Grade HPS485W [HPS 70W] and 690/690W [100/100W] steels or650°C [1200°F] for other steels. The part to be heated for

straightening shall be substantially free of stress fromexternal forces, except stresses resulting from themechanical straightening methods used in conjunctionwith the application of the heat.

3.5 Dimensional Tolerances3.5.1 The dimensions of welded structural members shallconform to the tolerances of (1) the general specifica-tions governing the work, and (2) the special dimen-sional tolerances in 3.5.1.1 to 3.5.1.12.

3.5.1.1 Allowable variations in straightness of weldedcolumns and primary truss members, regardless of crosssection, shall not exceed

Lengths of less than 10 m [30 ft]

1 mm/m ([1/8 in/10 ft] of total length, m [ft]

Lengths of 10 to 15 m [30 to 45 ft], 10 mm [3/8 in]

Lengths over 15 m [45 ft]

10 mm + 1 mm/m × [length (m) – 15 m]

3/8 in + 1/8 in/10 ft × [length (ft) – 45 ft]

3.5.1.2 Allowable variations in straightness of weldedbeams or girders, regardless of cross section, where thereis no specified camber or sweep, shall not exceed

1 mm/m [1/8 in/10 ft] of total length, m [ft]

3.5.1.3 For welded beams or girders, with the topflange not embedded in concrete or with the top flangeembedded in concrete with a designed haunch, regard-less of cross section, the allowable variation fromrequired camber at shop assembly (for drilling holes forfield splices or preparing field welded splices) shall be

at midspan, –0, +40 mm [1-1/2 in] for spans ≥30 m[100 ft]

–0, +20 mm [3/4 in] for spans <30 m [100 ft]

at supports, 0 for end supports

±3 mm [1/8 in] for interior supports

at intermediate points, –0, +

where

a = distance in meters [ft] from inspection point tonearest support

S = span length in meters [ft]

b = 40 mm [1-1/2 in] for spans ≥30 m [100 ft]

b = 20 mm [3/4 in] for spans <30 m [100 ft]

4 (a) b (1 – a/S)S

-------------------------------------


57

See Table 3.2 for tabulated values.

For members whose top flange is embedded in concretewithout a designed concrete haunch, the allowable varia-tion from required camber at shop assembly (for drillingholes for field splices or preparing field welded splices)shall be

at midspan, ±20 mm [3/4 in] for spans ≥30 m [100 ft]

±10 mm [3/8 in] for spans <30 m [100 ft]

at supports, 0 for end supports

±3 mm [1/8 in] for interior supports

at intermediate points, ±

where

a and S are as defined above

b = 20 mm [3/4 in] for spans ≥30 m [100 ft]

b = 10 mm [3/8 in] for spans <30 m [100 ft]

See Table 3.3 for tabulated values.

Regardless of how the camber is shown on the detaildrawings, the sign convention for the allowable variationis plus (+) above, and minus (–) below, the detailedcamber shape.

These provisions shall also apply to an individual mem-ber when no field splices or shop assembly is required.

Camber measurements shall be made in the no-loadcondition.

3.5.1.4 Allowable variation in specified sweep forhorizontally curved welded beams or girders shall be1 mm/m [1/8 in/10 ft] of total length, m [ft], providedthe member has sufficient lateral flexibility to allow theattachment of diaphragms, cross-frames, lateral bracing,etc., without damaging the structural member or itsattachments.

3.5.1.5 Allowable lateral variation between the actualand theoretical web centerline at the flange surface shallnot exceed 6 mm [1/4 in].

3.5.1.6 For allowable variations from flatness of webfor girders, see (1) through (4) below:

(1) Variations from flatness of girder webs shall bedetermined by measuring offsets from a straight edgewhose length is no less than the least dimension of anypanel. The straight edge shall be placed in any positionof maximum variation on the web with the ends of thestraight edge adjacent to opposite panel boundaries.

4 (a) b (1 – a/S)S

-------------------------------------

(2) Variation from flatness of webs having a depth,D, and a thickness, t, in panels bounded by stiffeners orflanges, or both, whose least panel dimension is d shallnot exceed the following (all dimensions in mm [in]):

Intermediate stiffeners on both sides of web:

Interior girders—where D/t < 150—maximum variation = d/115where D/t ≥ 150—maximum variation = d/92

Fascia girders—where D/t < 150—maximum variation = d/130where D/t ≥ 150—maximum variation = d/105

Intermediate stiffeners on one side only of web:

Interior girders—where D/t < 100— maximum variation = d/100where D/t ≥ 100— maximum variation = d/67

Fascia girders —where D/t < 100—maximum variation = d/120where D/t ≥ 100—maximum variation = d/80

No intermediate stiffeners—maximum variation = D/150

See Annex C for tabulation.

(3) Web distortion of twice the allowable tolerancesof 3.5.1.6(2) shall be satisfactory when occurring at theend of a girder which has been drilled, or subpunchedand reamed either during assembly or to a template fora field bolted splice, provided, when the splice platesare bolted, the web assumes the proper dimensionaltolerances.

(4) If architectural considerations require tolerancesmore restrictive than described above, specific referenceshall be included in the bid documents.

3.5.1.7 Combined warpage and tilt of flange at anycross section of welded I-shape beams or girders shall bedetermined by measuring the offset at the toe of theflange from a line normal to the plane of the web throughthe intersection of the centerline of the web with the out-side surface of the flange plate. This offset shall notexceed 1/100 of the total width of the flange or 6 mm[1/4 in], whichever is greater, at any point along themember, except that at any bearing this offset should notexceed that described in 3.5.1.9 and that abutting parts tobe joined by groove welds in butt joints shall conform to3.3.3.

3.5.1.8 The maximum allowable variation from speci-fied depth for welded beams and girders, measured at theweb centerline, shall not exceed

For depths up to 1 m [36 in]inclusive............................................... ±3 mm [1/8 in]


58

For depths over 1 m to 2 m[36 in to 72 in] inclusive...................... ±5 mm [3/16 in]

For depths over 2 m [72 in] ................. +8 mm [5/16 in],–5 mm [3/16 in]

3.5.1.9 The bearing ends of bearing stiffeners shall beflush and square with the web and shall have at least 75%of this area in contact with the flanges.

When bearing against a steel base or seat, all steel com-ponents shall fit within 1 mm [1/32 in] for 75% of theprojected area of the web and stiffeners. Girders withoutstiffeners shall bear on the projected area of the web onthe outer flange surface within 1 mm [1/32 in] and theincluded angle between web and flange shall not exceed90° in the bearing length.

3.5.1.10 Where tight fit of intermediate stiffeners isspecified, it shall be defined as allowing a gap of up to2 mm [1/16 in] between stiffener and flange.

3.5.1.11 The out-of-straightness variation of inter-mediate stiffeners shall not exceed 12 mm [1/2 in] withdue regard to any members which frame into them.

3.5.1.12 The out-of-straightness variation of bearingstiffeners shall not exceed 6 mm [1/4 in] up to 2 m [6 ft]or 12 mm [1/2 in] over 2 m [6 ft]. The actual centerlineof the stiffener shall lie within the thickness of the stiff-ener as measured from the theoretical centerline location.

3.5.1.13 Other dimensional tolerances not covered by3.5 shall be individually determined and mutually agreedupon by the Contractor and the Engineer with properregard for erection requirements.

3.5.1.14 Mechanically connected joints and splices ofmain stress carrying members with surfaces intended tobe parallel planes shall be nearly parallel after connec-tion, and the surfaces to be in contact shall have an offsetno greater than 2 mm [1/16 in] after all filler plates havebeen added, if any.

3.5.1.15 The corresponding surfaces of secondarymember parts, at mechanically fastened connections,shall show no offset greater than 3 mm [1/8 in].

3.5.2 Ends of members fabricated by welding which areto be field connected by welding shall be shop assembledor assembled to a template to ensure conformance to3.3.1, 3.3.2, 3.3.3, and 3.3.4.

3.6 Weld Profiles3.6.1 The faces of fillet welds may be slightly convex,flat, or slightly concave as shown in Figure 3.3(A) and

(B), with none of the unacceptable profiles shown in Fig-ure 3.3(C).

3.6.1.1 Except at outside welds in corner joints, theconvexity C of a weld or individual surface bead shallnot exceed 0.07 times the actual face width of the weldor individual bead, respectively, plus 1.5 mm [0.06 in][see Figure 3.3(B)].

3.6.1.2 Except for undercut, as allowed by the code,these profile requirements shall not apply to the ends ofintermittent fillet welds outside their effective lengths.The profile exclusion at the end of intermittent filletwelds outside their effective lengths does not modify theweld quality provisions of 6.26.

3.6.2 Groove welds shall preferably be made with slightor minimum face reinforcement except as may be other-wise provided. In the case of butt and corner joints, theface reinforcement shall not exceed 3 mm [1/8 in] inheight and shall have gradual transition to the plane ofthe base metal surface [see Figure 3.3(D)]. They shall befree of the discontinuities shown for butt joints in Figure3.3(E).

3.6.3 Surfaces of butt joints required to be flush shall befinished so as not to reduce the thickness of the thinnerbase metal or weld metal by more than 1 mm [1/32 in] or5% of the thickness, whichever is smaller, nor leave rein-forcement that exceeds 1 mm [1/32 in]. Unless otherwiseapproved by the Engineer, all reinforcement shall beremoved where the weld forms a part of a faying surface.Any reinforcement shall blend smoothly into the platesurfaces with transition areas free from weld edge under-cut. Chipping may be used, provided it is followed bygrinding.

3.6.4 Where surface finishing is required, surface rough-ness values shall not exceed 6 µm [250 µin]. Surfacesfinished to values over 3 µm [125 µin] through 6 µm[250 µin] shall be finished parallel to the direction ofprimary stress. Surfaces finished to values of 3 µm[125 µin] or less may be finished in any direction, sub-ject to the following additional requirements: butt jointsbetween parts subject to tensile stress, whether joiningparts of equal or unequal width or thicknesses shall befinished flush, or to a smooth transition, to a roughnessnot exceeding 3 µm [125 µin].

3.6.5 Welds shall be free from overlap.

3.7 Repairs3.7.1 The removal of weld metal or portions of the basemetal may be done by machining, air carbon arc cuttingand gouging, thermal cutting, chipping, or grinding. It


59

shall be done in such a manner that the remaining weldmetal or base metal is not nicked or undercut (see 3.2.6for restrictions on the use of air carbon arc gouging andthermal cutting). Unacceptable portions of the weld shallbe removed without substantial removal of the basemetal. Any additional weld metal shall be depositedusing a qualified WPS. The surface shall be thoroughlycleaned before welding.

3.7.2 The Contractor has the option of either repairing anunacceptable weld, or removing and replacing the entireweld or the entire assembly, except as modified by 3.7.4.The repaired or replaced weld shall be reinspected by themethod originally used, and the same technique andquality acceptance criteria shall be applied. If the Con-tractor elects to repair the weld, it shall be corrected asfollows:

3.7.2.1 Overlap or Excessive Convexity. Excessweld metal shall be removed.

3.7.2.2 Excessive Concavity of Weld or Crater,Undersize Welds, Undercutting. Surfaces shall be pre-pared (see 3.11) and additional weld metal deposited.

3.7.2.3 Excessive Weld Porosity, Excessive SlagInclusions, Incomplete Fusion. Unacceptable portionsshall be removed (see 3.7.1) and rewelded.

3.7.2.4 Cracks in Weld or Base Metal. The extent ofthe crack shall be ascertained by use of MT, PT, or otherequally positive means; the metal shall be removed forthe full length of the crack plus 50 mm [2 in] beyondeach end of the crack, and rewelded.

3.7.3 As approved by the Engineer, members damagedor distorted beyond that considered in the distortion con-trol plan may be straightened by mechanical means or bycarefully supervised application of a limited amount oflocalized heat. The temperature shall be as described in3.4.8.

3.7.4 Prior approval of the Engineer shall be obtained forrepairs to base metal (other than those required by 3.2),repair of major or delayed cracks, repairs to ESW andEGW welds with internal defects, or for a revised designto compensate for deficiencies.

3.7.5 The Engineer shall be notified before improperlyfitted and welded members are cut apart.

3.7.6 If, after an unacceptable weld has been made, workis performed which has rendered that weld inaccessibleor has created new conditions that make correction of theunacceptable weld dangerous or ineffectual, then theoriginal conditions shall be restored by removing weldsor members, or both, before the corrections are made. Ifthis is not done, the deficiency shall be compensated for

by additional work performed according to an approvedrevised design.

3.7.7 Welded Restoration of Material with MislocatedHoles. Except where restoration by welding is necessaryfor structural or other reasons, punched or drilled mis-located holes may be left open or may be filled with abolt. When base metal with mislocated holes is restoredby welding, the following requirements apply:

3.7.7.1 Base metal not subjected to dynamic tensilestress may be restored by welding, provided the Contrac-tor prepares and follows a repair WPS. The repair weldsoundness shall be verified by UT or RT as approved bythe Engineer.

3.7.7.2 Base metal subject to dynamic tensile stressmay be restored by welding providing the followingapply:

(1) The Engineer approves both repair by weldingand the repair WPS.

(2) The repair WPS is followed in the work and thesoundness of the restored base metal is verified by UT orRT, as specified in the contract documents for examinationof tension groove welds or as approved by the Engineer.

3.7.7.3 In addition to the requirements of 3.7.7.1 and3.7.7.2, when holes in quenched and tempered steels arerestored by welding the following shall apply:

(1) Appropriate filler metal, heat input, and postweldheat treatment (when PWHT is required) shall be used.

(2) Sample welds shall be made using the repairWPS.

(3) RT of the sample welds shall verify that weldsoundness conforms to the requirements of 6.26.2.1.

(4) One reduced section tension test (weld metal),two side-bend tests (weld metal); and three CVN tests ofthe HAZ (coarse grained area) removed from samplewelds shall be used to demonstrate that the mechanicalproperties of the repaired area conform to the specifiedrequirements of the base metal.

3.7.7.4 Weld surfaces shall be finished as specified in3.6.3.

3.8 Peening3.8.1 When approved by the Engineer, peening may beused to prevent cracking and lamellar tears by mechani-cally reducing residual stresses created by welding. Toprevent sharp impressions, peening shall be performedby mechanically striking convex surfaces of intermediateweld beads or layers with a round tool with a 6 mm


60

[1/4 in] radius (unless otherwise approved). Root andfinal passes shall not be peened. When approved by theEngineer, final passes that contain excess weld metalmay be peened, provided all of the excess weld metaland all peening marks are removed by grinding.

Peening shall be done when the weld is at a temperatureof 65°C–260°C [150°F–500°F]. Care shall be taken toavoid striking fusion boundaries or the base metal. Peen-ing energy shall be sufficient to mechanically elongatethe surface of the weld without creating overlapping orcracking. Pneumatic tools shall be operated in a mannerthat prevents contamination of the weld by moisture, oil,or other materials.

3.8.2 Manual slag hammers, chisels, and lightweight vibrat-ing tools for the removal of slag and spatter may be usedand shall not be considered peening.

3.9 CaulkingCaulking of welds shall be prohibited.

3.10 Arc StrikesCare shall be taken to avoid arc strikes outside the area ofpermanent welds on any base metal. Cracks or blemishescaused by arc strikes shall be ground to remove all of thedefect. On tension and reversal of stress members, MT(preferably the yoke method) shall be used to determinethat no cracks are present in the structure (see 6.7.6.2).Hardness tests shall be employed as stated in 3.3.7.4.

3.11 Weld Cleaning3.11.1 In-Process Cleaning. Before welding over previ-ously deposited metal, all slag shall be removed and theweld and adjacent base metal shall be brushed clean.This requirement shall apply not only to successive lay-ers but also to successive beads and to the crater areawhen welding is resumed after any interruption. It shallnot, however, restrict the welding of plug and slot weldsin conformance with 4.21 and 4.22.

3.11.2 Cleaning of Completed Welds. Slag shall beremoved from all completed welds, and the weld andadjacent base metal shall be cleaned by brushing or othersuitable means. Tightly adherent spatter remaining afterthe cleaning operation shall be acceptable unless itsremoval shall be required for the purpose of NDT orpainting. Welded joints shall not be painted until afterwelding has been completed and the weld has beenaccepted.

3.12 Weld Termination3.12.1 Welds shall be terminated at the end of a joint in amanner that will ensure sound welds. Whenever possi-ble, this shall be done by use of weld tabs (extension barsand runoff plates) placed in a manner that will duplicatethe joint detail being welded.

3.12.2 Weld Tabs. Weld tabs used in welding shall con-form to the following requirements:

(1) The weld tab may be of any of the steelsdescribed in 1.2.2 except that Grade 690 [100] or 690W[100W] tabs shall not be used on lower strength steels.

(2) Base metal used as temporary weld extensionsshall be exempt from toughness testing.

3.12.3 Weld tabs (extension bars and run off plates) shallbe removed upon completion and cooling of the weld,and the ends of the welds shall be made smooth and flushwith the edges of the abutting parts.

3.12.4 Ends of welded butt joints required to be flushshall be finished so as not to reduce the width beyond thedetailed width or the actual width furnished, whicheveris greater, by more than 3 mm [1/8 in] or so as not toleave reinforcement at each end that exceeds 3 mm[1/8 in]. Ends of welded butt joints shall be faired toadjacent plate or rolled shape edges at a slope not toexceed 1 in 10 unless otherwise shown on the drawings.

3.13 Weld Backing3.13.1 Backing. Steel backing shall conform to the fol-lowing requirements:

(1) When welding any approved steel described in1.2.2, backing may be of any of the steels described in1.2.2 except that Grade 690 [100] or 690W [100W]backing shall not be used on lower strength steels.

(2) When welding a steel qualified in conformancewith 5.4.3, backing may be HPS 485W [HPS 70W], 345[50], 345W [50W], HPS 345W [HPS 50W], 250 [36], orthe steel qualified.

(3) Backing not exceeding 10 mm × 30 mm [3/8 in ×1-1/4 in], furnished as bar stock or cut from plate, shallbe exempt from CVN testing requirements.

3.13.2 Groove welds made with the use of steel backingshall have the weld metal thoroughly fused with thebacking. Steel backing shall be continuous for the fulllength of each weld made with backing. A continuouslength of backing may be made by welding shorter sec-tions together under the following conditions:


61

(1) All welds shall be CJP groove welds made withthe same controls as similar CJP groove welds in thestructure.

(2) RT or UT shall be used to assure weld soundness.

(3) All welding and testing of the backing shall becomplete before the backing is used to make the struc-tural weld.

3.13.3 Steel backing on welds transverse to the directionof computed stress shall be removed, and the joint shallbe ground smooth. Steel backing parallel to the directionof stress or not subject to computed stress need not beremoved unless specified in the contract documents orordered by the Engineer.

3.13.3.1 For welds in compression in T-joints andcolumns, steel backing need not be removed, unlessrequired by the contract documents or ordered by theEngineer.

3.13.3.2 Where the steel backing of longitudinalwelds is externally attached to the base metal by weld-ing, such welding shall be continuous for the length ofthe backing.

3.13.4 The recommended minimum nominal thickness ofbacking, provided that the backing shall be of sufficientthickness to prevent melting through, is shown in the fol-lowing table:

Process Min. Nom. Thickness, mm [in]

SMAW 5 [3/16]GMAW 6 [1/4]0FCAW-S 6 [1/4]0FCAW-G 10 [3/8]0SAW 10 [3/8]0

3.13.5 Steel backing shall be placed and held in intimatecontact with the base metal. The maximum gap betweensteel backing and the base metal at the weld root shall be2 mm [1/16 in], as shown in Figure 3.2(A).

3.13.6 Groove and fillet welds may be backed by copper,flux, glass tape, iron powder, or similar materials to pro-vide an appropriate back-bead shape or to prevent melt-ing through. Roots of welds may also be sealed by meansof root passes deposited with SMAW low-hydrogenelectrodes or by other approved arc WPSs.

Copper shall not be used as a backing when there is anypossibility that the welding arc may strike the copper.

Welds made against backing other than base metal orapproved low-hydrogen weld metal shall be subject toWPS qualification testing under the provisions of 5.13and approval by the Engineer. In SAW, flux that fillsgaps not exceeding 5 mm [3/16 in] between adjacentparts shall not be considered to be backing and shall notrequire WPS qualification testing.

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Table 3.1Limits on Acceptability and Repair of Cut Edge Discontinuities of Material (see 3.2.3.2)

Description of Discontinuity Plate Repair Required

Any discontinuity 25 mm [1 in] in length or less None, need not be explored.

Any discontinuity over 25 mm [1 in] in length and 3 mm [1/8 in] maximum depth

None, but the depth should be exploreda

Any discontinuity over 25 mm [1 in] in length with depth over3 mm [1/8 in] but not greater than 6 mm [1/4 in]

Remove, need not weld

Any discontinuity over 25 mm [1 in] in length with depth over6 mm [1/4 in] but not greater than 25 mm [1 in]

Completely remove and weldAggregate length of welding shall not exceed 20% of the length of the material edge being repaired

Any discontinuity over 25 mm [1 in] in length with depth greaterthan 25 mm [1 in]

See 3.2.3.7

a A spot check of 10% of the discontinuities on the oxygen-cut surface in question should be explored by grinding to determine depth. If the depth ofany one of the discontinuities explored exceeds 3 mm [1/8 in], then all of the discontinuities remaining on that edge shall be explored by grinding todetermine depth. If none of the discontinuities explored on the 10% spot check have a depth exceeding 3 mm [1/8 in], then the remainder of the dis-continuities on that edge need not be explored.

Table 3.2Camber Tolerance for Typical Girder

(see 3.5.1.3)

Camber Tolerance, mm [in]

a/SSpan 0.1 0.2 0.3 0.4 0.5

≥30 m≥[100 ft]

14[9/16]

25[1]

34[1-1/4]

38[1-7/16]

40[1-1/2]

<30 m<[100 ft]

7[1/4]

13[1/2]

17[5/8]

19[3/4]

20[3/4]

Table 3.3Camber Tolerance for Girders without a Designed Concrete Haunch (see 3.5.1.3)

Camber Tolerance, mm [in]

a/SSpan 0.1 0.2 0.3 0.4 0.5

≥30 m≥[100 ft]

7[1/4]

13[1/2]

17[5/8]

19[3/4]

20[3/4]

<30 m<[100 ft]

4[1/8]

6[1/4]

8[5/16]

10[3/8]

10[3/8]

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Figure 3.1—Discontinuities in Cut Plate (see 3.2.3.6)

Notes:1. a—groove angle.2. R—root opening.3. f—foot face.4. The groove configurations shown are for illustration only.5. All dimensions in mm [in].

Figure 3.2—Workmanship Tolerances in Assembly of Groove Welded Joints (see 3.3.4)

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Figure 3.3—Acceptable and Unacceptable Weld Profiles (see 3.6)


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4.1 Filler Metal Requirements4.1.1 For matching weld metal, the electrode or elec-trode/flux combination shall be selected from Table 4.1or 4.2 for the base metal to be used in the work.

When undermatching filler metal is required or allowedby the contract documents, the electrode or electrode-flux combination shall be of the strength class shown onthe shop drawings, and the filler metal shall be selectedfrom Table 4.1 or 4.2, consistent with design requirements.

4.1.2 The mechanical properties of filler metals used toproduce fillet and groove welds are described in Tables4.1 and 4.2.

4.1.2.1 For weld joints containing M270M [M270](A 709M [A 709]) Grade HPS 485W [HPS 70W] mate-rials, the maximum filler metal diffusible hydrogen con-tent shall not exceed 8 mL/ 100 g of deposited weldmetal as determined by AWS A4.3, Standard Methodsfor Determination of the Diffusible Hydrogen Content ofMartensitic, Bainitic, and Ferritic Steel Weld Metal Pro-duced by Arc Welding, with the preheat requirements ofTable 4.4.

4.1.3 After filler metal has been removed from its origi-nal package, it shall be protected or stored so that itscharacteristics and welding properties are not affected(see 4.5.2).

4.1.4 For exposed, bare, unpainted applications ofM270M [M270] (A 709M [A 709]) Grades 345W [50W]and HPS 345W [HPS 50W] steels requiring weld metalwith atmospheric corrosion resistance and coloring char-acteristics similar to that of the base metal, the electrodeor electrode-flux combination shall be in conformancewith Table 4.3. In multiple-pass welds, the weld metalmay be deposited so that at least two layers on all

exposed surfaces and edges are deposited with one of thefiller metals listed in Table 4.3, provided the underlyinglayers are deposited with one of the filler metalsdescribed in Table 4.1 or Table 4.2.

4.1.5 For single-pass welding, other than ESW or EGW,of exposed, bare, unpainted applications of M270M[M270] (A 709M [A 709]) Grades 345W [50W] andHPS 345W [HPS 50W] steels requiring weld metal withatmospheric corrosion resistance and coloring character-istics similar to that of the base metal, the following vari-ations from Table 4.3 may be made. This shall also applyto unpainted applications of HPS 485W [HPS 70W]when undermatching is allowed.

4.1.5.1 Shielded Metal Arc Welding (SMAW). Sin-gle-pass fillet welds up to 6 mm [1/4 in] maximum and6 mm [1/4 in] groove welds made with a single pass or asingle pass each side may be made using an E70XX low-hydrogen electrode.

4.1.5.2 Submerged Arc Welding (SAW). Single-pass fillet welds up to 8 mm [5/16 in] maximum andgroove welds made with a single pass may be made withan electrode-flux combination conforming to Tables 4.1or 4.2.

4.1.5.3 Gas Metal Arc Welding (GMAW). Single-pass fillet welds up to 8 mm [5/16 in] maximum andgroove welds made with a single pass or a single passeach side may be made using an ER70S-X electrode con-forming to Table 4.2.

4.1.5.4 Flux Cored Arc Welding (FCAW). Single-pass fillet welds up to 8 mm [5/16 in] maximum andgroove welds made with a single pass or single pass eachside, may be made using an E7XT-X electrode conform-ing to Table 4.1 or 4.2.

4.1.6 For ESW or EGW welding of exposed, bare,unpainted applications of M270M [M270] (A 709M[A 709] Grades 345W [50W] and HPS 345W [HPS50W]) steels requiring weld metal with atmospheric cor-rosion resistance and coloring characteristics similar to

4. Technique

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that of the base metal, the electrode or electrode-fluxcombination shall produce weld metal that conforms tothe requirements described in Table 4.3. The chemicalcomposition of the weld metal deposited on a standardfiller metal test pad, where there is minimal dilution ofthe base metal, shall conform to one of the chemicalcompositions provided in the list of electrodes describedin Table 4.3. The chemical composition of depositedESW or EGW weld metal will not exactly match eitherthe electrode or the base metal, since there is consider-able base-metal dilution. The electrode or electrode/ fluxcombination shall be approved by the Engineer.

4.2 Preheat and Interpass Temperature Requirements

The preheat and interpass temperature shall be sufficientto prevent cracking. Experience has shown that the mini-mum temperatures specified in Table 4.4 are adequate toprevent cracking in most cases. However, increased pre-heat temperatures may be necessary in situations involv-ing higher restraint, higher hydrogen, lower welding heatinput, or steel composition at the upper limits of thespecification. Conversely, lower preheat temperaturesmay be adequate to prevent cracking, depending onrestraint, hydrogen level, and actual steel composition orhigher welding heat input.

4.2.1 With the exception of stud welding, ESW, EGW,and tack welding conforming to 3.3.7.1(1), the minimumpreheat and interpass temperatures for redundant mem-bers shall be as specified in Table 4.4.

4.2.1.1 Minimum preheat and interpass temperaturesmay be established on the basis of steel composition,thickness, and restraint using recognized methods of pre-diction such as those provided in Annex G.

NOTE: These methods are based on laboratory crackingtests and may predict preheat temperatures higher thanthe minimum temperatures shown in Table 4.4. Theguide may be of value in identifying situations where therisk of cracking is increased due to composition,restraint, hydrogen level, or welding heat input wherehigher heat input may be warranted. Alternatively, theguide may assist in defining conditions under whichhydrogen cracking is unlikely and where the minimumrequirements of Table 4.4 may be safely relaxed, basedupon WPS qualification testing.

However, should the use of such guidelines result in tem-peratures lower than required by 4.2.1, the minimumtemperature shall be qualified by performing testsacceptable to the Engineer.

4.2.1.2 Optional reduced preheat and interpass tem-peratures for M270M/M270 (A 709M [A 709]) GradeHPS 485W [HPS 70W] may be used in accordance withthe requirements of Annex G.

4.2.2 The maximum preheat and interpass temperatureshall be as specified in the WPS. For M270M [M270](A 709M [A 709]) Grade 690/690W [100/100 W], the max-imum preheat and interpass temperature shall not exceed205°C [400°F] for thicknesses up to 40 mm [1-1/2 in]inclusive, and 230°C [450°F] for greater thicknesses.For HPS 485W [HPS 70W], the maximum preheat andinterpass temperature shall be 230°C [450°F] for allthicknesses.

4.2.3 Temperature controls shall be based upon the thick-ness and grades of the base metal. For combinations ofbase metals, preheat and interpass temperatures shall bebased upon the higher of the required temperatures.

4.2.4 Thick material, or highly restrained joints or repairwelds, shall be preheated by the Contractor above theminimum specified temperatures as required to preventcracking or minimize lamellar tearing.

4.2.5 The maximum WPS preheat temperature shall be230°C [450°F], unless otherwise approved by the Engineer.

4.2.6 Welding shall not be done when the ambient tem-perature in the immediate vicinity of the weld is lowerthan –20°C [0°F]. The ambient environmental tempera-ture may be lower than –20°C [0°F], provided supple-mental heat and protection from the elements aresufficient to maintain a temperature adjacent to the weld-ment at –20°C [0°F], or higher.

4.2.7 When the base metal is below the temperaturelisted for the welding process being used and the thick-ness of material being welded, it shall be preheated(except as otherwise provided) in such a manner that thesteel on which weld metal is being deposited is at orabove the specified minimum temperature for a distanceequal to the thickness of the part being welded, but notless than 75 mm [3 in] in all directions from the point ofwelding. To increase the effectiveness of preheat withoutincreasing the temperature, at the Contractor’s option,the area and depth that is heated may be increasedbeyond the minimum specified. There shall be no limit tothe maximum area that may be preheated unless stated inthe contract documents.

4.2.8 When the base-metal temperature is below 0°C[32°F], the base metal shall be heated to at least 20°C[70°F], and this minimum temperature shall be main-tained during welding.

4.2.9 The minimum preheat and interpass temperaturerequirements for SAW made with parallel or multiple

PART A

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67

electrodes may be modified under the provisions of4.10.6 or 4.11.6.

4.3 Heat Input Control for Grade 690 [100] and 690W [100W]

When M270M [M270] Grade 690/690W [100/100W](A 709M [A 709] Grades 690/690W [100/100W]) steelsare welded, welding heat input shall be appropriate forthe thickness of steel to be joined and the preheat andinterpass temperature used. Heat input shall not exceedthe manufacturers’ recommendations. Table 12.5 may beused for guidance in welding Grade 690/690W [100/100W] steels.

4.4 Stress Relief Heat Treatment4.4.1 Where required by the contract drawings or specifi-cations, welded assemblies shall be stress-relieved byheat treating. Finish machining shall preferably be doneafter stress relieving. Thermal stress relieving ofweldments involving M270M [M270] Grades 690/690W[100/100W] is prohibited unless required to maintaindimensional stability or avoid stress corrosion-inducedcracking. If heat treatment is required for tension ele-ments, the contract may require prototype testing withsimilar configurations to evaluate effects on HAZ graingrowth, ductility, and toughness.

4.4.2 The stress relief treatment shall conform to the fol-lowing requirements:

4.4.2.1 The temperature of the furnace shall notexceed 315°C [600°F] at the time the welded assembly isplaced in it.

4.4.2.2 Above 315°C [600°F] the rate of heating in°C/hr shall not exceed 5600 divided by the maximummetal thickness in mm (in °F/hr the rate of heating shallnot exceed 400°F per hour divided by the maximummetal thickness in inches), but not more than 220°C[400°F]/hr. During the heating period, variation in tem-perature throughout the portion of the part being heatedshall be no greater than 140°C [250°F] within any 5 m[15 ft] interval of length.

NOTE: The rates of heating and cooling need not be lessthan 55°C [100°F] per hour. However, in all cases, con-sideration of closed chambers and complex structures mayindicate reduced rates of heating and cooling to avoidstructural damage due to excessive thermal gradients.

4.4.2.3 After a maximum temperature of 600°C[1100°F] is reached on quenched and tempered steels, ora mean temperature range between 600°C [1100°F] and

650°C [1200°F] is reached on other steels, the tempera-ture of the assembly shall be held within the specifiedlimits for a time not less than specified in Table 4.5,based on weld thickness. When the specified stress reliefis for dimensional stability, the holding time shall not beless than specified in Table 4.5, based on the thickness ofthe thicker part. During the holding period, the highestand lowest temperature throughout the portion of theassembly being heated shall not vary by greater than85°C [150°F].

4.4.2.4 Above 315°C [600°F], cooling shall occur in aclosed furnace or cooling chamber at a rate in °C/hr notexceeding 7000 divided by the maximum metal thick-ness in mm (in °F/hr the cooling rate shall be no greaterthan 500°F per hour divided by the maximum metalthickness in inches), but not more than 280°C[500°F]/hr. Below 315°C [600°F], the assembly may becooled in still air.

4.4.3 Alternatively, when it is impractical to postweldheat treat to the temperature limitations described in4.4.2, welded assemblies may be stress-relieved at lowertemperatures for longer periods of time, as given inTable 4.6.

Part BShielded Metal Arc Welding (SMAW)

4.5 Electrodes for SMAW4.5.1 Electrodes for SMAW shall conform to the require-ments of the latest edition of AWS A5.1/A5.1M, Specifi-cation for Covered Carbon Steel Arc Welding Electrodes,or to the requirements of AWS A5.5/ A5.5M, Specifica-tion for Low-Alloy Steel Covered Arc Welding Electrodes.All electrodes for SMAW shall be of the low-hydrogenclassification.

4.5.2 All electrodes having low hydrogen coverings con-forming to AWS 5.1/A5.1M shall be purchased in her-metically sealed containers or shall be dried inconformance with the manufacturer’s written dryinginstructions. Electrodes having a low-hydrogen coveringconforming to AWS A5.5/A5.5M shall be purchased inhermetically sealed containers or shall be dried at leastone hour at temperatures between 370°C [700°F] and425°C [800°F] before being used. Electrodes shall bedried prior to use if the hermetically sealed containershows evidence of damage. Immediately after opening ofthe hermetically sealed container or removal of the elec-trodes from drying ovens, electrodes shall be stored inovens held at a temperature of at least 120°C [250°F].

PARTS A & B


68

After the opening of hermetically sealed containers orremoval from drying or storage ovens, electrode expo-sure to the atmosphere shall not exceed the requirementsof 4.5.2.1.

4.5.2.1 Electrodes exposed to the atmosphere uponremoval from drying or storage ovens or hermeticallysealed containers shall be used within the time limitshown in Table 4.7 or redried at 230°C [450°F] to 290°C[550°F] for two hours minimum, except as provided in4.5.2.3.

4.5.2.2 Electrodes exposed to the atmosphere for peri-ods less than those allowed by Table 4.7 may be returnedto a holding oven maintained at 120°C [250°F] minimumand after a minimum period of four hours at that temper-ature may be reissued. The provisions of 4.5.4 shallapply.

4.5.2.3 Optional Supplemental Moisture-ResistantDesignators. Electrodes with the AWS filler metal spec-ifications optional supplemental moisture resistance des-ignator “R” may be exposed to the atmosphere for up tonine hours when welding steels with a minimum speci-fied yield strength of 345 MPa [50 ksi] or less. Moisture-resistant electrodes shall be received in containers thatbear the additional designator “R” as part of the AWSclassification.

4.5.3 When used for welding M270M [M270] Grades690/690W [100/100W] (A 709M [A 709] Grades 690/690W [100/100W]) steels, electrodes shall be dried atleast one hour at temperatures between 370°C [700°F]and 425°C [800°F] before being used, whether furnishedin hermetically sealed containers or otherwise.

4.5.4 Electrodes that conform to the provisions of 4.5.2shall be redried no more than one time. Electrodes thathave been wet shall not be used.

4.5.5 The Contractor shall furnish certified copies of testreports of all pertinent tests required of AWS A5.1/A5.1M or of AWS A5.5/A5.5M, whichever is applicable,made on electrodes of the same class, size, and brand, andwhich were manufactured by the same process and thesame materials as the electrodes being used on the project(see 4.12.3). The test shall have been made within oneyear prior to the manufacture of the electrodes furnished.For sizes of electrodes for which tests are not required byAWS A5.1/A5.1M or AWS A5.5/A5.5M, the test reportsfor electrodes of the size nearest to the size being deliv-ered and of the same classification shall be furnished. Thereport shall include the manufacturer’s certification thatthe process and material requirements were the same formanufacturing the tested electrodes and the furnishedelectrodes. A recommended form for the reporting of elec-trode tests is shown in Annex L, Form L1.

4.5.6 In lieu of requiring a Contractor to furnish copiesof manufacturer’s test reports for each shipment ofelectrodes on a project, the contracting authority maymaintain a list of approved brands of electrodes forwhich satisfactory reports of tests made within one yearhave been previously submitted. If this alternative iselected, the list shall be available to project Engineersand Contractors.

4.6 Procedures for SMAW4.6.1 The work shall be positioned for flat position weld-ing whenever practical.

4.6.2 The classification and size of electrode, arc length,voltage, and amperage shall be suited to the thickness ofthe material, type of groove, welding positions, and othercircumstances attending the work. Welding current shallbe within the range recommended by the electrodemanufacturer.

4.6.3 The maximum diameter of electrodes shall be asfollows:

(1) 6.4 mm [1/4 in] for all welds made in the flatposition, except root passes

(2) 6.4 mm [1/4 in] for horizontal fillet welds

(3) 6.4 mm [1/4 in] for root passes of fillet weldsmade in the flat position and groove welds made in theflat position with backing and with a root opening of 6mm [1/4 in] or more

(4) 4.0 mm [5/32 in] for welds made in the verticaland overhead position

(5) 5.0 mm [3/16 in] for root passes of groove weldsand for all other welds not included under 4.6.3(1), (2),(3), and (4)

4.6.4 The minimum size of a root pass shall be sufficientto prevent cracking.

4.6.5 The maximum thickness of root passes in groovewelds shall be 6 mm [1/4 in].

4.6.6 The maximum size of single-pass fillet welds androot passes of multiple-pass fillet welds shall be as fol-lows:

(1) 10 mm [3/8 in] in the flat position

(2) 8 mm [5/16 in] in the horizontal or overheadpositions

(3) 12 mm [1/2 in] in the vertical position

PART B


69

4.6.7 The maximum thickness of layers subsequent toroot passes of groove and fillet welds shall be as follows:

(1) 3 mm [1/8 in] for subsequent layers of weldsmade in the flat position

(2) 5 mm [3/16 in] for subsequent layers of weldsmade in the vertical, overhead, or horizontal positions

4.6.8 The progression for all passes in the vertical posi-tion shall be upward, unless a downward progression isqualified by tests approved by the Engineer.

4.6.9 CJP groove welds made without the use of steelbacking shall have the root gouged to sound metal beforewelding is started from the second side.

Part CSubmerged Arc Welding (SAW)

4.7 General Requirements4.7.1 SAW may be performed with one or more singleelectrodes, one or more parallel electrodes, or combina-tions of single and parallel electrodes. The spacingbetween arcs shall be such that the slag cover over theweld metal produced by a leading arc does not cool suffi-ciently to prevent the proper weld deposit of a followingelectrode. SAW with multiple electrodes may be used forany groove or fillet weld pass.

4.7.2 The following subclauses (4.7.3–4.7.8) shall gov-ern the use of SAW for any as-rolled or normalized steelapproved for welding by this code. When weldingquenched and tempered steels, it is necessary to complywith the steel producer’s recommendations for maximumallowable combinations of heat input and preheat. Suchconsiderations shall include the additional heat input pro-duced during the simultaneous welding of two sides of acommon member.

4.7.3 The diameter of electrodes shall not exceed 6.4 mm[1/4 in].

4.7.4 Surfaces on which SAW are to be deposited andadjacent faying surfaces shall be clean and free of mois-ture as specified in 3.2.1.

4.7.5 When the joint to be welded requires specific rootpenetration and is not backgouged, the Contractor shallprepare a sample joint and macroetched cross section todemonstrate that the proposed WPS will attain therequired root penetration. The Engineer may accept aradiograph of a test joint or recorded evidence in lieu of

the test specified in this subclause. (The Engineer shouldaccept properly documented evidence of previous quali-fication tests.)

4.7.6 Roots of groove welds may be made against fusedsteel backing or approved unfused backing. Roots of fil-let welds may be supported by backing to prevent melt-ing-through of the base metal. All backing shall conformto the requirements of 3.13.

4.7.7 Neither the depth nor the maximum width in thecross section of weld metal deposited in each weld passshall exceed the width at the surface of the weld pass (seeFigure 4.1). This requirement may be waived only if thetesting of a WPS to the satisfaction of the Engineer hasdemonstrated that such welds exhibit freedom fromcracks, and the same WPS and electrode-flux combina-tions are used in construction.

4.7.8 Tack welds (in the form of fillet welds) 8 mm[5/16 in] or smaller, may remain in the roots of jointsrequiring specific root penetration, but shall not produceobjectionable changes in the appearance of the weldsurface nor result in decreased penetration. Tack weldsnot conforming to the preceding requirements shall beremoved or reduced in size by any suitable means beforewelding. Tack welds in the root of a joint with steelbacking less than 8 mm [5/16 in] thick shall be removedor made continuous for the full length of the joint, usingSMAW with low-hydrogen electrodes.

4.8 Electrodes and Fluxes for SAW4.8.1 Bare electrodes and flux used in combination forSAW of steels shall conform to the requirements of thelatest edition of AWS A5.17/A5.17M, Specification forCarbon Steel Electrodes and Fluxes for Submerged ArcWelding, or to the requirements of the latest edition ofAWS A5.23/A5.23M, Specification for Low Alloy SteelElectrodes and Fluxes for Submerged Arc Welding.

4.8.2 Certification

4.8.2.1 The Contractor shall furnish certified copies oftest reports for all electrode and flux combinations usedon a project in conformance with these filler metal speci-fications (see 4.12.3). The report shall include the resultof all pertinent required tests of AWS A5.17/A5.17M orAWS A5.23/A5.23M made on the same classification orgrade of electrode/flux combination being used on theproject. The test shall have been made on electrodes ofthe same classification in combination with flux of thesame brand and composition, and made with the samemanufacturing procedure, as the materials furnished. Thetest may have been for process qualification or quality

PARTS B & C


70

control and shall have been made within one year prior tothe manufacture of the electrode furnished. The testreport form shall be similar to that shown in Annex L,Form L1, containing all pertinent information concern-ing the test required by the specification (see 4.5.5).

4.8.2.2 In lieu of requiring a Contractor to furnishcopies of manufacturer’s test reports for each shipmentof electrode and flux on a project, the contracting author-ity may maintain a list of approved brands of electrode/flux combinations for which satisfactory test reports madewithin one year have been previously submitted. If thisalternative is elected, the list shall be available to projectEngineers and Contractors.

4.8.3 Flux used for SAW shall be dry and free of contam-ination from dirt, mill scale, or other foreign material.All flux shall be purchased in packages that can bestored, under normal conditions, for at least six monthswithout such storage effecting its welding characteristicsor weld properties. Flux from damaged packages shall bediscarded or shall be dried at a minimum temperature of260°C [500°F] for one hour before use.

Flux shall be placed in the dispensing system immedi-ately upon opening a package, or, if used from an openpackage, the flux shall be dried or the top 25 mm [1 in]shall be discarded. All flux in hoppers and other deliverysystems open to the atmosphere shall be removed andreplaced with new, or freshly dried flux, whenever weld-ing operations have not been conducted for more than24 hours. All flux in pressurized tanks, flux recoverysystems, and other delivery systems closed to the atmo-sphere shall be removed and replaced with new orfreshly dried flux, whenever welding operations have notbeen conducted for more than 96 hours. Flux that hascome in direct contact with water shall not be used.

4.8.4 SAW flux that has not been melted during thewelding operation may be reused after recovery by vacu-uming, use of catch pans, sweeping from weldment sur-faces or other means. Recovered flux shall be passedthrough an appropriate screen and over a suitable magnetto remove unwanted particles and materials before beingreturned to the flux supply system. Flux that is notreclaimed from weldment surfaces within one hour ofbeing deposited on the weld shall be dried before beingused as provided in 4.8.3.

The Contractor shall have a system for collectingunmelted flux, mixing with new flux as required, andwelding with a mixture of these two such that the fluxcomposition and particle size distribution at the arc arerelatively constant. Flux fused in welding shall not bereused.

4.9 Procedures for SAW with a Single Electrode

4.9.1 Single electrode shall be defined as one electrodeconnected exclusively to one power source which mayconsist of one or more power units.

4.9.2 All submerged arc welds except fillet welds shallbe made in the flat position. Fillet welds may be made ineither the flat or horizontal position, except that singlepass fillet welds made in the horizontal position shall notexceed 8 mm [5/16 in] size.

4.9.3 The thickness of weld layers, except root and sur-face layers, shall not exceed 6 mm [1/4 in]. When theroot opening is 12 mm [1/2 in] or greater, a multiple-pass, split-layer technique shall be used. The split-layertechnique shall also be used in making multiple-passwelds when the width of the layer exceeds 16 mm [5/8 in].

4.9.4 The welding current, arc voltage, and speed oftravel shall be such that each pass will have completefusion with the adjacent base metal and weld metal, andthere shall be no overlap or undue undercutting. Themaximum welding current to be used in making a grooveweld for any pass that has fusion to both faces of thegroove shall be 600 A, except that the final layer may bemade using a higher current. The maximum current to beused for making fillet welds in the flat position shall be1000 A.

4.10 Procedures for SAW with Parallel Electrodes

4.10.1 Parallel electrodes shall be defined as two elec-trodes connected electrically in parallel exclusively tothe same power source. Both electrodes are usually fedby means of a single electrode feeder. Welding current,when specified, shall be the total for the two electrodes.

4.10.2 SAW with parallel electrodes, except fillet welds,shall be made in the flat position. Fillet welds may bemade in either the flat or horizontal position, except thatsingle-pass parallel electrode fillet welds made in thehorizontal position shall not exceed 8 mm [5/16 in] size.

4.10.3 The thickness of weld layers shall not be limited.In making the root pass of a groove weld, single or paral-lel electrodes may be used. Backing or root faces shall beof adequate thickness to prevent melting-through.

When the width of a surface in a groove on which a layerof weld metal is to be deposited exceeds 12 mm [1/2 in],parallel electrodes shall be displaced laterally or a split-layer technique shall be used to assure adequate cornerfusion. When the width of a previously deposited layer

PART C


71

exceeds 16 mm [5/8 in], a split-layer technique withelectrodes in tandem shall be used.

4.10.4 The welding current, arc voltage, speed of travel,and relative location of electrodes shall be such that eachpass will have complete fusion with the adjacent basemetal, and such that there will be no depressions orundue undercutting at the toe of the weld. Excessive con-cavity of initial passes shall be avoided to prevent crack-ing in the roots of joints under restraint.

4.10.4.1 The maximum welding current in making agroove weld shall be the following:

(1) 700 A for parallel electrodes when making theroot layer in a groove having no root opening, and whichdoes not fill the groove

(2) 900 A for parallel electrodes when making theroot pass in a groove having steel backing or a root faceof sufficient thickness to prevent melt-through

(3) 1200 A for parallel electrodes for all passesexcept the final layer

(4) For the final layer, no restriction on welding cur-rent qualified by test under the provisions of 5.12 or 5.13

4.10.4.2 The maximum welding current to be used inmaking a fillet weld shall be 1200 A for parallelelectrodes.

4.10.5 Welds may also be made in the root of groove orfillet welds using GMAW, followed by parallel sub-merged arcs, provided that the GMAW conforms to therequirements of Part D of this section, and providing thespacing between the gas shielded arc and the followingsubmerged arc does not exceed 400 mm [15 in].

4.10.6 Preheat and interpass temperatures for parallelelectrode SAW shall be selected in conformance with theprovisions of 4.2. For single-pass groove or fillet welds,for combinations of metals being welded and the heatinput involved, and with the approval of the Engineer,preheat and interpass temperatures may be establishedwhich are sufficient to reduce the hardness in the HAZ ofthe base metal to less than 225 Vickers hardness numberfor steel having a minimum specified tensile strength notexceeding 415 MPa [60 ksi], and to less than 280 Vick-ers hardness number for steel having a minimum speci-fied tensile strength greater than 415 MPa [60 ksi], butnot exceeding 485 MPa [70 ksi].

The Vickers hardness number shall be determined inconformance with ASTM E 92. If another method ofhardness is to be used, the equivalent hardness numbershall be determined from ASTM E 140, and testingshall be performed according to the applicable ASTMspecification.

4.10.6.1 When required by 4.10.6, hardness of theHAZ shall be determined by the following:

(1) On the initial macroetch cross section of a sampletest specimen.

(2) On the surface of the member during the progressof the work. The surface shall be ground prior to hard-ness testing.

(a) The frequency of such HAZ testing shall be atleast one test area per weldment of the thicker base metalinvolved in a joint for each 15 m [45 ft] of groove weldsor pair of fillet welds.

(b) These hardness determinations may be discon-tinued after the procedure has been established to the sat-isfaction of the Engineer.

4.10.6.2 Reduction of the preheat requirements of 4.2shall be prohibited for fillet welds 10 mm [3/8 in] andunder in size.

4.11 Procedures for SAW with Multiple Electrodes

4.11.1 Multiple electrodes shall be defined as the combi-nation of two or more single or parallel electrode sys-tems. Each of the component systems shall have its ownindependent power source and its own electrode feeder.

4.11.2 SAW with multiple electrodes, except fillet welds,shall be made in the flat position. Fillet welds may bemade in either the flat or horizontal position, except thatsingle-pass multiple electrode fillet welds made in thehorizontal position shall not exceed 12 mm [1/2 in].

4.11.3 The thickness of weld layers shall not be limited.In making the root pass of a groove weld, single or multi-ple electrodes may be used. Backing or root faces shallbe of adequate thickness to prevent melt-through. Whenthe width of a surface in a groove on which a layer ofweld metal is to be deposited exceeds 12 mm [1/2 in], asplit-layer technique shall be used to assure adequatecorner fusion. When the width of a previously depositedlayer exceeds 25 mm [1 in], and only two electrodes areused, a split-layer technique with electrodes in tandemshall be employed.

4.11.4 The welding current, arc voltage, speed of travel,and relative location of electrodes shall be such that eachpass shall have complete fusion with the adjacent basemetal and weld metal and such that there will be nodepressions or undue undercutting at the toe of the weld.Excessive concavity of initial passes shall be avoided toprevent cracking in roots of joints under restraint.

PART C


72

4.11.4.1 The maximum welding current in making agroove weld shall be the following:

(1) 700 A for any single electrode or for parallel elec-trodes when making the root layer in a groove having noroot opening and which does not fill the groove

(2) 750 A for any single electrode or 900 A for paral-lel electrodes when making the root pass in a groove hav-ing steel backing or a root face with sufficient thicknessto prevent melt-through

(3) 1000 A for any single electrode or 1200 A forparallel electrodes for all other passes except the finallayer

(4) For the final layer there is no restriction on weld-ing current qualified by test under the provisions of 5.12or 5.13.

4.11.4.2 The maximum welding current to be used inmaking a fillet weld shall be 1000 A for any single elec-trode or 1200 A for parallel electrodes.

4.11.5 Multiple electrode welds may also be made in theroot of groove or fillet welds using GMAW followed bymultiple submerged arcs, provided that the GMAWconforms to the requirements of Part D of this clause,and provided the spacing between the gas shielded arcand the first following submerged arc does not exceed400 mm [15 in].

4.11.6 Preheat and interpass temperatures for multipleelectrode SAW shall be selected in conformance with4.2. For single-pass groove or fillet welds, for combina-tions of metals being welded and the heat input involved,and with the approval of the Engineer, preheat and inter-pass temperatures may be established which are suffi-cient to reduce the hardness in the HAZ of the base metalto less than 225 Vickers hardness number for steel hav-ing a minimum specified tensile strength not exceeding415 MPa [60 ksi], and to less than 280 Vickers hardnessnumber for steel having a minimum specified tensilestrength greater than 415 MPa [60 ksi] but not exceeding485 MPa [70 ksi].

4.11.6.1 When required by 4.11.6, hardness of theHAZ shall be determined:

(1) On the initial macroetch cross sections of a sam-ple test specimen, and

(2) On the surface of the member during the progressof the work. The surface shall be ground prior to hard-ness testing.

(a) The frequency of such HAZ testing shall be atleast one test area per weldment on the thicker base metalinvolved in a joint for each 15 m [45 ft] of groove weldsor pair of fillet welds.

(b) These hardness determinations may be discon-tinued after the procedure has been established to the sat-isfaction of the Engineer.

4.11.6.2 Reduction of the preheat requirements of 4.2shall be prohibited for fillet welds 10 mm [3/8 in] andunder in size.

Part DGas Metal Arc Welding (GMAW) and

Flux Cored Arc Welding (FCAW)

4.12 Electrodes4.12.1 The electrodes and shielding for GMAW orFCAW for producing weld metal with minimum speci-fied yield strengths of 415 MPa [60 ksi] or less, shallconform to the requirements of the latest edition of AWSA5.18/A5.18M, Specification for Carbon Steel FillerMetals and Rods, AWS A5.20/A5.20M, Specification forCarbon Steel Electrodes for Flux Cored Arc Welding, orAWS A5.29/A5.29M, Specification for Low-Alloy SteelElectrodes for Flux Cored Arc Welding, as applicable.

4.12.2 Weld metal having a minimum specified yieldstrength greater than 415 MPa [60 ksi] shall conform tothe following requirements:

4.12.2.1 The electrodes and shielding gas for GMAWshall conform to the latest edition of AWS A5.28/A5.28M, Specification for Low Alloy Steel Filler Metalsfor Gas Shielded Arc Welding.

4.12.2.2 The electrodes and shielding gas (if required)for FCAW shall conform to the latest edition of AWSA5.29/A5.29M.

4.12.3 The Contractor shall furnish certificates of con-formance for all electrodes and combinations of shield-ing used on a project in conformance with this code. Thereport shall include the results of all pertinent requiredtests of AWS A5.18/A5.18M, AWS A5.28/A5.289M,AWS A5.20/A5.20M, or AWS A5.29/A5.29M, which-ever is applicable, made on electrodes of the same classi-fication or grade, of the same brand, welded with thesame shielding gas, and manufactured with the same pro-cess and same materials as electrodes being used on thisproject. Tests may have been for process qualification orquality control and shall have been made within one yearprior to manufacture of the electrodes furnished. Thereport shall include the manufacturer’s certification thatthe process and material requirements were the same formanufacturing the tested electrodes and the furnishedelectrodes. The test report shall be similar to that shown in

PARTS C & D


73

Annex L, Form L-1, containing all pertinent informationconcerning the test required by the electrode specification.

4.12.4 In lieu of requiring a Contractor to furnish copiesof manufacturer’s test reports for each shipment of elec-trodes on a project, the contracting authority may main-tain a list of approved brands of electrodes for whichsatisfactory tests made within one year have been previ-ously submitted. If this alternative is elected, the list shallbe available to project Engineers and Contractors.

4.13 Shielding GasA gas or gas mixture used for shielding in GMAW orwhen required for FCAW shall conform to the require-ments of the latest edition of AWS A5.32/A5.32M, Spec-ification for Welding Shielding Gases. When requestedby the Engineer, the Contractor or fabricator shall fur-nish the gas manufacturer’s certification that the gas orgas mixture is suitable for the intended application andshall meet the dew point requirement.

4.14 Procedures for GMAW and FCAW with a Single Electrode

4.14.1 The following are general requirements:

4.14.1.1 Electrodes shall be dry and in suitable condi-tion for use.

4.14.1.2 The maximum electrode diameter shall be4.0 mm [5/32 in] for the flat and horizontal positions,2.4 mm [3/32 in] for the vertical position, and 2.0 mm[5/64 in] for the overhead position.

4.14.1.3 The maximum size of a fillet weld made inone pass shall be 12 mm [1/2 in] for the flat and verticalpositions, 10 mm [3/8 in] for the horizontal position, and8 mm [5/16 in] for the overhead position.

4.14.1.4 GMAW. The thickness of weld layers ingroove welds, except root and surface layers, shall notexceed 6 mm [1/4 in]. When the root opening is 12 mm[1/2 in] or greater, a multiple-pass split-layer techniqueshall be used. The split-layer technique shall also be usedin making all multiple-pass welds when the width of thelayer exceeds 16 mm [5/8 in].

4.14.1.5 FCAW. The thickness of the weld layers ingroove welds, except root and surface layers, shall notexceed 6 mm [1/4 in]. When the root opening is 12 mm[1/2 in] or greater, a multiple-pass split-layer techniqueshall be used. When the width of a layer of a groove weldin the flat, horizontal, or overhead position is 16 mm[5/8 in] or greater, a multiple-pass split-layer technique

shall be used. When welding in the vertical position, asplit-layer technique shall be used when the width of thelayer exceeds 25 mm [1 in].

4.14.1.6 The welding current, arc voltage, gas flow,mode of metal transfer, and speed of travel shall be suchthat each pass has complete fusion with adjacent basemetal and weld metal, and there is no overlap or exces-sive porosity or undercutting.

4.14.1.7 The progression for all passes of verticalposition welding shall be upwards, unless a downwardprogression shall be qualified by tests approved by theEngineer.

4.14.2 CJP groove welds made without the use of back-ing shall have the root of the initial weld gouged,chipped, or otherwise removed to sound weld metalbefore welding is started from the second side.

4.14.3 GMAW, or FCAW-G, shall not be done in a draftor wind unless the weld is protected by a shelter. Suchshelter shall be of material and shape appropriate toreduce wind velocity in the vicinity of the weld to a max-imum of 10 km/hr [5 mph].

4.14.4 GMAW-S shall not be used in the constructionof bridge members without the written approval of theEngineer (see Annex K for informative guidelines indetermining GMAW-S).

Part EElectroslag Welding (ESW) and

Electrogas Welding (EGW)

4.15 Qualification of Process, WPSs, and Joint Details

4.15.1 Prior to use, the Contractor shall prepare and qual-ify each WPS to be used according to the requirements in5.13. The WPS shall include the joint details, filler metaltype and diameter, amperage, voltage (type and polarity),speed of vertical travel if not an automatic function of arclength or deposition rate, oscillation (traverse speed,length, and dwell time), type of shielding including flowrate and dew point of gas (if required), or type of flux,type of molding shoe, postweld heat treatment if used,and other pertinent information.

4.15.2 The ESW and EGW processes shall not be usedfor welding quenched and tempered steel nor for weldingcomponents of members subject to tensile stresses orreversal of stress.

PARTS D & E


74

4.16 Mechanical Properties

WPS qualification testing under the provisions of 5.13shall verify that weld metal mechanical properties meetthe requirements of Table 4.2.

4.17 Condition of Electrodes and Guide Tubes

Electrodes and consumable guide tubes shall be dry,clean, and in suitable condition for use.

4.18 Shielding Gas

A gas or gas mixture when required for shielding ofEGW shall conform to the requirements of the latest edi-tion of AWS A5.32/A5.32M, Specification for WeldingShielding Gases. When requested by the Engineer, theContractor or fabricator shall furnish the gas manufac-turer’s certification that the gas or gas mixture is suitablefor the intended application and will meet the dew pointrequirements.

4.19 Condition of Flux

Flux used for ESW shall be dry and free of contamina-tion from dirt, mill scale, or other foreign material. Allflux shall be purchased in packages that can be stored,under normal conditions, for at least six months withoutsuch storage affecting its welding characteristics or weldproperties. Flux from packages damaged in transit or inhandling shall be discarded or shall be dried in conform-ance with the flux manufacturer’s written drying instruc-tions. Flux that has been wet shall not be used.

4.20 Procedures for ESW and EGW

4.20.1 Gas to be used for shielding shall be of a weldinggrade and shall meet all requirements of the WPS. Whenmixed at the welding site, suitable meters shall be usedfor proportioning the gases. Percentage of gases shallconform to the requirements of the WPS.

4.20.2 EGW that requires external gas shielding shall notbe done in a draft or wind of a velocity greater than10 km/hr [5 mph] unless the weld is protected by a shel-ter. This shelter shall be of a material and shape appro-priate to reduce wind velocity in the vicinity of the weldsurface to a maximum of 10 km/hr [5 mph].

4.20.3 The type and diameter of the electrodes used shallmeet the requirements of the WPS. Electrodes shall con-form to the requirements of Table 4.2.

4.20.4 Welds shall be started in such a manner as toallow sufficient heat buildup for complete fusion of theweld metal to the groove faces of the joint before theweld leaves the sump. Welds which have been stopped atany point in the weld joint for a sufficient amount of timefor the slag or weld pool to begin to solidify may berestarted and completed, provided the completed weld isproven satisfactory after examination by UT for a mini-mum of 150 mm [6 in] on either side of the restart and,unless prohibited by joint geometry, the weld soundnessshall also be confirmed by RT. All such restart locationsshall be recorded and reported to the Engineer.

4.20.5 Because of the high heat input characteristic ofthese processes, preheating shall not normally berequired. However, no welding shall be performed whenthe temperature of the base metal at the point of weldingis below 0°C [32°F]. Preheating may be required by theWPS to improve the quality of the weld at the startingsump.

4.20.6 All groove welds in butt joints in main membersshall be radiographed in conformance with the pro-visions of Clause 6, Part B, and shall conform to therequirements of 6.26 and Figure 6.8.

4.20.7 Welds having discontinuities prohibited by 6.26shall be repaired as allowed by 3.7 using a qualifiedwelding process or the entire weld shall be removed andreplaced.

Part FPlug and Slot Welds

4.21 Plug WeldsThe technique used to make plug welds when usingSMAW, GMAW (except GMAW-S), and FCAW pro-cesses shall be as follows:

4.21.1 For welds to be made in the flat position, eachweld shall be deposited around the root of the joint andthen deposited along a spiral path to the center of thehole, fusing and depositing a layer of weld metal in theroot and bottom of the joint. The arc is then carried to theperiphery of the hole and the procedure repeated, fusingand depositing successive layers to fill the hole to therequired depth. The slag covering the weld metal shouldbe kept molten until the weld is finished. If the arc is

PARTS E & F


75

broken or the slag is allowed to cool, the slag shall becompletely removed before restarting the weld.

4.21.2 For welds to be made in the vertical position, thearc shall be started at the root of the joint at the lowerside of the hole and shall be carried upward, fusing intothe face of the inner plate and to the side of the hole. Thearc shall be stopped at the top of the hole, the slag shallbe cleaned off, and the process shall be repeated on theopposite side of the hole. After cleaning slag from theweld, other layers should be similarly deposited to fillthe hole to the required depth.

4.21.3 For welds to be made in the overhead position, aspiral procedure shall be followed as for the flat position,except that the slag should be allowed to cool and shouldbe completely removed after depositing each successivelayer until the hole shall be filled to the required depth.

4.22 Slot Welds

Slot welds shall be made using techniques similar tothose specified in 4.21 for plug welds, except that if thelength of the slot exceeds three times the width, or if theslot extends to the edge of the part, the technique require-ments of 4.21.3 shall apply.

4.23 Plug and Slot Welds

When plug and slot welds are made by continuous weld-ing over previously deposited weld beads and throughmolten slag, the welder shall observe the arc and slagcover for signs of conditions that are present during theformation of fusion discontinuities, such as intermittentarc, excessive spatter, and slag boiling with excessivegas. When these signs are observed, the welding shall bediscontinued. After the slag has cooled, all slag andfusion defects shall be removed before welding isresumed.

Part GControl of Production

Welding Variables

4.24 TestsControl of welding variables shall be based upon theresults of WPS qualification tests performed as describedin Clause 5.

4.25 Control of VariablesWelders and welding operators shall set welding con-trols, weld, and operate welding equipment within thelimitations on current, voltage, travel speed, and shield-ing gas flow rates described in the approved WPS.

4.26 Calibration of Equipment4.26.1 Equipment used to measure variables shall beaccurately calibrated. The Contractor shall verify, at leastevery 3 months, the accuracy of meters and other devicesused to record or display welding variables. The equip-ment used for verifying meters and other devices shall becertified annually.

4.26.2 Correction charts or similar methods may be usedto compensate for meter error when approved by theEngineer.

4.27 Current Control4.27.1 The welding current may be controlled by control-ling the wire feed speed, provided correlation betweenamperage and wire feed speed is known for specific elec-trode types and diameters.

4.27.2 The Inspector shall have access to accurate amper-age versus wire feed speed tables or charts wheneverwire feed speed is used as a method of current control.

PARTS F & G

76


Table 4.1Matching Filler Metal Requirements for WPSs Qualified in Conformance with 5.12

Base Metal

AWS Electrode Specification

Qualification, Pretest, and Verification Test Requirement

AASHTO(ASTM) Designation

MinimumYield

Strength,MPa [ksi]

Minimum Tensile

Strength,MPa [ksi]

Minimum Elongation in 50 mm[2 in], %

CVN, J [ft∙lb] AASHTOTemperature Zones

I and II III

M270M [M270] (A 709M [A 709]) Gr. 250 [36]

SMAWAWS A5.1/A5.1ME6018, E7015, E7016, E7018, E7018-1, E7018M, E7028A5.5/A5.5ME7015-X, E7016-X, E7018-XE7015, -16, -18-C1L, -C2L, E7018-C3LE8016, -18-C1, -C2E8016, -18-C3, -C4

Prequalified—Exempt from Test (see 5.11)

SAWAWS A5.17/A5.17MF6A0-EXXXF6A0-ECXF7A0-EXXXF7A0-ECXAWS A5.23/A5.23MF7A0-EXXX-XXF7A0-ECXXX-XXF8A0-EXXX-XXF8A0-ECXXX-XX

300 [45] 400 [60] 22 27 @ –20°C[20 @ 0°F]

27 @ –30°C[20 @ –20°F]

FCAW-GAWS A5.20/A5.20ME7XT-1C, -1ME7XT-5C, -5ME7XT-9C, -9ME7XT-12C, -12MAWS A5.29/A5.29ME6XT1-NiC, -NiME7XT1-XC, -XME7XT5-XC, -XME8XT1-NiXC, -NiXME8XT5-NiXC, -NiXME8XT1-W2C, -W2M

300 [45] 400 [60] 22 27 @ –20°C[20 @ 0°F]

27 @ –30°C[20 @ –20°F]

GMAWAWS A5.18/A5.18ME70C-3C, E70C-3M,E70C-6C, E70C-6MAWS A5.28/A5.28ME70C-XXXE80C-NiXE80C-W2

300 [45] 400 [60] 22 27 @ –20°C[20 @ 0°F]

27 @ –30°C[20 @ –20°F]

(Continued)

77


M270M [M270](A 709M [A 709])Gr. 345 [50]Type 1, 2, or 3,Gr. 345W [50W]Gr. HPS 345W [HPS 50W]100 mm [4 in]and under

SMAWAWS A5.1/A5.1ME7015, E7016, E7018, E7018-1, E7018M, E7028A5.5/A5.5ME7015-X, E7016-X, E7018-XE7015, -16-C1L, -C2LE7018-C1L, -C2L, -C3LE8016, -18-C1, -C2E8016, -18-C3, -C4E7018-W1, E8018-W2


SAWAWS A5.17/A5.17M F7A0-EXXXF7A0-ECXAWS A5.23/A5.23MF7A0-EXXX-XXF7A0-ECXXX-XXF8A0-EXXX-XXF8A0-ECXXX-XX

345 [50] 450 [65] 22 27 @ –20°C[20 @ 0°F]

27 @ –30°C[20 @ –20°F]

FCAW-GAWS A5.20/A5.20ME7XT-1C, -1ME7XT-5C, -5ME7XT-9C, -9ME7XT-12C, -12MAWS A5.29/A5.29ME6XT1-NiC, -NiME7XT1-XC, -XME7XT5-XC, -XME8XT1-NiXC, -NiXME8XT5-NiXC, -NiXME8XT1-W2C, -W2M

345 [50] 450 [65] 22 27 @ –20°C[20 @ 0°F]

27 @ –30°C[20 @ –20°F]

GMAWAWS A5.18/A5.18ME70C-3C. E70C-3M,E70C-6C, E70C-6MAWS A5.28/A5.28ME70C-XXXE80C-NiXE80C-W2

345 [50] 450 [65] 22 27 @ –20°C[20 @ 0°F]

27 @ –30°C[20 @ –20°F]

Table 4.1 (Continued)Matching Filler Metal Requirements for WPSs Qualified in Conformance with 5.12

Base Metal




MinimumYield

Strength,MPa [ksi]

Minimum Tensile

Strength,MPa [ksi]



I and II III

(Continued)

78


M270M [M270](A 709M [A 709])Gr. HPS 485W [HPS 70W]

SMAWAWS A5.5/A5.5ME9018M

Prequalified—Exempt from Test

SAWAWS A5.23/A5.23MF9A0-EXXX-XXF9A0-ECXXX-XXF9A2-EXXX-XXF9A2-ECXXX-XX

485 [70] 610 [90] 17 34 @ –25° C[25 @ –10° F]

34 @ –30° C[25 @ –25° F]

FCAW-GAWS A5.29/A5.29ME9XT1-XC, -XME9XT5-XC, -XM

485 [70] 610 [90] 17 34 @ –25° C[25 @ –10° F]

34 @ –30° C[25 @ –25° F]

GMAWAWS A5.28/A5.28ME90C-K3

485 [70] 610 [90] 17 34 @ –25° C[25 @ –10° F]

34 @ –30° C[25 @ –25° F]

M270M [M270](A 709M [A 709])Gr. 690, 690W [100, 100W]Over 60 mm[2-1/2 in] thick

SMAWAWS A5.5/A5.5ME10018-ME11018-M


SAWAWS A5.23/A5.23MF10A4-EXXX-XXF10A4-ECXXX-XXF11A4-EXXX-XXF11A4-ECXXX-XX

600 [90] 675 [95] 16 27 @ –40° C[20 @ –40° F]

As Approvedby Engineer

FCAW-GAWS A5.29/A5.29ME10XT1-XC, -XME10XT5-XC, -XME11XT1-XC, -XME11XT5-XC, -XM

600 [90] 675 [95] 16 27 @ –40° C[20 @ –40° F]


GMAWAWS A5.28/A5.28ME100C-K3E110C-K3, K4

600 [90] 675 [95] 16 27 @ –40° C[20 @ –40° F]



Base Metal




MinimumYield

Strength,MPa [ksi]

Minimum Tensile

Strength,MPa [ksi]



I and II III

(Continued)

79



Notes:1. When welds are to be stress-relieved, the weld metal shall not exceed 0.05% vanadium. The stress-relieved weld shall meet the minimum mechanical

properties and impact properties specified in the contract.2. Special welding materials and procedures may be required to match atmospheric, corrosion, and weathering characteristics (see Table 4.3 for

M270M [M270] (A 709M [A 709]) Gr. 345W [50W] and Gr. HPS 345W [HPS 50W] steels). Filler metal with suitable weathering characteristicsfor bare unpainted applications of M270M [M270] (A 709M [A 709]) Gr. 690, 690W [100, 100W] and M270M [M270] (A 709M [A 709]) Gr.HPS 485W [HPS 70W] steels shall be approved by the Engineer.

3. When joining HPS 485W [HPS 70W], the weld deposit shall have a minimum content of 0.8% nickel as determined by A5.XX filler metal tests.4. Electrode specifications with the same yield and tensile properties, but with lower impact test temperature, may be substituted. (e.g., F7A2-EXXX

may be substituted for F7A0-EXXX).5. For base metal thickness or electrode specification not included in this table, see Table 4.2.6. The Engineer may accept the results of test that vary from the limits established by this table based upon the following rules:

(a) The yield strength of the weld metal may be up to 70 MPa [10 ksi] less than the minimum specified yield strength of the matching weld metalwhen stress in the weld is compression normal to the effective area of the weld.

(b) Ductility and toughness shall be as specified except when otherwise approved for specific projects or applications.(c) Acceptance of modified mechanical properties by one State does not obligate other States to accept the same modifications.

7. All listed values are minimums unless a range is shown.8. The 550 MPa [80 ksi] filler metals are intended for exposed applications of weathering steels. They need not be used on applications of M270M

[M270] (A 709M [A 709]) Gr. 345W [50W] or Gr. HPS 345W [HPS 50W] that will be painted.9. The provisions of 5.13 may be used as an option to 5.12.

10. See 5.5.1 for filler metal qualification requirements.11. Filler metals for alloy groups B3, B3L, B4, B4L, B5, B5L, B6, B6L, B7, B7L, B8, B8L, or B9 in AWS A5.5/A5.5M, A5.23/A5.23M, A5.28/

A5.28M, and A5.29/A5.29M shall be prohibited in the as-welded condition.12. In joints involving base metals of two different yield strengths, filler metal applicable to the lower strength base metal may be used.13. AWS A5M (SI units) electrodes of the same classification may be used in lieu of the AWS A5 (U.S. Customary Units) electrode classification.

Table 4.2Matching Filler Metal Requirements for WPSs Qualified in Conformance with 5.13

Base Metal


Qualification Test Requirement


MinimumYield

Strength,MPa [ksi]

Minimum Tensile

Strength,MPa [ksi]

Elongation in 50 mm[2 in], %

CVN, J [ft∙lb] AASHTO Temperature Zones

I and II III

M270M [M270] (A 709M [A 709]) Gr. 250 [36]

FCAW-SAWS A5.20/A5.20ME6XT-6, 8E7XT-6, 8AWS A5.29/A5.29ME6XT8-XE7XT4-XE7XT6-XE7XT7-XE7XT8-XE8XT8-X

300 [45] 400 [65] 22 27 @ –20° C[20 @ 0° F]

27 @ –30° C[20 @ –20° F]

GMAWAWS A5.18/A5.18MER70S-2, 3, 6, 7AWS A5.28/A5.28MER80S-NiX

300 [45] 400 [65] 22 27 @ –20° C[20 @ 0° F]

27 @ –30° C[20 @ –20° F]

(Continued)

80


M270M [M270] (A 709M [A 709]) Gr. 250 [36](Cont’d)

ELECTROSLAG—Not Authorized for Tension and Reversal Members

AWS A5.25/A5.25MFES60-XXXFES62-XXXFES70-XXXFES72-XXX

300 (45) 400 [65]242222

20 @ –20° C[15 @ 0° F]


ELECTROGAS—Not Authorized for Tension and Reversal Members

AWS A5.26/A5.26MEG60X-XEG62X-XEG70X-XEG72X-X

345 [50] 400 [65]

24242222

20 @ –20° C[15 @ 0° F]


M270M [M270] (A 709M [A 709]) Gr. 345 [50] Type 1, 2, or 3, Gr. 345W [50W] Gr. HPS 345W [HPS 50W] 100 mm [4 in]and under

GMAWAWS A5.18/A5.18MER70S-2, 3, 6, 7AWS A5.28/A5.28MER80S-NiX

345 [50] 450 [65] 22 27 @ –20° C[20 @ 0° F]

27 @ –30° C[20 @ –20° F]

FCAW-SAWS A5.20/A5.20ME7XT-6, 8AWS A5.29/A5.29ME6XT8-XE7XT4-XE7XT6-XE7XT7-XE7XT8-XE8XT8-X

345 [50] 450 [65] 22 27 @ –20° C[20 @ 0° F]

27 @ –30° C[20 @ –20° F]

ELECTROSLAG—Not Authorized for Tension and Reversal Members

AWS A5.25/A5.25MFES70-XXXFES72-XXX

345 [50] 450 [65] 22 27 @ –20° C[20 @ 0° F]


ELECTROGAS—Not Authorized for Tension and Reversal Members

AWS A5.26/A5.26MEG70X-XEG72X-X

345 [50] 450 [65] 22 27 @ –20° C[20 @ 0° F]


M270M [M270] (A 709M [A 709]) Gr. HPS 485W [HPS 70W]

As Approved by Engineer (see Table 4.1)


Base Metal




MinimumYield

Strength,MPa [ksi]

Minimum Tensile

Strength,MPa [ksi]



I and II III

(Continued)

81


Notes:1. When welds are to be stress-relieved, the weld metal shall not exceed 0.05% vanadium. The stress-relieved weld shall meet the minimum mechan-

ical properties and impact properties specified in the contract.2. Special welding materials and procedures may be required to match atmospheric, corrosion, and weathering characteristics (see Table 4.3 for

M270M [M270] (A 709M [A 709]) Gr. 345W [50W] and Gr. HPS 345W [HPS 50W] steels). Filler metal with suitable weathering characteristicsfor bare unpainted applications of M270M [M270] (A 709M [A 709]) Gr. 690, 690W [100, 100W] and M270M [M270] (A 709M [A 709]) Gr.HPS 485W [HPS 70W] steels shall be approved by the Engineer.

3. When joining HPS 485W [HPS 70W], the weld deposit shall have a minimum content of 0.8% nickel as determined by A5.XX filler metal tests.4. Electrode specifications with the same yield and tensile properties, but with lower impact test temperature, may be substituted. (e.g., F7A2-EXXX

may be substituted for F7A0-EXXX).5. The Engineer may accept the results of tests that vary from the limits established by this table based upon the following rules:

(a) The yield strength of the weld metal may be up to 70 MPa [10 ksi] less than the minimum specified yield strength of the matching weld metalwhen stress in the weld is compression normal to the effective area of the weld.

(b) Ductility and toughness shall be as specified except when otherwise approved for specific projects or applications.(c) Acceptance of modified mechanical properties by one State does not obligate other States to accept the same modifications.

6. All listed values are minimums unless a range is shown.7. The 550 MPa [80 ksi] filler metals are intended for exposed applications of weathering steels. They need not be used on applications of M270M

[M270] (A 709M [A 709]) Gr. 345W [50W] or Gr. HPS 345W [HPS 50W] that will be painted.8. See 5.5.1 for filler metal qualification requirements.9. Filler metals for alloy groups B3, B3L, B4, B4L, B5, B5L, B6, B6L, B7, B7L, B8, B8L, or B9 in AWS A5.5/A5.5M, A5.23/A5.23M, A5.28/

A5.28M, and A5.29/A5.29M shall be prohibited in the as-welded condition.10. In joints involving base metals of two different yield strengths, filler metal applicable to the lower strength base metal may be used.11. AWS A5M (SI units) electrodes of the same classification may be used in lieu of the AWS A5 (U.S. Customary Units) electrode classification.

M270M [M270] (A 709M [A 709]) Gr. 690, 690W [100, 100W]Over 60 mm[2-1/2 in] thick

GMAWAWS A5.28/A5.28MER 100S-1ER 100S-2 600 [90] 675 [95] 16 27 @ –40° C

[20 @ –40° F]As Approvedby Engineer

M270M [M270](A 709M [A 709]) Gr. 690, 690W [100, 100W] 60 mm [2-1/2 in] thick or less

SMAWAWS A5.5/A5.5ME11018M

670 [95] 745 [110] 20 27 @ –40° C[20 @ –40° F]


SAWAWS A5.23/A5.23MF11A4-EXXX-XXF11A4-ECXXX-XX

670 [95] 745 [110] — 27 @ –40° C[20 @ –40° F]


FCAW-GAWS A5.29/A5.29ME11XT1-XC, -XME11XT5-XC, -XM

670 [95] 745 [110] 20 27 @ –40° C[20 @ –40° F]


GMAWAWS A5.28/A5.28M ER110S-1E110C-K3, -K4

670 [95] 745 [110] 20 27 @ –40° C[20 @ –40° F]



Base Metal




MinimumYield

Strength,MPa [ksi]

Minimum Tensile

Strength,MPa [ksi]



I and II III

82


Table 4.3Filler Metal Requirements for Exposed Bare Application

of M270M [M270] (A 709M [A 709]) Gr. 345W [50W] and Gr. HPS 345W [HPS 50W] Steels

Process Filler Metal Specification Approved Electrodes

SMAW A5.5/A5.5M00All electrodes that deposit weld metal meeting a C1, C1L, C2, C2L, C3, W1, or W2 analysis.

SAW A5.23/A5.23MAll electrode-flux combinations that deposit weld metal with a Ni1, Ni2, Ni3, Ni4, or W analysis.

FCAW A5.29/A5.29MAll electrodes that deposit weld metal with a Ni1, Ni2, Ni3, Ni4, or W analysis.

GMAW A5.28/A5.28MAll electrodes that meet filler metal composition requirements of Ni1, Ni2, Ni3, or W2 analysis.

Notes:1. Filler metals meeting the requirements of this table shall also meet all requirements of Table 4.1 or 4.2 before being approved for bridge welding.

These requirements include yield strength, tensile strength, elongation and CVN test properties.2. The values listed are minimums unless a range is shown.3. This is a partial listing which does not cover EGW or ESW of M270M [M270] (A 709M [A 709]) Gr. 345W [50W] or Gr. HPS 345W [HPS 50W]

steel and makes no provision for other steels with weathering characteristics such as M270M [M270] (A 709M [A 709]) Gr. HPS 485W [HPS70W] or M270M [M270] (A 709M [A 709]) Gr. 690, 690W [100, 100W] steels.The Engineer shall approve all filler metal to be used in exposed, unpainted applications not covered by this table. The chemical composition ofweld metal deposited by the electrodes listed in this table may be used as a guide to weld metal chemistry considered acceptable in weathering ap-plications. There is considerable dilution of base metal in ESW and EGW; therefore, the weld deposit will not match the electrode or base metalchemistry.

4. See 5.5.1 for filler metal qualification requirements.5. AWS A5M (SI Units) electrodes of the same classification may be used in lieu of the AWS A5 (U.S. Customary Units) electrode classification.

Table 4.4Minimum Preheat and Interpass Temperature, °C [°F]

Welding Process (Base Metal)To 20 mm

[3/4 in] Incl.

Thickness of Thickest Part atPoint of Welding, mm [in]

Over 65 mm[2-1/2 in]

Over 20 mm[3/4 in]

to 40 mm[1-1/2 in] Incl.

Over 40 mm[1-1/2 in]to 65 mm

[2-1/2 in] Incl.

SAW; GMAW; FCAW; SMAW (M270M [M270][A 709M (A 709)] Gr. 250 [36], 345 [50], 345W[50W], HPS 345W [HPS 50W])

10 [50] 20 [70] 65 [150] 110 [225]

SAW; GMAW; FCAW; SMAW (M270M [M270][A 709M (A 709)] Gr. HPS 485W [HPS 70W],690 [100], 690W [100W])a

10 [50] 50 [125] 80 [175] 110 [225]

a See 4.2.2 for maximum preheat and interpass temperature limitations.

Note: See Annex G and Tables 12.3, 12.4, and 12.5 for alternate preheat and interpass temperatures.

83


Table 4.5Minimum Holding Time (see 4.4.2)

6 mm [1/4 in] or LessOver 6 mm [1/4 in]

Through 50 mm [2 in] Over 50 mm [2 in]

15 minutes 4 minutes/2 mm [1/16 in]2 hrs plus 15 minutes for each additional

25 mm over 50 mm [1 in over 2 in]

Table 4.6Alternate Stress-Relief Heat Treatment (see 4.4.3)

Decrease in Temperature BelowMinimum Specified Temperature, ∆ °C [°F]

Minimum Holding Time at DecreasedTemperature, Hours per 25 mm [1 in] of Thickness

30 [50]060 [100]90 [150]

120 [200]

235

100

Table 4.7Allowable Atmospheric Exposure of Low-Hydrogen SMAW Electrodes

Electrode Hours

A5.1E70XX 4 max.

A5.5E70XX-XE80XX-XE90XX-XE100XX-XE110XX-X

/04 max./02 max./01 max.1/2 max.1/2 max.

84


Figure 4.1—Weld Bead in Which Depth and WidthExceed the Width of the Weld Face (see 4.7.7)


85

5.0 ScopeQualification of a Welding Procedure Specification(WPS) is covered in Part A. Qualification of weldingpersonnel (i.e., welders, welding operators, and tackwelders) is covered by Part B.

Part AWelding Procedure Specification

(WPS) Qualification

5.1 ApprovalApproval of WPSs shall be based upon the results ofmechanical tests that demonstrate that the process andWPS used will produce sound weld metal with requiredstrength, ductility, and toughness.

The mechanical properties of fillet and groove weldsshall be determined using standard groove weld tests.The soundness of fillet and groove test welds shall bedetermined by RT, mechanical tests, and etching of testwelds. The soundness of production welds shall be estab-lished by visual tests and NDT as required by this code.

5.1.1 Purpose of WPS Qualification Tests. The WPSqualification tests required by this code are designed toprovide assurance that the weld metal produced by weld-ing in conformance with the provisions of this code shallproduce weld metal strength, ductility, and toughnessconforming to the provisions of Tables 4.1 and 4.2, asappropriate.

5.2 Qualification ResponsibilityEach Contractor shall conduct tests to qualify or verifyWPSs as required by this code (see 5.13 for WPS qualifi-cation requirements).

5.2.1 Acceptance Requirements. Acceptance of WPSqualification tests shall be as described in 5.2.3 and 5.3.

5.2.2 Contractor. The Contractor shall prepare WPSs,based upon the heat input and electrical controls imposedby the PQR, and, within these limits, shall specify weld-ing variables that will produce the welding conditions,characteristics, weld sizes, and contours required in thework.

5.2.3 Engineer. The Engineer should accept properlydocumented evidence of previous qualification of weld-ers, welding operators, and tack welders. The Engineershall accept evidence of previous WPS, pretest or verifi-cation qualification testing, provided (1) the PQR shallbe complete and shows compliance with the mechanicaltest requirements of these specifications, and (2) theresults of the tests shall be certified as accurate by a staterepresentative or an independent third party acceptable tothe state.

5.2.4 Excess Testing. Testing in excess of that requiredby this code shall be paid for by the Owner at pricesestablished by agreement with the Contractor unless oth-erwise provided in the contract documents. Irrespectiveof this requirement, the Engineer may order tests ofwelders, welding operators, or WPSs whenever there isevidence that unacceptable welds are being or have beenproduced.

5.2.5 Records. Records of the test results shall be keptby the Contractor/fabricator/erector and shall be madeavailable to those authorized to examine them.

5.3 Duration

All WPSs, except as provided in 1.3.6, 5.11, and 12.7,shall be based upon tests which have been performed notmore than 60 months in advance of production welding.This requirement applies to WPS qualification tests, pre-tests, and verification tests.

5. Qualification

CLAUSE 5. QUALIFICATION AASHTO/AWS D1.5M/D1.5:2008

86

5.4 Base MetalThe following provisions cover the base metal to be usedfor WPS qualification, pretest, and verification tests.

5.4.1 Base-Metal Qualification Requirements. Theproduction base metals qualified by the PQR base metalshall conform to the following:

5.4.2 M270M [M270] Grade 345W Test Plate Chem-istry Requirements. When M270M [M270] Grade345W [50W] (A 709M [A 709] Grade 345W [50W]) testplate and backing steel is used to qualify all AASHTOsteels having a specified minimum yield strength of 345MPa [50 ksi], or less, the M270M [M270] Grade 345W[50W] (A 709M [A 709] Grade 345W [50W]) steel shallhave the following chemical composition:

Element Composition, min, %

Carbon 0.15Manganese 1.00Silicon 0.25Chromium 0.50Vanadium 0.03

Test plate and backing steel that does not have a chemi-cal composition that conforms to the above limits may beused, provided the steel has equivalent hardenabilitydetermined by one of the following:

PQR Test PlateSpecification and Grade(See Note)

Qualified ProductionBase Metal Specification and Grade

M270M [M270](A 709M [A 709])Gr. 250 [Gr. 36]

M270M [M270] (A 709M [A 709]) Gr. 250 [Gr. 36]

M270M [M270](A 709M [A 709])Gr. 345 [Gr. 50]

M270M [M270] (A 709M [A 709]) Gr. 250, 345 [Gr. 36, 50]

M270M [M270](A 709M [A 709])Gr. 345W [Gr. 50W](meeting requirements of 5.4.2)

M270M [M270] (A 709M [A 709]) Gr. 250, 345, 345W, HPS 345W [Gr. 36, 50, 50W, HPS 50W]

M270M [M270](A709M [A 709])Gr. HPS 345W [Gr. HPS 50W]

M270M [M270] (A 709M [A 709]) HPS 345W [Gr. HPS 50W]

Any steel with minimum specified yield strength >345 MPa [50 ksi]

PQR Test Plate Specification and Grade

Note: All test plate material should have a minimum CVN test value of27 J [20 ft∙lb] at 4°C [40°F].

(1) The Carbon Equivalent shall be 0.45% minimumas determined by the formula

CE = C +

Carbon shall be 0.12% minimum.

or

(2) The hardenability shall be equivalent to steelmeeting the requirements of 5.4.2(1) when computedbased upon an ideal critical diameter, whether calculatedor experimental.

5.4.3 Use of Unlisted Base Metals. When a steel otherthan one of those described in 1.2.2 is approved under theprovisions of the general specification, and such steel isproposed for welded construction under this code, WPSsshall be established by qualification in conformance withthe requirements of 5.13. The fabricator shall have theresponsibility for establishing the WPS by qualification.

5.4.3.1 The Engineer shall require evidence of ade-quate weldability of the steel, which as a minimum shallrequire the following:

(1) Acceptance by other national codes such asASME, AWS (Offshore Applications), and ABS (Ships)of the steel for similar or stricter requirements forstrength and toughness at equivalent loading rates.

(2) A minimum history of five-year use under similarconditions of loading.

(3) Records of past weld testing that would verifyadequate resistance of the steel to hydrogen cracking atmedium restraint levels. These tests should also establishthe maximum and minimum heat input range for eachwelding process to be used in construction.

5.4.3.2 The responsibility for determining weldabil-ity, including the assumption of additional testing costsinvolved, shall be assigned to the party who either speci-fies a material not described in 1.2.2 or who proposes theuse of a substitute material not described in 1.2.2. Theparty proposing the use of a substitute material notdescribed in 1.2.2 shall assume the additional costsinvolved in establishing the WPS as required in 5.4.3.

5.4.3.3 When base metals not described in 1.2.2 areapproved for welding to base metals of the same specifi-cation and grade or to steels described in 1.2.2, the weld-ing procedure shall be qualified by test under theprovisions of 5.13.

(1) In addition, when specified in the contract docu-ments or ordered by the Engineer, CVN tests shall bemade to measure the toughness of the coarse-grainedarea of the HAZ (see 5.4.3.5).

(Mn + Si)6

----------------------- (Cr + Mo + V)5

----------------------------------- (Ni + Cu)15

-----------------------+ +

PART A

AASHTO/AWS D1.5M/D1.5:2008 CLAUSE 5. QUALIFICATION

87

(2) The WPS shall list all welding variables and theminimum preheat and interpass temperature for thethicknesses listed in Table 4.4.

(a) When quenched and tempered steels are to bewelded, both the minimum and maximum preheat andinterpass temperatures shall be listed for each weldingheat input and thickness as shown in Table 12.5.

(b) The WPS shall list any special precautionsnecessary to avoid weld and HAZ cracking and to ensurethat the required strength, ductility, and toughness willbe produced.

5.4.3.4 Unlisted Steels with Fy ≥ 485 MPa [70 ksi].WPSs used to produce matching weld metal to joinsteels, with a minimum specified yield strength of 485MPa [70 ksi] or greater that are not described in 1.2.2,shall be qualified by the Contractor as specified in thecontract documents or ordered by the Engineer in con-formance with 5.4.3. Weldability testing shall be asdetermined by the Engineer, or approved by AASHTO.

5.4.3.5 Charpy V-Notch (CVN) Test Require-ments. WPS qualification tests for welds on steels withminimum specified yield strength of 485 MPa [70 ksi] orgreater shall measure strength, ductility, toughness, andsoundness of the weld metal. When specified in the con-tract documents, qualification tests for steels shall alsomeasure the CVN test values of the coarse grained areaof the HAZ. The minimum CVN test energy, test temper-ature, orientation of the notch, and other necessarydetails shall be specified in the contract documents whenHAZ testing is required.

5.4.4 CMTRs. Copies of certified mill test reports(CMTRs) shall be furnished for all plates and backingused in testing.

5.4.5 WPS Backing. Steel backing used in weld testsshall be of the same specification and grade as the weldtest plates, but CVN tests shall not be required.

5.4.6 Base Metal for Undermatched Welds. WPSs forwelds that undermatch the base metal strength shall bebased on PQRs that utilize undermatching filler metaland the higher strength of steel to be used in production.

5.5 Welding ConsumablesWelding consumables shall conform to the provisions ofthe appropriate filler metal specifications described inTables 4.1, 4.2, or other specification approved by theEngineer. Filler metal tests of conformance shall be con-ducted by the manufacturers of welding consumables, asrequired by the specifications. The tests shall conform tothe requirements for the electrode, electrode-flux combi-

nation, or electrode-shielding gas(es), as specified tomatch the base metal to be welded, unless otherwisespecified in the contract documents. Tests shall be con-ducted annually unless otherwise specified, and certifica-tion shall be as specified in Clause 4.

5.5.1 WPS Requirements for Consumables. See Table 5.1for the WPS qualification requirements for consumables.

5.5.2 Active Flux. WPSs that use active fluxes shall belimited to single- and two-pass applications, unless theWPS is qualified under the provisions of 5.13 andapproved by the Engineer.

5.5.3 Undermatching Filler Metal. When specified inshop drawings, undermatching filler metal shall be used.Qualifications of WPSs using undermatching filler metalshall conform to 5.7.11.

5.6 Test Plate Thickness5.6.1 WPSs for SMAW, FCAW, GMAW, and SAWshall be based on PQR test plates with thicknessesgreater than or equal to 25 mm [1 in], and shall qualifythe WPS for use on all steel thicknesses covered by thiscode.

5.6.2 EGW and ESW WPSs. Test plates shall conformto Table 5.4(17).

5.6.3 Fillet Weld Soundness Tests. Fillet weld sound-ness test plate thickness shall conform to Figure 5.8.

5.7 General Requirements for WPS Qualification

5.7.1 WPS Qualification Test. A WPS qualification testis a test performed by the Contractor in conformancewith 5.12 or 5.13. Figure 5.1 shall be used for all WPSqualification testing. Prequalified WPSs in conformancewith 5.11, or qualified WPSs in conformance with 5.12or 5.13, may be used with joint details described in Fig-ures 2.4 or 2.5 without further testing.

5.7.2 Pretest. A WPS pretest is a WPS qualification testperformed in conformance with 5.12 by someone otherthan the Contractor, but used by the Contractor as a basisfor preparing WPSs. Figure 5.1 shall be used for all pre-testing qualification.

5.7.3 Verification of Pretest PQRs. A WPS verificationtest is a simplified version of a WPS qualification testthat shall be performed by the Contractor when verifyinga Procedure Qualification Record (PQR) which wasobtained from a third party that had performed a pretest.Qualification tests performed under 5.12 or 5.13 shall not

PART A


88

require verification testing. Figure 5.2 shall be used forall verification testing.

5.7.4 Table 4.1 Processes. WPSs using SAW andFCAW-G, with electrode-flux and electrode-shieldinggas combinations listed in Table 4.1 shall be approved,based upon qualification testing or pretesting and verifi-cation testing, as provided in 5.12 or 5.13.

5.7.4.1 Consumables. WPSs employing consumableslisted in Table 4.1 may be pretested or qualified for aspecific project or application at the option of the Con-tractor. Pretesting, as described in 5.7.2, may be per-formed by manufacturers of welding consumables,Contractors, or independent agencies. Qualification test-ing under 5.12 or 5.13 may be performed only by theContractor doing the production welding.

5.7.5 Table 4.2 Processes. WPSs using SAW, FCAW-G, FCAW-S, GMAW, EGW, ESW, and processes withelectrode-flux and electrode-shielding gas combinationslisted in Table 4.2 shall be approved based upon qualifi-cation testing in conformance with 5.13.

5.7.6 Exemption from Further Testing. WPSs forgroove and fillet welds that have been qualified by test,or pretested and verified as described in this section,which conform to the requirements of Clauses 2, 3, and4, shall be exempt from further qualification testing,unless otherwise specified in the contract documents.

5.7.7 Joints Not Conforming to Figures 2.4 or 2.5.When the Contractor elects to use groove weld detailsthat do not conform to the details of Figure 2.4 or 2.5, theWPSs using these details may be qualified by test asdescribed in 5.13 using Figure 5.3. Bend and tensile testsshall be used to evaluate soundness. The mechanicalproperties of the weld metal shall be determined by theWPS testing described in 5.12 or 5.13, using Figure 5.1.

5.7.8 Aging. No test plate or specimen produced by thetesting described in 5.12 or 5.13 shall be heat treated,stress relieved, aged at temperatures above room temper-ature, or modified in any way after welding except byapproved machining and testing procedures, unless thetreatment is stated as a requirement of the WPS and is arequirement for similar welds in the structure.

5.7.9 Combination of WPSs. A combination of prequal-ified SMAW and qualified or pretested and verifiedWPSs may be used to complete one welded joint withoutadditional testing, provided the limitations of essentialvariables and limitations of maximum heat input applica-ble to each WPS are observed.

5.7.10 Previous Code Editions. WPSs qualified to pre-vious editions of this code while those editions were ineffect shall be acceptable. The use of earlier editions in

lieu of the current edition shall be prohibited for newqualifications, unless the specific earlier edition is speci-fied in the contract documents.

5.7.11 Production WPSs that utilize undermatching fillermetal shall be qualified in conformance with 5.12 or5.13.

5.7.12 Weld Cleaning. Power tools may be used toremove discontinuities identified during the in-processwelding of WPS qualification tests. In addition, uponweld test completion, the weld may be made flush bypower tools as necessary in order to facilitate testing.

5.8 Position of Test Welds5.8.1 Qualification Requirements. All welds that willbe encountered in actual construction shall be classifiedas (1) flat, (2) horizontal, (3) vertical, or (4) overhead inconformance with the definitions of welding positionsdescribed in Figures 5.4 and 5.5. Each WPS shall betested in the position in which welding will be performedin the work.

5.8.2 Groove Weld Test Positions. Plates shall bewelded in the following positions, except that test weldsmade in the flat position shall also qualify for the hori-zontal position:

5.8.2.1 Position 1G (Flat). The test plates shall beplaced in an approximately horizontal plane and the weldmetal shall be deposited from the upper side (see Figure5.6 [Detail A]).

5.8.2.2 Position 2G (Horizontal). The test platesshall be placed in an approximately vertical plane withthe groove approximately horizontal (see Figure 5.6[Detail B]).

5.8.2.3 Position 3G (Vertical). The test plates shall beplaced in an approximately vertical plane with the grooveapproximately vertical (see Figure 5.6 [Detail C]).

5.8.2.4 Position 4G (Overhead). The test plates shallbe placed in an approximately horizontal plane and theweld metal deposited from the underside (see Figure 5.6[Detail D]).

5.8.3 Fillet Weld Test Positions. When making filletweld macroetch soundness tests for WPS qualification,test plates shall be welded in the following positions:

5.8.3.1 Position 1F (Flat). The test plates shall be soplaced that each fillet weld shall be deposited from theupper side with its axis approximately horizontal and itsthroat approximately vertical (see Figure 5.7 [Detail A]).

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5.8.3.2 Position 2F (Horizontal). The test plates shallbe so placed that each fillet weld shall be deposited onthe upper side of the horizontal surface and against thevertical surface (see Figure 5.7 [Detail B]).

5.8.3.3 Position 3F (Vertical). The test plates shall beplaced in approximately vertical planes, and each filletweld shall be deposited on the vertical surfaces (see Fig-ure 5.7 [Detail C]).

5.8.3.4 Position 4F (Overhead). The test plates shallbe so placed that each fillet weld shall be deposited onthe underside of the horizontal surface and against thevertical surface (see Figure 5.7 [Detail D)].

5.9 Options for WPS Qualification or Prequalification

Table 5.2 lists options available for prequalification orqualification of a WPS.

5.9.1 PJP Groove Welds. WPSs qualified for use as CJPgroove welds may be used to make PJP groove weldswithout additional testing. The Engineer may require theContractor to provide three macroetch test specimens toevaluate weld soundness and to verify that the requiredweld size is produced.

5.10 Fillet Weld WPS Qualification5.10.1 Groove Weld PQRs. Fillet WPSs may be writtenbased upon appropriate groove welding PQRs.

5.10.2 Fillet Weld Properties

5.10.2.1 Fillet Weld Mechanical Properties. Themechanical properties of fillet welds shall be determinedby mechanical testing of groove welds in accordancewith 5.12 or 5.13. A separate fillet weld test to verifymechanical properties shall not be required unless speci-fied in the contract documents.

5.10.2.2 Fillet Weld Soundness Test. All fillet WPSsshall be subject to fillet weld soundness macroetch quali-fication as shown in Figure 5.8. The test shall be con-ducted using WPS polarity, mean current and meanvoltage.

(1) A fillet weld macroetch test shall be made foreach WPS and position to be used in construction. Onetest weld shall be the maximum size single-pass filletweld and one test weld shall be the minimum size multi-ple-pass fillet weld used in construction. The two fillet

weld tests may be combined in a single test weldment orassembly.

(2) The weldment shall be cut perpendicular to thedirection of welding at three locations as shown in Figure5.8. Specimens representing one face of each of the threecuts shall be polished and etched to constitute a macro-etch test specimen and shall be tested in conformancewith 5.19.3.

5.11 Prequalified WPSSMAW WPSs using electrodes listed in Table 4.1 andthat conform to the requirements of this code shall beconsidered prequalified and exempt from WPS testing.

5.11.1 Prequalified Tack Weld WPS. WPSs for tackwelds which are completely remelted by subsequentSAW shall be exempt from WPS qualification testing asotherwise required by this code.

5.12 Heat Input WPSThis covers WPS qualification or pretesting and verifica-tion using filler metal meeting the requirements of Table4.1, and the details of Figures 2.4 and 2.5. Either 5.12.1or 5.12.2 may be selected for WPS qualification (see5.12.3.1 and 5.12.3.3 to determine production heat inputlimitations).

Heat input shall be determined using the formula:

5.12.1 Maximum Heat Input. To qualify GMAW(metal cored), SAW, or FCAW-G WPSs for filler metalslisted in Table 4.1, tests shall be conducted using Figure5.1, with a WPS that produces the highest calculatedwelding heat input and, therefore, the slowest coolingrate of the weld and base metal HAZ. Tests to verify aWPS shall use Figure 5.1 or 5.2.

The following are WPS parameters:

5.12.1.1 Electrodes. The number of electrodes shallbe as described in the WPS. (Size of the electrode shallnot be an essential variable in this method.)

5.12.1.2 Electrical Parameters. Current type, polar-ity, and specified electrical electrode extension (electrical

Heat Input(kilojoules/mm)

Amperage Voltage 0.06××Travel Speed (mm/minute)-------------------------------------------------------------------=

Heat Input(kilojoules/in)

Amperage Voltage 0.06××Travel Speed (in/minute)

-------------------------------------------------------------------=

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stickout) shall be as described in the WPS. A change inelectrode extension of 20 mm [3/4 in] or more for SAW,or 6 mm [1/4 in] or more for FCAW-G or GMAW (metalcored), shall require requalification.

5.12.1.3 Maximum Current. Current shall be WPSmaximum.

5.12.1.4 Maximum Voltage. Voltage shall be WPSmaximum.

5.12.1.5 Minimum Gas Flow. Shielding gas flowrate shall be WPS minimum.

5.12.1.6 Minimum Preheat and Interpass Temper-ature. The minimum preheat and interpass temperatureshall be 100°C [210°F].

5.12.1.7 Maximum Interpass Temperature. Themaximum interpass temperature shall be as specified onthe WPS.

5.12.2 Maximum-Minimum Heat Input. Testing toestablish the maximum-minimum heat input envelopefor approval of SAW, FCAW-G, or GMAW (metalcored) WPSs for filler metals listed in Table 4.1 shall bedone using Figure 5.1 for qualification, and Figures 5.1or 5.2 for verification. A group of WPSs that use thesame basic welding process, i.e., same electrode type,manufacturer, or classification, same current type andpolarity, same electrode-flux/shielding-gas combination,same electrode extension, but possibly different elec-trode diameters and operating variables, may be quali-fied using the WPS, modified to produce both themaximum and minimum heat input as follows:

5.12.2.1 Maximum Heat Input. Conduct the maxi-mum heat input test as described in 5.12.1.

5.12.2.2 Minimum Heat Input. Conduct the mini-mum heat input test. Welding variables shall be selectedto produce the lowest heat input and therefore, the fastestcooling rates in the weld and HAZ as follows:

(1) Number of electrodes shall be as described in theWPS. (Size of electrodes is not an essential variable inthis method.)

(2) Current type, polarity, and specified electricalelectrode extension shall be as described in the WPS. Achange in electrode extension of 20 mm [3/4 in] or morefor SAW, or 6 mm [1/4 in] or more for FCAW-G orGMAW (metal cored), shall require requalification.

(3) Current shall be WPS minimum.

(4) Voltage shall be WPS minimum.

(5) Shielding gas shall be WPS maximum.

(6) The minimum preheat temperature shall be 10°C[50°F]. The maximum preheat temperature shall be 40°C[100°F].

(7) The maximum interpass temperature shall notexceed 50°C [125°F]. The test plate may be cooled artifi-cially between passes (see 5.12.1).

5.12.3 Production Welding Limitations

5.12.3.1 Maximum Heat Input Envelope. SAW,FCAW-G, or GMAW (metal cored) WPSs, qualified orpretested and verified in conformance with the provi-sions of 5.12.1, shall be operated between 60% and100% of the qualified maximum PQR heat input.

5.12.3.2 Maximum Heat Input PQR Current, Volt-age, and Travel Speed. When WPS qualification isbased upon maximum heat input testing under the provi-sions of 5.12.1, current and voltage shall not exceed themaximum values recorded in the Procedure QualificationRecord (PQR). After current and voltage have beenselected, the travel speed shall be adjusted so that theheat input conforms to the requirements of 5.12.3.1. Cur-rent and voltage shall not be reduced by more than 20%and 14%, respectively, from the maximum valuesrecorded in the PQR.

5.12.3.3 Maximum-Minimum Heat Input Enve-lope. SAW, FCAW-G, or GMAW (metal cored) WPSsqualified or pretested and verified in conformance with5.12.2, shall be operated at any calculated welding heatinput between the qualified maximum and minimumPQR heat input.

5.12.3.4 Maximum-Minimum Heat Input Cur-rent, Voltage, and Travel Speed. When WPS qualifica-tion is based upon maximum-minimum heat input testingunder 5.12.2, the current and voltage shall not be morethan the maximums or less than the minimums recordedin the PQR. Travel speed shall be adjusted so that theheat input conforms to 5.12.3.3.

5.13 Production Procedure WPSThe provisions of this subclause shall apply to WPSswith filler metals in Table 4.1 or 4.2, and standard ornonstandard joints.

5.13.1 Filler Metals Not Described in Table 4.1. WPSsqualified with filler metals not described in Table 4.1,and if the WPS is not qualified (as described in 5.12), theWPS shall be qualified observing the limitation of vari-ables described in Table 5.3.

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5.13.2 Nonprequalified SMAW WPS. SMAW WPSsusing electrodes described in Table 4.2 shall be subjectto WPS qualification testing as described in 5.13.

5.13.3 Limitations. When a WPS is qualified under theprovisions of 5.13, the Contractor shall conduct therequired tests and record the specific values for essentialvariables listed in Table 5.3. Preheat and interpass tem-peratures for the testing shall be as required by 4.2. Arecommended form listing the information required inthe WPS is given in Annex L.

Changes to the PQR variables in Table 5.3 shall requireWPS requalification. When a combination of WPSs isused, the variables applicable to each WPS shall apply.

5.14 ESW and EGWESW and EGW WPSs shall be qualified as described in5.13, using Figure 5.1, modified as described in 5.14.1.

5.14.1 Figure 5.1. Test plates used to qualify ESW, orEGW WPS shall conform to Figure 5.1. Test plates shallhave sufficient length of weld to allow the machiningand testing of eight CVN test specimens, except theplates shall have a square butt preparation without steelbacking, unless otherwise required by the WPS.

5.14.2 Limitations. Supplementing the variables ofTable 5.3, the additional essential variables of Table 5.4apply to ESW or EGW WPSs. Changes beyond theseadditional variable limits shall also require WPSrequalification.

5.15 Type of Tests and PurposeMechanical testing shall verify that the WPS producesthe strength, ductility, and toughness required by Tables4.1, 4.2, or as approved by the Engineer for the fillermetal tested. Soundness tests shall meet the requirementsof 5.19.2 and 5.19.3. The tests described below are usedto determine the mechanical properties and the sound-ness of welds deposited following a given WPS. Thetests are as follows:

5.15.1 Groove Welds. The following shall be tests forgroove welds made with matching or undermatchingfiller metal.

(1) All weld-metal tension tests to measure tensilestrength, yield strength, and ductility.

(2) CVN test, to measure relative fracture toughness.

(3) Macroetch tests, to evaluate soundness, and tomeasure effective throat or weld size; also, used to gagethe size and distribution of weld layers and passes.

(4) RT test to evaluate weld soundness.

In addition, the following tests shall be required formatching weld strength groove welds. They shall not berequired for undermatching weld strength applications:

(5) Reduced section tensile test, to measure tensilestrength.

(6) Side-bend test, to evaluate soundness andductility.

5.15.2 Fillet Welds. Tests for fillet welds shall be thefollowing:

5.15.2.1 Mechanical Properties. The mechanicalproperties of fillet welds shall be measured by testinggroove welds unless otherwise specified in the contractdocuments.

5.15.2.2 Macroetch. The fillet weld soundness mac-roetch test shall be used to evaluate weld soundness andto gage the size, shape, and distribution of individualweld passes.

5.16 Weld Specimens—Number, Type, and Preparation

5.16.1 Configuration. The type and number of the spec-imens that shall be tested to qualify a WPS are shown inFigure 5.1.

5.16.2 Corner and T-Joints. Test plates for groovewelds in corner or T-joints shall be butt joints having thesame groove configuration as the corner or T-joint to beused in construction, except the depth of groove need notexceed 25 mm [1 in].

5.16.3 Mechanical Testing. Test specimens shall beremoved from the test plate by thermal cutting ormachining. Specimens removed by thermal cutting shallhave sufficient material in the initial test blank to allowall thermal cutting HAZ material to be removed by sub-sequent machining. Care shall be taken not to overheatsmall specimens.

Each test shall include specimens described in Table 5.5.

Mechanical test specimens, except CVN test specimens,shall be prepared as follows:

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(1) All-weld-metal tension test specimens, preparedfor testing in conformance with Figure 5.9

(2) Reduced section tension test specimens, preparedfor testing in conformance with Figure 5.10.

(3) Side bend specimens, prepared for testing in con-formance with Figure 5.11.

(4) Root and face bend specimens prepared for test-ing in conformance with Figure 5.12. (Used only for spe-cial applications of welder qualification.)

5.16.4 CVN Tests. The CVN test specimens shall beprepared for testing in conformance with Figure 5.13 asfollows:

(1) Five specimens shall be machined from each testweld made by SMAW, SAW, FCAW, or GMAW andtested at the specified temperature.

(2) Eight specimens shall be machined from each testweld made by ESW or EGW and tested at the specifiedtemperature.

5.17 Nondestructive Testing (NDT)Before preparing mechanical test specimens, the qualifi-cation test plate shall be radiographed in conformancewith the provisions of Clause 6. Weld quality shall meetthe requirements of 6.26.1 and 6.26.2, except that for theWPS test for M270M [M270] (A 709M [A 709]) Grades690 [100] and 690W [100W] steels, there shall be no dis-continuities other than allowable porosity in the test weld.Portions of weld test plates marked “discard” are not subjectto inspection or test.

5.18 Method of Testing Specimens5.18.1 Reduced Section Tension Specimens. Beforetesting, the least width and corresponding thickness ofthe reduced section shall be measured in millimeters[inches]. The specimen shall be ruptured under tensileload, and the maximum load in newtons (kips) shall bedetermined. The cross-sectional area shall be obtained bymultiplying the width by the thickness. The tensilestrength shall be obtained by dividing the maximum loadby the area of the cross section.

For plate thickness greater than 26 mm [1 in], full thick-ness specimens or multiple specimens may be used.When multiple specimens are used in lieu of full thick-ness specimens, each set shall represent a single tension

test of the full plate thickness. When multiple specimensare used, the entire thickness shall be mechanically cutinto a minimum number of approximately equal strips ofa size that can be tested in available equipment. Eachspecimen shall meet the requirements of 5.19.1.

5.18.2 Macroetch Test. Macroetch soundness tests arerequired for WPS qualification testing done on test platesdescribed in Figure 5.3 and Figure 5.8. The weld testspecimens shall be prepared with a finish suitable formacroetch examination. A suitable solution shall be usedfor etching to give a clear definition of the welds show-ing the fusion line (weld-metal/base-metal interface),individual weld passes, and the HAZ.

5.18.3 Root, Face, and Side Bend Specimens. Eachspecimen shall be bent in a bend test jig that meets therequirements shown in Figure 5.14, 5.15, or 5.16 or issubstantially in conformance with these figures, and themaximum bend radius is not exceeded. Any convenientmeans may be used to move the plunger member withrelation to the die member.

5.18.3.1 Specimen Placement. The specimen shall beplaced on the die member of the jig with the weld at mid-span. Face bend specimens shall be placed with the faceof the weld directed toward the gap. Root bend and filletweld soundness specimens shall be placed with the rootof the weld directed toward the gap. Side bend speci-mens shall be placed with that side showing the greaterdiscontinuity, if any, directed toward the gap.

5.18.3.2 Weld and HAZ Placement. The plungershall force the specimen into the die until the specimenbecomes U-shaped. The weld and HAZ shall be centeredand completely within the bent portion of the specimenafter testing.

5.18.3.3 Wraparound Jig. When using the wrap-around jig, the specimen shall be firmly clamped on oneend so that there is no sliding of the specimen during thebending operation. The weld and HAZ shall be com-pletely in the bent portion of the specimen after testing.Test specimens shall be removed from the jig when theouter roll has been moved 180° from the starting point.

5.18.4 All-Weld-Metal Tension Test. The test specimenshall be tested in conformance with ASTM A 370,Mechanical Testing of Steel Products or the latest editionof AWS B4.0/B4.0M, Standard Methods for MechanicalTesting of Welds.

5.18.5 CVN Test. Toughness testing shall be performedas described for CVN test specimens under the heading“Charpy Impact Testing” of ASTM A 370 (AASHTOT 244). Only full size (10 mm × 10 mm) specimens shallbe used (see Figure 5.13).

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5.19 Test Results RequiredThe requirements for the test results shall be as follows:

5.19.1 Reduced-Section Tension Tests. The tensilestrength shall be no less than the minimum of the speci-fied tensile range of the base metal listed on the PQRform.

5.19.2 Root, Face, and Side Bend Tests. The convexsurface of the bend test specimen shall be visually exam-ined for discontinuities. For acceptance, the surface shallcontain no discontinuities exceeding the followingdimensions:

(1) 3 mm [1/8 in] measured in any direction on thesurface

(2) 10 mm [3/8 in] for the sum of the greatest dimen-sions of all discontinuities exceeding 1 mm [1/32 in], butless than or equal to 3 mm [1/8 in]

(3) 6 mm [1/4 in]—the maximum corner crack,except:

(a) When the corner crack resulted from a visualslag inclusion or other fusion-type discontinuity, the3 mm [1/8 in] maximum shall apply.

(b) Specimens with corner cracks exceeding6 mm [1/4 in] with no evidence of slag inclusions orother fusion-type discontinuities shall be disregarded anda replacement test specimen from the original weldmentshall be tested.

5.19.3 Macroetch Tests. For acceptable qualification,the macroetch test specimen, when inspected visually,shall conform to the following requirements:

5.19.3.1 PJP Groove Welds and Fillet Welds. Allwelds subject to the macroetch test shall conform to thefollowing requirements:

(1) No cracks

(2) Thorough fusion between adjacent layers of weldmetal and between weld metal and base metal

(3) Weld profiles conforming to design details butwith none of the variations prohibited in 3.6

(4) No undercut exceeding 1 mm [1/32 in]

(5) The designated weld size (PJP groove welds)

5.19.3.2 Fillet Weld Size and Fusion

(1) Minimum fillet weld leg size shall meet the speci-fied fillet weld size.

(2) Fillet welds shall have fusion to the root of thejoint, but not necessarily beyond.

5.19.4 All-Weld-Metal Tension Tests. The mechanicalproperties shall conform to the values specified in Table4.1 or 4.2, or as described in contract documents.

5.19.5 CVN Tests. CVN test results shall meet or exceedthe values specified in Table 4.1 or 4.2, or unless other-wise specified in the contract documents. Acceptanceshall be based on the following criteria:

5.19.5.1 SMAW, SAW, FCAW, and GMAW Speci-mens. For SMAW, SAW, FCAW, or GMAW speci-mens, the highest and lowest CVN test values shall bedisregarded, and the remaining three values shall beaveraged. For tests to be successful, the average of thethree remaining CVN test specimens energy values shallmeet or exceed the minimum specified CVN test energyvalue. No more than one specimen may have an impactenergy value less than the minimum specified and nospecimen shall have a value less than 2/3 of the mini-mum specified value.

5.19.5.2 ESW and EGW Specimens. For ESW orEGW welded specimens, the highest and lowest valuesshall be disregarded and the remaining six values shall beaveraged. For tests to be successful, the average of theremaining six CVN test values shall meet or exceed thespecified minimum CVN test energy value. No morethan two specimens may have an impact energy valueless than the minimum specified and no specimen shallhave a value less than 2/3 of the minimum specifiedvalue.

5.19.6 Visual Inspection. For acceptable qualification,the welded test plate when inspected visually shall con-form to the requirements for visual inspection in 6.26.1,except that undercut shall not exceed 1 mm [1/32 in].

5.20 Retests5.20.1 Tension and Bend. If any one specimen of allthose tested fails to meet the test requirements, tworetests for that particular type of test specimen may beperformed with specimens cut from the same WPS quali-fication test plate or a new plate conforming to the samespecification. The results of both test specimens shall meetthe test requirements. For material over 38 mm [1-1/2 in]thick, failure of a specimen shall require testing of allspecimens of the same type from two additional loca-tions in the test material.

5.20.2 CVN Test. When CVN test results do not meetthe requirements of 5.19.5, a retest may be made. Theimpact energy value of each of the required test speci-mens, after disregarding the highest and the lowest testvalues, shall equal or exceed the minimum specifiedCVN test energy average.

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Part BWelder, Welding Operator, and Tack

Welder Qualification

5.21 General RequirementsWelders, welding operators, and tack welders usingSMAW, SAW, GMAW, FCAW, ESW, and EGW weld-ing processes shall be qualified by the tests described inPart B.

5.21.1 Purpose. The qualification tests described in PartB are specially devised tests to determine the welder’s,welding operator’s, or tack welder’s ability to producesound welds.

The qualification tests are not intended to be used as aguide for welding during actual construction. Construc-tion welding shall be performed in conformance with therequirements of the WPS.

5.21.2 WPS Compliance. The welder, or welding opera-tor, shall follow a WPS applicable to the joint detailsgiven in 5.23.1.2, 5.23.1.3, 5.23.1.4, or 5.23.1.5, which-ever is applicable.

5.21.3 Base Metal. The base metal used shall be anAASHTO approved steel as described in 1.2.2 or theWPS (see 5.24.1.1).

5.21.4 Period of Effectiveness. The welder’s, weldingoperator’s, or tack welder’s qualification as described inthis code shall be considered as remaining in effectindefinitely unless (1) the welder, welding operator, ortack welder is not engaged in a given process of weldingfor which the welder, welding operator, or tack welder isqualified for a period exceeding six months, or unless (2)there is some specific reason to question a welder’s,welding operator’s or tack welder’s ability. In case of(1), the requalification test need be made only in the 10mm [3/8 in] thickness. If the welder fails a requalifica-tion test given in the case of (1), then full requalificationtesting shall be required, as if for a new welder.

5.21.5 Weld Cleaning

5.21.5.1 Chipping and Brushing. Cleaning betweenweld passes shall be limited to hand chipping and hand-wire brushing. Power chippers or grinders shall not beused during the weld test. Upon weld test completion andafter visual inspection, the weld may be made flush bypower tools as necessary in order to facilitate testing (see5.26.1.1).

5.21.5.2 Root and Fill Pass Cleaning. Root or inter-mediate weld bead contours shall not be modified by

chipping, grinding, cutting, or other means before depos-iting subsequent weld passes.

5.21.5.3 Cleaning Position. Weld cleaning shall bedone with the test weld in the same position as the weld-ing position being qualified.

5.21.6 Responsibility

5.21.6.1 Contractor. Each Contractor shall conducttests or verify that the welders, welding operators, andtack welders are qualified as required by this code.

5.21.7 Records. Records of the test results shall be keptby the manufacturer or Contractor and shall be availableto those authorized to examine them.

5.21.8 Previous Code Editions. Welders, welding oper-ators, and tack welders qualified to previous editions ofthis code shall be considered qualified to this code. Qual-ification test records shall not be required to be convertedto metric (SI) Units of measure if the tests were per-formed using U.S. Customary Units and vice versa.

5.22 Production Welding Positions Qualified

5.22.1 Welder Qualification (Groove Welds). SeeTable 5.6.

5.22.1.1 1G (Flat). Qualification in the 1G (flat) posi-tion shall qualify for flat position groove welding of plateand structural shapes, and flat and horizontal position fil-let welding of plate and structural shapes.

5.22.1.2 2G (Horizontal). Qualification in the 2G(horizontal) position shall qualify for flat and horizontalposition groove welding of plate and structural shapes,and flat and horizontal position fillet welding of plateand structural shapes.

5.22.1.3 3G (Vertical). Qualification in the 3G (ver-tical) position shall qualify for flat, horizontal, and verti-cal position groove welding of plate and structuralshapes; and flat, horizontal, and vertical position filletwelding of plate and structural shapes.

5.22.1.4 4G (Overhead). Qualification in the 4G(overhead) position shall qualify for flat and overheadposition groove welding of plate and structural shapesand flat, horizontal, and overhead position fillet weldingof plate and structural shapes.

5.22.2 Welder Qualification (Fillet Welds)

5.22.2.1 1F (Flat). Qualification in the 1F (flat) posi-tion shall qualify for flat position fillet welding of plateand structural shapes.

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5.22.2.2 2F (Horizontal). Qualification in the 2F(horizontal) position shall qualify for flat and horizontalposition fillet welding of plate and structural shapes.

5.22.2.3 3F (Vertical). Qualification in the 3F (verti-cal) position shall qualify for flat, horizontal, and verticalposition fillet welding of plate and structural shapes.

5.22.2.4 4F (Overhead). Qualification in the 4F(overhead) position shall qualify for flat, horizontal, andoverhead position fillet welding of plate and structuralshapes.

5.22.3 Welding Operator Qualification. Welding oper-ators shall qualify for each position of production welding.

5.22.4 Tack Welder Qualification. A tack welder whopasses the fillet weld break test shall be eligible to tackweld all types of groove joints and fillets using the pro-cess and the welding position tested.

5.23 Qualification Tests Required5.23.1 Welder Qualification. The welder qualificationtest for manual and semiautomatic welding shall con-form to the following requirements:

(1) Groove weld qualification tests for plate ofunlimited thickness in conformance with 5.23.1.2

(2) Groove weld qualification tests for plate of lim-ited thickness in conformance with 5.23.1.3

(3) Fillet weld qualification tests (for fillet weldingonly) in conformance with 5.23.1.4

(4) Plug weld qualification tests (for plug welds only)in conformance with 5.23.1.5

5.23.1.1 WPS Qualification. A welder who makes aCJP groove weld WPS qualification test that meets therequirements of this code is thereby qualified to weld bythat process in the positions qualified by the test position.The maximum thickness qualified is based upon testplate thickness as listed in Table 5.7. The limitations of5.21.5, Weld Cleaning, do not apply to a welder qualifiedby welding a satisfactory WPS qualification test plate.The welder shall also be qualified for fillet welding andslot welding of plate and shapes for the process and posi-tion tested.

5.23.1.2 Groove Weld Qualification Test for Plateof Unlimited Thickness. The joint details shall be as fol-lows: 25 mm [1 in] plate, single-V-groove, 45° includedangle, 6 mm [1/4 in] root opening with backing (seeFigure 5.17). For horizontal position qualification, thejoint detail may, at the Contractor’s option, be as fol-lows: single-bevel-groove, 45° groove angle, 6 mm

[1/4 in] root opening with backing (see Figure 5.18). IfRT is used, backing shall be 6 mm [1/4 in] min to 10 mm[3/8 in] by 75 mm [3 in]. For mechanical testing, backingmay be 6 mm [1/4 in] to 10 mm [3/8 in] by 25 mm [1 in]min. The minimum length of the welded groove shall be125 mm [5 in].

5.23.1.3 Groove Weld Qualification Test for Plateof Limited Thickness. The groove detail shall be as fol-lows: 10 mm [3/8 in] plate, single-V-groove, 45°included angle 6 mm [1/4 in] root opening with backing(see Figure 5.19). For horizontal position qualification,the joint detail may, at the Contractor’s option, be asfollows: single-bevel-groove 45° groove angle, 6 mm[1/4 in] root opening with backing (see Figure 5.20).Backing shall be 6 mm [1/4 in] min to 10 mm [3/8 in]max by 75 mm [3 in] min, if RT is used. For mechani-cal testing after the backing is removed, it shall be 6 mm[1/4 in] min to 10 mm [3/8 in] max by 25 mm [1 in]. Theminimum length of welding groove shall be 180 mm[7 in].

5.23.1.4 Qualification Tests for Fillet Welds Only.Requirements for fillet weld qualification only, on plateand rolled structural shapes, shall be as follows:

(1) For fillet welds between parts having a dihedralangle (Ψ) of less than 60°, the welder shall weld a grooveweld test plate as required by 5.23.1.2 or 5.23.1.3. Thisqualification shall also be valid for joints having a dihe-dral angle (Ψ) of 60° and greater.

(2) For joints having a dihedral angle (Ψ) of 60° orgreater, but not exceeding 135°, the welder shall weld atest plate according to Option 1 or Option 2, dependingupon the Contractor’s choice, as follows:

(a) Option 1. Weld a T-test plate in conformancewith Figure 5.21.

(b) Option 2. Weld a soundness test plate in con-formance with Figure 5.22.

5.23.1.5 Plug Weld Qualification Tests for PlugWelds Only. The joint shall consist of a 20 mm [3/4 in]diameter hole in a 10 mm [3/8 in] plate with a 10 mm[3/8 in] minimum thickness backing plate (see Figure5.23).

5.23.2 Welding Operator Qualification

5.23.2.1 Joint Requirements for Processes OtherThan ESW or EGW. The welding operator qualifica-tion test for other than plug welds and ESW or EGWwelding shall have a joint detail as follows: 25 mm [1 in]plate, single-V-groove, 20° included groove angle, 16 mm[5/8 in] root opening with backing. Backing shall be10 mm [3/8 in] to 12 mm [1/2 in] by 75 mm [3 in] minif RT is used without removal of backing. If backing is

PART B


96

removed, at least 40 mm [1-1/2 in] width of backingshall be used. The minimum length of welding grooveshall be 400 mm [15 in] (see Figure 5.24).

This test will qualify the welding operator for groove andfillet welding in materials of unlimited thickness for theprocess and position tested.

Alternatively, the welding operator may be qualified byRT of the initial 400 mm [15 in] of a production grooveweld. The material thickness range qualified shall be thatshown in Table 5.7.

5.23.2.2 Joint Requirements for ESW or EGW.The qualification test for an ESW or EGW welding oper-ator shall consist of welding a joint of the maximumthickness of material to be used in construction, but thethickness of the material of the test weld need not exceed38 mm (see Figure 5.25). If a 38 mm [1-1/2 in] thick testweld is made, no test need be made for lesser thick-nesses. This test shall qualify the welding operator forgroove and fillet welds in material of unlimited thicknessfor this process and test position.

5.23.2.3 WPS Qualification. A welding operatormay also be qualified by welding a satisfactory WPSqualification test plate, as described in 5.12 or 5.13, thatmeets the requirements of 5.19. That welding operatorshall be qualified to weld plate with the process and inthe test position used for WPS qualification. The limita-tions of 5.21.5 do not apply to a welding operator quali-fied by welding a satisfactory WPS qualification testplate. That welding operator shall also be qualified forslot welding for the process and position tested. Thethickness range qualified for shall be as described inTable 5.7.

5.23.2.4 Qualification Tests for Fillet Welds Only.Requirements for fillet weld qualification only, on plateand rolled structural shapes, shall conform to the follow-ing requirements:

(1) For fillet welds between parts having a dihedralangle (Ψ) of 60° or less, the welding operator shall welda groove weld test plate as required by 5.23.2. This qual-ification shall also be valid for joints having a dihedralangle (Ψ) of 60° and greater.

(2) For joints having a dihedral angle (Ψ) greaterthan 60°, but not exceeding 135°, the welding operatorshall weld a test plate in conformance with Option 1 orOption 2, depending upon the Contractor’s choice, asfollows:

(a) Option 1. Weld a T-test plate in conformancewith Figure 5.26.

(b) Option 2. Weld a soundness test plate in con-formance with Figure 5.27.

5.23.3 Tack Welder Qualification. A tack welder shallbe qualified by one fillet weld break specimen made ineach position in which tack welds are to be made. Thetack welder shall make a 6 mm [1/4 in] maximum sizetack weld approximately 50 mm [2 in] long on the filletweld break specimen, as shown in Figure 5.28.

5.24 Limitations of Variables

5.24.1 Common Requirements for Welders, WeldingOperators, and Tack Welders. The following require-ments shall apply to welder, welding operator, and tackwelder qualification (see 5.24.2 for specific limitationsfor welders, 5.24.3 for welding operators, and 5.24.4 fortack welders).

5.24.1.1 Base Metal. Qualification established withany one of the steels allowed by this code shall be con-sidered as qualification to weld or tack weld any of theother steels with the following exception:

Qualification to weld or tack weld steel with a minimumyield strength of 620 MPa [90 ksi] or greater shall beestablished with steel meeting the same specification assteel for the project.

5.24.1.2 Process. A welder, welding operator, or tackwelder shall be qualified for each process used.

5.24.1.3 Approved Electrode and ShieldingMedium. A welder, welding operator, or tack welderqualified with an approved electrode and shieldingmedium combination shall be considered qualified toweld or tack weld with any other approved electrode andshielding medium combination for the process used inthe qualification test.

5.24.2 Welder Qualification Variables Only. Theserequirements shall only apply to welder qualification.

5.24.2.1 SMAW Restrictions. A welder qualified forSMAW using EXX18 or EXX18-X electrodes shall bequalified to weld with all SMAW electrodes allowedunder this code, except welders required to use an elec-trode classification of E100XX-X or higher to join met-als with a minimum specified yield strength of 620 MPa[90 ksi] or greater shall be tested using E10018-X orE11018-X electrodes as necessary to match the yieldstrength of the base metal to be used in the work.

5.24.2.2 Position. A change in the position of weldingto one for which the welder is not already qualified shallrequire requalification. When the plate is in the verticalposition, change in the direction of welding shall requirerequalification (see Table 5.6).

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97

5.24.2.3 Backing. Omission of backing material (ifthe welder was qualified using backing) in CJP weldswelded from one side shall require requalification.

5.24.3 Welding Operator Qualification VariablesOnly. The following requirements shall only apply towelding operator qualification.

5.24.3.1 ESW/EGW. An ESW or EGW weldingoperator qualified with an approved electrode and shield-ing medium combination shall be considered qualified toweld with any other approved electrode and shieldingmedium combination for the process used in the qualifi-cation test.

5.24.3.2 Processes Other than ESW/EGW. Forother than ESW or EGW welding, a welding operatorqualified to weld with multiple electrodes shall be quali-fied to weld with a single electrode, but not vice versa.

5.24.3.3 Position. A change in the position in whichwelding of plate is done shall require requalification.

5.24.3.4 Machine Welder Qualification. Welders qual-ified for SAW shall be considered qualified for single-electrode machine welding in the same process(es)subject to the limitations of 5.24, provided the weldingoperators receive training and demonstrate their ability tomake satisfactory production welds.

5.24.4 Tack Welder Qualification Variables Only.The following requirements shall apply only to tackwelder qualification.

5.24.4.1 SMAW Restrictions. A tack welder quali-fied for SMAW using EXX18 electrodes shall be quali-fied to tack weld with all SMAW electrodes allowedunder this code. Tack welding shall be performed usingE7018 electrodes, unless the contract documents requiretack welding with electrodes classified E10018-X,E11018-X, or E12018-X. Tack welders shall be qualifiedfor the particular electrode used.

5.24.4.2 Position. A change in the position in whichtack welding is done shall require requalification.

5.25 Test Specimens: Number, Type, and Preparation

5.25.1 Welder Requirements. The type and number oftest specimens that shall be tested to qualify a welder bymechanical testing are shown in Table 5.7, together withthe range of thickness that is qualified for use in con-struction by the thickness of the test plate used in makingthe qualification. RT of the test weld may be used, at theContractor’s option in lieu of mechanical testing. RT

shall not be an option for GMAW-S. Weld backing shallnot be removed from welds subject to RT.

5.25.2 Welding Operator Requirements. For mechani-cal testing, guided bend test specimens shall be preparedby cutting the test plate as shown in Figure 5.24, 5.25, or5.27, whichever is applicable, to form specimens approx-imately rectangular in cross section. The specimens shallbe prepared for testing in conformance with Figure 5.11or 5.12, as applicable.

5.25.3 Tack Welder Requirements. One test specimenshall be welded as shown in Figure 5.28 with the entirewelded assembly as the test specimen.

5.26 Method of Testing Specimens5.26.1 Radiographic Testing. Except for joints weldedby GMAW-S, RT of welder and welding operator quali-fication test plates may be made in lieu of guided bendtests described in Part B of this section (see 4.14.4 forclarification of short-circuiting transfer).

5.26.1.1 Weld Reinforcement. If RT is used in lieuof the prescribed bend test, the weld reinforcement shallbe ground flush or finished with slight reinforcement sothat there are no lines or surface irregularities that mayobscure discontinuities in the radiograph. Weld backingshall not be removed from welds subject to RT.

5.26.1.2 RT Procedure for Welder Qualification.The RT procedure and technique shall be in conformancewith the requirements of Clause 6, Part B. Exclude 30 mm[1-1/4 in] at each end of the weld from evaluation in theplate test.

5.26.1.3 RT Procedure for Welding OperatorQualification. The RT procedure and technique shall bein conformance with the requirements of Clause 6, PartB. At each end of the length of the test plate, 75 mm[3 in] shall be excluded from evaluation.

5.26.2 Guided Bend Test for Welder Qualification.Guided bend test specimens shall be prepared by cuttingthe test plate as shown in Figures 5.17, 5.18, 5.19, 5.20,whichever are applicable, to form specimens approxi-mately rectangular in cross section. The specimens shallbe prepared for testing in conformance with Figures 5.11or 5.12, as applicable.

5.26.2.1 Root, Face, and Side Bend Specimens. See5.18.3 for specimen requirements.

5.26.3 Fillet Weld Break and Macroetch TestRequirements

5.26.3.1 Welder Qualification. The fillet weld breakand macroetch test specimens shall be cut from the test

PART B


98

joint, as shown in Figure 5.21. The end of the macroetchtest specimen shall be smooth for etching. The entirelength of the fillet weld shall be examined visually andthen the 150 mm [6 in] specimen shall be loaded in sucha way that the root of the weld is in tension. The loadshall be steadily increased or repeated until the specimenfractures or bends flat upon itself.

5.26.3.2 Welding Operator Qualification. The filletweld break and macroetch test specimens shall be cutfrom the test joint as shown in Figure 5.26. The end ofthe macroetch test specimen shall be smooth for etching.The entire length of the fillet weld shall be examinedvisually and then a 150 mm [6 in] long specimen shall beloaded in such a way that the root of the weld is in ten-sion. The load shall be steadily increased or repeateduntil the specimen fractures or bends flat upon itself.

5.26.3.3 Tack Welder Qualification. A force shallbe applied to the specimen as shown in Figure 5.29, untilrupture occurs. The force may be applied by any conve-nient means. The surface of the weld and of the fractureshall be examined visually for defects.

5.26.3.4 Macroetch Test. The test specimens shall beprepared with a finish suitable for macroetch examina-tion. A suitable solution shall be used to give a clear def-inition of the weld.

5.27 Test Results Required5.27.1 Visual Inspection of Welder and WeldingOperator Test Plates. For acceptable qualification, thewelded test plates, when inspected visually, shall con-form to the requirements for visual inspection in 6.26.1,except that undercut shall not exceed 1 mm [1/32 in].Weld reinforcement shall not exceed 5 mm [3/16 in].

5.27.2 RT. For acceptable qualification, the weld, asrevealed by the radiograph, shall conform to the require-ments of 6.26.2, except that 6.26.2.2 shall not apply.

5.27.3 Root or Side Bend Tests. The convex surface ofthe bend test specimen shall be visually examined forsurface discontinuities. For acceptance, the surface shallcontain no discontinuities exceeding the followingdimensions:

(1) 3 mm [1/8 in] measured in any direction on thesurface

(2) 10 mm [3/8 in] for the sum of the greatest dimen-sions of all discontinuities exceeding 1 mm [1/32 in], butless than or equal to 3 mm [1/8 in]

(3) 6 mm [1/4 in]—the maximum corner crack,except when that corner crack resulted from visible slag

inclusion or other fusion-type discontinuities, then the3 mm [1/8 in] maximum shall apply

Specimens with corner cracks exceeding 6 mm [1/4 in]with no evidence of slag inclusions or other fusion-typediscontinuities may be disregarded, and a replacementtest specimen from the original weldment shall be tested.

5.27.4 Fillet Weld Break Test (Welder and WeldingOperator)

5.27.4.1 Visual Examination. To pass the visualexamination, the fillet weld shall present a reasonablyuniform appearance and shall be free of overlap, cracks,and excessive undercut. There shall be no porosity visi-ble on the surface of the weld.

5.27.4.2 Fracture Surface. The specimen shall passthe test if it bends flat upon itself. If the fillet weld frac-tures, the fractured surface shall show complete fusioninto the root of the joint and shall exhibit no inclusion orporosity larger than 2 mm [1/16 in] in the greatest dimen-sion. The sum of the greatest dimensions of all inclusionsand porosity shall not exceed 10 mm [3/8 in] in the 150 mm[6 in] specimen.

5.27.5 Fillet Weld Break Test (Tack Welder)

5.27.5.1 Visual Examination. The tack weld shallpresent a uniform appearance and shall be free of over-lap, cracks, and excessive undercut exceeding 1 mm[1/32 in]. There shall be no porosity visible on the sur-face of the tack weld.

5.27.5.2 Fracture Surface. The fracture surface ofthe tack weld shall show fusion to the root but not neces-sarily beyond and shall exhibit no incomplete fusion tothe base metal nor any inclusion or porosity larger than2 mm [1/16 in] in greatest dimension.

5.27.6 Macroetch Test. For acceptable qualification, thetest specimen, when inspected visually, shall conform tothe following requirements:

5.27.6.1 Fillet Welds. Fillet welds shall conform tothe following requirements:

(1) No cracks

(2) Thorough fusion between adjacent layers of weldmetals and between weld metal and base metal

(3) Weld profiles conforming to intended detail, butwith none of the variations prohibited in 3.6

(4) No undercut exceeding 1 mm [1/32 in]

(5) Fusion to the root of the joint but not necessarilybeyond

(6) Leg sizes equal to or greater than the specified legsize

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99

5.27.6.2 Plug Welds. Plug welds shall conform to thefollowing requirements:

(1) No cracks

(2) Thorough fusion to backing plate and to sides ofthe hole

(3) No visible slag in excess of 6 mm [1/4 in] totalaccumulated length

5.28 Retests5.28.1 Welder and Welding Operator. If a welder orwelding operator fails to meet the requirements of one or

more test welds, a retest may be allowed under the fol-lowing conditions:

5.28.1.1 Immediate Retest. An immediate retest maybe made consisting of two test welds of each type andposition that the welder or welding operator failed. Allretest specimens shall meet all the specified require-ments.

5.28.1.2 Retest After Further Training or Practice.A retest may be made provided there is evidence that thewelder or welding operator has had further training orpractice. A complete retest of the types and positionsfailed shall be made.

5.28.2 Tack Welder. In case of failure to pass the fil-let weld break test, the tack welder may make one retestwithout additional training.

PART B

100


Table 5.1WPS Qualification Requirements for Consumables (see 5.5.1)

Consumables

Process

FCAW SAW GMAW SMAW ESW EGW

Each AWS filler metal classification X X X X X X

Each manufacturer’s brand and type of cored electrode

X X X X X

Each manufacturer’s brand and type of flux X X

Each shielding gas or combination of shielding gasesa

X X X

a Differences of 25% or less in the minor element of the mixture proportions shall not require separate tests.

Note: An “X” indicates applicability for the process; a shaded block indicates nonapplicability.

Table 5.2WPS Qualification or Prequalification Options (see 5.9)

Joint Detail(s) Process(es)Filler Metals

Listed in Table(s):Qualification Options

per Subclause(s):

Groove detail conforming toFigure 2.4 or 2.5

SMAW4.1 5.11

4.2 5.13

FCAW-G, SAW, GMAWa4.1 5.12.1, or 5.12.2, or 5.13

4.2 5.13

FCAW-S, GMAW, EGW, ESW 4.2 5.13

Any groove detail not conforming to Figure 2.4 or 2.5

SMAW, SAW, FCAW (-G and -S), GMAW, EGW, ESW

4.1 or 4.2 5.13

Fillet WeldsSMAW, SAW, FCAW (-G and -S)

GMAW, EGW, ESW4.1 or 4.2 5.10

a Metal-cored electrodes only.

101


Table 5.3PQR Essential Variable Changes for WPSs Qualified per 5.13.3

Essential Variable Changes to PQR Requiring Requalification

Process

Shielded MetalArc Welding

(SMAW)

SubmergedArc Welding

(SAW)

Gas MetalArc Welding

(GMAW)

Flux CoredArc Welding

(FCAW)

ElectroslagWelding(ESW)

ElectrogasWelding(EGW)

Filler Metal

1) Addition or deletion of supplemental powdered or granular filler metal or cutwire

X

2) Increase or decrease in the amount of supplemental powdered or granular filler metal or wire

X

3) If the alloy content of the weld metal is largely dependent on supplemental powdered filler metal, any WPS change that results in a weld deposit with the important alloying elements not meeting the WPS chemical composition requirements

X

4) A change in the ratio of supplemental powdered, granular filler metal, orcut wire to electrode

X

Electrode

5) Increase or decrease in electrode diameter by more than one standard size

X X X X X X

6) Change in number of electrodes

X X X X X X

7) A change in the amperage by:

To a value not recommended

by the electrode manufacturer

>10%increase or decrease





8) A change in type of current (AC or DC) or polarity

X X X X X X

9) A change in mode transfer (see 5.12 and Annex C)

X

10) A change in the voltage by:>7%

increase or decrease



(Continued)

102


11) For WPSs using alloy or active fluxes, any increase in the maximum voltage

X

12) A change in the travel speed by:




>20%increase or 2decreaseb

>20%increase or 2decreaseb

13) An increase in heat input by more than 10% or decrease of more than 30%b

X X X X X X

Gas Shielding

14) Any increase of 25% or more or decrease of 10% or more in total gas flow

X X X

Multiple Electrode SAW

15) A change >10%, or 3 mm[1/8 in], whichever is greater, in the longitudinal spacing of the arcs

X

16) A change of >10%, or 2 mm [1/16 in], whichever is greater, in the lateral spacing of the arcs

X

17) An increase or decrease of more than 10° in the angular orientation of any parallel electrode

X

18) For machine or automatic SAW; an increase or decrease of more than 3° in the direction of travel

X

19) For machine or automatic SAW, an increase or decrease of more than 5° normal to the direction of travel

X

General

20) For the PQR groove area, an increase or decrease >25% in the number of passesa, c

X X X X X X

Table 5.3 (Continued)PQR Essential Variable Changes for WPSs Qualified per 5.13.3


Process


(SMAW)


(SAW)


(GMAW)


(FCAW)



(Continued)

103


21) A change from a U-grooveto a V-groove (but notvice versa)

X X X X

22) A change in the type of groove to a square groove and vice versa

X X X X

23) A change exceeding the tolerances of 2.12, 2.13, or 3.3.4 in the shape of any type of groove involving:(a) A decrease in the groove

angle(b) A decrease in the root

opening(c) An increase in the root

face which will not be subsequently removed by backgouging

X X X X

24) The omission, but not inclusion, of backing or backgouging

X X X X

25) Addition or deletion ofPWHT

X X X X X X

26) For M270M [M270] (A 709M [A 709]), Gr. 690 [100], 690W [100W], increase in plate thickness greater than 12 mm [1/2 in] or decrease of 25 mm [1 in] or more

X X X X

a If the production weld groove area differs from that of the PQR groove area, the number of passes may be changed in proportion to the area withoutrequiring WPS requalification.

b For M270M [M270] (A 709M [A 709]) Gr. 690 [100], 690W [100W], allowable heat input increase or decrease shall be limited to 10%.c For M270M [M270] (A 709M [A 709]) Gr. 690 [100], 690W [100W], passes any change in the number of groove weld passes requires requalification,

except proportional changes to accommodate a change in weld cross-sectional area. For fillet welds in these steels, any change in the number of passesrequires a fillet weld T-test per Figure 5.8 to be performed.

Notes:1. An “X” indicates applicability for the process; a shaded block indicates nonapplicability.2. The production welding preheat or interpass temperature may be less than the PQR preheat or interpass temperature provided that the provisions of

Table 4.4 or Annex G are met.3. Solid wire electrodes conforming to the same AWS filler metal classification may be interchanged without requalification (see Table 5.1).4. These limitations apply for travel speed changes that are not an automatic function of arc length or deposition rate, and are not applicable when it

necessary to compensate for variation in joint opening as approved by the Engineer.5. See 5.5.1 for additional WPS qualification requirements.

Table 5.3 (Continued)PQR Essential Variable Changes for WPSs Qualified per 5.13.3


Process


(SMAW)


(SAW)


(GMAW)


(FCAW)



104


Table 5.4Additional PQR Essential Variable Changes

Requiring WPS Requalification for ESW or EGW (see 5.14.2)

Essential Variable Changes to PQR Requiring RequalificationRequalificationby WPS Test

Requalificationby Radiographic or

Ultrasonic Testa

Molding Shoes (fixed or movable)

1) A change from metallic to nonmetallic or vice versa X

2) A change from fusing to nonfusing or vice versa X

3) A reduction in any cross-sectional dimension or area of a solid nonfusing shoe >25%

X

4) A change in design from nonfusing solid to water cooled or vice versa X

Filler Metal Oscillation

5) A change in oscillation traverse speed >4 mm/s [10 in/min] X

6) A change in oscillation traverse dwell time >2 s (except as necessaryto compensate for joint operating variations—as approved by theEngineer)

X

7) A change in oscillation traverse length which affects by more than 3 mm [1/8 in], the proximity of filler metal to the molding shoes

X

Filler Metal Supplements

8) A change in consumable guide metal core cross-sectional area >30% X

9) A change in the flux system, i.e., cored, magnetic electrode, external, etc.

X

10) A change in flux composition including consumable guide coating X

11) An increase or decrease in flux burden exceeding 30% X

Process Characteristics

12) A change to a combination with any other welding process X

13) A change from single pass to multi-pass and vice versa X

14) A change from constant current to constant voltage and vice versa X

Wire Feed Speed

15) An increase or decrease in the wire feed speed >40% X

Groove Type

16) A change in groove design, reducing cross-sectional area(for nonsquare grooves)

X

17) A change in WPS joint thickness, outside limits of 0.5T –1.1T(T = qualification thickness)

X

18) An increase or decrease >6 mm [1/4 in] in square groove root opening X

a Testing shall be performed in conformance with Clause 6, Part E or F, as applicable.

Note: An “X” indicates applicability for the requalification method; a shaded block indicates nonapplicability.

105


Table 5.5Required Number of Test Specimens—WPS Qualification (see 5.16.3)

Test Plate Figure

All WeldMetal

Tension TestReduced Section

Tension TestSide Bend

TestCVNTest

Groove Weld Macroetch

Test

Fillet Weld Macroetch

Test

5.15.25.35.8

11

——

2—2

—

424

—

a5a

5——

(Note b)—2—

———3

a Eight CVN tests shall be required for ESW and EGW.b When required by the Engineer.

Table 5.6Welder Qualification—Type and Position Limitations (see 5.22)

Qualification Test

Type of Weld and Position of Welding Qualified

Plate

Weld Positions Groove Fillet

Plate-groove

1G2G3G4G

3G and 4G

FF, H

F, H, VF, OH

All

F, HF, H

F, H, VF, H, OH

All

Plate-filleta

1F2F3F4F

3F and 4F

FF, H

F, H, VF, H, OH

All

Plate-Plugb1F3F4F

FV

OH

a Not applicable for fillet welds between parts having a dihedral angle (Ψ) of 60° or less (see 5.23.1.4).b Applicable only to qualification of plug welds (see 5.23.1.5).

106


Table 5.7Number and Type of Specimens and Range of Thickness Qualified—

Welder and Welding Operator Qualification (see 5.25.1)

1. Test on Plate

Type of Weld

Thickness of Test

Plate (T) as Welded,mm [in]

Visual Inspection

Number of SpecimensPlate

Thickness Qualified,mm [in.]

Bend Testse

T-JointBreak

Macro-Etch TestFace Root Side

Groovef 10 [3/8] Yes 1 1 — — —20 [3/4] max.c, g

Groove10 < T < 25[3/8 < T < 1]

Yes — — 2 — — 2Tc, d max.

Groove 25 [1] or over Yes — — 2 — — 0Unlimitedc

Fillet Option No. 1a 12 [1/2] Yes — — — 1 1 Unlimited

Fillet Option No. 2b 10 [3/8] Yes — 2 — — — Unlimited

Plug 10 [3/8] Yes — — — — 2 Unlimited

2. Tests on Electroslag and Electrogas Welding

Plate ThicknessTested, mm [in]

Test Specimens Required

Plate Thickness Qualified,mm [in]

Number ofSample Welds

VisualInspection

Side Bende

(see Figure 5.23)

38 [1-1/2] max. 1 Yes 2Unlimited for 38 [1-1/2]

Max. tested for <38 [1-1/2]a See Figure 5.21.b See Figure 5.22.c Also qualifies for fillet welding on material of unlimited thickness.d T max. for welding operator qualification.e RT of test plate may be made in lieu of the bend test. This shall not be allowed for GMAW-S.f Not applicable for welding operator qualification.g See Figures 5.19 and 5.20.

107


Notes:1. Welding and machining shall be witnessed by a state representative or an independent third party acceptable to the state.2. Test specimens and the PQR showing all welding parameters used for the test shall be available to the Engineer. Test specimens

need only be retained for examination by the original approving authority.3. The joint detail to be used shall be either a B-U2a, B-U2-S, B-U2a-GF, B-U4a, or B-U4a-GF detail, depending on the welding process

used and the position of the welding, except that the B-U2a-GF and B-U4a-GF with the 5 mm [3/16 in] root opening and 30° includedangle shall not be used.

Figure 5.1—WPS Qualification or Pretest—Test Plate A (see 5.7.1)

108


Notes:1. Test specimens need only be retained for examination by the original approving authority.Welding and machining shall be witnessed

by a state representative or an independent third party acceptable to the state.2. Test specimens and the PQR showing all welding parameters used for the test shall be available to the Engineer. Test specimens

need only be retained for examination by the original approving authority.3. Testing shall be done by an approved testing laboratory. Such testing need not be witnessed by another agency.4. The joint detail to be used shall be either a B-U2a, B-U2-S, B-U2a-GF, B-U4a, or B-U4a-GF detail, depending on the welding process

used and the position of the welding, except that the B-U2a-GF and B-U4a-GF with the 5 mm [3/16 in] root opening and 30° includedangle shall not be used.

Figure 5.2—WPS Verification—Test Plate B (see 5.7.3)

109


a Macroetch specimens 10 mm [3/8 in] thick and “T” wide shall be polished and etched for macroscopic examination by the Engineer.

Notes:1. Welding and machining shall be witnessed by a state representative or an independent third party acceptable to the state.2. Test specimens and the PQR showing all welding parameters used for the test shall be available to the Engineer. Test specimens

need only be retained for examination by the original approving authority.3. Testing shall be done by an approved testing laboratory. Such testing need not be witnessed by another agency.

Figure 5.3—Weld Soundness Test Plate for Details Not Conforming toFigure 2.4 or 2.5—Test Plate C (see 5.7.7)

110


Notes:1. The horizontal reference plane shall always be taken to lie below the weld under consideration.2. The inclination of axis shall be measured from the horizontal reference plane toward the vertical reference plane.3. The angle of rotation of the face shall be determined by a line perpendicular to the theoretical face of the weld which passes through

the axis of the weld. The reference position (0°) of rotation of the face invariably points in the direction opposite to that in which theaxis angle increases. When looking at point P, the angle of rotation of the face of the weld shall be measured in a clockwise directionfrom the reference position (0°).

Figure 5.4—Positions of Fillet Welds (see 5.8.1)

Tabulation of Positions of Fillet Welds

Position Diagram Reference Inclination of Axis Rotation of Face

Flat A 0° to 15° 150° to 210°

Horizontal B 0° to 15° 125° to 150°210° to 235°

Overhead C 0° to 80° 0° to 125°235° to 360°

Vertical DE

15° to 80°80° to 90°

125° to 235°0° to 360°

111


Notes:1. The horizontal reference plane shall always be taken to lie below the weld under consideration.2. The inclination of axis shall be measured from the horizontal reference plane toward the vertical reference plane.3. The angle of rotation of the face shall be determined by a line perpendicular to the theoretical face of the weld which passes through

the axis of the weld. The reference position (0°) of rotation of the face invariably points in the direction opposite to that in which theaxis angle increases. When looking at point P, the angle of rotation of the face of the weld shall be measured in a clockwise directionfrom the reference position (0°).

Figure 5.5—Positions of Groove Welds (see 5.8.1)

Tabulation of Positions of Groove Welds

Position Diagram Reference Inclination of Axis Rotation of Face

Flat A 0° to 15° 150° to 210°

Horizontal B 0° to 15° 80° to 150°210° to 280°

Overhead C 0° to 80° 0° to 80°280° to 360°

Vertical DE

15° to 80°80° to 90°

80° to 280°0° to 360°

112


Figure 5.6—Position of Test Plates for Groove Welds (see 5.8.2)

113


Figure 5.7—Position of Test Plates for Fillet Welds (see 5.8.3)

114


Notes:1. Where the maximum plate thickness used in production is less than the value shown in the table, the maximum thickness of the

production pieces may be substituted for T1 and T2.2. At the contractor’s option, the maximum single pass fillet welds may be welded on one side of the joint, and the minimum multiple

pass fillet weld may be welded on the other side.

Figure 5.8—Fillet Weld Soundness Test (Macroetch) for WPS Qualification—Test Plate D (see 5.10.3)

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Notes:1. The reduced section may have a gradual taper from the ends toward the center with the ends not more than 0.1 mm [0.005 in] larger in

diameter than the center.2. The all-weld metal tension specimen shall be taken from the center of the thickness of the weld, and from the center of the width of

the weld at this location.

Figure 5.9—Standard Round All-Weld-Metal Tension Specimen (see 5.16.3)

Notes:1. T depends on the thickness of test plate shown in Figure 5.1 or 5.3; see 5.6.2. L shall be the overall length of the test specimen. The length shall be sufficient to facilitate gripping in the testing apparatus. When

practicable, the specimen should extend into the grips a distance greater than or equal to 2/3 the length of the grip.3. Weld reinforcement and steel backing, if any, shall be removed flush with the surface of the specimen.

Figure 5.10—Reduced Section Tension Specimen (see 5.16.3)

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a T depends on the thickness of test plate shown in Figures 5.1, 5.2, and 5.3; see 5.6. If T > 40 mm [1-1/2 in], see AWS B4.0, Figure A5,Notes 1 and 2, for guidance on cutting the specimen into strips between 20 mm and 40 mm [3/4 in to 1-1/2 in] wide.

Figure 5.11—Side-Bend Specimen (see 5.16.3)

Figure 5.12—Face- and Root-Bend Specimen (see 5.16.3)

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Figure 5.13—CVN Test Specimen—Type A (see 5.16.4)

Note: Allowable variations shall be as follows:

Notch perpendicularity to edgeAdjacent sidesCross section dimensionsLength of specimen (L)Centering of notch (L/2)

Angle of notchRadius of notchDepth of notchFinish requirements

90° ± 2°90° ± 10 min.±0.075 mm [±0.003 in]±0, –2.5 mm [–0.100 in]±1 mm [0.04 in]: When an end-centering device is necessary to center the specimenin the anvil (see 8.3.2, ASTM E 23, Standard Methods for Notched Bar Impact Testingof Metallic Materials), it shall be necessary that the notch be accurately centered toensure compliance with A1.10.2 (ASTM E 23)±1°±0.025 mm [±0.001 in]±0.025 mm [±0.001 in]2 µm [63 µin] on notched surface and opposite face; 4 µm [125 µin] on other two surfaces

Note: Five test specimens shown, eight required for ESW and EGW.

118


Figure 5.14—Guided Bend Test Jig (see 5.18.3)

Minimum Specified Base Metal Yield Strength, MPa [ksi]

Amm [in]

Bmm [in]

Cmm [in]

Dmm [in]

345 [50] and under 38.1 [1-1/2] 19.0 [3/4] 60.3 [2-3/8] 30.2 [1-3/16]

Over 345 [50] to 620 [90] 50.8 [2]0-0 25.4 [1]0/ 73.0 [2-7/8] 36.6 [1-7/16]

620 [90] and over 63.5 [2-1/2] 1-31.8 [1-1/4] 85.7 [3-3/8] 42.9 [1-11/16]

Notes:1. Plunger and interior die surfaces shall be machine-finished.2. The diameter A of the plunger shall equal or exceed the weld face width (after machining). If this requirement cannot

be met, see AWS B4.0M or B4.0 for guidance on adjusting the specimen thickness and fixture dimensions.

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Figure 5.15—Alternate Wraparound Guided Bend Test Jig (see 5.18.3)


Amm [in]

Bmm [in]

345 [50] and under 38.1 [1-1/2] 19.0 [3/4]-0

Over 345 [50] to 620 [90] 50.8 [2]0-0 25.4 [1]0-0

620 [90] and over 63.5 [2-1/2] 31.8 [1-1/4]

Notes:1. Minimum roller length shall be 50 mm [2 in].2. Diameter A shall equal or exceed the weld face width (after machining). If

this requirement cannot be met, see AWS B4.0M or B4.0 for guidance onadjusting the specimen thickness and fixture dimensions.

120


Figure 5.16—Alternate Roller-Equipped Guided Bend Test Jig forBottom Ejection of Test Specimen (see 5.18.3)


Amm [in]

Bmm [in]

Cmm [in]

345 [50] and under 38.1 [1-1/2] 19.0 [3/4]-0 60.3 [2-3/8]

Over 345 [50] to 620 [90] 50.8 [2]0--0 25.4 [1]0-0 73.0 [2-7/8]

620 [90] and over 63.5 [2-1/2] 31.8 [1-1/4] 85.7 [3-3/8]

Notes:1. Minimum roller length (or shoulder width) shall be 50 mm [2 in].2. Diameter A shall equal or exceed the weld face width (after machining). If this requirement

cannot be met, see AWS B4.0M or B4.0 for guidance on adjusting the specimen thicknessand fixture dimensions.

121


a The backing thickness shall be 6 mm [1/4 in] min. to 10 mm [3/8 in] max.; backing width shall be 75 mm [3 in] min.when not removed for RT, otherwise 25 mm [1 in] min.

Note: When RT is used for testing, no tack welds shall be in test area.

Figure 5.17—Test Plate for Unlimited Thickness—Welder Qualification (see 5.23.1.2)

122


Figure 5.18—Optional Test Plate for Unlimited Thickness—Horizontal Position—Welder Qualification (see 5.23.1.2)

123


Figure 5.19—Test Plate for Limited Thickness—All Positions—Welder Qualification (see 5.23.1.3)

a The backing thickness shall be between 6 mm [1/4 in] min. and 10 mm[3/8 in] max.; backing width shall be 75 mm [3 in] max. for RT and 25 mm[1 in] min. for mechanical testing.

Note: When RT is used, no tack welds shall be in test area. Weld backingshall not be removed.

Figure 5.20—Optional Test Plate for Limited Thickness—Horizontal Position—Welder Qualification (see 5.23.1.3)

124


Note: Plate thickness and dimensions are minimum.

Figure 5.21—Fillet-Weld-Break and Macroetch Test Plate—Welder Qualification—Option 1 (see 5.23.1.4)

125


Figure 5.22—Fillet Weld Root-Bend Test Plate—Welder Qualification—Option 2 (see 5.23.1.4)

126


Figure 5.23—Plug Weld Macroetch Test Plate—Welder Qualification (see 5.23.1.5)

127


a The backing thickness shall be 10 mm [3/8 in] min. to 12 mm [1/2 in] max.; backing width shall be 75 mm [3 in] min. when not removedfor RT, otherwise 40 mm [1-1/2 in].

Notes:1. When RT is used for testing, no tack welds shall be in test area.2. The joint configuration of a qualified groove WPS may be used in lieu of the groove configuration shown here.

Figure 5.24—Test Plate for Unlimited Thickness—Welding Operator Qualification (see 5.23.2.1)

128


Notes:1. Root opening “R” established by WPS.2. T = maximum to be welded in construction but need not exceed 38 mm [1-1/2 in].3. Extensions need not be used in joint is of sufficient length to provide 450 mm [17 in] of sound weld.

Figure 5.25—Butt Joint for Welding Operator Qualification—ESW and EGW (see 5.23.2.2)

129


Note: Plate thickness and dimensions are minimum.

Figure 5.26—Fillet-Weld-Break and Macroetch Test Plate—Welding Operator Qualification—Option 1 (see 5.23.2.4)

130


Figure 5.27—Fillet Weld Root Bend Test Plate—Welding Operator Qualification—Option 2 (see 5.23.2.4)

131


Figure 5.28—Fillet-Weld-Break Specimen—Tack Welder Qualification (see 5.25.3)

Figure 5.29—Method of RupturingSpecimen—Tack Welder Qualification

(see 5.26.3.3)


132



133


6.1 General6.1.1 For the purpose of this code, quality control (QC)inspection and testing and quality assurance (QA) inspec-tion and testing shall be considered separate functions.

6.1.1.1 QC shall be the responsibility of the Contrac-tor. As a minimum, the Contractor shall perform inspec-tion and testing prior to assembly, during assembly,during welding and after welding as described in thissection and additionally as necessary to assure that mate-rials and workmanship conform to the requirements ofthe contract documents.

6.1.1.2 QA shall be the prerogative of the Engineer.The Engineer should perform inspection and testingnecessary to verify that an acceptable product is being fur-nished as specified in the contract documents. QA inspec-tion and testing should be performed and reported in amanner that will minimize interference with production.

6.1.2 Inspector—Definition

6.1.2.1 The QC Inspector shall be the duly designatedperson who acts for and in behalf of the Contractor oninspection, testing, and quality matters within the scopeof the contract documents. When there are several per-sons performing QC inspection and testing, a supervisinginspector shall be designated as the QC Inspector.

6.1.2.2 The QA Inspector shall be the duly designatedperson who acts for and on behalf of the Engineer andOwner on all matters within the scope of the contractdocuments and the limit of authority delegated by theEngineer.

6.1.2.3 The term Inspector, when used without furtherqualification, shall apply equally to QC and QA asdefined in 6.1.2.1 and 6.1.2.2.

6.1.3 Inspection Personnel Qualification

6.1.3.1 All Inspectors responsible for QC and QAacceptance or rejection of materials and workmanshipshall be qualified as follows:

(1) The Inspector shall be an AWS Certified WeldingInspector (CWI) qualified and certified in conformancewith the provisions of AWS QC1, Standard and Guide forQualification and Certification of Welding Inspectors, or

(2) The Inspector shall be qualified by the CanadianWelding Bureau (CWB) to the requirements of theCanadian Standard Association (CSA) standard W178.2,Certification of Welding Inspectors.

NOTE: Welding Inspectors qualified by the CanadianWelding Bureau (to the Level II or the Level III require-ments of the Canadian Standards Association standardW178.2, Certification of Welding Inspectors, are ac-knowledged by AWS as being qualified under the provi-sions of AWS QC1. It shall be the policy of the StructuralWelding Committee to recognize welding Inspector cer-tification programs that are substantially the same asoffered by AWS and CWB. Such programs, public or pri-vate, shall be competently administered, be reasonablyspecified, and be open to the public. When so constituted,such certification programs shall be considered equiva-lent to AWS and CWB programs,

or

(3) The Inspector shall be an engineer or technicianwho, by training and experience in metals fabrication,inspection and testing, is acceptable to the Engineer as anequivalent to (1) or (2).

6.1.3.2 An Inspector, previously certified as a weldingInspector under the provisions of AWS QC1 or CSAstandard W178.2, Level II or III, may serve as an Inspec-tor for this work, provided there is acceptable documen-tation that the Inspector has remained active as anInspector of welded structural steel fabrication since lastbeing certified and there is no reason to question theInspector’s ability.

6. Inspection

CLAUSE 6. INSPECTION AASHTO/AWS D1.5M/D1.5:2008

134

6.1.3.3 The Inspector may be supported by AssistantInspectors who may perform specific inspection functionsunder the supervision of the Inspector. AssistantInspectors shall be qualified by training and experience toperform the specific functions to which they are assigned.The work of Assistant Inspectors shall be regularly moni-tored, generally on a daily basis, by the Inspector.

6.1.3.4 Personnel Qualification. Personnel perform-ing NDT, other than visual examination, shall be certi-fied in conformance with the American Society forNondestructive Testing’s (ASNT) Recommended Prac-tice No. SNT-TC-1A, or an equivalent satisfactory to theEngineer. Certification of Level I and Level II individu-als shall be performed by the ASNT Central CertificationProgram (ACCP), or a Level III individual who has beencertified by (1) ASNT, or (2) has the education, training,experience, and has successfully passed the writtenexamination prescribed in ASNT SNT-TC-1A. Individualswho perform NDT shall be certified as:

(1) NDT Level II, or

(2) NDT Level I working under the direct supervi-sion of an individual qualified for NDT Level II or NDTLevel III.

(3) NDT Level III and qualified per ASNT SNT-TC-1A as a Level II for NDT performed.

6.1.3.5 The Engineer shall have the authority to verifythe qualifications of QC Inspectors and NDT personnelto specified levels by retests or other means.

6.1.3.6 Personnel performing NDT per 6.1.3.4 neednot be qualified per 6.1.3.1 but shall have adequatevision per 6.1.3.7.

6.1.3.7 Inspectors, Assistant Inspectors, and personnelperforming NDT shall have passed an eye examination,with or without corrective lenses, to prove (1) near visionacuity of Snellen English, or equivalent, at 300 mm[12 in], and (2) far vision acuity of 20/40 or better.Vision tests shall be required every three years, or less ifnecessary, to demonstrate adequacy.

6.1.4 The Inspector shall be furnished complete detaileddrawings showing the size, length, type, and location ofall welds to be made. The Inspector shall be furnishedwith the portion of the contract documents whichdescribes material and quality requirements for the prod-ucts to be fabricated or erected, or both.

6.1.5 The Inspector shall be notified in advance of thestart of fabrication/erection operations subject to inspec-tion and verification.

6.2 Inspection of MaterialsThe Inspector shall make certain that only materials con-forming to the requirements of the contract documentsare used.

6.3 Inspection of WPS Qualification and Equipment

6.3.1 Prior to the use of a WPS in production welding,the Inspector shall make certain that the WPS is qualifiedin conformance with Clause 5 of this code, that eachwelding operation is covered by a written WPS, and thatsuch WPSs are available to the welders and Inspectorsfor reference.

6.3.2 The Inspector shall inspect the welding and cuttingequipment to be used in the work to verify that it con-forms to the requirements of 3.1.2.

6.4 Inspection of Welder, Welding Operator, and Tack Welder Qualifications

6.4.1 The Inspector shall allow welding to be performedonly by welders, welding operators, and tack welderswho are qualified in conformance with the requirementsof Clause 5, and shall verify that their qualificationsauthorize them to use the WPSs specified for the work,or shall make certain that each welder, welding operator,or tack welder has previously demonstrated such qualifi-cation under supervision acceptable to the Engineer.

6.4.2 When the quality of work by a welder, weldingoperator, or tack welder appears to be below the require-ments of this code, the Inspector may require that thewelder, welding operator, or tack welder demonstrate anability to produce sound welds by means of a simple test,such as the fillet weld break test, or by requiring com-plete requalification in conformance with Clause 5.

6.4.3 The Inspector shall require requalification of anywelder, welding operator, or tack welder whose qualifi-cation is not current by the requirements of this code.

6.4.4 When qualifying welders, welding operators, andtack welders, the Inspector shall observe the qualifica-tion tests.

6.5 Inspection of Work and Records6.5.1 The Inspector shall make certain that the size,length, and location of all welds conform to the require-

PART A

AASHTO/AWS D1.5M/D1.5:2008 CLAUSE 6. INSPECTION

135

ments of this code and to the detail drawings and that nounspecified welds have been added without approval.

6.5.2 The Inspector shall make certain only WPSs areemployed which meet the provisions of Clause 5.

6.5.3 The Inspector shall make certain that electrodes areused only in the positions and with the type of weldingcurrent and polarity for which they are classified.

6.5.4 The Inspector shall, at suitable intervals, observethe joint preparation, assembly practice, welding tech-niques, and performance of each welder, welding opera-tor, and tack welder to make certain that applicablerequirements of this code are met. The Inspector shallexamine the work to make certain that it meets therequirements of Clause 3 and 6.26. The size and contourof welds shall be measured using suitable gages. Visualinspection for cracks in welds and base metal, and forother discontinuities should be aided by strong lightmagnifiers, or such other devices as may be helpful.Acceptance criteria different from those described in thiscode may be used when approved by the Engineer.

6.5.5 The Inspector shall identify with a distinguishingmark or adequate document control as approved by theEngineer all parts or joints that the Inspector hasinspected and approved.

6.5.6 The Inspector shall keep a record of qualificationsof all welders, welding operators, and tack welders; allWPS qualifications or other tests that are made; the con-trol of welding materials and equipment; and such otherinformation as may be required.

6.5.7 For NDT, the Inspector shall ascertain that equip-ment, procedures, and techniques are in conformancewith 6.7. The QA Inspector may view the making ofNDT, examine and evaluate the test results, approve sat-isfactory welds, or reject unsatisfactory welds, approvesatisfactory methods proposed by the Contractor forrepairing unacceptable welds, and inspect the prepara-tion and rewelding of unacceptable welds.

6.5.8 The Inspector shall record the locations ofinspected areas and the findings of all NDT, togetherwith detailed descriptions of all repairs made.

6.6 Obligations of the Contractor6.6.1 The Contractor shall allow access to the projectfabrication facility by QA personnel. The Contractorshall cooperate with QA personnel and provide readyaccess to QC inspection records.

6.6.2 The Contractor shall be responsible for visualinspection and NDT described in 6.7 and necessary cor-

rection of all deficiencies in materials and workmanshipin conformance with the requirements of Clause 3 and6.26 and as specified elsewhere in contract documents.

6.6.3 The Contractor shall comply with all requests ofthe QA Inspector to correct deficiencies in materials andworkmanship, as specified in the contract documents.

6.6.4 In the event that faulty welding or its removal forrewelding damages the base metal so that in the judg-ment of the Engineer, its retention is not in conformancewith the intent of the contract documents, the Contractorshall remove and replace the damaged base metal or shallcompensate for the deficiency in a manner approved bythe Engineer.

6.6.5 If NDT, not specified in the original contract agree-ment, is subsequently requested by the Engineer, theContractor shall perform any requested testing or shallallow any requested testing to be performed. Costs shallbe negotiated by the Owner and the Contractor. Respon-sibility for the cost of extra work shall lie with theOwner. However, if such testing should disclose anattempt to defraud or reveal gross nonconformance tothis code, repair work shall be done at the Contractor’sexpense.

6.6.6 The Contractor shall schedule NDT to facilitateattendance by the QA Inspector. The QA Inspector shallbe advised by the Contractor of operational and NDTschedules and scheduled changes.

6.7 Nondestructive Testing (NDT)NDT in addition to visual inspection shall be performedby the Contractor to comply with this specification. Test-ing of base metals in conformance with 3.2; preparationof base metal; production welds; weld repairs; WPSqualification test weldments; and welder, welding opera-tor, and tack welder qualification test weldments shall beincluded. Costs of this NDT shall be considered inciden-tal to the structural steel fabrication or erection or both,and no separate payment shall be made.

6.7.1 CJP groove welds in main members shall be QCtested by NDT. Unless otherwise provided, RT shall beused for examination of CJP groove welds in butt jointssubject to calculated tension or reversal of stress. All CJPgroove welds in T- and corner joints shall be tested byUT. When required, testing of CJP groove welds in buttjoints in compression or shear may be done by RT or UT.

6.7.1.1 Welds made by either the ESW or EGW pro-cesses shall be tested by both RT and UT.

6.7.1.2 RT or UT of welds shall be performed in con-formance with the following frequency requirements:

PART A


136

(1) 100% of each joint subject to calculated tensionor reversal of stress, except on welds in vertical buttjoints in beams or girder webs, as follows:

(a) 1/6 of the web depth beginning at the point, orpoints, of maximum tension, and

(b) 25% of the remainder of the web depth needbe tested.

(c) If unacceptable discontinuities are found in (a)or (b) above the remainder of the weld shall be tested.

(2) 25% of each joint subject to compression orshear, or, at the Contractor’s option, 25% of the totaljoints subject to compression or shear. When the latter isselected, the tested joints shall be distributed throughoutthe work and shall total at least 25% of the compressionor shear weld length.

(a) If unacceptable discontinuities are found inspot testing, the entire length shall be tested.

(b) If unacceptable discontinuities are found in20% or more of the compression or shear joints in a“lot,” all compression and shear joints in that “lot” shallbe tested for their full length.

(c) A lot is defined as those tension or com-pression/shear joints, or both, which were welded inconformance with the same approved WPS and testedwith NDT as a group.

(d) Unless otherwise specified in the contract doc-uments, the above requirements do not apply to longitu-dinal butt joints in beam or girder webs. These weldsshall be subject to the inspection criteria of 6.7.2.

(3) The requirements for RT and UT shall applyequally to shop and field welds.

6.7.2 Unless otherwise specified, fillet welds and PJPgroove welds joining primary components of main mem-bers shall be QC tested using MT in conformance withthe following:

6.7.2.1 At least 300 mm [12 in] shall be tested inevery 3 m [10 ft] length including longitudinal welds inbutt joints in beam or girder webs, and 300 mm [12 in] ofsuch welds less than 3 m [10 ft] in length of each size ofweld and type of joint in main members including theend connections for such members. Typical welds whichrequire testing are web to flange, diaphragm connectionplates to web or flange; diaphragm sealing plate or gus-sets to web or flange in box members; cross frame anddiaphragm welds on curved bridges, etc. If unacceptablediscontinuities are found in any test length of weld, thefull length of the weld, or 1.5 m [5 ft] on both sides of thetest length, whichever is less, shall be tested.

6.7.2.2 For Grade 690/690W [100/100W] steels, allmain member fillet and PJP groove welds shall be testedfull-length by MT.

6.7.2.3 MT of fillet welds shall not be required forsecondary members.

6.7.3 After repairs of discontinuities have been made,additional NDT inspection shall be performed to ensurethat the repairs are satisfactory. This testing shall includethe repaired area plus at least 50 mm [2 in] on each sideof the repaired area.

6.7.4 Welds tested with NDT that do not meet therequirements of this code shall be repaired by the methodsof 3.7.

6.7.5 When RT is used, the procedure and techniqueshall be in conformance with Part B of this section.

6.7.6 When MT is used, the procedure and techniquesshall be in conformance with the dry powder MT ofwelds using the prod method or the yoke method.

6.7.6.1 The prod method shall be performed in con-formance with ASTM E 709, Guide for Magnetic Parti-cle Inspection, and the standards of acceptance shall bein conformance with 6.26.

(1) When the prod method is used to test steels with aminimum specified yield strength of 345 MPa [50 ksi] orgreater, aluminum prods shall be used on the test equip-ment. Copper prods shall not be used on such steels.

(2) Arcing shall be minimized by following theproper testing procedures.

6.7.6.2 The yoke method shall be performed in con-formance with ASTM E 709, and the standard of accep-tance shall be in conformance with 6.26.

(1) Testing by the yoke method shall be performedusing half-wave rectified DC or AC.

(2) Electromagnetic yokes shall have lifting forcesconforming to the following requirements:

6.7.6.3 Prior to MT, the surface shall be examined,and any adjacent area within at least 25 mm [1 in] of thesurface to be tested, shall be dry and free of contaminants

Current Type

Yoke Pole Leg Spacing (YPS), mm [in]

50 ≤ YPS < 100[2 ≤ YPS < 4]

100 ≤ YPS ≤ 150[4 ≤ YPS ≤ 6]

AC 45 N [10 lb] Not Applicable

DC 135 N [30 lb] 225 N [50 lb]

PART A


137

such as oil, grease, loose rust, loose sand, loose scale,lint, thick paint, welding flux, and weld spatter. Thinnonconductive coatings such as paint in the order of0.02 mm to 0.05 mm [1 mil to 2 mils] that do not inter-fere with the formation of indications may remain, butthey must be removed at all points where electrical con-tact is to be made.

Cleaning may be accomplished by detergents, organic sol-vents, descaling solutions, paint removers, vapor degreas-ing, sand or grit blasting, and ultrasonic cleaning methods.

6.7.6.4 The prod or poles shall be oriented in twodirections approximately 90° apart at each inspection point,to detect both longitudinal and transverse discontinuities.The prod or pole position shall overlap as testing progressesto ensure 100% inspection of the areas to be tested.

6.7.6.5 A report of MT shall be prepared and fur-nished to the Engineer.

(1) The report shall include the following minimuminformation:

(a) Part identification

(b) Examination procedure number (if applicable)

(c) Date of examination

(d) Technician’s name, certification level, andsignature

(e) Name and signature of Contractor’s or Owner’sInspectors, or both, who witnessed the examination

(f) Examination results

(g) Equipment make and model

(h) Yoke or prod spacing used

(i) Particles (manufacturer’s name) and color

(2) One copy shall be furnished to the Contractor forthe Owner.

6.7.7 For detecting discontinuities that are open to thesurface, PT may be used. The standard methods set forthin ASTM E 165 shall be used for PT, and the standardsof acceptance shall be in conformance with 6.26.

Part BRadiographic Testing (RT)

of Groove Welds in Butt Joints

6.8 Extent of TestingThe provisions of 6.7 shall identify the minimum extentof RT.

6.9 General6.9.1 The procedures and standards set forth in Part Bgovern radiographic testing of welds. The requirementsdescribed herein are specifically for testing groove weldsin butt joints in plate, shapes, and bars by X-ray orgamma ray sources. The methodology shall conform toASTM E 94, Guide for Radiographic Testing; ASTME 142, Method for Controlling Quality of RadiographicTesting; ASTM E 747, Practice for Design, Manufac-ture, and Material Grouping Classification of WireImage Quality Indicators (IQI) Used for Radiology; andASTM E 1032, Test Method for Radiographic Examina-tion of Weldments.

6.9.2 Variations in testing procedures, equipment, andacceptance standards may be used upon agreementbetween the Contractor and the Engineer. Such varia-tions include, but are not limited to, the following:

(1) RT of fillet, T-, and corner welds

(2) Changes in source-to-film distance

(3) Unusual application of film

(4) Unusual Image Quality Indicator applications(including film side IQIs)

(5) RT of thicknesses greater than 150 mm [6 in]

(6) Film types, densities, and variations in exposure,development, and viewing techniques

6.10 RT Procedure6.10.1 Radiographs shall be made using a single sourceof either X- or gamma radiation. The RT sensitivity shallbe judged based on hole-type IQI image or wire imagequality indicators (IQI). RT technique and equipmentshall provide sufficient sensitivity to clearly delineate therequired IQIs and the essential holes or wire sizes asdescribed in 6.10.7, Tables 6.1 and 6.1A, and Figures6.1E and 6.1F. Identifying letters and numbers shallshow clearly in the radiograph. For more detailed infor-mation see ASTM E 747.

6.10.2 RT shall be performed in conformance with allapplicable safety requirements.

6.10.3 When the contract documents require the removalof weld reinforcement, the welds shall be prepared forradiography by grinding as described in 3.6.3. Otherweld surfaces need not be ground or otherwise smoothedfor purposes of RT unless surface irregularities or thejunction between weld and base metal may causeunacceptable weld discontinuities to be obscured in theradiograph.

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6.10.3.1 Weld tabs (extension bars and run-off plates)shall be removed prior to RT, unless otherwise approvedby the Engineer.

6.10.3.2 When required by 3.13 or other provisions ofthe contract documents, steel backing shall be removedand the surface shall be finished flush by grinding priorto RT. Grinding shall be as described in 3.6.3.

6.10.3.3 When weld reinforcement or backing, orboth, are not removed and hole-type or wire IQI alternateplacement is not used, steel shims which extend at least3 mm [1/8 in] beyond three sides of the required hole-type or wire IQI shall be placed under the IQI so that thetotal thickness of steel between the IQI and the film isapproximately equal to the average thickness of the weldmeasured through its reinforcement and backing.

6.10.4 Radiographic film shall be ASTM System Class Ior II as described in ASTM E 1815. Lead foil screensshall be used as described in ASTM E 94. Fluorescentscreens shall be prohibited.

6.10.5 Radiographs shall be made with a single source ofradiation centered as near as practical with respect to thelength and width of that portion of the weld beingexamined.

6.10.5.1 Gamma ray sources, regardless of size, shallbe capable of meeting the geometric unsharpness limi-tation of ASME Boiler and Pressure Vessel Code,Section V, Article 2.

6.10.5.2 The source-to-subject distance shall not beless than the total length of film being exposed in a singleplane. This provision does not apply to panoramic expo-sures made under the provisions of 6.9.

6.10.5.3 The source-to-subject distance shall not beless than seven times the thickness of weld plus reinforce-ment and backing, if any, nor such that the inspectingradiation shall penetrate any portion of the weld repre-sented in the radiograph at an angle greater than 26-1/2°from a line normal to the weld surface.

6.10.6 X-ray units, 600 kV potential maximum, and Irid-ium 192 may be used as a source for all RT, providedthey have adequate penetrating ability. Cobalt 60 shall beused as an RT source only when the steel being radio-graphed exceeds 75 mm [3 in] in thickness. Other RTsources shall be subject to the approval of the Engineer.

6.10.7 Hole-type or wire IQIs shall show clearly on eachradiograph. The minimum number and their requiredlocations shall be as follows:

For welds joining nominally equal thicknesses, where aradiograph represents 250 mm [10 in] or greater of weldlength, two IQIs placed, as shown in Figure 6.1A; where

a radiograph represents less than 250 mm [10 in] ofweld, one hole-type or wire IQI placed as shown inFigure 6.1B.

For welds at a transition in thickness, where a radiographrepresents 250 mm [10 in] or greater of weld length, twohole-type or wire IQIs on the thinner plate and one hole-type or wire IQI on the thicker plate, or two wire IQIs atthe alternate wire IQI placement locations each as shownin Figure 6.1C; when a radiograph represents less than250 mm [10 in] of weld length, one hole-type or wire IQIon each plate or one wire IQI at the alternate wire IQIplacement location shown in Figure 6.1D.

6.10.7.1 Hole-type IQIs or wire IQI shall be placed onthe source side with hole-type IQI parallel to the weldjoint and holes at the outer edge of the area being radio-graphed. IQI wires shall be perpendicular to the jointwith the smallest wire on the outer edge of the area beingradiographed.

6.10.7.2 The thickness of hole-type IQIs or wire IQIset and the essential hole or wire shall be as described inTables 6.1 and 6.1A. A smaller essential hole or wire or athinner hole-type IQI, or a wire IQI using smaller wiresmay be selected by the Contractor, provided all otherprovisions for RT are met.

6.10.7.3 Thickness shall be measured as T1 or T2, orboth, at the locations shown in Figure 6.1A, 6.1B, 6.1C,or 6.1D and may be increased to provide for the thick-ness of allowable weld reinforcement, provided shimsare used as described in 6.10.3.3. Steel backing shall notbe considered part of the weld or reinforcement in hole-type IQI or wire IQI selection.

6.10.7.4 Hole-type IQIs shall be manufactured fromsteel, preferably stainless steel, and shall conform todimensions shown in Figure 6.1E. For more detailedinformation, see ASTM E 1025, Practice for Design,Manufacture, and Material Grouping Classification ofHole-Type Image Quality Indicators (IQI) Used forRadiography. Each IQI shall be manufactured with threeholes, one of which shall be of a diameter equal to twicethe IQI thickness (2T). The diameter of the two remain-ing holes shall be selected by the manufacturer. Theyshall ordinarily equal one time (1T) and four times (4T)the IQI thickness. IQI designations 10 through 25 shallcontain a 4T hole.

6.10.7.5 Wire IQIs shall be manufactured in conform-ance with Figure 6.1F. For more detailed information,see ASTM E 747.

6.10.8 Welded joints shall be radiographed and the filmindexed by methods that will provide complete and con-tinuous inspection of the joint within the limits specifiedto be examined. Joint limits shall show clearly in the

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radiographs. Short film, short screens, excessive under-cut by scattered radiation, or any other process thatobscures portions of the total weld length shall render theradiograph unacceptable.

6.10.8.1 Welds longer than 350 mm [14 in] may beradiographed by overlapping film cassettes and making asingle exposure, or by using single-film cassettes andmaking separate exposures. The provisions of 6.10.5shall apply.

6.10.8.2 To check for backscattered radiation, a leadsymbol “B,” 12.7 mm [1/2 in] high, and 1.6 mm [1/16 in]thick, shall be attached to the back of each film cassette.If the “B” image appears on the radiograph, the radio-graph shall be considered unacceptable.

6.10.9 Film widths shall be sufficient to depict all por-tions of the weld joint, including the HAZs, and shallprovide sufficient additional space for the required hole-type or wire IQIs and film identification without infring-ing upon the area of interest in the radiograph.

6.10.10 All radiographs shall be free from mechanical,chemical, or other blemishes to such extent that blem-ishes cannot mask or be confused with the image of anydiscontinuity in the area of interest in the radiograph.

6.10.10.1 Such blemishes include, but are not limitedto the following:

(1) Fogging

(2) Processing defects such as streaks, water marks,or chemical stains

(3) Scratches, finger marks, crimps, dirtiness, staticmarks, smudges, or tears

6.10.10.2 Faulty techniques include the following:

(1) Loss of detail due to poor screen-to-film contact

(2) False indications due to defective screens or internalfaults

6.10.11 The transmitted film density through the radio-graphic image of the body of the required IQI(s) and thearea of interest shall be 1.8 minimum for single-filmviewing for radiographs made with an X-ray source and2.0 minimum for radiographs made with a gamma raysource. For composite viewing of double-film exposures,the minimum density shall be 2.6. Each radiograph of acomposite set shall have a minimum density of 1.3. Themaximum density shall be 4.0 for either single or com-posite viewing.

6.10.11.1 The density measured shall be H & D density(radiographic density).

NOTE: H & D (radiographic) density is a measure offilm blackening, expressed as:

D = log Io /I

where

D = H & D (radiographic) density

Io = light intensity on the film, and

I = light transmitted through the film

6.10.11.2 When weld transitions in thickness areradiographed and the ratio of the thickness of the thickersection to the thickness of the thinner section is 3 orgreater, radiographs should be exposed to produce sin-gle-film densities of 3.0 to 4.0 in the thinner section.When this is done, the minimum density requirements of6.10.11 shall be waived, unless otherwise provided in thecontract documents.

6.10.12 A radiograph identification mark and two loca-tion identification marks shall be placed on the steel ateach radiograph location. A corresponding radiographidentification mark and two location identificationmarks, all of which shall show in the radiograph, shall beproduced by placing lead numbers or letters, or both,over each of the identical identification and locationmarks made on the steel to provide a means for matchingthe developed radiograph to the weld. Additional identi-fication information may be preprinted no less than20 mm [3/4 in] from the edge of the weld or shall beproduced on the radiograph by placing lead figures onthe steel.

6.10.13 Information required to show on the radiographshall include the Owner’s contract identification, initialsof the radiographic inspection company, initials of thefabricator, the fabricator’s shop order number, the radio-graphic identification (erection) mark, the date, and theweld repair number, if applicable.

6.10.14 Edge Blocks. Edge blocks shall be used whenradiographing welds in butt joints greater than 12 mm[1/2 in] in thickness. The edge blocks shall have a lengthsufficient to extend beyond each side of the weld center-line for a minimum distance equal to the weld thickness,but no less than 50 mm [2 in], and shall have a thicknessequal to or greater than the thickness of the weld. Theminimum width of the edge blocks shall be equal to halfthe weld thickness, but no less than 25 mm [1 in]. Theedge blocks shall be centered on the weld with a snug fitagainst the plate being radiographed, allowing no morethan a 3 mm [1/8 in] gap. Edge blocks shall be made ofradiographically clean steel and the surface shall have afinish of ANSI 3 µm [125 µin] or smoother (see Figure6.2).

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6.11 Acceptability of WeldsWelds shown by RT to have discontinuities unacceptableper 6.26.2 shall be corrected in conformance with 3.7.

6.12 Examination, Report, and Disposition of Radiographs

6.12.1 The Contractor shall provide a suitable variableintensity illuminator (viewer) with spot review ormasked spot-review capability. The viewer shall incor-porate a means for adjusting the size of the spot underexamination. The viewer shall have sufficient capacity toproperly illuminate radiographs with an H & D densityof 4.0. Film review shall be done in an area of subduedlight.

6.12.2 Before a weld subject to RT by the Contractor forthe Engineer is accepted, all of its radiographs, includingany that show unacceptable quality prior to repair, and areport interpreting them, shall be submitted to the QAInspector.

6.12.3 A full set of radiographs for welds subject toradiographic testing by the Contractor for the Engineer,including any that show unacceptable quality prior torepair, shall be delivered to the Owner upon completionof the work. The Contractor’s obligation to retain radio-graphs shall cease: (1) upon delivery of this full set to theOwner, or (2) one full year after the completion of theContractor’s work, provided the Owner is given priorwritten notice.

Part CUltrasonic Testing (UT)

of Groove Welds

6.13 General6.13.1 The procedures and standards set forth in Part Cgovern the UT of groove welds and HAZ between thethicknesses of 8 mm and 200 mm [5/16 in and 8 in]inclusive, when such testing shall be required by 6.7.

6.13.2 Variations in testing procedure, equipment, andacceptance standards not included in Part C of Clause 6may be used upon agreement with the Engineer. Suchvariations include other thicknesses, weld geometries,transducer sizes, frequencies, couplant, coated surfaces,testing techniques, etc. Such approved variations shall berecorded in the contract records.

6.13.3 To detect possible piping porosity, RT is requiredto supplement UT of ESW and EGW.

6.13.4 These procedures are not intended to be employedfor the procurement testing of base metals. However,welding-related discontinuities (cracking, lamellar tear-ing, delaminations, etc.) in the adjacent base metal whichwould not be acceptable under the provisions of this codeshall be reported to the Engineer for disposition.

6.14 Extent of Testing6.14.1 The provisions of 6.7 shall identify the minimumextent of UT.

6.14.2 The UT operator shall, prior to making a UT ex-amination, be furnished or have access to relevant infor-mation regarding weld-joint geometry, material thickness,and welding processes used in making the weldment.Any subsequent record of repairs made to the weldmentshall also be made available to the UT operator.

6.15 UT Equipment6.15.1 The UT instrument shall be the pulse echo typesuitable for use with transducers oscillating at frequen-cies between 1 megahertz (MHz) and 6 MHz. The dis-play shall be an “A” scan rectified video trace.

6.15.2 The horizontal linearity of the test instrumentshall be qualified over the full sound-path distance to beused in testing in conformance with 6.22.1 (see 6.17.1).

6.15.3 Test instruments shall be internally stabilized sothat after warm-up, no variation in response greater than1 dB occurs with a supply voltage change of 15% nomi-nal or, in the case of a battery, within the charge operat-ing life. There shall be an alarm or meter to signal a dropin battery voltage prior to instrument shutoff due to bat-tery exhaustion.

6.15.4 The test instrument shall have a calibrated gaincontrol (attenuator) adjustable in discrete 1 dB or 2 dBsteps over a range of at least 60 dB. The accuracy of thegain control (attenuator) settings shall be within plus orminus 1 dB. The procedure for qualification shall be asdescribed in 6.17.2 and 6.22.2.

6.15.5 The dynamic range of the instrument’s displayshall be such that a difference of 1 dB of amplitude canbe easily detected on the display.

6.15.6 Straight beam (longitudinal wave) search unittransducers shall have an active area of not less than300 square millimeters [1/2 square inches] nor morethan 650 square millimeters [1 square inches]. The trans-

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ducer shall be round or square. Transducer frequencyshall be 2 MHz to 2.5 MHz. Transducers shall be capa-ble of resolving the three reflections as described in6.21.1.3.

6.15.7 Angle beam search units shall consist of a trans-ducer and an angle wedge. The unit may be comprised ofthe two separate elements or may be an integral unit.

6.15.7.1 The transducer frequency shall be between2 MHz and 2.5 MHz, inclusive.

6.15.7.2 The transducer crystal shall be square orrectangular in shape and may vary from 15 mm to 25 mm[5/8 in to 1 in] in width and from 15 mm to 20 mm [5/8 into 3/4 in] in height (see Figure 6.3). The maximum ratioof width to height shall be 1.2 to 1.0, and the minimumratio 1.0 to 1.0.

6.15.7.3 The search unit shall produce a sound beamin the material being tested within plus or minus 2° ofone of the following proper angles: 70°, 60°, or 45°, asdescribed in 6.21.2.2.

6.15.7.4 Each search unit shall be marked to clearlyindicate the frequency of the transducer, nominal angleof refraction, and index point. The index point locationprocedure is described in 6.21.2.1.

6.15.7.5 Maximum allowable internal reflectionsfrom the search unit shall be as described in 6.17.4.

6.15.7.6 The dimensions of the search unit shall besuch that the distance from the leading edge of the searchunit to the index point shall not exceed 25 mm [1 in] (seeFigure 6.4).

6.16 Reference Standards6.16.1 The International Institute of Welding (IIW) ultra-sonic reference block, shown in Figure 6.5A, shall be thestandard used for both distance and sensitivity calibra-tion. Other portable blocks may be used, provided thereference level sensitivity for the instrument/search unitcombination is adjusted to be equivalent to that achievedwith the IIW Block (see Annex F, Part A, for examples).Other approved designs are shown in Figure 6.5B.

6.16.2 The use of a “corner” reflector for calibration pur-poses shall be prohibited.

6.16.3 The combination of search unit and instrumentshall resolve three holes in the RC resolution referencetest block shown in Figure 6.5B. The search unit positionshall be as described in 6.21.2.5. The resolution shall beevaluated with the instrument controls set at normal testsettings and with indications from the holes brought tomid-screen height. Resolution shall be sufficient to dis-

tinguish at least the peaks of indications from the threeholes.

6.17 Equipment Qualification6.17.1 The horizontal linearity of the test instrumentshall be prequalified after each 40 hours of instrumentuse in each of the distance ranges over which the instru-ment will be used. The qualification procedure shall bein conformance with 6.22.1 (see Annex F, FA3 for alter-native method).

6.17.2 The instrument’s gain control (attenuator) shallmeet the requirements of 6.15.4 and shall be checked forcorrect calibration at periods not to exceed two monthintervals in conformance with 6.22.2. Alternative meth-ods may be used for calibrated gain control (attenuator)qualification if proven at least equivalent with 6.22.2.

6.17.3 Maximum internal reflections from each searchunit shall be verified at a maximum time interval of40 hours of instrument use, in conformance with 6.22.3.

6.17.4 With the use of an approved calibration block,each angle beam search unit shall be checked after eacheight hours of use to determine that the contact face isflat, that the sound entry point is correct, and that thebeam angle is within the allowed plus or minus 2° toler-ance in conformance with 6.21.2.1 and 6.21.2.2. Searchunits which do not meet these requirements shall be cor-rected or replaced.

6.18 Calibration for Testing6.18.1 All calibrations and tests shall be made with thereject (clipping or suppression) control turned off. Use ofthe reject (clipping or suppression) control may alter theamplitude linearity of the instrument and invalidate testresults.

6.18.2 Calibration for sensitivity and horizontal sweep(distance) shall be made by the UT operator just prior totesting and at the location of each weld.

6.18.3 Recalibration shall be made after a change ofoperators, after each 30 minute maximum time interval,or when the electrical circuitry is disturbed in any waywhich includes the following:

(1) Transducer change

(2) Battery change

(3) Electrical outlet change

(4) Coaxial cable change

(5) Power outage (failure)

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6.18.4 Calibration for straight-beam testing of base metalshall be made with the search unit applied to Face A ofthe base metal and performed as follows:

6.18.4.1 The horizontal sweep shall be adjusted fordistance calibration to present the equivalent of at leasttwo plate thicknesses on the display.

6.18.4.2 The sensitivity shall be adjusted at a locationfree of indications so that the first back reflection fromthe far side of the plate will be 50% to 75% of full screenheight.

6.18.5 Calibration for angle beam testing shall be per-formed as follows (see Annex F, FA2.4 for alternativemethod):

6.18.5.1 The horizontal sweep shall be adjusted torepresent the actual sound path distance by using the IIWblock or alternative blocks as specified in 6.16.1. Thedistance calibration shall be made using either the 125 mm[5 in] scale or 250 mm [10 in] scale on the CRT screen,whichever is appropriate, unless joint configuration orthickness prevents full examination of the weld at eitherof these settings, in which case, the distance calibrationshall be made using 400 mm [15 in] or 500 mm [20 in]scale as required. The search unit position is described in6.21.2.3. At least two indications other than the initialpulse shall also be used for this distance calibration,because of the built-in time delay between the transducerface and the face of the search unit.

6.18.5.2 Zero Reference Level. The zero referencelevel sensitivity used for flaw evaluation (“b” on theultrasonic test report, Annex F, Form F-4) is attained byadjusting the calibrated gain control (attenuator) of theflaw detector, meeting the requirements of 6.15, so that amaximized horizontal trace deflection [adjusted to hori-zontal reference line height with calibrated gain control(attenuator)] results on the display, in conformance with6.21.2.4.

See Annex F, Part B, Form F-4 for a sample UT reportform.

6.19 Testing Procedures

6.19.1 An “X” line for flaw location shall be marked onthe test face of the weldment in a direction parallel to theweld axis. The location distance perpendicular to theweld axis is based on the dimensional figures on thedetail drawing and usually falls on the centerline of buttjoint welds. It always falls on the near face of the con-necting member of T and corner joint welds (the faceopposite Face C).

6.19.2 A “Y” accompanied with a weld identificationnumber shall be clearly marked on the base metal adja-cent to each weld that is ultrasonically tested. This mark-ing is used for the following purposes:

(1) Weld identification

(2) Identification of Face A

(3) Distance measurements and direction (+ or –)from the X line

(4) Location measurement from weld ends or edges

6.19.3 All surfaces to which a search unit is applied shallbe free of weld spatter, dirt, grease, oil (other than thatused as a couplant), coatings, and loose scale and shallhave a contour allowing intimate coupling.

6.19.4 A couplant material shall be used between thesearch unit and the test material. The couplant shall beeither glycerin or a cellulose gum and water mixture of asuitable consistency. A wetting agent may be added ifneeded. Light machine oil may be used for couplant oncalibration blocks.

6.19.5 The entire base metal through which ultrasoundmust travel to test the weld shall be tested for laminarreflectors using a straight beam search unit conformingto the requirements of 6.15.6 and calibrated in conform-ance with 6.18.4. If any area of base metal exhibits totalloss of back reflection or an indication equal to or greaterthan the original back reflection height is located in aposition that will interfere with the normal weld scanningprocedure, its size, location, and depth from the A faceshall be determined and reported on the UT report, andan alternate weld scanning procedure shall be used.

6.19.5.1 The reflector size evaluation procedure shallbe in conformance with 6.23.1.

6.19.5.2 If part of a weld is inaccessible to testing inconformance with the requirements of Table 6.2, due tolaminar content recorded in conformance with 6.19.5,the testing shall be conducted using one or more of thefollowing alternative procedures as necessary to attainfull weld coverage:

(1) Grind the weld surface(s) flush.

(2) Test from Faces A and B.

(3) Use other search unit angles.

6.19.6 Welds shall be tested using an angle beam searchunit conforming to the requirements of 6.15.7 with theinstrument calibrated in conformance with 6.18.5 usingthe angles shown in Table 6.2. Following calibration andduring testing, the only instrument adjustment allowed isthe sensitivity-level adjustment with the calibrated gaincontrol (attenuator). The reject (clipping or suppression)

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control shall be turned off. Sensitivity shall be increasedfrom the reference level for weld scanning in conform-ance with the provisions of Tables 6.3 or 6.4, as applicable.

6.19.6.1 The testing angle and scanning procedureshall be in conformance with those shown in Table 6.2.

6.19.6.2 All butt joint welds shall be tested from eachside of the weld axis. Corner and T-joint welds shall beprimarily tested from one side of the weld axis only. Allwelds shall be tested using the applicable scanning pat-tern or patterns shown in Figure 6.7 as necessary todetect both longitudinal and transverse flaws. It isintended that, as a minimum, all welds be tested by pass-ing sound through the entire volume of the weld and theHAZ in two crossing directions, wherever practical.

6.19.6.3 When a discontinuity indication appears onthe screen, the maximum attainable indication from thediscontinuity shall be adjusted to produce a horizontalreference level trace deflection on the display. Thisadjustment shall be made with the calibrated gain controlor (attenuator), and the instrument reading in decibelsshall be used as the “Indication Level,” “a,” for calculat-ing the “Indication Rating,” “d,” as shown on the testreport (Annex F, Part B, Form F-4).

6.19.6.4 The “Attenuation Factor,” “c,” on the testreport shall be attained by subtracting 25 mm [1 in] fromthe sound path distance and multiplying the remainder by2. This factor shall be rounded out to the nearest dBvalue. Fractional values less than 1/2 dB shall be reducedto the lower dB level and those of 1/2 or greater increasedto the higher level.

6.19.6.5 The “Indication Rating,” “d,” in the UTReport, Annex F, Part B, Form F-4, represents thealgebraic difference in decibels between the indicationlevel and the reference level with correction for attenua-tion as indicated in the following expressions:

Instruments with gain in dB:

a – b – c = d

Instruments with attenuation in dB:

b – a – c = d

6.19.7 The length of flaws shall be determined in con-formance with the procedure in 6.23.2.

6.19.8 Each weld discontinuity shall be accepted orrejected on the basis of its indication rating and its lengthin conformance with Tables 6.3 or 6.4. Only those dis-continuities which are rejectable need be recorded on thetest report, except that for welds designated in the con-tract documents as being Fracture Critical, indicationratings which are up to and including 6 dB less critical

(higher) than acceptance levels shall be recorded on thetest report.

6.19.9 Each rejectable discontinuity shall be indicated onthe weld by a mark directly over the discontinuity for itsentire length. The depth from the surface and indicationrating shall be noted on nearby base metal.

6.19.9.1 Evaluation of retested areas of repaired weldsshall be tabulated on a new line on the report form. If theoriginal form is used, an R1, R2, etc., shall prefix theindication number, designating the number of repairshaving been made in that specific area.

6.19.9.2 If additional report forms are used, the Rnumber shall prefix the report number.

6.19.10 Welds found unacceptable by UT shall berepaired by the methods described in 3.7. Repaired areasshall be retested ultrasonically, with results tabulated onthe original form (if available) or additional report forms.

6.20 Preparation and Disposition of Reports

6.20.1 A report form which clearly identifies the workand the area of inspection shall be completed by the UTtechnician at the time of inspection. The report form forwelds that are acceptable need only contain sufficientinformation to identify the weld, the Inspector (signa-ture), and the acceptability of the weld. An example ofsuch a form is shown in Annex F, Part B, Form F-4.

6.20.2 Before a weld subject to UT shall be accepted, allreport forms pertaining to the weld, including any thatshow unacceptable quality prior to repair, shall be sub-mitted to the QA Inspector.

6.20.3 A full set of completed report forms of welds sub-ject to UT, including any that show unacceptable qualityprior to repair, shall be delivered to the Owner uponcompletion of the work. The Contractor’s obligation toretain UT reports shall cease (1) upon delivery of this fullset to the Owner or (2) one full year after completion ofthe Contractor’s work, provided that the Owner is givenprior written notice.

6.21 Calibration of the UT UnitWith IIW or Other Approved Reference Blocks

See 6.16 and Figures 6.5A, 6.5B, and 6.6.

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6.21.1 Longitudinal Mode

6.21.1.1 The distance calibration procedure shall be asfollows: (see Annex F, FA1 for alternative method):

(1) Set the transducer in position G on the IIW block.

(2) Adjust instrument to produce indications at 25 mm[1 in], 50 mm [2 in], 75 mm [3 in], 100 mm [4 in], etc.,on the display.

6.21.1.2 The amplitude procedure shall be as follows(see Annex F, FA1.2 for alternative method):

(1) Set the transducer in position G on the IIW block.

(2) Adjust the gain until the maximized indicationfrom first back reflection attains 50% to 75% screenheight.

6.21.1.3 The resolution procedure shall be as follows:

(1) Set the transducer in position F on the IIW block.

(2) Transducer and instrument should resolve allthree distances.

6.21.1.4 Horizontal linearity qualification proceduresshall be in conformance with 6.17.1.

6.21.1.5 The gain control (attenuator) qualificationshall be as follows:

(1) Set the transducer in position T on DS block.

(2) Move the transducer toward position U perinstructions in 6.17.2 (see 6.17.2.1).

6.21.2 Shear Wave Mode (Transverse)

6.21.2.1 Locate or check the transducer sound entrypoint (index point) by the following procedure:

(1) Set the transducer in position D on the IIW block.

(2) Move the transducer until the signal from theradius is maximized. The point on the transducer whichaligns with the radius line on the calibration block is thepoint of sound entry (see Annex F, FA2.1 for alternativemethod).

6.21.2.2 Check or determine the transducer sound-path angle by one of the following procedures:

(1) Set the transducer in position B on IIW block forangles 40° through 60°, or in position C on IIW block forangles 60° through 70° (see Figure 6.6).

(2) For the selected angle, move the transducer backand forth over the line indicative of the transducer angleuntil the signal from the radius is maximized. Comparethe sound entry point on the transducer with the anglemark on the calibration block (tolerance ±2°) (see AnnexF, FA2.2 for alternative methods).

6.21.2.3 The distance calibration procedure shall be asfollows:

(1) Set the transducer in position D on the IIW block(any angle).

(2) Adjust the instrument to attain indications at100 mm [4 in] and 200 mm [8 in] or 225 mm [9 in] onthe display; 100 mm [4 in] and 225 mm [9 in] on Type 1block; or 100 mm [4 in] and 200 mm [8 in] on a Type 2block (see Annex F for alternate methods using the DSCor DC block).

6.21.2.4 The amplitude or sensitivity calibration pro-cedure shall be as follows:

(1) Set the transducer in position A on the IIW block(any angle);

(2) Adjust the maximized signal from the 1.5 mm[0.06 in] hole to attain a horizontal reference-line heightindication (see Annex F, FA2.4 for alternative method).

(3) The maximum decibel reading obtained shall beused as the “Reference Level,” “b” reading on the TestReport sheet (Annex F, Part B, Form F-4) per 6.16.1.

6.21.2.5 The resolution procedure is as follows:

(1) Set the transducer on resolution block RC posi-tion Q for 70° angle, position R for 60° angle, or positionS for 45° angle.

(2) Resolve the three test holes, at least to the extentof distinguishing the peaks of the indications from thethree holes, by the transducer and instrument.

6.22 Equipment Qualification Procedures

6.22.1 Horizontal Linearity Procedure. The followingprocedure shall be used for instrument qualification (seeAnnex F, FA3, for alternative method).

(1) Couple a straight-beam search unit meeting therequirements of 6.15.6 to the IIW or DS block in PositionG, T, or U (see Figure 6.6) as necessary to attain 5 backreflections in the qualification range being certified (seeFigure 6.6).

(2) Adjust the first and fifth back reflections to theirproper locations with use of the distance calibration andzero delay adjustments.

(3) Each indication shall be adjusted to referencelevel with the gain or attenuation control for horizontal-location examination.

(4) Each intermediate trace deflection location shallbe correct within ±2% of the screen width.

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145

6.22.2 Decibel dB Accuracy Procedure. In order toattain the accuracy (±1%) in reading the indicationheight, the display must be graduated vertically at 2%intervals or 2.5% for instruments with digital amplitudereadout at horizontal midscreen height. These gradua-tions shall be placed on the display between 60% and100% of screen height. This may be accomplished withuse of a graduated transparent screen overlay. If thisoverlay is applied as a permanent part of the UT unit,care should be taken that the overlay does not obscurenormal testing displays.

(1) Couple a straight-beam search unit, meeting therequirements of 6.15.6, to the DS block shown in Figure6.5B and position “T,” Figure 6.6 (see 6.17.2.1).

(2) Adjust the distance calibration so that the first50 mm [2 in] back reflection indication (hereafter called“the indication”) is at horizontal midscreen.

(3) Adjust the calibrated gain or attenuation controlso that the indication is exactly at or slightly above 40%screen height.

(4) Move the search unit toward position U (see Fig-ure 6.6), until the indication is at exactly 40% screenheight.

(5) Increase the sound amplitude 6 dB with the cali-brated gain or attenuation control. The indication leveltheoretically should be exactly at 80% screen height.

(6) Record the dB reading under “a” and actual per-cent screen height under “b” from step 5 on the certifica-tion report (Annex F, Part B, Form F-1), line 1.

(7) Move the search unit further toward position U,Figure 6.6, until the indication is at exactly 40% screenheight.

(8) Repeat step 5.

(9) Repeat step 6; except, information should beapplied to the next consecutive line on Annex F, Part B,Form F-1.

(10) Repeat steps 7, 8, and 9 consecutively until thefull range of the gain control (attenuator) is reached(60 dB minimum).

(11) Apply the information from columns “a” and “b”to equation 6.22.2.2 or the nomograph described in6.22.2.3 to calculate the corrected dB.

(12) Apply corrected dB from step 11 to column “c.”

(13) Subtract Column “c” value from Column “a”value and apply the difference in Column “d,” dB error.

(14) Information shall be tabulated on a form, includ-ing minimum equivalent information as displayed on

Form F-1, and the unit evaluated in conformance withinstructions shown on that form. These values may beeither positive or negative and shall be so noted.

(15) Form F-2 provides a relatively simple means ofevaluating data from item.

(16) Instructions for this evaluation are given in (16)through (18).

(17) Apply the dB information from column “e”(Form F-1) vertically and dB reading from column “a”(Form F-1) horizontally as X and Y coordinates for plot-ting a dB curve on Form F-2.

(18) The longest horizontal length, as represented bythe dB reading difference, which can be inscribed in arectangle representing 2 dB in height, denotes the dBrange in which the equipment meets the code require-ments. The minimum allowable range shall be 60 dB.

(19) Equipment that does not meet this minimumrequirement may be used, provided correction factors aredeveloped and used for flaw evaluation outside theinstrument acceptable linearity range, or the weld testingand flaw evaluation are kept within the acceptable verti-cal linearity range of the equipment. The dB error figures(Column “d”) may be used as correction factor figures.

6.22.2.1 The decibel calculating equation is as follows:

(1) dB2 – dB1 = 20 × Log (%2/%1)

or

dB2 = 20 × Log (%2/%1) + dB1

(2) As related to Annex F, Part B, Form F-1:

dB1 = Column adB2 = Column c%1 = Column b%2 = Defined on Form F-1

6.22.2.2 For notes on the use of the nomograph, seeAnnex F, Part B; Form F-3:

(1) Columns a, b, c, d, and e are on certificationsheet, Annex F, Part B, Form F-1.

(2) The A, B, and C scales are on the nomograph,Annex F, Part B, Form F-3.

(3) The zero points on the C scale shall be prefixedby adding the necessary value to correspond with theinstrument settings, i.e., 0, 10, 20, 30, etc.

6.22.2.3 Procedures for using the nomograph shall beas follows:

(1) Extend a straight line between the decibel readingfrom Column “a” applied to the C scale and the corre-

PART C


146

sponding percentage from Column “b” applied to the Ascale.

(2) Use the point where the straight line from step 1crosses the pivot line B as a pivot point for a secondstraight line.

(3) Extend a second straight line from the averagepercentage point on the A scale through the pivot pointdeveloped in step 2 and on to the dB scale C.

(4) This point on the C scale is indicative of the cor-rected dB for use in Column “c.”

6.22.2.4 For an example of the use of the nomograph,see Annex F, Part B, Form F-3.

6.22.3 Procedure for internal reflections shall be asfollows:

(1) Calibrate the equipment in conformance with6.18.5.

(2) Remove the search unit from the calibration blockwithout changing any other equipment adjustments.

(3) Increase the calibrated gain or attenuation 20 dBmore sensitive than reference level.

(4) The screen area beyond 12 mm [1/2 in] soundpath and above reference level height shall be free of anyindication.

6.23 Flaw Size Evaluation Procedures6.23.1 Straight (Longitudinal) Beam Testing. The sizeof lamellar discontinuities will not always be easilydetermined, especially those that are smaller than thetransducer size. When the discontinuity is larger than thetransducer, a full loss of back reflection will occur and a6 dB loss of amplitude and measurement to the centerlineof the transducer is usually reliable for determining flawedges. However, the approximate size evaluation ofthose reflectors, which are smaller than the transducer,shall be made by beginning outside of the discontinuitywith equipment calibrated in conformance with 6.18.4and moving the transducer toward the area of discontinu-ity until an indication on the screen begins to form. Theleading edge of the search unit at this point is indicativeof the edge of the discontinuity.

6.23.2 Angle Beam (Shear) Testing. The following pro-cedure shall be used to determine the lengths of indica-tion which have db ratings more serious than for a ClassD indication. The length of such indications shall bedetermined by measuring the distance between the trans-ducer centerline locations where the indication ratingamplitude drops 50% (6 dB) below the rating for the

applicable flaw classification. This length shall berecorded under “discontinuity length” on the test report.When warranted by flaw amplitude, this procedure shallbe repeated to determine the length of Class A, B, and Cflaws.

6.24 Scanning PatternsSee Figure 6.7.

6.24.1 Longitudinal Discontinuities

6.24.1.1 Scanning Movement A. Rotation angle a =10°.

6.24.1.2 Scanning Movement B. Scanning distance bshall be such that the section of weld being tested iscovered.

6.24.1.3 Scanning Movement C. Progression dis-tance c shall be approximately one-half the transducerwidth. Movements A, B, and C shall be combined intoone scanning pattern.

6.24.2 Transverse Discontinuities

6.24.2.1 Use scanning pattern D (when welds areground flush).

6.24.2.2 Use scanning pattern E (when weld rein-forcement is not ground flush); Scanning angle e = 15°max. The scanning pattern shall be such that the fullweld section is covered.

6.24.3 ESW or EGW Welds (Additional ScanningPattern)—Scanning Pattern E. Search unit rotation anglee shall be between 45° and 60°. The scanning patternshall be such that the full weld section is covered.

6.25 Examples of dB Accuracy Certification

Annex F, Part B, shows examples of the use of FormsF-1, F-2, and F-3 for the solution to a typical applicationof 6.22.2.

Part DWeld Acceptance Criteria

6.26 Quality of Welds6.26.1 Visual Inspection. All welds shall be visuallyinspected. A weld shall be acceptable by visual inspec-tion if it conforms to the following requirements:

PARTS C & D


147

6.26.1.1 The weld shall have no cracks.

6.26.1.2 Thorough fusion shall exist between adjacentlayers of weld metal and between weld metal and basemetal.

6.26.1.3 All craters are to be filled to the full crosssection of the weld, except for the ends of intermittentfillet welds outside of their effective length when suchwelds are allowed in the design.

6.26.1.4 Weld profiles shall be in conformance with3.6.

6.26.1.5 In primary members, undercut shall be nomore than 0.25 mm [0.01 in] deep when the weld istransverse to tensile stress under any design loading con-dition. Undercut shall be no more than 1 mm [1/32 in]deep for all other cases.

6.26.1.6 The frequency of piping porosity in the sur-face of fillet welds shall not exceed one in 100 mm [4 in]or six in 1200 mm [4 ft] of weld length and the maximumdiameter shall not exceed 2.4 mm [3/32 in].

(1) A subsurface inspection for porosity shall be per-formed whenever piping porosity 2.4 mm [3/32 in] orlarger in diameter extends to the surface at intervals of300 mm [12 in] or less over a distance of 1200 mm[4 ft], or when the condition of electrodes, flux, basemetal, or the presence of weld cracking indicates thatthere may be a problem with piping or gross porosity.

(2) This subsurface inspection shall be a visualinspection of 300 mm [12 in] exposed lengths of the filletweld throat after it has been ground or removed by aircarbon arc gouging to a depth of 1/2 the design throat.When viewed at mid-throat of the weld, the sum of thediameters of all porosity shall not exceed 10 mm [3/8 in]in any 25 mm [1 in] length of weld or 20 mm [3/4 in] inany 300 mm [12 in] length of weld.

6.26.1.7 A fillet weld in any single continuous weldmay underrun the nominal fillet weld size specified by2 mm [1/16 in] without correction, provided that theundersize portion of the weld does not exceed 10% of thelength of the weld. On the web-to-flange welds on gird-ers, underrun shall be prohibited at the ends for a lengthequal to twice the width of the flange.

6.26.1.8 CJP groove welds in butt joints transverse tothe direction of computed tensile stress shall have nopiping porosity. For all other groove welds, the fre-quency of piping porosity shall not exceed one in 100 mm[4 in] of length, and the maximum diameter shall notexceed 2.4 mm [3/32 in].

6.26.1.9 Visual inspection of welds in all steels maybegin immediately after the completed welds have

cooled to ambient temperature. Acceptance criteria forM270M [M270] Grades 690/690W [100/100W] (A 709M[A 709] Grades 690/690W [100/100W]) steels shall bebased on visual inspection performed not less than 48hours after completion of the weld.

6.26.2 RT and MT Inspection. Welds that are subject toRT or MT in addition to visual inspection shall have nocracks and shall be unacceptable if the RT or MT showsany of the types of discontinuities described in 6.26.2.1,6.26.2.2, 6.26.2.3, or 6.26.2.4.

6.26.2.1 For welds subject to tensile stress under anycondition of loading, the greatest dimension of any poros-ity or fusion-type discontinuity that is 2 mm [1/16 in] orlarger in greatest dimension shall not exceed the size, B,indicated in Figure 6.8 for the effective throat or weldsize involved. The distance from any porosity or fusion-type discontinuity described above to another such dis-continuity, to an edge, or to the toe or root of any inter-secting flange-to-web weld shall be not less than theminimum clearance allowed, C, indicated in Figure 6.8for the size of discontinuity under examination.

6.26.2.2 For welds subject only to compressive stressand specifically indicated as such on the design draw-ings, the greatest dimension of porosity or a fusion-typediscontinuity that is 3 mm [1/8 in] or larger in greatestdimension shall not exceed the size, B, nor shall thespace between adjacent discontinuities be less than theminimum clearance allowed, C, indicated by Figure 6.9for the size of discontinuity under examination.

6.26.2.3 Independent of the requirements of 6.26.2.1and 6.26.2.2, discontinuities having a greatest dimensionof less than 2 mm [1/16 in] shall be unacceptable if thesum of their greatest dimensions exceeds 10 mm [3/8 in]in any 25 mm [1 in] length of weld.

6.26.2.4 The limitations given by Figures 6.8 and 6.9for 38 mm [1-1/2 in] weld size shall apply to all weldsizes greater than 38 mm [1-1/2 in].

6.26.2.5 Annex I illustrates the application of therequirements given in 6.26.2.1.

6.26.3 UT

6.26.3.1 Welds that are subject to UT in addition tovisual inspection shall be acceptable if they meet the fol-lowing requirements:

(1) Welds subject to tensile stress under any condi-tion of loading shall conform to the requirements ofTable 6.3.

(2) Welds subject to compressive stress shall con-form to the requirements of Table 6.4.

PART D


148

6.26.3.2 Ultrasonically tested welds are evaluated onthe basis of a discontinuity reflecting ultrasound in pro-portion to its effect on the integrity of the weld.

(1) Indications of discontinuities that remain on thescreen as the search unit is moved towards and awayfrom the discontinuity (scanning movement “b”) may beindicative of planar discontinuities with significant flawheight dimension.

(2) As the orientation of such discontinuities, relativeto the sound beam, deviates from the perpendicular, dBratings which do not allow direct, reliable evaluation ofthe welded joint integrity may result.

(3) When indications that exhibit these planar charac-teristics are present at scanning sensitivity, a moredetailed evaluation of the discontinuity by other meansmay be required (e.g., alternate UT techniques, RT,grinding, or gouging for visual inspection, etc.).

6.26.3.3 CJP groove web-to-flange welds shall con-form to the requirements of Table 6.4, and acceptance fordiscontinuities detected by scanning movements otherthan scanning pattern “E” (see 6.24.2.2) may be based ona weld thickness equal to the actual web thickness plus25 mm [1 in].

(1) Discontinuities detected by scanning pattern Eshall be evaluated to the criteria of 6.26.3.1 for the actualweb thickness.

(2) When such web-to-flange welds are subject tocalculated tensile stress normal to the weld axis, theyshall be so designated on design drawings and shall con-form to the requirements of Table 6.3.

6.26.4 PT. Welds that are subject to PT, in addition tovisual inspection, shall be evaluated on the basis of therequirements for visual inspection.

6.26.5 Timing of NDT

6.26.5.1 When welds are subject to NDT in conform-ance with 6.26.2, 6.26.3, and 6.26.4, the testing maybegin immediately after the completed welds havecooled to ambient temperature.

6.26.5.2 Acceptance of welds in M270M [M270]Grades 690/690W [100/100W] (A 709M [A 709] Grades690/690W [100/100W]) steels shall be based on NDTperformed not less than 48 hours after completion of thewelds.

PART D

149


Table 6.1Hole-Type IQI Requirements (see 6.10.7)

Nominal Material Thickness Range, mm [in]

Source Side

Designation Essential Hole

Up to 6 [1/4] incl.Over 6 to 10 [1/4 to 3/8]Over 10 to 12 [3/8 to 1/2]Over 12 to 16 [1/2 to 5/8]Over 16 to 20 [5/8 to 3/4]Over 20 to 22 [3/4 to 7/8]Over 22 to 25 [7/8 to 1]Over 25 to 32 [1 to 1-1/4]Over 32 to 38 [1-1/4 to 1-1/2]Over 38 to 50 [1-1/2 to 2]Over 50 to 60 [2 to 2-1/2]Over 60 to 80 [2-1/2 to 3]Over 80 to 100 [3 to 4]Over 100 to 150 [4 to 6]Over 150 to 200 [6 to 8]

101215151720202530354045506080

4T4T4T4T4T4T4T4T2T2T2T2T2T2T2T

Table 6.1AWire IQI Requirements (see 6.10.7)

Nominal Material Thickness Range, mm [in] Source Side Maximum Wire Diameter, mm [in]

Up to 6 [1/4] incl.Over 6 to 10 [1/4 to 3/8]Over 10 to 16 [3/8 to 5/8]Over 16 to 20 [5/8 to 3/4]Over 20 to 38 [3/4 to 1-1/2]Over 38 to 50 [1-1/2 to 2]Over 50 to 60 [2 to 2-1/2]Over 60 to 100 [2-1/2 to 4]Over 100 to 150 [4 to 6]Over 150 to 200 [6 to 8]

0.25 [0.010]0.33 [0.013]0.41 [0.016]0.51 [0.020]0.63 [0.025]0.81 [0.032]1.02 [0.040]1.27 [0.050]1.60 [0.063]2.54 [0.100]

150


Table 6.2Testing Angle (see 6.19.6)

Procedure Chart

Weld Type

Material Thickness, mm [in]

8 [5/16]to

38 [1-1/2]

>38 [1-1/2] to

45 [1-3/4]

>45 [1-3/4] to

60 [2-1/2]

>60 [2-1/2]to

90 [3-1/2]

>90 [3-1/2]to

110 [4-1/2]

>110 [4-1/2]to

130 [5]

>130 [5]to

160 [6-1/2]

>160 [6-1/2]to

180 [7]

>180 [7]>to

200 [8]

* * * * * * * * *

Butt 1 O 1 F1Gor4

F1Gor5

F6or7

F8or10

F9

or11

F12or13

F 12 F

T- 1 O 1ForXF

4ForXF

5ForXF

7ForXF

10ForXF

11ForXF

13ForXF

— —

Corner 1 O 1ForXF

1Gor4

ForXF

1Gor5

ForXF

6or7

ForXF

8or10

FofXF

9or11

ForXF

13or14

ForXF

— —

Electrogas and Electroslag

1 O 1 O1Gor4

1**1Gor3

P1orP3

6or7

P311or15

P311or15

P311or15

P311or

15**P3

Notes:1. Where possible, all examinations shall be made from Face A and in Leg 1, unless otherwise specified in this Table.2. Root areas of single groove weld joints which have backing strips not requiring removal by contract, shall be tested in Leg 1, where possible, with

Face A being that opposite the backing strip. (Grinding of the weld face or testing from additional weld faces may be necessary to allow completescanning of the weld root.)

3. Examination in Leg II or III shall be made only to satisfy provisions of this table or when necessary to test weld areas made inaccessible by anunground weld surface, or interference with other portions of the weldment, or to meet the requirements of 6.19.6.2.

4. A maximum of Leg III shall be used only where thickness or geometry prevents scanning of complete weld areas and HAZs in Leg I or Leg II.5. On tension welds on bridges, the top quarter of thickness shall be tested with the final leg of sound progressing from Face B toward Face A, the bot-

tom quarter of thickness shall be tested with the final leg of sound progressing from Face A toward Face B; i.e., the top quarter of thickness shall betested either from Face A in Leg II or from Face B in Leg I at the Contractor’s option, unless otherwise specified in the contract documents.

6. The weld face indicated shall be ground flush before using procedure 1G, 6, 8, 9, 12, 14, or 15. Face A for both connected members shall be in thesame plane.

(See Legend and Notes on next page)

151


Table 6.2 (Continued)Testing Angle (see 6.19.6)

Legend:X — Check from Face “C.”G — Grind weld face flush.O — Not required.A Face — the face of the material from which the initial scanning is done (on T- and corner joints, follow above

sketches).B Face — opposite the “A” face (same plate).C Face — the face opposite the weld on the connecting member or a T- or corner joint.* — Required only where display reference height indication of discontinuity shall be noted at the weld

metal-base metal interface while searching at scanning level with primary procedures selected from firstcolumn.

** — Use 400 mm [15 in] or 500 mm [20 in] screen distance calibration.P — Pitch and catch shall be conducted for further discontinuity evaluation in only the middle half of the

material thickness with only 45° or 70° transducers of equal specification, both facing the weld. (Trans-ducers shall be held in a fixture to control positioning—see sketch.) Amplitude calibration for pitch andcatch shall normally be made by calibrating a single search unit. When switching to dual search unitsfor pitch and catch inspection, there should be assurance that this calibration does not change as a resultof instrument variables.

F — Weld metal-base metal interface indications shall be further evaluated with either 70°, 60°, or 45° trans-ducer—whichever sound path is nearest to being perpendicular to the suspected fusion surface.

Procedure Legend

Area of Weld Thickness

No.Top

QuarterMiddle

HalfBottomQuarter

1 70° 70° 70°

2 60° 60° 60°

3 45° 45° 45°

4 60° 70° 70°

5 45° 70° 70°

6 70°G A 70° 60°

7 60° B 70° 60°

8 70°G A 60° 60°

9 70°G A 60° 45°

10 60° B 60° 60°

11 45° B 70°** 45°

12 70°G A 45° 70°G B

13 45° B 45° 45°

14 70°G A 45° 45°

15 70°G A 70°A B 70°G B

152


Table 6.3UT Acceptance-Rejection Criteria—Tensile Stress (see 6.26.3.1)

Weld Thicknessa (mm [in]) and Search Unit Angle

FlawSeverity Class

8 [5/16]through20 [3/4]

>20 [3/4] through

38 [1-1/2] >38 [1-1/2] through 60 [2-1/2] >60 [2-1/2] through 100 [4] >100 [4] through 200 [8]

70° 70° 70° 60° 45° 70° 60° 45° 70° 60° 45°

Class A+10 andlower

+8 andlower

+4 and lower

+7 and lower

+9 andlower

+1 and lower

+4 and lower

+6 andlower

–2 and lower

+1 and lower

+3 and lower

Class B+11 +9 +5

+6+8+9

+10+11

+2+3

+5+6

+7+8

–10

+2+3

+4+5

Class C+12 +10 +7

+8+10+11

+12+13

+4+5

+7+8

+9+10

+1+2

+4+5

+6+7

Class D+13

and up+11

and up+9

and up+12

and up+14

and up+6

and up+9

and up+11

and up+3

and up+6

and up+8

and up

a Weld thickness shall be defined as the nominal thickness of the thinner of the two parts being joined, given in mm [in].

Notes:1. Class B and C flaws shall be separated by at least 2L, L being the length of the longer flaw, except that when two or more such flaws are not sepa-

rated by at least 2L, but the combined length of flaws and their separation distance shall be equal to or less than the maximum allowable lengthunder the provisions of Class B or C, the flaw shall be considered a single acceptable flaw.

2. Class B and C flaws shall not begin at a distance less than 2L from the end of the weld, L being the flaw length.3. Flaws detected at “scanning level” in the root face area of CJP double groove weld joints shall be evaluated using an indicating rating 4 dB more

sensitive than described in 6.19.6.5 when such welds are designated as “tension welds” on the drawing (subtract 4 dB from the indication rating“d”).

4. For indications that remain on the display as the search unit is moved, see 6.26.3.2.

Class A (large flaws)Any indication in this category shall be rejected (regardless of length).

Class B (medium flaws)Any indication in this category having a length greater than 20 mm[3/4 in] shall be rejected.

Class C (small flaws)Any indication in this category having a length greater than 50 mm[2 in] in the middle half or 20 mm [3/4 in] length in the top or bottomquarter of the weld thickness shall be rejected.

Class D (minor flaws)Any indication in this category shall be accepted regardless of length orlocation in the weld.

Scanning Levels

Sound Path, mm [in]bAbove Zero

Reference, dB

through 60 [2-1/2]>60 [2-1/2] through 125 [5]>125 [5] through 250 [10]>250 [10] through 400 [15]

20253545

b This column refers to sound path distance; not material thickness.

153


Table 6.4UT Acceptance-Rejection Criteria—Compressive Stress (see 6.26.3.1)

Weld Thicknessa (mm [in]) and Search Unit Angle

FlawSeverity Class

8 [5/16] through20 [3/4]

>20 [3/4] through

38 [1-1/2] >38 [1-1/2] through 60 [2-1/2] >60 [2-1/2] through 100 [4] >100 [4] through 200 [8]

70° 70° 70° 60° 45° 70° 60° 45° 70° 60° 45°

Class A+5 andlower

+2 andlower

–2 and lower

+1 and lower

+3 andlower

–5 and lower

–2 and lower

0 andlower

–7 and lower

–4 and lower

–1 and lower

Class B+6 +3 –1

0+2+3

+4+5

–4–3

–10

+1+2

–6–5

–3–2

0+1

Class C+7 +4 +1

+2+4+5

+6+7

–2 to+2

+1+2

+3+4

–4 to+2

–1 to+2

+2+3

Class D+8

and up+5

and up+3

and up+6

and up+8

and up+3

and up+3

and up+5

and up+3

and up+3

and up+4

and up

a Weld thickness shall be defined as the nominal thickness of the thinner of the two parts being joined, given in mm [in].

Notes:1. Class B and C flaws shall be separated by at least 2L, L being the length of the longer flaw, except that when two or more such flaws are not sepa-

rated by at least 2L, but the combined length of flaws and their separation distance shall be equal to or less than the maximum allowable lengthunder the provisions of Class B or C, the flaw shall be considered a single acceptable flaw.

2. Class B and C flaws shall not begin at a distance less than 2L from weld ends carrying primary tensile stress, L being the flaw length.3. ESW or EGW welds: Flaws detected at “scanning level” which exceed 50 mm [2 in] in length shall be suspected as being piping porosity and shall

be further evaluated with RT.4. For indications that remain on the display as the search unit is moved, see 6.26.3.2.

Class A (large flaws)Any indication in this category shall be rejected (regardless of length).

Class B (medium flaws)Any indication in this category having a length greater than 20 mm[3/4 in] shall be rejected.

Class C (small flaws)Any indication in this category having a length greater than 50 mm[2 in] shall be rejected.

Class D (minor flaws)Any indication in this category shall be accepted regardless of length orlocation in the weld.

Scanning Levels

Sound Path, mm [in]bAbove Zero

Reference, dB

through 60 [2-1/2]>60 [2-1/2] through 125 [5]>125 [5] through 250 [10]>250 [10] through 400 [15]

14192939

b This column refers to sound path distance; not material thickness.

154


Figure 6.1A—Radiographic Identification and Hole-Type or Wire IQI Locations on Approximately Equal Thickness Joints 250 mm [10 in] and Greater in Length (see 6.10.7)

Figure 6.1B—Radiographic Identification and Hole-Type or Wire IQI Locations on Approximately Equal Thickness Joints Less Than 250 mm [10 in] in Length (see 6.10.7)

155


Figure 6.1C—Radiographic Identification and Hole-Type or Wire IQI Locations onTransition Joints 250 mm [10 in] and Greater in Length (see 6.10.7)

Figure 6.1D—Radiographic Identification and Hole-Type or Wire IQI Locations on Transition Joints Less Than 250 mm [10 in] in Length (see 6.10.7)

156


a IQIs No. 5 through 9 are not 1T, 2T, and 4T.

Note: Holes shall be true and normal to the IQI. Do not chamfer.

Figure 6.1E—Hole-Type IQI Design (see 6.10.7.4)(Reprinted by permission of the American Society for Testing and Materials, copyright.)

Table of Dimensions of IQI (in mm)

Number(Note a) A B C D E F

IQI Thickness and Hole Diameter

Tolerance

5–204–590–179

38.10 ± 0.3838.10 ± 0.3857.15 ± 0.80

19.05 ± 0.3819.05 ± 0.3834.92 ± 0.80

11.13 ± 0.3811.13 ± 0.3819.05 ± 0.80

6.35 ± 0.386.35 ± 0.389.52 ± 0.80

12.70 ± 0.3812.70 ± 0.3825.40 ± 0.80

6.35 ± 0.806.35 ± 0.809.52 ± 0.80

±0.013±0.06±0.13

Table of Dimensions of IQI (in in)

Number(Note a) A B C D E F

IQI Thickness and Hole Diameter

Tolerance

5–2021–5960–179

1.500 ± 0.0151.500 ± 0.0152.250 ± 0.030

0.750 ± 0.0150.750 ± 0.0151.375 ± 0.030

0.438 ± 0.0150.438 ± 0.0150.750 ± 0.030

0.250 ± 0.0150.250 ± 0.0150.375 ± 0.030

0.500 ± 0.0150.500 ± 0.0151.000 ± 0.030

0.250 ± 0.0300.250 ± 0.0300.375 ± 0.030

±0.0005±0.0025±0.0050

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Figure 6.1F—Wire-Type IQI (see 6.10.7.5)(Reprinted by permission of the American Society for Testing and Materials, copyright.)

Image Quality Indicator (Wire Penetrameter) Sizes

Wire Diameter, mm [in]

Set A Set B Set C Set D

0.08 [0.0032] 0.25 [0.010] 0.81 [0.032] 2.5 [0.10]0

0.10 [0.004]0 0.33 [0.013] 1.02 [0.040] 3.2 [0.126]

0.13 [0.005]0 00.4 0[0.016]0 1.27 [0.050] 4.06 [0.160]0

0.16 [0.0063] 0.51 [0.020] 1.60 [0.063] 5.1 [0.20]

0.2 0[0.008]0 0.64 [0.025] 2.03 [0.080] 6.4 [0.25]

0.25 [0.010]0 0.81 [0.032] 2.5 0[0.100] 8.00 [0.32]

158


a Transition may start beyond edge block.

Note: Edge block shall not be tack welded (see 6.10.14).

Figure 6.2—RT Edge Block Placement

159


Figure 6.3—Transducer Crystal(see 6.15.7.2)

Figure 6.4—Qualification Procedure of Search UnitUsing IIW Reference Block (see 6.15.7.6)

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Notes:1. The dimensional tolerance between all surfaces involved in referencing or calibrating shall be within ±0.13 mm [±0.005 in] of detailed

dimension.2. The surface finish of all surfaces to which sound shall be applied or reflected from shall have a maximum of 3 µm [125 µin].3. All material shall be M270M [A 709M] Gr. 250 [36] or acoustically equivalent.4. All holes shall have a smooth internal finish and shall be drilled at 90° to the material surface.5. Degree lines and identification markings shall be indented into the material surface so that permanent orientation can be maintained.6. Other approved reference blocks with slightly different dimensions or distance calibration slot features are allowed.7. These notes shall apply to all sketches in Figures 6.5A and 6.5B.

Figure 6.5A—International Institute of Welding (IIW) UT Reference Blocks (see 6.16.1)

161


Figure 6.5B—Other Approved UT Reference Blocks (see 6.16.1)[Dimensions in Millimeters]

162


Figure 6.5B (Continued)—Other Approved UT Reference Blocks (see 6.16.1)[Dimensions in Inches]

163


Figure 6.6—Transducer Positions (Typical) (see 6.21)

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Notes:1. Testing patterns are all symmetrical around the weld axis with the exception of pattern D which shall be conducted directly over the

weld axis.2. Testing from both sides of the weld axis shall be to be made wherever mechanically possible.

Figure 6.7—Plan View of UT Scanning Patterns (see 6.24)

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Note: Adjacent discontinuities, spaced less than the minimum spacing required, shall be measured as one length equal to the sum of thetotal length of the discontinuities plus the length of the space between them and evaluated as a single discontinuity.

Figure 6.8—Weld Quality Requirements for Discontinuities Occurring in Tension Welds (Limitations of Porosity and Fusion Discontinuities) (see 6.26.2.1)

166


a The maximum size of a discontinuity located within this distance from an edge of plate shall be 3 mm [1/8 in], but a 3 mm [1/8 in] discon-tinuity must be 6 mm [1/4 in] or more away from the edge. The sum of discontinuities less than 3 mm [1/8 in] in size and located within thisdistance from the edge shall not exceed 5 mm [3/16 in]. Discontinuities 2 mm [1/16 in] to less than 3 mm [1/8 in] shall not be restricted inother locations unless they are separated by less than 2 L (L being the length of the larger discontinuity); in which case, the discontinui-ties shall be measured as one length equal to the total length of the discontinuities and space and evaluated as shown in Figure 6.8.

Figure 6.9—Weld Requirements for Discontinuities Occurring in Compression Welds (Limitations of Porosity or Fusion Type Discontinuities) (see 6.26.2.2)


167

7.1 ScopeClause 7 contains general requirements for welding steelstuds to steel (see 7.2.7 and 1.2.2 for approved steels). Inaddition, it stipulates specific requirements for thefollowing:

(1) Workmanship, preproduction testing, operatorqualification, and application qualification testing, whenrequired, all to be performed by the Contractor

(2) QC and QA inspection of stud welding duringproduction

(3) Mechanical properties of steel studs, and require-ments for qualification of stud bases, all tests and docu-mentation to be furnished by the stud manufacturer

7.2 General Requirements7.2.1 Studs shall be of suitable design for arc welding tosteel members with the use of automatically timed studwelding equipment. The type and size of the stud shall beas specified by the drawings, specifications, or specialprovisions. For headed-type studs, see Figure 7.1.

7.2.2 An arc shield (ferrule) of heat-resistant ceramic orother suitable material shall be furnished with each stud.

7.2.3 A suitable deoxidizing and arc stabilizing flux forwelding shall be furnished with each stud of 8 mm [5/16 in]diameter or larger. Studs less than 8 mm [5/16 in] indiameter may be furnished with or without flux.

7.2.4 Only studs with qualified stud bases shall be used.A stud base, to be qualified, shall have passed the testdescribed in Annex E. The arc shield used in productionshall be the same as used in qualification tests or asrecommended by the manufacturer. Qualification of studbases in conformance with Annex E shall be at themanufacturer’s expense.

7.2.5 Finish shall be produced by heading, rolling, ormachining. Finished studs shall be of uniform qualityand condition, free of injurious laps, fins, seams, cracks,twists, bends, or other injurious discontinuities. Radialcracks or bursts in the head of a stud shall not be causefor rejection, provided that the cracks or bursts do notextend more than half the distance from the head periph-ery to the shank, as determined by visual inspection.

NOTE: Heads of shear connectors or anchor studs aresubject to cracks or bursts, which are names for the samething. Cracks or bursts designate an abrupt interruptionof the periphery of the stud head by radial separation ofthe metal. Such interruptions do not adversely affect thestructural strength, corrosion resistance, nor other func-tional requirements of headed studs.

7.2.6 Only bases qualified under Annex E shall be used.When requested by the Engineer, the Contractor shallprovide the following information:

(1) A description of the stud and arc shield

(2) Certification from the manufacturer that the studbase is qualified as described in 7.2.4

(3) Qualification test data

7.2.7 M270M [M270] Grades 690/690W [100/100W](A 709M [A 709] Grades 690/690W [100/100W]) steelsshall not be stud welded without approval of theEngineer.

7.3 Mechanical Requirements

7.3.1 Studs shall be made from cold-drawn bar stockconforming to the requirements of ASTM A 108, Speci-fication for Steel Bars, Carbon Cold Finished, StandardQuality Grades, Grades G10100 through G10200, inclu-sive, either semi-killed or killed deoxidation.

7. Stud Welding

CLAUSE 7. STUD WELDING AASHTO/AWS D1.5M/D1.5:2008

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7.3.1.1 Mechanical property requirements of studsother than outlined below shall be specified by theEngineer.

7.3.1.2 At the manufacturer’s option, mechanicalproperties of studs shall be determined by testing either(1) the steel after cold finishing, or (2) the full diameterfinished studs. In either case, the studs shall conform tothe requirements shown in Table 7.1.

7.3.2 Mechanical properties shall be determined in con-formance with the applicable sections of ASTM A 370,Test Methods and Definitions for Mechanical Testing ofSteel Products. A typical test fixture is used, similar tothat shown in Figure 7.2.

7.3.3 Upon request by the Engineer, the Contractor shallfurnish the following:

7.3.3.1 The Contractor shall provide the stud manu-facturer’s certification that the studs, as delivered, con-form to the applicable requirements of 7.2 and 7.3.

7.3.3.2 The Contractor shall provide certified copiesof the stud manufacturer’s test reports covering the lastcompleted set of in-plant quality control mechanicaltests, required by 7.3 for each stock size delivered. Thequality control test shall have been made within the sixmonth period before delivery of the studs.

7.3.4 When quality control tests are not available, theContractor shall furnish mechanical test reports conform-ing to the requirements of 7.3. The mechanical tests shallbe on finished studs provided by the manufacturer of thestuds. The number of tests to be performed shall be spec-ified by the Engineer.

7.3.5 The Engineer may select studs of each type andsize used under the contract as necessary for checkingthe requirements of 7.2 and 7.3. Furnishing these studsshall be at the Contractor’s expense. Testing shall be atthe Owner’s expense.

7.4 Workmanship7.4.1 At the time of welding, the studs shall be free fromrust, rust pits, scale, oil, moisture, and other deleteriousmatter that would adversely affect the welding operation.

7.4.2 The stud base shall not be painted, galvanized, norcadmium-plated prior to welding.

7.4.3 The areas to which the studs are to be welded shallbe free of scale, rust, moisture, and other injurious mate-rial to the extent necessary to obtain satisfactory welds.These areas may be cleaned by wire brushing, scaling,

prick-punching, or grinding. Extreme care should beexercised when welding through metal decking.

7.4.4 The arc shields or ferrules shall be kept dry. Anyarc shields which show signs of surface moisture fromdew or rain shall be oven dried at 120°C [250°F] for twohours before use.

7.4.5 Longitudinal and lateral spacings of stud shearconnectors (type B) with respect to each other and toedges of beam or girder flanges may vary a maximum of25 mm [1 in] from the location shown in the drawings.The clear distance between studs shall not be less than25 mm [1 in] unless approved by the Engineer. Theminimum distance from the edge of a stud base to the edgeof a flange shall be the diameter of the stud plus 3 mm[1/8 in] but preferably not less than 40 mm [1-1/2 in].

7.4.6 After welding, arc shields shall be broken free fromstuds to be embedded in concrete, and, where practical,from all other studs.

7.4.7 The studs, after welding, shall be free of any dis-continuities or substances that would interfere with theirintended function. However, nonfusion on the legs of theflash and small shrink fissures are acceptable. The filletweld profiles shown in Figure 3.3 do not apply to theflash of automatically timed stud welds. The expelledmetal around the base of the stud shall be designated asflash in conformance with Annex D of this code. It shallnot be defined as a fillet weld such as those formed byconventional arc welding. The stud weld flash may havenonfusion in its vertical leg and overlap on its horizontalleg, and it may contain occasional small shrink fissuresor other discontinuities that usually form at the top of theweld flash with essentially radial or longitudinal orienta-tion, or both, to the axis of the stud. Such nonfusion, onthe vertical leg of the flash, and small shrink fissuresshall be acceptable.

7.5 Technique7.5.1 Studs shall be welded with automatically timed studwelding equipment connected to a suitable source of di-rect current electrode negative (DCEN) power. Weldingvoltage, current, time, and gun settings for lift and plungeshould be set at optimum settings, based on past practice,recommendations of stud and equipment manufacturer,or both. AWS C5.4, Recommended Practices for StudWelding, should also be used for technique guidance.

7.5.2 If two or more stud welding guns are to be operatedfrom the same power source, they shall be interlocked sothat only one gun can operate at a time, and so that the

AASHTO/AWS D1.5M/D1.5:2008 CLAUSE 7. STUD WELDING

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power source has fully recovered from making one weldbefore another weld is started.

7.5.3 While in operation, the welding gun shall be held inposition without movement until the weld metal hassolidified.

7.5.4 Welding shall not be done when the base metaltemperature is below –20°C [0°F] or when the surface iswet or exposed to falling rain or snow.

7.5.4.1 When the temperature of the base metal isbelow 0°C [32°F], one additional stud in each 100 studswelded shall be tested by methods described in 7.7.1.3and 7.7.1.4, except that the angle of testing shall beapproximately 15°. This is in addition to the first twostuds tested for each start of a new production period orchange in setup.

7.5.4.2 Setup includes stud gun, power source, studdiameter, gun lift and plunge, total welding lead length,or changes greater than ±5% in current (amperage) andtime.

7.5.5 At the option of the Contractor, studs may be filletwelded by the SMAW, provided the following require-ments shall be met:

7.5.5.1 The minimum fillet size to be used shall be thelarger of those required in Table 2.1 or 7.2.

7.5.5.2 Welding shall be done with low-hydrogenelectrodes 4.0 mm [5/32 in] or 4.8 mm [3/16 in] in diam-eter except that a smaller diameter electrode may be usedon studs 10 mm [3/8 in] or less in diameter or for out-of-position welds.

7.5.5.3 The stud base shall be prepared so that thebase of the stud fits against the base metal.

7.5.5.4 All rust and mill scale at the location of thestud shall be removed from the base metal by grinding.The end of the stud shall also be clean.

7.5.5.5 The base metal to which studs are welded shallbe preheated in conformance with the requirements ofTable 4.4.

7.5.5.6 Fillet welded stud bases shall be visuallyinspected per 6.5.

7.6 Stud Application Qualification Requirements

7.6.1 Prequalification. Studs which are shop or fieldapplied in the flat (down-hand) position to a planarand horizontal surface shall be deemed prequalified byvirtue of the manufacturer’s stud-base qualification tests

(Annex E), and no further application testing is required.The limit of flat position is defined as 0°–15° slope onthe surface to which the stud is applied.

The following are some nonprequalified stud applica-tions that require tests of this section:

(1) Studs which are applied on nonplanar surfaces orto a planar surface in the vertical or overhead positions.

(2) Studs which are welded through decking. Thetests should be with material representative of the condi-tion to be used in construction.

(3) Studs welded to steels other than those describedin 1.2.2.

7.6.2 Responsibilities for Tests. The Contractor or studapplicator shall be responsible for the performance ofthese tests. Tests may be performed by the Contractor orstud applicator, the stud manufacturer, or by another test-ing agency satisfactory to all parties involved.

7.6.3 Preparation of Specimens

7.6.3.1 Test specimens shall be prepared by weldingthe studs being qualified to specimen plates of M270M[M270] Grade 250 [36] (A 709M [A 709] Grade 250[36]) steel or any base metal described in 1.2.2.

7.6.3.2 Weld position, nature of base metal and studsurfaces, current, and time shall be recorded.

7.6.4 Number of Specimens. Ten (10) specimens shallbe welded consecutively using recommended WPSs andsettings for each diameter, position, and surfacegeometry.

7.6.5 Tests Required. The ten (10) specimens shall betested using one or more of the following test methods:bending, torquing, or tensioning.

7.6.6 Test Methods

7.6.6.1 Bend Test. Studs shall be bend tested bybeing bent 90° from their original axis. A stud applica-tion shall be considered qualified if all the test specimensare bent 90° and fracture occurs in the plate or shapematerial or in the shank of the stud and not in the weld.

7.6.6.2 Torque Test. Studs shall be torque testedusing a torque-test arrangement that is substantially inconformance with Figure 7.3. A stud application shall beconsidered qualified if all test specimens are torqued todestruction without failure in the weld.

7.6.6.3 Tension Test. Studs shall be tension tested todestruction using any machine capable of supplying therequired force. A stud application shall be consideredqualified if none of the test specimens fail in the weld.


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7.6.7 Application Qualification Test Data shall includethe following:

(1) Drawings that show shapes and dimensions ofstuds and arc shields

(2) A complete description of stud and base materialsand a description (part number) of the arc shield

(3) Welding position and settings (current, time)

(4) A record which shall be made for each qualifica-tion and that record shall be available for each contract

7.7 Production Control7.7.1 Preproduction Testing

7.7.1.1 Before production welding with a particularsetup (see 7.5.4.2) and with a given size and type of stud,and at the beginning of each day’s or shift’s production,testing shall be performed on the first two studs that arewelded. The stud technique may be developed on a pieceof material similar to the production member in thicknessand properties. If actual production thickness is notavailable, the thickness may vary plus or minus 25%. Alltest studs shall be welded in the same general position asrequired on the production member (flat, vertical, oroverhead).

7.7.1.2 Instead of being welded to separate material,the test studs may be welded on the production member,except when separate plates are required by 7.7.1.5.

7.7.1.3 The test studs shall be visually examined.They shall exhibit full 360° flash.

7.7.1.4 In addition to visual examination, the test shallconsist of bending the studs after they are allowed tocool, to an angle of approximately 30° from their originalaxes by either striking the studs on the head with a ham-mer or placing a pipe or other suitable hollow deviceover the stud and manually or mechanically bending thestud. At temperatures below 10°C [50°F], bending shallpreferably be done by continuous slow application ofload. For threaded studs, the torque test of Figure 7.3shall be substituted for the bend test.

7.7.1.5 If on visual examination the test studs do notexhibit 360° flash, or if on testing, failure occurs in theweld zone of either stud, the WPS shall be corrected, andtwo more studs shall be welded to separate material or onthe production member and tested in conformance withthe provisions of 7.7.1.3 and 7.7.1.4. If either of the sec-ond two studs fails, additional welding shall be contin-ued on separate plates until two consecutive studs are

tested and found to be satisfactory before any more pro-duction studs are welded to the member.

7.7.2 Production Welding. Once production weldinghas begun, any changes made to the welding setup (see7.5.4.2) as determined in 7.7.1 shall require that the test-ing in 7.7.1.3 and 7.7.1.4 be performed prior to resumingproduction welding.

7.7.3 In production, studs on which a full 360° flash isnot obtained may, at the option of the Contractor, berepaired by adding the minimum fillet weld as requiredby 7.5.5 in place of the missing flash. The repair weldshall extend at least 10 mm [3/8 in] beyond each end ofthe discontinuity being repaired.

7.7.4 Operator Qualification

7.7.4.1 The preproduction test required by 7.7.1, ifsuccessful, shall also serve to qualify the stud weldingoperator.

7.7.4.2 Before any production studs are welded by anoperator not involved in the preproduction setup of 7.7.1,the first two studs welded by the operator shall be testedin conformance with 7.7.1.3 and 7.7.1.4. When two con-secutively welded studs have been tested and found satis-factory, the operator may then weld production studs.

7.7.5 If an unacceptable stud has been removed from acomponent subjected to tensile stresses, the area fromwhich the stud was removed shall be made smooth andflush.

7.7.5.1 Where in such areas the base metal has beenpulled out in the course of stud removal, SMAW withlow-hydrogen electrodes in conformance with the require-ments of this code shall be used to fill the pockets, andthe weld surface shall be ground flush.

7.7.5.2 In compression areas of members, if stud fail-ures are confined to shanks or fusion zones of studs, anew stud may be welded adjacent to each unacceptablearea in lieu of repair and replacement on the existingweld area (see 7.4.3). If base metal is pulled out duringstud removal, the repair provisions shall be the same asfor tension areas, except that when the depth of disconti-nuity is the lesser of 3 mm [1/8 in] or 7% of the base-metal thickness, the discontinuity may be faired bygrinding in lieu of filling with weld metal.

7.7.5.3 Where a replacement stud is to be provided,the base-metal repair shall be made prior to welding thereplacement stud.


171

7.7.5.4 Replacement studs (other than threaded typewhich should be torque tested) shall be tested by bendingto an angle of approximately 15° from their original axis.

7.7.5.5 The areas of components exposed to view incompleted structures shall be made smooth and flushwhere a stud has been removed.

7.8 Inspection Requirements7.8.1 If visual inspection reveals any stud that does notshow a full 360° flash or any stud that has been repairedby welding, such stud shall be bent to an angle ofapproximately 15° from its original axis.

7.8.2 The method of bending shall be in conformancewith 7.7.1.4. The direction of bending for studs with lessthan a 360° flash shall be opposite to the missing portionof the flash.

7.8.3 Threaded studs shall be torque tested. Torque test-ing shall be in conformance with Figure 7.3.

7.8.4 The inspector, where conditions warrant, mayselect a reasonable number of additional studs to be sub-jected to the tests described in 7.8.1.

7.8.5 The bent stud shear connectors (Type B) and otherstuds to be embedded in concrete (Type A) that show nosign of failure shall be acceptable for use and left inthe bent position. All bending and straightening whenrequired shall be done without heating, before comple-tion of the production stud welding operation, except asotherwise provided in the contract.

7.8.6 If, in the judgment of the Engineer, studs weldedduring the progress of the work are not in conformancewith code provisions, as indicated by inspection and test-ing, corrective action shall be required of the Contractorat the Contractor’s expense. The Contractor shall makethe setup changes necessary to insure that studs subse-quently welded will meet code requirements.

7.8.7 At the option and the expense of the Owner, theContractor may be required, at any time, to submit studsof the types used under the contract for a qualificationcheck in conformance with the procedures of Annex E.

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Table 7.1Mechanical Property Requirements for Studs (see 7.3.1.2)

Type Aa Type Bb

Tensile strength 380 MPa [55 ksi] min. 415 MPa [60 ksi] min.

Yield strength (0.2% offset) — 345 MPa [50 ksi] min.

Elongation (% in 50 mm [2 in]) 17% min. 20% min.

Reduction of area 50% min. 50% min.

a Type A studs shall be general purpose of any type and size used for purposes other than shear transfer in composite beam design and construction.b Type B studs shall be studs that are headed, bent, or of other configuration in 12 mm [1/2 in] through 23 mm [7/8 in] diameter that are used as an

essential component in composite beam design and construction.

Table 7.2Minimum Fillet Weld Size for Small Diameter Studs (see 7.5.5.1)

Stud Diameter, φ, mm [in] Minimum Fillet Weld Size, mm [in]

φ ≤ 10 [3/8]10 [3/8] < φ ≤ 25 [1]

φ > 25 [1]

6 [1/4]8 [5/16]

10 [3/8]

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a L = manufactured length—length specified by Engineer plusupset distance.

Figure 7.1—Dimension and Tolerances ofStandard-Type Shear Connectors (see 7.2.1)

Standard Dimensions, mm [in]

Shank Diameter(C)

Length Tolerance

(L)

HeadDiameter

(H)

MinimumHead Height

(T)

12.7[1/2]

+0.00–0.25 [–0.010]

±1.60[±1/16]

25.4 ± 0.40-00[1 ± 1/64]

7.1[9/32]

15.9[5/8]

+0.00–0.25 [–0.010]

±1.60[±1/16]

31.7 ± 0.4-[1-1/4 ± 1/64]

7.1[9/32]

19.0[3/4]

+0.00–0.38 [–0.015]

±1.60[±1/16]

31.7 ± 0.4-[1-1/4 ± 1/64]

9.5[3/8]

22.1[7/8]

+0.00–0.38 [–0.015]

±1.60[±1/16]

34.9 ± 0.4-[1-3/8 ± 1/64]

9.5[3/8]

25.4[1]

+0.00–0.38 [–0.015]

±1.60[±1/16]

41.3 ± 0.4-[1-5/8 ± 1/64]

12.7[1/2]

Figure 7.2—Typical TensionTest Fixture (see 7.3.2)

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Note: The dimensions shall be appropriate to the size of thestud. The threads of the stud shall be clean and free of lubricantother than the residue of cutting oil.

Figure 7.3—Torque Testing Arrangementand Table of Testing Torques (see 7.6.6.2)

Required Torque for Testing Threaded Studs

Nominal Diameter and Thread Pitch (mm) Testing Torque (J)

M 6 × 1M 8 × 1.25M 10 × 1.5M 12 × 1.75M 14 × 2M 16 × 2M 20 × 2.5M 22 × 2.5M 24 × 3

612205073

100180285430

Required Torque for Testing Threaded Studs

Nominal Diameterof Studs

[in]

Threads per inchand SeriesDesignated

Testing Torque(ft·lb)

1/41/4

28 UNF20 UNC

5.04.2

5/165/16

24 UNF18 UNC

9.58.6

3/83/8

24 UNF16 UNC

17.015.0

7/167/16

20 UNF14 UNC

27.024.0

1/21/2

20 UNF13 UNC

42.037.0

9/169/16

18 UNF12 UNC

60.054.0

5/85/8

18 UNF11 UNC

84.074.0

3/43/4

16 UNF10 UNC

147.0132.0

7/87/8

14 UNF9 UNC

234.0212.0

1.01.0

12 UNF8 UNC

348.0318.0


175

NO APPLICATIONS WITHIN THIS CODE

8. Statically Loaded Structures


176



177

THE PROVISIONS OF THIS CLAUSE IN AASHTO/AWS D1.5-96 WEREDISTRIBUTED THROUGHOUT AASHTO/AWS D1.5M/D1.5:2002,

AND REMAIN SO FOR THIS EDITION.

9. Welded Steel Bridges


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179


10. Tubular Structures


180



181


11. Strengthening and Repairing Existing Structures


182



183

12.1 General ProvisionsThis clause shall apply to fracture critical nonredundantmembers. All steel bridge members and member compo-nents designated on the plans or elsewhere in the contractdocuments as fracture critical shall be subject to the addi-tional provisions of this section. All other provisions ofthe code shall apply to the construction of fracture criti-cal members (FCMs), except as modified or supple-mented herein. Should any provision of this section be inconflict with other provisions of the code, the require-ments of this section shall apply.

12.2 Definitions12.2.1 Fracture Control Plan (FCP). The designation“FCP” shall mean fracture control plan and shall includeall provisions of this section of the code.

12.2.2 Fracture Critical Member (FCM). Fracture criti-cal members or member components are tension membersor tension components of bending members (includingthose subject to reversal of stress), the failure of whichwould be expected to result in collapse of the bridge. Thedesignation “FCM” shall mean fracture critical memberor member component. Members and components that arenot subject to tensile stress under any condition of live-load shall not be defined as fracture critical.

12.2.2.1 Attachments. Any attachment welded to atension zone of an FCM member shall be considered anFCM when any dimension of the attachment exceeds100 mm [4 in] in the direction parallel to the calculatedtensile stress in the FCM. Attachments designated FCMshall meet all requirements of this FCP.

12.2.2.2 Welds. All welds to FCMs shall be consid-ered fracture critical and shall conform to the require-ments of this FCP. Welds to compression members orcompression areas of bending members shall not bedefined as fracture critical.

12.3 Contract Documents12.3.1 Design Evaluation. The Engineer shall evaluateeach bridge design to determine the location of anyFCMs that may exist and shall ensure that all FCMs areproperly designated as required by 12.3.2. The Engineershall ensure that the contract documents contain all infor-mation necessary to order materials and properly con-struct FCMs as required by the design.

12.3.2 Prebid Designation of FCMs. All fracture criti-cal members shall be identified on the plans, or other-wise described in the contract documents by theEngineer prior to bidding. Each FCM shall be individu-ally designated. Each portion of a bending member thatis fracture critical shall be clearly described giving thelimits of the FCM. Within these limits, the provisions of12.2.2 shall apply.

12.3.3 Shop Drawings. Shop drawings shall meet therequirements of 2.1.

12.3.3.1 Engineer’s Review. The Engineer shallreview all shop drawings to ensure that the Contractorhas identified all FCMs. The Engineer shall check eachshop drawing, including materials lists, for conformancewith this FCP and the contract documents. WPSs forconstruction and repair are considered integral parts ofshop drawings and shall be reviewed for acceptability.An indication of the Engineer’s disposition of each draw-ing and procedure shall be shown by appropriate stamp,signature and date.

12.3.3.2 Acceptance. The Contractor shall providedetailed shop drawings and WPSs for review by theEngineer, whose acceptance, or acceptance-as-noted,shall be required prior to fabrication. Such acceptanceshall be limited to mean the reviewed material appears toconform to the intent of the contract documents (includ-ing this FCP). The Contractor shall be responsible forproducing acceptable work.

12. AASHTO/AWS Fracture Control Plan (FCP)for Nonredundant Members

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12.4 Base Metal Requirements12.4.1 Approved Base Metals. All steels described in1.2.2 are approved for use in the construction of FCMs.Other steels may be approved by the Engineer.

12.4.2 Fine-Grain Practice. Mill orders shall specifykilled fine-grain practice for steel used in FCMs.

12.4.3 Prohibition of Mill Repairs. Mill order shallstipulate that no welded repairs shall be performed by theproducing mill.

12.4.4 Optional Base Metal Requirements. When thecontract documents require heat treatment, toughness,chemistry, or other provisions that are not part ofAASHTO M270M [M270] (ASTM A 709M [A 709]), orthis FCP, these requirements shall be described in themill order.

12.4.4.1 Optional Through-Thickness and Low-Sulfur Requirements. The Engineer may, when deemednecessary due to significant applied tensile stress in thethrough-thickness (Z) direction at specific locations inthe structure, specify that individual plates shall havelow sulfur (0.010% maximum) or improved through-thickness properties (20% reduction of area as describedin ASTM A 770/A 770M), or both. Each plate requiredto have low sulfur and improved through-thickness prop-erties shall be clearly identified on the plans. All require-ments for such steels in addition to the requirements ofthis FCP shall be specified in the contract documents.

12.4.4.2 Optional Heat Treatment. The Engineermay order individual plates or parts to be normalized, orquenched and tempered, for special applications. Allmanufacturing requirements, such as forging, heat treat-ment, and testing requirements not part of the AASHTOmaterial specifications, shall be clearly specified in thecontract documents. The minimum CVN toughness val-ues required at specific test temperatures shall be stated.

12.4.5 Toughness. The toughness of base-metal shapes,plates, and bars shall be as specified in AASHTOM270M [M270] (ASTM A 709M [A 709]) for FractureCritical Impact Test Requirements. The Grade of Steel,Method of Joining and AASHTO Temperature Zone inwhich the structure will be constructed shall be noted inthe mill order.

12.4.5.1 Supplementary Requirements. Individualsteel plates may be specified to have a toughness exceed-ing the minimums described in 12.4.5 by listing specialrequirements in the contract documents. This exceptionto routine design practice, if deemed necessary, shouldbe restricted to unusually critical applications, for exam-ple, suspended span bridge hangers. Each plate required

to meet special toughness requirements shall be clearlyidentified.

12.4.5.2 Mill Orders. Mill orders shall specify sup-plementary requirements for CVN test values meetingthe requirements of this FCP.

12.4.6 Base Metal Identification. When heat numbersand other identification markings are applied by diestamping, low-stress dies shall be used.

12.5 Welding Processes12.5.1 Approved Processes. SMAW, SAW, FCAW,and GMAW with metal cored electrodes may be used toconstruct or repair FCMs.

12.5.2 Prohibited Processes and Procedure Restric-tions. ESW and EGW shall be prohibited for weldingFCMs. GMAW (except as allowed in 12.5.1) may onlybe used with the approval of the Engineer. WhenGMAW (except as allowed in 12.5.1) is allowed, qualifi-cation tests, procedure control and NDT shall be as spec-ified by the Engineer.

12.5.3 Preferred Processes and Procedures. The Engi-neer may designate the use of specific processes, or pro-cess controls for specific bridge welds. All specialprovisions shall be specified in the contract documents.Other restrictions on the use of welding processes orprocedures, if any, shall be described in the contractdocuments.

12.6 Consumable Requirements12.6.1 Heat or Lot Testing. All welding consumablesshall be heat or lot tested by the manufacturer to deter-mine conformance with the requirements of this FCP.Certified copies of test results shall be provided to theEngineer. Heat and lot shall be as defined in the latestedition of AWS A5.01, Filler Metal Procurement Guide-lines. Consumables shall be tested by welding as speci-fied in the appropriate AWS filler metal specifications.All tests required by AWS A5.01, Schedule J, shall beperformed and reported.

During welding consumable testing, materials of thesame specification and manufacture, but not necessarilythe same heat or lot to be combined during productionwelding shall be used. For example, a specific heat or lotof SAW electrode need not be tested with the specific lotof SAW flux that will be used in production welding,provided both meet all other requirements of the FCPand are representative of the consumables to befurnished.

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12.6.1.1 Exemptions. Welding consumables pro-duced under continuing quality assurance programsaudited and approved by one or more of the followingagencies shall be exempt from the heat and lot testingrequirements of 12.6.1.

(1) American Bureau of Shipping (ABS)

(2) Lloyd’s Register of Shipping

(3) American Society of Mechanical Engineers(ASME)

12.6.2 Diffusible Hydrogen of Weld Metal

12.6.2.1 Testing. Except for SMAW, which shall bemonitored on the basis of electrode-coating moisturecontent, tests shall be conducted on welds produced dur-ing classification testing to determine the amount of dif-fusible hydrogen per 100 g of weld metal. Diffusiblehydrogen tests shall be performed under mercury or bythe gas chromatograph method as specified in AWSA4.3, Standard Methods for Determination of the Diffus-ible Hydrogen Content of Martensitic, Bainitic, and Fer-ritic Steel Weld Metal Produced by Arc Welding. Testingshall be done by heat and lot of welding consumable asdescribed in 12.6. When welding consumables areaccepted as described in 12.6.1.1, heat and lot testingshall be waived, provided the certificate of conformancelists diffusible hydrogen or coating moisture content testresults, as appropriate, obtained during classificationtesting.

Production welds shall not be required to be tested fordiffusible hydrogen.

12.6.2.2 Electrode Optional Supplemental Mois-ture-Resistant Designator Requirements for TackWelding. SMAW electrodes used for tack welding asdescribed in 12.13.1.2 on steel that is not preheated shallconform to the AWS filler metal specifications optionalsupplemental diffusible hydrogen designator H4. Elec-trodes classified with the optional R designator andE7018M electrodes may also be used for tack weldingsteel that is not preheated. Such electrodes shall have acoating moisture content consistent with the optionalsupplemental diffusible hydrogen designator H4.

12.6.2.3 Electrode Optional Supplemental Mois-ture-Resistant Designator Requirements for Welding.SMAW electrodes used to weld base metal with a mini-mum specified yield strength of 345 MPa [50 ksi] or lessshall conform to the diffusible hydrogen requirements ofthe AWS filler metal specifications optional supplemen-tal designator H4, H8, or H16. All SMAW electrodesused to weld base metal with a minimum specified yieldstrength greater than 345 MPa [50 ksi] shall conform tothe diffusible hydrogen requirements of the AWS filler

metal specification optional supplemental designator H4or H8.

12.6.2.4 Special Requirements. Filler metal manu-facturers shall specify any special precautions in excessof those contained in this FCP that are necessary toensure the deposited weld metal shall meet the diffusiblehydrogen limits of the specified classification when theconsumables are removed from protective packaging andused without delay. Special storage provisions, maxi-mum storage life, special handling and WPSs, if any,shall be completely described.

12.6.3 Weld Metal Strength and Ductility Require-ments. Weld metal strength and ductility shall conformto the requirements of Tables 4.1 and 4.2 unless other-wise provided in the contract documents.

12.6.4 Weld Metal Toughness Requirements

12.6.4.1 Matching Strength Groove Welds. Groovewelds required to have a yield strength equal to the mini-mum specified yield strength of the base metal shall havea CVN test value equal to, or exceeding that, specified inTable 12.1.

12.6.4.2 Undermatching Strength Welds. All weldsallowed to have undermatching yield strength shall havea minimum CVN test value of 34 J [25 ft∙lb] @ –30°C[–20°F].

12.6.5 SMAW

12.6.5.1 SMAW Electrodes. All SMAW electrodesshall be manufactured, packaged in hermetically sealedcontainers, stored, transported and delivered so thatwhen removed from the container, the electrodes areundamaged and meet the diffusible hydrogen limits spec-ified in 12.6.2.

12.6.5.2 Sealed Containers. Manufacturers’ contain-ers shall remain sealed until the electrodes are dispensedfor work or are placed in heated storage as specified in12.6.5.3. Containers shall be examined and if the her-metic seal was lost before opening, electrodes shall notbe used for FCM welding. Electrodes shall be examinedto ensure there is no damage that may adversely affectweld quality, including previously wet, contaminated orbroken coatings. Any electrodes with such defects intheir usable length shall be discarded.

12.6.5.3 Storage. After removal from the manufac-turer’s sealed container, electrodes not immediately dis-pensed for use shall be continuously stored in anelectrically heated, thermostatically controlled ovens at aminimum temperature of 120°C [250°F] until dispensedfor use in the work. If the temperature falls below 120°C[250°F], electrodes shall be dried or redried per 12.6.5.4.


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12.6.5.4 Drying Temperatures. As used here, theterms dried and drying are defined as holding electrodesat a specified temperature for a minimum period of time(below) or according to the manufacturer’s requirements.Unless the manufacturer stipulates otherwise based ontesting, electrodes for base metal with a specified mini-mum yield strength of 345 MPa [50 ksi] or less shall bedried at 230°C–290°C [450°F–550°F] for a minimumperiod of four hours, and electrodes for matching higherstrength base metal shall be dried at 425°C–540°C[800°F–1000°F] for two hours. The terms redried andredrying are defined as drying a second time, whether theinitial drying followed exposure or was based on manu-facturer’s requirements. If the temperature inside thestorage oven falls to between 50°C [125°F] and 110°C[225°F] for a period of up to eight hours, or below 50°C[125°F] for up to four hours, electrodes which were notpreviously redried shall be dried or redried or shall not beused to weld FCMs. Electrodes in storage ovens exposedto temperatures below 120°C [250°F] and times beyondthe limits described above, or that were previouslyredried shall not be used.

12.6.5.5 Storage and Drying Ovens. Electrode ovensshall be designed for the storage, segregation, and dryingof electrodes and shall be capable of maintaining a speci-fied temperature between 120°C–290°C [250°F–550°F].Each oven shall have a thermally sealed, latching doorthat is closed when not charging or discharging elec-trodes. To regularly verify the inside temperature with-out opening the door, each oven shall have eitherinstrumentation allowing direct reading or a small portthrough which a thermometer can be inserted. Such portsshall be closed when not in use. Regardless of type, alloven temperature sensors shall be verified at least onceper year.

12.6.5.6 Maximum Atmospheric Exposure ofSMAW Electrodes. Except as provided in 12.6.5.8,SMAW electrodes exposed to the atmosphere for periodsof time greater than those specified in Table 4.7 shall bedried or redried, or shall not be used to weld FCMs asstipulated in 12.6.5.7 or 12.6.5.9.

12.6.5.7 Electrode Exposure Limits. E70XX andE80XX-X electrodes not designated moisture resistantwhich are exposed up to but not exceeding the time limitof Table 4.7, and moisture resistant electrodes exposedup to but not exceeding the time limits in 12.6.5.8, maybe dried or redried and then either returned to continu-ously heated storage or dispensed for use in the work.Electrodes shall not be redried more than once.

12.6.5.8 Optional Supplemental Moisture-Resis-tant Designators. Prior to drying, electrodes with theAWS filler metal specifications optional supplemental

moisture resistance designator “R” may be exposed tothe atmosphere for up to nine hours when welding steelswith a specified minimum yield strength of 345 MPa[50 ksi] or less. After drying or redrying, these elec-trodes shall be governed by the exposure limits in Table4.7. Moisture-resistant electrodes and their containersshall bear the additional designator R. Electrodes shallnot be redried more than once.

12.6.5.9 Electrodes for Grades HPS 485W [HPS70W], 690/690W [100/100W] Steels. Electrodes formatching strength welds on Grade HPS 485W [HPS70W] and 690/690W [100/100W] steels shall be usedwithin the maximum atmospheric exposure limits ofTable 4.7. When such electrodes’ exposure exceedsTable 4.7 limits by less than one hour, they shall be driedor redried before being returned to heated storage or dis-pensed for use. Matching strength electrodes exposedmore than one hour beyond Table 4.7 limits shall not beused for FCM welds. E70XX and E80XX electrodes forundermatched welds shall follow the requirements of12.6.5.7. Electrodes shall not be redried more than once.

12.6.5.10 Production Welding Electrode Usage.Electrodes removed from heated storage shall be dis-pensed directly to welders for immediate use. They shallbe kept in containers that protect them from contamina-tion by moisture, oil, grease, and other sources of hydro-gen, until used. The containers (scabbards) may be openat the top. Welders shall not be given more electrodesthan can be used within the exposure limits allowed bythis FCP.

12.6.6 SAW

12.6.6.1 Diffusible Hydrogen. All SAW electrodesand fluxes used to weld base metal with minimum speci-fied yield strength of 345 MPa [50 ksi] or less shall con-form to the diffusible hydrogen requirements of theAWS filler metal specifications optional supplementaldesignator H4, H8, or H16. All SAW electrodes andfluxes used to weld base metal with a minimum specifiedyield strength greater than 345 MPa [50 ksi] shall con-form to the diffusible hydrogen requirements of theAWS filler metal specifications optional supplementaldesignator H4 or H8.

12.6.6.2 Electrode and Flux Packaging. Electrodesshall be received in packaging that protects the electrodeand coatings, if present, from damage. When removedfrom protective packaging and installed on machines,care shall be taken to protect the electrodes and coatings,if present, from deterioration or damage. No one shallmodify or lubricate an electrode after manufacture forany reason. Flux shall be received in moisture-resistantpackaging, transported and stored in a manner that willpreserve the original manufactured condition. Flux from


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containers and packages that have been broken or openedprior to use shall not be used to weld FCMs.

12.6.6.3 Flux Handling and Drying (Baking). All ofthe contents of each container of SAW flux shall beplaced in an approved storage and drying oven directlyupon opening the flux to the atmosphere. All flux shallbe baked at 290°C [550°F] minimum for at least twohours, or as recommended by the manufacturer, and thenstored continuously at 120°C [250°F] minimum untildispensed for use. Hot make-up flux may be carried tomachines in steel pails and stored at the point of weldingfor up to four hours, provided the flux is protected fromcontamination by an appropriate cover.

12.6.6.4 Drying and Storage Temperatures. Fluxdrying and storage ovens shall be electrically heated andthermostatically controlled to provide temperatures of120°C–290°C [250°F–550°F]. Flux ovens shall be capa-ble of drying and storing flux without causing a break-down in particle size or segregation of components.Openings for charging and discharging of flux shall beclosed when not in use. Each oven shall have a small portthat may be opened briefly to insert a thermometer tomeasure the temperature of the oven without opening thedoor. The port shall be kept shut when not in use. Alter-natively, ovens may be furnished with thermometers thatallow direct reading of the inside temperature withoutopening the oven.

12.6.6.5 Discharge and Refill of Flux Hoppers.Welding machine flux hoppers and pressure containersshall be emptied of flux, entrapped fines and other parti-cles, each time welding is suspended for 10 hours ormore. Just prior to the resumption of welding, the hop-pers and containers shall be refilled with new, properlydried, flux taken directly from a storage or baking oven.

12.6.6.6 Open Top Flux Systems. When open top,hopper-type flux systems have not been refilled, or weld-ing has been suspended for six hours, the top 10 mm[3/8 in] of flux in the hopper shall be removed andappropriate make-up flux added before welding isresumed.

12.6.6.7 Time Limits for Flux Replacement. Thetime limits of 12.6.6.5 and 12.6.6.6 may be extendedbased upon the results of tests acceptable to the Engi-neer. Tests conducted to demonstrate that the diffusiblehydrogen limits of this FCP can be met without replacingflux as required by the referenced subclauses shallinclude, as a minimum, a description of the welding andflux-handling system, the relative humidity during test-ing, and the results of mercury or gas chromatograph dif-fusible hydrogen tests conducted in conformance withAWS A4.3. To be acceptable, diffusible hydrogen testsafter extended time without replacement shall conform to

the requirements of the optional diffusible hydrogen des-ignator of the filler metal and flux being used.

12.6.6.8 Pneumatic Flux Delivery Systems. Com-pressed air used in pneumatic flux delivery systems shallbe effectively filtered and dried to remove moisture, oil,rust and other contaminants. Dryers, unless automati-cally drained, shall be manually drained daily to ensureproper operation. Air lines shall be checked by ventingthe line to the atmosphere away from the work wheneverthe pressure container is refilled to verify the air is cleanand dry.

12.6.6.9 Flux Recovery. Unfused flux may be recov-ered from clean base-metal surfaces and reused asdescribed in 4.8.4. Flux may be recovered directly backinto welding machine flux containers, provided it isrecovered within a maximum of five minutes of beingdeposited on the steel. Flux recovered within a maximumof one hour may be returned to a flux drying oven. Fluxexposed to the atmosphere for more than one hour afterwelding, and all flux that cannot be recovered fromclean, dry, metal surfaces, shall be discarded. Recoveredflux to be redried shall be held at a temperature of 290°C[550°F] minimum for at least two hours, or as recom-mended by the manufacturer, before reuse.

12.6.6.10 Recovered Flux. When flux is recovered, atleast one third of the total flux used in welding shall beproperly dried new flux. It shall be added in a way thatwill ensure mixing with the recovered flux in conform-ance with 4.8.4. A written description of the Contractor’sflux recovery procedure shall be available for examina-tion by welders and Inspectors.

12.6.6.11 Gravity Feed Delivery Systems. Operatorsof welders with gravity feed flux delivery systems mayreturn flux directly back to the hopper during weldingas provided in 12.6.6.9. During welding, properly driednew make-up flux representing at least 1/3 of the totalvolume shall be added at least hourly as weldingprogresses.

12.6.7 FCAW and GMAW (Metal Cored) Electrodes

12.6.7.1 Diffusible Hydrogen. All FCAW andGMAW (metal cored) electrodes used to weld base metalwith minimum specified yield strength of 345 MPa[50 ksi] or less shall conform to the diffusible hydrogenrequirements of the AWS filler metal specificationsoptional supplemental designator H4, H8, or H16. AllFCAW and GMAW (metal cored) electrodes used toweld base metal with a minimum specified yield strengthgreater than 345 MPa [50 ksi] shall conform to the dif-fusible hydrogen requirements of the AWS filler metalspecifications optional supplemental designator H4 orH8.


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12.6.7.2 Electrode Packaging. FCAW and GMAW(metal cored) electrodes shall be received in moisture-resistant packages that are undamaged. They shall beprotected against contamination and injury during ship-ment and storage. Electrode packages shall remain effec-tively sealed against moisture until the electrode isrequired for use. When removed from protective packag-ing and installed on machines, care shall be taken to pro-tect the electrodes and coatings, if present, fromdeterioration or damage. No one shall modify or lubri-cate an electrode after manufacture for any reason exceptthat drying may be used when recommended by themanufacturer.

12.6.7.3 Shielding Gas. Any shielding gas or gasmixture qualified as described in 5.12 or 5.13 may beused. The manufacturer shall provide certification thatthe gas or gas mixture conforms to the requirements of4.13.

12.6.7.4 Electrode Storage. When welding is to besuspended for more than 8 hours, electrodes shall beremoved from the machines and stored in airtight cover-ings or placed in a storage oven maintained at a tempera-ture between 120°C and 290°C [250°F and 550°F] basedon recommendations by the manufacturer.

Electrodes not consumed before accumulating 24 hoursof exposure outside sealed or heated storage shall eitherbe redried once as described in 12.6.7.6 or not be usedfor FCM welding. Electrode support shall be identifiedto facilitate monitoring of total atmospheric exposuretime.

12.6.7.5 Time Limit Extension for Electrode Expo-sure. The time limits of 12.6.7.4 may be extended basedupon the results of tests acceptable to the Engineer. Testsconducted to demonstrate that the diffusible hydrogenlimits of this FCP can be met at periods of exposuregreater than specified in 12.6.7.4 shall include, as a mini-mum, a description of the maximum electrode atmo-spheric exposure time, the relative humidity duringelectrode exposure and weld testing, and the results ofmercury or gas chromatograph diffusible hydrogen testsconducted in conformance with AWS A4.3. To beacceptable, diffusible hydrogen tests after extendedexposure shall conform to the requirements of theoptional supplemental diffusible hydrogen designator forthe filler metal specified.

12.6.7.6 Drying Temperatures. When approved bythe manufacturer, FCAW and GMAW (metal cored)electrodes on metal supports may be dried once at260°C–290°C [500°F–550°F] for a minimum four hours,or as otherwise specified by the manufacturer in writing,to restore their condition. If the electrode or the electrode

support is damaged by baking, the electrode shall not beused to weld FCMs.

12.7 Welding Procedure Specification (WPS)

The provisions of Clause 5 shall apply, except as modi-fied by 12.7. WPS qualification shall be performed per5.12 or 5.13. Filler metals and fluxes used for WPS qual-ification testing shall not be subject to the requirementsof 12.6, or 12.6.2, provided the WPS and PQR show thesame manufacturer’s brand and type of filler metal andflux was used.

12.7.1 Limited Prequalification for SMAW. WPSsusing SMAW electrodes classified as E7016, E7018,E7018-1 and E8018-X, including those with the “C”alloy and “M” military classifications and the optionalsupplemental designator “R” designating moisture resis-tance, shall be prequalified and exempt from WPS quali-fication test. All WPSs using other SMAW electrodesshall be qualified by tests as described in 5.12 or 5.13 inaddition to the tests performed by the manufacturer forelectrode classification.

12.7.2 Groove WPS Qualification. Except as providedin 12.7.1, groove WPSs shall be qualified by testing inconformance with 5.12 or 5.13. CVN test values shall beas specified in 12.6.4.

12.7.3 Fillet WPS Qualification. Except as provided in12.7.1, fillet WPSs shall be qualified by groove weldtesting in conformance with 5.12 or 5.13. In addition, fil-let weld tests shall be conducted as specified in 5.10.3.Fillet weld tests shall be conducted using welding vari-ables qualified as described in 5.12 or 5.13.

12.7.4 Period of Effectiveness. When a specific Con-tractor has not previously performed a WPS qualificationtest satisfying the provisions of this or a previousAASHTO FCP, the required tests shall be completedwithin one year prior to the start of production welding.All subsequent tests shall be conducted at a frequencythat will ensure no PQR used as a basis for preparation ofWPSs is more than 36 months old.

12.7.5 Previous Qualification. The Engineer shouldaccept evidence of previous qualification, provided thetests were performed in conformance with the require-ments of this FCP (see 5.3).

12.8 Certification and QualificationContractors shall be certified under the AISC (AmericanInstitute of Steel Construction) Quality Certification


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Program, Category III, Major Steel Bridges with Frac-ture Critical Rating, or an equivalent program acceptableto the Engineer.

12.8.1 Individual Competence. All persons that con-struct, inspect, or test FCMs shall be competent to per-form the tasks they are assigned to perform.

12.8.2 Welding Personnel Qualification. All welders,including welding operators and tack welders, shall bequalified by test within 6 months before beginning pro-duction welding or shall be regularly requalified on anannual basis. Upon beginning work on a Fracture Criticalproject, the qualification of a welder or welding operatorshall be considered valid until the project is completedprovided the welder or welding operator meets the conti-nuity requirements of 5.21.4. For welders and weldingoperators performing Fracture Critical CJP groovewelds, initial qualification shall be based upon accept-able results of both mechanical (bend) tests and radiog-raphy as described in Clause 5, Part B. Welders andwelding operators performing Fracture Critical filletwelding shall be qualified based upon acceptable resultsof Clause 5, Part B. Tack welders shall be qualified asdescribed in Clause 5, Part B. Annual requalificationmay be based upon acceptable results of radiography ofproduction groove welds (for CJP groove welders) or testplates as approved by the Engineer.

12.9 As-Received Inspection of Base Metal

All base-metal surfaces and edges shall be visuallyinspected for discontinuities. The standards for visualacceptance of shape, plate, and bar-rolled surfaces shallbe as described in AASHTO M160 [M160M] (ASTMA 6 [A 6M]) unless otherwise provided in the contractdocuments.

12.10 Thermal CuttingEdges and ends of plates shall be cut to size by thermalcutting. Universal mill and sheared plates shall have aminimum of 5 mm [3/16 in] of material removed fromrolled or sheared edges and from ends by thermal cuttingprior to assembly and welding. This provision shall notapply to edges of bars and shapes as defined in AASHTOM160 [M160M] (ASTM A 6 [A 6M]), or the ends ofstiffeners and connection plates where there is no calcu-lated tensile stress.

12.10.1 Thermal-Cut Edge Requirements. Thermal-cut edges (TCEs) shall meet the requirements of 3.2unless otherwise specified in the contract documents.

12.10.2 MT. Visually-detected discontinuities shall beinspected further using the Yoke method of MTdescribed in 6.7.6.2.

12.10.3 Laminar Discontinuities. No laminar disconti-nuities shall be allowed in the fusion face of groovewelds in butt joints subject to calculated tensile stressnormal to the weld axis, or in the sides (edges) of contig-uous base metal within 300 mm [12 in] of such welds.

12.10.4 Allowable Discontinuities. Except as providedin 12.10.3, base metal at the fusion face of butt, T-, andcorner joints may have discontinuities allowed by 3.2.Repair welding, if any, shall be done in conformancewith 12.17.3. Excavated, or repaired, surfaces shall befinished to produce conditions suitable for final welding.

12.11 Repair of Base Metal

Base-metal discontinuities adjacent to fracture-criticalbutt joints as described in 12.10.3 shall be repairedor replaced by the Contractor in conformance with thefollowing options:

12.11.1 Rotation of Base Metal. The base metal may berotated end for end when it is possible to remove discon-tinuities from areas subject to calculated tensile stress.

12.11.2 Thermal Cutting. When the unacceptable dis-continuities are localized, these may be removed by ther-mal cutting to sound metal, reducing the length of theeffected plate, bar, or shape. This requires adjacentpieces of steel to be extended beyond their detailedlength and mandates relocation of the affected butt joint.Relocation of butt welds from their detailed locationshall require approval by the Engineer. All changes inweld location shall be recorded on the shop drawings.

12.11.3 Repairs. Repairs may be made by welding asdescribed in 12.17.

12.11.4 Replacement. With the Engineer’s approval, theContractor may remove a defective portion of the basemetal and replace it with new material of the same orgreater strength, toughness, and corrosion resistance,except Grades HPS 485W [HPS 70W] and 690/690W[100/100W] shall not be substituted for lower strengthsteels. Replacement steel and welds necessary to affectthe base-metal substitution shall conform to all require-ments of the FCP. Unless otherwise approved by theEngineer, the minimum replacement length shall be 1.5m [5 ft]. All base metal replacements shall be recorded inthe inspection records and shop drawings.


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12.12 Straightening, Curving, and Cambering

Cold bending shall be prohibited for all fracture criticalsteels. Bent and distorted material may be corrected priorto assembly and welding by approved upset-shorteningmethods (heat straightening, curving and cambering).Finished FCMs constructed of as-rolled and normalizedsteels may be heated to produce slight reductions inexcessive camber as described in 3.2.7, or to produce acurvature equivalent to a circular radius not less than300 m [1000 ft]. All heating corrections to straightnessand camber and heat curving shall be done by heat-shrink methods described in 3.7.3.

Exceptions to the provisions of this subclause shallrequire the Engineer’s approval.

No permanent welds or base metal shall be removed orcut to affect a dimensional change without prior approvalof the Engineer. Base metal and weld metal that issharply bent or kinked shall be rejected and replaced.

12.13 Tack Welds and Temporary Welds

12.13.1 Tack Welds

12.13.1.1 Location. All tack welds used in assemblyshall be located within the joint unless otherwiseapproved by the Engineer.

12.13.1.2 Requirements. All tack welds shall meetthe requirements of Table 12.2, or shall be removed asdescribed in 12.13.3.

12.13.2 Temporary Welds. All welds not shown as per-manent welds on the drawings or approved by the Engi-neer shall be removed as described in 12.13.3.

12.13.3 Weld Removal. When required, weld removalshall include all of the weld plus 3 mm [1/8 in] of theadjacent base metal to remove the HAZ. Weld and basemetal removal sites shall be faired to adjacent surfaceson a slope not steeper than 1 into the metal to 10 alongthe surface. The surface roughness shall not exceed 3 µm[125 µin].

12.14 Preheat and Interpass Temperature Control

Preheat and interpass temperature control shall be asspecified in 4.2. The minimum preheat and interpasstemperature for AASHTO M270M [M270] (ASTMA 709M [A 709]) Grade 250 [36], 345 [50], 345W

[50W], HPS 345W [HPS 50W], and Grade HPS 485W[HPS 70W] steels shall be as described in Tables 12.3and 12.4. The minimum and maximum preheat tempera-tures for Grades 690/690W [100/100W] steels shall be asdescribed in Table 12.5. For Grade HPS 485W [HPS70W], the maximum preheat and interpass temperatureshall be 230°C [450°F] for all thicknesses.

12.15 Postweld Thermal Treatments

12.15.1 Hydrogen Diffusion Postheat. Hydrogen diffu-sion postheat shall be required when specified in the con-tract documents, WPS, repair procedure, or whenrequired by the Engineer to prevent cracking or minimizelamellar tearing.

12.15.1.1 Minimum Temperature Prior to Hydro-gen Diffusion Postheat. When hydrogen diffusionpostheat is required, the weld shall not be allowed to coolbelow the minimum preheat and interpass temperaturebefore being raised to the hydrogen diffusion postweldheat treatment (PWHT) temperature.

12.15.1.2 Hydrogen Diffusion Postheat Tempera-ture Limitations. When hydrogen diffusion postheat isrequired, welds and adjacent base metal shall be heatedto a temperature of 230°C [450°F] minimum to 315°C[600°F] maximum for not less than one hour for each25 mm [1 in] of weld thickness, or two hours, whicheveris less. The minimum heating time for repair welds shallbe one hour for each 25 mm [1 in] of repair weld depthfrom the surface, but not less than one hour. Longer heat-ing periods may be used.

12.15.2 Postweld Heat Treatment (PWHT). Any heat-ing of welds or base metal by sources other than thewelding arc to temperatures in excess of 480°C [900°F]except for brief periods required for approved heat curv-ing, cambering and straightening, shall be consideredPWHT.

12.15.2.1 Approval. All PWHT shall be approved bythe Engineer.

12.15.2.2 Controls. PWHT shall be completelydescribed giving details of minimum and maximum tem-perature, maximum heating and cooling rates, minimumand maximum time at specified temperatures and allother details necessary to control the heat treatment.

12.15.2.3 Testing. Tests shall be performed to deter-mine the effects of the proposed heat treatment on thestrength, ductility, and toughness of welds and basemetal before heating. The Engineer may accept recordsof previous qualification tests in lieu of testing. MT and


191

UT, when required, shall be repeated or performed afterthe weldment has cooled to ambient temperature.

12.16 Weld InspectionAll welds, including repair welds, shall be inspected asrequired by Clause 6 and shall meet the additionalrequirements of this FCP.

12.16.1 QA/QC. The Engineer shall provide QA inspec-tion as necessary to verify the proper and sufficientimplementation of this FCP and applicable provisions ofthe contract documents. QA inspection by the Engineershall not relieve the Contractor from the responsibility toconform to all requirements of the contract documents,including the requirement to provide QC inspection andtests as described in Clause 6 and this FCP.

12.16.1.1 Inspectors. Inspectors shall be qualified asspecified in 6.1.3. Lead QC and QA Inspectors shallhave a minimum of three years experience in steel bridgefabrication inspection. A lead inspector shall be definedas the leader of the QA or QC inspection team at a spe-cific work location, one who assigns other inspectors asnecessary and supervises their work. The lead inspectorshall be familiar with and shall have seen each FCM thathe or she has inspection responsibility for and mayaccept as described in 12.16.5.2. All inspectors shallhave the authority to accept or reject materials and work-manship subject to review by the lead inspector.

12.16.1.2 NDT Technicians. NDT technicians shallbe certified to Level II or certified to Level III and quali-fied to perform as a Level II in conformance withASNT’s Recommended Practice SNT-TC-1A. Level IItechnicians shall be supervised by an individual certifiedto Level III. Level III individuals shall possess a cur-rently valid ASNT Level III certificate. The Engineermay accept alternative qualifications which are deemedequivalent.

12.16.2 Type of Weld and NDT Required

12.16.2.1 Tension and Repaired Welds in ButtJoints. Butt joints in tension and repaired groove weldsin butt joints shall be QC inspected by both RT and UT.

12.16.2.2 T- and Corner Joint Tension and Re-paired Groove Welds. All tension and repaired groovewelds in T- and corner joints shall be QC inspected byUT.

12.16.2.3 Fillet Weld Repairs. Fillet weld repairsshall be inspected by MT. The test length shall include100% of the length of the repair, and, when appropriate,at least 300 mm [12 in] beyond the ends of each repairweld.

12.16.3 RT Requirements. RT shall be done using hole-type IQIs as described in Table 6.1 and Figure 6.1E.

12.16.4 Cooling Times Prior to Inspection. RT andpreliminary visual inspections may be performed as soonas welds have cooled. UT, MT, and final visual inspec-tion shall be done after the welds have cooled to ambienttemperature for at least the following minimum timeperiods:

(1) Fillet welds on steel with a minimum specifiedyield strength of 345 MPa [50 ksi] or less, 24 hours.

(2) Fillet welds on steel with a minimum specifiedyield strength greater than 345 MPa [50 ksi], 48 hours.

(3) Groove welds in steel with a minimum specifiedyield strength of 345 MPa [50 ksi] or less; 24 hours whenthe weld depth is 50 mm [2 in] or less, and 48 hourswhen the weld depth is greater than 50 mm [2 in].

(4) Groove welds in steel with a minimum specifiedyield strength greater than 345 MPa [50 ksi]; 48 hourswhen the weld depth is 50 mm [2 in] or less and 72 hourswhen the weld depth is greater than 50 mm [2 in].

12.16.5 Inspection and Record Keeping

12.16.5.1 Certified Reports. Certified copies of milltest reports, visual and NDT inspection reports, radio-graphs and other documentation that materials and work-manship conform to the requirements of the contractdocuments shall be available for examination and shallbe included in the permanent record. All fracture-criticalbase metal shall be identified with a specific mill testreport. Heat and mill test report identity shall be main-tained when base metal is cut for use in other FCMs. Allrepairs requiring documentation as described in 12.17.3shall be recorded in the inspection records. The inspec-tion record of each fracture critical erection piece shallbe identified by the erection mark specified in the shopdrawings.

12.16.5.2 Identification of Inspectors. All Contrac-tor (QC) and Engineer (QA) inspectors that haveinspected FCMs shall be identified in the inspectionrecords. The QC and QA Lead Inspectors that haveinspected the FCM, reviewed the inspection records andperformance of assistant inspectors, and determined thatthe FCM meets the requirements of this FCP and thecontract documents shall sign and date the inspectionrecord noting their acceptance.

12.16.5.3 Recording Discontinuities Found by UT.All discontinuities found by UT must be recorded on theNDT report if required in 6.19.8.


192

12.17 Repair WeldingRepair welding shall be defined as any welding, includ-ing removal of weld or base metal in preparation forwelding, necessary to correct unacceptable discontinui-ties in materials or workmanship. Welded repairs shallbe categorized as noncritical (see 12.17.2) or critical (see12.17.3), with separate requirements for each.

12.17.1 WPS Requirements. Repair welding shall bedone in conformance with an approved WPS. The WPSmay be preapproved as described in 12.17.2, or individu-ally approved as described in 12.17.3.

12.17.1.1 Approval Procedure. The Contractor mayprepare procedures and specifications for the repair ofanticipated routine problems and submit them to theEngineer for approval before beginning the work. TheContractor may use preapproved repair WPSs as soon asthe QA inspector has verified the discontinuity to berepaired is covered by the WPS.

12.17.1.2 Drawings. Repair WPSs shall includesketches, or full-size drawings, as necessary to describethe unacceptable discontinuity and the proposed methodof repair. WPSs for critical repairs described in 12.17.3shall document the location of the unacceptable disconti-nuities to be repaired.

12.17.1.3 Location. Unacceptable discontinuities tobe repaired shall be shown in plan view, elevation, andsection as necessary to describe the discontinuity prior torepair. The drawings shall be revised, if necessary, at thecompletion of repairs to document differences betweenthe presumed initial type, size, orientation, and locationof the unacceptable discontinuity and the final completedescription of the unacceptable discontinuity as observedand measured during repair.

12.17.2 Noncritical Repair Welds. Noncritical repairwelds are generally welds to deposit additional weldbeads or layers to compensate for insufficient weld sizeand to fill limited excavations to remove unacceptableedge or surface discontinuities, rollover or undercut,including:

(1) Gouges in cut edges that are 10 mm [3/8 in] deep,or less.

(2) Laminar discontinuities less than 25 mm (1 in]deep, or with a depth less than one-half the thickness ofthe cut edge, whichever is less, provided the discontinu-ity is not within 300 mm (12 in] of a butt joint loaded intension. Repair shall be made by excavating from the cutedge.

(3) Repair of base-metal surfaces as provided inAASHTO M160 [M160M] (ASTM A 6 [A 6M]).

(4) First-time excavation and repair from one side ofgroove welds and fillet welds which contain unaccept-able porosity, slag and fusion discontinuities, providedthe excavations do not exceed the following limits:

Length of Weld “L” Length of Excavation

Up to 0.5 m [1-1/2 ft].................... L or 250 mm [10 in],whichever is less

Over 0.5 m [1-1/2 ft] to1.0 m [3 ft] .................................... 300 mm [1 ft]

Over 1.0 m [3 ft] to 2.0 m [6 ft].... 450 mm [1-1/2 ft]

Over 2.0 m [6 ft] to 4.0 m [12 ft].. 600 mm [2 ft]

Over 4.0 m [12 ft] to 8.0 m [24 ft] 900 mm [3 ft]

Over 8.0 m [24 ft] ......................... 900 mm [3 ft] or10% L, whichever isgreater

The depth of groove weld excavation shall not exceed65% of the weld size shown on the drawings.

(5) Repairs to cracks confined to root passes discov-ered and corrected before depositing subsequent weldpasses.

(6) Repairs to ends of members where there is nodeadload or liveload stress.

(7) Deposition of weld metal up to 10 mm [3/8 in]deep, or 1/4 the base-metal thickness, whichever is less,to correct for length or joint geometry.

(8) Except as required by 12.15, PWHT shall not berequired, unless the excavation is greater than 12 mm[1/2 in] deep.

12.17.2.1 Noncritical Repair Procedures. Provisionshall be made for the preapproval and use of noncriticalrepair procedures and WPSs to ensure that the Contractorhas an acceptable plan for routine repairs prior to begin-ning the work.

12.17.3 Critical Weld Repairs. Except as provided in12.17.2, all welded repairs shall be considered critical.They include, but are not limited to the following:

(1) Repair of gouges in cut edges greater than 10 mm[3/8 in] deep.

(2) Repair of laminar discontinuities, except as pro-vided in 12.17.2(2). Repair may be made from the cutedge, or from a surface, as approved by the Engineer.

(3) Repair of surface or internal discontinuities inrolled, forged, and cast products not covered by12.17.2(3).


193

(4) Repair of cracks in base metal and welds includ-ing lamellar tears except as provided in 12.17.2(5).

(5) Corrections requiring weld removal and reweld-ing except as provided in 12.17.2(4).

(6) All welding to correct errors in fabrication suchas improper cutting, punching, drilling, machining,assembly, etc.

12.17.4 Approval. All critical repairs to base metal andwelds shall be approved by the Engineer prior to begin-ning the repair and shall be documented giving details ofthe type of discontinuity and extent of repair.

12.17.5 QA/QC Inspection. All repair welding shall besubject to QC and QA inspection.

12.17.6 Repair Procedure Minimum Provisions.Except that noncritical repairs described in 12.17.2 neednot be recorded, all repair WPSs shall include at least thefollowing provisions described in the order in which thework will be performed:

(1) Surfaces shall be cleaned as necessary to facilitatevisual inspection and NDT so that QC and QA inspectorscan accurately characterize the discontinuity(ies) of con-cern. Surfaces shall be ground when necessary to facili-tate visual inspection and NDT.

(2) Unacceptable discontinuities to be repaired shallbe recorded as required by 12.17.1.3, and in addition, thelocation of the excavation and proposed repair to edges,ends, holes, welds and other details of the FCM shall beshown.

(3) The preheating temperature prior to air carbon arcgouging shall be described in the WPS. Preheat for goug-ing shall not be less than 65°C [150°F].

(4) The method and extent of excavation to removeunacceptable weld and base metal discontinuities shallbe completely described, and, when appropriate, shallinclude the sequence of progressive excavations.

(5) MT and other NDT, if ordered by the Engineer,shall be used to verify that all of the unacceptable discon-tinuity is removed.

(6) All thermal cut and gouged surfaces that shall bewelded upon shall be ground to produce a smooth, brightsurface. Oxygen gouging shall be prohibited.

(7) All temporary weld extensions and steel backing,including the method of attachment, shall be shown indetail.

(8) Preheat and interpass temperature controls shallbe listed. They shall meet, or exceed, the following mini-mum requirements:

(a) All steels with a minimum specified yieldstrength of 485 MPa [70 ksi] or less, in thicknesses up to40 mm [1-1/2 in] inclusive, shall have a minimum pre-heat and interpass temperature of 160°C [325°F]. Forthicknesses greater than 40 mm [1-1/2 in], the minimumpreheat and interpass temperature shall be 200°C[400°F].

(b) Grade 690/690W [100/100W] steels shallhave a preheat and interpass temperature that conformsto the requirements of Table 12.5 for the heat input used,except that the minimum temperature shall be 110°C[225°F]. Care shall be taken when welding Grade 690/690W [100/100W] steels to ensure that the combinedpreheat or interpass temperature plus welding heat inputdoes not exceed the manufacturer’s recommendations.

(9) Welding shall be done as described in theapproved repair procedure. WPSs qualified for weldingof FCMs need not be requalified for repair welding, pro-vided the joint detail used allows access for welding.

(10) Peening, if required, shall be listed in the repairprocedure and shall conform to the requirements of 3.8.Any additional requirements shall be completelydescribed.

(11) All repair welds in groove excavations shall bepostheated as described in 12.15. Other weld repairs,such as repair or replacement of fillet welds and weldingof shallow excavations described in 12.17.2, shallbe postheated when ordered by the Engineer. Postheat-ing, when required, shall be as described in the repairprocedure.

(12) Repaired surfaces shall be ground flush withadjacent base metal or weld surfaces, or finished withslight reinforcement that is faired to adjoining surfaces asapproved by the Engineer.

(13) PWHT, when required, shall be described in therepair procedure and shall conform to the requirementsof 12.15.

194


Table 12.1CVN Test Values of Weld Metal with Matching Strength (see 12.6.4.1)

M270M [M270] Steel(A 709M [A 709]), Grades as Noted

Minimum CVN Test Energy,J [ft∙lb] Test Temperature

250 [36]345 [50]345W [50W]HPS 485W [HPS 70W]690/690W [100/100W]

34 [25]34 [25]34 [25]41 [30]48 [35]

–30°C [–20°F]–30°C [–20°F]–30°C [–20°F]–30°C [–20°F]–35°C [–30°F]

Table 12.2Tack Weld Requirements (see 12.13.1.2)

Type WPS Required? Minimum Size Minimum Length Minimum Preheat Notes

Remelted by SAW No None None None a, b

Covered bynon-SAW

Yes Table 2.1 or 2.2 75 mm [3 in] Table 12.3, 12.4, or 12.5

Tack weldsoutside joint

Yes Table 2.1 or 2.2 75 mm [3 in] Table 12.3, 12.4, or 12.5

c

Tack welds <75 mm [3 in] long, or smaller than Table 2.1 or 2.2

Yes None None 200°C [400°F]

a GMAW may be used for tack welding without the Engineer’s approval.b SMAW electrodes shall meet the requirements of 12.6.2.c Tack welds outside the joint shall require the Engineer’s approval (see 12.13.1.1).

Note: Filler metals listed in Table 4.1 or 4.2 shall be used.

195


Table 12.3M270M [M270] (A 709M [A 709]) Gr. 250 [36], 345 [50] Minimum

Preheat and Interpass Temperatures, °C [°F] (see 12.14)

Heat Input (as calculated by 5.12) kJ/mm [kJ/in]

1.2 [30] < HI ≤ 2.0 [50] 2.0 [50] < HI ≤ 2.8 [70] HI > 2.8 [70]

Thickness t, mm [in] H4 H8 H16 H4 H8 H16 H4 H8 H16

t ≤ 20 [3/4] 40 [125] 60 [150] 100 [200] 40 [100] 40 [100] 60 [150] 40 [100] 40 [100] 40 [100]

20 [3/4] < t ≤ 40 [1-1/2] 60 [150] 100 [200] 100 [225] 60 [100] 65 [150] 100 [200] 40 [100] 60 [100] 80 [200]

40 [1-1/2] < t ≤ 60 [2-1/2] 100 [200] 120 [225] 120 [270] 80 [150] 100 [200] 120 [225] 60 [100] 80 [150] 80 [200]

t > 60 [2-1/2] 140 [300] 160 [325] 180 [350] 140 [275] 140 [300] 160 [325] 120 [250] 140 [275] 140 [300]

Note: H4, H8, and H16 are electrode optional supplemental designators for diffusible hydrogen.

Table 12.4M270M [M270] (A 709M [A 709]) Gr. 345W [50W], HPS 345W [HPS 50W], HPS 485W

[HPS 70W] Minimum Preheat and Interpass Temperatures, °C [°F] (see 12.14)


1.2 [30] < HI ≤ 2.0 [50] 2.0 [50] < HI ≤ 2.8 [70] HI > 2.8 [70]

Thickness t, mm [in] H4 H8 H16 H4 H8 H16 H4 H8 H16

t ≤ 20 [3/4] 40 [125] 60 [150] 80 [200] 40 [100] 40 [100] 60 [150] 40 [100] 40 [100] 40 [100]

20 [3/4] < t ≤ 40 [1-1/2] 100 [200] 100 [250] 120 [275] 80 [175] 100 [200] 120 [250] 60 [150] 80 [175] 100 [200]

40 [1-1/2] < t ≤ 60 [2-1/2] 140 [300] 160 [325] 180 [350] 140 [275] 140 [300] 160 [325] 120 [250] 140 [275] 160 [300]

t > 60 [2-1/2] 180 [350] 180 [350] 200 [375] 160 [325] 180 [350] 200 [350] 140 [300] 160 [325] 180 [350]

Note: H4, H8, and H16 are electrode optional supplemental designators for diffusible hydrogen.

Table 12.5M270M [M270] (A 709M [A 709]) Gr. 690 [100], 690W [100W] Minimum

and Maximum Preheat/Interpass Temperature, °C [°F] (see 12.14)

Thickness t, mm [in]


1.2 [30] ≤ HI< 1.6 [40]

1.6 [40] ≤ HI< 2.0 [50]

2.0 [50] ≤ HI< 2.8 [70]

2.8 [70] ≤ HI< 3.6 [90] 3.6 [90] ≤ HI

6 [1/4] ≤ t ≤ 10 [3/8] 40–60 [100–150] — — — —

10 [3/8] < t ≤ 13 [1/2] 60–160 [150–300] 40–100 [100–200] — — —

13 [1/2] < t ≤ 20 [3/4] 120–200 [250–400] 100–180 [200–350] 40–120 [100–250] — —

20 [3/4]< t ≤ 25 [1] — 120–200 [250–400] 120–200 [250–400] 60–160 [150–300] —

25 [1] < t ≤ 50 [2] — — 120–200 [250–400] 120–200 [250–400] 100–180 [200–350]

t > 50 [2] — — 150–240 [300–450] 140–240 [300–450] 140–240 [300–450]

Note: The table applies to electrodes with the H4 or H8 optional supplemental designator for diffusible hydrogen limits.


196



197

Normative Information

These annexes contain information and requirements that are considered part of the standard.

Annex A Effective Throat

Annex B Effective Throats of Fillet and Skewed T-Joints

Annex C Flatness of Girder Webs—Bridges

Annex D Terms and Definitions

Annex E Manufacturer’s Stud Base Qualification Requirements

Annex F Part A—Qualification and Calibration of the UT Unit with Other Approved Reference BlocksPart B—UT Equipment Qualification Procedures

Annex G Guidelines on Alternative Methods for Determining Preheat

Annex H Welding Requirements for Conventional, Nonfracture Critical A709M [A709] HPS 485W [HPS 70W]Components with Reduced Preheat and Interpass Temperature

Informative Information

These annexes are not considered part of the standard and are provided for informational purposes.

Annex I Weld Quality Requirements for Tension Joints

Annex J Description of Common Weld and Base Metal Discontinuities

Annex K Short Circuiting Transfer

Annex L Suggested Sample Welding Forms

Annex M Guidelines for Preparation of Technical Inquiries to the Joint AASHTO/AWS Subcommittee on BridgeWelding

Annex N Reference Documents

Annexes

ANNEXES AASHTO/AWS D1.5M/D1.5:2008

198

Cross Reference for Renumbered Annexes from the 2002 Code to the 2008 Code

Location in2002 Code

Location in2008 Code

Annex I Effective Throat Annex A

Annex II Effective Throat of Fillet Welds in Skewed T-Joints Annex B

Annex III Suggested Sample Forms Annex L

Annex IV Flatness of Girder Webs—Bridges Annex C

Annex V Terms and Definitions Annex D

Annex VI Manufacturer’s Stud Base Qualification Requirements Annex E

Annex VII Part A—Qualification and Calibration of the UT Unit with Other Approved Reference Part A—BlocksPart B—UT Equipment Qualification Procedures

Annex F

Annex VIII Guidelines on Alternative Methods for Determining Preheat Annex G

New Annex Welding Requirements for Conventional, Nonfracture Critical A709M [A709] HPS 485W [HPS 70W] Components with Reduced Preheat and Interpass Temperature

Annex H

Annex A Weld Quality Requirements for Tension Joints Annex I

Annex B Description of Common Weld and Base Metal Discontinuities Annex J

Annex C Short Circuiting Transfer Annex K

Annex D Guidelines for Preparation of Technical Inquiries for the Joint AASHTO/AWS Subcommittee on Bridge Welding

Annex M

Annex E Reference Documents Annex N

Annex F Location of Section 9 Provisions of 1996 Edition in AASHTO/AWS D1.5M/D1.5:2002

Deleted


199

Annex A (Normative)

Effective Throat

This annex is part of AASHTO/AWS D1.5M/D1.5:2008, Bridge Welding Code,and includes mandatory elements for use with this standard.

Note: The effective throat of a weld is the minimum distance from the root of the joint to its face, with or without a deduction of 3 mm[1/8 in] as required by 2.3.1.3, less any convexity.



200


201

Table B.1 is a tabulation showing equivalent leg size fac-tors for a range of dihedral angles between 60° and 135°,assuming there is no root opening. Root opening(s)2 mm [1/16 in] or greater, but not exceeding 5 mm[3/16 in], shall be added directly to the leg size. The re-quired leg size for fillet welds in skewed joints shall becalculated using the equivalent leg size factor for correctdihedral angle, as shown in the example.

Example(SI Units)

Given: Skewed T-joint, angle: 75°; root opening:2 mm [1/16 in]

Required: Strength equivalent to 90° fillet weld ofsize: 8 mm [5/16 in]

Procedure: (1) Factor for 75° from Table B.1: 0.86(2) Equivalent leg size, w, of skewed joint, without

root opening:w = 0.86 × 8 = 6.9 mm [1/4 in]

(3) With root opening of: 2.0 mm [5/64 in](4) Required leg size, w, of 8.9 mm [21/64 inskewed fillet weld: [(2) + (3)]

(5) Rounding up to a practical dimension:w = 9.0 mm [5/16 in]

For fillet welds having equal measured legs (wn), the dis-tance from the root of the joint to the face of the diagram-matic weld (tn) may be calculated as follows:

For root openings >2 mm [1/16 in] and ≤5 mm[3/16 in], use

For root openings <2 mm [1/16 in], use

where the measured leg of such fillet weld (wn) is theperpendicular distance from the surface of the joint to theopposite toe, and (R) is the root opening, if any, betweenparts (see Figure 2.3). Acceptable root openings aredefined in 3.3.1.

tnwn Rn–

2 sinΨ2----

-------------------=

Rn 0 and t'n tn= =

Annex B (Normative)

Effective Throats of Fillet Welds in Skewed T-Joints


ANNEX B AASHTO/AWS D1.5M/D1.5:2008

202

Table B.1Equivalent Fillet Weld Leg Size Factors for Skewed T-Joints, R = 0

Dihedral angle, Ψ 60° 65° 70° 75° 80° 85° 90° 95°

Comparable fillet weld size for same strength

0.71 0.76 0.81 0.86 0.91 0.96 1.00 1.03

Dihedral angle, Ψ 100° 105° 110° 115° 120° 125° 130° 135°

Comparable fillet weld size for same strength

1.08 1.12 1.16 1.19 1.23 1.25 1.28 1.31


203

Notes:1. D = Depth of web.2. d = Least panel dimension.

Annex C (Normative)

Flatness of Girder Webs—Bridges


ANNEX C AASHTO/AWS D1.5M/D1.5:2008

204

DIMENSIONS IN MILLIMETERS

Intermediate Stiffener on Both Sides of Web—Fascia Girders

Thickness of Web, mm

Depth ofWeb, mm Least Panel Dimension, mm

8Less then 12001200 and over

780630

1040840 1050 1260 1470 1680 1890 2100 2310 2520 2730 2940

9Less than 13501350 and over

780630

1040840

13001050 1260 1470 1680 1890 2100 2310 2520 2730 2940


780630

1040840

13001050 1260 1470 1680 1890 2100 2310 2520 2730 2940


780630

1040840

13001050

15601260 1470 1680 1890 2100 2310 2520 2730 2940


780630

1040840

13001050

15601260 1470 1680 1890 2100 2310 2520 2730 2940


780630

1040840

13001050

15601260

18201470

20801680 1890 2100 2310 2520 2730 2940


780630

1040840

13001050

15601260

18201470

20801680

23401890 2100 2310 2520 2730 2940

Maximum Allowable Variation, mm

6 8 10 12 14 16 18 20 22 24 26 28

Intermediate Stiffeners on One Side of Web Only—Fascia Girders




720480 640 800 960 1120 1280 1440 1600 1760 1920 2080 2240


720480 640 800 960 1120 1280 1440 1600 1760 1920 2080 2240


720480

960640 800 960 1120 1280 1440 1600 1760 1920 2080 2240


720480

960640 800 960 1120 1280 1440 1600 1760 1920 2080 2240


720480

960640

1200800 960 1120 1280 1440 1600 1760 1920 2080 2240


720480

960640

1200800 960 1120 1280 1440 1600 1760 1920 2080 2240


720480

960640

1200800

1440960 1120 1280 1440 1600 1760 1920 2080 2240


6 8 10 12 14 16 18 20 22 24 26 28

AASHTO/AWS D1.5M/D1.5:2008 ANNEX C

205

DIMENSIONS IN MILLIMETERS

Intermediate Stiffeners on Both Sides of Web—Interior Girders




690550

920740

1150920 1100 1290 1470 1660 1840 2020 2210 2390 2580


690550

920740

1150920 1100 1290 1470 1660 1840 2020 2210 2390 2580


690550

920740

1150920

13801100 1290 1470 1660 1840 2020 2210 2390 2580


690550

920740

1150920

13801100

16101290 1470 1660 1840 2020 2210 2390 2580


690550

920740

1150920

13801100

16101290 1470 1660 1840 2020 2210 2390 2580


690550

920740

1150920

13801100

16101290

18401470

20701660 1840 2020 2210 2390 2580


690550

920740

1150920

13801100

16101290

18401470

20701660

23001840 2020 2210 2390 2580


6 8 10 12 14 16 18 20 22 24 26 28

Intermediate Stiffeners on One Side Only of Web—Interior Girders




600400

800540 670 800 940 1070 1210 1340 1470 1610 1740 1880


600400

800540 670 800 940 1070 1210 1340 1470 1610 1740 1880


600400

800540

1000670 800 940 1070 1210 1340 1470 1610 1740 1880


600400

800540

1000670 800 940 1070 1210 1340 1470 1610 1740 1880


600400

800540

1000670

1200800 940 1070 1210 1340 1470 1610 1740 1880


600400

800540

1000670

1200800

1400940 1070 1210 1340 1470 1610 1740 1880


600400

800540

1000670

1200800

1400940

16001070 1210 1340 1470 1610 1740 1880


6 8 10 12 14 16 18 20 22 24 26 28

No Intermediate Stiffeners—Interior and Fascia Girders

Thickness of Web, mm Least Panel Dimension, mm

Any 900 1200 1500 1800 2100 2400 2700 3000 3300 3600 3900 4200


6 8 10 12 14 16 18 20 22 24 26 28

ANNEX C AASHTO/AWS D1.5M/D1.5:2008

206

DIMENSIONS IN INCHES

Intermediate Stiffeners on One Side Only of Web, Interior Girders

Thickness of Web, in

Depth ofWeb, in Least Panel Dimension, in

5/16Less than 3131 and over

2517

3121 25 29 34 38 42 46 50 54 59 63 67 71


2517

3121

3825 29 34 38 42 46 50 54 59 63 67 71


2517

3121

3825

4429 34 38 42 46 50 54 59 63 67 71


2517

3121

3825

4429

5034 38 42 46 50 54 59 63 67 71


2517

3121

3825

4429

5034

5638 42 46 50 54 59 63 67 71


2517

3121

3825

4429

5034

5638

6342 46 50 54 59 63 67 71

Maximum Allowable Variation, in

1/4 5/16 3/8 7/16 1/2 9/16 5/8 11/16 3/4 13/16 7/8 15/16 1 1-1/16

Note: For actual dimensions not shown, use the next higher figure.

Intermediate Stiffeners on Both Sides of Web, Interior Girders




2923

3629

4335

5040 46 52 58 63 69 75 81 86 92 98


2923

3629

4335

5040

5846 52 58 63 69 75 81 86 92 98


2923

3629

4335

5040

5846

6552 58 63 69 75 81 86 92 98


2923

3629

4335

5040

5846

6552

7258

7963 69 75 81 86 92 98


2923

3629

4335

5040

5846

6552

7258

7963

8669 75 81 86 92 98


2923

3629

4335

5040

5846

6552

7258

7963

8669

9375 81 86 92 98


1/4 5/16 3/8 7/16 1/2 9/16 5/8 11/16 3/4 13/16 7/8 15/16 1 1-1/16


AASHTO/AWS D1.5M/D1.5:2008 ANNEX C

207

DIMENSIONS IN INCHES

Intermediate Stiffeners on One Side Only of Web, Fascia Girders




3020

3825 30 35 40 45 50 55 60 65 70 75 80 85


3020

3825 30 35 40 45 50 55 60 65 70 75 80 85


3020

3825

4530 35 40 45 50 55 60 65 70 75 80 85


3020

3825

4530

5335 40 45 50 55 60 65 70 75 80 85


3020

3825

4530

5335

6040 45 50 55 60 65 70 75 80 85


3020

3825

4530

5335

6040

6845 50 55 60 65 70 75 80 85


1/4 5/16 3/8 7/16 1/2 9/16 5/8 11/16 3/4 13/16 7/8 15/16 1 1-1/16


Intermediate Stiffeners on Both Sides of Web, Fascia Girders




3326

4133

4939 46 53 59 66 72 79 85 92 98 105 112


3326

4133

4939

5746 53 59 66 72 79 85 92 98 105 112


3326

4133

4939

5746

6553

7359 66 72 79 85 92 98 105 112


3326

4133

4939

5746

6553

7359

8166 72 79 85 92 98 105 112


3326

4133

4939

5746

6553

7359

8166

8972 79 85 92 98 105 112


3326

4133

4939

5746

6553

7359

8166

8972

9879 85 92 98 105 112


1/4 5/16 3/8 7/16 1/2 9/16 5/8 11/16 3/4 13/16 7/8 15/16 1 1-1/16


No Intermediate Stiffeners, Interior or Fascia Girders

Thickness of Web, in Depth of Web, in

Any 38 47 56 66 75 84 94 103 113 122 131 141 150 159 169 178 188


1/4 5/16 3/8 7/16 1/2 9/16 5/8 11/16 3/4 13/16 7/8 15/16 1 1-1/16 1-1/8 1-3/16 1-1/4



208


209

A*active flux (SAW). A flux which contains small

amounts of manganese or silicon, or both, added toimprove the weld in certain single pass applications.Change in arc voltage or the number of weld passesmay significantly change weld metal chemistry andmechanical properties.

*alloy flux (SAW). A flux which contains alloy ingredi-ents intended to modify the weld metal chemistry.Changes in arc voltage may significantly change weldmetal chemistry.

*all-weld-metal test specimen. A test specimen with thereduced section composed wholly of weld metal.

amplitude length rejection level (UT). The maximumlength of discontinuity allowed by various indicationratings associated with weld size, as indicated in Ta-bles 6.3 and 6.4.

arc gouging. Thermal gouging that uses an arc cuttingprocess variation used to form a bevel or groove.

as-welded. Pertaining to the condition of weld metal,welded joints, and weldments after welding, but priorto any subsequent thermal, mechanical, or chemicaltreatments.

attenuation (UT). The loss in acoustic energy whichoccurs between any two points of travel. This lossmay be due to absorption, reflection, etc. (In thiscode, using the shear wave pulse-echo method of test-

ing, the attenuation factor is 2 dB per 25 mm [1 in] ofsound path distance after the first 25 mm [1 in].)

automatic welding. Welding with equipment that re-quires only occasional or no observation of the weld-ing and no manual adjustment of the equipmentcontrols. See also machine welding.

Bbackgouging. The removal of weld metal and base metal

from the weld root side of a welded joint to facilitatecomplete fusion and CJP upon subsequent weldingfrom that side.

backing. A material or device placed against the backside of the joint, or at both sides of a weld in ESW andEGW, to support and retain molten weld metal. Thematerial may be partially fused or remain unfusedduring welding and may be either metal or nonmetal.

backing pass. A weld pass made for a backing weld.

backing ring. Backing in the form of a ring, generallyused in the welding of pipe.

backing weld. Backing in the form of a weld.

back weld. A weld made at the back of a single-grooveweld.

base metal. The metal or alloy to be welded, brazed, sol-dered, or cut.

Annex D (Normative)

Terms and Definitions


The terms and definitions in this glossary are divided into three categories: (1) general welding terms compiled by theAWS Committee on Definitions and Symbols, (2) terms, defined by the AWS Structural Welding Committee, whichapply only to ultrasonic testing, designated by (UT) following the term, and (3) other terms, preceded by asterisks,which are defined as they relate to this code.

ANNEX D AASHTO/AWS D1.5M/D1.5:2008

210

bevel angle. The angle between the bevel of a jointmember and a plane perpendicular to the surface ofthe member.

boxing. The continuation of a fillet weld around a cornerof a member as an extension of the principal weld.

butt joint. A joint between two members aligned ap-proximately in the same plane.

butt weld. A nonstandard term for a weld in a butt joint.See butt joint.

C*caulking. Plastic deformation of weld and base-metal

surfaces by mechanical means to seal or obscurediscontinuities.

CJP (complete joint penetration). A joint root condi-tion in a groove weld in which weld metal extendsthrough the joint thickness.

*CJP (complete joint penetration) groove weld. Agroove weld which has been made from both sides orfrom one side on a backing having complete penetra-tion and fusion of weld and base metal throughout thedepth of the joint.

complete fusion. Fusion over the entire fusion faces andbetween all adjoining weld beads.

*consumable guide ESW or EGW. An electroslag orelectrogas welding process variation in which fillermetal is supplied by an electrode(s) and the guidingmember(s).

continuous weld. A weld that extends continuouslyfrom one end of a joint to the other. Where the joint isessentially circular, it extends completely around thejoint.

corner joint. A joint between two members located ap-proximately at right angles to each other.

crater. A depression in the weld face at the terminationof a weld bead.

CVN. Charpy V-notch.

Ddecibel (dB) (UT). The logarithmic expression of a ratio

of two amplitudes or intensities of acoustic energy.

decibel rating (UT). See preferred term indicationrating.

defect. A discontinuity or discontinuities that by natureor accumulated effect (for example, total crack

length) render a part or product unable to meet mini-mum applicable acceptance standards or specifica-tions. This term designates rejectability. See alsodiscontinuity and flaw.

*defective weld. A weld containing one or more defects.

defect level (UT). See preferred term indication rating.

defect rating (UT). See preferred term indicationrating.

depth of fusion. The distance that fusion extends intothe base metal or previous bead from the surfacemelted during welding.

discontinuity. An interruption of the typical structure ofa material, such as a lack of homogeneity in its me-chanical, metallurgical, or physical characteristics. Adiscontinuity is not necessarily a defect.

downhand. See preferred term flat welding position.

*drawings. As used in this code, refers to plans, design,detail drawings and erection plans.

E*effective length of weld. The length throughout which

the correctly proportioned cross section of the weldexists. In a curved weld, it shall be measured alongthe weld axis.

EGW (electrogas welding). An arc welding process thatuses an arc between a continuous filler metal elec-trode, and the weld pool, employing approximatelyvertical welding progression with backing to confinethe molten weld metal. The process is used with orwithout an externally supplied shielding gas and with-out the application of pressure.

ESW (electroslag welding). A welding process that pro-duces coalescence of metals with molten slag thatmelts the filler metal and the surfaces of the work-pieces. The weld pool is shielded by this slag whichmoves along the full cross section of the joint as weld-ing progresses. The process is initiated by an arc thatheats the slag. The arc is then extinguished by theconductive slag, which is kept molten by its resistanceto electric current passing between the electrode andthe workpieces.

Ffaying surface. The mating surface of a member that is

in contact with or in close proximity to another mem-ber to which it is to be joined.

AASHTO/AWS D1.5M/D1.5:2008 ANNEX D

211

FCAW (flux cored arc welding). An arc welding pro-cess that uses an arc between a continuous filler metalelectrode and the weld pool. The process is used withshielding gas from a flux contained within the tubularelectrode with or without additional shielding from anexternally supplied gas, and without the application ofpressure.

filler metal. The metal or alloy to be added in making awelded, brazed, or soldered joint.

fillet weld leg. The distance from the joint root to the toeof the fillet weld.

*flash. The material which is expelled or squeezed outaround the base of a stud weld.

*flat welding position. The welding position used toweld from the upper side of the joint when the face ofthe weld is approximately horizontal.

flaw. An undesirable discontinuity. See also defect anddiscontinuity.

*flux. A material used to hinder or prevent the formationof oxides and other undesirable substances in moltenmetal and on solid metal surfaces, and to dissolve orotherwise facilitate the removal of such substances.See also active flux and neutral flux.

fusion. The melting together of filler metal and basemetal or of base metal only, to produce a weld. Seealso depth of fusion.

*fusion-type discontinuity. Signifies slag inclusion, in-complete fusion, incomplete joint penetration, andsimilar discontinuities associated with fusion.

fusion zone. The area of base metal melted as deter-mined on the cross section of a weld.

G*gas pocket. A cavity caused by entrapped gas.

GMAW (gas metal arc welding). An arc welding pro-cess that uses an arc between a continuous filler metalelectrode and the weld pool. The process is used withshielding from an externally supplied gas and withoutthe application of pressure.

*GMAW-S (gas metal arc welding short circuit arc).A gas metal arc welding process variation in whichthe consumable electrode is deposited during repeatedshort circuits.

*gouging (thermal). The forming of a bevel or grooveby material removal. See also backgouging, arcgouging, and oxygen gouging.

groove angle. The total included angle of the groovebetween workpieces.

groove face. That surface of a joint member included inthe groove.

groove weld. A weld made in a groove between theworkpieces.

HHAZ (heat-affected zone). That portion of the base

metal with mechanical properties or microstructurethat have been altered by the heat of welding, brazing,soldering, or thermal cutting.

*horizontal welding position

fillet weld. The position in which welding is per-formed on the upper side of an approximately hori-zontal surface and against an approximately verticalsurface [see Figures 5.4 and 5.7(B)].

groove weld. The position of welding in which theweld axis lies in an approximately horizontal planeand the weld face lies in an approximately verticalplane [see Figures 5.5 and 5.6(B)].

horizontal reference line (UT). A horizontal line nearthe center of the ultrasonic test instrument scope towhich all echoes are adjusted for dB reading.

Iindication (UT). The signal displayed on the oscillo-

scope signifying the presence of a sound wave reflec-tor in the part being tested.

indication level (UT). The calibrated gain or attenuationcontrol reading obtained for a reference-line heightindication from a discontinuity.

indication rating (UT). The decibel reading in relationto the zero reference level after having been correctedfor sound attenuation.

intermittent weld. A weld in which the continuity isbroken by recurring unwelded spaces.

*interpass temperature (welding). In a multiple-passweld, the temperature of the weld before the next passis started.

*IQI (image quality indicator). A device whose imagein a radiograph is used to determine radiographicquality level. It is not intended for use in judgingthe size nor for establishing acceptance limits ofdiscontinuities.


212

Jjoint. The junction of members or the edges of members

that are to be joined or have been joined.

joint penetration. The distance the weld metal extends fromthe weld face into a joint, exclusive of reinforcement.

joint root. That portion of a joint to be welded where themembers approach closest to each other. In cross sec-tion, the joint root may be either a point, a line, or anarea.

*joint welding procedure. The materials and detailedmethods and practices employed in the welding of aparticular joint.

Llap joint. A joint between two overlapping members in

parallel planes.

*layer. A stratum of weld metal or surfacing material.The layer may consist of one or more weld beads laidside by side.

leg (UT). The path the shear wave travels in a straightline before being reflected by the opposite surface ofmaterial being tested. See sketch below for leg identi-fication. Note: Leg I plus leg II equals one V-path.

leg of a fillet weld. See fillet weld leg.

M*machine. To shape, plane, mill, saw, grind or otherwise

finish by machine-operated tools.

*machine welding. Welding with equipment which per-forms the welding operation under the constant obser-vation and control of a welding operator. Theequipment may or may not load and unload the work-pieces. See also automatic welding.

manual welding. Welding with the torch, gun, or elec-trode holder held and manipulated by hand. Acces-sory equipment, such as part motion devices andmanually controlled filler material feeders may beused. See automatic welding, machine welding, andsemiautomatic welding.

MT. Magnetic particle testing.

Nneutral flux (SAW). A flux that will not cause a signifi-

cant change in the weld metal composition when thereis a large change in the arc voltage.

node (UT). See preferred term leg.

O*overhead welding position. The position in which

welding is performed from the underside of the joint[see Figures 5.4, 5.5, 5.6(D), and 5.7(D)].

*overlap (fusion welding). The protrusion of weldmetal beyond the weld toe or weld root.

oxygen cutting (OC). A nonstandard term for oxyfuelgas cutting.

oxygen gouging. Thermal gouging that uses an oxygencutting process variation to form a bevel or groove.

P*parallel electrode. See SAW.

pass. See preferred term weld pass.

peening. The mechanical working of metals using im-pact blows.

*piping porosity (ESW and EGW). Elongated gaspores whose major dimension lie in a direction ap-proximately parallel to the weld axis which is verticalduring welding. When not controlled, piping porositycan be extensive, and very long pores or tunnels havebeen found in ESW welds. This defect is difficult toevaluate by UT.

*piping porosity (general). Elongated porosity whosemajor dimension lies in a direction approximatelynormal to the weld surface. (They generally grow ver-tically during welding before the weld metal has com-pletely solidified.) Piping porosity is frequentlyreferred to as pin holes when the porosity extends tothe weld surface.

PJP (partial joint penetration). Joint penetration that isintentionally less than complete.

plug weld. A weld made in a circular hole in one mem-ber of a joint, fusing that member to another member.A fillet-welded hole shall not be construed as con-forming to this definition.


213

*porosity. Cavity-type discontinuities formed by gas en-trapment during solidification.

*positioned weld. A weld made in a joint that has beenplaced to facilitate making the weld.

*postweld heat treatment. Any heat treatment afterwelding.

*preheating. The application of heat to the base metalimmediately before welding, brazing, soldering, ther-mal spraying, or cutting.

preheat temperature (welding). A specified tempera-ture that the base metal shall attain in the welding,brazing, soldering, thermal spraying, or cutting areaimmediately before these operations are performed.

procedure qualification. The demonstration that weldsmade by a specific procedure can meet prescribedstandards.

procedure qualification record (PQR) (welding). Adocument providing the actual welding variables usedto produce an acceptable test weld and the results oftests conducted on the weld to qualify a WPS. SeeForm E-1.

PT. Liquid penetrant testing.

Qqualification. See preferred terms welder performance

qualification and procedure qualification.

Rrandom sequence. A longitudinal sequence in which the

weld bead increments are made at random.

reference level (UT). The decibel reading obtained for ahorizontal reference-line height indication from a ref-erence reflector.

reference reflector (UT). The reflector of known geom-etry contained in the IIW reference block or otherapproved blocks.

reinforcement of weld. See weld reinforcement.

*rejectable discontinuity. See preferred term defect.

resolution (UT). The ability of UT equipment to give sep-arate indications from closely spaced reflectors.

root face. That portion of the groove face within thejoint root (see AWS A3.0, Figure 5).

root of joint. See joint root.

root of weld. See weld root.

root opening. The separation at the joint root betweenthe workpieces.

RT. Radiographic testing.

SSAW (submerged arc welding). An arc welding pro-

cess that uses an arc or arcs between a bare metalelectrode or electrodes and the weld pool. The arc andmolten metal are shielded by a blanket of granularflux on the workpieces. The process is used withoutpressure and with filler metal from the electrode andsometimes from a supplemental source (welding rod,flux, or metal granules).

*single electrode. One electrode connected exclu-sively to one power source which may consist of oneor more power units.

*parallel electrode. Two electrodes connected elec-trically in parallel and exclusively to the same powersource. Both electrodes are usually fed by means of asingle electrode feeder. Welding current, when speci-fied, is the total for the two electrodes.

*multiple electrodes. The combination of two ormore single or parallel electrode systems. Each of thecomponent systems has its own independent powersource and its own electrode feeder.

scanning level (UT). The dB setting used during scan-ning, as described in Tables 6.3 and 6.4.

*semiautomatic welding. Arc welding with equipmentthat controls only the filler metal feed. The advance ofthe welding is manually controlled.

shielding gas. Protective gas used to prevent or reduceatmospheric contamination.

*single-welded joint (fusion welding). In arc and gaswelding, any joint welded from one side only.

size of weld. See weld size.

slot weld. A weld made in an elongated hole in onemember of a joint fusing that member to anothermember. The hole may be open at one end. A filletwelded slot shall not be construed as conforming tothis definition.

SMAW (shielded metal arc welding). An arc weldingprocess with an arc between a covered metal electrodeand the weld pool. The process is used with shieldingfrom the decomposition of the electrode covering,without the application of pressure, and with fillermetal from the electrode.

sound beam distance (UT). See preferred term soundpath distance.


214

sound path distance (UT). The distance between thesearch unit test material interface and the reflector asmeasured along the centerline of the sound beam.

spatter. The metal particles expelled during fusion weld-ing that do not form a part of the weld.

stringer bead. A type of weld bead made without appre-ciable weaving motion.

*stud arc welding (SW). An arc welding process thatproduces coalescence of metals by heating them withan arc between a metal stud, or similar part, and theother workpiece. When the surfaces to be joined areproperly heated, they are brought together under pres-sure. Partial shielding may be obtained by the use of aceramic ferrule surrounding the stud. Shielding gas orflux may or may not be used.

*stud base. The stud tip at the welding end, includingflux and container or metal insert, and 3 mm [1/8 in]of the body of the stud adjacent to the tip.

Ttack weld. A weld made to hold parts of a weldment in

proper alignment until the final welds are made.

*tack welder. A fitter, or someone under the direction ofa fitter, who has been qualified to tack weld parts of aweldment to hold them in proper alignment until thefinal welds are made.

*tandem. Refers to a geometrical arrangement of elec-trodes in which a line through the arcs is parallel tothe direction of welding.

temporary weld. A weld made to attach a piece orpieces to a weldment for temporary use in handling,shipping, or working on the weldment.

throat of a fillet weld

theoretical throat. The distance from the beginningof the joint root perpendicular to the hypotenuse ofthe largest right triangle that can be inscribed withinthe cross section of a fillet weld. This dimension isbased on the assumption that the root opening is equalto zero.

actual throat. The shortest distance between the weldroot and the face of a fillet weld.

throat of a groove weld. A nonstandard term forgroove weld size.

T-joint. A joint between two members located approxi-mately at right angles to each other in the form of a T.

toe of weld. See weld toe.

*transverse discontinuity. A weld discontinuity whosemajor dimension is in a direction perpendicular to theweld axis “X.”

Uundercut. A groove melted into the base metal adjacent

to the weld toe or weld root and left unfilled by weldmetal.

UT. Ultrasonic testing.

V*vertical welding position. The position of welding in

which the axis of the weld is approximately vertical[see Figures 5.4, 5.5, 5.6(C), and 5.7(C)].

V-path (UT). The distance a shear wave sound beamtravels from the search unit test material interface tothe other face of the test material and back to the orig-inal surface.

Wweave bead. A type of weld bead made with transverse

oscillation.

weld. A localized coalescence of metals or nonmetalsproduced either by heating the materials to the weld-ing temperature, with or without the application ofpressure or by the application of pressure alone, andwith or without the use of filler metal.

weldability. The capacity of a material to be weldedunder the imposed fabrication conditions into a spe-cific, suitably designed structure and to perform satis-factorily in the intended service.

weld axis. A line through the length of a weld, per-pendicular to and at the geometric center of its crosssection.

weld bead. A weld resulting from a pass. See stringerbead and weave bead.

welder. One who performs a manual or semiautomaticwelding.

*welder certification. Certification in writing that awelder has produced welds meeting prescribed stan-dards. Certification is only effective when the welderor welding operator meets the currency requirementsof Clause 5, Parts C and D.

welder performance qualification. The demonstrationof a welder’s ability to produce welds meeting speci-fied standards.


215

weld face. The exposed surface of a weld on the sidefrom which welding was done.

welding. A joining process that produces coalescence ofmaterials by heating them to the welding temperature,with or without the application of pressure alone, andwith or without the use of filler metal. See the MasterChart of Welding Processes, AWS A3.0.

welding machine. Equipment used to perform the weld-ing operation. For example, spot welding machine,arc welding machine, and seam welding machine.

welding operator. One who operates adaptive control,automatic, mechanized, or robotic welding equipment.

*welding procedure. The detailed methods and prac-tices including all joint welding procedures involvedin the production of a weldment. See joint weldingprocedure.

welding procedure specification (WPS). A documentproviding the required variables for a specific applica-tion to assure repeatability by properly trained weld-ers and welding operators.

welding sequence. The order of making the welds in aweldment.

weldment. An assembly whose component parts arejoined by welding.

weld pass. A single progression of welding along a joint.The result of a pass is a weld bead or layer.

weld reinforcement. Weld metal in excess of the quan-tity required to fill a joint.

weld root. The points, shown in cross section, at whichthe root surface intersects the base metal surfaces.

weld size

fillet weld size. For equal leg fillet welds, the leglengths of the largest isosceles right triangle whichcan be inscribed within the fillet weld cross section.For unequal leg fillet welds, the leg lengths of thelargest right triangle that can be inscribed within thefillet weld cross section.

groove weld size. The joint penetration of a grooveweld.

weld tab. Additional material that extends beyond eitherend of the joint, on which the weld is started orterminated.

weld toe. The junction of the weld face and the basemetal.



216


217

E1. Purpose

The purpose of these requirements is to prescribe testsfor the stud manufacturer’s certification of a stud basefor welding under shop or field conditions.

E2. Responsibility for Tests

The stud manufacturer shall be responsible for the per-formance of the qualification test. These tests may beperformed by a testing agency satisfactory to the Engi-neer. The agency performing the tests shall submit a cer-tified report to the manufacturer of the studs givingprocedures and results for all tests including the informa-tion described under E10.

E3. Extent of Qualification

Qualification of a stud base shall constitute qualificationof stud bases with the same geometry, flux, and arcshield, having the same diameter and diameters that aresmaller by less than 3 mm [1/8 in]. For example, qualifi-cation of a 19 mm [3/4 in] shank diameter stud base shallnot constitute qualification for a 16 mm [5/8 in] shank di-ameter stud, but would constitute qualification for a studbase having a shank diameter of 17 mm [5/8 in]. A studbase qualified with an approved grade of ASTM A 108steel shall constitute qualification for all other approvedgrades of A 108 steel (see 7.3.1) provided that all otherprovisions described herein are complied with.

E4. Duration of Qualification

A size of stud base with arc shield, once qualified, shall beconsidered qualified until the stud manufacturer makesany change in the stud-base geometry, material, flux, orarc shield which affects the welding characteristics.

E5. Preparation of Specimens

E5.1 Test specimens shall be prepared by welding repre-sentative studs to suitable specimen plates of Grade 250[36] steel or any of the other materials described in 1.2.2.When studs are to be welded through decking, the stud-base qualification test shall include decking representa-tive of that to be used in construction. Welding shall bedone in the flat position (plate surface horizontal). Testsfor threaded studs shall be on blanks (studs withoutthreads).

E5.2 Studs shall be welded with power source, weldinggun, and automatically controlled equipment as recom-mended by the stud manufacturer. Welding voltage, cur-rent, and time (see E6) shall be measured and recordedfor each specimen. Lift and plunge shall be at the opti-mum setting as recommended by the manufacturer.

E6. Number of Test Specimens

E6.1 For studs 22 mm [7/8 in] or less in diameter, thirtytest specimens shall be welded consecutively with con-stant optimum time, but with current 10% above opti-mum. For studs over 22 mm [7/8 in] diameter, 10 testspecimens shall be welded consecutively with constantoptimum time, but current and time shall be the midpoint

Annex E (Normative)

Manufacturer’s Stud Base Qualification Requirements


ANNEX E AASHTO/AWS D1.5M/D1.5:2008

218

of the range normally recommended by the manufacturerfor production welding.

E6.2 For studs 22 mm [7/8 in] or less in diameter, 30 testspecimens shall be welded consecutively with constantoptimum time, but with current 10% below optimum. Forstuds over 22 mm [7/8 in] diameter, 10 test specimensshall be welded consecutively with constant optimumtime, but with current 5% below optimum.

E7. Tests

E7.1 Tension Tests. Ten of the specimens welded inconformance with E6.1 and ten in conformance withE6.2 shall be subjected to a tension test in a fixture simi-lar to that shown in Figure 7.2, except that studs withoutheads may be gripped on the unwelded end in the jaws ofthe tension testing machine. A stud base shall be consid-ered as qualified if all test specimens have a tensilestrength equal to or above the minimum described in7.3.1.

E7.2 Bend Test Studs 22 mm or Less in Diameter.Twenty of the specimens welded in conformance withE6.1 and twenty in conformance with E6.2 shall be bendtested by being bent alternately 30° from their originalaxis in opposite directions until failure occurs. Studsshall be bent in a bend testing device as shown in FigureE.1A, except that studs less than 12 mm [1/2 in] diameter,may be bent using a device as shown in Figure E.1B. Astud base shall be considered as qualified if, on all testspecimens, fracture occurs in the plate material or shankof the stud and not in the weld or HAZ. All test speci-

mens for studs over 22 mm [7/8 in] will be tested onlyfor tensile strength, Figure 7.2.

E8. RetestsIf failure occurs in a weld or the HAZ in any of the bendtest groups of E7.2 or at less than specified minimumtensile strength of the stud in any of the tension groups inE7.1, a new test group (described in E6.1 or E6.2, as ap-plicable) shall be prepared and tested. If such failures arerepeated, the stud base shall fail to qualify.

E9. AcceptanceFor a manufacturer’s stud base and arc shield combina-tion to be qualified, each stud of each group of 30 studsshall, by test or retest, meet the requirements described inE7. Qualification of a given diameter of stud base shallbe considered qualification for stud bases of the samenominal diameter (see E3, stud-base geometry, material,flux, and arc shield).

E10. Manufacturer’s Qualification Test Data

The test data shall include the following:(1) Drawings showing shapes and dimensions with

tolerances of stud, arc shields, and flux(2) A complete description of materials used in the studs,

including the quantity and type of flux, and a descriptionof the arc shields

(3) Certified results of required laboratory tests

AASHTO/AWS D1.5M/D1.5:2008 ANNEX E

219

Notes:1. Fixture holds specimen and stud shall be bent 30° alternately

in opposite directions.2. Load may be applied with hydraulic cylinder (shown) or fixture

adapted for use with tension test machine.

Figure E.1A—Bend Testing Device (see E7.2)

E.1B—Suggested Type of Device forQualification Testing of Small Studs

(see E7.2)



220


221

FA1. Longitudinal Mode

FA1.1 Distance Calibration

FA1.1.1 The transducer shall be set in position

H on the DC block, orM on the DSC block

FA1.1.2 The instrument shall be adjusted to produceindications at 25 mm [1 in], 50 mm [2 in], 75 mm [3 in],100 mm [4 in], etc., on the display.

NOTE: This procedure establishes a 250 mm [10 in]screen calibration and may be modified to establishother distances as allowed by 6.18.4.1.

FA1.2 Amplitude. With the transducer in positiondescribed in GA1.1, the gain shall be adjusted until themaximized indication from the first back reflection attains50% to 75% screen height.

FA2. Shear Wave Mode (Transverse)FA2.1 Sound Entry (Index) Point Check

FA2.1.1 The search unit shall be set in position J or Lon the DSC block; or I on the DC block.

FA2.1.2 The search unit shall be moved until thesignal from the radius is maximized.

FA2.1.3 The point on the search unit that is in linewith the line on the calibration block shall be indicativeof the point of sound entry.

NOTE: Use this sound entry point for all further distanceand angle checks.

FA2.2 Sound Path Angle Check

FA2.2.1 The transducer shall be set in position:

K on the DSC block for 45° through 70°N on the SC block for 70°O on the SC block for 45°P on the SC block for 60°

FA2.2.2 The transducer shall be moved back andforth over the line indicative of the transducer angle untilthe signal from the radius is maximized.

FA2.2.3 The sound entry point on the transducer shallbe compared with the angle mark on the calibrationblock (tolerance ±2°).

FA2.3 Distance Calibration

FA2.3.1 The transducer shall be set in position L onthe DSC block. The instrument shall be adjusted to attainindications at 75 mm [3 in] and 180 mm [7 in] on thedisplay.

FA2.3.2 The transducer shall be set in position J onthe DSC block (any angle). The instrument shall beadjusted to attain indications at 25 mm [1 in], 125 mm[5 in], and 230 mm [9 in] on the display.

Annex F (Normative)


Part AQualification and Calibration of the UT Unit withOther Approved Reference Blocks (see Figure F.1)

ANNEX F AASHTO/AWS D1.5M/D1.5:2008

222

FA2.3.3 The transducer shall be set in position I onthe DC block (any angle). The instrument shall be ad-justed to attain indication at 25 mm [1 in], 50 mm [2 in],75 mm [3 in], 100 mm [4 in], etc., on the display.

NOTE: This procedure establishes a 250 mm [10 in]screen calibration and may be modified to establishother distances as allowed by 6.18.5.1.

FA2.4 Amplitude or Sensitivity Calibration

FA2.4.1 The transducer shall be set in position L onthe DSC block (any angle). The maximized signal fromthe 0.8 mm [1/32 in] slot shall be adjusted to attain a hor-izontal reference-line height indication.

FA2.4.2 The transducer shall be set on the SC blockin position:

N for 70° angleO for 45° angleP for 60° angle

The maximized signal from the 1.6 mm [1/16 in] holeshall be adjusted to attain a horizontal reference-lineheight indication.

FA2.4.3 The decibel reading obtained in EIA2.4.1 orEIA2.4.2 shall be used as the “reference level, “b” onthe Test Report Sheet (Annex F, Part B, Form F-4) inconformance with 6.16.1.

FA3. Horizontal Linearity ProcedureNOTE: Since this qualification procedure is performed witha straight beam search unit which produces longitudinalwaves with a sound velocity of almost double that of shearwaves, it shall be necessary to double the shear wavedistance ranges to be used in applying this procedure.

FA3.1 A straight beam search unit meeting the require-ments of 6.15.6 shall be coupled in position:

G on the IIW block (Figure 6.6)T or U on the DS block (Figure 6.6)

FA3.2 A minimum of 5 back reflections shall be attainedin the qualification range being certified.

FA3.3 The first and fifth back reflections shall be ad-justed to their proper locations with use of the distancecalibration and zero delay adjustments.

FA3.4 Each indication shall be adjusted to referencelevel with the gain or attenuation control for horizontallocation examination.

FA3.5 Each intermediate trace deflection location shallbe correct within ±2% of the screen width.

PART A

223

AASHTO/AWS D1.5M/D1.5:2008 ANNEX F

Part BUT Equipment Qualification Procedures

This annex contains examples for use of three forms, F-1, F-2, and F-3, recording of UT data. Each example of formsF-1, F-2, and F-3 shows how the forms may be used during the UT of welds. Form F-4 is for reporting results of UT ofwelds.

PART B


224

Figure F.1—Example of the Use of Form F-1 UT Unit Certification


225

Figure F.2—Example of Form F-2


226

Note: The first line of example of the use of form F-2 is shown in this example.

Figure F.3—Example of the Use of Form F-2


227

Figure F.4—Example of Form F-3


228

Notes:1. The 6 dB reading and 69% scale are derived from the instrument reading and become dB “b1” and %1 “c” respectively.2. %2 is 78 – constant.3. dB2 (which is corrected dB “d”) is equal to 20 times × log (78/69) + 6 or 7.1.

Notes: Procedure for using the Nomograph:1. Extend a straight line between the decibel reading from Column A applied to the C scale and the corresponding percentage from

Column B applied to the A scale.2. Use the point where the straight line from Step 1 crosses the pivot line B as a pivot line for a second straight line.3. Extend a second straight line from the average sign point on the A scale, through the pivot point developed in Step 2, and onto the dB

scale C.4. This point on the C scale is indicative of the corrected dB for use in Column C.

Figure F.5—Example of the Use of Form F-3


229

REPORT OF UT OF WELDSProject _________________________________________________________________________ Report no. _________________

Figure F.6—Form F-4—Report of UT of Welds

Weld identification____________________________________________________

Material thickness ____________________________________________________

Weld joint AWS ______________________________________________________

Welding process _____________________________________________________

Quality requirements—section no. _______________________________________

Remarks ___________________________________________________________

Line

num

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Dis

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Remarks

Indi

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Atte

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Leng

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Ang

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Distance

a b c d From X From Y123456789

1011121314151617181920212223242526

We, the undersigned, certify that the statements in this record are correct and that the welds were prepared and tested in conformancewith the requirements of Section 6, Part F of AASHTO/AWS D1.5M/D1.5, ( __________ ) Bridge Welding Code.

(year)

Test Date ___________________________________________

Inspected By ________________________________________

Manufacturer or Contractor ____________________________

Authorized By _______________________________________

a Use Leg I, II, or III. See glossary of terms (Annex D).

Notes:

Date ______________________________________________

1. In order to attain Rating “d”a. With instruments with gain control, use the formula a – b – c = d.b. With instruments with attenuation control, use the formula b – a – c = d.c. A plus or minus sign shall accompany the “d” figure unless “d” is equal to zero.

2. Distance from X is used in describing the location of a weld discontinuity in a direction perpendicular to the weld reference line. Unlessthis figure is zero, a plus or minus sign shall accompany it.

3. Distance from Y is used in describing the location of a weld discontinuity in a direction parallel to the weld reference line. This figure isattained by measuring the distance from the “Y” end of the weld to the beginning of said discontinuity.

4. Evaluation of Retested Repaired Weld Areas shall be tabulated on a new line on the report form. If the original report form is used, Rnshall prefix the indication number. If additional forms are used, the R number shall prefix the report number.



230


231

G1. IntroductionThe purpose of this guide is to provide some optional al-ternative methods for determining welding conditions(principally preheat) to avoid cold cracking. The methodsare based primarily on research on small scale tests car-ried out over many years in several laboratories world-wide. No method is available for predicting optimumconditions in all cases, but the guide does consider severalimportant factors such as hydrogen level and steel com-position not explicitly included in the requirements ofTable 4.4. The guide may therefore be of value in indicat-ing whether the requirements of Table 4.4 are overly con-servative or in some cases not sufficiently demanding.

The user is referred to the Commentary, AWS D1.1,Structural Welding Code—Steel, for more detailed pre-sentation of the background scientific and research infor-mation leading to the two methods proposed.

In using this guide as an alternative to Table 4.4, carefulconsideration shall be given to the assumptions made,the values selected, and past experience.

G2. MethodsTwo methods are used as the basis for estimating weld-ing conditions to avoid cold cracking:

(1) HAZ hardness control

(2) Hydrogen control

G3. HAZ Hardness ControlG3.1 The provisions included in this guide for use of thismethod shall be restricted to fillet welds.

G3.2 This method is based on the assumption that crack-ing will not occur if the hardness of the HAZ is keptbelow some critical value. This is achieved by control-ling the cooling rate below a critical value dependent onthe hardenability of the steel. Hardenability of steel inwelding relates to its propensity towards formation of ahard HAZ and can be characterized by the cooling ratenecessary to produce a given level of hardness. Steelswith high hardenability can, therefore, produce a hardHAZ at slower cooling rates than a steel with lower hard-enability. Equations and graphs are available in the tech-nical literature that relate the weld cooling rate to thethickness of the steel members, type of joint, weldingconditions, and variables.

G3.3 The selection of the critical hardness will dependon a number of factors such as steel type, hydrogen level,restraint and service conditions. Laboratory tests with fil-let welds show that HAZ cracking does not occur if theHAZ Vickers Hardness No. (HV) is less than 350 HVeven with high-hydrogen electrodes. With low-hydrogenelectrodes, hardnesses of 400 HV may be tolerated with-out cracking. Such hardnesses, however, may not be tol-erable in service where there is an increased risk of stresscorrosion cracking, brittle fracture initiation, or otherrisks for the safety or serviceability of the structure.

The critical cooling rate for a given hardness may be ap-proximately related to the carbon equivalent of the steel(see Figure G.2). Since the relationship is only approxi-mate, the curve shown in Figure G.2 may be conservativefor plain carbon and plain-carbon-manganese steels andthus allow the use of the high hardness curve with lessrisk. Some low-alloy steels, particularly those containingcolumbium (niobium), may be more hardenable than Fig-

Annex G (Normative)

Guidelines on Alternative Methods for Determining Preheat


ANNEX G AASHTO/AWS D1.5M/D1.5:2008

232

ure G.2 indicates, and the use of the lower hardness curveis recommended.

G3.4 Although the method may be used to determine apreheat level, its main value is in determining the mini-mum heat input (and hence minimum weld size) thatprevents excessive hardening. It is particularly useful fordetermining the minimum size of single-pass fillet weldsthat can be deposited without preheat.

G3.5 The hardness approach does not consider the pos-sibility of weld metal cracking, but from experience ithas been found that the heat input determined by thismethod is usually adequate to prevent weld metal crack-ing in most cases in fillet welds if the electrode is not ahigh-strength filler metal; generally, it should be a low-hydrogen type (e.g., low-hydrogen [SMAW] electrode,GMAW, FCAW, SAW).

G3.6 Because the method depends solely on controllingthe HAZ hardness, the hydrogen level and restraint arenot explicitly considered.

G3.7 This method shall not be applicable to quenchedand tempered steels (see G5.2.3 for limitations).

G4. Hydrogen ControlG4.1 The hydrogen control method is based on the as-sumption that cracking will not occur if the averagequantity of hydrogen remaining in the joint after it hascooled down to about 50°C [120°F] does not exceed acritical value dependent on the composition of the steeland the restraint. The preheat necessary to allow exces-sive hydrogen to diffuse out of the joint can be estimatedusing this method.

G4.2 This method is based mainly on results of re-strained PJP groove weld tests; the weld metal used inthe tests matched the parent metal.

There has not been extensive testing of this method onfillet welds; however, by allowing for restraint, themethod has been suitably adapted for those welds.

G4.3 A determination of the restraint level and the origi-nal hydrogen level in the weld pool shall be required forthe hydrogen method. In this guide, restraint shall beclassified as high, medium, and low and the categoryshall be established from experience.

G4.4 The hydrogen control method is based on a singlelow heat input weld bead representing a root pass and as-sumes that the HAZ hardens. The method shall be, there-fore, particularly useful for high-strength, low-alloysteels having quite high hardenability where hardnesscontrol is not always feasible. Consequently, because it

assumes that the HAZ fully hardens, the predicted pre-heat may be too conservative for carbon steels.

G5. Selection of MethodThe following procedure, for selection of the moreappropriate method of G3 or G4, is recommended as aguide.

G5.1 Both the carbon content and carbon equivalent ofthe steel should be determined:

CE = C +

to locate the zone classification of the steel in Figure G.1(see G6.1.1 for different ways to obtain the chemicalanalysis).

G5.2 The performance characteristics of each zone andthe recommended action are as follows:

G5.2.1 Zone I. Cracking is unlikely but may occurwith high hydrogen or high restraint. The hydrogen con-trol method should be used to determine preheat forsteels in this zone.

G5.2.2 Zone II. The hardness control method shouldbe used and HV350 or HV400 hardness number shouldbe selected to determine the minimum energy input forsingle-pass fillet welds without preheat. If that energyinput is not practical, the hydrogen method should beused to determine preheat.

(1) For groove welds, the hydrogen control methodshould be used to determine preheat.

(2) For steels with high carbon, a minimum energy tocontrol hardness and a minimum preheat to control hy-drogen both may be required, for fillet welds and forgroove welds.

G5.2.3 Zone III. The hydrogen control methodshould be used. Where heat input is restricted to preservethe HAZ properties (e.g., some quenched and temperedsteels), the hydrogen control method should be used todetermine preheat.

G6. Detailed Computation GuideG6.1 Hardness Method

G6.1.1 Calculate the carbon equivalent as follows:

CE = C +

(Mn + Si)6

----------------------- (Cr + Mo + V)5

----------------------------------- (Ni + Cu)15

-----------------------+ +

(Mn + Si)6

----------------------- (Cr + Mo + V)5

----------------------------------- (Ni + Cu)15

-----------------------+ +

AASHTO/AWS D1.5M/D1.5:2008 ANNEX G

233

The chemical analysis may be obtained from the following:

(1) Mill test certificates

(2) Typical production chemical analysis (from themill)

(3) Specification chemical analysis (using maximumvalues)

(4) User tests (chemical analysis)

G6.1.2 The critical cooling rate shall be determinedfor a selected maximum HAZ hardness of either 400 HVor 350 HV, from Figure G.2.

G6.1.3 Using applicable thicknesses for “flange” and“web” plates, the appropriate diagram from Figure G.3shall be selected and the minimum input energy shall bedetermined for single-pass fillet welds. Keep in mindthat this energy input applies to SAW.

G6.1.4 For other processes, the minimum energy inputfor single-pass fillet welds can be estimated by multiply-ing the energy estimated in G6.1.3 by the factors below:

Welding Process Multiplication Factor

SAW 1SMAW 1.50GMAW, FCAW 1.25

G6.1.5 Figure G.4 may be used to determine filletsizes as a function of energy input.

G6.2 Hydrogen Control Method

G6.2.1 The value of the composition parameter, Pcm,shall be calculated as follows:

Pcm = C +

The chemical analysis shall be determined as in G6.1.1.

G6.2.2 The hydrogen level shall be determined and de-fined as follows:

G6.2.2.1 H4 Extra-Low Hydrogen. Consumablesthus labeled should have the following:

(1) A diffusible hydrogen content of less than4 mL/100 g deposited metal when measured using thelatest edition of AWS A4.3, Standard Procedures forDetermination of Diffusible Hydrogen Content of Mar-tensitic, Bainitic, and Ferritic Steel Weld Metal Pro-duced by Arc Welding, or

(2) A moisture content of electrode covering of 0.2%maximum in conformance with AWS A5.1/A5.1M orA5.5/A5.5M.

This may be established by testing each type, brand,or wire/flux combination used after removal from the

Si30------ Mn

20-------- Cu

20------- Ni

60------ Cr

20------ Mo

15-------- V

10------ 5B+ + + + + + +

package or container and exposure for the intended dura-tion, with due consideration of actual storage conditionsprior to immediate use. The following may be assumed tomeet this requirement:

(a) Low-hydrogen electrodes taken from hermeti-cally sealed containers, dried at 370°C–425°C [700°F–800°F] for one hour and used within two hours after removal

(b) GMAW with clean solid wires

G6.2.2.2 H8 Low-Hydrogen. These consumablesshall conform to the following requirements:

(1) A diffusible hydrogen content of less than 8 mL/100 g deposited metal when measured using AWS A4.3 or

(2) A moisture content of electrode covering of 0.4%maximum in conformance with AWS A5.1/A5.1M.

This may be established by a test on each type, brand ofconsumable, or wire/flux combination used. The follow-ing may be assumed to meet this requirement:

(a) Low-hydrogen electrodes taken from hermeti-cally sealed containers conditioned in conformance with4.5.2 of the code and used within four hours after removal

(b) SAW with dry flux. Note that these consum-ables are expected to give a diffusible hydrogen contentof “less than 16 mL/100 g,” which may not meet this8 mL/100 g definition.

G6.2.2.3 H16 Hydrogen Limit. These other consum-ables do not meet the requirements of H4 or H8.

G6.2.3 The susceptibility index grouping from Table G.1should be determined.

G6.2.3.1 Required minimum preheat levels and inter-pass temperatures are given in Table G.2 for three levelsof restraint. The restraint level to be used shall be deter-mined in conformance with G6.2.3.2.

G6.2.3.2 Restraint. The degree of restraint of weldtypes should be determined on the basis of experience,engineering judgment, research, or calculation. Threelevels of restraint have been provided:

(1) Low Restraint. This level describes common filletand groove welded joints in which a reasonable freedomof movement of members exists.

(2) Medium Restraint. This level describes fillet andgroove welded joints in which, because of membersbeing already attached to structural work, a reduced free-dom of movement exists.

(3) High Restraint. This level describes welds inwhich there is almost no freedom of movement formembers joined (such as repair welds, especially in thickmaterial).


234

Table G.1Susceptibility Index Grouping as Function of Hydrogen Level “H”

and Composition Parameter Pcm (see G6.2.3)

Hydrogen Level, H

Susceptibility Indexb Groupingc

Carbon Equivalent =

<0.18 <0.23 <0.28 <0.33 <0.38

H4 A B C D E

H8 B C D E F

H16 C D E F G

a

b Susceptibility index—12 Pcm + log10 H.c Susceptibility Index Groupings, A through G, encompass the combined effect of the composition parameter,

Pcm, and hydrogen level, H, in conformance with the formula shown in Note b.

The exact numerical quantities shall be obtained from the Note b formula using the described values of Pcm andthe following values of H, given in mL/100 g of weld metal (see G6.2.2, a, b, c):

H4 < 4; H8 < 8; H16 < 16.

For greater convenience, Susceptibility Index Groupings have been expressed in the table by means of letters, Athrough G, to cover the following narrow ranges:

A = 3.0; B = 3.1–3.5; C = 3.6–4.0; D = 4.1–4.5; E = 4.6–5.0; F = 5.1–5.5; G = 5.6–7.0.

These groupings are used in Table G.2 in conjunction with restraint and thickness to determine the minimumpreheat and interpass temperature.

Table G.2Minimum Preheat and Interpass Temperatures for Three Levels of Restraint (see G6.2.3.1)

Restraint Level

Thicknessa

mm [in]

Minimum Preheat and Interpass Temperature, °C [°F]

Susceptibility Index Grouping

A B C D E F G

Low

<10 [3/8] <20 [65]0 <20 [65] <20 [65].0 <20 [65]0 60 [140] 135 [280] 150 [300]

10–20 [3/8–3/4] <20 [65]0 <20 [65] <20 [65]0 60 [140] 100 [210] 135 [280] 150 [300]

1-20–40 [3/4–1-1/2] <20 [65]0 <20 [65] <20 [65]0 080 [175] 110 [230] 135 [280] 150 [300]

40–75 [1-1/2–3] <20 [65]0 <20 [65] <40 [100] 95 [200] 120 [250] 135 [280] 150 [300]

>75 [3]/0 <20 [65]0 <20 [65] <40 [100] 95 [200] 120 [250] 135 [280] 150 [300]

Medium

<10 [3/8] <20 [65]0 <20 [65] <20 [65].0 <20 [65]0 70 [160] 135 [280] 160 [320]

10–20 [3/8–3/4] <20 [65]0 <20 [65] <20 [65]0 80 [175] 115 [240] 145 [290] 160 [320]

1-20–40 [3/4–1-1/2] <20 [65]0 <20 [65] 75 [165] 110 [230] 135 [280] 150 [300] 160 [320]

40–75 [1-1/2–3] <20 [65]0 80 [175] 110 [230] 130 [265] 150 [300] 150 [300] 160 [320]

>75 [3]/0 95 [200] 120 [250] 135 [280] 150 [300] 160 [320] 160 [320] 160 [320]

High

<10 [3/8] <20 [65]0 <20 [65] <20 [65].0 40 [100] 110 [230] 150 [300] 160 [320]

10–20 [3/8–3/4] <20 [65]0 <20 [65] 65 [150] 105 [220] 135 [280] 160 [320] 160 [320]

1-20–40 [3/4–1-1/2] <20 [65]0 .85 [185] 115 [240] 135 [280] 150 [300] 160 [320] 160 [320]

40–75 [1-1/2–3] .115 [240] 130 [265] 150 [300] 150 [300] 160 [320] 160 [320] 160 [320]

>75 [3]/0 .115 [265] 130 [265] 150 [300] 150 [300] 160 [320] 160 [320] 160 [320]a Thickness is that of the thicker part welded

Pcma

Pcm C + = Si30------ Mn

20-------- Cu

20------- Ni

60------ Cr

20------ Mo

15-------- V

10------ 5B+ + + + + + +


235

Notes:1. CE = C + (Mn + Si)/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15.2. See G5.2.1, G5.2.2, or G5.2.3 for applicable zone characteristics.

Figure G.1—Zone Classification of Steels (see G5.1)


236

Figure G.2—Critical Cooling Rate for 350 HV and 400 HV (see G6.1.2)


237

Note: Energy input determined from chart shall not imply suitability for practical applications. For certain combinationof thicknesses melting may occur through the thickness.

(A) SINGLE-PASS SAW FILLET WELDS WITH WEB AND FLANGE OF SAME THICKNESS

(B) SINGLE-PASS SAW FILLET WELDS WITH 6 mm [1/4 in] FLANGES AND VARYING WEB THICKNESSES

Figure G.3—Charts to Determine Cooling Ratesfor Single-Pass Submerged Arc Fillet Welds (see G6.1.3)


238


(C) SINGLE-PASS SAW FILLET WELDS WITH 12 mm [1/2 in] FLANGES AND VARYING WEB THICKNESSES


(D) SINGLE-PASS SAW FILLET WELDS WITH 25 mm [1 in] FLANGES AND VARYING WEB THICKNESSES

Figure G.3 (Continued)—Charts to Determine Cooling Ratesfor Single-Pass Submerged Arc Fillet Welds (see G6.1.3)


239

(E) SINGLE-PASS SAW FILLET WELDS WITH 50 mm [2 in] FLANGES AND VARYING WEB THICKNESSES


(F) SINGLE-PASS SAW FILLET WELDS WITH 100 mm [4 in] FLANGES AND VARYING WEB THICKNESSES

Figure G.3 (Continued)—Charts to Determine Cooling Ratesfor Single-Pass Submerged Arc Fillet Welds (see G6.1.3)


240

(A) SHIELDED METAL ARC WELDING (SMAW)

(B) SUBMERGED ARC WELDING (SAW)

Figure G.4—Relation Between Fillet Weld Size and Energy Input (see G6.1.5)


241

H1. PurposeAnnex H provides the requirements for welding M270M[M270] (A 709M [A 709]) Grade HPS 485W [HPS 70W]with reduced preheat using heat input and diffusible hydro-gen controls for welding consumables. All provisions ofthe code shall apply except as modified herein. Theserequirements apply to joining HPS 485W [HPS 70W] toitself or to hybrid joints joining HPS 485W [HPS 70W] tolower strength materials, based on the AASHTO approveddocument Guide Specification for Highway Bridge Fabri-cation with HPS70W, 2nd Edition.

H2. Filler Metal RequirementsThe filler metals for matching and undermatchingstrength weldments shall comply with all requirementsof the Table H.2, with the additional requirement that thediffusible hydrogen content shall be 4 mL/100 g or lesswhen using the preheat and interpass temperatures de-scribed in Annex Table G.1.

Consumable handling, regardless of welding process orpreheat and interpass temperatures, shall be controlled inaccordance with 12.6.5, 12.6.6, and 12.6.7 of this code,except that:

(1) Consumables may be handled according to theconsumable manufacturer’s recommendations for stor-age and handling procedures if they differ from those ofAWS D1.5 subclauses 12.6.5, 12.6.6, and 12.6.7, and themanufacturer certifies that the diffusible hydrogen leveldoes not exceed 4 mL/100 g using their recommendations.

(2) Consumables shall be handled according to theconsumable manufacturer’s recommendations for stor-age and handling procedures when they are more restric-tive than those of AWS D1.5 subclauses 12.6.5, 12.6.6,and 12.6.7.

Fluxes for the SAW process received in undamaged, her-metically sealed containers may be used directly fromthe container without baking. Flux received in moistureresistant packaging shall be baked in accordance with12.6.6.3 prior to use, consistent with the manufacturersrecommendations for the maximum baking temperature.

H3. Additional NDT Testing Requirement

In addition to the testing requirements of 5.15, 5.16, and5.17, the Procedure Qualification Record (PQR) testplate shall be ultrasonically tested (UT) in accordancewith Clause 6, Inspection, Part C of this code. Evaluationmust be in accordance with Table 6.3, UT Acceptance-Rejection Criteria—Tensile Stress, of this code. Indica-tions found at the interface of the backing and test platesshall be disregarded, regardless of the defect rating.

H4. WPS

Welding procedure qualification of fillet welds shall bequalified using the alternative reduced preheat and inter-pass of Annex H.

Annex H (Normative)

Welding Requirements for Conventional, Nonfracture CriticalM270M [M270] (A 709M [A 709]) HPS 485W [HPS 70W]

Components with Reduced Preheat and Interpass Temperature


ANNEX H AASHTO/AWS D1.5M/D1.5:2008

242

Table H.1Minimum Preheat and Interpass Temperature

for M270M [M270] (A 709M [A 709]) HPS 485W [HPS 70W], °C [°F]a

Welding Processc, d

DiffusibleHydrogen

Max.

Thickness of Thickest Part at Point of Welding, mm [in]b

To 20 [3/4] incl.Over 20 to 40

[3/4 to 1-1/2] incl.Over 40 to 65

[1-1/2 to 2-1/2] incl. Over 65 [2-1/2]

SAW, SMAWFCAW, GMAW

4 mL/100 g4 mL/100 g

10 [50]10 [50]

20 [70]20 [70]

20 [70]065 [150]

50 [125]110 [225]

a If satisfactory results are not achieved with minimum preheat and interpass temperatures during development of the Welding Procedure Specification(WPS), and an increased preheat temperature is used to provide a satisfactory Procedure Qualification Record (PQR), the higher preheat temperatureshall be the required minimum during bridge fabrication.

b The minimum preheat or interpass temperature required for a joint composed of different base metals and/or thicknesses shall be based on the higherof the minimum preheat required by AWS D1.5, Table 4.4 for non-HPS 485W [HPS 70W] base metal or Table H.1 above for HPS 485W [HPS 70W]base metal.

c Heat input for SAW shall be limited to 1.6 kJ/mm [40 kJ/in] minimum to a 3.5 kJ/mm [90 kJ/in] maximum, unless otherwise qualified.d Short-circuiting and Pulsed GMAW transfer modes shall not be allowed.

Table H.2Filler Metals for Use with the Reduced Preheat of

Table H.1, Diffusible Hydrogen Levels 4 mL/100 g Maximuma

Welding Process AWS Specification/Classification

Matching Strength for Joining HPS 485W [HPS 70W] Steel

SAW A5.23/F9A4-EXXX-XXX

FCAW A5.29/E80T1-K2A5.29/E90T5-K2

GMAW—Metal Core A5.28/E90C-G

SMAW A5.5/E9018MH4A5.5/E9018MH4R

Undermatching Strength for Joining HPS 485W [HPS 70W] Steel

SAW A5.17 or A5.23/F7A0-EXXXA5.17 or A5.23/F8A0-EXXX

FCAW A5.20/E71T-12J

SMAW A5.1/E7018H4A5.1/E7018H4RA5.5/E8018-C3H4A5.5/E8018-C3H4R

Matching Strength for Joining HPS 485W [HPS 70W] to HPS 345W [HPS 50W] or 345W [50W] Steel

SAW A5.17 or A5.23/F7A0-EXXXA5.17 or A5.23/F8A0-EXXX

SMAW A5.1/E7018H4A5.1/E7018H4RA5.5/E8018-C3H4A5.5/E8018-C3H4R

a Specific manufacturer’s consumables are listed in the AASHTO approved Guide Specification for Highway BridgeFabrication with HPS70W.


243

Notes:1. A—minimum clearance allowed between edges of porosity or fusion-type discontinuities 2 mm [1/16 in] or larger. Larger of adjacent

discontinuities governs.2. X1—largest allowable porosity or fusion-type discontinuity for 20 mm [3/4 in] joint thickness (see Figure 6.8).3. X2, X3, X4—porosity or fusion-type discontinuity 2 mm [1/16 in] or larger, but less than maximum allowable for 20 mm [3/4 in] joint

thickness.4. X5, X6—porosity or fusion-type discontinuity less than 2 mm [1/16 in].5. Discontinuity size indicated is assumed to be its greatest dimension.6. Porosity or fusion-type discontinuity X4 is not acceptable because it is within the minimum clearance allowed between edges of such

discontinuities (see 6.26.2.1 and Figure 6.8). Remainder of weld is acceptable.

Annex I (Informative)

Weld Quality Requirements for Tension Joints

This annex is not part of AASHTO/AWS D1.5M/D1.5:2008, Bridge Welding Code,but is included for informational purposes only.



244


245

J1. GeneralThis annex describes discontinuities which may or maynot be classified as unacceptable under the provisions ofthis code. Except for cracks, discontinuities are unac-ceptable only if they exceed the specification require-ments for type, size, distribution or location. All cracksare unacceptable discontinuities under the provisions ofthis code. Discontinuities may be found in the basemetal, weld metal, or heat-affected zones (HAZs) in butt,T-, corner and lap-joint configurations. The following ar-ticles present a fairly comprehensive list of discontinui-ties which may be encountered in fabrication.

J2. List of DiscontinuitiesThe most common types of discontinuities found in butt,T-, corner, and lap joints are described in Table J.1 andshown in Figures J.1 through J.6.

Weld and base-metal discontinuities of specific types aremore common when certain welding processes and jointdetails are used. High restraint and limited access to por-tions of a weld joint preparation may lead to a higher thannormal incidence of weld and base metal discontinuities.

Each general type of discontinuity is discussed in detailin this annex. The New York State Steel ConstructionManual, the AWS Structural Welding Code—Steel, andthis Bridge Welding Code use the term fusion-type dis-continuity as an all-encompassing term to describe slaginclusions, incomplete fusion, inadequate joint penetra-

tion, and similar generally elongated discontinuities inweld fusion.

Since this code requires all CJP welds without backing tobe backgouged to sound metal before welding from thesecond side, inadequate joint penetration is technicallyimpossible if all provisions of the code are met. Manycodes consider fusion discontinuities less critical thancracks. The Bridge Welding Code reflects our agreementwith this provision. Some codes specifically prohibit notonly cracks but also any area of incomplete fusion or in-adequate joint penetration. This code does not prohibitincomplete fusion or inadequate joint penetration, per se,even though these discontinuities are planar defects thatin a fracture analysis will perform in a manner similar tocracks. Incomplete fusion and inadequate joint penetra-tion defects are treated as fusion discontinuities, sincethey generally do not have the flaw tip acuity of a crackand because routine NDT generally cannot distinguishbetween the various types of fusion defects.

Specific joint types and WPSs may have an effect on thetype, location, and incidence of discontinuities. The con-ditions that may effect the formation of discontinuitiesare described in the following articles.

J2.1 Porosity. Porosity is created when gas is entrappedin solidifying metal. The discontinuity formed is gener-ally spherical but may be elongated. When there are gasdiscontinuities in ingots that are reduced to wroughtproducts, gas voids in the ingot will appear as lamina-tions in the finished product. This annex shall onlydiscusses porosity as a weld discontinuity. Unless poros-

Annex J (Informative)

Description of Common Weld and Base Metal Discontinuities

(Reprinted with modification fromNew York State Steel Construction Manual)


ANNEX J AASHTO/AWS D1.5M/D1.5:2008

246

ity is gross (large or extensive, or both), it is not so criti-cal a flaw as sharp, planar discontinuities that intensifystress. Porosity is a sign that the welding process is notbeing properly controlled or that the base metal is con-taminated or of variable composition. Porosity is notcaused exclusively by hydrogen, but the presence of po-rosity indicates that there is a possibility of hydrogen inthe weld and HAZ that may lead to cracking.

(1) Uniformly Scattered Porosity. Uniformly scatteredporosity is scattered pores distributed through a singleweld pass, or throughout several passes of a multiple-pass weld. Whenever uniformly scattered porosity is en-countered, the case is generally faulty welding techniqueor materials. Porosity will only be present in a weld if thetechnique used, materials, or the conditions of the weldjoint preparation lead to gas formation and entrapment. Ifthe weld cools slowly enough to allow gas to pass to thesurface before the weld solidifies, there will be no poros-ity in the weld.

(2) Cluster Porosity. Cluster porosity is a localizedgrouping of pores that usually results from improper ini-tiation or termination of the welding arc.

(3) Linear Porosity. Linear porosity is porosityaligned along a joint boundary, the root of the weld, or aninterbead boundary. Linear porosity is caused by con-tamination that leads to gas evolution at particular loca-tions within the weld.

(4) Piping Porosity. Piping porosity is a term forelongated (cylindrical) gas discontinuities. Piping poros-ity in fillet welds extends from the root of the weld to-wards the surface of the weld. When one or two porositydiscontinuities are seen in the surface of the weld, carefulexcavation will generally show that there are many sub-surface piping porosity discontinuities interspersedamong the exposed pores. Much of the piping porosityfound in welds does not extend all the way to the surface.Piping porosity in electroslag and electrogas welds canbecome very extensive in number and length. Pores aslong as 500 mm [20 in] have been measured in someESW welds. Piping porosity is very difficult to evaluateby UT.

J2.2 Inclusions

(1) Nonmetallic Slag. Slag inclusions result fromnonmetallic, solid material being entrapped in weldmetal, between weld passes, or between weld and basemetal. Slag inclusions can be found in welds made bymost arc WPSs. In general, slag inclusions result fromfaulty welding technique, failure to clean properly be-tween weld passes, and conditions that lead to limited ac-cess for welding within the joint. If allowed, molten slagwill float to the top of the weld. Sharp notches in joint

boundaries or between weld passes often cause slag to beentrapped under the molten weld metal.

(2) Metallic Tungsten. Tungsten inclusions are foundonly in welds made by the gas tungsten arc welding(GTAW) process. Since this process is not used underthe provisions of this code, the discontinuity is describedfor interest only. Tungsten inclusions may be found inaluminum welds made by the GTAW process. A non-consumable tungsten electrode is used to establish awelding arc between the electrode and the base metal. Ifthe tungsten electrode is dipped into the molten metal, orif the current is set too high, tungsten droplets may betransferred from the electrode to the molten metal. Tung-sten inclusions appear as light marks or areas in radio-graphs because the inspecting radiation has a higherabsorption rate in tungsten than it does in steel oraluminum.

J2.3 Incomplete Fusion. Incomplete fusion may resultfrom improper welding techniques, improper preparationof material for welding, or improper joint design. Defi-ciencies causing incomplete fusion include insufficientwelding heat, improper electrode manipulation, and lackof access to all boundaries of the weld joint that are to befused during welding. On rare occasions, weld metalmay fail to fuse to the base metal even though the pre-pared joint surface has been melted beyond the originalinterface. Tightly adhering oxides will interfere withcomplete fusion, even when there is access for weldingand proper welding procedures are used.

J2.4 Inadequate Joint Penetration. Inadequate jointpenetration is penetration of the welding arc that is lessthan required. Technically, this discontinuity can only bepresent when the WPS requires penetration of the weldmetal beyond the original joint boundaries and the welddeposit fails to penetrate the areas of weld joints that de-pend upon penetration for fusion. Inadequate joint pene-tration may result from insufficient welding heat,improper electrode manipulation or guidance, or im-proper joint design which requires melting of more basemetal than the arc can penetrate. Some WPSs have muchgreater penetrating ability than others.

This code requires that all CJP groove welds withoutbacking be backgouged to sound metal before weldingfrom the second side so that there is no possibility of in-adequate joint penetration at the root of the weld. Inbridge construction, weld joint designs calling for a spe-cific root penetration that would produce CJP groovewelds are not used.

J2.5 Undercut. Undercut considered to be a defect isgenerally the result of either an improper welding tech-nique, excessive welding heat, or both. It is generally lo-cated at the junction of the weld and base metal, at the

AASHTO/AWS D1.5M/D1.5:2008 ANNEX J

247

toe of fillet welds, or at the fusion line of groove welds.Undercut may also be encountered at the root of groovewelds made from one side only. The most serious under-cut is generally found in base metal surfaces that werevertical during welding. Undercut creates a mechanicalnotch at the fusion boundary of the weld. All welds havesome undercut if examined carefully. Undercut shall notbe considered an unacceptable weld discontinuity untilthe degree of undercutting exceeds the amount allowedby contract documents. Some undercut produces a sharpnotch defect. Other undercutting may be more rounded.Some undercut may only be seen in metallographic testswhere etched weld cross sections are examined undermagnification. The sharper and deeper the notch createdby undercutting, the more serious the defect.

J2.6 Underfill. Underfill is a depression on the face ofthe weld extending below the surface of the adjacentbase metal. Underfill results from failure of the welder orwelding operator to completely fill the weld joint as re-quired by the WPS.

J2.7 Overlap. Overlap is a sharp surface connected dis-continuity that forms a severe mechanical notch becausethe weld metal protrudes or flows beyond the toe or faceof the weld without fusion. It can occur as a result of fail-ure to control the welding process, improper selection ofwelding materials, or improper preparation of the basemetal prior to welding. Tightly adhering oxides on thebase metal may interfere with fusion, and overlap mayresult.

J2.8 Laminations. Laminations are planar discontinui-ties elongated in the rolling direction. These are mostcommonly found near the mid thickness of wroughtproducts. Laminations may be completely internal anddetectable only by NDT, or they may extend to an edgeor end where they are visible at the surface. Laminationsmay be discovered when cutting or machining exposesinternal metal structure.

Laminations are formed when gas voids (porosity), non-metallics, or ingot shrinkage cavities are rolled flat. Lam-inations generally run parallel to the surface of rolledproducts and are most commonly found in shapes andplates. Some laminations are partially roll-forge weldedalong their interface by the high temperature and pres-sure of the rolling or forging operation. The soundness ofthe roll-forged weld depends upon the presence or ab-sence of oxides or nonmetallics on the surfaces of theoriginal voids. Laminations that are partially or com-pletely roll-forge welded may conduct sound across theinterface and therefore may not be accurately evaluatedby UT. Metals containing laminations generally cannotbe relied upon to transmit tensile stresses in the through-

thickness direction. Laminations may be a source of gasvoids and cracks in adjacent butt welds.

J2.9 Delamination. Delamination is the separation of apartially or completely roll-forge welded laminationunder stress. The stress may be residual stress fromwelding or applied stress. Delaminations may be foundvisually at the edges or ends of pieces or may be discov-ered by UT.

J2.10 Seams and Laps. Seams and laps are longitudinalbase-metal discontinuities that may be found in rolledproducts. When seams and laps are located parallel to theprincipal stress, they are generally not considered un-acceptable discontinuities. When seams or laps are per-pendicular to the applied or residual stresses, these willoften propagate as cracks. Seams and laps are surface-connected discontinuities that result from cracks in thesurface of the ingot or mechanical deformations causedby the manufacturing process. These discontinuities aremodified during rolling so that the bottom of a seam isgenerally not so sharp as the original ingot- or slab-crack. These may be masked by mill scale or by the sur-face texture of the finished product. Welding over seamsand laps can lead to cracking.

J2.11 Lamellar Tears. Lamellar tears are somewhat ter-race-like separations in the base metal adjacent to theHAZ, typically caused by thermally induced shrinkagestresses resulting from welding. Lamellar tearing is aform of fracture resulting from high stress in the short-transverse (through-thickness) direction, which may ex-tend over long distances. The tears are roughly parallel tothe surface of the rolled product and generally initiate inregions of the base metal having a high incidence of co-planar, stringer-like nonmetallic inclusions. These inclu-sions are usually manganese sulfides in areas of the basemetal subject to high residual stress. The fracture usuallypropagates from one lamellar plane to another by shearalong lines that are roughly normal to the rolled surface.Lamellar tearing is exacerbated by hydrogen and may bethought of as a form of hydrogen cracking. Low-sulfursteels and steels with controlled sulfur morphology haveimproved resistance to lamellar tearing.

J2.12 Cracks. Weld and base-metal cracks exclusive offatigue cracks occur in weld and base metal when local-ized stresses exceed the ultimate strength of the material.Cracking is generally associated with stress amplifica-tion near discontinuities in welds and base metal, or nearmechanical notches associated with weldment design.High residual stresses are generally present, and hydro-gen embrittlement is often a contributor to crack for-mation. Welding-related cracks are generally brittle innature, exhibiting little plastic deformation at the crackboundaries.


248

Cracks can be classified as either hot or cold cracks. Hotcracks develop at elevated temperatures. These com-monly form upon solidification of the metal at tempera-tures near the melting point. Cold cracks, sometimescalled delayed cracks or hydrogen cracks, can formhours and even months after the completion of weldingand are commonly associated with hydrogen embrittle-ment. Cold cracks propagate both between and throughthe grains. Cracks may be termed longitudinal or trans-verse, depending upon their orientation. All cracks resultfrom tensile stress, which may be a combination of resid-ual, secondary, and applied stress. Crack initiation andpropagation is greatly influenced by the presence of dis-continuities that concentrate stress.

J2.12.1 Longitudinal Cracks. When a crack is paral-lel to the axis of the weld, it is called a longitudinal crackregardless of whether it is along the centerline of theweld metal, or in the HAZ of the base metal. Longitudi-nal cracks in submerged arc welds, made by automaticwelding procedures, are often associated with high weld-ing speeds and sometimes are aggravated by segregationof weld metal constituents or by extensive porosity thatdoes not show on the surface of the weld. Longitudinalcracks in small welds between heavy sections are oftenthe result of high cooling rates and high restraint.

J2.12.2 Transverse Cracks. Transverse cracks areperpendicular to the axis of the weld. They may be inweld metal, base metal, or both. Transverse cracks maybe limited in size and contained completely within theweld, or may propagate from the weld metal into the ad-jacent HAZ and into the unaffected base metal. Trans-verse cracks initiating in weld metal are commonly theresult of longitudinal shrinkage stresses acting upon ex-cessively hard (brittle) weld metal. Transverse cracksinitiating in the HAZ are generally hydrogen cracks.

J2.12.3 Crater Cracks. Crater cracks are cracks thatform in the crater or depression that is formed by im-proper termination of the welding arc. Crater cracks areshallow, hot cracks that usually form a multipointed star-like cluster, although they may have other shapes.

J2.12.4 Throat Cracks. Throat cracks are longitudi-nal cracks that are generally located in the center of theweld bead. These are generally, but not always, hotcracks.

J2.12.5 Toe Cracks. Toe cracks are generally coldcracks. These initiate or propagate from the toe of theweld where restraint stresses are highest. Toe cracks ini-tiate approximately normal to the base-metal surface butmore accurately normal to the tensile stress acting at thatlocation and propagate to various depths in the basemetal depending upon the residual stress and toughnessof the base metal.

J2.12.6 Root Cracks. Root cracks are generally lon-gitudinal cracks in the root of the weld. Root cracks aregenerally hot cracks.

J2.12.7 Underbead and HAZ Cracks. Underbeadand HAZ cracks are almost always cold cracks that formin the HAZ. These are generally short cracks but mayjoin to form much larger continuous cracks. Underbeadand HAZ cracks generally align themselves with weldboundaries that concentrate residual stresses. Underbeadcracking and all other hydrogen cracks can become a se-rious problem when three elements are present: a suscep-tible microstructure, high residual stress, and hydrogen.

J2.12.8 Fissures. The term fissure is used to describesmall to moderate size separations along prior austenitegrain boundaries. This discontinuity is commonly foundin electroslag and electrogas welds. Fissures occur inother welds, but they are easier to detect in ESW weldsbecause of the much larger prior austenite grain size.When ESW welds are subject to high restraint, and hy-drogen is present, fissuring may become a major prob-lem. Fissuring in ESW and EGW welds is generallyrestricted to the center portion of the weld that is subjectto high tensile residual stress resulting from solidifica-tion. Fissures can be either hot or cold cracks, althoughcold cracking is more common. The term microfissure isused for cracks that are so small that magnification mustbe used to detect the separation. The term macrofissureis used when the separation is large enough to be seenwith the unaided eye.

J2.13 Fatigue Cracks. Fatigue cracks are different fromthe cracks described in B2.12 of this Annex in that theyrepresent cumulative damage from repeated applicationsof load. Fatigue cracks may extend preexisting cracks ofany origin or may develop as new cracks from stressconcentrations resulting from weld flaws or structuraldetails.

The process of fatigue cracking left unchecked can prop-agate subcritical cracks to critical size at which point,brittle fracture will occur. The difference between weldquality standards for buildings and those specified forbridges is based upon the knowledge that bridge mem-bers subject to significant stress range and cycles of loadare subject to fatigue crack initiation and growth; stati-cally loaded structures are not.

Fatigue life of a structural member is the sum of initia-tion life plus propagation life until critical crack size isreached and failure occurs. Initiation life is generallymuch greater than propagation life, so it is essential thatstructures not be placed in service with known preexist-ing cracks (see Fracture and Fatigue Control in Struc-tures—Applications of Fracture Mechanics, 2nd Edition,by Barsom and Rolfe, Prentice-Hall Inc.).


249

Table J.1Common Types of Discontinuities (see J2)

Type of Discontinuity Location Remarks

1) Porositya) Uniformly scatteredb) Clusterc) Lineard) Piping

W Weld only, as discussed herein. (Porosity is also commonly found in castings.)

2) Inclusionsa) Nonmetallic slagb) Metallic tungsten

W

3) Incomplete fusion (also called lack of fusion)

W Found at joint boundaries or between passes.

4) Inadequate joint penetration (also called lack of joint penetration)

W Found at root of weld preparation.

5) Undercut BM Found at junction of weld and base metal at surface.

6) Underfill W Found at outer surface of joint penetration.

7) Overlap W Found at junction of weld and base metal at surface.

8) Laminations BM Found in base metal, generally near mid-thickness of section.

9) Delamination BM Found in base metal, generally near mid-thickness of section.

10) Seams and laps BM Found at base metal surface. Almost always longitudinal.

11) Lamellar tears BM Found in base metal near weld HAZ.

12) Cracksa) Longitudinalb) Transversec) Craterd) Throate) Toef) Rootg) Underbead and HAZh) Fissures

W, HAZ, BMW, HAZ, BM

WWHZW

HAZW

Found in weld or base metal adjacent to weld fusion boundary.Found in weld (may propagate from weld in HAZ and base metal).Found in weld at point where arc is terminated.Found at weld axis.Found at junction between face of weld and base metal.Found in weld metal at root.Found in base metal in HAZ (may propagate into unaffected base metal).Found in weld metal.

W — WeldBM — Base MetalHAZ — Heat-Affected Zone


250

Figure J.1—Weld in Butt Joint (see J2)


251

Figure J.2—Weld in Corner Joint (see J2)


252

Figure J.3—Weld in T-Joint (see J2)


253

Figure J.4—Weld in Lap Joint (see J2)

Figure J.5—Single-Pass Fillet Weld in T-Joint (see J2)


254

Figure J.6—Single-V-Groove Weld in Butt Joint (see J2)


255

Short circuiting transfer is a type of metal transfer inGMAW is which melted material from a consumableelectrode is deposited during repeated short circuits.

Short circuiting arc welding uses the lowest range ofwelding currents and electrodes diameters associatedwith GMAW. Typical current ranges for steel electrodesare shown in Table K.1. This type of transfer produces asmall, fast freezing weld pool that is generally suited forthe joining of thin sections, for out-of-position welding,and for the filling of large root openings. When weldheat input is extremely low, plate distortion is small.Metal is transferred from the electrode to the work onlyduring a period when the electrode is in contact with theweld pool. There is no metal transfer across the arc gap.

The electrode contacts the molten weld pool at a steadyrate in a range of 20 to over 200 times each second. The

sequence of events in the transfer of metal and the corre-sponding current and voltage is shown in Figure K.1. Asthe wire touches the weld metal, the current increases. Itwould continue to increase if an arc did not form, asshown at E in Figure K.1. The rate of current increaseshall be high enough to maintain a molten electrode tipuntil filler metal is transferred. Yet, it should not occur sofast that it causes spatter by disintegration of the transfer-ring drop of filler metal. The rate of current increase iscontrolled by adjustment of the inductance in the powersource. The value of inductance required depends onboth the electrical resistance of the welding circuit andthe temperature range of electrode melting. The open cir-cuit voltage of the power source shall be low enough sothat an arc cannot continue under the existing weldingconditions. A portion of the energy for arc maintenanceis provided by the inductive storage of energy during theperiod of short circuiting.

Annex K (Informative)

Short Circuiting Transfer


ANNEX K AASHTO/AWS D1.5M/D1.5:2008

256

Table K.1Typical Current Ranges for Short Circuiting Transfer

Gas Metal Arc Welding of Steel (GMAW-S)

Welding Current, Amperes (Electrode Positive)

ElectrodeDiameter Flat and Horizontal Positions Vertical and Overhead Positions

in mm min. max. min. max.

0.0300.0350.045

0.80.91.2

5075

100

150175225

5075

100

125150175

AASHTO/AWS D1.5M/D1.5:2008 ANNEX K

257

Figure K.1—Oscillograms and Sketches of Short Circuiting Arc Metal Transfer



258

AASHTO/AWS D1.5/D1.5M:2008

259

Annex L (Informative)

Suggested Sample Welding Forms


This annex contains six forms that the Structural Welding Committee has approved for the recording of WPS qualifica-tion, welder qualification, welding operator qualification, and tack welder qualification data required by this code. Alsoincluded are laboratory report forms for recording the results of NDT of welds.

It is recommended that the qualification and NDT information required by this code be recorded on these forms orsimilar forms which have been prepared by the user. Variations of these forms to suit the user’s needs are allowable.These forms are available from AWS.

ANNEX L AASHTO/AWS D1.5/D1.5M:2008

260

(Manufacturer’s name________________________________________________

and address)________________________________________________

CERTIFICATION OF CONFORMANCE

Supplied to ______________________________________________________________ Date _________________

Purchase Order No. ________________________ Quantity _____________________ Project No. ____________

Reported to ______________________________________________________________________________________

Process: SMAW SAW FCAWGMAW ESW EGW

AWS A5._____and Classification Trade Name_______________________ _______________________

Material: Electrode Designation _______________________ _______________________

Wire Designation _______________________ _______________________

Flux Designation _______________________ _______________________

Gas/Gas Mixture _______________________ _______________________

This is to certify that the above noted material, as supplied under the above Purchase Order Number, is in conformancewith the requirements of AWS A5._____–_____ on _______________, ______.

(day, month) (year)

The results of the required manufacturer’s annual tests are shown on the attached Certified Material Test Report. Testresults for this Certification shall include:

(a) Mechanical Tests: Tensile and Yield Strengths (MPa [ksi]), Elongation (in 50 mm [2 in], %), and CVN test energy(J [ft·lb] at test temperature).

(b) Chemical Analysis for: C, Mn, Si, P, S, Ni, Cr, Mo, Cu, V, Al, Ti, or Zr, as required by the applicable filler metalspecification.

(c) Fillet Weld Test.

(d) Radiographic Results.

For applicable test requirements, see the appropriate AWS filler metal specification.

Signature_________________________________ Date ________________________ Title _________________

Form L-1

Form L-1—Certificate of Conformance to Requirements for Welding Electrodes

AASHTO/AWS D1.5/D1.5M:2008 ANNEX L

261

WELDING PROCEDURE SPECIFICATION (WPS)PREQUALIFIED QUALIFIED BY TESTING

or PROCEDURE QUALIFICATION RECORDS (PQR) YesAASHTO/AWS D1.5 Qualification Type 5.12.1 – 5.12.2 – 5.13

WELDING PROCEDURE

Form L-2—Sample Welding Procedure Specification

Pass or Weld

Layer(s) Process

Filler Metals Current

VoltsTravelSpeed Joint DetailsDiam.

Type &Polarity

Amps or Wire Feed Speed

Form L-2

Contractor/Organization __________________________________Welding Process(es) ____________________________Type: Manual Semiautomatic

Machine AutomaticTandem Parallel

JOINT DESIGN USEDSingle Double Weld Backing: Yes No Material _______________Root Opening ______ Root Face Dimension ________Groove Angle ___________ Radius (J–U) _________Backgouging: Yes No Method ____________Root Treatment ________________________________

BASE METALSMaterial Spec. _________________________________Type or Grade _________________________________Thickness: Groove ____________ Fillet __________Diameter (Pipe)________________________________

FILLER METALSAWS Specification______________________________AWS Classification _____________________________Manufacturer Trade Name________________________

SHIELDINGFlux ___________________ Mfg. Trade Name_______Electrode-Flux (Class)___________________________Gas Composition ______________________________Flow Rate ______________ Gas Cup Size _________

Identification ___________________________________Revision _______ Date__________ By ____________Authorized by __________________ Date __________Supporting PQR No.(s) __________________________

POSITIONPosition of Groove ______________ Fillet __________Vertical Progression: Up Down ELECTRICAL CHARACTERISTICSTransfer Mode (GMAW): Globular Spray Current: AC DCEP DCEN Pulsed Electrical Stick Out ______________________________Other ________________________________________

TECHNIQUEStringer or Weave Bead __________________________Multi-pass or Single Pass (per side)_________________Number of Electrodes ___________________________Electrode Spacing: Longitudinal __________________Lateral _______________________ Angle__________Interpass Cleaning ______________________________

PREHEATPreheat Temp., Min. _____________________________Interpass Temp., Min.____________________________Interpass Temp., Max. ___________________________

POSTWELD HEAT TREATMENTTemp. _________________ Hold Time_____________Heating/Cooling Rate ____________________________

HEAT INPUTCalculated Heat Input Value: kJ/in kJ/mmMax. Heat Input _________ Min. Heat Input_________


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PROCEDURE QUALIFICATION RECORDPQR NUMBER_________________ (Include PQR Number on All Supporting Documents)

Welder’s Name _____________________ ID________ Welding Test Date ______________________________Process ________________ Position______________ Joint Detail: Fig. 5.1 Fig. 5.2Electrode(s) Mfg. Designation_____________________ Joint Detail: Fig. 5.3 Fig. 5.8AWS Electrode Classification _____________________ Electrical Stick Out ______________________________Flux Mfg. Designation ___________________________ AWS Flux Classification __________________________Postweld Heat Treatment: Temp._______________ Hold Time_______________ Heating/Cooling Rate _________

CurrentDiam. Current WFS* Voltage and Polarity_________ _________ _________ _________ _________

Electrode (1) _________ _________ _________ _________ _________(2) _________ _________ _________ _________ _________(3) _________ _________ _________ _________ _________

Calculated Heat Input (see 5.12) __________________Shielding Gas _________ Dew Point ____________ Flow Rate _____________ Gas Cup Size __________Travel Speed: Min. ___________ Max.____________Base Metal Specification and Thickness_____________ Heat Number __________________________________Backing Metal Specification and Thickness __________ Heat Number __________________________________Base Metal Carbon Equivalent (see 5.4.2) ______________________________________________________________

(Attach Copy of Certified Mill Test Report for Base and Backing Materials)

Preheat Temp._________________________________ Interpass Temp. Min. __________ Max.___________

SPECIMEN TEST RESULTS

All Weld Metal Tension (AWMT) Tensile Strength________________________________________________ksi MPa Yield Strength _________________________________________________

Elongation in 50 mm [2 in] (%) ____________________________________Reduction in Area % ____________________________________________

Visual Inspection: Acceptable Unacceptable **Macro Test: Acceptable Unacceptable

Side Bends 1. ____________ 2. ____________ 3. ____________ 4. ____________

Reduced Section Tension Tension Strength 1. ____________ Location of Break 1. ____________ksi MPa 2. ____________ 2. ____________

Charpy V-Notch Impact ( ___________ , ___________ , ___________ , ___________ , ________ )Toughness of Weld Metal ( ___________ , ___________ , ___________ )SMAW, SAW, FCAW, GMAW—5 Req’d. aAvg. ft·lbs, J ___________ @ ___________ °F [°C]ESW and EGW—8 Req’d. aDiscard the highest and lowest values and average the 3 remaining.

**Chemistry of Deposited Weld Metal C ________ Mn _______ Si ________ P ________ S ___________When Required by Contract Documents* Ni ________ Cr________ Mo _______ V ________ Cu __________

Radiographic Test: Acceptable Unacceptable Remarks: _____________________________________

Fillet Weld Soundness Maximum Size Single Pass: __________ 1.__________ 2.__________ 3.__________Macroetch Minimum Size Multiple Pass: __________ 1.__________ 2.__________ 3.__________

We, the undersigned, certify that the above described WPQR/FWS has been qualified in accordance with Clause 5 of theAASHTO/AWS D1.5M/D1.5, ( __________ ) Bridge Welding Code.

(year)State/3rd Party Witness _________________________ Mfr./Contractor _________________________________Date ________________________________________

Authorized By__________________________________Agency Results Reviewed________________________Date ________________________________________ Date _________________________________________

*Optional **Optional for CJPForm L-3

Form L-3—Procedure Qualification Record (PQR)for Qualification, Pretest, and Verification Results


263

PROCEDURE QUALIFICATION RECORD WORKSHEETPQR NUMBER_________________

Welder’s Name _____________________ ID________ Welding Test Date ______________________________Process ________________ Position______________ Joint Detail: Fig. 5.1 Fig. 5.2Electrode(s) Mfg. Designation_____________________ Joint Detail: Fig. 5.3 Fig. 5.8AWS Electrode Classification _____________________ Electrical Stick Out ______________________________Flux Mfg. Designation ___________________________ AWS Flux Classification __________________________Postweld Heat Treatment: Temp._______________ Hold Time_______________ Heating/Cooling Rate _________

CurrentDiam. Current WFS* Voltage and Polarity_________ _________ _________ _________ _________

Electrode (1) _________ _________ _________ _________ _________(2) _________ _________ _________ _________ _________(3) _________ _________ _________ _________ _________

Shielding Gas _________ Dew Point ____________ Flow Rate _____________ Gas Cup Size __________Travel Speed: Min. ___________ Max.____________Base Metal Specification and Thickness_____________ Heat Number __________________________________Backing Metal Specification and Thickness __________ Heat Number __________________________________Preheat Temp._________________________________ Interpass Temp. Min. __________ Max.___________

State/3rd Party Witness _________________________ Mfr./Contractor _________________________________

Date ________________________________________

Form L-4

Form L-4—Procedure Qualification Record (PQR) Worksheet

Pass Number Layer Process

FILLER METAL CURRENT TEMPERATURE

Diam.Type & Polarity

Wire Feed Speed Amp Volts

Travel Speed

StickOut Preheat Interpass

*Optional

Page ________ of ________

For multiple electrodes list each electrode on separate line. For parallel electrodes show “2 @ ________” under number and diameter.Preheat and interpass temperature measured at mid length of plates approximately 25 mm [1 in] from the weld center line.


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WELDER AND WELDING OPERATOR QUALIFICATION RECORD

Welder or welding operator’s name______________________________________ Identification no. _______________Welding process __________ Manual ________________ Semiautomatic __________ Machine _______________Position _________________________________________________________________________________________(Flat, horizontal, overhead or vertical—if vertical, state whether upward or downward)In conformance with WPS no.________________________________________________________________________Material specification ______________________________________________________________________________Thickness range this qualifies ________________________________________________________________________

FILLER METAL

Specification no. __________________ Classification _____________________ F no. ________________________Describe filler metal (if not covered by AWS specification) _________________________________________________________________________________________________________________________________________________

Is backing used? __________________________________________________________________________________Filler metal diameter and trade name _______________ Flux for SAW or gas for GMAW or FCAW-G____________________________________________ _____________________________________________

VISUAL INSPECTION (6.26.1)

Appearance______________________ Undercut ________________________ Piping porosity ________________

Guided Bend Test Results

Test conducted by ______________________________ Laboratory test no. ______________________________per ______________________________ Test date______________________________________

Fillet Test Results

Appearance___________________________________ Fillet size _____________________________________Fracture test root penetration _____________________ Macroetch ____________________________________(Describe the location, nature, and size or any crack or tearing of the specimen.)Test conducted by ______________________________ Laboratory test no. ______________________________

per ______________________________ Test date______________________________________

RADIOGRAPHIC TEST RESULTS

Test witnessed by ______________________________ Test no._______________________________________per ______________________________

We, the undersigned, certify that the statements in this record are correct and that the welds were prepared and tested inconformance with the requirements of AASHTO/AWS D1.5M/D1.5, ( __________ ) Bridge Welding Code.

(year)

Manufacturer or Contractor _______________________

Authorized By__________________________________

Form L-5 Date _________________________________________

Form L-5—Welder and Welding Operator Qualification Record

Type Result Type Result

Film Identification Results Remarks

Film Identification Results Remarks


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REPORT OF RADIOGRAPHIC EXAMINATION OF WELDS

Project _________________________________________________________________________________________Quality requirements—Section no. ____________________________________________________________________Reported to ______________________________________________________________________________________

WELD LOCATION AND IDENTIFICATION SKETCH

TechniqueSource ________________________________Film to source __________________________Exposure time __________________________Screens _______________________________Film type ______________________________

(Describe length, width, and thickness of all joints radiographed)


(year)

Radiographer(s) _______________________________ Manufacturer or Contractor _______________________

Interpreter ____________________________________ Authorized By__________________________________

Test Date_____________________________________ Date _________________________________________

Form L-6

Form L-6—Report of Radiographic Examination of Welds

Date Weld Identification Area

Interpretation Repairs

RemarksAccept Reject Accept Reject


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REPORT OF MAGNETIC PARTICLE EXAMINATION OF WELDS

Project _________________________________________________________________________________________Quality requirements—Section no. ____________________________________________________________________Reported to ______________________________________________________________________________________

WELD LOCATION AND IDENTIFICATION SKETCH


(year)

Inspector _____________________________________ Manufacturer or Contractor _______________________

Test Date_____________________________________ Authorized By__________________________________

Method of Inspection: Date _________________________________________

Dry Wet Residual Continuous

AC DC Half-wave

Form L-7

Form L-7—Report of Magnetic Particle Examination of Welds

Date Weld Identification Area

Interpretation Repairs

RemarksAccept Reject Accept Reject


267

M1. IntroductionThe AWS Board of Directors has adopted a policywhereby all official interpretations of AWS standardswill be handled in a formal manner. Under that policy, allinterpretations are made by the committee that is respon-sible for the standard. Official communication concern-ing an interpretation is through the AWS staff memberwho works with that committee. The policy requires thatall requests for an interpretation be submitted in writing.Such requests shall be handled as expeditiously as possi-ble but due to the complexity of the work and the proce-dures that shall be followed, some interpretations mayrequire considerable time.

M2. ProcedureAll inquiries shall be directed to the following:

Managing Director, Technical Services DivisionAmerican Welding Society550 N.W. LeJeune RoadMiami, FL 33126

All inquiries shall contain the name, address, and affilia-tion of the inquirer and they shall provide enough infor-mation for the committee to fully understand the point ofconcern in the inquiry. Where that point is not clearly de-fined, the inquiry will be returned for clarification.For ef-ficient handling, all inquiries should be typewritten andshould also be in the format used here.

M2.1 Scope. Each inquiry shall address one single provi-sion of the code, unless the point of the inquiry involves

two or more interrelated provisions. That provision shallbe identified in the scope of the inquiry, along with theedition of the code that contains the provisions or that theinquirer is addressing.

M2.2 Purpose of the Inquiry. The purpose of the in-quiry shall be stated in this portion of the inquiry. Thepurpose can be either to obtain an interpretation of a coderequirement, or to request the revision of a particularprovision in the code.

M2.3 Content of the Inquiry. The inquiry should beconcise, yet complete, to enable the committee to quicklyand fully understand the point of the inquiry. Sketchesshould be used, when appropriate, and all paragraphs,figures, and tables (or the annex), which bear on the in-quiry shall be cited. If the point of the inquiry is to obtaina revision of the code, the inquiry shall provide technicaljustification for that revision.

M2.4 Proposed Reply. The inquirer should, as a pro-posed reply, state an interpretation of the provision thatis the point of the inquiry, or the wording for a proposedrevision, if that is what inquirer seeks.

M3. Interpretation of Code ProvisionsInterpretations of code provisions shall be made by theStructural Welding Committee. The secretary of thecommittee refers all inquiries to the cochairs of the jointAASHTO/AWS subcommittee. The subcommittee re-views the inquiry and the proposed reply to determinewhat the response to the inquiry should be. Following thesubcommittee’s development of the response, the inquiry

Annex M (Informative)

Guidelines for Preparation of Technical Inquiries for the Joint AASHTO/AWS Subcommittee on Bridge Welding


ANNEX M AASHTO/AWS D1.5/D1.5M:2008

268

and the response are presented to the entire StructuralWelding Committee for review and approval. Upon ap-proval by the committee, the interpretation shall be anofficial interpretation of the Society, and the secretarywill transmit the response to the inquirer.

M4. Publication of InterpretationsAll official interpretations shall appear in the WeldingJournal.

M5. Telephone InquiriesTelephone inquiries to AWS Headquarters concerningthe Bridge Welding Code should be limited to questionsof a general nature or to matters directly related to theuse of the code. The Board of Directors’ policy requiresthat all staff members respond to a telephone request foran official interpretation of any AWS standard with theinformation that such an interpretation can be obtained

only through a written request. The Headquarters staffmay not provide consulting services. The staff may,however, refer a caller to any of those consultants whosenames are on file at AWS Headquarters.

M6. The Structural Welding Committee

The Structural Welding Committee’s activities, in regardto interpretations, shall be limited strictly to the Interpre-tation of code provisions or to consideration of revisionsto existing provisions on the basis of new data or tech-nology. Neither the committee nor the staff shall be in aposition to offer interpretive or consulting services on:(1) specific engineering problems, or (2) code require-ments applied to fabrications outside the scope of thecode or points not specifically covered by the code. Insuch cases, the inquirer should seek assistance from acompetent engineer experienced in the particular field ofinterest.


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1. AASHTO Guide Specification for Highway BridgeFabrication with HPS 70W

2. AASHTO Standard Specification for HighwayBridges

3. AASHTO LRFD Bridge Design Specifications

4. AWS D1.3/D1.3M, Structural Welding Code—SheetSteel

5. AWS A3.0, Standard Welding Terms and Definitions

6. AWS A2.4, Symbols for Welding, Brazing, and Non-destructive Examination

7. ANSI Z49.1, Safety in Welding, Cutting, and AlliedProcesses

8. AWS B4.0, Standard for Mechanical Testing ofWelds

9. ASTM A 6/A 6M, Standard Specification for Gen-eral Requirements for Rolled Structural Steel Bars,Plates, Shapes, and Sheet Piping

10. AASHTO M160/M160M, Standard Specification forGeneral Requirements for Rolled Structural SteelBars, Plates, Shapes, and Sheet Piping

11. ASTM E 92, Test Method for Vickers Hardness ofMetallic Materials

12. ASTM E 140, Hardness Conversion Tables for Metals

13. ASTM A 370, Test Methods and Definitions forMechanical Testing of Steel Products

14. AWS A5.25/A5.25M, Specification for Carbon andLow Alloy Steel Electrodes and Fluxes for Electro-slag Welding

15. AWS A5.26/A5.26M, Specifications for Carbon andLow Alloy Steel Electrodes for Electrogas Welding

16. AWS A5.1/A5.1M, Specification for Carbon SteelElectrodes for Shielded Metal Arc Welding

17. AWS A5.5/A5.5M, Specification for Low-Alloy SteelElectrodes for Shielded Metal Arc Welding

18. AWS A5.17/A5.17M, Specification for Carbon SteelElectrodes and Fluxes for Submerged Arc Welding

19. AWS A5.23/A5.23M, Specification for Low AlloySteel Electrodes and Fluxes for Submerged ArcWelding

20. AWS A5.01, Filler Metal Procurement Guidelines

21. AWS A5.18/A5.18M, Specification for Carbon SteelElectrodes for Gas Shielded Arc Welding

22. AWS A5.20/A5.20M, Specification for Carbon SteelElectrodes for Flux Cored Arc Welding

23. AWS A5.28/A5.28M, Specification for Low AlloySteel Filler Metals for Gas Shielded Arc Welding

24. AWS A5.29/A5.29M, Specification for Low AlloySteel Electrodes for Flux Cored Arc Welding

25. ASTM A 435/A 435M, Specification for StraightBeam Ultrasonic Examination of Steel Plates

26. ASME B46.1, Surface Texture (Surface Roughness,Waviness, and Lay)

27. AWS C4.1-G, Oxygen Cutting Surface RoughnessGauge

28. AWS QC1, Standard and Guide for Qualificationand Certification of Welding Inspectors

Annex N (Informative)

Reference Documents


ANNEX N AASHTO/AWS D1.5/D1.5M:2008

270

29. Canadian Standard Association (CSA) StandardW178.2, Certification of Welding Inspectors

30. ASTM E 709, Guide for Magnetic Particle Inspection

31. ASTM E 165, Test Method for Liquid PenetrantExamination

32. American Society for Nondestructive Testing,Recommended Practice No. SNT.TC-1A

33. ASTM E 94, Guide for Radiographic Testing

34. ASTM E 142, Method for Controlling Quality ofRadiographic Testing

35. ASTM E 747, Practice for Design, Manufacture,and Material Grouping Classification of Wire ImageQuality Indicators (IQI) Used for Radiology

36. ASTM E 1032, Test Method for Radiographic Exam-ination of Weldments

37. ASTM E 1025, Practice for Design, Manufacture,and Material Grouping Classification of Hole-Type Image Quality Indicators (IQI) Used forRadiography

38. ASTM A 770/A 770M, Specification for Through-Thickness Tension Testing of Steel Plates for SpecialApplications

39. ASTM A 709/A 709M, Specification for Carbon andHigh Strength Low-Alloy Structural Steel Shapes,

Plates and Bars and Quenched-and-Tempered AlloyStructural Steel Plates for Bridges

40. AASHTO M270/M270M, Specification for Carbonand High Strength Low Alloy Structural Steel Shapes,Plates and Bars and Quenched-and-Tempered AlloyStructural Steel Plates for Bridges

41. ASME Boiler and Pressure Vessel Code, Section V,Article 2

42. The International Institute of Welding (IIW) Ultra-sonic Reference Block

43. ASTM A 108, Specification for Steel Bars, Carbon,Cold-Finished, Standard Quality Grades

44. AWS C5.4, Recommended Practices for Stud Welding

45. AWS Welding Handbook, Volume 1, 8th Edition,Chapter 11

46. ASTM E 23, Standard Methods for Notched Bar Im-pact Testing of Metallic Materials, for Type ACharpy (Simple Beam) Impact Specimen

47. Fracture and Fatigue Control in Structures—Appli-cations of Fracture Mechanics, Barsom and Rolfe,Prentice-Hall Inc.

48. AWS D1.1, Structural Welding Code—Steel


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Commentary on

Bridge Welding Code5th Edition

Prepared by theAWS D1 Committee on Structural Welding

Under the Direction of theAWS Technical Activities Committee

Approved by theAWS Board of Directors



272

AASHTO/AWS D1.5M/D1.5:2008 COMMENTARY

273

Foreword

This foreword is not part of the Commentary of AASHTO/AWS D1.5M/D1.5:2008,Bridge Welding Code, but is included for informational purposes only.

The AASHTO/AWS Bridge Welding Code is produced to provide, to the greatest extent possible, a nationally acceptedsingle source document that may be used as a bridge welding specification by all AASHTO member organizations con-structing steel bridges. Although the proper title for the Bridge Welding Code is the AASHTO/AWS D1.5M/D1.5Bridge Welding Code, it will be referred to as the “code” in this Commentary.

This Commentary has been developed to explain the basis for code provisions, and to provide sufficient information oneach subject to help those involved in bridge construction to effectively use the code.

The beginning of the code was a combination of the ANSI/AWS D1.1-88 Structural Welding Code—Steel and theAASHTO Standard Specification for Welding of Structural Steel Highway Bridges, Third Edition, 1981. Prior to theacceptance of the first Bridge Welding Code, designated ANSI/AASHTO/AWS D1.5-88, all states using Federal Highwayfunds to construct steel bridges were required to use the AWS and AASHTO specifications in concert, as well as any appli-cable FHWA Special Provisions. In addition, many states imposed special provisions of their own.

The primary goals of the code are to (1) ensure a high level of safety in welded steel structures subject to truck or rail-road loads and (2) avoid practices that might reduce the useful life of steel bridges or unnecessarily increase the cost offuture maintenance. Secondary goals include making the specifications more effective in achieving the goals statedabove and the reduction of unnecessary costs.

The goal of improved safety is primarily addressed through improved fracture safety, attained through better specifica-tions for the quality of materials and by the workmanship needed to ensure fracture resistance and good fatigue perfor-mance. Other safety features, for example the avoidance of buckling, are addressed by design specifications andworkmanship tolerances. The goal of reducing unnecessary costs is achieved by specifying only what is necessary toensure safety and good performance, and by providing universal testing procedures to reduce the duplication of effortthat unnecessarily increases the cost of construction.

It is difficult to work with multiple specifications, produced by different groups, sometimes specifying different require-ments for the same task, particularly when published on different schedules. This often inhibits a thorough understand-ing and full utilization of the specifications. When all AASHTO member organizations use the same basic weldingspecification, fabricators, erectors, and inspectors, representing both the Contractor and the Owner, are in a better posi-tion to interpret code provisions properly and to conform to code requirements. When States have the same basicrequirements for essentially the same tasks, better understanding and utilization of the specifications by both Owner andContractor representatives will improve quality while costs are reduced or contained.

Duplication of effort in testing of welders and WPSs is discouraged by the Bridge Welding Committee, AASHTO, andFHWA. Procedures have been developed for the qualification of WPSs with a minimum of complexity and effort, yetwith sufficient detail to ensure reliability.

The Commentary attempts to make clear the reasons for differences that exist between the AASHTO/AWS D1.5 BridgeWelding Code and the AWS D1.1 Structural Welding Code—Steel. The most obvious reason for differences is thatOwners of highway and railway bridges have elected to take steps in the selection of materials and in the qualification

COMMENTARY AASHTO/AWS D1.5M/D1.5:2008

274

and control of WPSs to ensure that all steel bridge members and welds have sufficient toughness to resist brittle fracture.Additional steps are taken in design and construction of bridges to avoid conditions that may lead to hydrogen-inducedor fatigue cracking. The methods used to achieve these goals are based upon the control of welding heat inputs and atten-dant cooling rates, and the minimizing or avoidance of stress concentrations from weld or base metal discontinuities.Control of transformation cooling rates, in addition to control of weld and base metal chemistry, ensures that requiredmechanical properties are obtained in welds and adjacent HAZs. Heat input control, in addition to control of preheat andinterpass temperatures, ensures that the base metal is not degraded as a result of permanent or temporary welds. Thesesame controls provide safeguards against hydrogen-induced cracking.

To date, AWS D1.1 has not incorporated methods of welding heat input control, other than to impose limitations onwelding variables for those WPSs required to be qualified by test, and to specify technique limitations for other WPSsthat are considered prequalified.

Standards necessary to ensure fracture safety in statically loaded structures are less restrictive than those standards nec-essary to ensure fracture safety in cyclically loaded structures. Statically loaded structures, such as buildings, arestressed with variable loadings at relatively slow strain rates. Loadings such as wind loads and floor loads are treated asstatic loads for design purposes. Bridges are cyclically loaded structures, also called dynamically loaded structures, andare stressed with full design forces more frequently, with enough applications of design loading to induce fatigue in themember or component. Strain rates may also be higher in cyclically loaded structures, although a lesser factor in fatiguelife. In bridges and other cyclically loaded structures, live load stresses may initiate or extend fatigue cracks. This israrely a problem in statically loaded structures, or in structures where neither the number of cycles of loading or therange of stress is sufficient to cause fatigue damage.

AASHTO bridges are designed for specific numbers of applications of the design load. Each application and removal ofthe maximum design load produces the design stress range in the bridge member. Fatigue design is based upon the stressrange and the number of cycles of loading.

Fracture safety is important for all metal structures. The underlying principles of metallurgy, fatigue, and fracture are thesame for all cyclically loaded steel structures. In this code, emphasis is placed upon qualification and control of WPSsand avoidance of hydrogen and fatigue cracks.

The safety of steel bridges is largely dependent on resistance to brittle fracture. Fracture is avoided by improving resis-tance to fatigue cracking by minimizing or avoiding stress concentrations in design and construction, and by eliminatingconditions that might cause hydrogen-induced or solidification cracks. Resistance to brittle fracture is significantlyimproved by good weld and base metal toughness, as well as avoiding notches and using good design and details. Thiscode addresses improved workmanship, weld soundness, and fracture toughness to ensure the fracture safety of steel bridgemembers.

Nonredundant fracture critical steel bridge members require a higher level of quality in materials and workmanship toensure safety equivalent to that of redundant bridge members. The 1988 edition of the code made no special provisionsfor the construction of Nonredundant Fracture Critical Members, FCMs. The AASHTO Guide Specification for Non-redundant Fracture Critical Steel Bridge Members was used to construct all FCMs. The Bridge Welding Code was revisedin 1995 to include a Fracture Control Plan.

Since fracture avoidance, particularly avoidance of brittle fracture, is a primary goal of this code, it is helpful to brieflyreview the relationship between workmanship quality, weld and base metal discontinuities, fatigue cracks, toughness,and brittle fracture.

Brittle fracture is the abrupt rupture of a member or component loaded in tension, whether the tension is applied or resid-ual tension, and whether from applied axial or flexural loading. Failure is instantaneous and generally will not arrest ifthe load initiating the brittle fracture is sustained as the fracture progresses. When brittle fracture occurs in a redundantbridge member, the loading is generally transferred to adjacent members and general collapse does not occur. By defini-tion, in nonredundant members, brittle fracture may cause collapse of the structure. Brittle fracture of a tension memberis analogous to buckling of a compression member: rarely will either stop before failure is complete if the loading ismaintained. However, this code does not address buckling of steel bridge members, as buckling is primarily a design ormaintenance consideration. Fracture avoidance is stressed throughout the code because brittle fractures may result fromwhat may have initially appeared to be small, or innocuous discontinuities, prior to fatigue crack initiation and propaga-tion to critical size.


275

The workmanship provisions of the code dictate that notches are to be avoided. Sharp or deep notches are particularlyharmful, whether on the surface or buried within the weld or base metal. Discontinuities at a surface are more criticalthan equivalent discontinuities entirely surrounded by sound metal, but all may cause failure of the part or structure.Standards are established for the soundness of welds that limit the size, location, and sharpness of weld discontinuities.

There is no fatigue crack initiation or propagation without a stress concentration to amplify stress. Stress amplificationby weld or base metal discontinuities is proportional to the size and sharpness of the discontinuity. Cracks are prohibitedbecause they are the sharpest of discontinuities and attract high stress concentrations. The quality of welds specified inClause 3 of the code take this into account, and also provide standards for workmanship and weld soundness that helpensure fracture safety in a bridge fatigue environment.

Under the provisions of this code, weld brittle fracture is avoided through careful attention to items that might reasonablybe anticipated to lead to the initiation of cracks from any source. If hydrogen is properly controlled, although tensile stressand a susceptible microstructure are present, there should be no hydrogen-induced cracking. If proper base metal and weld-ing consumables are used and proper WPSs are followed, there should not be cracking.

Cracks are routinely prohibited by all specifications for welding of steel structures. In addition to prohibiting cracks andcontrolling the quality of workmanship, this code controls the use of temporary welds that may initiate brittle fracture asa result of their hardened HAZs.

Fatigue crack prevention is dependent upon high fracture toughness, good design, and good workmanship that mini-mizes stress concentrations. The maximum crack or discontinuity size that can be sustained by a steel bridge member,subjected to maximum stress at its lowest anticipated service temperature, depends upon the toughness of the steel basemetal or weld metal at the crack tip for the given temperature. AASHTO specifies the minimum fracture toughness ofsteel plates and shapes used to construct bridge members. The minimum toughness of filler metals is specified in thefiller metal specifications, and the toughness of the production weld is specified in the code. Weld and base metalmechanical properties are protected from degradation by code requirements for qualification and control of welding pro-cedures. Good toughness ensures that cracks, created by any condition and possibly extended by fatigue, may grow todiscoverable and therefore repairable size without causing a brittle fracture.

Weld hardness and toughness are dependent upon the chemistry of the base metal and weld metal, the solidificationmechanism affected by cooling rate, and the thermal cycles to which the weld is subjected. HAZ hardness and toughnessare also dependent upon base metal chemistry and thermal cycles. Since base metal chemistry is often more hardenablethan weld metal chemistry, the base metal HAZ may be more sensitive to high cooling rates that cause unacceptablehardening than the weld. The code has been written to protect the hardness and toughness of both welds and HAZs.

Quenched and tempered steels such as AASHTO M270M [M270] (ASTM A 709M [A 709]) Grades HPS 485W [HPS70W], 690 [100], and 690W [100W] steels, and the high strength filler metals used to match the strength of these steels,may have their strength and toughness affected by excessive welding heat input. Unusually slow cooling rates fromexcessive preheat and interpass temperatures, combined with high welding heat inputs, may also degrade the mechanicalproperties of welded joints in these heat treated steels. Fast cooling rates, produced by welding with low welding heatinput, combined with low preheat and interpass temperatures, may produce excessive hardness and hydrogen-inducedcracking in these same high strength steels. Proper procedures for welding quenched and tempered steels are explainedin the Commentary.

Users of the code are encouraged to read all of the code and the Commentary. Together, the two documents are intendedto give a complete picture of bridge welding requirements. However, because many people will not have an opportunityto read the complete code and Commentary before starting to use the code, an attempt has been made to explain eachspecification provision in sufficient detail to make each commentary item self-explanatory. This requires more than adesirable amount of repetition. However, such repetition adds expedience in providing direct and comprehensive clarifi-cation of the potential questions of the user, without having to read the entire document. To completely understand Com-mentary items, the user shall first read the code subclause, figure, etc. upon which the Commentary is based. Code text isnot repeated in the Commentary.

The Commentary is an informative addition to the Bridge Welding Code. Its purpose is to explain, provide history, andto educate. No statement in the Commentary modifies the code or is binding upon code users in the absence of specificcode provisions. Each subclause in the code does not require a comment. Where individual specifications are consideredself-explanatory and fully understood, no commentary is provided. The principles of welding and fracture avoidance are


276

emphasized to a greater extent than provisions for mechanical testing of welds or NDT, which are not new material inthis code.

All references to numbered subclauses, tables, figures etc. shall, unless otherwise indicated, refer to the identically num-bered subclause, table, or figure in the Bridge Welding Code, AASHTO/AWS D1.5. References in the Commentary areprefixed with a “C-” to indicate they are commentary material. Annexes of the code also use the prefix “C-” to designateparagraphs and figures.

Normative annexes are a part of the code. The code also contains useful but informative information that is provided toassist users of the code. This information is contained in both normative and informative annexes that use alphabet lettersA, B, C, and so forth. Annex J, Description of Common Weld and Base Metal Discontinuities, is provided to help codeusers to identify, describe, and evaluate common weld and base metal discontinuities.

Code writing is a continuing process. Provisions that code users feel should be corrected or improved should be called tothe attention of the AASHTO/AWS Bridge Welding Committee (see Annex M).


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C-1.1 Application

This AASHTO/AWS Bridge Welding Code is specifi-cally written for the use of states, provinces, and othergovernmental members associated with AASHTO. Otherorganizations that have a need to construct welded steelbridges to support dynamic loads should study the rela-tionship between the fatigue loads imposed on their struc-ture and the design truck loads and number of cyclesprovided for in the AASHTO Standard Specification forHighway Bridges.

The AASHTO/AWS Bridge Welding Code, AASHTO/AWS D1.5, is referred to as “the code” throughout thetext of the Bridge Welding Code and this Commentary.The AWS D1.1, Structural Welding Code—Steel, andother specifications of the American Welding Societyalso frequently use the term “code” when referring toprovisions of individual specifications. Care should betaken to avoid confusion in the use of this common term.When the term “code” is used in the Bridge WeldingCode and this Commentary, it only refers to theAASHTO/AWS D1.5 Bridge Welding Code.

C-1.1.1 This code specifies the material and workman-ship requirements necessary to construct welded steelhighway bridges. Specifications are provided for theNDT of welds and base metal, when required by the codeor contract documents, or when ordered by the Engineer.The design of bridges is not described in the code. Thisinformation is specified in the AASHTO Standard Spec-ifications for Highway Bridges or the AASHTO LRFDBridge Design Specifications.

C-1.1.2 The quality of workmanship described in thecode is based upon what was once called “good practicein a modern bridge shop.” The code is a “workmanship”specification, meaning the quality required is based uponwhat is readily achievable. “Suitability for service” is theminimum quality required for the member or weld toperform its intended function.

The Engineer may specify or accept workmanship andweld quality standards that are different than thosedescribed in the code. Workmanship and weld qualitystandards that differ from code requirements should bespecified in the contract documents so there is no need tonegotiate the cost of additions or deletions to the workduring fabrication or erection.

Experience has shown that the quality of thermal cut sur-faces, welds, and the effects of other fabrication practiceson workmanship and finish can affect bridge fatigue life,safety, and the extent of future maintenance. In somecases, the quality of a completed production weld maynot meet all the requirements of the code. The Engineermay also use engineering judgment to accept the qualityof the weld as completed, or with modified repairs.When such judgment is used, evaluation of suitability ofservice using modern fracture mechanics techniques, ahistory of satisfactory service in similar structures, orexperimental evidence is recognized as a suitable basisfor alternate acceptance criteria. Unnecessary and/orimproper repairs made by welding may cause more seri-ous discontinuities, distortion, and cracks.

C-1.1.3 The Engineer is the individual with the authorityto approve shop drawings, materials, WPSs, modifications

Commentary on

Bridge Welding Code

C-1. General Provisions


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to the requirements of the contract documents, and othermatters that require approval of the agency represented.The Engineer is considered to be the Owner or Owner’srepresentative, and may delegate this authority to others.

C-1.1.4 Contractor. “Contractor” is the proper term forthe person or firm that is responsible for performing thework as described in the code. However, when the workis expected to be done in a bridge fabricating shop, theterm “fabricator” may be used interchangeably. Whenwork is expected to be done in the field, the term “erec-tor” may be used instead of Contractor.

C-1.2 Base MetalC-1.2.1 Specified Base Metal. The code lists AASHTOapproved base metals in 1.2.2. AWS D1.1 lists other car-bon and low alloy steels that are weldable. The contractdocuments may specify any steel product that the Engi-neer considers suitable for the intended purpose. Engi-neers should specify, when possible, only listed steels,and if not, only steel products known to be weldable. Asteel is considered weldable when it can be joined bywelding without unusual difficulty. The steel specifiedshould also be readily available for purchase.

Structural steel plates and shapes are subject to thedelivery requirements of AASHTO M160M [M160](ASTM A 6M [A 6]) as provided in the AASHTOM270M [M270] (ASTM A 709M [A 709]) base metalspecifications. Dimensional tolerances, allowable disconti-nuities, and methods of conditioning (repairing) in the millare as described in the delivery requirements. If there arespecial requirements for straightness, surface finish, over-run or underrun in thickness, restrictions on conditioningby welding at the mill, or any other project specific require-ments, they should be specified in the contract documents.Provisions for the repair of base metal is described in 3.2.

The dimensional tolerances for fabricated structural steelare as described in Clause 3 of this code and are indepen-dent of base metal delivery requirements. In some cases,AASHTO M160M [M160] (ASTM A 6M [A 6]) milltolerances will exceed those applicable for bridge con-struction, in which case it may be necessary to correctthe material deficiency or to replace the material.

C-1.2.2 Approved Base Metals. The base metals listedare steels approved for use in welded steel bridge con-struction. The list is reviewed periodically and additionsmay be made to the list as approved by AASHTO. Eachsteel product, plate, shape, bar, etc., is described by theAASHTO materials specification designation and corre-sponding ASTM (American Society for Testing andMaterials) specification.

M270M [M270] steels of a designated grade are essen-tially the same as ASTM A709M [A709] steels of thesame grade. AASHTO M270M [M270] (ASTM A 709M[A 709]) steels are enhanced versions of the structuralsteels used in buildings and other steel structures. Theprincipal enhancement is in the area of toughness, withoptional provisions applicable to Fracture Critical Mem-bers. Common ties exist between the following steel des-ignations:

(1) Grade 250 [36] ASTM A 36M [A 36]

(2) Grade 345 [50] ASTM A 572M [A 572],Grade 345 [50]

(3) Grade 345W [50W] ASTM A 588M [A 588],Grade 345 [50]

(4) Grade 690 [100] ASTM A 514M [A 514]

(5) Grade 690W [100W] ASTM A 514M [A 514]

Base metal toughness is a supplemental requirement ofthe AASHTO and ASTM steel specifications. Fillermetal toughness is a requirement of the AWS electrodeclassifications described in this code. If indicated by thecontract, approved base metals are to conform to theminimum CVN test values specified by AASHTO for thetemperature zone in which the bridge will be located.Weld metal CVN test value requirements are describedin Tables 4.1 and 4.2, based upon AASHTO Tempera-ture Zone I, II, or III.

C-1.2.3 Thickness Limitations. The thickness limita-tions of this paragraph deal only with minimum thick-ness. This code provides basic welding specifications forsteel thicknesses equal to or greater than 3 mm [1/8 in].Proper controls should be exercised over welding heatinput, preheat and interpass temperature depending uponsteel thickness and the relative configuration of the thick-nesses of the joint.

For sections thinner than 3 mm [1/8 in], AWS D1.3/D1.3M, Structural Welding Code—Sheet Steel, shouldbe consulted. However, this document is based uponstatic applications, and does not contain special provi-sions specific to bridge welding.

The maximum material thickness for steel governedunder AASHTO M270M [M270] (ASTM A 709M[A 709]) is 100 mm [4 in]. However, the majority of thecurrent code provisions were drafted based upon steelspecifications not subjected to this maximum thicknesslimit. The Engineer should decide if maximum thick-nesses limitations other than 100 mm [4 in] should beused, and specify any special welding requirements forheavier plates in the contract documents.


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C-1.3 Welding ProcessesC-1.3.1 A major difference between this code and AWSD1.1 for welding primary (designed) members and con-nections is that only WPSs using listed SMAW elec-trodes with a specified minimum yield strength less than620 MPa [90 ksi] (E70, E80, and E90) are to be consid-ered prequalified and exempt from testing in this code(see also C-1.3.6 and C-1.8). Other WPSs for primaryconnections are to be qualified as described in Clause 5.Low and intermediate strength SMAW WPSs are exemptfrom testing when using the current range recommendedby the manufacturer since extensive experience hasproven such WPSs are acceptable. SMAW has a recordof proven service performance over a wide range ofWPSs for the steels listed.

All SMAW is to be performed with low hydrogen elec-trodes under the provisions of this code. Low hydrogenelectrodes require a short arc length to ensure properoperation and effective shielding. Proper welding tech-nique can be verified by observing the arc and the qualityof the finished welds. WPSs utilizing standard details ofwelded joints as described in Clause 2, or nonstandardjoint details are qualified by WPS qualification testing asdescribed in 5.7.7 (see also 2.6.1 and 5.13).

C-1.3.2 FHWA-sponsored research dedicated to improv-ing the fracture toughness and fatigue performance ofESW welds has been completed. Efforts are now under-way to seek AWS/AASHTO approval of ESW of buttjoints in redundant tension and reversal members whennarrow gap ESW WPSs are qualified by test. Narrow gapESW (NGI-ESW) WPSs, developed as a result of FHWAresearch, produce sufficient notch toughness and excel-lent weld soundness.

The results of the FHWA research project are docu-mented in FHWA Report No. “FHWA/RD-87/026—Improved Fracture Toughness and Fatigue Characteris-tics of Electroslag Welds” published in October 1987. Toassist the industry in implementing the results of theresearch, FHWA also published the following docu-ments, which were prepared from information containedin the research report:

(1) FHWA Report No. FHWA-SA-96-053, TechnicalInformation Guide for Narrow-Gap Improved Electro-slag Welding. This document was prepared for weldingand metallurgical engineers. The document contains sci-entific and technical information about variables of theNGI-ESW process, and microstructure and properties ofthe weld and HAZ to improve toughness of ESW joints.

(2) FHWA Report No. FHWA SA-96-052, ProcessOperational Guide for Narrow-Gap Improved Electro-slag Welding. This document for welding engineers,

operators, inspectors and supervisors who use NGI-ESWto build steel bridges. The document presents the mini-mum technical information necessary for understandingand using NGI-ESW procedures.

(3) FHWA Report No. FHWA-SA-96-051, TrainingManual for Narrow-Gap Improved Electroslag Weldingfor Bridges. This document was prepared for ESW oper-ators, welding supervisors and shop inspectors. It repre-sents a step by step procedure for assembling andwelding structural members of bridges using the NGI-ESW process.

(4) FHWA Report No. FHWA-SA-96-050, D1.5Bridge Welding Code Proposed Revisions to IncludeNarrow-Gap Improved Electroslag Welding. This docu-ment contains the proposed changes to AASHTO/AWSD1.5 to reflect new developments in ESW technology.

All of the above documents and reports are availablefrom the National Technical Information Service,Springfield, VA 22161, www.ntis.gov.

C-1.3.4 Short circuiting GMAW-S is restricted for theconstruction of steel bridge members because of its pro-pensity to form fusion discontinuities called cold laps.Properly qualified GMAW WPSs, operated in the sprayor globular mode of metal transfer are allowed (see4.14.4). Also see Annex C for a description of GMAW-S.

C-1.3.5 Welding processes that are not listed in the codemay be used with the approval of the Engineer. Anywelding process and WPS that provides for the use ofthat process may be used, provided the specific weldjoint details and controls of welding variables that havebeen qualified by tests are acceptable to the Engineer.Consideration of welding processes not described in thecode is allowed, but acceptance by one agency does notobligate other agencies to approve use of the process.

C-1.3.6 Welding of Ancillary Products. This provisionwas added to the 1995 code to allow the fabrication ofthe listed items and similar items, as determined by theEngineer. Such items are not usually subjected to designtensile stresses and may not be welded to the tensilestress region of stress-carrying members. In addition tothe prequalification of SMAW WPSs, the requirementfor full WPS qualification is also relieved for SAW,FCAW, and GMAW processes when used to weld thesemembers, provided the manufacturer’s recommendationsfor WPS variables are followed, and the other portions ofthe code are satisfied. When a product deemed ancillaryby the Engineer is welded to the compression region of astress-carrying member, then the full requirements ofWPS qualification need to be satisfied for the welds con-necting the product to the stress-carrying member.


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C-1.8 Standard Units of Measurement

D1.5 has two units systems: metric and U.S. Customary.Throughout the code, the user will find dimensions in SI(metric) Units followed by U.S. Customary Unitsin brackets [ ]. The U.S. Customary Units are “hard”conversions of the SI Units; that is, each is a carefullyconsidered rational value, as opposed to a “soft” conver-sion value that has been simply adjusted from the SIvalue using a conversion factor. For example, the softconversion of 25 mm would be 0.984 in, and the hardconversion would be 1 in. It is inappropriate to pick andchoose between SI and U.S. Customary tolerances; eachsystem of units should be used as a whole, and the sys-tem used should be the same as that used in the shopdrawings.

In terms of WPSs, fabricators should not be required torerun PQRs for a change in units. However, WPSsshould be drafted in the appropriate units.

C-1.9 Welding Procedure Specifications (WPSs)

Each weld is to be made using an approved WPS, whichis based on a PQR. The results of mechanical tests of

weld specimens verify that the strength, ductility andtoughness required by the code have been produced inthe test welds. Welding in conformance with the provi-sions of an approved WPS, which is in turn based uponan approved PQR, provides assurance that productionwelds will have the strength, ductility and toughnessrequired by the code.

Two exceptions are made to this general requirement:

(1) SMAW that has a minimum specified yieldstrength less than 620 MPa [90 ksi] may be used withoutqualification testing, provided the WPS conforms to themanufacturer’s recommendations for weld variables, andthe welding is to be done in conformance with the provi-sions of Clause 4, Part B (see 5.1.1).

(2) Ancillary product welding is exempted from test-ing per 1.3.6.

C-1.10 Mechanical Testing

AWS B4.0 or B4.0M, Standard for Mechanical Testing ofWelds, is to be the standard for test apparatus and testspecimens. In areas where the provisions of B4.0 orB4.0M and the Bridge Welding Code conflict, this codeshould take precedence.


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C-2.1 Drawings

C-2.1.1 The drawings referred to in the code include thebridge design drawings or plans and the shop or workingdrawings. Plans, along with specifications and specialprovisions, are prepared by the Engineer or Owner, shopdrawings are prepared by the Contractor. The plans andshop drawings should describe the required welds bywelding symbols or a combination of welding symbolsand notes.

The Engineer is encouraged not to detail specific grooveweld details for routine welds, but to simply specify thejoint penetration (CJP or PJP weld), joint type (butt joint,tee joint, corner joint, etc.), and weld size as necessary.The specific joint details are left to the Contractor. TheContractor, assumed knowledgeable in welding andwelding economies, is in the best position to select thedetails for the welded joints that best fit the Contractor’scapabilities and avoid undesirable effects such as exces-sive distortion.

All approved CJP groove weld joint details produce thesame weld joint strength, when welded with the samestrength filler metal. Unless there is justification to spec-ify a particular process or groove weld configuration, theContractor should be allowed to determine details duringthe preparation of shop drawings. Assuming an appro-priate prequalified SMAW WPS or qualified WPS isused, the details of welded joints provided in Figures 2.4and 2.5 are considered standard and therefore exemptfrom testing, based upon a long history of successfulperformance during welding and in service. The Con-tractor may propose other joint details that are qualifiedby tests described in 5.7.7, and the Engineer mayapprove the joint detail based upon weld joint qualifica-tion testing.

C-2.1.2 The volume of weld metal deposited and thenumber of weld passes on the first side of a two-sidedgroove weld joint, before welding the second side, maysignificantly affect angular distortion. The second side ofthe weld joint may need more weld metal than the firstside to overcome the distortion produced by shrinkage ofthe first side weld. Special weld pass sequencing is gen-erally not placed on the plans, but should be included inthe WPS and/or on the shop drawings.

Both the Engineer and the Contractor should makeefforts to minimize the size of groove welds where possi-ble. This may be done by controlling groove angles androot openings. Groove details should be primarilydesigned for adequate access for welding and visualinspection, as well as the minimum volume of weldmetal, as any excess beyond the minimum will createunnecessary distortion and residual stresses, and maycause lamellar tearing in corner and T-joints.

Residual stresses may be reduced by minimizing the vol-ume of weld metal and by lowering the yield strength ofthe weld metal to the minimum strength acceptable forthe design. Undermatching of weld metal strength isencouraged for fillet welds that are designed to transmitonly shear stress (see Notes to Tables 4.1 and 4.2).

Some welded joint configurations for corner and T-jointscontribute more than others to the risk of lamellar tear-ing, cracks parallel to the plate surface caused by highlocalized through-thickness strains induced by thermalshrinkage. The capacity to transmit through-thicknessstresses is essential to the proper functioning of somecorner and T-joints. Laminations (pre-existing planes ofweakness in the base metal) or lamellar tearing may impairthis capacity.

Consideration of the problem of lamellar tearing includesdesign aspects and WPSs that are consistent with theproperties of the connected material. In connectionswhere lamellar tearing might be a problem, considerationshould be given in design to maximum component flexi-bility and minimize weld shrinkage strain.

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Observing the following precautions may reduce the riskof lamellar tearing during fabrication in highly restrainedwelded connections:

(1) On corner joints, where feasible, the bevel shouldbe on the through-thickness member.

(2) The size of the weld groove should be kept to aminimum consistent with the design, and unnecessarywelding should be avoided.

(3) Subassemblies involving corner and T-jointsshould be fabricated completely prior to final assemblyof connections. Final assembly should preferably be atbutt joints.

(4) A predetermined weld sequence should beselected to minimize cumulative shrinkage stresses onthe most highly restrained elements.

(5) Undermatching using a lower strength weldmetal, consistent with design requirements, should beused to allow higher strain in the weld metal, reducingstress in the more sensitive through-thickness directionof the base metal (see Notes to Tables 4.1 and 4.2).

(6) “Buttering” with low strength weld metal, peen-ing, or other special procedures should be considered tominimize through-thickness shrinkage strains in the basemetal.

(7) Material with improved through-thickness ductil-ity may be specified for critical connections.

In critical joint areas subject to tensile loading in thethrough-thickness direction, material should be UTinspected (straight beam) within a lateral distance oftwice its thickness from the joint to ensure the absence ofexisting laminations and significant discontinuities suchas metallic and nonmetallic inclusions. In addition, thefollowing precautions should be taken:

(1) The Engineer should selectively specify UTinspection, after fabrication or erection or both, of spe-cific highly-restrained connections critical to structuralintegrity that could be subject to lamellar tearing.

(2) The Engineer may consider whether minor welddiscontinuities or base metal imperfections can be leftunrepaired without jeopardizing the structural integrity,since gouging and repair welding will add additionalcycles of weld shrinkage to the connection, and mayresult in the extension of existing flaws or the generationof new flaws by lamellar tearing.

(3) When lamellar tears are identified and repair isdeemed advisable, a special WPS or a change in jointdetail may be necessary.

C-2.1.3 Partial joint penetration (PJP) groove welds arelimited to joints designed to transmit compression in buttjoints with full-milled bearing surfaces, and to cornerand T-joints (see 2.14). PJP groove welds also may beused in nonstructural appurtenances such as ancillaryproducts. In butt joints, they may be used to transmitcompressive stress, but should never be used to carrytensile stress in bridge members because of short fatiguelife. When PJP groove welds are to be used, the effectiveweld size (E) should be specified on the plans, and theContractor provides the groove preparation necessary toproduce the required weld size.

Longitudinal web-to-flange welds designed for tensilestresses parallel to the weld throat have the same allow-able fatigue stress range whether designed as a fillet weldor a CJP groove weld with backing removed. PJP groovewelds and CJP groove welds with backing remaining inplace have a lower allowable fatigue stress range. Thesame is true for similar welds carrying tension parallel tothe weld throat, as long as the weld axis or weld throat isparallel to the applied stress. This is independent of thefact that the weld may be part of a member that is subjectto considerable axial tensile stress and stress range, forexample an axially stressed box section, as long as thebox is not designed for torsion about its longitudinalaxis. For shear stresses, the AASHTO Specification pro-vides allowable stress ranges for fillet welds only.

There will be no increase in bridge safety as a result ofspecifying CJP groove welds where PJP groove welds orfillet welds, at considerably less cost, will carry thedesign stress. Smaller weld volumes, consistent withdesign stress requirements, create less residual stress andless chance that there will be unacceptable distortion orlamellar tearing. However, the minimum size for filletwelds and PJP groove welds, relative to the thickness ofthe materials, is also necessary to ensure adequate heatinput for full fusion and adequate cooling rates (seeTable 2.1 for fillet welds and Table 2.2 for PJP groovewelds).

C-2.1.3.1 AWS A2.4, Standard Symbols for Welding,Brazing, and Nondestructive Examination, should be usedto specify welds using industry standard methodology(see 1.5).

C-2.1.5 All requirements for special inspections or NDTnot covered by this code need to be specified in the con-tract documents. This ensures that required inspectionsand tests will be performed, avoiding disagreement overminimum weld quality and additional costs (see 6.6.5).

C-2.1.6 AASHTO design specifications allow the use ofundermatching weld metal strength for the applicationslisted in this paragraph. The most common applicationfor undermatching weld metal strength is on higher


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strength steel (e.g., M270M Grade HPS 485W [HPS70W] and 690/690W [100/100W]), and for fillet weldsand PJP groove welds loaded in shear. It is essential thatthe designer of the weld consider the strength of the weldmetal that is used when determining the required weldsize. In most cases where undermatching is permissible,it offers the benefits of reduced residual stresses andgreater resistance to cracking. The code provides theoption for the Engineer to specify matching weld metal,specify undermatching weld metal, or to provide theoption to the contractor to utilize either approach. Whenthe option is given to the contractor, the design drawingsneed to show the required weld size for each filler metalstrength level.

In most cases, E70 or E80 weld metal will be used forundermatching applications. E70 is generally preferable,but E80 is often required because, when atmosphericcorrosion resistance is required for weathering steels, theadded alloys result in E80 strength class weld metal.

Shop drawings are required to show the required weldsize, and the required weld strength. To avoid confusionon the shop floor, options should not be shown on shopdrawings. If no weld metal strength class is designated,matching weld metal is assumed.

C-2.2 Basic Unit StressesBased on AASHTO specifications, the Engineer deter-mines the unit stresses to be used as a basis for design.

C-2.3.1 Groove Welds. The effective groove weld sizewas formerly called the effective throat. The effectivethroat⁄effective size of PJP groove welds is defined in2.3.1.3, and further detailed and explained in Annex A.The effective size of CJP groove welds is as described in2.3.1.2.

C-2.3.1.3 The effective PJP groove weld size is basedupon the geometry of the groove weld joint preparation,the welding process, and welding position. Access forwelding at the root of bevel or V grooves and an assumedrelative depth of joint penetration is attributed to the var-ious welding processes. It is assumed that penetration tothe root is achieved for SMAW, SAW, GMAW, FCAW,ESW, and EGW processes when the groove angle equalsor exceeds 60°.

Depth of penetration in arc welding is affected bypolarity, current, and current density. Penetration isincreased by welding electrode positive. In GMAW andFCAW-G, the depth of penetration is also affected by thechoice of shielding gas. WPSs for any process designed

for vertical-up progression generally have much deeperpenetration than the same process operated vertical-down. Only vertical-up welding is allowed by the code,unless qualified by tests and allowed by the Engineer.

All PJP V and bevel groove welds are subject to incom-plete fusion at the root. The amount of incomplete fusionmay vary, depending on welding conditions. Assembledwith zero root opening, as the included angle of thesegroove welds decreases, the expected size of the fusiondefect at the root increases. PJP details for V- and bevel-grooves assume a depth of penetration that is 3 mm[1/8 in] greater than the required weld size whenever theincluded groove angle will be less than 60°, unlesswelded with SAW.

When nonstandard PJP groove weld details are proposedby the Contractor, the Engineer should require evidenceby testing that the required weld sizes will be routinelyproduced by the selected WPS. Macroetched sectionscan be used to demonstrate that the required penetrationand fusion at the weld root can be routinely achievedusing the given WPS (see 5.7.7).

C-2.3.1.4 Flare groove welds, a form of PJP grooveweld, are not used in bridge construction because thecurved groove configuration provides poor accessfor welding at the root. With poor root access, there isa greater chance of producing fusion discontinuities.In thick sections, a flare groove is uneconomical andimpractical.

C-2.3.2.3 The provision for minimum fillet weldlength establishes good weld design proportions. Theminimum length is based upon the minimum required forthe fillet welds to effectively and reliably transfer loads.It also ensures that the welding arc is established longenough to produce sound welds and minimizes excessivehardening of the HAZ. This length requirement is tied tolimitations on minimum groove and fillet weld sizes (seeTables 2.1 and 2.2).

C-2.3.3 Plug and Slot Welds. Plug and slot welds com-pletely fuse the interface between adjacent parts withinthe area described by the hole or slot. Plug and slot weldsshould not be confused with fillet welds within a hole orslot. These are different types of welds, made by differ-ent procedures, and may have significantly differenteffective areas or sizes for a given hole or slot. Plug andslot welds should only be used for transmitting shearstresses.

There is a higher risk of discontinuities in plug and slotwelds when compared with fillet welds. Plug and slotwelds are extremely susceptible to slag inclusions andfusion discontinuities that can lead to fatigue cracks.Plug and slot welds should be avoided, and are prohib-


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ited in members subject to tension and reversal of stress[see 2.14(6)]. The risk of cracking can be reduced throughspecial techniques, but plug and slot welds are inspectedby RT or UT.

Often, high-strength bolts can perform the same designfunction as plug and slot welds with less adverse effecton fatigue life.

C-2.3.4 Welds in corner and T-joints are required to havereinforcing fillet welds where allowed by the geometryof the connected parts (see Figures 2.4 and 2.5, Note 6).In the calculation of weld size, PJP groove welds aregiven credit for the reinforcing fillet welds, but CJPgroove welds are not given credit unless undermatchedweld metal is used. The reason for this disparity is thatthe design cannot give extra credit for welds that arebuilt-up to be stronger than the parts they join.

C-2.4 General

Because bridges are cyclically loaded structures, fatigueis an important design consideration. Fatigue is the resultof repeated local plastic (inelastic) deformation. Withenough cycles of such deformation, fatigue cracks caninitiate and propagate. In some cases, stresses resultingfrom applied loads are elastic in a global sense, but local-ized areas may exist where the stresses concentrate orcombine with internal stresses and exceed the yieldstrength of the metal. In welded construction, two factorscan cause this to occur: stress concentrations and residualstresses.

Stress concentrations can occur due to geometricchanges in a member and discontinuities in the basemetal or weldment. There are many examples of geomet-ric changes, some of which include changes in widthand/or thickness of flange plates, welded cover platesand even reinforcement of a groove weld joining platesof similar sizes. Discontinuities can include laminationsand nicks as well as cracks, porosity, incomplete fusion,and slag inclusions in welds. In some cases, the orienta-tion of an imperfection can determine how severely itaffects the member. This is why base metal laminationsparallel to the direction of applied stress are acceptablewithin certain limitations.

Residual stresses also affect fatigue performance. Resid-ual stresses exist in any welded structure due to shrink-age during cooling of the weld. This can be a particularconcern in welding highly restrained members. Eventhough the stress resulting from applied loads to awelded member may be within the elastic range, the

added effect of the residual stresses may result in aninelastic level at the welds.

AASHTO design specifications require that both thestatic strength and the fatigue strength be considered indesign. The allowable fatigue stress ranges are basedupon full scale testing of as-welded components that rep-licate typical bridge details. These allowable stressranges have incorporated the effects of geometric stressconcentrations, allowable discontinuities, and residualstresses. Welded connections and connection details areto comply with these design parameters.

Part BStructural Details

C-2.5.1 Filler plates have a long history of use in bridgesconstructed with riveted and bolted joints. When fillerplates are used to make welded connections in memberssubject to tension and reversal of stress, the fatigue lifeof the member may be reduced. A filler plate is part of awelded connection and shown on the design drawings.Filler plates are categorized into two groups, those lessthan 6 mm [1/4 in] thick and those 6 mm [1/4 in] thick orgreater in thickness.

C-2.5.2 Filler plates less than 6 mm [1/4 in] thick arerestricted to the area between the adjacent parts, notintruding into the weld area. These may be used to sepa-rate adjacent parts and to provide backing by weldingover the edge of the filler plate, just as root openings arespanned by welding against steel backing in web-to-flange and similar connections. Because small fillerplates simply displace parts and carry no stress, the weldsize is increased to compensate for the thickness of thesefiller plates and designed to carry the complete load.

C-2.5.3 When filler plates are 6 mm [1/4 in] or greater inthickness, the strength is developed by the welds on theperimeter. Filler plates of this type are not treated likethin filler plates. When two adjacent parts, A and B, arejoined by welding and the connection includes a thickfiller plate, the weld between A and the filler plate fullydevelops the maximum load on the connection, and theweld between the filler plate and B does the same. Inaddition to carrying the direct stress applied to the mem-bers, the welds have sufficient capacity to provide forany eccentricity created by the placement of the fillerplates in the space between connected parts.


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C-2.6 PJP Groove WeldsIf PJP welds in butt, corner, or T-joints are subjected tocyclic tensile stresses normal to the effective weld throat,fatigue cracks may initiate at the weld root and propagateinto the weld joint. The fatigue life of such joints wouldbe relatively short, but typically the stress range wouldbe very low.

When the unwelded portion of a PJP groove weld is paral-lel to the applied stress, there is no stress concentration.Except for CJP groove welds, all longitudinal welds thatjoin the web to the flange in bridge members haveunwelded portions. This applies to both fillet and PJPgroove welded joints. Fillet welded connections have anunwelded portion between the fillets on each side of theweb. PJP groove welds have an unwelded portionbetween the roots of the welds. The unwelded portions ofwelded joints subject only to shear stress parallel to theeffective weld throat have little adverse effect on fatiguelife. This statement assumes, of course, that the welds aresound, regardless of joint configuration.

The code does not restrict the use of PJP groove weldsfor corner and T-joints where the applied stress is limitedto shear parallel with the weld axis. Any welded connec-tion made using a PJP groove weld or a fillet weld fromone side only and loaded in a direction normal to the axisof the weld, is to have the connected parts restrained sothat rotation or dislocation of the connected parts doesnot concentrate tensile stress at the unwelded root of theweld.

Part CDetails of Welded Joints

C-2.7.1 Because these details have a long history of sat-isfactory use in welding and in service, the details ofwelded joints shown in Figures 2.4 and 2.5 are consid-ered standard, and the joint designs are exempt from test-ing when SMAW, SAW, GMAW, and FCAW areperformed in conformance with code requirements, andwhen an appropriate WPS is used. Their use requiresconformance with 2.9 and 2.10 and the details of thewelded joints shown in Figure 2.4 or 2.5.

The essentials of good weld joint design are as follows:

(1) Provide good access to all parts of the weld jointduring welding to ensure that good penetration andfusion is possible, and

(2) The joint uses only the minimum amount of weldmetal necessary to produce sound welds of the requiredstrength, and

(3) The joint uses weld metal placed in a manner thatminimizes angular distortion and residual stresses (seeC-2.1.1 and C-2.1.2).

Although the standard joint details may be used to makesound welds, the availability of these joint details doesnot mean that no other joint details can produce accept-able results. Many nonstandard welded joint detailsacceptable for specific applications may be less costly toprepare and weld and may reduce distortion or the risk oflamellar tearing. Many standard joint details, because ofconcern about sufficient access for welding, requireexcessive weld metal. Joint details that have a radius atthe root and a small included angle may be preferredover details that have a large included angle simply toprovide access at the root. Roots of welds may be gougedand/or ground after fitting to provide the required rootradius.

Joint details that do not conform to the details shown inFigures 2.4 and 2.5 are considered nonstandard, andqualified by test as described in 5.7. Test Plate C, Figure5.3, is a generic representation of a plate used to qualifynonstandard joint details. The costs of such tests areborne by the Contractor. Testing and approval of non-standard joint details may provide cost savings and/oravoid fabrication problems (distortion, restraint cracks,etc.). The Engineer should approve new and nonstandardjoint details based upon these tests that prove that thejoint’s configuration allows the production of soundwelds. Acceptance should also take into account knowl-edge of welding conditions, visual inspection and NDT,that when performed in production, will give confidencein the required weld quality.

C-2.8.1 The mechanical properties of fillet welds areevaluated by testing groove welds as described in 5.10.Fillet welds joining perpendicular components are identi-cal to root passes in groove welds where the includedangle is 90°. If the access and orientation of the partsbeing joined is acceptable, welding may be done success-fully using SMAW, SAW, GMAW, or FCAW WPSs.

C-2.8.1.1 There is a direct correlation between weldsize and heat input. Insufficient heat input or too low apreheat temperature for the thickness of the steel to bewelded can cause unacceptable hardening of the weld orHAZ due to the rapid cooling of small welds. Unaccept-able hardening may contribute to embrittlement. Weldmetal embrittlement is less common, especially in lowerstrength electrodes, because the filler metal generally hasless carbon and therefore is less hardenable than the basemetal.


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Small fillet welds, particularly on thick, insufficientlypreheated steel, are potential crack initiation sites. Forthis reason, small cosmetic welded repairs should beavoided. When repairs are essential, welding should bedone in conformance with the provisions of an approvedWPS that provides adequate preheat.

Small reinforcing fillet welds for corner or T-joints maybe made integrally with the much larger groove welds orlater as separate welds. Single-pass fillet welds not madeas an integral part of much larger welds are to conform tothe minimum size requirements of Table 2.1, with thepreheat and interpass temperatures conforming to 4.2.

C-2.8.1.2 The maximum fillet weld size is based uponthe ability to make sound welds while protecting theedge of a relatively thin material that is to receive a filletweld along its edge. The part edge is melted and some-times destroyed by the concentrated heat of the weldingarc. This is not necessarily an indication of poor work-manship. Without proper controls, a weld on a relativelythin edge that has been melted away may have less effec-tive size than it appears, and the effective weld size can-not be reliably measured. The maximum fillet weld sizeprovision protects the edge to enable the monitoring andinspection of the fillet weld leg and throat.

C-2.8.1.3 Fillet welds in holes or slots are consideredthe same as fillet welds along edges of surfaces. Filletwelded attachments may overlap, in the sense that theyare on opposite sides of a given hole or slot. Fillet weldsare not intended to intersect or pile-up on each other. Theeffective size of two fillet welds that overlap within ahole or slot is not necessarily the sum of the two throats,because it is limited to the plan area of the hole or slot.

C-2.8.1.4 Care is to be taken when welding skewedtee joints to ensure that the required weld size isobtained. Detail drawings, to scale, showing the requiredleg size and throat, are helpful to the welder and inspec-tor in providing the required weld size.

C-2.8.1.7 Boxing. Boxing requirements are applica-ble to lap joints when fillet welds are used to supportloads that produce a tension component transverse to thethroat of the fillet weld. Applied out-of-plane tensileforce has the effect of trying to pry the weld off the basemetal, tearing from the end of the weld, initiating at theweld root. By boxing, the ends of the longitudinal weldare restrained from opening, protecting the weld fromprying behavior. The concentration of stress at the endsof the fillet weld, where weld quality is generally poor-est, is also reduced by carrying the weld around the cor-ner of the joint. Because it restricts the flexibility of theconnection, boxing may need to be limited where con-nection flexibility is assumed, such as double-angle con-nections welded to the supporting member.

C-2.8.1.8 Opposite Sides of Contact Plane. It is dif-ficult to maintain weld quality across the plane of contactbecause it requires a welding position change and fre-quently creates notch defects and undercut where theweld crosses the part. A typical application for this situa-tion is the attachment of a cover plate that is wider thanthe flange as shown in Figure 2.6, or intersecting cross-frame members.

C-2.9.1 Details

C-2.9.1.1 The techniques of welding plug and slotwelds are substantially different than the techniques thatwould be used to weld WPS qualification test plates.However, plug and slot welds are not typically used forimportant welds to carry high stresses, and therefore pro-cedure qualification requirements are normally waived.

C-2.9.2 The minimum diameter limitation providesaccess to make good quality welds with adequate fusion.The maximum diameter maintains a reasonable size ofhole that may otherwise substantially reduce the net sec-tion of the part being joined.

C-2.9.7 This subclause contains a number of provisionsfor making plug and slot welds. Plug and slot welds havea high incidence of weld discontinuities when made bythe methods described in 4.21 and 4.22. For this reason,4.23 was added to the code, but does not guarantee thatsound plug and slot welds will be produced. Plug andslot welding are prohibited on tension and reversal mem-bers [see 2.14(6)]. Plug and slot welding should beavoided whenever possible. High strength bolts can alsobe used to transmit shear and to keep adjacent plies ofcompression members from separating or buckling.

Designs that require parallel plies of material to be joinedtogether by plug or slot welding are seldom used in mod-ern bridge construction due to inefficient use of weldmetal, the high incidence of weld discontinuities, and thesusceptibility to crack initiation and propagation.

C-2.10.1 Minimum Lap. A minimum lap of five timesthe thickness of the thinner part of the joint is necessaryto avoid unacceptable rotation of the joint. The eccentricforce tends to cause the plates to bend between thewelds. As the lap becomes longer, the bending tendencyis reduced. Lap joints with a single transverse fillet weldtend to open and apply a tearing action at the root of theweld. These joints are rarely used in bridge construction.

C-2.10.2 Longitudinal Fillet Welds. For longitudinalfillet welds used alone in a lap joint, the code requires,because of shear lag, that the length of each weld be atleast equal to the width between the lines of weld. Whenthe distance between the longitudinal lines of fillet weldsbecomes large, and buckling or separation of the partsbecomes possible, then plug welds, slot welds, or some


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other means are used to prevent separation or buckling.Because of the difficulty of achieving adequate weldquality in plug and slot welds, plug and slot welds shouldbe avoided when connecting cover plates or when mak-ing welded lap splices. When lap splices in tension mem-bers are required, the best method of connection isgenerally with high strength bolts (see 2.10.4).

C-2.11.1 Weld Arrangement. When applied loads maybend a corner or T-joint about its longitudinal axis, theweld is either a complete joint penetration (CJP) weld ordouble-sided fillet or double-sided partial joint penetra-tion (PJP) groove welds on each side of the joint so thattensile stresses will not be concentrated at an unwelded,root portion of the joint. All corner and T-joints, wheregeometry allows, are required to have reinforcing filletsto improve the flow of stress and to mitigate the unavoid-able stress concentrations present. When applied loadsperpendicular to the weld axis tend to induce compres-sive stress on the weld root, and corrosion and strengthconsiderations are satisfied, it may not be necessary toweld both sides.

C-2.11.2 Longitudinally Stressed Welds. Fillet weldsprovide the least expensive weld detail when applied shearstresses require fillet throat of about 18 mm [11/16 in] orless. Very large fillet welds should be avoided becausethey require excessive weld metal. As a general ruleof thumb, when the required fillet weld size approaches25 mm [1 in], the use of PJP groove welds with reinforc-ing fillets should be considered. Because of the methodof calculating effective weld size (throat), PJP groovewelds provide higher allowable shear capacity per poundof weld metal.

CJP groove welds are required only when shear or com-pressive stresses are unusually high, or when there is anapplied tensile stress transverse to the effective weldthroat. The provisions of this subclause allow bridgedesigners to use fillet welds and PJP groove welds whenfeasible and economical. Specifying CJP groove weldswhere not essential may increase cost, member distortionand residual stresses, and can lead to excessive amountsof repair welding.

C-2.12.1 Dimensional Tolerances. When the standardjoints of Figure 2.4 are being detailed, they may beadjusted using the “As Detailed Tolerances” provided inFigure 2.4. When being assembled (fit-up) for welding,the joint may vary from the details shown on theapproved shop drawings within the limits of the “As Fit-Up Tolerances” provided in Figure 2.4 for standardjoints, or 3.3.4 and Figure 3.2 for other groove weldedjoints. The fit-up provisions of Figure 2.4 are derivedfrom 3.3.4.

J- or U-grooves may be prepared before or after assem-bly, or after welding of the first side of a two-sided weld.Second side joint preparation made by gouging or grind-ing the root after welding the first side removesdiscontinuities in the root of the first weld and helps toensure weld soundness. All CJP groove welds madewithout steel backing, except the B-L1-S standard detail,are backgouged to sound weld metal and ground toremove gouging residue (carbon, copper, slag) beforewelding the second side. The backgouging may be usedto produce the second side joint preparation. Joint prepa-ration by gouging and/or grinding after the joint isassembled, but prior to welding, also helps ensure theaccuracy of the joint alignment.

For thicker materials, the most economic CJP grooveweld joint preparations are often J- and U-groove prepa-rations, based upon lower weld volume. These joints pro-vide the best access for welding at the root and use theleast amount of weld metal. However, J- and U-groovepreparations are rarely used in shops prior to assemblybecause of assumed high costs since, prior to assembly,these joints can only be produced by machining. Thesedifficulties may be overcome by modifying the thermalcut preparation of the top of the joint during initial prepa-ration, then completing the joint preparation after assem-bly by air carbon arc gouging to produce the requiredroot radius. Automatic machines are available that pro-duce high quality joint preparations at reasonable cost.

C-2.12.2 Corner Joints (see Figure C-2.1). When oneonly considers access for fusion between weld metal andbase metal, which plate is beveled during preparation ofthe weld joint is not significant. However, since lamellartearing is potentially a serious problem in corner and T-joints where shrinkage stresses pull upon the base metalin the short transverse or “Z” direction, efforts should bemade to minimize the potential for tearing. Shrinkagestresses have less adverse effects on plates stressed in thelongitudinal direction (parallel to the rolling direction).There is little adverse effect when plates are stressed trans-verse to the rolling direction. However, stresses in theshort-transverse, or “Z” direction, especially when theplate has nonmetallic inclusions, may cause lamellar tear-ing. Corner joints are particularly susceptible becauseone plate is stressed at its end or edge where the is nopossibility to redistribute the stress, therefore the bevelshould be made on the plate that will be subjected to the“Z” stress. This procedure spreads the shrinkage stressesfrom the surface toward the center of the plate or shape,and reduces the potential for tearing. Controlling weldvolume, limiting weld metal yield stress, increasing pre-heats, using PWHT, and the use of controlled sulfurinclusion steels reduces the risk of lamellar tearing. Notall methods are needed for every application.


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Plates may be ordered with improved through-thicknessproperties. They are produced with reduced sulfur con-tent and controlled sulfur morphology, such that the sul-fur that remains is not flattened by rolling to produceplanar discontinuities parallel to the rolled surface. Suchplates are available at increased material cost, and speci-fied in the contract documents if required.

C-2.13 PJP Groove WeldsPJP groove welds are prohibited in any applicationwhere tensile stress may be imposed by live or deadloads normal to the weld throat. There is no code restric-tion on the use of PJP groove welds oriented parallel tothe applied stress (see C-2.5).

PJP groove welds may be used to carry shear stresses inbridge members regardless of the type (tension or com-pression) or intensity of the stress in the member. Theeffective groove weld size is to be sufficient to carry theapplied stress without exceeding design allowablestresses. Longitudinal PJP welds in corner and T-jointsmay be used to join web to flange in I-shaped and box-shaped members.

C-2.13.2 Minimum Effective Weld Size. The minimumweld size is based upon the need for adequate heat inputto slow cooling rates, and to provide a lower bound levelof strength to assure that handling stresses during fabri-cation can be accommodated.

C-2.13.3 Corner Joints. See 2.12.2.

C-Figures 2.4 and 2.5

CJP Groove WeldsC-Figure 2.4

B-L1a, C-L1a, B-L1a-GF. These joint details are onlysuitable for groove welds in thin material. Because oflimited access at the root and the possibility of fusiondiscontinuities at the root, caution should be used forwelds carrying calculated stress.

B-L1b, B-L1b-GF, B-L1-S, B-L1a-S. When a squaregroove is made without steel backing, lack of fusion atthe root pass is common. Note 3 requires welds madewithout steel backing to be backgouged to sound metal toremove fusion discontinuities in the root of the first sideweld before welding the second side. When using SAW

with material 10 mm [3/8 in] or under in thickness, anexception to this backgouging requirement is made. Thisdetail has been commonly used for bridge girder websplices.

TC-L1b, TC-L1-GF, TC-L1-S. This group of joints issimilar to the above group beginning with B-L1b. Back-gouging is required for all joints, including the SAWjoint limited to 10 mm [3/8 in] in thickness.

B-U2, B-U2-GF, B-L2c-S. Because of the wide grooveangle, these joint details use excessive weld metal inthick sections and increase angular distortion. Backgoug-ing is required on the second side.

Whenever the second side weld is not larger than thefirst, there may be insufficient weld shrinkage to coun-teract the angular distortion produced by the first weld(see C-2.1.2).

B-U2a, B-U2a-GF, B-L2a-S, B-U2-S. These details aresuitable for all thicknesses. These are particularly usefulin avoiding out-of-position welding and are commonlyused for field welding and repair. As weld sizes increase,these joints become less and less economical. Root open-ings and groove angles should be adjusted to require theminimum weld volume. Large included angles increasedistortion in weld joints that join thick sections. TheB-L2a-S weld detail is limited to a maximum thicknessof 50 mm [2 in], because as thickness increases, theangular distortion may become excessive. Access for theSAW equipment is also limited when the thicknessexceeds 50 mm [2 in]. This is overcome by increasingthe root opening to 16 mm [5/8 in].

C-U2, C-U2-GF, C-U2b-S. Because of the wide grooveangle, these joint details use excessive weld metal inthick sections and increase angular distortion. Backgoug-ing is required on the second side.

C-U2a, C-U2a-GF, C-L2a-S, C-U2-S. These details aresuitable for all thicknesses. These are particularly usefulin avoiding out-of-position welding and are commonlyused for field welding and repair. As weld sizes increase,these joints become less and less economical. Root open-ings and groove angles should be adjusted to require theminimum weld volume. Large included angles increasedistortion in weld joints that join thick sections. The B-L2a-S weld detail is limited to a maximum thickness of50 mm [2 in], because as thickness increases, the angulardistortion may become excessive. Access for the SAWequipment is also limited when the thickness exceeds 50mm [2 in]. This is overcome by increasing the root open-ing to 16 mm [5/8 in].

B-U3b, B-U3-GF, B-U3c-S. As a two-sided weld, it maybe detailed to minimize angular distortion by makingadjustments to the location of the root face or minor


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adjustments to the groove angle. For thicker sections, theweld volume is still minimal compared to a single-sidedweld. It is best when assembled with a very small, orzero, root opening, with sufficient root face to supportthe welding heat of the root pass. When the root openingis the maximum allowed and/or the root face is small ornonexistent, making a sound weld without burningthrough is difficult. The root face should be adequate toabsorb the welding heat without burning through, sincethe weld will be backgouged.

B-U4a, B-U4a-GF. This joint is restricted to groove weld-ing in the horizontal position. It is commonly used forfield welding, particularly the joining of steel piles dur-ing driving. The joint is not used for other welding posi-tions because the access for welding is not as good as inother joints where both groove faces are beveled. There-fore the double bevel detail is required for the otherwelding positions. It had been common for details to pro-vide a lower section bevel up to 15°. This is no longerprovided for in this figure, but the application of bothdetail and assembly tolerances would allow this practice,if desired. Joint B-U5a still provides for beveling of thelower section.

TC-U4c, TC-U4c-GF, TC-U4a-S. Welds in T-jointsshould be made from one side with steel backing onlywhen a CJP groove weld is required and when there is noaccess to the backside of the weld for backgouging andbackwelding. Welds of this type use excessive weldmetal when compared to balanced two-sided welds.Angular distortion may become excessive when the partsare free to move, and high residual stresses may be cre-ated when the parts are not free to move.

CJP corner welds should be made by beveling the platethat will be stressed in the “Z” direction, as noted in thefigure on the right. This will help avoid lamellar tearing.

B-U4b, B-U4b-GF. This butt joint is restricted to weld-ing in the horizontal position because of weld access,similar to B-U4a. Backgouged welds require less weldmetal than similar welds made against backing. Weldquality is generally superior when backgouging isrequired because root pass discontinuities are removed.Note that the root face is not limited during fit-up. How-ever, it is essential that there be sufficient root face toprevent burning through. Any remaining root face isremoved by backgouging.

TC-U4b, TC-U4b-GF, TC-U4b-S. Welds in T-jointsshould be made from one side with steel backing onlywhen a CJP groove weld is required and when there is noaccess to the backside of the weld for backgouging andbackwelding. This detail is used when access is availablefrom the backside for backgouging and backwelding.Angular distortion may become excessive when the parts

are free to move, and high residual stresses may be cre-ated when the parts are not free to move.

Backgouged welds require less weld metal than similarwelds made against backing. Weld quality is generallysuperior when backgouging is required because rootpass discontinuities are removed. Note that the root faceis not limited during fit-up. However, it is essential thatthere be sufficient root face to prevent burning through.Any excess root face is removed by backgouging.

CJP corner welds should be made by beveling the platethat will be stressed in the “Z” direction, as noted in thefigure on the right. This will help avoid lamellar tearing.

B-U5a, B-U5-GF. This type of joint preparation is moreeconomical in the use of weld metal than joints requiringsteel backing. Note that the lower plate may be beveledup to 15°. Like all other bevel or J-groove welds, thisjoint preparation is only allowed to be used in the hori-zontal position. The included angle is only 45°, eventhough the root opening may be zero. Other weld detailswith similar access require 60°. Backgouging to soundmetal before welding the second side helps ensure weldsoundness and makes large included angles for rootaccess unnecessary.

TC-U5b, TC-U5-GF, TC-U5-S. This is similar to the B-U5 joint detail above. The 60° included angle for SAW isto limit the shape of the weld nugget and prevent centerbead cracking (see Figure 4.1). SAW does not need moreaccess than other processes.

B-U6, C-U6, B-U7, B-U8, TC-U8, B-U9, TC-U9 andVariations. All of these joints use J- and U-grooves.These joints provide the best access for welding and usethe least amount of weld metal when thick sections are tobe welded. Angular distortion is minimized because ofthe narrow groove angles required, particularly the 20°grooves. Such narrow groove angles may be utilizedbecause of the rounded, wide root that offers goodaccess. In practice, they are rarely used except in thickjoints because of the cost of preparing the J- or U-groove. These joints with rounded roots provide aneffective root opening of 12 mm [1/2 in] in U-groovesand 10 mm [3/8 in] in J-grooves because of the specifiedroot radius.

These CJP groove welds are backgouged before weldingthe second side, resulting in a J- or U-groove at the root.V or single bevel groove preparation is generally done bythermal cutting, which is less expensive machining orgrinding. Bevel or vee joints modified to produce arounded root may justify the time and expense of qualifi-cation testing if sound welds are produced at significantlyreduced cost.


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The root face specified for these joints is expected to pre-vent melting through. A generous root face can be help-ful to prevent burning through and is no detriment toweld soundness since the weld is required to be back-gouged to sound weld metal before welding the secondside. In most cases the code states that the fit-up toler-ance on root face dimension is unlimited. Melting throughat the root and loss of support for the arc may causeserious discontinuities needing repair before welding cancontinue.

PJP Groove WeldsC-Figure 2.5

Most commentary on the CJP details of welded joints,including access for welding, economy, distortion, sus-ceptibility to lamellar tearing, etc., also applies to PJPgroove weld details. The primary difference between PJPand CJP groove welds is that an unfused area exists at theroot of the PJP groove weld or welds. There is no back-gouging. The amount of lack of fusion at the root of thejoint preparation will depend upon the root opening, thegroove angle, and the presence or absence of a rootradius. The design and preparation of shop drawingsshould take into account the difference between thedepth of the groove preparation and the effective weldsize.

C-Notes for Figures 2.4 and 2.5

Note a. Each WPS has slightly different requirements foraccess during welding. In SMAW, the electrode diametercontrols. In FCAW-G and GMAW, the diameter of thegas cup controls. The position of welding also has someeffect on access requirements. GMAW and FCAW arecapable of deeper penetration, depending upon weldingvariables and shielding gas, if any.

SAW is somewhat different because it is capable of muchdeeper penetration than most other processes, particularlywhen operated electrode positive. SAW is also differentfrom the other procedures because it is not an open arcprocess, in that the SAW arc is not seen during welding.Electrode placement cannot be controlled by visual moni-toring as is done in other arc welding processes.

These considerations become very important in largenonstandard joints but are not a factor in the detailsshown in Figures 2.4 and 2.5.

Note g. A double-groove weld joint that places morethan 75% of the weld throat on one side of the joint hashigher residual stresses and distortion from shrinkage ofthe greater weld volume and weld width.

Double-groove welds that have each side welded com-pletely, without alternating sides, may use uneven groovedepths to balance distortion. Generally, the first sidewelded should have approximately one-third of the totalgroove depth, and the second side welded should haveapproximately two-thirds the total groove depth. Thesmaller first side weld is unrestrained from shrinkage andangular distortion, whereas the second weld is restrainedby the first weld, and therefore needs additional weldvolume to return the joint to approximately its originalposition.

C-2.14 Prohibited Types of Joints and Welds

This subclause prohibits welded joint details and weldingconditions that may leave an unwelded area or poor qual-ity weld in a portion of the joint, resulting in stress con-centrations that may initiate fatigue cracking.

(1) Groove welds in butt joints not fully weldedthroughout their cross section are prohibited, unless usedin compression members with milled splices per 2.17.3.When tensile stress is applied normal to the unweldedportion of the joint, fatigue cracking may initiate.

(2) These joints are prohibited because withoutproper backing materials, it is more difficult to ensurecomplete fusion of the weld at the root, resulting in ahigh potential for reduced fatigue performance. Double-sided joints with backgouging, are allowed. It is also per-missible to qualify the use of backing materials otherthan steel, providing the tests described in 5.13 areconducted.

(3) Permanent intermittent groove welds are prohib-ited because they concentrate residual and applied stressat the ends of the welds, and the concentration of stressesmay initiate fatigue cracking.

(4) Permanent intermittent fillet welds are notallowed because they concentrate stress at the ends of thewelds, and the concentration of stresses may initiatefatigue cracking. Each intermittent weld is similar to aCategory E fatigue detail.

This restriction does not prohibit the use of intermittentfillet welds as tack welds to be welded over to complete acontinuous weld.


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The Engineer may allow the use of permanent intermit-tent fillet welds in specific applications such as the weld-ing of members exposed only to very low design cyclicstresses, few cycles, or to ancillary items listed in 1.3.6.Corrosion, distortion, and secondary stresses should alsobe considered.

(5) Previous editions of this code restricted certaingroove welds made with preparation on only one mem-ber to the horizontal position. Such groove types includebevel and J-preparations, as opposed to preparationswhere both members receive the treatment, such as V-and U-grooves. This restriction was placed because ofthe general preference for avoiding welding against avertical face whenever possible, and led to utilizing pre-ferred V- and U-groove details in lieu of bevel and J-groove details when either option was possible, since inthe flat, vertical, and overhead positions, it is generallyconsidered easier to make a quality weld when bothmembers are prepared to receive the weld metal. Whenwelding in the horizontal position, the single memberpreparations are preferred, and thus allowed by previouscodes.

This provision was changed because there are certainapplications where flat position welding with singlemember preparations is preferred. The most notableexample is for horizontal plates welded to flanges wherethe attachment functions as a transverse connectionplate. Under the previous editions of the code, thesewelds either needed to be made with two member prepa-rations (V- or U-groove details), requiring beveling ofthe main member (girder flange) for the length of theattachment; or, these welds were required to be made inthe horizontal position. Horizontal groove welding isgenerally more difficult than flat position groove weld-ing, and significant material handling is often required inorder to accomplish this task. In many cases, the specificrequirements of the code with respect to this applicationwere overlooked and the joint, with one member pre-pared, was actually welded in the flat position.

To overcome this problem, the 2002 code provision wasmodified by changing 2.14, as well as Note M in thenotes for Figures 2.4 and 2.5, allowing the use of thesedetails in the flat position, but disallowing such welddetails where V-groove and U-groove details are “practi-cable.” This term incorporates two concepts: 1) possibleor doable and 2) practical or generally accepted practice.

For example, routine web and flange butt joints made inthe flat position are quite readily accomplished with V-groove or U-groove details, and this is routinely done,that is, it is practicable. However, welding a horizontalconnection plate to a girder flange with a V- or U-groove

preparation is possible, but does not pass the practicaltest, and thus would not be practicable.

Contained within the term “practicable” is an element ofjudgment, deliberately incorporated by the Bridge Weld-ing Committee to allow appropriate latitude to addressthe myriad of situations that could arise.

(6) Plug and slot welds are not allowed on memberssubject to tension and reversal of stress because of stressconcentrations at the weld boundary. Plug and slot weldshave a high incidence of fusion defects that act as stressconcentrations, possibly causing crack initiation. Boththe weld metal and the surrounding base metal have lowallowable stress ranges for these reasons.

C-2.15 Combinations of WeldsThe capacities of individual weld types can be added todetermine the total capacity of a weld joint, with the sumnot to exceed the strength of the weakest member beingjoined. Fillet welds that reinforce CJP groove welds aregiven no credit in design. They simply help to improvethe flow of stress and minimize stress concentrations.The strength of fillet welds used to reinforce PJP groovewelds may be taken into account when calculating thestrength of a welded joint, provided the combined weldstrength does not exceed the capacity of the connectedmaterial (see Annex A).

C-2.16 Welds in Combination with Rivets and Bolts

Bolts and rivets have traditionally been prohibited fromsharing stress with welds in bridge design because mostriveted and bolted joints do not fully share the load andmay slip and cause the full load to be transferred to theweld. If joint slip happens only once and in one direction,it is possible that the weld could yield and then share theload with fasteners in bearing, as necessary. However,under conditions of stress reversal, once bolted or rivetedjoints slip, the “slip critical” bolted connection is lost.The AASHTO Design Specifications (Table 10.3.1B) doallow bolted cover plate terminations to improve thewelded cover plate’s fatigue category. Such a detail isnot considered load-sharing.

Unless required for strength, if bolts are removed afterassembly, it is generally preferred that the exposed boltholes should not be filled by welding. There is a consid-erable risk that discontinuities in the weld will lead to


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fatigue crack initiation (see 3.7.7 for welding techniquesand limitations for filling bolt holes).

C-2.17.1.1 General. Eccentricity of members shouldbe minimized whenever possible. When eccentricity isnecessary due to the configuration in the design ofmembers and connections, provision for the additionalstresses created by the eccentricity is necessary. Weldsshould be arranged, or diaphragms and other bracingmembers placed, so that tensile stresses are not concen-trated at ends of welds or at unwelded portions of weldedjoints.

C-2.17.1.3 Symmetry. Symmetric welds for symmet-ric members are desirable but may not always be possi-ble where connections or other attachments are made tothe primary member. Under such situations, allowance isneeded for the resulting eccentricity.

C-2.17.2 Connections or Splices—Tension and Com-pression Members. Connections or splices in bridgemembers that will transmit tensile and compressivestresses are required to be made using CJP groove weldsor fillet welds with external splice plates. CJP groovewelds in butt joints have the best fatigue strength becausethere is no unwelded portion of the joint to cause stressconcentration.

C-2.17.3 Connection or Splices in Compression Mem-bers with Milled Joints. Milled surfaces rarely mateperfectly. Per 3.3.2.2, the contract documents may spec-ify the tolerances for noncontact surfaces. When a mill-to-bear condition is specified for a column base plate oragainst a bearing assembly, welds accommodate local-ized plastic strains if these noncontact surfaces closeunder subsequent loadings. AISC and AREMA alsospecify fit-up tolerances for such joints that may beadopted for some situations.

This subclause does not apply to milled ends of bearingstiffeners or components within a bearing assembly.

C-2.17.4 Connections of Components of Built-UpMembers. A large portion of welding in bridge con-struction consists of longitudinal welds used to joinmember components, such as webs and flanges, to makethem act in unison. The applied stress on the welds isshear on the effective weld throat, even though the mem-ber may be axially loaded or subject to bending. Gener-ally, minimum weld sizes govern such connections.Intermittent welds are not allowed because of their poorfatigue performance.

C-2.17.5 Transition of Thicknesses or Widths at ButtJoints. When there is a transition in thickness or width,there is a concentration of stresses. Extensive fatiguetesting and the service history of thousands of weldedbridges has shown that transitions in weld and base metal

surfaces that provide a smooth transition of the surfacesor edges, or both, at a slope that does not exceed 1 on 2.5,ensures acceptable fatigue performance.

C-2.17.5.3 An abrupt change in width between ten-sion members causes a stress concentration at the pointof transitions. A gradual transition reduces this stressconcentration. Either a tapered transition or a radiusedtransition accomplishes this reduction in stress concen-tration. For lower strength steels, a 1:2.5 width:lengthtaper reduces the stress concentration to a level such thatthe allowable stress range is the same as a butt splice ofequal width. For higher strength steels the radiused tran-sition provides a slightly better performance than doesthe tapered transition. Accordingly, AASHTO designspecifications allow a slightly higher allowable stressrange for radiused transition versus tapered transition inthese higher strength steels. The slightly higher allow-able stress range rarely changes the bridge design, and itmay be easier for the fabricator to supply the taperedtransition. Thus, either transition detail is allowed,regardless of the strength level, but in all cases, theAASHTO allowable stress levels are not to be exceeded.

C-2.17.6.2 Splice Planes. Full cross-sectional splicesin beams and girders are generally best made in a singleplane. There is no strength or fatigue advantage to stag-gering the splice, and staggered splices are considerablymore difficult and expensive. Locations may be basedupon requirements for changes in material thickness, oras necessary to accommodate lengths of steel availablefrom the mill. Unnecessary flange and web splicingshould be avoided.

Before the webs and flanges are assembled to form abeam or girder, components of the web or flange arejoined by shop welding and the quality of the weldsaccepted (see 3.4.6). This provides the best access forwelding, and keeps residual stresses to a minimum byreducing restraint. When assembly and welding are donein this manner, the longitudinal web-to-flange welds canbe made by automatic welding procedures without inter-ruption. Field splicing built-up sections requires accessholes cut in the web. When flanges are spliced withoutbacking, the access or cope hole in the web may need tobe larger than one with backing. The hole providesaccess for welding, backgouging, and subsequent grind-ing of weld surfaces. Top or bottom access holes willalso be subjected to applied tension and/or reversal ofstress. Any notch in the weld or base metal at this loca-tion may initiate fatigue cracking. Thermal cut accessholes may have a thin layer of untempered martensitethat should be removed by grinding.

Many prefer to leave access holes open and have hadgood results in redundant members. A bridge member


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with an open access hole should have an allowabledesign stress range considerably lower than that allowedfor Category B. Flange to web fillet welds terminating ataccess holes are essentially Category E or E' details. Fill-ing of access holes requires skillful use of Engineer-approved procedures and should only be employed whenholes cannot remain open. Installing an insert platejoined to the web and flange using CJP groove welds isvery difficult due to access for backgouging, and weld

defects at corners may be more detrimental than anopen hole. The welds and base metal are at yield stresswhen the repair is complete, and there may be very highsurface or internal stress concentrations at the comple-tion of access hole filling. It is essential that the specifiedquality of access hole welding be verified by NDT.Welds in tension areas should meet the tension qualityrequirements of the code, and welds in compression areasshould meet the compression requirements of the code.


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Figure C-2.1—Details of Alternative Groove Preparationsfor Corner Joints (see 2.12.2 and 2.13.3)


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C-3.1.1 This introductory provision emphasizes the impor-tance of conformance with all workmanship requirements.When contract documents specify that construction is toconform with the requirements of the Bridge WeldingCode, it means all applicable provisions, not just Clause 3Workmanship.

C-3.1.2 The equipment should be proper for the job andin proper working order so that qualified people can doacceptable work. It is essential that gauges and controlson welding equipment function properly so that theWPSs established can be duplicated accurately. Equip-ment calibration is required on a regular basis (see 4.26).Personnel other than qualified welding personnel areallowed to use thermal cutting equipment.

C-3.1.3 Welding is not to be done under conditions thatmay lead to poor weld quality.

Ambient conditions are the conditions that prevail in theimmediate area where welds are to be made. It isassumed that welding personnel cannot consistently pro-duce acceptable results when working in an environmentwhere the temperature is lower than –20°C [0°F]. Shouldthe Contractor build a shelter to protect the welding area,the “ambient conditions” are within the shelter near theweld. If the structure or shelter provides an environmentat –20°C [0°F] or above, adequate light and protectionfrom wind, this prohibition is not applicable. The envi-ronmental conditions inside the structure or shelter donot alter the preheat or interpass temperature require-ments for base metals described elsewhere in the code.Conditions outside the shelter are of no consequence whendetermining whether or not welding may be performed.Low temperatures may also make it difficult formachines to function properly.

Any source of moisture such as condensation, dew, rain,or snow is a source of hydrogen during welding and is tobe eliminated. Moisture increases the risk of hydrogen-induced cracking and other weld discontinuities.

High winds blow away shielding gases, leaving anexposed arc free to pick up atmospheric gases. This con-tributes to porosity as well as higher nitrogen levels thatreduce weld toughness. Although high wind velocity isnot defined in the code for SMAW, FCAW-S, SAW, andESW, it is generally considered to be the wind speedwhich visibly blows the puddle, which typically occursaround 40 km/hr [25 miles/hr]. High winds also make itdifficult for welders to do their work properly. The gasshielded arc welding processes, GMAW, FCAW-G, andEGW, require more protection from the wind than theother welding processes, and are subjected to a wind speedlimitation of 8 km/hr [5 miles/hr] (see 4.14.3).

C-3.1.4 The approved shop drawings show welds of spe-cific size and length. This is done to provide the requiredstrength. Completed welds should be at least as large asshown on the drawings, unless otherwise approved bythe Engineer. Fillet welds may have a slight underrun insize as provided in 6.26.1.7. This later provision isintended to provide a reasonable tolerance on workman-ship and to avoid unnecessary repair by welding, whichcould cause more harm than good. Small localizedunderruns in size will not significantly impair strength orhave a significantly faster cooling rate. Small, largelycosmetic weld repairs may cause additional residualstresses, unacceptable hardening, inclusions, or otherdetrimental effects. Therefore, undersized welds may bebetter left unrepaired than repaired with small welds tobuild out the weld to full size.

Either or both legs of fillet welds may be oversized with-out correction, provided the excess does not interferewith satisfactory end use of a member. Attempts toremove excess material from oversized welds, with oth-erwise acceptable profile, serve no purpose. Adequacy ofthroat dimension and conformance to the weld profilerequirements of 3.6 should be the only acceptance criteria.

The location of welds is important for many reasonsincluding strength and fatigue performance. Weldsshould not be moved or rearranged from the design loca-

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tion shown on the plans and detailed on the shop draw-ings without the approval of the Engineer.

C-3.1.5 Temporary and unauthorized welds are a poten-tial initiation point for hydrogen and fatigue cracks.Welding is only acceptable where shown on theapproved drawings, and in conformance with coderequirements.

Repair welds to base metal under the terms of AASHTOM160M [ASTM A 6M] is allowed. However, it may bedifficult to verify that the repair by welding of plates andshapes at the mill has been performed under conditionsthat conform to code requirements. For fracture criticalmembers as provided in Clause 12, only the fabricatormay perform welded repairs to the base metal.

C-3.2.1 Poor quality of metal surfaces or edges canadversely affect the quality of welds made against thosesurfaces or edges. When metal was primarily cut byshearing, edges were often ragged and sometimes torn orcracked. Laminations in sheared edges sometimescaused the metal to split apart. By code, most metal isnow prepared for welding by thermal cutting. Thermalcut edges are generally superior to sheared edges, butstill need to be inspected carefully to ensure that theyconform to the requirements of this subclause.

Embedded and surface base metal discontinuities mayaffect performance of welded bridge members in afatigue environment. A good weld made over a notch orcrack may subsequently fail as a result. Welds may crackshortly after cool-down because stresses are concentratedby the discontinuities in the base metal. Pre-existingdiscontinuities in the base metal may also propagate asfatigue cracks, ultimately causing failure of the completeweldment.

Surfaces to be welded should be free from any materialor condition that will interfere with proper fusion, con-taminate the weld or introduce hydrogen, or create ahealth hazard for the welders. The welding arc is gener-ally able to burn through mill scale and rust, but as thequality of the surface deteriorates from a clean, brightcondition, so does the quality of the welds. The morenonmetallic material and oxides that are melted from thebase metal surfaces and removed from the weld by thewelding slag, the greater the chance of slag inclusionsand fusion defects. Hydrogen that is present in the weld-ing atmosphere, regardless of source, is absorbed by theweld and HAZ. When stress and hydrogen are combined,cracking may result.

Acceptable welds may be made through a thin coating oftight mill scale and the other light coatings that aredescribed in this subclause. Web-to-flange welds are fre-quently minimum size fillet welds deposited at relatively

high speeds, therefore these welds could exhibit pipingporosity if welded over the heavy mill scale often foundon thick flange plates. Therefore, flange-to-web welds ingirders have the mandatory requirement to completelyremove all mill scale. In stiffener-to-web welds, lightmill scale on the thin members forming the joints isacceptable.

C-3.2.2 The effect of thermal cutting on steel is complex.Thermal cutting is generally done by either oxygencutting or plasma cutting. Performance of steel bridgemembers constructed with plates or shapes with thermalcut edges may be affected by both the mechanical andmetallurgical properties of the cut surfaces that are sub-ject to tensile stress. Maximum surface roughness andfreedom from unrepaired notches are specified to avoidstress concentrations.

Both plasma and oxygen cutting can produce acceptablecut surfaces if the equipment is properly operated andguided. Free-hand cutting should not normally beallowed because it is difficult to achieve uniform, regularcut surfaces with this technique. However, free-hand cut-ting is sometimes necessary. The quality of the thermalcut surface is expected to conform to the requirements of3.2.2. When the Engineer approves free-hand cutting(without a mechanical guide), the cut surfaces still needto conform to the requirements of 3.2.2 and 3.2.4. Ther-mal cutting needs to be done with great care, avoidingany damage to the adjacent steel. Irregularities in the cutsurface may be corrected by grinding, or by welding fol-lowed by grinding as specified in 3.2.2.1, 3.2.2.2, and3.2.2.3.

A maximum surface roughness of 25 µm [1000 µin] isspecified for steel up to 100 mm [4 in] thick. 50 µm[2000 µin] is specified for thicknesses over 100 mm to200 mm [4 in to 8 in] inclusive, and for ends of membersnot subject to calculated stress. A 25 µm [1000 µin] sur-face roughness represents a 0.025 mm [0.001 in] devia-tion above or below a theoretical plane. Deviations ofthese dimensions generally do not cause significantstress concentrations unless extremely sharp. Inspectorsare not expected to measure surface roughness directly,so visual and tactile comparison with a surface roughnessgage is acceptable (refer to AWS C4.1, Surface RoughnessGuide for Oxygen Cutting).

The occasional notches and gouges in thermal cut edgesthat will not be a fusion face of a weld joint may berepaired by grinding, fairing-in the depression in theedge to adjacent surfaces on a 1:10 slope, provided therepair does not remove more than 2% of the nominalsection. Because there is less danger that new and moreserious discontinuities will be created, small repairs bygrinding are preferred to welded repairs. The number of


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repairs allowed in one region is not limited, but ifrepeated attempts to repair are required, the techniqueused for repair should be investigated.

C-3.2.2.1 Notches and gouges occur in oxygen andother thermal cut edges for two primary reasons: (1) thecutting unit is not guided or operated correctly, or (2) thesteel contains inclusions that interfere with cutting bydeflecting the cutting jet. When there are discontinuitiesin thermal cut edges solely as a result of the cutting pro-cedure, they may be repaired by welding as specified.When there are discontinuities in thermal cut edgesbecause the steel has inclusions, repairs cannot be madeuntil the extent of the inclusion and the possible effect ofthe inclusion has been determined. There is no limitationto the depth of gouge that may be repaired by weldingwhen the repair WPS is approved by the Engineer. Whenthe member will be subject to tension or reversal ofstress, repair weld quality is verified by test as requiredby 3.2.2.3. Compression member repair welding gener-ally requires only visual inspection because fatigue crackgrowth is limited in such members.

C-3.2.2.2 Because of their tendency to reach unaccept-able hardness with rapid cooling, welded repairs to notchesand gouges in thermal cut edges in 620 MPa to 690 MPa[90 ksi to 100 ksi] yield strength steels are limited to onlythose edges that will be included within a groove weldedjoint, or the faying surface element in a fillet welded teejoint. Welded repairs are prohibited for defects in por-tions of thermal cut edges other than these specific weldjoint types. For repair of unwelded portions and othertypes of welded joints, only grinding is allowed.

All repairs by welding for these steels are to be done withthe approval of the Engineer, and follow the require-ments of an approved WPS. Stringer bead techniquesshould be used for all weld repairs, except those made bywelding in the vertical position. Welding in the verticalposition, when approved, should consider the higherwelding heat input associated with that procedure. Totalheat input should not exceed the manufacturer’s recom-mendations. The soundness of repair welds is verified byNDT as described in 3.2.2.3.

The Engineer may approve repair by welding, regardlessof the depth of gouge, provided there is evidence that thesteel is sound and that the proposed repair WPS will pro-duce acceptable results.

C-3.2.2.3 Welded repairs to thermal cut edges inmembers subject to tension or reversal of stress are testedby both UT and MT because of the possibility thatfatigue cracks might initiate from weld discontinuities inthe repair. These two NDT methods were chosenbecause repair welds are generally expected to be shal-low, and because RT does not give good results near an

edge without the use of edge blocks. Visual inspection ofrepairs to compression members is satisfactory, unlessotherwise specified or required by the Engineer.

C-3.2.3 This provision addresses the significance ofvisually apparent discontinuities in cut edges. Theseedges are generally thermal cut edges, but may alsoinclude sheared, machined, and air carbon arc gougededges. Most indications in edges of base metal are paral-lel to the rolled surface. There may be several planes ofindications throughout the thickness of the material.These provisions are to keep repair welding to a mini-mum, consistent with good design and constructionprocedures.

A working knowledge of steelmaking aids the Engineerin understanding the origin of discontinuities found insteel products. Most indications are the result of non-metallic inclusions, such as manganese sulfides andsilicates, or are the remnants of voids left by escapinggases that are flattened out during rolling. Laminationsand inclusions are generally more prevalent in thickersections.

In ingot cast steels, there is a shrinkage cavity at the topof an ingot after solidification. The size of the cavity,called “pipe,” depends upon the method of casting andthe effectiveness of “killing” the steel. Killing is a degas-sing process through the addition of aluminum or silicon.The top of the ingot is to be “cropped,” cut off and dis-carded. When there is insufficient cropping at the top ofan ingot, major discontinuities may be found in the platesor shapes produced from that ingot. Plates ripped alongthe centerline are more likely to exhibit laminationsalong the edge. Many fabricators “nest” plates in oddquantities to ensure that “splitting” the plate along thecenterline is avoided.

Today, most structural steels are produced through a pro-cess known as continuous casting. The use of ingots iseliminated, as steel in the molten state is tapped directlyfrom ladles into casting units. The potential problem of“pipe” is eliminated. However, there is still the possibil-ity of small inclusions in the steel from fluxes and otherforeign elements within the steel, which is subsequentlycast and rolled out in the section. Weathering steels seemto have more nonmetallic inclusions than other structuralsteels.

Most of these indications have no bearing on the capacityof the steel to carry stress parallel or transverse to therolling direction, and do not adversely affect weldability.Inclusions and laminations can seriously impair thecapacity of steel to carry stress in the short transverse, orthrough-thickness “Z” direction.


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C-3.2.3.1 Discontinuities found in thermal cut edgesby visual inspection, or as a result of performing NDT,are investigated. Laminations may be discovered andmapped using longitudinal wave (straight beam) UT.Laminations are generally undetected by RT becausethey have no significant depth parallel to the inspectingradiation. The exception to this RT limitation is createdwhen adjacent welds cause gases to expand out of alamination, forming porosity that can be recorded byRT. However, what is detected is the porosity, not thelamination.

C-3.2.3.2 Table 3.1 summarizes the extent of investi-gation and repair needed, if any, based upon the length ofdiscontinuity in the cut edge and the depth of the discon-tinuity from the cut edge back into the steel. Thisincludes all edges of steel shapes and plates, regardlessof rolling direction and regardless of whether the edge isproduced by thermal cutting, shearing, machining or anyother process. When the depth of discontinuity exceeds3 mm [1/8 in] and grinding is not used to determine thefull depth, UT is used to determine the depth of disconti-nuity. UT using longitudinal waves (straight beam) isvery effective in detecting laminations.

C-3.2.3.3 Good base metal should not be removedunnecessarily. Shallow excavations made to discover thedepth of discontinuities may not require repair by weld-ing. Excessive metal removal reduces the net section ofthe plate or shape.

C-3.2.3.4 Unacceptable discontinuities that appear atthe surface of as-rolled material, such as the edges offlanges in beams, are not addressed by Table 3.1. Theyare repaired as specified in the delivery requirements orthe contract documents. The common specification fordelivery requirements of steels listed in this code isAASHTO M160M [M160] (ASTM A 6M [A 6]).

C-3.2.3.5 Inspection of cut edges should be doneearly so that there is no unnecessary delay to construc-tion. Edge discontinuities should be repaired andinspected before the material is incorporated into fabri-cated members. If a portion of the steel is found unac-ceptable and cannot be repaired, it needs to be replaced.In other cases, it may be desirable to put repaired platesin compression areas of the structure. This can often bedone by switching top and bottom flange plates withcommon dimensions or turning them end for end.

C-3.2.3.6 Repair of edge discontinuities by grindingand fairing-in is preferred to repair by welding. Weldedrepairs to Type Y defects are prohibited when the steel tobe repaired is 620 MPa or 690 MPa [90 ksi to 100 ksi]quenched and tempered steel. Other steels may berepaired by welding with the approval of the Engineer.Requirements include fairing-in on a 1 on 10 slope,

grinding parallel to the base metal surfaces, and avoidingnotches normal to the applied stress. If machining orgrinding is performed perpendicular to the applied stress,then surface roughness criteria is applied.

C-3.2.3.7 The provisions in this subclause apply spe-cifically to discontinuities longer than 25 mm [1 in] andextend back into the steel more than 25 mm [1 in].

(1) Discontinuities discovered in cut edges, or foundas a result of NDT, may have fairly large areas viewed inplan but rarely have much volume because they havenegligible thickness. ASTM A 435M [A 435] provides alongitudinal beam UT aimed at finding significant areasof complete loss of back reflection. Complete loss ofback reflection may signify separation of the steel in thethrough-thickness direction. The generous acceptance oflarge planar discontinuities parallel to the applied stress,as provided by this provision, is based upon the knowl-edge that this form of discontinuity generally does notimpair strength or fatigue life. History has not shownthese internal discontinuities to be a cause of failure.Occasionally, when laminations form the boundary of aweld joint, gases produced by welding heat may causevoids in the weld which, because of their size and orien-tation, may reduce fatigue life. No welding is allowedacross edges of laminations or seams normal to appliedstress because it concentrates stress and may causecracking (see C-3.2.1).

(2) Provided there is no weld discontinuity at thefusion line between the weld and the lamination, TypesW and X have little or no effect on performance. Multi-ple layers of low hydrogen SMAW, applied as thin lay-ers not exceeding 3 mm [1/8 in], may be used for sealingoff laminations from the primary weld. SMAW fillermetals historically have provided high toughness in theweld metal, and because of low penetration, the weldingarc produces little gas at the weld/base metal interface.

(3) If a Type Z discontinuity is surrounded by soundweld or base metal, it is acceptable unless located close toa weld. The high residual stresses created in the vicinityof the weld, the characteristics of the HAZ, and the sharpnotch effect of a lamination may cause the lamination toextend into the weld region as a crack. A Type Z lamina-tion does not appear at the groove face for detection priorto welding. However, its presence may be detected whenNDT is performed of the completed weld.

If the Type Z discontinuity is within 25 mm [1 in] of theweld groove face, the lamination is investigated. Goug-ing exposes the lamination, and repair using SMAWtechniques to seal off the lamination from the weldregion may be performed to keep the tip of the remaininglamination at least 25 mm [1 in] away from the weld.Multiple layers of low hydrogen SMAW, applied as thin


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layers not exceeding 3 mm [1/8 in], are used to seal lam-inations from the primary weld. At least four layers ofSMAW weld are used, then other processes may beselected for additional welding closer to the primaryweld. SMAW filler metals historically have providedhigh toughness in the weld metal, and because of lowpenetration, the welding arc produces little gas at theweld/base metal interface.

(4) The area of lamination allowed before replace-ment or repair is required is described in 3.2.3.7(2).Repairs to areas exceeding these limits may be per-formed only with the approval of the Engineer.

(5) The maximum length of welded lamination repairis 20% of the length of the base metal edge. This appliesto all cut edges, and therefore restricts the length of dis-continuities in transverse weld groove faces to 20% ofthe plate width maximum. The Engineer may approvethe use or repair of material that exceeds these limits.

If there is sufficient extra length, the defective end of thepart may be cut off. If the length is insufficient, thedefective end may be removed and a replacementattached by groove welding using a butt joint. Replace-ment plates and additional CJP groove welds requireapproval of the Engineer. The minimum flange replace-ment length should be at least 2.5 times the part width toavoid concentrations of residual stress in the base metalbetween welds.

(6) All Type W and X discontinuity repairs are madewith low-hydrogen electrodes. For Grade 690/690W[100/100W] steels, the maximum electrode diameter is4.0 mm [5/32 in]. For other grades of steel, the electrodediameter is not limited except by Clause 4. For Grade690/690W [100/100W] steels, the repair weld quality isinspected no less than 48 hours after completion, and thegroove weld is not made until the quality of the repairweld has been accepted by the Engineer. Grade 690/690W [100/100W] steels may experience delayed crack-ing (see 6.26.1.9).

SMAW repairs made using 3.2 mm [1/8 in] or 4.0 mm[5/32 in] low hydrogen electrodes produce excellenttoughness and are not likely to produce gases from basemetal discontinuities. 3.2 mm [1/8 in] electrodes willhave lower heat input. The use of higher heat inputs orhigher preheat and interpass temperatures should be con-sidered to prevent unacceptable hardening.

(7) Any approved WPS may be used. For Grade690/690W [100/100W] steels, the maximum electrodediameter is 4.0 mm [5/32 in] on Types W and Xdiscontinuities.

C-3.2.4 When the cut edge of a plate or shape changesdirection, the corner of the cut is to have a radius of not

less than 25 mm [1 in] between tangents, or 50 mm [2 in]diameter. The rounding of the corner is to reduce stressconcentration at the transition of the member, and tofacilitate a high quality cut. Reentrant corners made bythermal cutting need to be ground. Drilled holes may alsobe used to form the radius, then thermal cutting for thestraight portions of the cut. Notches in the corner are pro-hibited, and removed by grinding.

Most reentrant corners are cuts into the section and havean included angle of 90°. Reentrant cuts may be made toallow penetrations by intersecting members or utilities.Intersecting cuts need to be made in a manner thatwill not create notches that concentrate stress (see FigureC-3.1).

This provision does not address global stress concentra-tions and fatigue performance at reentrant corners fromin-plane or out-of-plane stresses or deformation.

C-3.2.5 Copes are frequently made to floor beam anddiaphragm flanges so that members can be connected tothe supporting member. Copes allow the elevation of thecoped member to come up as high or higher than the sup-porting member, avoiding interference with the flange ofthat member. Weld access holes are sometimes needed toprovide access at groove welds for welding and inspec-tion. Both copes and access holes form a reentrant corner,and the minimum radius requirements of 3.2.4 applies. Asmooth transition, with no sharp corners or notches, isrequired.

The creation of unnecessary stress concentrations shouldbe minimized. Web cuts necessary to form weld accessholes should transition gradually and smoothly into theplane of the flange (see Figure C-3.2). The stress concen-tration is due not only to the change in cross section, butalso to the interruption of the residual stress field of thecontinuous longitudinal web to flange welds.

C-3.2.6 Cutting of base metal may be performed usinga variety of processes, including oxygen cutting andplasma arc cutting. However, oxygen cutting and oxygengouging are not allowed to remove unacceptable weld orbase metal, nor are these processes allowed for back-gouging. Oxygen deflected by nonferrous or oxidizedmaterial in the cutting stream can cause damage tosurrounding sound weld and base metal. Air carbonarc and plasma arc gouging are allowed because metalremoval is accomplished using compressed air. Com-pressed air is 80% nitrogen and only removes metalmelted by the arc or plasma. Metal removal may beaccomplished by any procedure that will not damage theweld and base metal that is to remain.

Air carbon arc gouging should be done using direct cur-rent (DC) with the electrode positive, also called reverse


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polarity. When using electrode positive, the flow of elec-trons concentrates the heat of the arc in the steel and pre-serves the rounded shape of the gouging electrode tip.This produces smooth, clean, cuts and gouges when theelectrode is manipulated properly. Gouging using AC isalso allowed, but the results are less favorable. Gougingusing DC with the electrode negative causes the elec-trode to quickly form a very sharp point. Combined withless effective base metal melting under these conditions,proper gouging is difficult. Copper from the carbonelectrode’s sheath will also be deposited on the gougedsurface.

Failure to direct sufficient air volume and pressure to theelectrode tip during gouging, failure to turn on the airbefore striking the arc, and dipping of the electrode intomolten metal that is not removed because of insufficientair pressure at the arc, will contaminate the base metalsurface with carbon and may cause excessive hardeningand cracking. All air carbon arc gouging surfaces shouldbe ground to remove surface irregularities and carbonand copper pick-up from the electrode. When air carbonarc gouging is done properly, little grinding will be nec-essary to produce a smooth clean surface. All thermalcutting and gouging procedures create a HAZ that hasincreased hardness. The HAZ produced by air carbon arcand plasma arc gouging is normally so shallow that itshould be of little or no consequence, particularly on sur-faces that will be reheated by subsequent welds. How-ever, grinding to bright metal should be required for allair carbon arc gouging surfaces. Plasma arc gouged sur-faces normally do not require grinding, unless unaccept-able surface irregularities are present (see NCHRPReport 384 for research concerning plasma arc cutting ofbridge steels).

C-3.2.7 Camber in built-up members will normally beprovided by cutting the web member to approximate therequired finished camber. Weld shrinkage and residualstresses may cause members to change camber duringwelding. The amount of camber change in bending mem-bers will be affected by many things, including whetherthe tension or compression web-to-flange weld is madefirst. The greatest amount of camber change often occursduring the cutting of the web plate. Camber changes canoccur due to residual stresses induced by mill rollingoperations or thermal cutting of nested web plates. Cam-ber change will also depend upon how many stiffenersand connection plates are welded to the flanges, the rela-tive mass of the flanges, the nesting of web plates, andother details of welding that shorten areas of flexuralmembers. Extra camber may be cut into the webs of fab-ricated bending members to compensate for shrinkagelosses. At the fabricator’s option, members should alsohave extra length to compensate for axial shrinkage. If

the finished piece has excess camber after welding iscomplete, the member may be accepted without repair,depending upon how much excess camber exists. Limitedexcess camber is accepted by the code (see 3.5.1.3).

Heating methods may be employed to remove unaccept-able excess camber. Corrections to members with lessthan the specified camber require approval of the Engi-neer before corrections are made. Those with excesscamber may be corrected without prior Engineer’sapproval. Steels should not be heated above 650°C[1200°F] to avoid the possibility of undesirable transfor-mation products or grain coarsening, or both (see 3.7.3for limitations on the application of heat).

Heat cambering of members may not be permanent.Some camber is generally lost as yield point residualstresses dissipate. When heating is done to decrease cam-ber, and some returns due to relaxation of the residualstress applied by the heating, it generally is of little con-sequence because of the positive camber tolerance. How-ever, when heat cambering methods are used to correctinsufficient camber and the camber achieved is not per-manent, the result may be unsatisfactory. All fabricatedstructural members should be cambered by cutting suffi-cient design camber, plus shrinkage camber, into the pro-file of the web(s) before assembly and welding.

C-3.2.8 Quenched and tempered steels may be heat cam-bered and heat straightened. However, great care isneeded when attempting to heat camber or straighten anyquenched and tempered steel. The procedure needs to befully understood and controlled, and requires priorapproval of the Engineer. The effective heat camberingtemperatures are close to the transformation temperatureof the steel, and serious damage can be done to themechanical properties of the steel, particularly the steel’stoughness. Quenched and tempered steels are not to beheated above 600°C [1100°F].

C-3.2.10 Edge Trimming. Edges of material arerequired to be trimmed, if and as required, to produce asatisfactory welding edge. This subclause specifies thattrimming is necessary if the material is welded along itsedge, carries a calculated stress, and the thickness of thesteel exceeds the specified amount. Rolled edges ofshapes and plates are not intended to form the boundariesof groove welds without preparation, as they may con-tain surface discontinuities from the rolling and straight-ening operations. Any unsoundness such as seams, laps,or laminations in a sheared or rolled edge are to beremoved and repaired before welding. Within the limitsof groove welded joints, all rolled edges are to be fin-ished by thermal cutting, grinding, or machining, as nec-essary to produce sound welding surfaces of thedimensions required by the approved details of welded


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joints. Sheared edges may contain tearing or microcracksfrom the shearing operation, which may lead to welddefects or base metal defects in HAZ areas in thickermaterials.

The code addresses sheared edges, rolled toes and edges,and universal mill plate edges. Rolled plate edges do nothave any specific contour and are rolled with just a hori-zontal mill. Universal mill plates have been rolled usingboth horizontal and vertical mills and subsequently havea more uniform edge. Plate directly from standard hori-zontal mills may be sheared to the desired width, but ismore commonly sheared at the fabricating shop. Thickerrolled mill edges may be folded over and encapsulateheavy mill scale within the fold. They are unsuitable forwelding until the edges have been trimmed back to solidsteel by shearing or thermal cutting, and there is nolonger any trace of the original plate edge.

C-3.3 AssemblyThe quality of the assembly for welding affects the qual-ity of finished welds and the total cost of welding. Manyof the assembly tolerances described in this subclause arebased upon the difficulty of getting large, heavy, mem-bers to fit-up properly. All joints should be assembled forwelding using the minimum root opening that is consis-tent with the access needed to make sound welds. Whenlarge root openings are allowed by the code, particularlyin the case of fillet welds, it is in recognition that evensubstantial force cannot push or pull some heavy sectionsinto the desired position. Excess assembly forces maylead to cracking and lamellar tearing because of the highresidual stresses created.

C-3.3.1 For fillet welds, intentional separation betweenparts is typically unnecessary. There is generally ade-quate separation for shrinkage stresses from the inherentirregularities in edges and surfaces, even when partsappear smooth. The weld metal described by the code isable to sustain residual and applied stresses withoutcracking, even when the parts joined are in full contact.

When the gap between the connected parts exceeds2 mm [1/16 in], the corresponding fillet weld leg dimen-sion is increased by the amount of the root opening,regardless of the welding method or process used, inorder to achieve the required weld size. No reduction ineffective throat is taken when the gap between the partsis 2 mm [1/16 in] or less, and no increase in leg dimen-sion is required. When parts are difficult to bring intocontact, sound welds may be made with gaps of up to 5mm [3/16 in]. The fillet weld produced in that situation

may actually become combination groove-fillet weldbecause the arc penetrates the root. No design credit isgiven for penetration at the root, however, regardless ofroot opening. When heavy sections 75 mm [3 in] orgreater in thickness cannot be brought into close proxim-ity, a modified fillet weld may be made with a maximumgap of 8 mm [5/16 in] between the parts by using suitablebacking, but only the effective fillet size is considered tocarry the load.

The most common use of fillet welds is to join the web tothe flange in built-up longitudinal members. Filletwelded joints made with large root openings have anincreased risk of weld discontinuities. Good fit-up forwelding improves weld quality and significantly reducesthe amount of weld metal necessary to make the connec-tion. Less weld metal means smaller residual stress, lessdistortion, and reduced risk of lamellar tearing andcracks. This assumes that the welds are large enough tocarry the stress and result in cooling at acceptable rates.

C-3.3.1.1 Tight fitting backing improves weld qualityand the ability to make accurate NDT. Steel backing is tobe removed from groove welds in butt joints subject totension and reversal of stress (see 3.13.2 regarding steelbacking).

C-3.3.1.2 Filler plates have a long history of use inbridges constructed with riveted and bolted joints. Whenfiller plates are used to make fillet welded connections inmembers, as shown in Figures 2.1 and 2.2, and the jointis subject to tension and reversal of stress, the fatigue lifeof the member may be reduced. A filler plate is part of awelded connection and shown on the design drawings.

C-3.3.2 Parts to be joined by PJP groove welds regard-less of the direction of stress should be brought into asclose a contact as possible. As root openings increase,the chance that significant weld discontinuities will beformed in the root also increases. In longitudinal welds,porosity and slag in the root may form stress raisers thatare normal to the applied stress. Discontinuities, espe-cially with significant dimensions normal to appliedstress, may adversely affect fatigue life.

C-3.3.2.1 When parts are difficult to bring into con-tact, sound welds can be made with gaps of up to 5 mm[3/16 in]. When heavy sections 75 mm [3 in] or greaterin thickness cannot be brought into close proximity,suitable backing is needed. The maximum gap using thismethod is 8 mm [5/16 in].

Large root openings in PJP groove welded joints increasethe likelihood of creating weld discontinuities. Good fit-up for welding improves weld quality and significantlyreduces the amount of weld metal necessary to make theconnection. Less weld metal causes smaller residual


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stress, less distortion, and reduced risk of cracking. Thisassumes that the welds are large enough to carry thestress and to produce cooling at acceptable rates.

C-3.3.2.2 The design of bearing joint welds assumesthe load to be shared by direct bearing of the steel partsupon each other and by the welds. In such cases, the partsneed to be in intimate contact and have no separationbetween bearing surfaces greater than the amount speci-fied in the contract, generally limited to a maximum of1 mm to 1.5 mm [0.040 in to 0.060 in]. For bearing stiff-eners, see 3.5.1.9.

C-3.3.3 Parts to be joined by groove welded butt jointsare aligned so the full thickness of the thinner element iseffectively joined, and stress created by eccentricity isminimized. Slight offsets are allowed because it is nearlyimpossible to align adjacent members perfectly. Theminor offsets allowed by the code are not significantstress raisers.

When it is impossible to line up butt joints between adja-cent members, particularly when the problem is causedby slightly different dimensions of adjacent pieces, itmay be best to separate web from flange as necessary toalign the abutting sections, then restore the web-to-flange connections using an appropriate repair weld.

C-3.3.4 The table in this subclause describes assemblytolerances similar to those described in Figures 2.4 and2.5 under the heading “As Fit-Up” for SMAW, FCAW,and GMAW joints. There are minor variations betweenthe tolerances provided in this subclause, as illustrated inFigure 3.2, and the tolerances for the joints in Figures 2.4and 2.5. For the joints in Figures 2.4 and 2.5, apply thetolerance as provided in the figures for the joints and pro-cess as selected.

The tolerances are selected (1) based upon good work-manship practices, (2) to ensure, through minimum rootopenings and groove angles, adequate access to makesound welds, (3) to reduce the risk of single-pass weldroot cracks from shrinkage stresses when the root open-ing is too wide, (4) to discourage the use of excessiveweld metal, and resultant shrinkage stresses and distor-tion, because of wider root openings and groove angles,(5) to provide adequate tolerance to the root face dimen-sion so that the root pass does not melt through the material,and (6) to ensure adequate weld size when backgougingis not performed. When joints are to be backgouged, thedimension of the root face is not critical, as long as thereis sufficient metal to absorb the welding heat withoutmelting-through.

Figure C-3.2 These details illustrate assembly tolerancesusing simple joint details, and are not intended to repre-sent recommended details of welded joints. Single V-

groove details create more angular distortion when partsare free to rotate. Balanced two-sided weld designs arerecommended when there is in-position access for weld-ing on both sides of the joint.

C-3.3.4.1 Because of material and assembly toler-ances, groove weld joints may not always fit as desired.When the root opening exceeds that allowed, root open-ing dimensions may be corrected by adding sound weldmetal to produce the intended root opening. Weldingacross the entire face of the groove may be necessary tomaintain the required groove angle. To help controlshrinkage stresses that are imposed on the adjacent basemetal or structure, corrections are made to the respectivegroove weld preparation surfaces before the design weldis made. All repair welding is to be done on the free endsof pieces, before joining the pieces together. To controlthe amount of shrinkage, and distortion, the code limitsthe correction to twice the thickness of the thinner part,or 20 mm [3/4 in], whichever is less (see 3.2.2.1).More extensive corrections require prior approval of theEngineer.

C-3.3.5 Groove weld preparations produced by air car-bon arc gouging are expected to be in substantial con-formance with the details for J- or U-groove weldsshown in Figures 2.4 and 2.5. This method of joint prep-aration, compared to machining, is expected to incurmore minor deviations, but these are generally not detri-mental to weld quality. Exactness of details regardingsize and radius are nearly impossible to achieve, there-fore reasonable tolerances should be applied. Othergroove weld details produced by gouging that are sub-stantially different than those shown in Figures 2.4 and2.5 are qualified by test and approved by the Engineerprior to use.

C-3.3.6 Proper assembly requires that the parts to bejoined be brought into their required position and helduntil the final welds have sufficient size, and thereforestrength, to support all loads on the joint. Parts shouldnot be permanently deformed or damaged in assemblingthe joint. As pieces increase in size, the strength of thewelds or attachment devices holding them may also needto increase. No temporary attachment should be so rigidthat parts cannot expand and contract in response to heatfrom preheating and welding. Tack welding is the mostpopular method of holding parts to be joined, but tackwelds that are not completely remelted by subsequentwelds, or welded with an approved WPS with the correctpreheat, may cause fatigue cracking problems. Tackwelds are not to remain on permanent material outsidethe finished joint (see C-3.3.7.1). No temporary weldshould be made unless shown on the shop drawings orapproved by the Engineer (see C-3.3.9).


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C-3.3.7 Tack Welds. Annex D, Terms and Definitions,defines a tack weld as, “A weld made to hold parts of aweldment in proper alignment until the final welds aremade.” Tack welds are usually small short fillet welds.However, a tack weld may also be a groove weld used tohold parts together prior to final welding.

C-3.3.7.1 Fillet and groove welds used as tack weldsare subject to all of the requirements of the code, exceptas described in this subclause. Tack welds, because oftheir relatively small size, are frequently subjected tohigh cooling rates that may cause unacceptable harden-ing of the weld and the HAZ. Tack welds sometimes areoverstressed and fail by cracking before the final weldsare made. Tack welds, even when removed by grindingflush, may initiate hydrogen-induced and fatigue cracks.These provisions allow for the use of tack welds underthe most economical conditions without subjecting thestructure to unnecessary exposure to cracking.

(1) When tack welds are expected to be completelyremelted by subsequent welds made by SAW, ESW, orEGW, it may not be necessary to preheat before tackwelding. This exception to code requirements is allowedbecause any unacceptable hardening of the weld or basemetal will be removed by the heat of the subsequentweld. SAW, EGW, and ESW are the only processes thatare allowed this exclusion. FCAW, GMAW, and SMAWalso have the ability to remelt tack welds under limitedconditions, but, because of the smaller energy of theseprocesses, remelting is not consistently performed.

(2) Tack welds that have undercut, porosity, andunfilled craters do not have to be repaired or replaced priorto final welding by SAW expected to remelt the tack,ESW, or EGW. These discontinuities are not expected tocause unacceptable discontinuities in the final weldsbecause the tack weld will be remelted by the final weld.

Slag and cracks are not allowed to remain in or on tackwelds. Slag may contribute to slag inclusions in the finalweld. Cracks are not allowed because they may propa-gate into the final weld or base metal. All welding underthis code, including tack welding, are to be performedusing the hydrogen control provisions found in the code.Tack welds are sometimes found to be cracked beforefinal welding is begun. Other tack welds may crack asthe final welding proceeds, due to expansion and con-traction stresses that result from preheating and welding.In this case, welding is stopped and the cracks repaired.If the weld throat and all of the crack is removed byremelting, no harm is done. However, because it isimpractical to determine the extent of cracks, particularlycold cracks that may extend into the base metal beyondthe penetration of the arc, all cracked tack welds are to beremoved before final welding and the adjacent base

metal is inspected by MT for cracks. If base metal cracksare found, they should be completely removed.

C-3.3.7.2 Tack welds that are not removed prior towelding provide similar strength and mechanical proper-ties as the final weld. When the tack weld is not remeltedin placing the final weld, the tack weld itself is carrying aportion of the load. When the tack weld is completelyremelted into the final weld, the tack weld metal willaffect the properties of the final weld through dilution.Therefore, all tack weld consumables have the qualityand mechanical properties required by the specifications.

Tack welds are to be cleaned thoroughly before makingthe final welds. Tack weld contours affect placement andfusion of subsequent weld passes. Cascading the ends ofmultipass tack welds reduces stress concentrations at theends, and provides a smooth transition and access for thefinal welding.

C-3.3.7.3 Tack welding outside of the final weld jointshould be avoided wherever possible. A tack weld ortack weld removal site may serve as a fracture initiationpoint. The tack weld may not be designed to carry stress,but the presence of the tack weld may cause the weld topick up applied or secondary stresses from service loads.Should the weld become overstressed, or should fatigueoccur, the crack may propagate into other portions ofadjacent welds or the base metal. The HAZ of the tackweld, whether the tack weld is removed or remains inplace, may also have inferior toughness and lead to crackinitiation.

C-3.3.7.4 The HAZ below a tack weld is not consid-ered a potential crack source if it is not excessively hard.Hardness tests can be performed using simple centerpunch comparators. When hardnesses are Rockwell C-30or lower, hydrogen-induced cracking is very unlikely.However, some steels may have higher strengths andhave higher hardness, even without welding. In this case,the hardness of the steel itself is the maximum hardnessallowed in the HAZ. However, some steels have higherhardness prior to welding, in which case HAZ hardnessis limited to the hardness of unaffected base metal.

When the tack weld HAZ has unacceptably high hard-ness, removal of the shallow HAZ below the tack weldshould be performed. Grinding to a depth of 3 mm[1/8 in] below the original surface should remove alltraces of tack welds and their HAZs. Cracks, if found,require further exploration and repair. The yoke methodof MT is recommended for HAZ crack examinationbecause it is easier to perform and causes no arcing of themagnetizing current at the surface.

C-3.3.7.5 It is very important to avoid tack welds thatwill not be incorporated into final welds. Tack welds


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have been a major source of fatigue cracks. Tack weldsshould be made of a size and contour so that they do notinterfere with final welding and cause unacceptable welddiscontinuities. Tack welding inside the joint, andremelting tack welds if possible, will help provide goodfatigue life.

C-3.3.7.6 Tack welds not within the joint and thatremain in place are subject to the requirements for bothtack welds and final welds, including minimum weld size,WPS, preheat and quality. Intermittent fillet welds areprohibited, except in those applications allowed by theEngineer, because of their poor performance in fatigue.Remaining tack welds require the strength and integrityto sustain secondary stresses. Therefore, tack weldsattaching a backing bar are to be continuous or removedin conformance with the requirements of 3.3.7.4.

C-3.3.8 Temporary Welds. Temporary welds should bemade and removed with great care because they are oftensmaller than permanent, or final, welds in size andlength. When the stress range and numbers of cycles ofstress were sufficient in fatigue testing, cracks have initi-ated from sites where temporary welds have beenremoved. The smaller temporary welds provide limitedwelding heat input, causing hardening of the base metalto a limited depth, even though the welds appear to havebeen removed. Even though an approved WPS isrequired, small and even medium size temporary weldsare generally subjected to higher transformation coolingrates, increasing the risk of hydrogen-assisted crackingin the weld or base metal. Because of the lower weldingheat inputs that are common in temporary welds, as com-pared to other welds, higher preheat and interpass tem-peratures should be considered. The hard portion of theHAZ, if any, under a temporary weld is generally shal-low. If grinding is carried to 3 mm [1/8 in] below theoriginal surface during weld removal, and is carefullyfaired-in on a 1:10 slope, there is little chance that theweld removal site will initiate fatigue cracking under anyloading condition. All weld removal sites should be care-fully visually inspected for the remains of fusion defects,notches, and cracks. MT or PT may be used to supple-ment visual inspection (see 3.3.7.3 and 3.3.7.4).

Because of the risk of HAZ cracking and crack propaga-tion in quenched and tempered steels, including Grades485W [70W], 690 [100], and 690W [100W], the use oftemporary welds in tension areas is prohibited.

Temporary welds on exposed weathering steel shouldbe made using weathering steel electrodes. The area ofnonweathering steel electrode may corrode and causestaining.

All temporary welds need to be shown on the shop draw-ings. This enables the planning and inspection requiredfor the use of and removal of temporary welds.

Temporary welds are similar in properties to tack weldsnot incorporated into final welds, covered under 3.3.7.3.Incorporated tack welds and their HAZs usually benefitfrom the heat input of subsequent weld passes, but tem-porary welds do not receive this additional heat input.

C-3.3.9 Joint Root Openings. The root opening dimen-sion controls access for welding in all groove welds withan included angle of 60° or less. When there is less thanadequate root opening, the number and size of fusion dis-continuities can be expected to increase. When there istoo much root opening, in joints that are not made againststeel backing, it is difficult or impossible to bridge theroot opening with sound weld metal. Excess root openingcauses weld discontinuities and allows the degradation ofmolten weld metal in the root because there is insuffi-cient shielding on the far side of the joint. These defects,fortunately, are removed by backgouging and do notbecome part of the permanent weld. In joints made usingsteel backing that have excessive root opening, a single-pass weld at the root may be too wide and thin to sustaintransverse shrinkage stresses, and therefore crack.

Manually controlled open arc WPSs have a greater abil-ity to successfully bridge root openings than fully auto-matic machine-controlled WPSs that weld in a straightline without being programmed to weave. Machine con-trolled WPSs produce stringer beads under the provi-sions of this code, and unless otherwise approved by theEngineer, root openings are limited to a maximum varia-tion of 3 mm [1/8 in] from minimum to maximum, whenmeasured along the joint as assembled for welding. Thisprovision for machine welding applies to both open rootweld joints and joints made against steel backing. Itassumes that machine guidance control is inferior tomanual guidance of the arc. Unacceptable deviations inroot openings are allowed to be repaired by welding orgrinding prior to assembly (see 3.3.4).

C-3.3.10 Assembly Sequence. Groove weld prepara-tions produced by air carbon arc gouging are expected tobe in substantial conformance with the details for J- orU-groove welds shown in Figures 2.4 and 2.5. Thismethod of joint preparation, compared to machining, isexpected to incur minor deviations which are not detri-mental to weld quality. Exactness of details regardingsize and radius are nearly impossible to achieve, there-fore reasonable tolerances should be applied. Othergroove weld details produced by gouging that are sub-stantially different than those shown in Figures 2.4 and2.5 are qualified by test and approved by the Engineerprior to use.


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C-3.4.1 Weld shrinkage stresses are unavoidable, but themagnitude of residual stresses and resulting distortioncan be reduced by careful planning, reducing weld sizes,reducing the yield strength of the filler metal, and reduc-ing the number of weld passes required to produce agiven volume of weld metal. To minimize weld shrink-age stresses, welds should be no larger than necessary.Filler metal yield strength should not significantly “over-match” the base metal, allowing the weld metal to yieldunder residual stress rather than deliver higher shrinkagestresses into the member. High weld metal strengthscause high residual stresses in the weld and adjacent basemetal, and also exhibit lower ductility. Multipass weldsshould be made with no more stringer beads than arenecessary to produce good mechanical properties in theweld metal. Multipass welds are desirable because theyhave improved mechanical properties, but an excess ofsmall weld passes creates additional residual stress. Eachpass requires sufficient heat input to fuse to the adjacentweld and provide a slow enough cooling rate to avoidproblems.

Preheating can help reduce residual stress. The partsexpand from heating before welding and cool more slowly,resulting in a weld area with lower residual tensileshrinkage stresses after the weld cools to ambient tem-perature. Sequence of welding generally has more effecton angular distortion than on total residual stress.

Following solidification, welds and base metal contractas temperatures decrease. Unrestrained, steel contractsabout 2 mm per 100 mm [1/16 in per 4 in] as it cools fromliquid form to a room temperature solid. Steel in the formof austenite, above the transformation temperature, con-tracts at a faster rate than it does after transformation toferrite, pearlite, bainite or martensite. At transformation,there is an expansion that actually reduces the residualstress, but contraction continues as temperaturesdecrease. The effect of all cooling after solidification inwelding is to create net residual tensile stress in the weld,and compressive stress in the steel, whenever restraintis present. The higher the yield strength of the steeltransformation product, the higher the residual stress.Each weld pass causes shrinkage and resulting residualstress.

All welds, regardless of size, produce longitudinal resid-ual stresses equal to the yield strength of the weld. In gen-eral, by the time a weld is 200 mm [8 in] long, it hasdeveloped yield strength residual stresses. These stressesact on the full length of weld. Stress is concentrated atthe ends of welds and where there is a discontinuity orgeometric change in section. When hydrogen-inducedcracking has occurred, weld removal may reveal a patternof underbead cracking at regular intervals along thefull length of the weld. In addition, hydrogen-induced

cracks frequently outline ends of welds where stress isconcentrated.

In addition to longitudinal residual stress, which shouldalways be considered to be at yield strength, there arealso significant transverse residual stresses. Transverseresidual stresses vary depending upon weld size andlocation in the weld. A double V-groove weld, BU-3,may have a transverse tensile stress at the surface of one-third to one-half the yield strength when the weld size is50 mm [2 in] or greater. The larger the weld nugget, thehigher the transverse residual stress. The transverseresidual stress at the center, or root, of a two-sidedgroove weld is a compressive stress. Since weld passesare completed in the root first and all subsequent weldpasses shrink against the resistance of the original weldpasses, welds made by traditional arc WPSs have trans-verse tensile stresses at the surface, welded last, andcompressive stresses at the root. The root of the weld canbe at the center of the weld cross section or at a surface,depending upon the joint detail used. ESW and EGWwelds have the opposite residual stress pattern, becausethey solidify from the edges of the weld pool towards thecenter. This places the center of the weld in tension andthe surfaces in compression.

Attempts to control shrinkage and distortion should bebased upon the effects of residual stress from weldsolidification, transformation, and cooling, and also thestresses and dimensional changes produced by the pro-cess of heat shrinking, or upset shortening. Upset short-ening, thickening and shortening of the material, occursin all weld metal and HAZs that do not remelt under theheat of subsequent passes of weld. The weld and basemetal is heated or reheated by each pass of the weldingarc. Upset shortening is caused by the rapid expansion ofthe steel and existing weld at high temperature, followedby contraction during cooling, with rapidly increasingrestraint, causing localized yielding and thickening of thematerial. It is similar to the phenomena used to camber,curve, or straighten steel bridge members using heat. Inwelding, temperatures are high and the restraint of thesurrounding steel is more than sufficient to produce upsetshortening without any need for preloads.

C-3.4.2 Welds are to be made so that shrinkage does notproduce unacceptable angular distortion in weld joints,or permanent sweep or camber in the member. If equalamounts of weld metal are placed sequentially on eachside of an initially unrestrained, two-sided weld, the firstside weld will cause more angular distortion than thesecond side weld, which is then restrained by the first.The result of welding with equal weld volumes on eachside of a two-sided butt joint groove weld, for example,is noticeable and perhaps unacceptable angular change,unless the parts were either angled slightly before weld-


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ing in anticipation of this condition, or restrained againstrotation (see C-2.1.2). If butt joint groove welds madewithout restraint or initial compensating misalignmentare to be straight after welding, either the second sideweld volume needs to be considerably larger than thefirst side weld or weld passes need to alternate sides.Typical estimates for differential weld volumes to pro-duce straight butt joints indicate that a second side vol-ume between 50% and 100% larger than the first, orbetween a 60–40 and a 67–33 split, depending upon jointdesign and restraint, is needed. If the first side weldcauses serious angular distortion, unbalanced welding onthe second side may not be able to bring it straight, andmay result in extremely high residual stresses, base metaldeformation, or even hot “restraint” cracking.

For small assemblies, alternating weld passes betweenopposite sides may reduce deformation and residualstresses, but this is not practical for flanges or other largeweldments.

Longitudinal welds not located about the center of grav-ity of the cross section induce sweep or camber, or both,in the member. Longitudinal shrinkage and distortion aremore difficult to estimate because weld size, memberstiffness, distance from welds to the member’s center ofgravity, and sequence of welding have an effect. Goodweld design and sequencing considers balancing weldsabout the center of gravity of the cross section, and plac-ing the welds in a pattern that will minimize curving andtwist of the member.

C-3.4.3 Distortion control and avoidance of shrinkagestresses that can lead to cracking or lamellar tearingrequire planning, including the selection of the weldprocess, filler metal, and joint details to be used. Theseitems should be indicated on the shop drawings and inthe WPS. Where shrinkage and distortion are likely to bea problem, a special weld sequence drawing should beprepared listing all steps necessary to control joint ormember distortion. The Engineer should be providedwith this information, but approval is not required.

C-3.4.4 When welding is done from points that are rela-tively fixed toward points that are unrestrained, trans-verse weld shrinkage stresses may be used to bring largeparts into alignment. Welding from the fixed portiontoward the free end in built-up members, typically fromthe center outward, reduces the risk of buckling and theseparation of parts from member distortion caused byweld shrinkage stresses. Made in this manner, the cool-ing of the welds at the ends causes a longitudinal com-pressive effect near the center of the member, helpingoffset the accumulation of tensile shrinkage stresses nearthe center. If the ends of a part are joined first, the weld

near the center is more restrained, increasing the risk oftransverse shrinkage cracking.

C-3.4.5 Shrinkage from one weld may have a majoreffect on other welds or member components. Weldsshould always be made with the minimum reasonablerestraint that is consistent with production and dimen-sional requirements. The weld metal is designed to sus-tain yield strength residual stresses without cracking.The base metal is often first to fail in situations of highrestraint and high residual stress. When stresses are in thethrough-thickness, or “Z” direction, lamellar tearing canbe a serious problem.

The sequence of welding joints should be considered.Generally, joints with high restraint or high shrinkageshould be welded first, followed by joints with lessrestraint and shrinkage. Should the joints with lesserrestraint be welded first, the more difficult joints mayhave even more restraint than if welded first. Spacingmaterials in the joint, particularly at the root, have beenused successfully in some cases to provide allowance forweld shrinkage.

C-3.4.6 When cover plates, flanges, and longitudinalstiffeners are completely joined full length before beingwelded to their respective beams or webs, residualstresses are kept to a minimum. The butt joints arewelded without longitudinal restraint, so the residualstress from the subsequent longitudinal welds is notadded to the transverse residual stresses created by thewelds used to join the member components. When alllongitudinal components are joined before being weldedinto their final cross section, there is better access forwelding and weld quality is often improved.

Long members may be spliced by welding in the shop orfield. Splicing of finished full section members willgenerally be done by welding in a single transverseplane as described in 2.17.6.2. Welding in this mannerrequires special care because of the large sections, highrestraint, and triaxial stresses present. Special care isneeded to avoid cracking near weld access holes becauseof residual and applied stresses that may be concentratedby the change in section. If the access hole is finished toremove all notches that concentrate stress, and if alluntempered martensite produced by thermal cutting isremoved from the surface of the access hole by grinding,unfilled access holes may provide satisfactory fatigueperformance.

C-3.4.7 Partially completed welds may crack if allowedto cool-down before the weld is complete. This is partic-ularly true for small initial root passes when the partsbeing joined are both large and highly restrained. The


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cracks that occur may be hydrogen-induced, but they aremore likely to be shrinkage cracks from thermal changesor increased restraint. Shrinkage cracks may formbecause the weld is under severe stress, but the elevatedtemperature of the weld or HAZ has reduced the strengthof the material below what is required to resist cracking,although hot weld material is generally quite ductile.With hydrogen-induced cracking, the weld region hasnot been allowed to remain at elevated temperature longenough to diffuse sufficient hydrogen from the weld andHAZ. When welds are completed before cooling isallowed, there is more weld metal to share the stress andthe weld and HAZ is hot for a much longer period. Inaddition to the benefits of more time at temperatures thatfacilitate diffusion of hydrogen, steel temperatures above200°C [350°F] make hydrogen-induced cracking almostimpossible. Completed multipass welds have more weldpasses that have contributed to the improvement by heattreatment of formerly deposited passes.

C-3.4.8 Members distorted by welding may be straight-ened by either or both of the described methods withoutprior approval of the Engineer. When heat straighteningis performed, care should be taken to avoid overheatingthe steel. The maximum heating temperatures that arespecified are near the transformation temperature of thesteel. Exceeding the transformation temperature wouldproduce a change in the mechanical properties of thesteel. A margin of safety is provided to ensure that thetransformation temperature is not exceeded, and themeasurement of the actual steel temperature during heat-ing is necessary. Parts to be heated for straighteningshould be free of applied load. However, the code doesnot prohibit the use of restraints or mechanical straight-ening forces applied as a part of the heat straighteningprocedure. Combining mechanical forces with heat mayincrease the amount of angular change produced by eachheating pattern by a factor as high as four, as the amountof compressive upset shortening is increased at highertemperatures. Heat straightening, even when done withmechanical force, is not the same as hot bending. Hotbending is localized bending using force, taking advan-tage of the reduced strength and increased ductility ofsteel at very high temperatures, to adjust steel to a partic-ular configuration or location using less force. Mechani-cal methods such as press bending or “cold gagging”may also be used. However, research on bridge repairindicates that less damage is done to the steel by heatstraightening than by mechanical straightening usingforce alone. All straightening methods may reducetoughness and ductility of weld and base metal to somedegree. Heat straightening methods cause the leastamount of reduction in toughness and ductility. Coldbending of FCM is prohibited (see 12.12).

C-3.5 Dimensional TolerancesC-3.5.1 The dimensions of structural members con-structed under this code are governed by the provisionsof this subclause and the requirements of the contractdocuments. Structural steel ordered from the millsshould be delivered in conformance with the dimensionaland quality requirements of AASHTO M160M [M160](ASTM A 6M [A 6]). Once the steel has been subject tofabrication or erection by welding, the dimensional pro-visions of AASHTO M160M [M160] (ASTM A 6M[A 6]) are superseded by the provisions of this subclauseor the contract documents.

Camber measurements to determine conformance withthis subclause are usually made when the steel is in theno-load condition (see 3.5.1.3). When this cannot beaccomplished, suitable adjustments may be included fordead load deflections.

C-3.5.1.1 The equations listed give the maximum off-set from a straight line that would represent a perfectlystraight member. Straightness should be measured aboutboth the strong and weak axes of the member. These pro-visions are to provide safety against buckling of com-pression members. No provision is made for localdeviations. Deviations from a straight line should begradual and the maximum deviation should be near themiddle of the member.

C-3.5.1.2 This equation provides tolerances for themaximum deviation from a straight line that would rep-resent a beam or girder, regardless of cross section, thathad no specified camber or sweep. For beams and girderswith a specified camber, see C-3.5.1.3. Camber devia-tions are vertical displacements from the specified no-load condition. Sweep deviations are horizontal displace-ments from a perfectly straight alignment. There are noprovisions for localized abrupt changes in alignment.Deviations from a perfectly straight vertical and horizon-tal alignment are expected to be gradual.

C-3.5.1.3 The tolerances for beams and girders thathave specified camber are divided into two categories.The second set of tolerances is applicable when the topflange is embedded in concrete and a designed concretehaunch is not used. A “design concrete haunch” may bedefined as the use of additional concrete above the top ofthe beam or girder flange to adjust for elevation, with agiven concrete depth between steel flange and the under-side of the concrete deck. The first set of tolerancesapply for those cases where the top flange is not embed-ded in concrete, and those that employ a designed con-crete haunch. The tolerances of the second set areestablished as a plus or minus from specified camber.In the first set of tolerances, there is no provision for


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negative or inadequate camber. Instead, the tolerance isapplied as a plus only tolerance. The physical sum of thetolerances is the same for both sets, 40 mm [1-1/2 in] forlonger spans, and 20 mm [3/4 in] for shorter spans, asdefined. Tolerances are applied to the span length (bear-ing to bearing) of the girder line, not individual girders inthe line.

The tolerances were first developed for bridges con-structed with a minimum bridge deck design haunch of50 mm [2 in]. When bridge deck slabs are designed inthat manner, excess, positive, upward camber up to50 mm [2 in] can be accommodated during construction.Excess camber in amounts less than the haunch heightwould cause no difficulties with the bridge slab or othercomponents, provided adjacent members had similarcamber profiles. The camber tolerance is +40 mm [1-1/2in], with the remaining 10 mm [3/8 in] provided as a con-tingency for other field deviations (see Figure C-3.5).

The tolerances are applied at the lay-down stage whenmembers are pre-assembled for drilling holes for fieldsplices or preparing joints for field welded splices. Thetolerances are measured as the offset between the arc ofthe specified camber and the location of the steel. Thearc is based upon an assumed typical uniformly distrib-uted loading case which causes a parabolic deflectedshape.

Not all camber is permanent. As residual stresses are dis-sipated, in time, due to applied handling and live loads,the profile of the steel changes. Camber produced byweb cutting is most permanent and is the primary methodof cambering bridge members provided in the code (see3.2.7). Camber induced by heating is subject to camberloss, especially prior to deck placement, with the amountof loss dependent upon the maximum ordinate and theheating method used, and is allowed only for the correc-tion of camber. Members that are heat curved maychange camber as a result of heat curving. Extra cambershould be cut into the webs of members to compensatefor losses from residual stress dissipation and weldshrinkage effects. The greatest change in camber oftenoccurs when cutting the web plate to size. Stress frommill rolling may be released at that time and substantialcamber change, both plus and minus, can occur. This canbe minimized by precutting the plate before cutting tofinal size. This camber change is most significant whencutting two pieces from a larger plate. Other camber losscan, in most cases, be controlled by the moderate addi-tion of camber in the cutting pattern. This extra camber isusually determined by the “intuitive” judgment of shoppersonnel.

The camber specified should allow ease of constructionand not negatively impact function or aesthetics. Excess,

positive, upward camber rarely causes any problem inconstruction, provided the deviations from specifiedlines are gradual and the maximum deviation is not solarge that the steel intrudes into the design slab or is mis-aligned with connections to adjacent members.

C-3.5.1.4 This subclause provides a method of calcu-lating the maximum horizontal deviation from a speci-fied sweep. The maximum deviation is expected to benear the center of the piece or assembly, unless otherwisespecified on the design drawings, and deviations areexpected to be gradual rather than abrupt. Deviationfrom specified sweep in horizontally curved bridgemembers is measured as the deviation from the specifiedhorizontal curve shown on the approved drawings. Thisdoes not require uniform curvature or preclude “chord-ing” due to heat cambering at intermediate points, pro-vided the member stays within the tolerance limits. Mostbridge members are flexible and allow some lateraladjustment during erection without damage. Box mem-bers are much stiffer than I-shaped members. Deviationfrom specified sweep should not be so large that it is dif-ficult to align connecting members and cause damage tothe steel during erection.

Flange plates are often thermally cut from wider plates.It is recommended that both edges of plates are cut simul-taneously to maintain balanced heat. Failure to do so mayresult in undesirable sweep or twist in the flange plates.

C-3.5.1.5 This is a historic workmanship standard thatalso represents good design. The web location may devi-ate 6 mm [1/4 in] to either side from the center or otherspecified location at the flange.

C-3.5.1.6 The provisions for web flatness are basedupon aesthetics and relative freedom from web bucklingand are contained in 3.5.1.6(1)–(4). Measurement ofweb distortion considers the curvature of the memberand deducts the curvature arc from the actual distortiondimension.

Thin girder webs and large stiffener welds worsen theproblem of web distortion. Each web panel is boundedby four welded sides that shrink. It is difficult to correctweb distortion without leaving unsightly marks. Heatcurving members with heavy, wide flanges and radiiunder 300 m [12 in] can create severe web distortion, or“oil can” effects. For these cases, precutting or precurv-ing the flanges before assembly to the web will reducethis effect.

The provisions for out-of-flatness of girder webs at endswith bolted splices are found in 3.5.1.6(3). This provi-sion allows twice the maximum out-of-flatness allowedelsewhere in the girder. At such locations at the end ofthe web, it is common to find more extensive distortion.


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At the end, there is no lateral support for the web prior toassembly of the bolted splice. Lateral displacements of100 mm [4 in] or more are possible in deep girders. Thiscondition is produced as a result of welding around threesides of relatively thin web panels, and leaving the fourthside unrestrained. Temporary elastic distortions of thistype should not be cause for repair. The high strengthbolts in the web connection will usually straighten theweb to within tolerance without damage to the memberor its connections.

C-3.5.1.6(2) Flatness of Girder Webs. In addition tothe dimensional tolerances based upon workmanshipstandards provided in 3.5, these requirements for the flat-ness of girder webs are intended to avoid initiating webbuckling under anticipated construction or service condi-tions, and are also intended to ensure the aesthetic qual-ity of the bridge. These tables reflect values tabulatedusing the flatness tolerance formulas.

Web distortion is exacerbated by using thin web plates,using fillet welds that are larger than necessary to attachany intermediate stiffeners and connection plates, and byheat curving of girders to short radii after the completionof welding. Some designers consider 10 mm or 12 mm[3/8 in or 1/2 in] to be the minimum plate girder webthickness to avoid significant distortion and avoid theneed for large numbers of transverse intermediate andlongitudinal web stiffeners.

Most bridge girders have a web depth of 1200 mm[48 in] or more. While 8 mm [5/16 in] fillet welds arecommonly used to attach intermediate stiffeners and con-nection plates, 6 mm [1/4 in] fillet welds are typicallybetter for the connection of one-sided intermediate stiff-eners to the webs of fascia girders. Welds of this sizereduce the amount of stiffener “reflection” distortion thatoccurs in the unstiffened side of fascia girders that isgenerally exposed to public view.

The material savings gained by using web stiffeners toallow reductions in web thickness are often more thanoffset by the increased labor costs necessary to install thestiffeners, and to make corrections to the web distortionthat may result. Serious web distortion may occur duringheat curving, or by the improper use of heating torcheswhen preheating for welding. Unstiffened areas of girderwebs should be protected from concentrated, high inten-sity heat. To reduce lateral distortion when correctingdistortion by heat-shrink methods, heating should bedone near intermediate stiffeners or connection plateswhenever possible. If care is not taken, the heating pat-terns may cause distortion that will remain visiblethroughout the life of the structure.

C-3.5.1.6(3) Excessive Distortion. Ends of girderwebs that are not stiffened have very little resistance to

lateral distortion. The distortion is caused by web panelperimeter shortening, the result of welding to the top andbottom flanges and to stiffeners on one side of the endpanel, but not at the free end of the girder. Lateral dis-placements of several millimeters have been observed atthe field splice ends of deep girder webs. These displace-ments, when straightened and stiffened by bolted webconnections, are almost always temporary and of nostructural significance. This subclause allows displace-ments of twice that provided in 3.5.1.6(2). Thin spliceplates may not have enough stiffness to bring a highlydistorted web back within tolerances of 3.5.1.6(2). Pro-vided the high-strength bolted splice pulls the web intoposition without unusual force, there is no damage to thegirder. Generally, very little force is necessary. Althoughthe web-ends may have the distortion allowed by thissubclause when each girder segment is in the web-verti-cal position, adjacent webs and their splice places arebrought into common alignment prior to shop drillingsplices. Drilling holes with the webs fully displaced tothe allowable tolerances would lock those displacementsinto the completed structure. For large segment displace-ments, special field bolting and pinning may be neededto bring webs and splice plates together before routinebolt tightening is performed.

C-3.5.1.7 This is a historic workmanship provisionthat has produced good results. To produce a memberthat has the web square, the web should be normal to theflange before welding. Fixturing the flanges against rota-tion during welding and sequencing the welding to avoidrotation are also helpful in providing a square joint. Mul-tipass welds should be deposited in a manner that willbalance shrinkage stresses on each side of the web-to-flange weld. Generous tilt tolerances are provided forlocations between bearing points, except that parts to bejoined by welding or bolting need to align in assembly.The flanges need to be approximately square with theweb, or at least have the same tilt as the adjacent pieces,where splices are to be made (see Figure C-3.6).

At bearing points, the flanges should be normal andsquare to the web. Bearing stiffeners simplify fabricationof flat bearing surfaces, particularly when combined witha mill-to-bear and fillet welded bearing stiffener-to-flange joint (see 3.5.1.9).

C-3.5.1.8 These dimensional tolerances have pro-duced good results and are considered reasonable work-manship tolerances. The strength variation caused bysuch tolerances is nominal.

Bridge seats are provided an elevation tolerance, bearingheights have a tolerance, and fabricated steel membershave both camber and depth tolerances. The result, aftererection, is that the top of steel may not always be


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exactly at the elevation shown on the plans. However,this seldom causes difficulty in construction or use.Where the maximum of these combined tolerances is notacceptable, tighter limits should be noted on the plans.The use of shims may also alleviate problems with mem-ber elevation.

Web depth tolerances at welded member splices mayrequire tighter tolerances than that provided in this sub-clause. The adjustment for depth variation through thealignment of parts is limited as described in 3.3.3.

C-3.5.1.9 Bearing loads are expected to be carried bysteel parts that bear upon each other. Bearing does notnecessarily mean full contact, but is as close as specified.It is not essential that the parts bear completely before allloads are applied. The applied loads can close very smallgaps and the elastic or plastic strains on adjacent welds areof no consequence, provided the steel components fit asspecified. Stiffeners should bear after the dead load hasbeen applied (see Figure C-3.7).

When bearing stiffeners are used, at least 75% of thebearing stiffener area bears against the top of the bottomflange.

For girders using bearing stiffeners, at least 75% of thebearing area directly below the web and stiffeners isexpected to be within 1 mm [1/32 in] of the supportingseat or base. The flange not directly below the web andstiffeners need not be within this tolerance.

For girders without bearing stiffeners, the area beneaththe web is expected to be within 1 mm [1/32 in] of theseat or base. In addition, the flange is not curved or bentto place the bearing contact area at the edges of theflange rather than beneath the web.

C-3.5.1.10 Intermediate stiffeners are intended to pre-vent web buckling. They may also brace the flanges dur-ing handling and transportation and help avoid webcracking caused by flange rotations about the web due tothose operations. It is not essential that intermediate stiff-eners have a mill-to-bear fit upon adjacent flanges. Asmall gap of up to 2 mm [1/16 in] is allowed. Most inter-mediate stiffeners are cut to length slightly less than theexact distance between flanges, then placed tight againstthe tension flange and welded to the compression flange.When the stiffener is not welded to the flange, weldshrinkage may cause the stiffener to pull slightly awayfrom the flange. The flange may also rotate away from astiffener that was originally in contact. A slight separa-tion is not structurally detrimental, but may be a corrosionproblem if not properly protected. A tight fit of stiffenersmay be beneficial in maintaining squareness of flanges(see 3.5.1.7).

C-3.5.1.11 This is a reasonable workmanship stan-dard. Removal of a bowed or out-of-alignment stiffenerthat may exceed this limit should be weighed againstadded web distortion and other fabrication problemsincurred during the repair (see 3.7.5).

C-3.5.1.12 Bearing stiffeners act like columns, fixedon one side and unsupported on the other. Bearing loadsare transferred from the girder web to the flange throughthe stiffener. Eccentricity, caused by lack of straightness,is undesirable. Bearing stiffeners may be perpendicular toflanges or truly vertical, subject to contract requirementsand alignment considerations, especially on skewedstructures. Because bearing stiffeners concentrate bearingforces at designated locations on the seat or base below,the location of the bearing stiffeners is critical.

C-3.5.1.13 When special dimensional tolerances arerequired, they should be described in the contract docu-ments. Tolerances may be established for structural,workmanship and aesthetic reasons. Some toleranceshave a major effect upon whether or not pieces will fittogether properly during erection, others affect how thestructure will function and others affect appearance. Allspecial requirements for dimensional tolerances shouldbe based upon the needs of the individual structure.

Because it is difficult to specify properly, and becausethe effect of twist varies greatly depending on the type ofmember and its application, a tolerance on twist is notprovided in this subclause. Twist of box members, some-times 1000 times more torsionally stiff than I-shapemembers, may seriously affect ease of erection and sec-ondary stresses. Most twist problems are a result of poorassembly. The best way to avoid problems in the con-struction of box members is to fit the box properly andhold it in position firmly while making the corner weldsin a sequence that will balance shrinkage stresses. Forbox girders, elements are expected to be straight or havematching curvature or camber prior to assembly. That is,the top and bottom flanges should match and the websshould match each other. Internal diaphragms also help tokeep box members free of twist and aid in their assembly.

It is extremely difficult to straighten unacceptable twistin box members. Often the only solution is to remove thecorner welds, reposition components and replace thewelds. If there are problems with dimensional tolerancesof finished members, the Contractor should proposesolutions for approval by the Engineer.

C-3.5.1.14 Faying (contact) surfaces of adjacentmembers to be connected by high strength bolted splicesshould be nearly co-planar to avoid requiring spliceplates to be excessively distorted in their weak, through-thickness direction. Fills of 2 mm [1/16 in] or less aredifficult to blast, prime and assemble without damage or


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distortion. The clamping force of the bolts is able to cor-rect slight angular misalignment, but cannot significantlydistort splice plates without straining the splice beyondyield. When the splice material is too thick to bend intocontact, a poor connection may be produced. Whenexcessive bending of splice material occurs, the splicemay be damaged. Filler plates are allowed to compensatefor differences in thickness at bolted connections, unlessotherwise provided in the contract documents.

C-3.5.1.15 For secondary members, additional bend-ing of splice material is allowed because the potential forfuture fatigue damage is less and failure would not jeop-ardize the overall structure.

C-3.5.2 The assembly and fit-up tolerances of 3.3 apply.Conformance to these requirements is facilitated by shopassembly or by preparing the joint to a template.

C-3.6 Weld ProfilesRules for acceptable weld profiles have been establishedto ensure good workmanship and to avoid unnecessarystress concentrations.

C-3.6.1 Fillet welds’ shape should not create excessivestress concentrations. Excess convexity can concentratestress at the weld toes. Excess concavity creates surfaceshrinkage stresses at the center of the weld face that maycontribute to throat cracking. Ideally, fillet welds shouldappear as shown in Figure 3.3(A). Welds conforming tothe requirements of Figure 3.3(B) are acceptable pro-vided the convexity limits have not been exceeded.Welds shown in Figure 3.3(C) are not acceptable if theyexceed the limits of convexity, undercut, overlap andsize.

C-3.6.1.1 The maximum convexity of a fillet weldand of individual fillet weld passes is a workmanshipstandard.

C-3.6.1.2 At the very end of fillet welds, because ofsurface tension and the inherent nature of starting andstopping the weld, it is extremely difficult to producecompletely acceptable weld profiles. Where an intermit-tent fillet weld is used, the weld profile may deviate fromthe specified profile for a short distance at the beginningand end of the weld, provided the deviation is locatedoutside the required length of weld. Undercut in excessof code requirements and significant weld discontinuitiesare still not be allowed, even if outside the effectivelength of the required weld.

C-3.6.2 Except as noted in 3.6.3, the faces of groovewelds in butt joints and the outside face of corner jointsshould be made with slight reinforcement, but limited to

3 mm in height, even when the specifications require thejoint to later be ground flush. This ensures that there isno underfill and that full effective size has been produced.Groove welds in T-joints and the inside face of cornerjoints are reinforced with fillet welds (see Figures 2.4and 2.5, Note 6). Excessive reinforcement may be anindication of improper weld procedure or technique thatshould be corrected. The weld metal should transitionsmoothly into the base metal, and there should be nosurface notches to concentrate stress or hinder effectivevisual inspection. Figure 3.3 shows acceptable and unac-ceptable groove weld profiles.

C-3.6.3 All groove welds in butt joints required to beflush are finished flush or to a smooth transition betweenparts of different thickness. The code allows the basemetal or weld to be reduced in thickness by 5% of thethickness of the thinner part joined, or 1 mm [1/32 in],whichever reduction is less. A surface considered flushmay also be up to 1 mm [1/32 in] in height above thesurface.

C-3.6.4 When the surface is required by the Engineer tobe finished, surface roughness measurements limitationsare applicable. Surfaces finished to between 3 µm and6 µm [125 µin–250 µin] have the finishing lines parallelto applied stress. This requirement is applied to all welds,but has little effect upon the performance of welds carry-ing only compression. Welds finished equal to or lessthan 3 µm [125 µin] may be finished in any direction. Forwelds in butt joints carrying applied tensile stress, themaximum surface roughness is 3 µm [125 µin].

C-3.6.5 Overlap creates a stress concentration at the toeof the weld. Overlap may have a significant effect onfatigue life when normal to the applied stress, such asreinforcing fillets on CJP groove welds in corner and T-joints in tension. Overlap also makes it more difficult tomeasure weld size, verify fusion, and perform visualinspection.

C-3.7 RepairsC-3.7.1 Weld metal and portions of the base metal maybe removed by any process that will not permanentlydamage the steel and weld which is to remain. Soundweld and base metal should not be removed unnecessar-ily (see C-3.2.6 for restrictions on the use of thermal cut-ting and air carbon arc gouging). Cut surfaces arethoroughly cleaned before initiating, or continuing, arepair. Repair welding is done using an approved WPS.

Because repair welds are often made under conditions ofsevere restraint, techniques important to make a goodweld in the original construction should be followed with


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even greater care during repair welding. When the weldrepair WPSs has a lower heat input than the WPS used tomake the original weld, or when the repair weld is a rela-tively small localized weld, preheat and interpass tem-peratures higher than those used in production weldingshould be considered to prevent excessive hardening ofthe weld or HAZ.

C-3.7.2 When unacceptable weld discontinuities arefound, the Contractor has the option of either repairingthe weld or weldment or providing a complete replace-ment. Without the approval of the Engineer, the Contrac-tor does not have the authority to remove or repairunacceptable welds or base metal with certain types ofcracks, weld discontinuities or base metal discontinuitiesas described in 3.7.4. The repaired weld should conformto the requirements of the original contract documents,and is subject to the same inspection and acceptance cri-teria as the original weld. All routine repairs by weldingare expected to conform to the requirements of 3.7.2.1through 3.7.2.4.

C-3.7.2.1 Overlap or Excessive Convexity.Removal of excess weld metal may be done by air car-bon arc gouging, machining, chipping and grinding, orgrinding. Gouged or cut surfaces should be cleaned andfinished by grinding (see 3.2.6).

C-3.7.2.2 Excessive Concavity of Weld or Crater,Undersize Welds, Undercutting. Prior to welding, thesurfaces are expected to be cleaned in conformance with3.11.1. Additional welding, following an approved WPS,is then performed to provide the proper weld size andprofile.

C-3.7.2.3 Excessive Weld Porosity, Excessive SlagInclusions, Incomplete Fusion. It is important toremove these weld discontinuities. However, to reducethe number of small repairs, it may be preferable to allowsome minor acceptable discontinuities to remain in place.Visual inspection is generally adequate for these discon-tinuities, however MT or PT may be used to supplementvisual inspection in unusual situations. Caution shouldbe used with PT, because the dye and developer maycause weld discontinuities if not completely removedbefore the continuation of welding. Elevated steel tem-peratures may also reduce the effectiveness of PT. If theweld joint is properly prepared for welding, accessibilityis usually sufficient for cleaning using cleaner, clothsand brushes. Prior to welding, the surfaces are expectedto be cleaned in conformance with 3.11.1. Repair weld-ing, following an approved WPS, is then performed toprovide an acceptable weld.

C-3.7.2.4 Cracks in Weld or Base Metal. It isimperative that all of the crack be removed. An addi-tional 50 mm [2 in] of weld or base metal is removed at

each end of the crack to be sure that the entire crack isremoved, because the actual tip of the crack may be hardto determine, and very tight cracks may extend beyondwhat is visible or detectable with NDT. Good lighting isessential and magnification may be used. Because it doesnot contaminate the joint and may be used at elevatedtemperatures, MT is generally the best supplement tovisual inspection to be sure that all of the crack isremoved, but PT or other NDT methods may be used.

Crack excavations should have a contour and profile thatis suitable to provide the joint preparation for repairwelding. In cross section, the excavation should have aminimum root radius of 6 mm [1/4 in] and the sidesshould each be beveled back 15° minimum. In longitudi-nal section, the excavation should be sloped to the sur-face at each end with a 45° minimum slope.

Prior to welding, the surfaces are expected to be cleanedin conformance with 3.11.1. Repair welding, following anapproved WPS, is then performed to provide an accept-able weld.

C-3.7.3 During the course of fabrication and transporta-tion, members may become damaged beyond the scopeof traditionally encountered welding induced distortionand shrinkage. When such damage occurs, the membersmay be mechanically straightened or heat straightened asapproved by the Engineer. Caution should be exercisedthroughout either process to prevent additional damage.Observe the parameters detailed in 3.4.8 relating to tem-perature limits for localized application of heat.

C-3.7.4 The Engineer’s approval is required before cer-tain types of repairs to base metal and welds can be initi-ated. These conditions are potentially more serious thanroutine repairs, therefore careful planning in preparationfor repair welding is needed.

All repairs to base metal, other than those edgediscontinuities described in 3.2, require the Engineer’sapproval, providing notice of unusual discontinuities inthe base metal or lamellar tearing. Internal discontinui-ties in ESW and EGW joints usually require more exten-sive repairs than surface discontinuities or burieddiscontinuities in welds made by other processes, in partbecause ESW and EGW processes are usually used inthicker materials. The weld repair may, under unusualconditions, exacerbate grain boundary fissuring or causethe coalescence of small grain boundary cracks thatalready exist. ESW and EGW joints are also more diffi-cult to accurately evaluate by UT. When necessary torevise the design to compensate for weld or base metaldeficiencies, the Engineer is to be notified and approvethe proposed redesign, reinforcement, or repair method.


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C-3.7.5 Cutting apart of completed welds in completelyassembled and welded pieces may damage the materialthat is to remain. The Engineer is to be notified prior tocutting apart welded joints and attachments so that thestructural integrity of the framing can be checked, andenables the Engineer to work with the Contractor toensure that the problem does not reoccur.

C-3.7.6 If a defective weld or other defective condition ismade inaccessible by subsequent work, it may be neces-sary to take the member apart so that the defective condi-tion can be properly repaired. The Engineer approves theprocedure for disassembly and repair. If preferable tochange the design to compensate for the deficiency, theEngineer first approves the revised design and repairprocedure.

C-3.7.7 Welded Restoration of Material with Mislo-cated Holes. Fatigue cracks and fractures have initiatedin improperly repaired, or disguised, mislocated rivet andbolt holes. When possible, the best repair is to leave thehole open or to fill it with a high-strength bolt. Preten-sioning of the high-strength bolt, with washers under thebolt head and nut if needed, may help to restore the buck-ling strength of compression elements or extend the fatiguelife around holes in some tension members. Mislocatedholes can be successfully repaired by welding if the pro-visions of this subclause are followed, but repair of holesby welding is time-consuming and difficult.

Preparing the hole to provide access, welding longitudi-nal rather than circular beads, and UT or RT can reducethe risk of inclusions. An effective way to repair a holeby welding is to make an elongated excavation to allowgood fusion throughout the full length and cross sectionof the repair weld, then weld using stringer bead tech-niques. Temporary steel backing may be placed withinthe hole to support the first side weld. After the first sideweld is completed and before welding the second side,the root should be gouged to sound weld metal. Grindingthe surfaces flush is also important to reduce stressraisers.

C-3.7.7.1 Statically loaded tension members, andcompression members whether subjected to static ordynamic loads, may have mislocated holes repairedunder certain restrictions. A special repair WPS is to befollowed, and UT or RT of the completed repair, asrequired by the Engineer, is performed.

C-3.7.7.2 When base metal is subject to dynamic ten-sile stress, fatigue crack initiation and growth is morelikely if the repair is improperly performed, and there-fore more care is necessary in the repair of mislocatedholes. The Engineer is notified for approval of both therepair method and the repair WPS. Weld quality is veri-fied by either UT or RT, whichever is specified in the

contract documents for other tension groove welds or bythe Engineer for the repair.

C-3.7.7.3 When mislocated holes in quenched andtempered steels are to be repaired by welding, these addi-tional provisions apply:

(1) Welding is done with filler metals and a repairWPS that will produce weld metal with appropriatemechanical properties, without adversely affecting themechanical properties of the base metal.

(2) The Contractor prepares test samples using therepair WPS before making repairs to the structure.

(3) The quality of the test samples satisfies the RTquality requirements for welds subjected to tensile stress.RT is required, without UT as an option, because RTgives excellent results and produces a permanent record.The Engineer may also require UT in addition to RT [seeC-3.7.7.2(2)].

(4) Mechanical tests are performed to verify thatthe repair welds will be sound and that the weld metal,HAZ and base metal will have satisfactory mechanicalproperties. The minimum mechanical properties of thetested material are the same as the properties for the steelspecified.

C-3.7.7.4 When all repair welding is completed andbefore NDT is performed, the surfaces are made flush asrequired in 3.6.3. Grinding may be required to achievethe flush condition.

C-3.8 PeeningC-3.8.1 Peening is the mechanical working of a weldsurface by hammering with an appropriate peening toolto create a compressive stress at the surface. Peening isnot required for ordinary welds, but is generally reservedfor repair welding or highly restrained joints. The Engi-neer can approve the use of peening which, when prop-erly controlled, may reduce the risk of cracking orlamellar tearing and extend fatigue life. Peeningstretches the metal surface, and because the surface ismechanically elongated, the residual stress at that loca-tion changes from tension to compression. Since cracksdo not initiate or propagate in the absence of tensilestress, cracking is prevented or delayed until a tensilestress from subsequent welding or applied loading over-comes the residual compressive stress.

Peening should be done with a blunt, round tool that willnot nick or tear the surface. A 6 mm [1/4 in] radius on thetool is required unless otherwise approved. When thispeening tool is used, peening impressions appear similarto large Brinell hardness impressions in soft steel.


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Peening energy should not be directed against the fusionboundary or the base metal when using this tool. Basemetal is not generally peened, since its surface may bedamaged and not subsequently reconditioned by a weld-ing bead. The weld metal is more homogeneous (isotro-pic) than the base metal and generally has greatertoughness and ductility. Because of surface profile, onlyconvex weld metal surfaces should be peened. The rootand final layers should not be peened because of theadverse effect of the indentations that may remain. Theadverse effect of indentations are not a concern in inter-mediate weld passes because the layer is remelted andreheat-treated by subsequent weld passes. In addition,root passes are not to be peened because they may crack.

Peening should be done only at temperatures between65°C and 260°C [150°F–500°F]. Higher temperaturesmay damage the steel and cause cracking because ofreduced ductility at temperatures in the “blue brittle”range. Effective peening may be done at much higherforging temperatures, but there is no provision for suchtreatment in this code.

All peening equipment needs to operate without contam-inating the joint with oil, moisture, or other materials thatwill interfere with the continuation of welding. When itis suspected that peening has contaminated joint surfaces,the joint should be thoroughly cleaned before the contin-uation of welding.

C-3.8.2 Use of general weld cleaning hammers, needleguns, and tools, including pneumatic and other impacttools used to remove weld slag, is not considered peen-ing. Peening should only be done using equipmentapproved for that purpose and when part of an approvedWPS.

C-3.9 Caulking

Caulking of welds consists of hammering of the weld oradjacent base metal surfaces to close and hide cracks,porosity, laminations, and other discontinuities in thesurface, and is prohibited.

C-3.10 Arc Strikes

An arc strike may be a weld slash across the steel surfaceor an aborted arc start. Arc strikes may also occur atgrounding locations when clamps are not properlyinstalled. Arc strikes result in heating and very rapidcooling. When located outside the intended weld area,these may result in hardening or localized cracking, andmay serve as potential sites for initiating fracture. Arc

strikes may produce surface discontinuities and hardHAZs.

All welding allowed by the code is based upon stablewelding conditions designed to produce sound fusionand a uniform heat input. Arc strikes may produce littleif any fusion and have extremely variable low weldingheat input. Arc strikes are removed by shallow grinding,including the HAZ, when the arc strike will not be com-pletely remelted by a subsequent weld pass.

The HAZ below an arc strike may be considered a poten-tial crack source if excessively hard. Cracks, if found,require further exploration and repair. The yoke methodof MT is recommended for this purpose because it is eas-ier to perform and causes no arcing of the magnetizingcurrent at the surface. Hardness tests may be performedusing simple center punch comparators. When hard-nesses are Rockwell 30 or lower, hydrogen-inducedcracking is very unlikely. However, some steels havehigher hardness prior to welding, in which case HAZhardness is limited to the hardness of unaffected basemetal. When the HAZ of the arc strike region has unac-ceptably high hardness, removal of the shallow HAZbelow the arc strike should be performed. Grinding to adepth of 3 mm [1/8 in] below the original surface shouldremove all traces of arc strikes and their HAZs.

C-3.11 Weld Cleaning

C-3.11.1 In-Process Cleaning. Welding should never beattempted through slag or other fused residue from previ-ous weld passes. Attempts to weld through slag and sim-ilar deposits may cause fusion discontinuities. As anexception, plug and slot welding may be done by WPSsthat keep the weld slag molten until the weld is complete.All welding is to be conducted on surfaces satisfying3.2.1. Cleaning by pneumatic or hand chipping hammer,with wire brushing, is usually adequate.

C-3.11.2 Cleaning of Completed Welds. Weld slag,loose or large spatter, and other residue deposits interferewith final weld inspection and may cause coating sys-tems to fail prematurely. All such weld-related residueshould be removed at the completion of welding by thewelder. In reasonable amounts, small tight spatter mayremain unless it interferes with weld testing or painting.Large amounts of weld spatter, even though tight, indi-cate that the weld process may not have been properlycontrolled, and such problems should be investigated andcorrected. Painting should not be done until final weldinspection is complete and the welds and all necessaryrepairs are accepted.


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C-3.12 Weld TerminationC-3.12.1 Because of the mechanism of starting and stop-ping the arc, the termination, start or stop of a grooveweld tends to have more discontinuities than are gener-ally found elsewhere in the weld. Therefore, it is best tostart and end welds on temporary extensions that can belater removed, so that when the temporary extensions areremoved, the start-stop discontinuities are also removed.Weld tabs, also called run-off tabs or extension bars, alsohelp maintain the full cross section of the weld through-out its specified length. Weld tabs are installed in a man-ner that will prevent cracks from forming in the areawhere the weld tab is joined to the member.

When weld tabs are not used, procedures need to producesound welds at any starts and stops on permanent material.

Whenever possible, or whenever it is not impossible orimpractical, weld tabs should be used. Typical exceptionsin bridge construction include stiffener welds, connectionplates and welded gusset plates welded to webs orflanges. In automatic SAW stiffener welding, it is harderto produce a good weld stop than it is to produce a goodweld start. To overcome this problem, many operators ofopposed-head welders start the weld near one flange andthen weld about half of the stiffener length where theytemporarily stop the weld. Welding is then resumed nearthe opposite flange and continued until it intercepts andremelts the initial weld. The welding equipment may beunable to weld to the end of stiffeners, in which case theends are usually finished using another process.

In other arc WPSs, the welder starts the arc and estab-lishes a weld pool of the required size before proceeding.At the stop location, the travel direction is reversed andthe travel speed is temporarily decreased to fill the weldcrater before extinguishing the arc. On automatic equip-ment, this can be accomplished by reversing the traveldirection at the weld end while simultaneously increasingthe travel speed and then shutting off the power.

Extra care should be given to the inspection of all startsand stops for crater cracks.

C-3.12.2 Weld Tabs. Weld tabs are temporary weldextensions. The toughness of the base metal in the weldtab has no effect because they are removed after welding.There is little dilution of the weld metal with the weld tabsteel in the region of the finished weld.

C-3.12.3 The ends of butt joints are to be finished so thatthere will be no discontinuity in the edge of the finishedmember that could concentrate stress and reduce fatiguelife. The width of the weld and part are not to be reducedmore than 3 mm [1/8 in] less than the actual width, or thespecified width, whichever is greater. Reinforcement

remaining above the surface should not exceed 3 mm[1/8 in]. The slope along the edge of the butt joint,where needed, should not exceed 1:10. No surfaceroughness values are applicable.

C-3.13 Weld Backing

C-3.13.1 CJP groove welds made from one side on steelbacking require complete fusion of the weld metal withjoint faces and the backing. Groove welds made withsteel backing have the backing as an integral part of theweld joint. Any discontinuity in the backing perpendicu-lar to significant residual or applied tensile stress maycause the weld to crack at the stress concentration causedby the discontinuity. Only continuous steel backing isallowed by the code, so backing composed of segmentsis joined by CJP welds, and the soundness of those weldsverified, before the backing is installed. A tightly fitted,but unwelded, square butt joint in steel backing consti-tutes a severe notch that potentially leads to transversecracks in the weld that can propagate into the base metal.Once the weld is fused to the backing, the backingbecomes part of the weld and is affected by residual andapplied stress patterns.

C-3.13.2 Steel backing creates stress concentrations inthe root, normal to the axis of the weld. When backing istransverse to applied tensile stress, welds with suchbacking may be subject to fatigue cracking. When back-ing is parallel to applied stress, there is no appreciablereduction in fatigue life. Backing transverse to computedstress requires removal to avoid or reduce stress concen-trations, except in T-joints and columns (see 3.13.2.2).Computed stress, in this application, is both tension andcompression stress. Fatigue cracks can grow in compres-sion members when localized plastic deformations atstress concentrations produce tensile stresses as themember rebounds elastically between cycles of increasedcompression stress. Longitudinal backing is allowed toremain because research has found that it has no adverseeffect on performance. When the contract documentsspecify removal, fused backing is removed, usually byarc gouging and machining, requiring care to avoid dam-aging base metal. Backing can be a site for corrosion. Itis almost impossible to remove longitudinal backingfrom the inside of box members that are not large enoughto accommodate a welder. Removal of longitudinalbacking, if not done properly, may cause discontinuities.

C-3.13.2.1 Steel backing acts as a part of the weld andmay, to a limited extent, influence the chemistry andmechanical properties of the weld. AASHTO M270M[M270] (ASTM A 709M [A 709]) Grade 250 [36] steelbars may be used as backing for almost all welds (see


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3.13.1 for steel backing base metal requirements). Back-ing that is to remain in place is subject to the same mate-rial requirements that apply to the weaker of the partsjoined, except that backing furnished as bar stock and notlarger than 10 mm by 30 mm [3/8 in by 1-1/4 in] neednot conform to the toughness requirements of the specifi-cations. Toughness is not specified for backing because,unless large in cross section, it will not affect the fracturesafety of the member. Also, the heat from welding sub-stantially changes the mechanical properties of thesesmall bars, invalidating any previous CVN values.

C-3.13.2.2 When backing is in a T-joint and is subjectonly to compressive stresses, such as a column that car-ries only compressive loads, it may remain in placeunless otherwise specified by the Engineer. Backing inbutt and corner joints, except in compression areas, is tobe removed in conformance with 3.13.2.

C-3.13.2.3 When the backing bar is attached to thesteel with external welds, or welds not within the com-pleted welded joint, the weld attaching the backing bar ismade continuous full length and meets all requirementsof the code. Intermittent welds would serve as fatiguefracture initiation sites and are prohibited for this purpose.

C-3.13.4 These thicknesses are considered the minimumthickness to avoid burn-through for the given process.This assumes that the joint and the backing are assembledcorrectly. Smaller thicknesses may be used for the pro-

cesses shown when small electrodes or other factorsallow the welding process to be operated with a mid-range heat input. Low heat input welds are not desirableand should not be used to facilitate the use of thinbacking.

C-3.13.5 If backing does not fit tightly for the full lengthof the joint, it is difficult to produce sound welds andmuch more difficult to perform accurate UT. Loose weldbacking escalates repair welding and testing costs. Becauseof flux and weld metal leakage at the interface of thebase metal and a poorly fitting backing bar, porosity andslag may occur with subsequent failure to pass NDTquality criteria.

C-3.13.6 It may be necessary to make root passes fromthe outside of box members and columns that do notallow access to the back of the weld. For this reason,alternative materials to steel backing are allowed. Anybacking material proposed, except steel backing or weldmetal deposited by code-approved SMAW electrodes oran approved low-hydrogen WPS, is to be qualified bytest in conformance with the provisions of 5.7. A highlyskilled welder with proper training is necessary whenusing nonsteel backing. Copper backing is not permittedif it may be contacted by the welding arc and melted intothe weld pool, because copper in the weld or HAZ cancause severe cracking. Note that qualification of water-cooled copper shoes may be considered if the possibilityof copper melting is avoided.


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Figure C-3.1—Examples of Unacceptable Reentrant Corners

Figure C-3.2—Examples of Good Practice for Cutting Copes


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Figure C-3.3—Permissible Offset in Abutting Members (see 3.3.3)

Figure C-3.4—Correction of Misaligned Members (see 3.3.3)


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Figure C-3.5—Illustration of Camber Tolerances for Steel Beams


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Figure C-3.6—Measurement of Flange Warpage and Tilt (see C-3.5.1.7)


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Figure C-3.7—Tolerances Bearing Points (see C-3.5.1.9)



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C-4.1 Filler Metal Requirements. Users are encour-aged to adopt electrode specifications and classificationsas these become available.

C-4.1.1 Undermatching weld metal utilizes electrodesthat are shown in Table 4.1 or 4.2, even though they willnot be used with the steels they are listed with. Matchingweld metal strength uses filler metals for the specificgrade of steels shown on Table 4.1 or 4.2.

C-4.1.2.1 Based on research conducted on HPS 485W[HPS 70W] by the High Performance Steel SteeringCommittee and Welding Advisory Group under a coop-erative agreement sponsored by the Federal HighwayAdministration (FHWA), the U.S. Navy, and the Ameri-can Iron and Steel Institute (AISI), a maximum diffusiblehydrogen content of 8 mL/100 g and the preheat andinterpass temperature requirements of Table 4.4 wereadequate to produce crack resistant weld deposits. Adiffusible hydrogen content greater than 8 mL/100 gwith various heat inputs produced varying results whichpossibly could affect the weld quality of these higherstrength materials, although not necessarily limited to HPSmaterial.

Therefore, the consensus of the HPS Welding AdvisoryGroup was to propose a requirement for a maximumdiffusible hydrogen content of the welding consumablesto be 8 mL/100 g for use with conventional, nonfracturecritical components to avoid the potential for cracking ofthese high strength materials when using the existingpreheat requirements of Table 4.4 of this code.

C-4.2.1.2 Based on research conducted on HPS 485W[HPS 70W] by the High Performance Steel SteeringCommittee and Welding Advisory Group under a coop-erative agreement sponsored by the Federal HighwayAdministration (FHWA), the U.S. Navy, and the Ameri-can Iron and Steel Institute (AISI), lower preheat andinterpass temperatures could be allowed by controllingthe filler metal diffusible hydrogen content and mini-

mum and maximum heat inputs. AASHTO adopted theserequirements in both the first and second editions of theGuide Specifications for Highway Bridge Fabricationwith HPS 70W Steel, which has been used as a guide tofabricate and weld numerous bridges in service for sev-eral years. These optional requirements and controls arein Annex H.

C-4.5.2.3 Optional Supplement Moisture-ResistantDesignators. In order for a low-hydrogen electrode to bedesignated as low-moisture-absorbing with the “R” suf-fix designator, electrodes are tested by exposure to 27°C[80°F] and 80% relative humidity for a period of not lessthan 9 hours. These tests are defined in AWSA5.1/A5.1M and A5.5/A5.5M, and are conducted by theelectrode manufacturer. The nine hour time period wasselected based upon a typical workshift length, includingmealtime. The moisture content of the exposed coveringmay not exceed the maximum specified moisture contentfor the “R” designated electrode and classification in theappropriate A5.1/A5.1M or A5.5/A5.5M specification.Such electrodes may be used with exposure times of upto nine hours on steels with a minimum specified yieldstrength of 345 MPa [50 ksi]. For higher strength steels,exposure time is limited to that described in Table 4.7.

C-4.8.3 When flux is exposed to the open atmosphere,the flux may adsorb moisture. When welding operationsare not resumed within 24 hours, flux that has been opento the atmosphere is required to be replaced. During theweek of a single shift operation, the flux in open hopperscould be left exposed. However, if the welding equip-ment is not used for one day, such as is the case over astandard weekend, the flux is replaced before weldingoperations resume.

Closed systems have engineered enclosures that effec-tively restrict the exchange of air within and without thesystem. Closed flux delivery systems, such as pressur-ized tanks and some vacuum recovery systems, provide

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additional protection from the atmosphere. Flux in thesesystems is allowed to remain when welding is suspendedfor up to 96 hours. This allows the Contractor to leaveflux in such systems over three day weekends, or otherthree day periods where production may be interruptedfor other reasons.

The 24-hour and 96-hour rules were established to pre-vent continuation of welding with existing flux aftermajor shutdowns.

If flux comes in direct contact with water, it is to be dis-carded. It may not be dried and subsequently used.


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Introduction

C-5.0 Scope

Two types of qualification tests are described in thisclause: Welding Procedure Specification (WPS) Qualifi-cation Testing as contained in Part A, and QualificationTesting of Welding Personnel as contained in Part B.

Qualification of WPSs is required by this code to demon-strate that welds of the required soundness and mechani-cal properties can be achieved.

The strength, ductility and toughness of the depositedweld metal depend on the (a) weld metal chemistry, (b)cooling rates experienced by the weld metal, and (c) sub-sequent heating (if any) of the deposit. Similarly, theproperties of the HAZ are influenced by the same factorsexcept that the chemistry involved is that of the basemetal that is not changed by welding.

The weld metal chemistry is dependent upon the chemis-try of the filler metal and the base metal composition.Most of the composition of the weld metal is provided bythe electrode and, where applicable, flux. A portioncomes from the base metal, including fused backing.Welding variables may affect the weld chemistry. Higheramperages are associated with deeper penetration,which, in turn, introduces more of the base metal into theweld pool. Alternately, low amperage WPSs will havewelds that are more dependent upon the filler metalcomposition.

The cooling rate associated with a weld deposit and theHAZ are dependent upon many factors. Slow coolingrates are encouraged with higher levels of preheat andinterpass temperature, higher heat input levels, and thin-ner plate thicknesses. Conversely, high cooling rates areassociated with low preheat and interpass temperatures,thicker plates, and low heat input levels.

High cooling rates generally result in weld metal andHAZs that are higher in strength, lower in ductility, andlower in toughness. Slow cooling rates are associatedwith lower strength welds and HAZs, greater ductility,but also lower toughness. The optimum balance ofstrength, ductility, and toughness is achieved when cool-ing rates are properly positioned between these twoextremes.

The toughness of a weld deposit is particularly sensitiveto welding parameters, and cooling rates that are eithertoo rapid or too slow may negatively affect toughness.Rapid cooling rates result in acicular grain structures thatare typically lower in toughness. Slow cooling ratesresult in very large grains which are also low in tough-ness. Optimum cooling rates result in an equiaxed grainstructure, with optimal toughness.

High cooling rates minimize the time for hydrogen diffu-sion while slower rates maximize the opportunity forhydrogen to migrate out of the weld and HAZ.

Balance is therefore required in order to maintain anappropriate level of strength, ductility, toughness, anddiffusion of hydrogen.

Multiple pass welds subject previous weld passes toadditional thermal cycles, reheating portions of the pre-viously deposited weld, generally resulting in improvednotch toughness. This also results in a reheating of theHAZ and changes in that region as well. Single-passwelds are not subject to this generally beneficial reheat-ing of the weld.

The WPS qualification tests imposed by this code are notdesigned to measure the resistance of a weld metal orbase metal to hydrogen-induced cracking. The lowrestraint associated with these test plates makes itunlikely that this type of cracking would be detectedexcept under the most extreme conditions.

Weld soundness depends on the proper combination ofwelding variables (amperage, voltage, travel speed, etc.)in combination with the joint of the proper geometry

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(root angle, root opening, etc.). When standard weldingjoints as illustrated in Figures 2.4 and 2.5 are used, nospecific tests of the joint detail are required since thesejoint details have a long history of satisfactory perfor-mance. When details differ from these joints, specifictests are required to determine the suitability of the com-bination of welding variables to the particular jointdetail.

There is no practical method to measure fillet weld prop-erties, particularly for small, single-pass welds. Whileacknowledging that there may be significant differencesbetween the properties of these welds and groove welds,the code nevertheless requires that fillet weld WPSs bequalified by testing weld metal deposited in groovewelds and by performing soundness tests. Fillet weldsare typically loaded in shear and therefore not loaded sig-nificantly, and the required toughness of such welds isunknown. As a result, there is no requirement to quantifyby test actual fillet weld properties.

The code requires simple tests that can verify the skilllevel of the welding personnel who will be performingthe welding. Even with a good WPS, poor technique orsetup skills may create discontinuities that may initiatefatigue cracking. Welding personnel qualification testingis as described in Part B.

Part AWelding Procedure Specification

(WPS) Qualification

C-5.1.1 Purpose of WPS Qualification Tests. Theseprovide assurance that the production welding to be per-formed will provide the strength, ductility and toughnessrequired by the design. AWS D1.1, Structural WeldingCode—Steel, allows WPSs to be prequalified, exemptfrom WPS qualification testing, when in conformance tospecific requirements. Because toughness is importantfor bridge performance, and because weld toughness isdependent upon not only the filler metal used, but also thecombination of welding parameters employed, WPS qual-ification testing is generally required by D1.5.

Tests to classify welding consumables, including elec-trodes and electrodes used in combination with fluxes orshielding gas, are described in the AWS A5.XX FillerMetal Specification series. These test WPSs are notintended to duplicate all production welding conditionsor WPSs. The WPSs followed by the manufacturer ortesting firm for filler metal classification testing are veryspecific and uniform, done under the specified test con-

ditions, so that the results of common tests can becompared.

There may be a substantial difference between themechanical properties of welds made by welding con-sumable classification tests and the strength, ductility,and toughness measured when test specimens are madefrom actual production welds.

As an example, applicable specifically to SAW, electrodesand fluxes are produced under the provisions of AWSA5.17/A5.17M or A5.23/A5.23M, for carbon steel elec-trodes and low alloy steel electrodes, respectively. Carbonsteel electrodes and fluxes are tested by welding at28 volts. Alloy steel electrodes and fluxes are tested bywelding at 26 volts to 32 volts, depending upon the elec-trode diameter. Typically, fifteen weld passes are depos-ited in seven weld layers on the 25 mm [1 in] test plate.However, production welding may routinely use highervoltages, affecting the amount of flux melted. This, inturn, can affect the weld chemistry, especially when activefluxes and alloy fluxes are used (see C-4.8 for a descrip-tion of SAW electrodes and fluxes). Mechanical propertiessuch as strength, ductility and toughness may be affected.

One method for ensuring that production weld metalproperties created by a particular WPS meet all the coderequirements would be to test each individual WPS,allowing no variation in welding parameters. In additionto requiring requalification for all changes in weldingconsumables and WPS variables, retesting would also berequired for significant changes in base metal thick-nesses and for each grade of steel to be welded. How-ever, it would be impractical and unwarranted to testevery set of conditions that would be used in production.Tests that allow a broader range of WPS variables areused to keep the required number of WPS qualificationtests to a minimum.

Weld metal produced by welding in conformance withthe provisions of WPSs proposed by the Contractorshould produce mechanical properties that conform tothe requirements of Table 4.1 or 4.2, as appropriate.Because filler metal classification tests may be con-ducted under different welding conditions, the weld metalproduced by D1.5 qualification tests are not required tosatisfy the same requirements as the applicable AWSfiller metal specification.

Consistent weld soundness and mechanical propertiesrequires adherence in production to a good WPS. Thetesting procedures described in the code evaluate thesuitability of essential variables based upon differencesin calculated heat input. In addition to specifying qualifi-cation testing procedures, the code also specifies meth-ods for the control of welding variables in production.Little assurance of actual weld performance would be


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offered if welding parameters were allowed to vary sig-nificantly from the values tested. The adjustment of volt-age, current and travel speed allowed in Table 5.3 couldallow the welding heat input to vary such that maximumwelding heat input could be twice the minimum weldingheat input. That may not be acceptable for bridge con-struction, where toughness is critical to safety, unlesstests are used to verify that the specified minimumtoughness will be produced. The WPS qualification testsdescribed in this subclause, together with the proceduresfor control of welding variables described in Clause 4,Part G, provide confidence that production welds willachieve the mechanical properties required by the codeor contract documents.

The mechanical properties described in Tables 4.1 and4.2 for qualification, pretest, or verification testing aresuitable for bridge construction. The Engineer mayaccept other values using engineering judgment. Thenotes to Tables 4.1 and 4.2, particularly Note 6, provideguidance regarding the justification and approval ofalternate test results.

In addition to providing for the qualification and controlof WPSs based upon the maximum welding heat input,provisions are also made for maximum/minimum “enve-lope” heat input testing and control. This qualificationoption was developed to provide assurance of goodmechanical properties, while using a minimal number ofqualification tests, to evaluate the extremes in weldingheat input.

C-5.2 Qualification Responsibility

The Contractor is responsible for all qualification andverification testing, demonstrating that the Contractorcan produce the results described by the code. The Con-tractor cannot delegate responsibility for qualificationtesting to a third party. When a choice between qualifica-tion methods is provided, the Contractor may select theoption that best suits the situation.

C-5.2.2 Contractor. It is the Contractor’s responsibilityto perform the WPS qualification tests required by thecode. Written WPSs are then produced for use in produc-tion welding.

C-5.2.3 Engineer. Properly documented WPS qualifica-tion tests, conducted by the Contractor in conformancewith this code, are to be approved by the Engineer. Theacceptability of qualification using other standards is atthe Engineer’s discretion, to be exercised based upon thestandards used, the structure, and service conditions.

The Engineer is encouraged to accept evidence of priorqualification, provided the tests were properly conductedand witnessed within the past 60 months. This provision isintended to encourage reciprocity between Owners(States), avoiding unnecessary cost and duplication ofeffort.

C-5.2.4 Excess Testing. Tests in excess of thoserequired by the code are considered extra work subject topayment by the Owner. When extra tests are necessary,the Owner may include extra testing requirements in thecontract by listing the required tests in the contract docu-ments prior to bidding. When this is done, the Contractoris informed of the extra testing in advance and caninclude the cost in the bid. Additional testing is not rou-tinely justified because the code testing requirements aregenerally adequate for the bridge structures covered bythe code.

The Engineer may order appropriate requalification testswhenever WPSs produce unacceptable results.

C-5.2.5 Records. PQRs and WPSs should be availablefor review by the Inspector, Engineer, or Owner.

C-5.3 DurationWPS qualification tests need to be completed, witnessed,and reported on the PQR within 60 months of the startingdate of welding on that particular project. Once a projecthas begun, it would be unnecessary to repeat qualificationtesting simply because the 60-month period since testinghas elapsed. For another project beginning productionwelding after the 60-month period has elapsed, retestingwould be necessary.

C-5.4.1 Base-Metal Qualification Requirements. Thechemical composition of the steel used as test plates andsteel backing can affect test results. Chemical elementsobtained by pickup, also called dilution, from the basemetal can affect hardness, strength, ductility, andtoughness.

In qualification testing using approved steels with a min-imum specified yield strength of 345 MPa [50 ksi] orless, a more hardenable steel may be substituted for aless hardenable steel in the same series. This is done toavoid unnecessary qualification testing. A WPS thatworks well on Grade 345W [50W] steel of the specifiedminimum composition should also work well whenwelding lower strength steels.

When substitution of steel grade is based upon estimates ofhardenability, a conservative approach requires that the testplates be at least as hardenable as the steel to be welded.This is accomplished when Grade 345W [50W] steel of


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the chemistry described in 5.4.2 is substituted for steelswith a minimum specified yield strength of 345 MPa[50 ksi] or less. Grade 345W [50W] is generally morehardenable than Grade 250 [36], Grade 345 [50], orGrade HPS 345W [HPS 50W] steel. Grade 345 [50] steelis generally more hardenable than Grade 250 [36] steel.

This same rule does not apply to approved steels with aminimum specified yield strength greater than 345 MPa[50 ksi]. Where higher strength and higher hardenabilityare involved, a more conservative approach is used. Thesteel to be welded in production is represented in theWPS qualification test by steel of the same nominal spec-ification chemistry, therefore the test plate and backingneeds to be of the same specification and grade. Manysteels conforming to a specific AASHTO/ASTM desig-nation are manufactured in several grades, each with adifferent chemistry. Testing of WPSs that join highstrength steels is done using the actual steel specificationand grade that is to be welded in construction.

The standard tests required by the code for WPS qualifi-cation testing do not evaluate base metal, or HAZ CVNtest values, and therefore, the base metal for WPS quali-fication testing is not required to have minimum speci-fied CVN test values. Having such CVN test values isdesirable, but not required. The lack of specified CVNtest values may negatively affect some test results, par-ticularly if HAZ CVN testing has been specified in con-tract documents.

C-5.4.2 Grade 345W [50W] Test Plate ChemistryRequirements. Three options are provided to ensure thatthe AASHTO M270M [M270] (ASTM A 709M [A 709])Grade 345W [50W] steel, used to represent either Grade250 [36], Grade 345 [50], HPS 345W [HPS 50W], orGrade 345W [50W] steel, is at least as hardenable as thesteel reasonably anticipated to be used in bridges. If nolimits were placed on chemistry, some steels of thesegrades could be more hardenable and therefore moredifficult to weld than a “lean chemistry” Grade 345W[50W] steel used in the test.

This is particularly true when heavy sections are to bewelded. The chemical composition of steel is allowed tovary within limits established by the steel specifications.Heavy sections generally have more hardenable chemis-tries than thin sections to ensure that the requiredstrength is produced. This is necessary because of slowercooling rates and less mechanical working during rollingat the mill.

If the Grade 345W [50W] test plate and backing steel hasat least the minimum specified percentage of carbon,manganese, silicon, chromium and vanadium describedin this subclause, it will have a hardenability that is equalto or greater than any Grade 250 [36], Grade 345 [50],

HPS 345W [HPS 50W], or Grade 345W [50W] steellikely to be used in bridge construction.

The Contractor should carefully evaluate whether thisunique test plate composition will be advantageous forthe situations involved. For example, a WPS that wouldbe used only with Grade 345 [50] and Grade 250 [36]steels would not require the use of the alloy electrodesdescribed in Table 4.3 for weathering applications. Qual-ification using Grade 345 [50] steel allows use on Grade250 [36] steel (see 5.4.1). For this situation, the specialGrade 345W [50W] steel is not necessary.

Because Grade 345W [50W] steel conforming to theabove chemistry requirements has been difficult toobtain in some cases, and therefore is seldom used, twoadditional methods of ensuring adequate hardenabilityare provided.

The first method utilizes a Carbon Equivalent (CE) equa-tion. The CE equation estimates hardenability by listingthe elements that have the greatest affect on hardening.CE equations compare the relative hardenability of dif-ferent steels based upon the hardening produced by thetotal amount of carbon and carbon “equivalents” in theircomposition. The carbon equivalent is the sum of thefractions obtained by dividing the various chemical ele-ments by a number that estimates how much hardeningthat element produces compared to an equal amountof carbon. Carbon produces hardness more efficientlythan any other element and therefore is used as the stan-dard of comparison. Numerous CE equations have beenpublished. They are considered estimates, and varydramatically. Some are more effective for specific com-positions than others. The code presents one option for aCE equation.

The chemical requirements for the test plate material isnot a requirement for the production steel to be used in thebridge. The goal of this provision is to mandate qualifica-tion testing on a poorer weldability steel to ensure accept-able results for the range of steels that could be deliveredunder current AASHTO⁄ASTM steel specifications.

The second method of ensuring adequate hardenabilityrequires computation or experimental measurement ofthe ideal critical diameter. The computation or measure-ment of the ideal critical diameter may be more accuratebecause it considers all elements in the steel composi-tion. Calculation of the ideal critical diameter requiresknowledge of the metallurgical effect of each element inthe chemical composition. Measurement of the ideal crit-ical diameter may be done using quench tests or analyti-cally computed based upon empirical relationships.Physical Metallurgy for Engineers by Clark and Varney,Second Edition, D. Van Norstrand Company, New York;and The Making Shaping and Treating of Steel, Tenth


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Edition, by The Association of Iron and Steel Engineers,Pittsburgh, PA.; and by Republic Alloy Steel, Cleveland,Ohio, may be consulted for further information.

C-5.4.3 Use of Unlisted Base Metals. The Engineermay approve the use of steels not listed in AASHTOM270M [M270] (ASTM A 709 [A 709M]), based uponadequate documentation for the steel that is proposed,and appropriate testing to verify mechanical propertiesand weldability if not known. The effect of heat inputand cooling rates on the mechanical properties of thesteel, weld, and HAZ may be determined by testing asdescribed in 5.13.

C-5.4.3.1 The contract documents may also requireCVN testing of the HAZ. CVN testing of the HAZ israrely done for WPS qualification for bridge applica-tions. Therefore, when the contract documents requireHAZ toughness testing, detailed instructions should beprovided for the testing procedure.

CVN testing of the HAZ can determine if the propertiesof the base metal have been affected by the heat gener-ated from welding. Quenched and tempered steelsachieve their high strength and good toughness, in largepart, to fine grain produced by the heat treatment. Highwelding heat inputs that subject the HAZ to high temper-atures for long periods may cause the HAZ grains nearthe fusion line to grow, or coarsen. Grain coarseninggenerally reduces toughness. The most serious degrada-tion in toughness occurs within 2 mm [1/16 in] of thefusion line. Details of testing should specify the CVNtest specimen notch location and provide other details sothat the fracture will sample the weakest part of theHAZ. Precise location of the CVN notch in the coarsegrained area requires a high degree of metallographicskill and is extremely difficult under the best of conditions.

C-5.4.5 WPS Backing. The chemistry of the backing isimportant because it may affect, by pickup, the chemistryof the weld metal. Toughness of the backing has noeffect upon the test results and need not be specified ortested.

C-5.4.6 The actual combination of base metal and fillermetal that will be used in production are used for thePQR.

C-5.5 Welding ConsumablesAll welding electrodes, fluxes and shielding gasesdescribed in Tables 4.1 and 4.2 conform to the require-ments of the AWS Filler Metal Specification seriesA5.XX, and are regularly tested by the manufacturer orother party as required by those specifications.

Only low hydrogen welding electrodes may be used underthe provisions of this code. Table 4.1 is restricted toSMAW with a minimum specified yield strength of lessthan 620 MPa [90 ksi], SAW, and FCAW-G (with exter-nal gas shielding), in the strength levels specified. Theannual testing requirement is for the classification testsconducted by the manufacturer or other party to verify thatthe consumables conform to the procurement specifications.

C-5.5.1 WPS Requirements for Consumables. Eachbare solid wire electrode, based upon chemical classifi-cation (but not each manufacturer’s brand), each shield-ing gas or gas mixture, and each manufacturer’s brandand type of flux or FCAW electrode, is qualified by thetests described in this subclause. The code accepts theAWS classification of bare (not coated with flux), solid,steel welding electrodes on the basis of chemical compo-sition. Solid steel electrodes are accepted by the codewithout regard to the manufacturer’s name or brand.Fluxes and FCAW electrodes are considered individualproducts based upon manufacturer’s brand and type,regardless of AWS filler metal classification. Operatingcharacteristics of these types of products may varybetween manufacturers, even though generically classi-fied the same.

Pure, single element shielding gases and accurate mix-tures of shielding gases may be considered generic andare not subject to requalification due to a change in thegas producer. Gases used to shield FCAW, GMAW, orEGW are usually a single gas or a proportioned gas mix-ture, e.g., 75% CO2 and 25% Ar. To minimize qualifica-tion testing for minor changes in the total mixture, Table5.1, Note 2 does not require requalification unless achange in the minor element exceeds 25%. A 25% changeof a 20% minor element is only a 5% change in the totalmixture.

C-5.5.2 Active Flux. Active fluxes are those which con-tain small amounts of manganese, silicon, or both. Thesedeoxidizers are added to the flux to provide improvedresistance to porosity and weld cracking caused by con-taminants on or in the base metal. The primary use foractive fluxes is to make single-pass welds, especially onoxidized base metal. Since active fluxes do contain somedeoxidizers, the manganese, silicon, or both in the weldmetal will vary with changes in arc voltage. An increasein the manganese or silicon increases the strength of theweld metal in multiple pass welds. For this reason, volt-age is more tightly controlled for multipass welding withactive fluxes than when using neutral fluxes.

Neutral fluxes, in contrast, are those which will not pro-duce any significant change in weld metal chemical anal-ysis as a result of a large change in the arc voltage, andthus, the arc length. The primary purpose for neutral


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fluxes is in multiple pass welding, especially when thebase metal exceeds 25 mm [1 in] in thickness. Since neu-tral fluxes contain little or no deoxidizers, they rely onthe electrode to provide deoxidization. Single-pass weldswith insufficient deoxidization on heavily oxidized basemetal may be prone to porosity, centerline cracking orboth.

While neutral fluxes do maintain the chemical composi-tion of the weld metal even when the voltage changes, itis not always true that the chemical composition of theweld metal is the same as the chemical composition ofthe electrode used.

A third type of flux is alloy flux that is distinctly differ-ent than either active or neutral flux. Alloy fluxes arethose which can be used with a carbon steel electrode tomake alloy weld metal. The alloys for the weld metal areadded as ingredients in the flux. They are commonly usedfor welding weathering steels.

The code restricts the use of active fluxes to single andtwo pass applications, unless there is specific qualificationunder 5.13 and approval by the Engineer. For these lim-ited pass applications, the extra level of deoxidizers makethe flux the preferred choice of many Contractors. How-ever, when extended to welds of 3 passes or more, prob-lems may be encountered as the alloys of silicon andmanganese can accumulate and contribute to cracking. Touse active fluxes for large multipass welds, electrodes oflow carbon, low silicon and low manganese content (typi-cally EL12) are used, and voltage needs to be carefullycontrolled.

Active fluxes are generally not used to make large multi-pass welds. The amount of alloy picked up from the fluxis influenced primarily by the arc voltage. The 25 mm[1 in] test plate is considered adequate for this testbecause of the code’s limitation on active fluxes to oneand two-pass welds, unless approved by the Engineer.

C-5.6 Test Plate ThicknessPrevious editions of the code have required WPS qualifi-cation on two thicknesses of steel, depending on thethickness of the material to be joined in production. Thisqualification requirement was based upon an assumptionthat differences in cooling rates would result in differ-ences in mechanical properties such as yield and tensilestrength, ductility, and toughness. The thicker plateswere expected to generate higher cooling rates, resultingin higher strength levels and lower ductility values. Thinplates were expected to have just the opposite affect onstrength and ductility, and also expected to result in lowertoughness values.

WPSs have been qualified by this method since theBridge Code was first issued in 1988, and two differentplate thicknesses were used in the 1978 AASHTO Frac-ture Control Plan. The data from these tests were used tobuild a table that allowed for comparison of actual valuesobtained from essentially identical WPSs, but performedwith different plate thicknesses. The changes in yield andtensile strength, while generally predictable, were negli-gible. Acceptable ductility values were obtained in allcases. The average yield strength for the slower-coolingthinner-plate specimens was 94% of the thicker-platevalues. The average tensile strength of specimens fromthe thinner plates was 99% of that associated with thethicker plate.

With nominally identical WPSs, and test plate thicknessas the only variable, CVN test values were affected to agreater extent than the tensile strength and elongationvalues, but no uniform trend was seen. In some cases,higher values were obtained for the CVN values undertest conditions that involved thick plates while in othersituations, the thinner plates had better values. This wasdeemed to be due to other variables than the cooling rate.

Frank and Abel evaluated several hundred PQRs andfound that plate thickness, as well as a variety of otheressential variables described in the code, did not serve asa good predictor of the probable mechanical properties.Further work done by Medlock and Frank further identi-fied the lack of actual trends for these essential variables,despite the fact that some theoretical basis exists suggest-ing they are important.

After analyzing this data, and after considering the eco-nomic implications of continuing to mandate two platethicknesses be used to qualify the full range of thick-nesses that could be used in production, the Committeedecided to standardize all WPS testing on one platethickness. In doing so, some confusion that existedregarding the required plate thickness for certain applica-tions was eliminated.

Although the code does not require that WPS qualifica-tion be performed on the actual thickness of steel thatwould be used in production, differences between thethicknesses of steel in production and that qualified bytest do affect properties. Thicker steel will result inhigher cooling rates, all other factors being equal. How-ever, the code mandates higher levels of preheat withthicker steels. Applications involving thick sections aremore highly restrained, although it has never been rec-ommended that the qualification test plates duplicate therestraint that would be seen in actual applications.

C-5.7.1 WPS Qualification Test. WPS qualificationtesting is performed to verify that the WPS will produceweld metal with at least the specified soundness,


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strength, ductility, and toughness. The test evaluates themechanical properties of the weld metal produced bywelding under conditions that are generally representa-tive of production welding. Testing is done by the Con-tractor using Test Plate A, Figure 5.1. The WPSqualification test is welded by the Contractor. No otheragency may conduct the test for the Contractor. The testdoes not evaluate the details of the welded joint itself.Once the WPS is qualified by test, it may be used with-out further testing on those joints detailed in Figures 2.4and 2.5.

The Procedure Qualification Record (PQR) is the writtendocument stating the actual welding variables used toproduce the WPS Qualification Test weld, and also stat-ing the test results.

In Figure 5.1, control of the direction of rolling isoptional, although the mechanical properties, especiallyductility, of the steel plate may vary significantly withthe direction of rolling and may affect the test results.Unless cross rolling is used, tensile strength and impacttoughness are often greater in the rolling direction than inthe transverse direction. Using the rolling directionshown often gives better results in bend tests.

C-5.7.2 Pretest. The WPS pretest is identical to the WPSqualification test described in 5.7.1, except that the test isperformed by someone other than the Contractor, and thetest is only performed under the provisions of 5.12 toestablish limits on welding heat input.

Pretests may be performed by filler metal manufacturers,testing laboratories, and other qualified groups or indi-viduals, to establish the effectiveness of proposed WPSs.They may only be used for the processes and filler metalsdescribed in Table 4.1. When a Contractor establishesthe WPSs on acceptable pretest PQRs, only the lesscostly verification test need be conducted.

C-5.7.3 Verification of Pretest PQRs. The WPS verifi-cation test described using Test Plate B, Figure 5.2, is asimplified and less expensive form of mechanical test-ing. Verification tests are only performed when the Con-tractor has used pretests (WPS qualification testsconducted by others) as a basis for writing the WPS.Verification tests verify that the Contractor can producethe required results when following a WPS based upon aPQR provided by another party. Acceptable WPS pre-tests need to be less than 60 months old, for consider-ation of verification testing.

C-5.7.4 Table 4.1 Processes. All welding processesapproved for use by the code have been used success-fully for many years. Table 4.1 welding processes have alonger history of successful use than Table 4.2 processes,and are considered by the Committee to be more tolerant

of changes in process variables without adversely affect-ing weld soundness or required mechanical properties.Table 4.1 processes are sufficiently tolerant of changesin WPS variables to allow the option of verification test-ing by the Contractor.

C-5.7.4.1 Consumables. Welding consumablesdescribed in Table 4.1 are more tolerant of changes inwelding variables than the consumables described inTable 4.2. Bridge Owners also have more experiencewith these consumables. The Contractor may qualify aWPS using either 5.12 or 5.13, or may obtain a pretestedprocedure from another source and perform the lessexpensive verification test.

When WPS qualification testing is required, the Contrac-tor performs the testing.

C-5.7.5 Table 4.2 Processes. Welding consumablesdescribed in Table 4.2 are either those that produce veryhigh strength weld metal or require a higher level of careto produce sound welds with the specified mechanicalproperties.

The placement of a welding process in Table 4.2 doesnot indicate that the process is inherently less suitablethan another. GMAW WPSs and FCAW-S WPSsmay require closer control of welding variables andtechniques to produce sound welds with the specifiedproperties, compared to SAW, SMAW, and FCAW-Gprocesses. Joints welded using ESW and EGW requirefull WPS qualification tests by the Contractor for thesame reason.

C-5.7.7 Joints Not Conforming to Figure 2.4 or 2.5.Contractors are encouraged to use joint details that mini-mize shrinkage, distortion, and residual stress, especiallywhen shrinkage stresses to members in the transverse“Z” direction may cause lamellar tearing. This may bedone by redesigning the joint to reduce the required weldvolume. The joint details described in Clause 2 are suit-able for most routine welding applications, but may beimproved upon when necessary, especially for largegroove welds in heavy sections.

The root opening and the included angle of groove weldsshould be as small as possible, yet provide adequateaccess to achieve sound fusion when welded (see C-2.1.2and C-3.4). Test Plate C, Figure 5.3, is designed to evalu-ate weld soundness, with the required mechanical prop-erties, when following an approved WPS to weldproposed nonstandard joint details.

When welding is performed following a given WPS,changes in the joint geometry require changes in thenumber of weld passes in proportion to the difference inweld volume. Because of the groove angles used, weldvolume increases at a rate higher than the rate of weld


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thickness increase. Changes in the same joint detail donot require requalification of the WPS if the only WPSchange is to fill more or less volume.

The bend and tensile tests specified verify that goodfusion has been achieved between the weld metal and thebase metal and between the weld metal and any previ-ously deposited weld passes.

C-5.7.8 Aging. “Aging” or “artificial aging” consists ofa post-weld thermal treatment whereby the test speci-mens are allowed to be heated to temperatures of 95°C–105°C [200°F–220°F] for up to 48 hours before mechan-ical testing. Aging involves the release of hydrogen afterwelding has been completed.

Artificial aging of qualification test welds or weld testspecimens is specifically prohibited by the code, unlessthe production bridge welds represented by the testingare required to receive the same treatment. Hydrogen dif-fuses from welds and HAZs into the atmosphere overtime. Small specimens with short travel distances forhydrogen to escape require a relatively short time periodfor hydrogen to release. Considering the time required tomachine test specimens and prepare them for testing, aspecimen that fails testing as a result of hydrogen maydemonstrate that the WPS is not suitable for bridgeconstruction.

Deliberately delaying testing to naturally age test speci-mens at room temperature, although not prohibited,should not be necessary to pass standard WPS tests.

C-5.7.10 It is not the intent of this code to require allqualification tests to be redone every time a new editionis issued.

C-5.7.11 Qualification of undermatching weld metal willbe done with the undermatching filler metal and thehigher strength base metal to be used in production.

C-Figure 5.1. In the previous editions of the code, a spe-cific joint geometry accompanied Figure 5.1, requiringthe use of a root opening and included angle that wasstandard for only SAW welding. This yielded a varietyof problems in qualification testing, particularly for out-of-position welding and gas-shielded semiautomatic pro-cesses. Figure 5.1 was changed to allow the use of alter-nate joint details that would be standard for the positionof welding, and the welding process. Certain joint detailswere precluded because the combination of the rootopening and the included angle for the specific thicknessof test plate required precluded the extraction of an all-weld metal coupon from only weld metal.

C-Figure 5.2. See commentary for Figure 5.1.

C-5.8.1 Qualification Requirements. All WPSs arequalified for the position(s) in which they will be oper-

ated. Different welding positions may require differentwelding parameters, techniques, electrodes, and in somecases, equipment. Most high heat input WPSs are suit-able for welding only in the flat and horizontal weldingpositions, although high heat is also used when weldingvertical up. Changes in welding position have a majoreffect upon welding travel speed and current. The result-ing heat input and cooling rates are changed dramati-cally, significantly affecting the mechanical properties ofthe weld and HAZ.

C-5.8.2 Groove Weld Test Positions. An exception ismade to allow test welds made in the flat position to alsobe considered for qualification of the horizontal position.This exception is allowed for groove weld positions andmay also be considered to qualify fillet weld WPSs. Thisexception, however, does not extend to the fillet weldsoundness test (see 5.10.3).

C-5.8.2.2 Position 2G (Horizontal). WPS qualifica-tion tests performed in the flat position also serve asqualification for horizontal. Most fillet welds are made inthe horizontal position, and the WPS qualification usinga groove weld is applicable to qualify flat and horizontalfillet welds.

C-5.8.2.3 Position 3G (Vertical). Typical vertical-down WPSs may produce the least amount of weldingheat input. Vertical-down WPSs are qualified by testingapproved by the Engineer (see 4.6.8 for SMAW and4.14.1.7 for GMAW and FCAW).

C-5.9 Options for WPS Qualification or Prequalification

Groove weld WPS qualification testing for standardgroove weld joint details as shown in Figures 2.4 and 2.5may be performed using the Production Procedure WPStest of 5.13. For these joints, welded using FCAW-Gor SAW with filler metals described in Table 4.1, theMaximum Heat Input test of 5.12.1 or the Maximum-Minimum Heat Input test of 5.12.2 may also be used. Forthese joints welded using SMAW with filler metalsdescribed in Table 4.1 (yield strength less than 620 MPa[90 ksi]), no qualification testing is required.

Groove welds not meeting the dimensional requirementsof Figures 2.4 or 2.5 are qualified using the ProductionProcedure WPS test of 5.13, regardless of welding pro-cess and filler metal. Test Plate C, Figure 5.3, is alsowelded and tested to evaluate the joint configuration andsoundness of the weld (see 5.7.7).


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Fillet WPSs, with the exception of those made usingSMAW with filler metal described in Table 4.1 (see5.11) are qualified using a PQR from a satisfactorygroove weld WPS qualification test or pretest. ForFCAW-G and SAW groove welds made using filler met-als described in Table 4.1, a Maximum Heat Input test,Maximum-Minimum Heat Input test, or Production Pro-cedure WPS test may be used. For FCAW-S, GMAW,ESW, and EGW processes, and the SMAW process withvery high strength electrodes as described in Table 4.2,only Production Procedure WPS tests may be used. Inaddition to the mechanical properties testing of thegroove weld WPS qualification test, a fillet weldsoundness test using a Figure 5.1 detail is required (seeC-5.10.3).

C-5.10.1 Groove Weld PQRs. Tests of groove weldsare used to determine the mechanical properties of bothgroove welds and multipass fillet welds. For the purposeof WPS qualification testing, fillet welds are qualified bygroove welds made under the same basic welding condi-tions. There is no practical method to measure the ductil-ity and toughness of small single-pass fillet welds.

All groove weld qualification testing is done by multi-pass welding. Multipass welding may create a build-upof alloys that may cause cracking in fillet welds. Thisbuildup is less likely to occur in high-dilution, single-passfillet welds. Fillet welds are stressed by shear on theeffective throat of the weld, regardless of the direction ofapplied stress in the member. They are not subjected tocalculated tensile stress on the weld throat, or effectivearea, even though they may be part of a tension member.

C-5.10.2.1 Fillet Weld Mechanical Properties. Themechanical properties of single-pass fillet welds are notmeasured by the tests described by the code, but neitherare the properties of single-pass PJP groove welds orother small groove welds. The quality of fillet welds isevaluated by macroetch test required in 5.10.2.1. If spe-cial fillet weld mechanical property tests are desired, therequirements for such tests need to be specified in thecontract documents. Testing of fillet welds, other thanthe required macroetch tests, should only be consideredfor unusual welding applications.

C-5.10.2.2 Fillet Weld Soundness Test. When single-pass fillet welds are to be used, a test weld using themaximum size single-pass fillet weld is required. Whenmultiple-pass fillet welds are used, a fillet weld sound-ness test using the minimum size multiple-pass filletweld from each WPS is required. Both welds may bemade using one Test Plate D, as shown in Figure 5.8,welding on opposite sides of the tee stem. For the WPSposition and polarity to be tested, the tests are conductedusing the mean WPS current and mean WPS voltage.

Each of these tests is to evaluate the fillet weld applica-tions most likely to have soundness problems.

Figure 5.8 specifies minimum thicknesses of steel to beused in the fabrication of the T-joint specimen. All thevalues shown are minimum dimensions. A Contractormay wish to qualify, for example, a single-pass filletweld of 8 mm [5/16 in], and a multiple pass fillet weld of12 mm [1/2 in], on the same test assembly. To do so, T2is at least 12 mm [1/2 in] and T1 is at least 25 mm [1 in].Note 1 allows the substitution of the maximum produc-tion plate thickness for either T1 or T2 should those val-ues be less than the values shown in the table. For bridgework, fillet welds rarely exceed 12 mm [1/2 in], so thecombination of T1 = 25 mm [1 in] and T2 = 12 mm [1/2in] is generally sufficient to meet the requirements of thetable in Figure 5.8. It should be recognized, however,that 25 mm [1 in] and 12 mm [1/2 in] plates are relativelythick when 6 mm [1/4 in] fillet welds are being qualified.The higher cooling rates associated with the heavier platemay make it difficult to deposit fillet welds with thecode-required profiles. Under these conditions, the thin-ner plates may be preferred. However, when the thinnerplates are used (such as T1 = 20 mm [3/4 in] and T2 = 6mm [1/4 in] for 6 mm [1/4 in] fillet welds), it is unlikelythat this single test plate will be suitable for making thesmallest multiple pass fillet weld because of the limita-tions of the table. In such situations, a second test assem-bly can be made of the thicker steel, and the multiplepass fillet weld qualified on that plate.

C-5.11 Prequalified WPSThe SMAW filler metal tests conducted by manufacturersor other parties as required by the filler metal specifica-tions are assumed to adequately represent the properties oflow hydrogen medium strength SMAW welds. Additionaltesting is not required.

C-5.11.1 Prequalified Tack Weld WPS. The mechani-cal properties of tack welds that are subsequentlyremelted using SAW would not significantly affect theperformance of the weld or joint, only the chemistry ofthe deposited SAW weld. With the exception of FCAW-S tack welds, the chemistry of welds deposited usingapproved filler metals do not significantly affect theproperties of the SAW deposit (see C-5.7.9). All otherrequirements for welding also apply to tack welds,including preheat, unless remelted using SAW (see C-3.3.7.1).

This provision applies only when tack welds are com-pletely remelted by subsequent SAW. When the tackwelds are not remelted by SAW, or when the tack welds


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are welded upon by any other process, whether remeltedor incorporated into the final weld, WPS qualification test-ing of non-SMAW tack welding WPSs is required.

In many situations, tack welds tend to be very smallwelds which naturally involve low levels of heat input.When these tack welds are remelted, the potentiallyharmful effects of the low heat input weld are effectivelyeliminated due to the remelting by the subsequent weld.This is not the situation, however, when the tack weldsare incorporated into the final weld (e.g., not remelted).Tack welds that are not remelted should be treated as aregular production weld that is incorporated into the finalweld. This involves qualification testing, and conform-ance to all the other code requirements. If a Contractorattempts to qualify a low heat input WPS that is used fortack welding, it is unlikely that the required mechanicalproperties and soundness will be achieved in the qualifi-cation test. When tack welding utilizes welding parame-ters that are similar to typical WPS welding, achievingthe requirements for WPS qualification is more readilyaccomplished, and the production welding is of theappropriate quality.

C-5.12 Heat Input WPS

This method of WPS qualification testing is limited to theSAW and FCAW-G processes, with filler metalsdescribed in Table 4.1. For these processes and filler met-als, the WPSs may be qualified, or pretested and verified.

Heat input (H), sometimes called energy input, is a mea-sure of the amount of electrical energy that is associatedwith the welding arc. If 100% of the electrical energywere converted to thermal energy, and if 100% of thethermal energy were transferred to the weld deposit, heatinput could be used to directly compute cooling rates thatoccur in the weld and the HAZ. However, not all of theelectrical energy is converted directly to thermal energy,and not all of the thermal energy is transferred to theweld deposit. Some of the electrical energy is convertedto visible light, noise, etc. Some of the thermal energy isnot transferred to the weld deposit, but rather results in thevaporization of metals, generating fume. Some energy isused to melt slag. Most of the energy used to heat andmelt the electrode is ultimately introduced into the weldthrough the hot metal droplets, although some is lostthrough spatter. For theoretical work, an efficiency factoris often added to the heat input equation to account forthese losses. This is not done in the code because itwould have no particular effect on how heat input is usedfor control of WPSs.

Heat input is used to combine the variables of current(amperage), electrical potential (voltage), and travel speedinto one term. The same inaccuracies that exist in thecomputation of heat input also occur in both WPS quali-fication testing and in production, minimizing the effectof these inaccuracies. Numerically equivalent computedvalues of heat input for SAW and SMAW, for example,may have significant differences in the actual thermalenergy delivered to the weld deposit. SAW transfers asignificant portion of the computed electrical energy intothe weld deposit as thermal energy since it does notinvolve an open arc that generates visible light, large lev-els of fume, or high levels of heat conduction to theatmosphere. Some thermal energy in SMAW is lostwhen hot weld stubs are discarded. Differences betweenwelding processes have little consequence in the applica-tion of the code, however, because WPS qualification isbased on each welding process.

Heat input is approximately proportional to the cross-sectional area of the individual weld bead deposited.Small weld beads will be associated with lower levels ofheat input, and larger individual weld passes will natu-rally result in higher levels of heat input. The heat inputassociated with fillet welds is proportional to the squareroot of the leg size (see Annex G, Figure G.4). Single-passfillet welds of a given size are therefore closely linked toa specific heat input for a given welding process.

For a given WPS qualification, the type of electrode,solid or cored, does not change. Solid electrodes areof the same AWS classification. FCAW electrodes,SAW flux, and shielding gas or gas mixture areof the same classification, manufacturer’s brand andtype. Current type, polarity, and electrode extension allremain the same, except that electrode extension mayvary by less than 20 mm [3/4 in] in SAW or 6 mm[1/4 in] for FCAW-G without requiring requalification(see C-5.12.1.2).

C-5.12.1 Maximum Heat Input. Excessively highwelding heat input often reduces weld metal toughness;therefore WPSs need to be qualified by testing at themaximum welding heat input, and production welding iscontrolled so that test parameters are not exceeded. Withthis testing method and production control, the weldsthat are produced should possess the required strength,ductility and toughness, regardless of the combination ofvariables used to compute the heat input. Weld sound-ness, however, may be affected.

Care should be taken to prevent the buildup of interpasstemperature beyond the maximum expected in the worksince weld metal strength and toughness may deteriorateat excessively high interpass temperatures. Placing a jetof compressed air behind the joint between passes is


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allowable, but experience has shown that this accelera-tion of cooling can lead to unacceptable strength levelsand deteriorations in notch toughness. This practiceshould never be employed in production, and eventhough allowed for the qualification test plates, shouldonly be done with caution and knowledge. A preferredmethod of temperature control is to wait for the test plateto cool between weld passes.

C-5.12.1.1 Electrodes. The number of electrodes isan essential variable in the test. The diameter of the elec-trodes is not. An essential variable is defined as a changein a WPS parameter that requires requalification of theWPS. Changing electrode size for a given current, volt-age and travel speed will not change the computed heatinput. It may, however, change the weld bead shape andmay affect weld soundness.

The number of welding electrodes being operated simul-taneously has a major effect on the WPS and therefore isincluded as an essential variable. The diameter of theelectrode(s) is less important in this method of qualifica-tion testing because it is based upon welding heat input.Operating current generally is increased with an increasein electrode diameter. High currents can be obtained byoperating small electrodes at high wire feed speed rates,and relatively lower currents can be obtained by operat-ing large electrodes at slower wire feed speed rates. Thecode allows current to be controlled by controlling thewire feed speed (see 4.27).

C-5.12.1.2 Electrical Parameters. Welding parame-ters can be controlled with either wire feed speed oramperage. In a constant voltage system, an increase inwire feed speed results in an increase of current, all otherconditions being equal. Although some welding equip-ment may contain an adjustment mechanism that indicatesthat welding current is being controlled, such controlssimply regulate the speed at which the electrode is deliv-ered to the arc. Current is dependent upon the weldingpolarity, electrode diameter, and electrical stickout, inaddition to the wire feed speed. Controlling wire feedspeed is a more precise method of controlling weldingparameters, although some equipment is not capable ofdirectly reading wire feed speeds. For computation ofheat input, current is still required, and conversion chartsare available to correlate current to specific wire feedspeeds. It is essential that the correlation considers theeffects of polarity, electrode diameter, and electrodeextension (see 4.27).

Current type may be either alternating current or directcurrent, AC or DC. Polarity is the sign of the current,electrode positive or electrode negative, and determinesthe direction of the flow of electrons across the arc. For agiven wire feed speed, operating arc welding equipment

DC electrode positive, frequently referred to as reversepolarity, produces deeper penetration than DC negative.For a given wire feed speed, DC electrode negative, alsocalled straight polarity, produces shallower penetrationthan DC positive. AC changes polarity 120 times persecond, and therefore depth of penetration is between thetwo.

The electrode extension, also called stickout, is definedas the distance from the end of the contact tip to the startof the arc. However, from a practical point of view, elec-trode extension is often measured between the contact tipand the work. Either approach is allowable provided it isconsistently applied in both qualification testing and pro-duction. A significant increase in electrode extensionwill result in a decrease in welding current if the wirefeed speed is unchanged. With increased electrode exten-sion, the electrode is heated by electrical resistance, rais-ing the temperature of the electrode and reducing thenecessary amperage to melt the electrode. There is a sig-nificant voltage drop across the electrode extension, andin order to maintain an adequate arc voltage, the voltageis increased to compensate for this drop. Although thewelding current decreases for a given wire feed speed, ifthe travel speed is maintained constant, the heat input ofwelding does not decrease as significantly as thedecrease in current because there is an increase in volt-age. The code allows variation in electrical stickout of upto 20 mm [3/4 in] for SAW, and 6 mm [1/4 in] for FCAWand GMAW without requiring requalification. Changesthat exceed this range require requalification.

The electrical resistance supplied by the electrode islargely dependent upon the cross-sectional area that con-ducts the electrical current. For solid electrodes, theentire cross section can be used to conduct current. ForFCAW electrodes, the current is primarily carried by theelectrode sheath. Therefore, for a given diameter of elec-trodes, the electrical resistance for a FCAW electrode issignificantly greater than that for a solid electrode. Forlarger diameter electrodes, the resistance is less than thatassociated with smaller diameter electrodes. SinceFCAW-G typically uses smaller diameter electrodes thanSAW, and always uses FCAW electrodes, small changesin the electrode extension, the length of electrode subjectto heating, may have a significant effect upon electrodeheating. In contrast, SAW with larger diameter, solidelectrodes will be affected to a lesser extent. Therefore,changes in electrical stickout that require requalificationare more restrictive for FCAW-G than for SAW.

Electrode extension is an essential variable only for thewire-fed welding processes. It has no applicability toSMAW.


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C-5.12.1.3 Maximum Current. Current is set at themaximum value to be used in production welding.Because the current used in the PQR will establish themaximum current that can be used in production, theContractor selects the level of current to ensure thathigher current levels that may be desirable in productionhave been incorporated into the testing conditions (seeC-5.12.3.2).

C-5.12.1.4 Maximum Voltage. Voltage is set as themaximum value used in production welding. The maxi-mum voltage selected for the PQR needs to be carefullyconsidered by the Contractor because this value willlimit the maximum that can be used in production. Thisis particularly important with respect to electrode diame-ters because, for a given current, smaller diameter elec-trodes typically use higher levels of voltage (see 5.12.3.2).

The voltage of interest is the voltage between the contacttip and the work piece, not the total system voltage thatincludes voltage drops across welding leads and work (orground) leads. Power source meters typically read totalsystem voltage and should not be confused with the volt-age between the contact tip and work. It is possible, forexample, to use higher system voltages in productionthan those utilized for the PQR test plate, provided theproduction voltage from the contact tip to the work isequal to or less than the same voltage as measured duringthe performance of the qualification testing. Contact tipto work piece voltage may be measured directly whenusing automatic welding processes, but would be difficultwith semi-automatic processes. Commonly for both auto-matic and semi-automatic welding, voltage is measuredfrom wire feeder to workpiece.

An increase in arc voltage will increase the amountof alloy absorbed from SAW alloy or active fluxes (seeAnnex C and C-5.5.2 for the definition of active, alloyand neutral fluxes). The most common elements pickedup from voltage sensitive active SAW fluxes are manga-nese and silicon. Active fluxes are restricted to one andtwo-pass welds, unless approved by the Engineer (see5.5.2). Active flux used with relatively high manganese,high silicon electrodes and operated at high welding volt-age may increase the amount of manganese and silicon inthe weld to unacceptable limits, causing the weld to behard and brittle. Alloy fluxes are not, by definition,active fluxes, but the alloy elements, principally nickeland chromium, absorbed from the flux generally do notbuild-up to unacceptable limits. Alloy fluxes may beused to make multipass welds without the approval of theEngineer (see 5.5.2 and C-4.8).

C-5.12.1.5 Minimum Gas Flow. The shielding gasflow rate is specified to be the minimum allowed by theWPS, to evaluate the effect of minimum shielding on

weld soundness and mechanical properties. Minimumflow rate will also minimize weld cooling, but this varia-tion has little effect.

C-5.12.1.6 Minimum Preheat/Interpass Tempera-ture. This provision was significantly changed from theprevious editions of the code. In the past, preheat andminimum interpass temperature were dictated by produc-tion welding. This created the occasional conflict when aWPS qualified with preheat values of Table 4.4 con-flicted with values described in Clause 12. To ensure uni-formity between the WPS qualification conditions forWPSs used for redundant and nonredundant work, theminimum preheat and minimum interpass temperatureswere changed to be specific values. Thus, all WPS quali-fication tests now use the same preheat level.

The expectation of the maximum heat input test is thatlow cooling rate conditions would be developed. There-fore, the preheat value is set at a relatively high level tofacilitate slow cooling. Production preheat should be asdetermined by the tables in Clause 4 or 12, as applicable.

C-5.12.1.7 Maximum Interpass Temperature.After welding has begun, the interpass temperature on asmall test specimen will begin to rise. During the WPSqualification test, the interpass temperature should beallowed to increase until the maximum value of interpasstemperature is achieved. It is then possible to allow theplate to cool between passes so that the maximum inter-pass temperature desired for the WPS is not exceeded.The maximum WPS value to be used in production willbe determined by the maximum heat input test.

C-5.12.2 Maximum-Minimum Heat Input. When theContractor plans to perform welding in conformancewith 5.12.3.3 and 5.12.3.4, qualification is based uponMaximum-Minimum Heat Input testing. Qualificationtesting and pretesting are done using Test Plate A, Figure5.1. Verification tests are performed using Test Plate B,Figure 5.2.

Maximum-Minimum Heat Input testing, also referred toas “envelope” testing, is allowed when the only change inthe WPS, between a high heat and low heat WPS, iscaused by a change in electrode diameter, current, volt-age, or travel speed. The type of electrode, solid or cored,remain the same. Solid electrodes will be of the sameAWS classification. FCAW electrodes, SAW flux, andshielding gas or gas mixture will be of the same classifica-tion, manufacturer’s brand and type. Current type, polar-ity, and electrode extension remain the same, except thatelectrode extension may vary by less than 20 mm[3/4 in] in SAW or 6 mm [1/4 in] for FCAW-G andGMAW without requiring requalification (see C-5.12.1.2).


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The Maximum-Minimum Heat Input test was developedfor filler metals described in Table 4.1 to minimize therequired number of qualification tests. The high heatinput portion evaluates WPSs that may result in lowCVN test values and/or low yield and tensile strengths.The low heat input portion evaluates WPSs that mayhave a greater incidence of fusion discontinuities orhigher hardness that may adversely affect soundness andmechanical properties. The SAW and FCAW-G WPSsdescribed in Table 4.1 have a long history of satisfactoryperformance and are expected to perform well in bridgeconstruction if qualification tests at both high and lowwelding heat inputs verify conformance to code require-ments (see 4.25 and 4.27 for control of welding variablesduring production welding).

Care should be taken when welding any heat-treatedsteel, particularly quenched and tempered steels, toensure that the maximum heat input from welding doesnot exceed the steel manufacturer’s recommendations.Excessive heat input may lower the toughness of theHAZ.

C-5.12.2.1 Maximum Heat Input. See C-5.12.1.

For the maximum/minimum heat input test method, themaximum heat input test is conducted in exactly thesame manner as would be done if only the maximumheat input test were conducted in conformance with5.12.1. Only the minimum heat input test, as described in5.12.2.2, is additionally required.

C-5.12.2.2 Minimum Heat Input. These low heatinput tests verify that welding at the minimum heat inputto be used in the work will produce sound welds, free ofcracks, that have the required strength, ductility, andtoughness. Because test plates are significantly smallerthan typical bridge girder flanges, these become hotterfrom the welding heat more rapidly. The interpasstemperature will be monitored and limited so that testplate temperatures approximate the minimum preheattemperature.

The goal of the minimum heat input test is to createwelding conditions that are representative of the highestcooling rate that would be encountered using that par-ticular WPS. The minimum preheat and interpass tem-peratures are to be used in testing, along with minimumheat input levels, creating some practical problems.

C-(1) See C-5.12.1.1.

C-(2) See C-5.12.1.2

C-(4) Voltage is set as the minimum value used in pro-duction welding. In SAW, low voltage may also producethe minimum alloy content in the weld. In order toexpand the range of suitable voltages when this method

is used, the voltage tested should be reduced from themaximum value. For example, if the minimum heat inputtest is made with a travel speed that is twice as great asthe maximum heat input test, a 50% decrease in heatinput would be computed, all other variables being thesame. However, if the voltage is not changed, theincrease in heat input range is of limited value if thedesired objective is an increased voltage range on theWPS.

C-(5) The shielding gas flowrate is set at the maximumto cause the greatest amount of weld cooling and todetermine if there is any associated adverse effects.

C-(6) For the minimum heat input test, a high cooling rateis the objective. To ensure that this high cooling rateoccurs, the preheat for the test plate is between 10°C and40°C [50°F–125°F]. If the test plate is below 10°C [50°F],it can be warmed to a temperature not to exceed 40°C[125°F]. 40°C [125°F] was selected to ensure that artifi-cial cooling of the plates would be unnecessary undermost conditions.

C-(7) The goal of the minimum heat input test is toachieve a rapid cooling rate. The interpass temperaturehas a specific maximum value to ensure that high coolingrate conditions are achieved. This value is imposed onthe test only, and need not be applied to production weld-ing. It is possible to artificially cool the test platebetween passes although such cooling may negativelyaffect the obtained test results.

C-5.12.3.1 Maximum Heat Input Envelope. Limitedchanges, as allowed in 5.12.3.1 and 5.12.3.2, are notexpected to have any adverse effect upon required weldmetal properties. To minimize WPS qualification testing,the Contractor may test with only the maximum weldingheat input condition intended for use, then operate thewelding equipment within 60% and 100% of the heatinput of the tested WPS, as well as within the limitationson current and voltage within this subclause. Travelspeed is not specifically limited by this method. How-ever, the highest travel speed that can be employed maybe computed by taking the lowest heat input allowable(60%) and the highest current and voltage allowable(100%), computing that the highest allowable travelspeed will be 1.66 times the tested parameters. This max-imum value of travel speed may only be used with themaximum amperage and voltage allowed. Similarly, theminimum allowable travel speed may be determined withthe use of the maximum heat input (100% of that tested)with the minimum allowable current (80%) and mini-mum voltage (86%), resulting in a minimum travel speedof 69% of that tested.

C-5.12.3.2 Maximum Heat Input PQR Current,Voltage, and Travel Speed. The selection of current,


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voltage and travel speed affects weld metal properties.Voltage affects weld properties through changes in thechemical composition of the weld metal, as well assoundness, wetting and the formation of discontinuitiessuch as porosity. Current affects properties through weldsolidification patterns, cooling rates and penetration.Production welding is not expected to be performed at acurrent or voltage higher than that qualified by test.

Current is roughly proportional to wire feed speed. Highcurrent can be produced using relatively small electrodesat high wire feed speeds. The controls listed are intendedto ensure that production welding is properly regulatedand that the welding variables are based upon the resultsof successful qualification tests.

After current and voltage have been selected, the travelspeed should be adjusted to produce the required heatinput, weld size and profile. Decreases in welding heatinput from the maximum tested may be obtained byreducing the current no more than 20%, or by reducingvoltage no more than 14%, or both. If current is reduced20% and voltage by 14%, travel speed may be increasedby only 14% in order to maintain heat input at the mini-mum of 60% of the tested Maximum Heat Input. Changeswithin the limits allowed by the code should have noadverse effect on the mechanical properties of the weldmetal.

C-5.12.3.3 Maximum-Minimum Heat Input Enve-lope. When the Contractor plans to operate WPSs quali-fied in conformance with the provisions of 5.12.2 over arange of welding heat inputs, the highest and the lowestwelding heat inputs are usually qualified in separatetests. High heat input may adversely effect toughness,strength and soundness. Low heat input may adverselyaffect toughness, soundness or ductility. If the tests of theWPSs that represent the upper and lower heat input lim-its produce satisfactory results, the Contractor may writeand use WPSs that operate anywhere between the maxi-mum and minimum heat input limits, staying within thetested range limitations for voltage and current. Travelspeed may be adjusted without limitation to stay withinthe bounds of the tested heat input range.

C-5.12.3.4 Maximum-Minimum Heat Input Cur-rent, Voltage, and Travel Speed. Production weldingshould not be performed at currents or voltages thatexceed the maximum or fall below the minimum limitsqualified by test. Testing is done at both the maximumand minimum limits of current and voltage under theprovisions of 5.12.2. Production welding is expected tostay within those limits, and the travel speed is adjustedas necessary to conform to minimum and maximum heatinput limits.

The Contractor should carefully evaluate whether theperformance of a minimum heat input test will actuallysupply additional flexibility for WPSs to be used in pro-duction. Subclause 5.12.3.2 allows current decreases of20% and voltage decreases of 14%. To benefit from theMaximum-Minimum Heat Input qualification method,the Minimum Heat Input test should be performed withcurrent and voltage levels lower than these valuesallowed by the Maximum Heat Input test. The theoreticalrange of travel speed allowed by the Maximum HeatInput test of 12.3.2 was shown to be 69% to 166% of thattested. Therefore, the Minimum Heat Input test shouldutilize travel speeds of at least 166% of the maximumvalue. If the allowable minimum (80%) current, mini-mum (86%) voltage, and maximum (166%) allowabletravel speed of the Maximum Heat Input test are used,the computed minimum heat input will be 41% of thattested, lower than the 60% of tested value allowed by theMaximum Heat Input test alone. Although the allowedrange of heat input has been extended, this would beachieved only when the specific combinations of current,voltage, and travel speed are used. Although the heat inputrange has been extended, there are not similar extensionsapplicable to currents, voltages, or travel speeds whencompared to the Maximum Heat Input method.

Rather than conducting a Minimum Heat Input test,many Contractors have found it advantageous to run asecond Maximum Heat Input test using a lower nominallevel for the maximum heat input. This approach can beeffective in extending the lower bound of heat input withthe second test. For example, one Maximum Heat Inputtest may be run at 3 kJ/mm [75 kJ/in] (allowing heatinputs down to 1.8 kJ/mm [46 kJ/in]), and a second Max-imum Heat Input test run at 2 kJ/mm [51 kJ/in] (allowingheat inputs down to 1.2 kJ/mm [31 kJ/in]). A calculatedheat input of 1.0 kJ/mm to 1.2 kJ/mm [25 kJ/in to31 kJ/in] is typically the lowest commonly associatedwith the typical smallest fillet weld (6 mm [1/4 in]) usedon bridge members.

C-5.13 Production Procedure WPS

This method of WPS qualification may be used for anydescribed welding process and welding consumable.Processes described in Table 4.1 (SMAW, SAW, andFCAW-G) may be qualified and controlled during weld-ing using either 5.12 or 5.13, at the Contractor’s option.Production Procedure WPS qualification described inthis subclause are to be used for all processes describedin Table 4.2, which includes all GMAW, FCAW-S,ESW, and EGW processes, and certain high-strength


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SMAW, FCAW-G, and SAW filler metals on givensteels.

This method of WPS qualification is also used for non-standard welded joint details (those not detailed asshown in Figure 2.4 or 2.5). The WPS is tested usingstandard Test Plate A (Figure 5.1), and the suitability foruse in the given joint detail confirmed using Test Plate C(see Figure 5.3).

C-5.13.1 Filler Metals Not Described in Table 4.1. AllWPSs not qualified by the tests described in 5.12, withthe exception of prequalified SMAW WPSs, are quali-fied by the Production Procedure Test of 5.13. All WPSsqualified using the Production Procedure Test areexpected to be used within the limitations of essentialvariables described in Table 5.3. Changes in weldingvariables that exceed the limits of Table 5.3 necessitaterequalification.

C-5.13.2 Nonprequalified SMAW WPS. High strengthSMAW WPSs, using electrodes with a minimum speci-fied yield strength above 620 MPa [90 ksi], are to bequalified using the Production Procedure WPS testmethod of 5.13.

C-5.13.3 Limitations. Limited variations from the exactWPS welding variables used to qualify a WPS may beused. Exceeding the variations allowed in Table 5.3 mayaffect the mechanical properties, chemical composition,or soundness of the weldment, and therefore is prohibitedwithout requalification. These variables are referred to asessential variables, and are to be specifically listed in theWPS and followed during welding.

When a WPS is qualified using the Production ProcedureTest under the provisions of 5.13, the Contractor weldsthe test plate(s) in conformance with the WPS beingqualified, and records the values for all essential vari-ables for the process listed in Table 5.3, on a form similarto Form L-1, Procedure Qualification Record (PQR),included in Annex L.

The PQR is used to record all the welding variablesrequired to be described by Table 5.3, and the resultsachieved from the qualification test. The WPS (see FormL-2, Annex L) details the joint being welded and pro-vides all essential variables for production required to bedescribed by Table 5.3.

Both forms are completed, showing all applicable data,even though there may be some repetition. Table 5.3should be checked to ensure that no WPS essential vari-able has been overlooked.

In previous editions of the code, it was possible to qual-ify different values of preheat by the conduction of a Pro-duction Procedure Qualification Test that employed

different preheat values. It was subsequently determinedthat qualification of preheat values below the levels con-tained in Table 4.4, or Table 12.3, 12.4, or 12.5, was notthe intent. Therefore, changes were made to prescribe thepreheat conditions for the Production Procedure Test.The values as contained in 4.2 are maintained for thistest. Production preheat and interpass temperatures aregoverned by other code requirements.

C-Table 5.3 (1–3) Filler Metal Type. The provisions of5.5.1 apply to qualification using any of the WPS qualifi-cation test methods, under either 5.12 or 5.13. SAW iscommonly qualified using the methods of 5.12 and arenot subjected to the essential variable limits of Table 5.3.However, high strength SAW and SAW in nonstandardjoints are qualified using 5.13, and these applications aresubjected to the limitations of Table 5.3.

For SAW, each AWS filler metal classification of bare,solid electrode and each manufacturer’s brand and typeof cored electrode or SAW flux used require qualifica-tion (see C-5.5.1). SAW flux or metal additions that areused to significantly modify the chemistry of the weld, orsupplement the filler metal volume, or both, are essentialvariables. Alloy fluxes are used to make welds more cor-rosion resistant and may be used to modify mechanicalproperties. Additions of metal powders, or cut wire, tothe SAW molten weld pool present complications inensuring weld soundness and uniform weld metal proper-ties. When the chemistry or mechanical properties of theweld are dependent upon metal additions, the use ofthese products constitutes an essential variable.

C-Table 5.3 (4) Electrode Diameter. A major differ-ence between qualification under 5.12 and 5.13 is thatelectrode diameter (size) is an essential variable in 5.13but not in 5.12 [see C-5.12.1.1 and C-5.12.2.2(1)]. Achange of two or more standard diameters, as describedin the AWS A5.XX electrode specifications, requiresrequalification if the Production Procedure WPS qualifi-cation test is used.

C-Table 5.3 (5) Number of Electrodes. A change in thenumber of electrodes used is an essential variable regard-less of the method used to qualify WPSs. Changing fromsingle to multiple electrodes, or vice versa, may signifi-cantly affect heat input and cooling rates.

C-Table 5.3 (6–12) Electrical Parameters, TravelSpeed and Heat Input. These provisions addresschanges in electrical controls that are considered essen-tial variables, and also include travel speed which is notelectrical, but is a factor in heat input. Electrical controlsand travel speed, in combination, control welding heatinput.


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C-Table 5.3 (6) Amperage. The recommended currentranges provided by SMAW electrode manufacturers areusually quite broad, and it is typically difficult to weldoutside these ranges. If satisfactory welds are being pro-duced, it is generally taken as evidence that the currentand voltage are acceptable. However, when it is knownthat the Contractor wishes to use current values beyondthose recommended by the manufacturer of the electrode,qualification is required.

The Contractor specifies the current in the WPS. Varia-tions exceeding the specified limits necessitate requalifi-cation. Current determines the electrode meltoff rate, andtherefore the volume of individual weld passes for anygiven travel speed. Electrode extension or contact tube towork distance is an important welding variable thataffects the current as well as the transfer mode. At agiven wire feed speed, using a constant-voltage powersource, longer electrode extensions cause the weldingcurrent to decrease. This may reduce weld penetration,heat input and cause fusion discontinuities. Shorterextension causes an increase in welding current. Formachine operation, electrode extension may be premea-sured; for manual welding, it is visually estimated [see C-5.12.1.2 and C-5.12.2.2(2)].

C-Table 5.3 (8) Mode Transfer. The mode of metaltransfer across the arc affects weld soundness.

See C-Table 5.3 (11, 13) and C-5.12.1.2 or C-5.12.2.2(2)for discussion of current, polarity, and electrode exten-sion. Electrode extension is not an essential variable.When WPSs are qualified under the provisions of 5.13,the Engineer should determine when changes in electrodeextension appear to have changed welding conditionssufficiently to require proof of acceptable mechanicalproperties by requalification.

C-Table 5.3 (9) Voltage. The Contractor specifies thevoltage in the WPS. Variations exceeding the specifiedlimits necessitate requalification. In SAW, arc voltagecan have a major effect on the chemistry of the weldmetal [see C-5.12.1.4 or C-5.12.2.2(4)].

With SMAW, arc length determines voltage. All SMAWperformed under the provisions of the code uses lowhydrogen SMAW electrodes that require a very short arclength, commonly 1 mm to 2 mm [1/32 in to 1/16 in].

C-Table 5.3 (11) Travel Speed. Travel speed affectsbead size, heat input, and weld cooling rates, especiallyimportant for fracture toughness control and for weldingquenched and tempered steels. Proper selection of travelspeed is necessary to provide weld soundness and avoidincomplete fusion and slag entrapment.

Significant changes in travel speed change the solidifica-tion pattern in the weld pool. Welding using high travel

speeds and high current, identified by long teardropshaped weld puddles, can be undesirable because itcauses lower melting point (weaker) constituents, ifpresent in sufficient quantities in the base metal, to bepushed to the center of the weld where they may causehot cracks. Qualification testing evaluates susceptibilityto hot cracking, but this is also highly dependent uponjoint configuration.

SAW, ESW, and EGW travel speeds are allowed agreater range of variation, compared to GMAW andFCAW, because with these processes, travel speed canoften be substantially changed without interfering withthe operation of the welding arc.

C-Table 5.3 (12) Heat Input. Large changes in heatinput significantly change the mechanical properties ofthe weld and HAZ, and are not allowed without requali-fication. Excessively high welding heat input may signif-icantly reduce weld metal and HAZ toughness,especially for heat treated steels. Lower welding heatinput may increase the incidence of fusion discontinui-ties and affect soundness and mechanical properties,including decreasing toughness.

C-Table 5.3 (13) Flow Rate. Changes in the shieldinggas flow rate may change the effectiveness of the shield-ing cover. Procedures qualified under 5.13 are subject tothese flow rate limitations.

C-Table 5.3 (14–18) Multiple Electrode SAW. It isphysically possible to perform SAW with multiple elec-trodes spaced far enough apart that the molten weld poolfrom a leading arc solidifies before the trailing arc or arcsreach the same point in the weld. To reliably achievefusion under such conditions, the trailing arc would alsohave to be close enough to make the second weld beforethe slag on the first weld solidifies. When welding with aGMAW lead arc and a SAW trailing arc or arcs, the leadarc is allowed to feed a separate weld pool. GMAW pro-duces minimal slag (see C-4.10.5 and C-4.11.5).

In SAW, the maximum spacing between lead and trailarcs that feed the same molten weld pool is about 20 mm[3/4 in]. The maximum spacing between multiple arcs inseparate puddles is 75 mm [3 in].

C-Table 5.3 (19) Groove Area. Requalification isrequired if the number of weld passes changes by morethan 25% for a given cross-sectional area of groove orfillet weld. This is to control changes in welding heatinput. Because qualification and control of welding vari-ables is based upon welding heat input, it is unlikely thatrequalification will be necessary due to a change in therequired number of passes. Production welding shouldreflect WPSs already qualified by test and the number of


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required weld passes should be about the same for thesame volume of weld metal.

C-Table 5.3 (20–22) Groove Details. Any change in thejoint preparation that may make welding more difficult,increase the likelihood of fusion discontinuities, or modifymechanical properties require requalification.

C-Table 5.3 (24) Postweld Heat Treatment. At leasttwo types of postweld heat treatment are possible. Astress relief heat treatment performed as described in 4.4may significantly modify the metallurgical structure ormechanical properties of the weld or base metal. Theweldment could also be annealed, normalized, orquenched and tempered, any of which would signifi-cantly alter the metallurgical structure and affectstrength, ductility and toughness. Normalizing and tem-pering heat treatments may improve or deteriorate tough-ness. Stress relief typically increases toughness and reducesstrength.

Heat treatment of bridge weldments is rarely performedand is generally unnecessary. Properly designed and con-structed bridge weldments have excellent fatigue lifewithout heat treatment. Postheating at temperaturesbelow 260°C [500°F] is done to remove hydrogen and isnot considered PWHT. If the bridge member is to be heattreated to stress relieve the weld and HAZ, or is to beheat treated to improve its mechanical properties byrecrystallization and transformation, the WPS qualifica-tion test plate(s) receive the same heat treatment beforetest specimens are removed by machining. Test speci-mens removed from heat treated welds are not to bereheated for any purpose.

C-Table 5.3 (25) Groove Welds in AASHTO M270M[M270] (A 709M [A 709]) Grade 690/690W [100/100W]Steels. The plate thickness variation limitations applica-ble to these high strength, quenched and tempered steelsprovides closer control of welding heat because of con-cern over fusion discontinuities and cracking.

The limits on the thickness variation are based upon theeffect of thickness on cooling rate. Cooling rate is criticalin quenched and tempered steels, significantly affectingthe properties of the weld and HAZ. Rapid cooling cancause excessive hardness and increases the risk of hydro-gen-induced cracking. Slow cooling may lower strengthand toughness.

The HAZ of quenched and tempered steels of thisstrength level obtain their strength by transforming tomartensite and bainite during the rapid cooling followingeach weld pass. To make the weld and HAZ ductile andtough, yet sufficiently strong, the bainite and martensiteare limited by slower cooling rates at lower tempera-tures. However, if the HAZ remains hot for too long, the

HAZ may become brittle from grain growth. If the weld-ing heat input limits recommended by the manufacturerof the base metal are exceeded, strength and toughness ofthe weld and HAZ will be degraded. If the welding heatinput used in combination with the preheat and interpasstemperature is too low, low toughness and hydrogen-induced cracking may result.

C-5.14 Electroslag and Electrogas Welding

The WPSs to be used for ESW and EGW are detailed inClause 4, Part E, and the essential variables for these pro-cedures are given in both Tables 5.3 and 5.4.

C-5.14.1 Figure 5.1. ESW and EGW WPSs are qualifiedusing Test Plate A, Figure 5.1, with sufficient length toallow the removal of eight CVN test specimens. Becausemost ESW and EGW WPSs use a square butt joint prep-aration, the test plates are prepared with a square edgepreparation. If another type of groove is being used in thejoint, the groove in the test plate should match that in thejoint.

C-5.14.2 Limitations. Table 5.4 contains essential vari-ables specific to ESW and EGW, and is in addition to theessential variables described for ESW and EGW in Table5.3. If any essential variables noted as “Requalificationby WPS Test” exceed the required values, then fullretesting of the WPS is necessary. For variations in FillerMetal Oscillation only, full WPS retesting of the WPSwill not be required, but the weld made using a previ-ously qualified WPS but with revised oscillation valuesis required to be examined using either RT or UT.

C-5.15 Type of Tests and PurposeWeld test plates are first visually inspected, then radio-graphed to ensure that the WPS is capable of producingsound welds that meet all the quality requirements of thecode. If visual inspection or NDT indicates that the testweld contains unacceptable weld discontinuities, there isno need to machine test specimens and conduct testsbecause the WPS testing is still considered a failure.When acceptable weld discontinuities are very localizedand there is sufficient weld length, it is acceptable tomachine all required test specimens from areas of theweld that are defect free.

Acceptance of WPSs is based upon satisfactory achieve-ment of required mechanical values for strength, ductility,and toughness, and satisfactory quality as documentedby NDT and destructive tests for soundness. WPS quali-fication testing verifies mechanical properties based


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upon test welds. In production welding, soundness is alsoverified by visual tests and NDT.

C-5.15.1 For matching strength and undermatchingstrength weld metal in groove welds, the qualificationtesting is required to include the tests that evaluate thesoundness of the weld metal and determine the mechani-cal properties of the deposited weld metal. For under-matching applications and applications joining twodifferent base metal strengths with a filler metal match-ing the lower strength, reduced section tensile tests andside-bend specimens are not required because, due to themismatch in strength properties, it is impractical tomechanically test these combinations.

C-5.17 Nondestructive Testing (NDT)All WPS qualification test plates are required to beradiographed to demonstrate soundness before mechani-cal testing, regardless of the welding process used. Addi-tionally, NDT testing reduces the expense and delaysthat result from machining and testing welds having dis-continuities prohibited by the code.

C-5.18.1 Under some conditions, the tensile testingcapacity of a laboratory may preclude the use of full-sized specimens. This is often the case when higherstrength steels are used. Under these conditions, multiplespecimens may be used. The entire thickness of the testspecimen is tested.

Part BWelder, Welding Operator, and

Tack Welder Qualification

The qualification tests are especially designed todetermine the ability of the welders, welding operators,and tack welders to produce sound welds by followinga WPS. The code does not imply that anyone who satis-factorily completes performance qualification testing canperform the welding for which he or she is qualifiedunder all conditions that may be encountered during pro-duction welding. It is essential that welders, weldingoperators, and tack welders have some degree of trainingfor these special conditions.

The welding personnel qualification tests are specificallydesigned to determine a person’s ability to producesound welds in any given test joint. After successfullycompleting the qualification tests, the welder should be

considered to have minimum acceptable qualifications.Knowledge of the material to be welded is beneficial tothe welder in producing a sound weldment, therefore, itis recommended that before welding quenched and tem-pered steels, welders should either be given instructionsregarding the properties of this material, or have priorexperience in welding the particular steel.

C-5.21.1 Purpose. Welder qualification tests areintended to document the ability of a welder, weldingoperator, or tack welder to make sound welds by follow-ing a WPS provided by the Contractor. The test isintended to establish the ability of the individual (1) toadjust and control the equipment, (2) follow the WPS,(3) guide or manipulate the electrode to ensure soundfusion between the weld and the adjacent base metal orpreviously deposited weld pass, and (4) produce a weldthat does not contain an unacceptable number or size ofweld discontinuities such as undercut, overlap, porosityand slag inclusions. Lack of fusion or other discontinui-ties caused by poor welding technique may cause thespecimen to fail a bend test. However, if a sound weldhas insufficient strength or lacks sufficient ductility topass the bend test, it is generally not the fault of thewelder, but may be the result of an inadequate WPS orpoor test specimen preparation. Welder qualificationtests are only intended to measure the skills that are nec-essary to produce weld soundness. All other properties ofthe weld are those determined by the selection of fillermetal, base metal and the WPS.

The code does not intend to require unnecessary duplica-tion of effort. Where there is evidence that welding per-sonnel have previously been qualified by tests describedin this code and are current as described in 5.21.4,requalification should not be ordered unless there issome reason to question the skill of an individual.

C-5.21.3 Base Metal. The base metal used in weldingpersonnel qualification testing does not affect the tech-nique used by the welder, but may affect the physicalproperties of the weld and base metal during physicaltesting of the sample in bend testing. If an unlisted steel isto be welded, personnel welding on this steel qualifyusing test plates of the same specification, although notnecessarily the same grade.

C-5.21.4 Period of Effectiveness. Welding personnelqualification remains in effect (1) for six months beyondthe date that the person last used the welding process, or(2) until there is a specific reason to question the per-son’s ability. For (1), the requalification test uses onlythe 10 mm [3/8 in] plate thickness. If the welder fails thistest, or if the welder loses qualification on the basis of(2), then full qualification testing is necessary, as if for anew welder.


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Although the code allows qualification to remain ineffect indefinitely, some Owners place a limit on thelength of time an individual may be considered qualifiedto weld without repeating qualification testing. Suchrequirements are discouraged. The code intends thatthere be no unnecessary duplication of effort. Wherethere is evidence that welding personnel are qualified bytests described by this code, and qualification is currentas described in this subclause, requalification should notbe necessary unless there is some reason to question theability of an individual welder, welding operator, or tackwelder. The Fracture Control Plan requires periodicrequalification (annually), but also allows requalificationbased solely upon RT of production groove welds in buttjoints (see 12.8.2).

C-5.21.5.2 Root and Fill Pass Cleaning. Personnelare not to be qualified if they cannot consistently makewelds of proper profile and free of unacceptable disconti-nuities. Grinding and the other described actions wouldallow the correction of poor profile and the repair orremoval of discontinuities in the test plate, allowing awelder with poor or unacceptable technique to, perhaps,pass the test.

C-5.21.6.1 Contractor. The Contractor is responsiblefor the qualification of welding personnel. The Contrac-tor is not required to physically conduct the testing andmay have the testing supervised and conducted by a thirdparty, provided the Contractor verifies the adequacy ofthe third party testing.

C-5.21.7 Records. The Contractor maintains writtenrecords of welding personnel qualification testing. Suchrecords should contain information regarding date oftesting, process, WPS, test plate, position, and the resultsof the testing. In order to verify the six-month limitationon welder qualification, the Contractor should also main-tain a record documenting the dates that each welder hasused a particular welding process.

C-5.21.8 Previous Code Editions. Welding personnelqualification tests conducted using either U.S. Custom-ary or metric (SI) units of measurement are acceptable,and qualify the welder for work under both systems ofmeasurement.

C-5.24.1.1 Base Metal. Welders, welding operatorsand tack welders welding quenched and tempered highstrength steels should have experience welding such basemetals. Because of the increased risk of cracking and theeffects of welding upon HAZ mechanical properties,welding personnel welding on Grade 690 or 690W [100 or100W] steels are to be tested on steel of the same specifi-cation, Grade 690 or 690W [100 or 100W] as appropriate.

C-5.24.1.2 Process. FCAW-S and FCAW-G are con-sidered the same process for welding personnelqualification.

C-5.24.1.3 Approved Electrode and ShieldingMedium. Although a change in manufacturer within agiven classification of filler metal, change of flux, orchange of shielding gas is an essential item for WPSqualification, these are not factors in welding personnelqualification. Changes in these parameters affect theWPS, but will have an insignificant effect upon the tech-niques used for welding.

C-5.24.2.1 SMAW Restrictions. SMAW EXX18electrodes are considered to be among the more difficultSMAW electrodes to control. A welder or tack welderqualified using any EXX18 class electrode allows thewelder to use any SMAW electrode described in Table4.1.

C-5.24.3.1 ESW/EGW. Although a change in manu-facturer within a given classification of filler metal,change of flux, or change of shielding gas is an essentialitem for WPS qualification, these are not factors in weld-ing personnel qualification. Changes in these parametersaffect the WPS, but have an insignificant effect upon thesetup and operations used for these automatic weldingprocesses.

C-5.24.4.2 Position. Unlike the position limitationsfor welder qualification in 5.22.2, tack welder qualifica-tion is position specific. A welder qualified for the verti-cal position is also qualified for the flat and horizontalpositions. A tack welder qualified for the vertical posi-tion is not qualified for the flat and horizontal positions.Separate tests are necessary for each tack weld position.

C-5.26.1 Radiographic Testing. With the single excep-tion of GMAW-S, all welding personnel qualificationtesting may be done by either mechanical testing or RTof test welds.

GMAW-S is susceptible to a high incidence of fusiondiscontinuities called “cold laps.” The guided bend testsused for welder qualification produce sufficient strain inthe test specimens to cause cracking of cold lapped areasthat may be missed by RT because of size or orientation.

Welder qualification testing by RT subjects the completeweld to the same test for soundness that is the basis foracceptance of bridge welds. Bend tests only measure thesoundness of the half thickness of the weld test specimenthat is subjected to tensile stress as the specimen is bent.Discontinuities on the inside, or compression side, of thebend are often not detected. RT can also evaluate thesoundness of the root in welds made against fused steelbacking. Achieving good fusion at the root is one of themore difficult parts of the test, and accurately reflects


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difficulty in construction. Bend tests often fail to prop-erly evaluate small, but extensive, fusion discontinuitiesin the root because they are machined or ground awayduring preparation of the bend specimens.

Because test specimens do not have to be machined fromthe test weld, and because testing can be completed withmuch less lost time, welder qualification by RT may alsobe less expensive than bend testing.

C-5.26.3 Fillet Weld Break and Macroetch TestRequirements. The purpose of this test is to determinethe soundness of the fillet welded joint. The test accep-tance is determined by the extent and nature of any flawsrevealed by the rupture of the specimen, should it occur.After the specimens ruptures, the fracture surfaces shouldbe examined visually for evidence of defects such ascracks, inclusions, or lack of penetration (see 5.27.4 and5.27.5).

C-5.28 Retests

These provisions are applicable during initial weldingpersonnel qualification testing, and during testingbecause of loss of qualification from poor workmanship

or qualification expiration. For requalification because oftime limits, a limited qualification test on 10 mm [3/8 in]plate is used. For requalification because of poor work-manship, full testing is necessary, identical to testing fornew welding personnel (see 5.21.4).

C-5.28.1.1 Immediate Retest. Upon failure of awelder or welding operator to pass the qualification test,if it is desired, the welder or operator may immediatelyweld two additional test plates. If both plates pass, thenthe welder or operator is considered qualified.

C-5.28.1.2 Retest After Further Training or Prac-tice. Optionally, the welder or welding operator whofails the qualification test may continue training and/orpractice for the process and position to be qualified.Upon documented evidence of such practice or training,a single test plate may be welded. If this test plate passes,the welder or operator is considered qualified.

C-5.28.2 Tack Welder. Upon failure of a tack welder topass the qualification test, if it is desired, the welder oroperator may immediately weld an additional test plate.If this plate passes, then the tack welder is consideredqualified. This is less restrictive than the welder andwelding operator retesting provision, because only onetest plate is used rather than two.


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C-6.1 General

This part of the code was first printed in its present formin the 1981 AASHTO Welding Specifications. It wasalso printed in a slightly modified form in AWS D1.1-80.After years of work in the AWS Structural WeldingCommittee, the Structural Welding Code was changed tostate in clear and concise terms that the Contractor isresponsible for the quality of the work. Prior to thischange, the Structural Welding Code stated “The Inspec-tor designated by the Engineer shall ascertain that all fab-rication by welding is performed in conformance withthe requirements of this code.” This was often inter-preted as giving the Owner ultimate responsibility forproduct quality, a position unacceptable to Owners.

C-6.1.1 The intent of these provisions is to clearly separateresponsibilities for inspection. The Contractor/Fabricator/Erector is responsible for the quality of the work to beperformed in conformance with the provisions of thecontract documents. The Owner is responsible for theaccuracy of the contract documents and for payment foracceptable work as specified in the contract. QC istermed fabrication/erection inspection in AWS D1.1, andQA is termed verification inspection.

C-6.1.1.1 The Contractor ensures that all materialsand workmanship conform to the requirements of thecontract documents. The Contractor’s inspectors areresponsible to conduct all inspections and tests describedin the code, and also perform any additional inspectionsand tests that may be necessary to ensure that materialsand workmanship conform to all requirements of thecontract documents. The code is only part of the contractdocuments.

C-6.1.1.2 QA is the prerogative, but not theresponsibility, of the Engineer. The Engineer may: pro-vide independent QA inspection; enter into an agreementfor the Contractor to provide independent QA inspection;or waive all QA inspection based upon personal experi-ence and discretion. When the Contractor provides QAinspection services based upon an agreement with theEngineer, it is important that this inspection be com-pletely independent of the Contractor’s QC inspectionprogram, and also independent of those responsible forproduction. QA inspection is an independent system ofinspections and tests that verify that the Contractor’s fab-rication methods and QC program produce the requiredresults.

QA inspection may help to avoid errors and preventdelays. However, failure of the Engineer to discover adefect in the fabricated structural steel does not make theEngineer liable for the cost of repair, and does not obli-gate the Engineer to accept a less than acceptable prod-uct. The Contractor, not the Engineer, is responsible forthe quality of the work, regardless of whether or not theEngineer has provided quality assurance inspection.

Inspection by the Engineer or designated representativeshould be done in a timely manner to avoid delays.Repetitive or untimely inspections by QA representativesmay lead to disagreement regarding project schedule andcosts.

C-6.1.2.1 All inspectors performing QC duties do sofor the Contractor. They may be employees of the Con-tractor or subcontracted representatives. Manufacturer’srepresentatives may also provide expertise to evaluatespecial problems and recommend solutions to the QCInspector.

C-6.1.2.2 The QA Inspector, when one is assigned,represents the Engineer. When there is more than oneperson performing QA inspection, the supervising inspec-tor represents the Engineer within the limits of authoritythat are established and reports all deficiencies in materi-

C-6. Inspection


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als and workmanship to the Engineer and Contractor. Ingeneral, QA Inspectors should not be asked to commenton the structural adequacy of welded connections, mate-rials substitutions, repair methods not covered by code,or other subjects that require an opinion relating to thedesign or performance of the structure. The Inspector’sauthority is generally limited to accepting materials andworkmanship that conform to code requirements andrejecting those that do not. The Inspector does not holdthe authority to modify the contract. Questions concern-ing the adequacy of proposals to repair defective weld-ments or to substitute materials should be directed to theEngineer.

C-6.1.2.3 All Inspectors. When the code specifiesthat inspectors meet certain qualification requirements,or perform certain functions, it includes both QC Inspec-tors and QA Inspectors, unless specifically designated toeither function. All inspection and testing required bythis code is performed by QC Inspectors. QA inspectionwill be as directed by the Engineer.

C-6.1.3.1 Individuals assigned to perform inspectionfunctions and make decisions about the acceptability ofmaterials and workmanship need to be properly quali-fied. Certification of an inspector based upon successfulcompletion of the AWS Qualification and Certificationprogram, AWS QC1, is considered evidence of basiccompetence. A Senior Certified Welding Inspector (SCWI)satisfies the requirement for CWI. A Certified AssociateWelding Inspector (CAWI), because he or she has lessexperience or has achieved an insufficient test score topass the CWI or SCWI examination, does not satisfy therequirement of CWI.

Inspectors qualified by the Canadian Welding Bureau inconformance with the provisions of CSA W178.2 areconsidered the equivalent of an AWS Certified WeldingInspector.

Engineers and technicians who, on the basis of their edu-cation and experience are considered equal to an AWSCWI or CWB equivalent in their ability to performinspection functions properly, may serve as Inspectors,with the Engineer’s approval. This provision applies toboth Contractor and Engineer representatives, and isintended to prevent highly qualified individuals frombeing barred from performing inspection functions solelybecause they are not certified by AWS or CWB.

C-6.1.3.2 An inspector that was once certified underthe provisions of 6.1.3.1(1) or 6.1.3.1(2), and has contin-ued to perform acceptable welded structural steel inspec-tion, may continue to perform inspection services underthe provisions of this code. Whenever there is reason toquestion the competency or ability of an inspector, or if

documentation of ongoing work in inspection is inade-quate, the provisions of 6.1.3.5 apply.

C-6.1.3.3 The Inspector may be supported by assis-tants not meeting the qualifications of 6.1.3. Assistantinspectors should be trained and competent to performthe tasks assigned, such as checking joints during assem-bly prior to the start of welding, checking preheat andinterpass temperatures, and inspecting fillet welds.Assistant inspectors need to receive regular supervisionand verification by the Inspector of the inspection theyare providing. Monitoring of their work is expected to bedone on at least a daily basis, and more often for criticalsituations.

C-6.1.3.4 ASNT Personnel Qualification. The coderequires NDT personnel be certified under a writtenpractice developed in general conformance with ASNTRecommended Practice No. SNT-TC-1A, PersonnelQualification and Certification in Nondestructive Test-ing, or an equivalent program. Other programs mayinclude the AWS NDE Certification Program and theANSI/ASNT CP-189, ASNT Standard for Qualificationand Certification of Nondestructive Testing Personnel.

An NDT Level I individual has the skills to perform spe-cific calibrations, specific NDT, and with prior writtenapproval of the NDT Level III, perform specific interpre-tations and evaluations for acceptance or rejection anddocument the results, while under the direct supervisionof a Level II.

An NDT Level II individual has the skills and knowledgeto set up and calibrate equipment, to conduct tests, and tointerpret, evaluate and document results in conformancewith procedures approved by an NDT Level III. TheLevel II should be thoroughly familiar with the scopeand limitations of the method to which certified, andshould be capable of directing the work of NDT Level Ipersonnel. The NDT Level II should be able to organizeand report NDT results. The Level II should monitor andapprove the results of Level I personnel on at least adaily basis. The Level II is responsible for providingguidance to the Level I and reviewing and signing all testreports generated by the Level I.

An ASNT NDT Level III individual has the skills andknowledge to establish techniques; to interpret codes,standards, and specifications; designate the particulartechnique to be used; and verify the accuracy of proce-dures. The individual should also have general familiar-ity with the other NDT methods. The NDT Level III isresponsible for conducting or directing the training andexamining of NDT personnel in the methods for whichthe NDT Level III will be qualified.


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The Level III should have passed the basic and methodexaminations prescribed by SNT-TC-1A. The SNT-TC-1A tests required for Level III certification may beadministered by ASNT or an independent third partydeemed acceptable by the Engineer.

The code requires that NDT of non-FCM materials beperformed by Level II technicians, or by Level I techni-cians only when working under the direct supervision of aLevel II. Inspection by a Level III may not be recognized,as the Level III may not perform actual testing regularlyenough to maintain the special skills required to set up orto conduct the tests, nor is a hands-on “practical” exami-nation required for certification, unless certified underASNT’s ACCP testing. An ASNT Level III may conducttests if that person has passed a practical examinationand also holds a Level II certification. For Fracture Criti-cal Members, under 12.16.1.2, testing of Fracture Criti-cal Members should be done by either a certified Level IIunder the supervision of a qualified Level III, or by aLevel III certified by ASNT and qualified as a Level II,unless the Engineer accepts other forms of qualification.

C-6.1.3.5 The Engineer should verify that QC Inspec-tors and NDT personnel are qualified. Whenever there isreason to suspect that individuals are not qualified, theQA Inspector should immediately notify the Contractor’srepresentative and should withhold acceptance of thework until proof of qualification has been provided andaccepted. Proof of qualification may be in the form oftesting, retesting, or recertification.

C-6.1.3.6 NDT personnel performing only NDT neednot be qualified as visual inspectors. Qualification as anNDT technician includes provisions for vision acuitytesting on an annual basis and for color differentiationevery three years.

C-6.1.3.7 Vision acuity testing is required at leastevery three years to verify that the inspector can see prop-erly. Testing every three years is not a guarantee that theinspector’s vision will continue to remain acceptablethroughout the full three year period. If it appears thatan inspector is having difficulty seeing properly, a newvision acuity test by a qualified professional can beordered. NDT technicians should be tested annually forvisual acuity and every three years for color differentiation.

C-6.1.4 For most projects, inspectors do not need thecomplete contract documents to perform the requiredinspections. Approved shop detail drawings, copies ofcontract plan sheets, and contract-related requirementsfor materials, assembly, and welding should be available.

C-6.1.5 Inspector. Inspectors are notified in advance sothat they can be present and inspect in a timely manner.The QA Inspector schedules his or her activities to com-

plement the flow of work by the Contractor. Work donewithout advance notice to the QA Inspector, or when theQA Inspector has been denied access, may frequently berejected by the Engineer until there is proof that it meetsall requirements of the contract documents. Proper noticeavoids delays and disagreements, and also requires aresponse from the recipient.

C-6.2 Inspection of MaterialsTo ensure that all materials conform to the requirementsof the contract documents, the QC Inspector or QC staffshould review all material test reports and material certi-fications, and make a detailed visual inspection of allmaterials. The Inspector should document reviews ofmaterial reports and certifications and document visualinspections. This should be done prior to assembly sothat defective plates, shapes, studs, filler metals, bolts,etc. do not become part of the construction and have tobe removed and replaced at a later date.

C-6.3.1 All welding performed in conformance with theprovisions of this code is based upon written WPSs. AllWPSs, except those WPSs exempt from testing under theprovisions of 1.3.6, 5.11, or 12.7, are based upon theresults of acceptable WPS qualification tests. Prior to thestart of production welding the Inspector should verifythat these requirements are met and verify that the weld-ing personnel have access to the WPS that describes thewelding to be performed.

C-6.3.2 The Inspector should determine that the weldingand thermal cutting equipment to be used in the work isadequate for the intended welding or cutting operation,and is in proper working order. This inspection is toensure that the equipment is capable of providing accept-able results when used by properly trained welding per-sonnel. This includes visually examining the equipment,reading the identification and rating labels, andobserving the equipment while being operated to ensurethat it functions properly. Welding and thermal cuttingequipment should not be allowed to be used in the workif its operation frequently malfunctions and creates weldor base metal discontinuities (see 4.26.1 for inspectionfrequency of equipment).

C-6.4.1 All welding personnel are expected to hold cur-rent qualifications in order to weld (see Annex D, Termsand Definitions, for a description of the duties of weld-ers, welding operators and tack welders, and for the dis-tinction between qualification and certification).Personnel are expected to be qualified as stated in Clause5, Part B. Qualification and certification are the responsi-bility of the Contractor. Qualification by acceptance of


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previous, properly witnessed and documented qualifica-tion tests may be approved by the Engineer. Acceptanceof proper evidence of previous qualification is allowed toreduce the unnecessary duplication and expense ofretesting.

C-6.4.2 Under the provisions of 5.21.4, a welder, weld-ing operator or tack welder’s qualification may remain ineffect indefinitely. Welding personnel may be tested andqualified in more difficult welding positions such asoverhead or vertical, then use only easier positions suchas flat and overhead for an extended period of time. Thetechnique and skills needed for the rarely used, difficultpositions may be temporarily lost or reduced. For these sit-uations, requalification in the more difficult position to beused may be necessary to verify the required skill level.

Physical abilities and visual acuity generally decreasewith the passage of time. Vision deficiencies may becompensated for by the use of corrective lenses. Loss ofstrength and manual dexterity may be compensated forby increased knowledge and skill. Some people maybecome temporarily unable to weld properly for anynumber of reasons.

Should less than acceptable welding skill be detected, theInspector should take action as necessary to preventunacceptable welding from being incorporated into thework. Welding personnel that appear less than fully qual-ified, or for any other reason are unable to properly per-form the required welding tasks, should be preventedfrom continuing to weld until either requalified by test orprovided other evidence of recovery from a temporarydisabling condition.

C-6.4.3 Under 5.21.4, welding personnel qualificationremains in effect indefinitely, provided the person retainstheir skills and has used the process within the past sixmonths. Should the time period exceed six months,retesting is required but a 10 mm [3/8 in] plate test maybe used to requalify for groove welds of all thicknesses.Subclause 12.8.2 of the FCP requires welding personnelto be qualified before welding on FCM, but also requali-fied annually. For these previously qualified welders andwelding operators, requalification may be based upon theresults of radiographic testing of production welds in buttjoints.

C-6.4.4 A qualified Inspector witnesses all welding per-sonnel qualification testing and completes the requiredreports. Either a QC or QA Inspector may perform thetesting observation.

C-6.5.1 The Inspector inspects the structural steel forconformance to the contract documents regarding weld-ing. The size, length and location of all welds should beas specified. The surface of the structural steel should be

visually inspected to verify that there have been no weldsmade that are not shown on the approved shop drawingsor approved by the Engineer. Extra welds, particularlytack or temporary welds, may cause hydrogen-inducedor fatigue cracking and should be avoided.

C-6.5.3 The electrodes, fluxes and shielding gases areexpected to be used as designed. Some electrodes areintended only for use with DC power sources operatedelectrode positive or electrode negative. Others aredesigned to be used with AC power sources. Some elec-trodes that may be used to weld in a given position orpositions are not suitable for out-of-position welding.Other filler metals require a specific shielding gas mix-ture. Appropriate use of the welding materials with cur-rent AWS A5.XX specifications should be verified.

C-6.5.4 The QC Inspector should ensure that the weldingconforms to the requirements of the contract documentsby the necessary inspections. Materials should beinspected prior to assembly and during assembly. Pre-heat and interpass temperature control should be moni-tored. Welding is inspected while in progress and allcompleted welds and finished fabricated members arevisually inspected. An Inspector need not watch eachwelder full time. Regular tours through active work areasprovide the Inspector an opportunity to see each opera-tion as it progresses and affords an opportunity to seehow each welder is performing.

The Inspector is authorized to approve materials andworkmanship that conform to code requirements. Inaddition, the Inspector may approve work that is done toother standards that have been approved by the Engineer.Whenever possible, material and workmanship standardsthat need not conform to code requirements should bedescribed in the contract documents prior to bidding.

C-6.5.5 The Contractor and the various welding andinspection personnel need to know the status of weld-ments that have been completed and whether they havebeen inspected and accepted. Markings or inspectionlogs indicate those parts of the work that have beeninspected and accepted and those needing repair. Suchsystems are also used to avoid needless reinspection. Theprovisions of this subclause apply to both QC and QAInspectors, but are particularly appropriate for Inspectorsthat perform final inspection.

In many industries, the inspectors are required to marktheir acceptance or rejection directly on the welds or theadjacent steel. This is often an unacceptable procedurefor bridges, particularly those erected in the bareunpainted condition. Any method of record keeping isacceptable, provided it is clear to the Contractor andapproved by the Engineer. If die stamps are used, onlylow-stress type stamps should be used to mark accep-


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tance or rejection in areas of bridge members subject totensile stress, as other die stamp impressions may causestress concentrations that could lead to fatigue cracking.Paint sticks or ink stamps may be used for die stampswhere these marks will not be unsightly in the finishedproduct.

C-6.5.6 Detailed records are required in an effectivewelding inspection program. They should be organizedand kept as simple as possible. QC Inspectors keeprecords for the Contractor and QA Inspectors keeprecords for the Engineer. However, the QC inspectionrecords should be available for review by the QA Inspec-tor or Engineer upon request.

The use of “traveler forms” clipped to designated areasof each member and documenting all individuals (fitter,welder, inspector, etc.) and actions (assembly, tacking,welding, layout marks, stiffener installation, splice drill-ing, etc.) is helpful to both QC and QA.

C-6.5.7 The Contractor is responsible for the quality ofall NDT and necessary records of NDT results, unlessotherwise specified. The QA Inspector may witnessNDT, review NDT reports and approve and witness nec-essary repairs.

C-6.5.8 NDT reports shows which welds were tested andthe results of each test. When repairs are necessary, arecord of the repair and of the NDT of the repair is alsoprepared. It is recommended the reports be preparedpromptly.

C-6.6 Obligations of the ContractorThis subclause is only a partial listing of the Contractor’sobligations. The Contractor is responsible for the qualityof the work and ensures that it conforms to all require-ments of the contract documents.

C-6.6.1 It is essential that QA personnel have safe accessto all work and to necessary records. Cooperationbetween the Contractor, QC and QA is essential.

C-6.6.2 The Contractor provides visual inspection andall NDT inspections required by the contract. Any mate-rials and workmanship that do not conform to contractdocument requirements are to be corrected by the Con-tractor at the Contractor’s expense. Routine methods ofcorrection are described in 3.7. Some repair requiresapproval by the Engineer. Subclause 6.26 describes boththe visual and NDT weld acceptance criteria.

C-6.6.3 Any rejectable deficiencies noted by the QAInspector are to be repaired by the Contractor. The QA

Inspector should routinely communicate directly with theQC Inspector or the representative designated by theContractor. When a notice of rejection is necessary, itshould be given to the QC Inspector or the responsiblesupervisor and confirmed in writing. The Engineershould be informed when a notice of rejection is issuedand should investigate potential serious problems in atimely manner.

C-6.6.4 Faulty welding and methods of weld removalcan lead to base metal cracking because of hardHAZs. When base metal is stressed in the through-thickness, or “Z” direction, by repetitive defective weldsand necessary repairs, lamellar tearing may occur. TheEngineer should be notified of repetitive repairs.Replacement of base metal, or modifications to thedesign necessary to compensate for deficiencies createdby material discontinuities, welding, or previous repairsare to be approved by the Engineer before beginning thecorrective procedure.

C-6.6.5 When an Engineer orders NDT that was notspecified in the contract documents, the Engineer sub-jects the Contractor to additional costs for preparing theweld surfaces for NDT and for performing or arrangingfor the required NDTs to be performed. There may alsobe costs associated with delays and costs for repairs thatwould not have been required if only visual inspectionwere specified. Except as provided, the Owner is respon-sible for the cost of extra work caused by NDTs thatwere not provided for in the contract documents.

C-6.6.6 The Contractor should attempt to schedule NDTso that the QA Inspector may monitor the testing as nec-essary. However, if the QA Inspector is available infre-quently because of travel or other constraints, theContractor should not be unreasonably constrained incompleting the work. The QC and QA Inspectors, withEngineer’s approval, should agree on a schedule and sys-tem for testing and acceptance.

C-6.7 Nondestructive Testing (NDT)The NDT methods provided for in the code are radio-graphic testing, RT; ultrasonic testing, UT; magnetic par-ticle testing, MT; and penetrant testing, PT. Only RT andUT have the capability of examining the full cross sec-tion of the weld. MT and PT are methods of inspectionthat enhance visual inspection of weld and base metalsurfaces. MT may also reveal near-surface discontinui-ties. Each NDT method has advantages and disadvan-tages. Some methods of testing are expensive and requirehighly qualified technicians to perform the tests. Others


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are not expensive and do not require intensive operatortraining. RT has unique radiation safety considerations.

RT cannot be used effectively to examine corner and T-joints because restrictions on RT film placement preventcomplete examination of these joints. UT is the preferredmethod for corner and T-joints.

C-6.7.1 Groove welds in main members receive exami-nation using NDT methods. The only methods capable ofinspecting the full weld cross section are RT and UT.The NDT method required is based upon the type andloading of the joint. RT is the method selected for CJPgroove welds in butt joints with tension or reversal ofstress (alternating tension and compression) because of itssensitivity, accuracy and nature of documentation. How-ever, in corner and T-joints, RT is not reliable or cost-effective because of the configuration of the joint. UT isused for these joints because it has the capabilities of full-thickness evaluation. CJP groove welds loaded only incompression and/or shear do not have the same fatiguecharacteristics and failure would not have the same con-sequences compared to a CJP groove weld in a butt jointcarrying tension. Therefore, NDT by either RT or UTmay be used.

C-6.7.1.1 Both RT and UT are used to evaluate ESWand EGW. The large austenite grains that are common tothe weld metal produced by these weld processes makeUT sound transmission and evaluation more difficult. Thegrain boundaries may also deflect or reflect test signals. Ifthere is lack of fusion, the unwelded portion of the jointmay act as a smooth reflector 20° misaligned with theinspecting ultrasound, and cannot be evaluated by ampli-tude methods. In addition to planar discontinuities, ESWand EGW may have gross spherical porosity, or pipingporosity in the form of long tunnels, created in the solidi-fying weld metal by escaping gases. UT is not able to reli-ably detect or evaluate extensive porosity in these welds(see Table 6.4, Note 3). RT is used to supplement UT inthe evaluation of ESWs and EGWs. RT alone, however,may not detect planar flaws oriented parallel to the film ortight planar flaws, therefore the use of both RT and UTare complimentary.

C-6.7.1.2

(1) All CJP groove weld joints that are subject to ten-sile stress from design applied load are expected to betested full length by RT or UT. Butt joints carryingapplied tensile stress, per 6.7.1, are normally tested byRT, and T- and corner joints are normally tested by UT.An exception is provided for vertical butt joints in girderand beam webs, which carry predominantly shearstresses but are also subjected to tensile stress from bend-ing. For these cases, reduced testing may be used, pro-vided the portion(s) of the joint subjected to the most

tensile stress is fully tested, and the balance of the joint ispartially tested. Beginning at the tension flange, 1/6 ofthe web depth and an additional 25% of the remainder ofthe web joint are usually tested. Joints with unacceptablediscontinuities in either test portion are tested for theirentire length. The design drawings and approved shopdrawings should designate the tension flange area. If thejoint is near a point of contraflexure, both flanges mayexperience applied tension, depending upon loadingconditions.

(2) Except for longitudinal welds in butt joints (see6.7.2.1), joints using CJP groove welds and subject onlyto shear and/or compressive stress are to be tested byeither RT or UT for either 25% of the welds or 25% ofsimilar joints containing such welds. Similar joints defi-nition includes not only joint type but also those madewith a similar WPS. The default testing method is 25%of the length of each weld, however, the Contractor mayelect to examine 25% of the joints for their entire length.The length of welds tested is to be at least 25% of thetotal length of welds subjected to shear and/or compres-sion. Selecting only the shortest joints for testing wouldfail to meet the latter criteria.

If partial length testing of a weld in a compression orshear joint indicates unacceptable discontinuities, theremainder of the weld in that joint is to be tested. Weldsmade in a similar manner, using the same WPS, andmade during the same time period, could be anticipatedto have similar levels of discontinuities. Should testingindicate that a certain group of similar welds, defined bylot, contain a 20% or higher rejection rate, all jointswithin the lot are to be tested for their full length.

Longitudinal web splices are exempted from testingbecause the applied stress is low and any significant welddiscontinuities would be generally parallel to the appliedstress.

(3) Shop and field welds should be of the same qual-ity if all provisions of the code are followed, even ifmade under less favorable conditions.

C-6.7.2 Welds joining primary components in mainmembers are tested using NDT in addition to visual test-ing. CJP groove welds employ RT and/or UT per 6.7.1.PJP groove welds and fillet welds are tested using MT.However, PJP groove welds and fillets used for second-ary members need not be tested using MT.

MT is best utilized as an aid to visual inspection. Everyportion of every weld should be inspected visually whenthe weld is complete. Welds are also visually inspected be-tween passes by the welder. When visual inspection is doneproperly and thoroughly, few if any discontinuities willbe found by MT that are not visible to a skilled inspector.


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C-6.7.2.1 When spot testing is done, the inspectionlocations should be picked by the inspector at random,after welding is complete. Welds that have discontinui-ties found by this spot testing are to be tested for theirentire length, except that for welds over 3 m [9 ft] inlength, testing may be limited to 1.5 m [4.5 ft] on bothsides of the test length.

C-6.7.2.2 These high strength steels are more suscep-tible to hydrogen-induced cracking, justifying a moredetailed inspection, but caution is necessary so the MTdoes not damage the steel and create discontinuities. Theprod method of MT is, therefore, not recommended forhigh strength steels (see C-6.7.6).

C-6.7.3 Welds repaired based upon rejection by NDT arereexamined after repair. This subclause does not man-date the same test method for evaluation of the repairweld, but appropriate methods acceptable to both the QCand QA Inspector should be used. The test of the repairincludes all of the repair weld, and at least 50 mm [2 in]of the base metal on each side of the repaired area, toensure that all of the discontinuity has been removed andreplaced by sound weld metal and that no failure of theadjacent base metal or weld has occurred.

C-6.7.4 Subclause 3.7 lists general methods of repair.Weld repairs that are not routine, as described in3.7, should be performed following an approved repairWPS.

C-6.7.6 Dry powder methods of MT are best for generalsteel fabrication. Tests can be performed without stain-ing the steel with solutions, and testing will not interferewith the continuation of welding. Steel surfaces are to beclean and relatively smooth so tests can be accuratelyperformed by either the prod or yoke method. Whenthere are distinct lines in the surfaces or fusion bound-aries of welds, such as weld toes or edges of mill scale,the iron powder indicating medium may become trappedin the surface depression, making it difficult to distin-guish an indication of an unacceptable discontinuity fromfalse indications caused by innocuous surface discontinu-ities acceptable under the code.

The prod method of MT requires large electrical currentsto be conducted through the steel. The flow of current inthe steel creates a magnetic field that will cause magneticparticles (iron powder) to outline discontinuities thatinterrupt the magnetic lines of flux. Magnetic lines offlux are normal to the flow of current in the prod methodof MT. In the yoke method of MT, an electromagnet isused to generate the required magnetic field. Magneticlines of flux flow along the surface and in the surface ofparts being inspected directly between the poles of theelectromagnet yoke, causing magnetic particles to out-

line discontinuities in the surface. Yoke equipment isgenerally more portable and less expensive.

Although the equipment orientation may vary, there is nodifference between the MT indication produced by theprod or yoke methods. Both methods of inspection arebased upon the visual acceptance standards of 6.26. Ade-quate illumination of the tested area is critical to allowevaluation of particle patterns. The QC and QA Inspec-tors need to be satisfied with the methods and effective-ness of lighting, especially for congested or obstructedareas.

C-6.7.6.1

(1) Copper prods are not allowed on steels with aminimum specified yield strength of 345 MPa [50 ksi] orgreater because these steels are more hardenable, andthere is also a risk that copper melted by arcing of theprods can migrate into the steel along grain boundariesand cause cracking. Aluminum prods are specified toavoid the problems of copper, but still require careful useto avoid arcing. Aluminum prods build up a surfaceoxide that interferes with the necessary electrical contact,therefore frequent cleaning is necessary. Steel prodshave been reported to provide good results with reducedarcing, but rust needs to be periodically removed and therounded ends maintained to ensure good contact at vari-ous angles of use.

(2) Arcing may be reduced by keeping the prodsclean and by cleaning surfaces prior to testing. Bestresults are obtained when testing is performed on sur-faces free of mill scale. High current is required foreffective testing, but current demand may be reduced bysmaller prod spacing. Arcing is reduced or eliminatedwhen good electrical contact is established before theequipment is energized. Good prod pressure is essentialto achieve good electrical contact.

C-6.7.6.2

(1) DC power is often specified because it has theability to detect discontinuities that are slightly below thesurface. However, many operators prefer AC power andconsider it more effective for surface inspection.

(2) The lifting force that is specified is a measure ofthe effectiveness of the power of the magnet. When thelifting force is less than that specified, the inspectingmagnetic field is proportionately weaker. When ACpower is used, the lifting force is less, but the iron powderparticles are more mobile due to the continuous 60 MHzchange in polarity.

C-6.7.6.3 Surfaces are to be clean and dry so thatthere will be no interference with MT (iron powder) indi-cator mobility. The contact surface allows transmission of


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current in the prod method and magnetic lines of flux inthe yoke method. Magnetic lines of flux can penetrate thin(1 mil to 2 mils) layers of nonconductive coatings such aspaint, and this can be verified with the lift text in 6.7.6.2.

C-6.7.6.4 MT inspection is most sensitive to disconti-nuities that interrupt the magnetic lines of force. If thelines of force are parallel to the discontinuity, the discon-tinuity may be missed. Yoke or prod position and orienta-tion during testing is critical. One of the more serioustypes of bridge fillet weld discontinuities is transversecracking in longitudinal web-to-flange welds. These cracksmay appear at regular intervals along the length of theweld. Sometimes called shrinkage cracks, these are bestdetected by placing the prods on the steel normal to thelongitudinal axis of the weld. When using the yokemethod, the yoke magnetic poles or feet are placed asclose to the weld as possible, almost directly on the weld,parallel to the longitudinal axis. The yoke feet are usuallytoo large to allow the yoke to be placed directly on theweld without first making edge contact with the weband flange. The yoke needs good areas of contact to beeffective.

Welds are examined in a manner that will reveal all sig-nificant discontinuities. Complete MT requires overlap-ping test positions with the test equipment oriented bothparallel and transverse to the axis of the member at eachtest site. Discontinuities are best detected when their axisis normal to the magnetic lines of force. Therefore, theprod technique is most sensitive to discontinuities whosemajor axis is parallel to a line drawn between the twoprods, whereas the yoke technique is most sensitive todiscontinuities whose major access is normal to a linedrawn between the two poles.

C-6.7.6.5 Thorough reporting of test conditions andresults provides proper documentation that welds havebeen properly tested and meet contract requirements.

C-6.7.7 PT may be used under some conditions. It is asimple test method and is inexpensive for localized tests ofsmooth surfaces. When more extensive testing is required,PT may become more expensive than MT because of longdwell times, surface preparation, testing materials cost, andcleanup requirements. It requires clean, smooth surfaces toproduce accurate test results.

There is no general requirement for PT in the code. Thismethod of inspection may be used to aid visual inspec-tion, and to detect and define the extent of discontinuitiesopen to the surface. The size of the indication is notindicative of discontinuity size. The size of discontinui-ties discovered by PT should be determined by visualinspection aided by careful excavation, if necessary, afterthe inspecting medium has been removed.

Part BRadiographic Testing of

Groove Welds in Butt Joints

C-6.8 Extent of TestingWhen RT is required by code, the minimum amount oftesting required is provided in 6.7. Additional RT may bespecified by the Engineer in the contract documents (seeC-6.6.5).

C-6.9.1 The procedures and standards set forth in thissubclause are primarily designed for the RT inspection ofCJP groove welds in butt joints in bridges. Typicalgeometries for structural connections and design require-ments for these structures were considered. An effortwas made to incorporate ASTM standards and utilize theprocedures of the ASME Boiler and Pressure VesselCode whenever possible.

C-6.9.2 Because this subclause does not address RT ofall possible configurations of welds and joints in bridgestructures, variations are allowed with the agreement ofthe Contractor and Engineer. Variations are also allowedfor proven innovations in RT technology that have notyet been adopted into the code.

C-6.10.1 The single source of inspecting radiation isspecified to avoid confusion or blurring of the RT image.Subclause 6.10.5 contains limits on the size and place-ment of the source to limit geometric unsharpness. RTsensitivity and sharpness is judged solely on the qualityof the image quality indicator (IQI) image(s).

C-6.10.2 Ionizing radiation and chemicals used in RTmay present serious health hazards, so safety regulationsneed to be rigorously followed.

C-6.10.3 If the Engineer will require weld surfaces nototherwise specified to be ground flush or otherwisesmoothed (see 3.6) to be profiled in preparation for RT,this should be specified in the contract documents. TheEngineer and the Contractor should agree in advance onwhich weld surface irregularities need not be ground,unless surface irregularities interfere with the interpreta-tion of the radiograph. It is difficult and sometimesimpossible to distinguish internal discontinuities fromsurface discontinuities when reviewing radiographs inthe absence of information describing the weld surface.

C-6.10.3.1 Weld tabs are removed prior to RT inspec-tion so that the radiograph will examine the welds as fin-ished and placed in service. Contraction cracks, difficultto identify in a radiograph, may occur in the weld at theinterface between weld tabs and the edge of the plate orshape joined by the weld. For certain welds or joints,


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such as when plate edges will be subsequently removedduring cutting of web camber or multiple flanges, theEngineer may waive the requirement to remove weldtabs.

C-6.10.3.2 Steel backing is removed when requiredby 3.13.2, or may remain in place when allowed by3.13.2 or 3.13.2.2. When removed, the remaining weldsurface and adjacent steel affected by the removal areground smooth and flush (see C-3.6.3). Tack weldsbetween backing remaining in place and base metal aresubject to the requirements of the applicable provisionsof 3.3.7.

RT is performed following any required removal ofbacking so that the radiograph will examine the welds asfinished and placed in service.

C-6.10.3.3 When weld reinforcement and/or backingis not removed, shims placed under the image qualityindicators (IQIs) are used so that the IQI image may beevaluated on the average total thickness of steel (weldmetal, backing, reinforcement) exposed to the inspectingradiation.

C-6.10.4 The provisions of this subclause are to providefine grain film and to avoid coarseness in the image thatmay result from the use of fluorescent screens.

C-6.10.5 To avoid as much geometric distortion as possi-ble, the source of radiation is centered with respect to theportion of the weld being examined.

C-6.10.5.1 This subclause is provided to limit geo-metric unsharpness, which causes distortion and blurringof the RT image.

C-6.10.5.2 and C-6.10.5.3 These subclauses areintended to limit geometric distortion of the object asshown in the radiograph.

C-6.10.6 This subclause provides that X-ray units, 600 kvpmaximum, and iridium 192 sources may be used for allRT, provided these have adequate penetrating ability andcan produce acceptable radiographic sensitivity basedupon IQI image as provided in 6.10.7. Since cobalt 60produces poor RT contrast in materials of limited thick-ness, it is not approved as a RT source when the thick-ness of steel being radiographed is 75 mm [3 in] or less.When the thickness of steel being radiographed exceeds75 mm [3 in], cobalt 60 is often preferred for its penetrat-ing ability.

Care should be taken to ensure that the effective size ofthe radiograph source is small enough to preclude exces-sive geometric unsharpness. Geometric unsharpness isdefined as the fuzziness or lack of definition in a radio-graphic image resulting from the source size, object-to-

film distance, and source-to-object distance. Geometricunsharpness may be expressed mathematically as:

where Ug is the geometric unsharpness, F is the size ofthe focal spot or gamma radiation, Li is the source-to-film distance, and Lo is the source-to-object distance.

C-6.10.7 Since RT sensitivity and the acceptability ofradiographs is judged using the image of the requiredIQIs, care is taken in describing the manufacture and useof the required IQIs. IQIs are placed near the extremitiesof weld joints where geometric distortion will contributeto lack of sensitivity in the radiograph.

C-6.10.7.1 IQIs may be placed only on the source sideunless otherwise approved by the Engineer. Failure toplace the IQIs on the source side during the RT exposure,without prior approval of the Engineer, is cause for rejec-tion of the radiographs.

C-6.10.7.2 The IQI thickness is to be as specified. AnIQI with a smaller essential hole or thinner wire size maybe used at the Contractor’s option. These IQIs requiregreater sensitivity.

C-6.10.7.3 The IQI selected using Table 6.1 or 6.1Ais based upon either thickness T1 or T2.

C-6.10.7.4 Figure 6.1E provides general dimensionalinformation for hole-type IQIs. ASTM E 1025 governsthe manufacture of hole-type IQIs.

C-6.10.7.5 Figure 6.1F provides general dimensionalinformation for wire IQIs. ASTM E 747 governs themanufacture of wire IQIs.

C-6.10.8 Welds are radiographed and the film indexedby methods that will ensure complete, continuousinspection of the weld within the limits specified.Flange-to-flange welded butt joints that join segments ofthick flanges in beams and girders are particularly diffi-cult to radiograph because of geometric distortion andundercut from scattered radiation at the ends of the weldthat represent the flange edges. Weld discontinuities atthese critical locations are limited under the provisions of6.26.1.2. Centering of the source close to the flange edgewill avoid geometric distortion at the edge of plate. Theuse of “edge blocks” will help to allow RT evaluation ofthe edge, since all radiation will still pass through solidmetal within the area of interest.

C-6.10.8.1 Because of dimensional limits and distor-tion, it may be necessary to make multiple exposures toexamine longer welds. Several films of standard lengthsto radiograph longer welds may also be used when a sin-gle source exposure is taken, provided IQIs on each film

UgF Li Lo–( )

Lo-------------------------–


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indicate acceptable image sharpness is maintained. Longerwelds may also be radiographed with multiple exposuresand several films.

C-6.10.8.2 Backscattered radiation can cause generalfogging and produce artifacts in the radiograph. Themethod described in this subclause will identify back-scattered radiation so that corrective steps can be taken.

C-6.10.9 RT is designed to inspect all of the weld zone.Film widths need to be sufficient to inspect all portionsof the weld joint and have sufficient room for weldidentification.

C-6.10.10 Quality radiographs imaged and processedwith the appropriate IQI sensitivity are necessary forproper RT. Defective radiographs are not acceptable.

C-6.10.10.1 Blemishes are film defects that, ifallowed, would obscure actual discontinuities indicationsor provide false indications in areas of interest on thefilm.

C-6.10.10.2 Faulty techniques may cause indicationsto be missed or false indications to be created.

C-6.10.11 To avoid the necessity of making multipleexposure or using films of more than one exposure speed,radiographic films within the full limits of useful filmdensity may be used. In general, within the limits ofdensity approved by the code, the greater the film density,the greater the radiographic sensitivity.

C-6.10.11.1 The calculation method for determiningthe film density is given. Light intensity is measured inconformance with the methods in ASTM E 1742.

C-6.10.11.2 The weld transitions in thickness pro-vided for this subclause are expected to be gradual with amaximum slope of 1:2.5 as shown in Figure 6.4. Forlarge transitions, the film density should be establishedfor the thinner material. The film density for the thickermaterial is allowed to be below that required in 6.10.11,unless otherwise required.

C-6.10.12 Information needs to uniquely identify theradiograph and match the radiograph to the weld joint.Radiograph identification marks and location identifica-tion marks are used to locate discontinuities requiringrepair, allow repairs to be made without repetitive orunnecessarily large excavations, and to verify that dis-continuities have been repaired as demonstrated by thesubsequent repair radiograph. Permanent indications onthe steel such as punch-marks, numbers and lettersshould be minimized, limited to those needed to locatethe film’s position. All such marks should be made withlow-stress or mini-stress stamps.

C-6.10.13 The information provided on the radiographensures traceability and control of the RT.

C-6.10.14 Edge Blocks. Flange-to-flange welded buttjoints that join segments of thick flanges in beams andgirders are particularly difficult to radiograph due to geo-metric distortion and undercut from scattered radiation atthe ends of the weld that represent the flange edges.Weld discontinuities at these critical locations are limitedunder the provisions of code.

On weldments over 12 mm [1/2 in] in thickness, it wasdemonstrated by using drilled holes and lead indicatorsnear the top edge of a weldment that a substantial portionof this edge was over exposed and could not be shown,which left the possibility of not showing discontinuities.By using edge blocks and a standard source alignment, leadindicators and drilled holes could be shown on a radio-graph at the plate edge.

C-6.11 Acceptability of Welds

The provisions of 6.26.1.2 prescribe the quality of weldsradiographed for bridge structures.

C-6.12 Examination, Report, and Disposition of Radiographs

C-6.12.1 A suitable variable intensity illuminator withspot review or masked spot review capability is requiredfor more accurate film viewing with the viewers’ eyesshielded from the portions not under examination. Theability to adjust the light intensity reduces eye discomfortand enhances the visibility of film discontinuities. Sub-dued light in the viewing area allows the reviewer’s eyesto adjust so that small discontinuities in the radiographicimage can be seen. Film review in complete darkness isnot advisable because the contrast between darkness andthe intense light from portions of the radiograph with lowdensity cause discomfort and loss of accuracy. Theviewer should properly illuminate radiographs with den-sities up to the maximum allowed film density of 4.0.

C-6.12.2 After the Contractor’s RT technician hasreviewed and approved both the radiographs and thereport interpreting them, the radiographic examinationfilm and report are submitted to the QA Inspector for aseparate review. All radiographs, including those showingunacceptable quality prior to repair, need to be available tothe QA Inspector.


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C-6.12.3 The Contractor delivers a full set of radiographsand reports to the Owner unless declined in writing by theOwner. If not taken by the Owner, the Contractor main-tains these records for a period not less than one yearafter completing the project, unless the Owner provideswritten authorization to discard them.

The term “a full set of radiographs” means one radio-graph of acceptable quality from each radiographic expo-sure required for complete radiographic inspection,including radiographs showing discontinuities that weresubsequently repaired and re-radiographed. If the Con-tractor elects to load more than one film in each cassetteto produce an extra radiograph for the Contractor’s ownuse, or to avoid possible delays caused by film artifactsor false indications, or both, the extra radiographs, unlessotherwise specified, are the property of the Contractor.

Part CUltrasonic Testing of Groove Welds

C-6.13.1 The ultrasonic testing (UT) provisions are adirect method for testing weldments, designed to ensurereproducibility of test results when examining specificreflectors. Most CJP groove welds within the range ofthe thickness given may be satisfactorily tested using theprovisions of Clause 6, Part C.

C-6.13.2 Variations to standard UT procedures asdescribed in this code are allowed with the approval ofthe Engineer. Such variations may be needed because ofunusual joint geometries, thicknesses less than 8 mm[5/16 in] or more than 200 mm [8 in], other unusualapplications, or the use of new or innovative techniquesor equipment.

During routine fabrication of structural steel, all weldsshould be inspected and accepted by QC prior to beingcoated. Where coated surfaces are to be tested, the condi-tion of the test surface should be considered before rou-tine testing is done, including measurement andreporting. Although the code prohibits routine UTthrough coatings, a good, tight, uniform coating may notinterfere with the application of UT. The Engineer’sapproval is required for UT through any coating. Calibra-tion of transducers and UT systems on similarly coatedspecimens may be help identify attenuation or other fac-tors caused by the coating.

C-6.13.3 The code requires that RT be used as a supple-ment to UT when examining ESW and EGW weldsbecause of the inability of UT to accurately evaluateporosity on an amplitude basis. Piping porosity in this

type of weld, although appearing cylindrical, usually hasa series of cascaded surfaces throughout its length. TheUT reflectivity of these cascaded surfaces does not gen-erally correspond to a straight line reflector such as thatexpected from a side-drilled hole, itself a difficult dis-continuity to quantify.

Piping porosity often responds to UT like a series of sin-gle point reflectors, as if received from a line of sphericalreflectors. This results in a low amplitude-responsereflecting surface, resulting in a trace that has no reliablerelationship to diameter and length of this particular typeof discontinuity.

In addition to this problem, the general nature of pipingporosity in conventional ESW and EGW welds is usuallysuch that holes in the central portion of the weld may bemasked by other surrounding holes. The branches or tun-nels of piping porosity have a tendency to tail out towardthe edges of the weld nugget. UT can only effectivelyevaluate the first major reflector intercepted by the soundpath (see Note 4 of Table 6.4). No mention of additionalRT is presently made with reference to testing ESW andEGW welds in Table 6.3, since these processes are notallowed for tension welds.

C-6.13.4 The provisions of Clause 6, Part C have beendeveloped for the testing of welded joints. Base metaltesting should be as described in AASHTO M270M[M270] (ASTM A 709M [A 709]).

Base metal cracks and other discontinuities discoveredby UT are included in the report to the Engineer.

C-6.14.1 The required amount of testing to be performedis as described in 6.7.

C-6.14.2 Proper UT inspection requires knowledge ofthe joint and base metal configuration and the weldingprocess used. Based upon this information, the orienta-tion, location, and nature of probable discontinuities canbe established. The testing angles described in Table 6.2are based upon the thickness and joint configuration,with special requirements for welds made by EGW orESW.

C-6.15 Ultrasonic EquipmentStandards are established for UT flaw detectors to ensureadequate mechanical and electrical performance whenused in conformance with the requirements of the code.

Subclauses 6.15.1 through 6.15.5 cover the specificequipment features considered for equipment qualification.Subclauses 6.15.6 through 6.15.7.7 cover the dimen-sional and performance requirements for transducers.


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C-6.15.7.2 Transducer size and shape is limited toreduce the scatter in the results of discontinuity evalua-tion, thought to be attributed to transducer size. Roundtransducers are not acceptable for angle beam testing.

C-6.16.1 Reference blocks are used for the calibrationand certification of equipment.

C-6.16.2 The code prohibits the use of square corners forcalibration purposes because of the inability of acquiringamplitude standardization from various corners that arecalled “square.” Factors that may affect amplitude stan-dardization are: the size of the fillet or chamfer on thecorner, if any; the amount the corner is out of square(variation from 90°); and surface finish of the material.When a 60° probe is used, it is very difficult to identifythe indication from the corner due to high amplitudewave mode conversions occurring at the corner.

C-6.16.3 The RC resolution block shown in Figure 6.4Bis used to verify the ability of the equipment, includingthe UT instrument, cable and transducer as a combina-tion, to distinguish and provide measurement for each ofthe three holes provided for the given search angle.

C-6.17.1 The use of ASTM E 317 for horizontal linearityqualification has been eliminated and a step-by-step pro-cedure outlined in 6.22.1 is used for certification.

C-6.17.2 The vertical linearity of the UT unit is calibratedat intervals not exceeding two months by the proceduredescribed in 6.22.2 to verify continued accuracy. Certifi-cation is maintained with use of information tabulated ona form similar to Annex F, Form F-1 (example informa-tion is also shown).

Caution is to be used in the application of alternate meth-ods for vertical linearity certification. Normal ways oftranslating voltage ratios to dB graduations generallycannot be used due to potentiometer loading and capaci-tance problems created by the high frequency currenttransfer. A high degree of shielding will also be main-tained in all wiring.

C-6.17.3 Internal reflections may provide false indi-cations of discontinuities or distort the decibel rating ofreflected sound. Transducers are checked after 40 hoursof use.

C-6.17.4 Because the contact surfaces of search unitswear and cause loss of indication location accuracy, thecode requires accuracy checks of the search unit after amaximum of eight hours use. The responsibility forchecking the accuracy of the search unit after this timeinterval is placed on the individual Level II performingthe work.

C-6.18 Calibration for Testing

The requirements for calibration of the test equipmentjust prior to and during testing are provided in 6.18.1through 6.18.5.

C-6.18.4.1 Indications of at least two plate thick-nesses is be displayed in order to ensure proper distancecalibration, because the initial pulse location may beincorrect due to a time delay between the transducercrystal face and the search unit face.

C-6.18.5.1 The horizontal location of all screen indi-cations is based on the locations at which the left side ofthe trace deflection breaks the horizontal base line. Theinitial pulse location will always be off to the left of thezero point on the display. Care is to be taken to ensurethat the pulse at the left side of the screen is the initialpulse and not one from a reference reflector. Verify byremoving search unit from workpiece.

C-6.19.1 The material needs to be marked in a suitablemanner to allow for measurement, calculation, and record-ing of flaw indications. The scales provided also allow forthe calculation of flaw location based upon the accuratelocation of the transducer(s).

C-6.19.3 The surfaces on which the transducer is placedare to be free of any materials which will interrupt, dis-turb or distort the transmission of sound. Weld spatter,dirt and loose mill scale will prohibit free scanningmovement and the intimate contact of transducer andsteel, with resultant loss of sound transmission andreception. Grease, oil, and coatings, in addition to possi-ble loss of contact, may distort the directionality of thesound path and weaken both sound transmission andreception (see 6.13.2 for testing through coatings and theuse of nonlisted couplants).

C-6.19.4 It is recognized that couplants other than thosespecifically allowed in the code may work equally wellor better for some applications. It is beyond the scope ofthe code to list all fluids and greases that could be accept-able couplant materials. Any couplant material, otherthan those described in the code, that has demonstratedits capability of performing to code requirements, maybe used in inspection upon agreement between the Engi-neer and the UT inspector (see 6.13.2).

Tests should be conducted to quantify variations in theresponse from the reference reflector caused by differ-ences between the couplants used for calibration and foractual testing. Glycerine will give different values thancellulose gum. Any measurable difference should betaken into account in discontinuity evaluation.


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C-6.19.5 The provision to search the base metal for lam-inar reflectors is not intended as a check of the accept-ability of the base metal, but rather to determine theability of the base metal to accept specified UT proce-dures (see 6.13.4).

C-6.19.5.1 A procedure for size evaluation of laminarand lamellar flaws is provided in 6.23.1.

C-6.19.5.2 Grinding the weld surface or surfacesflush may be necessary to obtain geometric accessibilityfor alternate UT procedures when laminar discontinuitiesin the base metal prohibit testing using standard proce-dures. Contract documents may require flush grinding oftension groove welds to improve fatigue performanceand to facilitate more accurate RT and UT.

C-6.19.6 When required by Tables 6.3 and 6.4 as appli-cable, the sensitivity for evaluation of discontinuities isincreased by at least four decibels above the maximumsensitivity required to produce reference level ampli-tudes from a flaw of maximum size (reflection ampli-tude) if detected at the maximum testing sound path.This increased sensitivity assures that unacceptable discon-tinuities are not missed as a result of planar-type disconti-nuities at the fusion boundary.

C-6.19.6.1 UT under the code is performed followingspecific procedures to provide standard results andrepeatability between UT technicians. The UT techniciandoes not normally deviate from the given procedureswithout approval by the Engineer. The procedures asprovided are integral with the specified transducers andthe acceptance criteria of Tables 6.3 and 6.4. A change inprocedure or transducer necessitates a change in theacceptance criteria of Tables 6.3 and 6.4. Use of otherangles or weld faces may result in a more or less criticalexamination than established by the code.

Table 6.2 was established on the basis of a searchunit angle of 70°. This angle will best detect and moreaccurately evaluate discontinuities having a majordimension oriented normal or near normal to the com-bined residual and applied tensile stresses, consideredmost detrimental to weld integrity. Conservativelyassuming that all discontinuities could be oriented in thisdirection, the 70° probe should be used whenever possi-ble. For optimum results, a 250 mm [10 in] sound pathdistance has been established as maximum for standardtesting. However, there may be some joint sizes and con-figurations that require longer sound paths to inspect theweld completely.

Testing procedures 6, 8, 9, 12, 14, and 15 in the proce-dure legend of Table 6.2, identified by the top quarterdesignation GA or the bottom quarter designation GB,require evaluation of discontinuities directly beneath the

search unit, necessitating a ground weld surface. Moreaccurate results may be obtained by testing these largewelds from both Face A and Face B.

The procedure chart was developed considering theabove factors. Note 5 of Table 6.2 provides that disconti-nuities in tension welds in bridges are not evaluateddirectly beneath the search unit, but by passing sounddirected from the opposite side of the joint.

The pitch-and-catch technique for UT evaluation ofincomplete fusion in ESW and EGW joints is intended asa secondary test of the area along the original grooveface in the middle half of the plate thickness. This testmay be specified to further evaluate an UT indication inthis area which appears on the display at scanning levelbut is not rejectable by indication rating. The expectedpitch-catch amplitude response from such a reflector isvery high, making it unnecessary to use the applicableamplitude acceptance levels. However, since no alter-native is provided, these decibel ratings are used. Sinceonly a specific location is being evaluated, predeter-mined positioning of the probe can be made. Probe-holding fixtures are most helpful in this operation.

The use of the 70° probe in the primary application isadequate in testing ESW and EGW fusion surfaces ofmaterial 65 mm [2-5/8 in] and less in thickness becauseacceptance levels are such that proper evaluation can beexpected.

Legend “P.” Because of the high energy loss that is pos-sible due to wave mode conversion, the use of 60° probesis prohibited for evaluation when using the pitch-and-catch method of testing.

C-6.19.6.2 Access for butt joints is provided fromboth sides, whereas T- and corner joints may have lim-ited access. Because the nature of butt joints is often crit-ical to overall structural performance, butt joint quality isverified by examination from both sides of the joint.

Although discontinuity characteristics and orientation areroutinely assumed for a given joint design, UT of theentire weld using intersecting sound paths is required,whenever possible, to detect any flaws that may bepresent in locations or orientations other than thoseassumed.

C-6.19.6.3 The procedure provided is to ensure evalu-ation of all discontinuities that may appear on thedisplay.

C-6.19.6.4 The attenuation rate of two decibels per25 mm [1 in] of sound travel, excluding the first 25 mm[1 in], is established to provide for the attenuation(absorption) of sound energy in the test material. Thesound path distance used is the dimension on the display.


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The rounding of numbers to the nearest decibel is accom-plished by maintaining the fractional or decimal valuesthroughout the calculation, and at the final step, advanc-ing to the nearest whole decibel value when values ofone-half decibel or more are calculated, or by droppingthe part of the decibel less than one-half.

C-6.19.6.5 Gain is the adjustment to increase instru-ment sensitivity. Attenuation is the downward adjust-ment of instrument sensitivity. The type of instrumentadjustment system used affects the method for calculat-ing the indication rating.

C-6.19.7 The required six decibel drop in sound energymay be determined by adding six decibels of gain to theindication level with the calibrated gain control, and thenrescanning the weld area until the amplitude of the dis-continuity indication drops back to the reference line.

When evaluating the length of a discontinuity that doesnot have equal reflectivity over its full length, its lengthevaluation may be misinterpreted. When a six decibelvariation in amplitude is obtained by probe movement,and the indication rating is greater than that of a minorreflector, the operator should record each portion of thediscontinuity that varies by ±6 dB as a separate disconti-nuity to determine whether it is acceptable under thecode based on length, location, and spacing.

C-6.19.8 In the procedures specified for UT testing, thezero reference level for discontinuity evaluation is to bethe reference level established during calibration for anindication reflected from a 1.5 mm [1/16 in] diameterhole in the IIW ultrasonic reference block. When actualtesting of welds is performed, the minimum acceptablelevels are given in decibels for various weld thicknesses.The minimum acceptance level is provided in Table 6.3or Table 6.4, as applicable. In general, the higher theindication rating or acceptance level, the smaller thecross-sectional area of the discontinuity normal to theapplied stress in the weld.

Indication ratings up to 6 dB more sensitive than reject-able need to be recorded on the test report for welds des-ignated as being “Fracture Critical” so that future testing,if performed, may determine if there is flaw growth. TheUT acceptance criteria are identical for welds in fracturecritical regions and nonfracture critical welds.

C-6.19.9 Welds containing unacceptable discontinuitiesshould be physically marked directly on or adjacent tothe weld to identify the location and extent of the flaw.The depth of the discontinuity is noted nearby on thesteel. This enables the repair to be performed at thelocation of the discontinuity, rather than excavating anentire region attempting to find the discontinuity. Weld-ing personnel may not be able to interpret the UT tech-

nician’s report to determine the location and nature of thediscontinuity.

C-6.19.9.1 Following repair, the results of the test ofthe repaired region are placed on the previous reportform, with the designator “R1” added to indicate that arepair has been made. Subsequent repairs to the samediscontinuity within the joint would receive a designa-tion such as R2, R3, and so forth. Use of the same formfor the original weld and all repairs improves control ofthe documentation of the testing, as well as providesrecords of unrepaired regions that may be subsequentlyinspected following repairs in adjacent areas.

C-6.19.9.2 Welds containing a large number ofrecordable indications, with subsequent repairs, may fillan existing UT report form. Additional new forms, tieddirectly to the previous report through a numbering sys-tem, may be used.

C-6.19.10 Welds rejected using the UT criteria of Tables6.3 or 6.4, as applicable, may be repaired using the meth-ods described in 3.7, unless replacement is selected bythe Contractor in conformance with 3.7.2. The repairedor replaced weld should be inspected using the same cri-teria as the previous weld, reported on the same reportform or on an additional report form in conformancewith 6.19.9.

C-6.20.1 All welds subjected to UT should have a reportshowing the results. For welds that are acceptable with-out repair, testing information is not required regardingany acceptable indications. The report for an acceptableweld need only provide the weld identification, a state-ment of acceptance, and the Inspector’s signature.

C-6.20.2 After the Contractor’s UT inspection technicianhas reviewed and approved the UT report, the reportis submitted to the QA Inspector for a separate review.All reports, including those showing unacceptablequality prior to repair, should be reviewed by the QAInspector.

C-6.20.3 The term “a full set of completed report forms”means one report for each weld inspected by UT,whether the weld was accepted, rejected and repaired, orreplaced. Should entire assemblies be replaced, submittalof UT reports for the piece replaced need not be submit-ted. The Contractor need not retain copies of the formsonce the full set is provided to the Owner, nor retaincopies after one year following completion of the projectshould the Owner waive the requirement for submittalof the UT reports. The Contractor should not discardreports until the Owner has acknowledged receipt ofwritten notice regarding planned UT report disposal.


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C-6.21 Calibration of the Ultrasonic Unit with IIW or Other Approved Reference Blocks

The procedures for the calibration of the UT search unitsusing calibration blocks is provided in this subclause.The reference standards for the calibration blocks areprovided in 6.16. The frequency of testing of search unitsis described in 6.17.3 and 6.17.4.

C-6.22.1 Equipment Qualification Procedures. Theprocedures for the qualification of the UT equipment isprovided in this subclause. It is performed using a stan-dard straight beam search unit meeting the requirementsof 6.15.6 on IIW or DS calibration blocks as referencedin 6.16. The frequency of equipment calibration isdescribed in 6.17. Since this qualification procedure isperformed with a straight beam search unit which pro-duces longitudinal wave with a sound velocity of almostdouble that of shear wave, it is necessary to double theshear wave distance ranges to be used in applying thisprocedure. Example: The use of a 250 mm [10 in] screencalibration in shear wave would require a 500 mm [20 in]screen calibration for this qualification procedure.

C-6.23.1 Straight (Longitudinal) Beam Testing. Thetechnique described provides a consistent method fordetermining the location and length of both large andsmall discontinuities when using a straight beam transducer.

C-6.23.2 Angle Beam (Shear) Testing. When usingangle beam testing to determine acceptance of weldsusing Tables 6.3 or 6.4, the length of the discontinuity ismeasured if the reflection exceeds the limits of a Class Ddiscontinuity, which is acceptable regardless of length.The technique described provides a consistent methodfor determining the location and length of discontinuitieswhen using an angle beam transducer.

C-6.24 Scanning Patterns

The use of the scanning patterns of this subclause pro-vide standardized approaches to evaluate the full thick-ness and width of the weld, with patterns applied fromboth sides of the joint when possible to produce soundfrom crossing directions. The use of a particular scan-ning pattern for a particular weld is not described bycode, rather the scanning pattern should be selected bythe UT technician based upon the orientation of theanticipated discontinuity.

For ESW and EGW welds, see Legend “P” in Table 6.2.

C-6.25 Examples of dB Accuracy Certification

The decibel dB accuracy procedure as described in6.22.2 is complex. The use of the example in Annex F,Part B is available to assist the user of the code in theapplication of this procedure.

C-6.26.1 Visual Inspection. All welds are required to bevisually inspected. Visual inspection is performed beforewelding, during welding, and after welding, as necessaryto ensure that the requirements of the Contract Docu-ments are met and that all welds conform to the visualrequirements of this subclause. The Inspector is notrequired to inspect each weld pass, but periodicallyobserve welding with sufficient frequency to verify theskills of the welder, proper joint preparation, WPS vari-ables, and the visual quality of typical root, intermediate,and final weld passes. In addition to inspection beforeand during welding, the Inspector is expected to visuallyinspect every completed weld to verify conformance tothese requirements (see C-6.5).

Each welder, welding operator, and tack welder shouldbe a visual inspector of his or her own work. Weldingpersonnel should know when welds display visual dis-continuities not acceptable under the code. Because eachweld pass of every weld is to be inspected by the welder,and the inspector monitors welding in progress andmakes a detailed inspection of completed welds, majorweld defects or gross nonconformance to the code shouldbe detected.

Welds are considered to be visually acceptable if theycomply with the requirements of this section. Because itmay not be remedied by a subsequent pass, any crack orother significant defect in any weld pass makes the weldunacceptable and requires repair or replacement of theweld. Such defects can often be seen by the welder orinspector. If the initial weld pass or any subsequent weldpass is visually unacceptable, the welder should not con-tinue to weld and cover the defect with the deposition ofadditional weld metal.

Small discontinuities may not be visible to the welder orthe inspector during or after welding. Discontinuitiesundetectable by visual inspection (VT), or smaller thanthe standards described in this subclause, are acceptable.All welds are required to be visually inspected andaccepted by visual criteria before being subjected toother required nondestructive testing. Nondestructivetesting, particularly RT and UT procedures that have theability to inspect the complete weld volume after theweld is completed, may find small discontinuities thatare acceptable to visual standards, but not acceptable toRT or UT standards.


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C-6.26.1.1 Cracks. Cracks are not allowed even ifsubsequent weld passes will cover them or if located inan exclusively compression area. Cracks are prohibitedbecause they are sharp planar defects that concentratestress. Cracks in tension zones of bridge members can beexpected to grow by fatigue, provided the stress leveland number of stress cycles is sufficient. They may growto critical size and cause brittle fracture if not discoveredand repaired.

There are three main types of cracks. “Hot” cracks formupon solidification and are generally confined to individ-ual weld passes in single and multipass welds. “Cold”cracks are caused by hydrogen and occur after weldsolidification is complete. Fatigue cracks generally takeyears to form as a result of concentrations of stress at theweld metal or base metal adjacent to weld defects,notches, or design details.

Except for ESW and EGW, solidification “hot” cracks inall welds should be discovered when the welding slag isremoved. They are generally limited to individual weldpasses, although they may coalesce to form larger cracks.Hot cracks are usually longitudinal cracks in the centerof the weld pass. Since the last part to solidify in an ESWand EGW joint is the center of the single-pass weld nug-get, hot cracks in these welds are generally confined tothe center of the weld and do not show at a surface. RTor UT is used to inspect for the presence of hot cracks inelectroslag and electrogas welds.

Cold cracks are generally discovered after the weld hasbeen allowed to cool and has been at ambient tempera-ture for several hours or days. Cold cracking is mostcommon when partially completed welds have cooleddown before there is adequate time to diffuse hydrogenfrom the weld and HAZ. Cold cracks can be found inboth completed and uncompleted welds, provided theweld region has cooled sufficiently to allow the cracks toform. Hydrogen-assisted cracking does not occur whilethe weld region remains at elevated temperatures. Whilehydrogen-assisted cracks can be found in the weld orHAZ, and may be parallel or transverse to the directionof welding, they commonly occur near the fusion bound-ary of the weld and base metal. They are typically thecause of underbead cracking. Cold cracks are more likelyto occur under conditions of high restraint.

Both hot and cold cracks may be discovered in the rootpass because of the high restraint stresses that are presentat that location, and as a result of the rapid cooling that isoften associated with the first pass. Hot cracks in the rootpass may simply mean the first pass was not largeenough to sustain the restraint stress, or may have had animproper width to depth ratio. Cold cracks should notoccur if welding conditions avoid introducing hydrogen

into the weld zone and proper preheat and interpass tem-peratures are provided (see C-4.2).

C-6.26.1.2 Fusion. To achieve effective stress trans-fer, sound fusion is essential between the weld metal andall joint surfaces, and between each weld pass and previ-ous weld passes.

C-6.26.1.3 Craters. When weld craters are not filled,a surface shrinkage condition is created that may causecrater cracking. Welds should be full size and of theproper cross section to ensure that the weld is sound, hasthe required strength, and has produced an HAZ that willnot crack. Weld size, at the start and stop and elsewherealong the length of the weld, is an indication of heatinput and potential HAZ hardness. Poor weld starts andstops not only create weakness in the weld but also in theHAZ. All welding procedures approved under the provi-sions of the code are based upon an assumption of ther-mal energy control and arc shielding during welding.The welder is required to produce welds that are soundand of the required dimensions at the start and stop aswell as throughout their length.

When intermittent fillet welds are allowed by design, theweld profile outside the limits of required weld lengthneed not have the crater filled. This provision acceptsminor crater depressions, but not cracks or other fusiondefects at the beginning and ends of intermittent welds,beyond their nominal design lengths.

When terminating a weld, completely stopping forwardtravel and filling the crater with full current may causeoverheating and a rejectable weld profile. Crater fillingrequires special techniques such as ramping down thecurrent or quickly reversing arc travel directions.

C-6.26.1.4 Profile. Acceptable weld profiles aredescribed in 3.6. Should the completed weld not bewithin the range of profiles allowed, the technique mayhave deviated from the approved WPS, the WPS mayhave been improper, the welding equipment or consum-ables may have been defective, or a combination of thesefactors may have occurred. Poor profile makes it moredifficult to remove slag, perform NDT, and place subse-quent weld passes with adequate penetration and fusion.

Good fillet weld profiles are very important for goodfatigue performance. Poor profile configurations mayalso inhibit the proper transfer of stress to each side ofthe welded connection, creating excessive concentrationof stress at the toes of the weld. Such stress concentra-tions may be critical in fillet welds or groove welds thatare loaded normal to their axis, but are of less concernwhen the weld is loaded longitudinal to its axis.

C-6.26.1.5 Undercut. Undercut is defined as agroove melted into the base metal adjacent to the weld


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toe and left unfilled by weld metal. Undercut is evaluatedas a notch that will concentrate stress in proportion to thesharpness and depth of the notch. When undercut isnormal to applied tensile stress for primary members,the depth of the undercut is restricted to only 0.25 mm[0.01 in]. Crossframes and diaphragms attached to con-nection plates or stiffeners of horizontally curved girdersare considered primary members. Fillet welds attachingconnection plates or stiffeners to the web of horizontallycurved girders that carry loads from crossframes ordiaphragms are considered part of primary members.Undercut is not structurally significant to welds loaded incompression or shear if the undercut is within reasonableworkmanship limits, considered to be 1 mm [1/32 in]depth. Due to the difficulty in measurement, no criteria isestablished for notch acuity. When undercut exceedsspecified maximums, repair by light grinding is gener-ally superior to cosmetic weld repairs that may damagethe weld or HAZ.

A difficult location for controlling undercut is at the endof web stiffeners where welds made by SAW are termi-nated. The stiffener sometimes suffers a severe undercutnear the snipe (the cut-out that allows the stiffener toclear the web-to-flange welds) because there is insuffi-cient base metal to support the welding heat withoutmelting. Additionally, if the weld runs into the snipe,overlap, slag entrapment and other fusion defects mayresult and create future maintenance problems. To over-come these problems, and because it is desirable to ter-minate stiffener welds away from the web to flangewelds, some Owner specifications require stiffener weldsto start or stop 5 mm to 10 mm [3/16 in to 3/8 in] fromthe snipe. The problem of undercutting is not as severe atweld starts, so some welding operators stop the SAWequipment near the center of the girder web and restartthe weld from the opposite end to avoid a weld stop nearthe snipe. Because there is little applied stress on thestiffener at the snipe, localized undercut on an intermedi-ate stiffener near the snipe, unless unusually deep, willnot adversely affect performance. Undercut is usually onthe stiffener, due to gravity effects of the weld pool,rather than the web where undercut in tension areas canbe critical. After all appropriate steps have been taken tolimit the amount of undercut, the Engineer may elect toavoid unnecessary weld repairs and allow increasedamounts of localized undercut on stiffeners near snipes.

C-6.26.1.6 Piping Porosity. Historically, the AWSWelding Codes, including D1.1, have not concernedthemselves with porosity in fillet welds unless the poros-ity breaks through the surface of the weld. Subsurfacepiping porosity in fillet welds may be so extensive, withlittle indication of porosity problems at the surface, thatthe welds may crack. This subclause was prepared spe-

cifically for the Bridge Welding Code to deal with theproblem of potentially dangerous amounts of porosity infillet welds that do not appear at the surface.

Porosity is defined as cavity-type discontinuities formedby gas entrapment during solidification. Piping porosityoccurs when gases escape to the surface as the weldmetal solidifies, leaving behind a path that appears as ahollow tube. When these gas vent holes are observed inweld surfaces, it is an indication that there is too muchgas being produced, or that the weld has solidified toofast to let the gas escape, or both. Frequent small pipingporosity (pinholes) in fillet weld surfaces, or large pipingporosity at any time, are an indication that something iswrong with the welding procedures, surface conditions,or welding consumables.

Because porosity is a rounded discontinuity, it is muchless likely to initiate fatigue cracking than planar discon-tinuities. Fatigue tests have shown that significant indi-vidual porosity and piping porosity may occasionally actas initiation sites for fatigue cracking. Piping porositythat extends to the surface is much more damaging tofatigue life than individual small, subsurface sphericalporosity. However, examination of bridges in servicehave not revealed that the porosity allowed by the code isa significant cause of in-service fatigue cracking.

Web-to-flange fillet welds are to be made on base metalthat has all mill scale removed. Stiffener and other filletwelds may be made through tight mill scale, possiblyproducing gas. However, filler metals and welding pro-cedures are available to produce sound welds under bothwelding conditions.

Piping porosity can also be an indication of a problemwith the WPS, or that the welding procedure is not beingproperly controlled. One possible correction, after theelimination of all possible sources of joint contaminationsuch as moisture and oil, may be to raise the preheat,keeping the weld pool molten longer to allow the gasesto escape. The combination of welding heat input andpreheat is not to exceed the manufacturer’s recommenda-tions or the limits on controlled variables containedwithin the PQR, whichever governs the WPS.

When more than a few scattered porosity vents arepresent in fillet weld surfaces, it is an indication thatthere may be extensive subsurface porosity. Provisionsare made by this subclause for a subsurface investigationof fillet welds, at mid-throat depth, after the surface weldmetal has been removed. Weld soundness is determinedby excavation and visual inspection because fillet weldscannot be effectively inspected by RT or UT.

(1) When large or frequent gas vents (piping poros-ity) in fillet weld surfaces are present, or other conditions


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indicate that subsurface porosity may be extensive, asubsurface inspection is necessary.

(2) After the fillet weld surface is removed to mid-throat depth, porosity may be revealed that is much moreextensive than at the surface. Compared to surface poros-ity, a larger volume of porosity can be present in theweld at this mid-throat level and still be consideredacceptable. Surface porosity measurements were used asan indication of potential subsurface porosity problems.When viewed at the mid-throat level, every pore isincluded in the sum of the diameters of piping porositymeasured.

When porosity exceeds the limits of these specifications,the weld is removed and replaced. It is important to iden-tify problems with porosity early and make necessarycorrections to the WPS, or the materials preparation, asnecessary to keep gas-related discontinuities to a mini-mum. Other solutions include the use of lower depositionrates and the use of active fluxes. As with all repairs,extensive weld removal and rewelding is expensive, andif not done properly, may damage the base metal.

C-6.26.1.7 Underrun. Most fillet welds are intendedto be equal leg isosceles triangles of weld metal. Theplans may require fillet welds with unequal legs for spe-cial applications. Single pass fillet weld shapes and sizesare controlled by gravity, the location and orientation ofthe welding electrode(s), and the total welding heat inputper unit length. Size can be increased or decreased byadjusting the travel speed, wire feed speed and/or cur-rent. In multipass fillet welding, the size and shape of thefinal weld is determined by the sequence, location, andsize of individual weld passes. Weld bead sequence pro-vides a support for each subsequent weld pass. Filletweld size and contour control requires skill and carefulmonitoring of the welding procedure.

The horizontal shear between most components of bridgemembers that are joined by fillet welds is generally asmall percentage of the ultimate shear capacity of thefillet welds.

Fillet weld size is often governed by minimum weld sizerequirements. Procedures selected for fillet welds ensurethat each pass has sufficient heat input to fully fuse toadjacent base or weld metal and that the HAZ will not beunacceptably hardened. Minimum heat input require-ments generally control minimum fillet weld size. Oncea fillet weld is completed, a size deficiency (implyingunacceptable HAZ hardening) may be correctable bypreheating and depositing another weld pass with suffi-cient heat input to modify the original weld pass andHAZ; but this may lead to significant residual stressesand distortion. In case of deficient fusion or to modify

the HAZ without oversizing the weld, the deficient weldshould be removed and rewelded.

Fillet weld size should be carefully monitored duringthe original welding. Small “cosmetic” passes are notallowed, so if underrun is sufficient to require repairwelding, the minimum heat input for each pass satisfiesTable 2.1 or 2.2, or subclause 5.12 or 5.13, as applicable.This subclause provides a rational method for dealing withslight localized underruns in size that have virtually noeffect upon strength, performance, or the quality of theHAZ. Underrunning in size is not allowed at the ends ofgirders where the horizontal shear stress is the highest.

C-6.26.1.8 Piping Porosity in CJP Tension Joints.CJP groove welds carrying applied tension, which alsoinclude welds subject to reversal of stress, are notallowed to have any visible porosity in the surface of anyweld pass. Piping porosity is an indicator that more sig-nificant piping porosity may be present below the sur-face. Corrections should be made when defects are firstnoted during welding, not after the weld is completedand when repair will be much more difficult. So thatwelders and inspectors will know where these provisionsapply, tension welds should be identified on the plansand shop drawings.

For groove welds other than CJP groove welds in appliedtension, the limits for piping porosity are the same as thatfor fillet welds. Rather than remove the weld to mid-depth, as in fillet welds, groove welds may be nonde-structively tested using RT or UT to determine the exist-ence and volume of both rounded and piping porosity.The limits for such porosity are provided in 6.26.2 and6.26.3.

C-6.26.1.9 Time of Inspection. Inspection of com-pleted welds may begin immediately after the welds havecooled, except for the high strength quenched and tem-pered Grade 690 [100] and 690W [100W] steels. Otheraspects of visual inspection are performed before and dur-ing welding. The Grade 690 and 690W [100 and 100W]steels listed in this subclause are required to be subjectedto a final acceptance inspection not less than 48 hours afterthe weld is completed. As the strength levels of steelsincrease, so does the concern that hydrogen may causecracking. Most hydrogen-assisted cracks in quenched andtempered steels occur within the first 48 hours, eventhough hydrogen-assisted cracks have been known tooccur much later under some unusual conditions. Thewaiting period specified in this subclause is considered tobe reasonable. It will ensure that hydrogen-assisted crackshave had a chance to form, but does not interfere unneces-sarily with the continuation of construction.

C-6.26.2 Radiographic and Magnetic Particle Inspec-tion. Evaluating the quality of welds as specified in this


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subclause is done by examining either images on radio-graphic film or indications of discontinuities at or nearweld surfaces as highlighted by magnetic particles. It isthe intent of the code that RT and MT indications of dis-continuities be treated essentially the same, even thoughthey are performed and interpreted differently.

Indications of discontinuities in radiographs are theresult of changes in the attenuation (scatter and absorp-tion) of penetrating radiation. Discontinuities such asporosity, lack of fusion, slag, and cracks in the weldmetal are less dense than solid steel, allowing moreradiographic energy to penetrate the joint and expose thefilm. Indications of discontinuities are seen as gray orblack areas in the radiograph. To reliably detect unac-ceptable discontinuities, the radiographs provide therequired radiographic sensitivity and film quality, andthe technicians that review the radiographs need to beskilled and thorough in their examination. Techniciansalso use proper illuminating equipment and review radio-graphs under conditions of subdued light to see all signif-icant images in the radiographs.

Radiographs are essentially plan views of the contents ofgroove welds, as seen from the top or bottom, so lengthsand widths of discontinuities are easily measured. Whendiscontinuities are elongated vertically, parallel to theinspecting radiation as in the case of piping porosity, allone sees in the radiograph is the top or plan view of thediscontinuity. Tight cracks and other planar defects mayappear gray in a radiograph, or may not be detected at all,if the inspecting radiation is not aligned with the plane ofthe discontinuity. The radiographic image gives no indi-cation of actual flaw size under these conditions.

Discontinuities may be distorted, or enlarged, in radio-graphs when part, or all, of the radiographic film isexposed by radiation that has penetrated the weld at anangle that deviates significantly from 90°. The greaterthe angularity or misalignment of the inspecting radia-tion, the greater the distortion of images of discontinui-ties in the radiograph. When this occurs, the requiredimage quality indicators (penetrameters) will also bedistorted. If, for example, penetrameters that measure12 mm by 38 mm [1/2 in by 1-1/2 in] are longer or widerin the radiograph, it’s reasonable to expect that disconti-nuities in areas of the radiograph adjacent to the pene-trameter will be similarly distorted (see Clause 6, Part B).

Indications of discontinuities in radiographs are expectedto properly represent the plan view dimensions, lengthand width, of the actual discontinuities. It is not possibleto determine the through-thickness height or location of aweld discontinuity by reviewing radiographs. There is noaccurate way to determine the depth of a discontinuitybelow the surface, or to determine if more than one dis-

continuity is located above another in the cross section ofthe weld. Although specific discontinuities such ascracks, lack of fusion, slag, and porosity have recogniz-able forms in radiographs, through-thickness flawdimensions cannot be determined without further testingby UT, or by measuring after successive excavations.

When radiographic inspection is performed as requiredby the code and the radiographs meet all code require-ments, indications of weld discontinuities in the radio-graphs should accurately represent the plan view size ofthe discontinuities.

Magnetic particle indications of discontinuities may belarge or small, sharp or fuzzy, depending upon thestrength of the magnetic field that has been interrupted,the orientation of the discontinuity in relation to the mag-netic lines of flux, the size of the discontinuity and thecloseness of the discontinuity to the surface. Subsurfacediscontinuities, especially when using AC power maynot be discovered by MT. Even with rectified DC, MTmay only penetrate 2 mm to 5 mm [1/16 in to 3/16 in].Discontinuity size cannot be judged solely upon the sizeof the MT indication. To determine the full extent of adiscontinuity that produces an MT indication, it may benecessary to excavate by progressive grinding down tothe discontinuity.

MT and RT indications of weld discontinuities are notthe same, even though the acceptance criteria is the sameunder the provisions of this subclause. Figures 6.8 and6.9 refer to both groove weld size and fillet weld size andmay be used, as appropriate, to determine acceptance cri-teria when less than perfect fusion exists between theweld and base metal or between weld beads. Radio-graphic testing of fillet and PJP groove welds is onlyappropriate in rare instances as an investigative tool, andis not a normal duty for QC or QA (see 6.7.2).

C-6.26.2.1 Welds Carrying Tensile Stress. Theradiographic weld quality standards of this code are iden-tical to the provisions of AWS D1.1. These standards hadtheir beginning in the ASME Boiler and Pressure Code,Paragraph UW-51, and were modified and adopted forbridges in the late 1950s. In the Boiler Code, there wasno concern for ends of welds, or intersections of web-to-flange welds in bridge members, where there is a con-centration of stress. The Boiler Code, at that time, lim-ited the maximum discontinuity size to one-third theminimum thickness joined, placed limits on the proxim-ity of discontinuities to each other, and required that theaccumulated length of discontinuities not exceed thethickness joined, or size of the weld, in a length of sixtimes the thickness. The criteria was also establishedbased upon the best quality of welds that were being pro-duced at the time and the capabilities of the inspection


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process, rather than the quality needed to sustain theloading and service condition.

For welds carrying tension, Figure 6.8 establishes themaximum discontinuity size and the required separationbetween discontinuities, based upon the size of the dis-continuity and the proximity of the discontinuity to otherdiscontinuities or areas of high residual or applied stress.All discontinuities are viewed as potential sites forfatigue crack initiation, on the assumption that even arounded discontinuity will sharpen and grow if subjectedto enough cycles with a sufficient stress range. Cracks ofany size are never allowed to remain. Other discontinui-ties less than 1.6 mm [1/16 in] in size, as viewed in theradiograph, are considered innocuous, provided theircumulative dimensions are within limits (see 6.26.2.3).Other discontinuities are acceptable or rejectable basedupon type, size, and location. Discontinuities equal to orgreater than 1.6 mm [1/16 in] in size are not allowedwithin dimension “C” of a flange edge, or the toe or rootof a web-to-flange weld, because of the high residualstress in those areas. Restrictions on discontinuity size inareas adjacent to flange edges, or subject to high stressnear intersecting welds, is considered in terms of fractureresistance since they are more susceptible to brittle frac-ture than areas that are completely surrounded by basemetal.

C-6.26.2.2 Welds Carrying Compressive Stress.Many material and workmanship requirements of thecode are based upon a concern for discontinuities initiat-ing fatigue cracking, and eventual failure by brittle frac-ture. When the plans identify welds that will be subjectto only compressive stresses, some weld quality stan-dards can be relaxed without fear that there will be anyadverse effect on performance or safety. This subclauseallows radiographed welds subjected only to compres-sion to contain discontinuities that are roughly twice thesize of those allowed in tension groove welds. Disconti-nuities are also allowed to exist closer to plate edges forcompression welds, compared to the “C” dimension cri-teria for tension welds.

C-6.26.2.3 Discontinuities Less Than 1.6 mm[1/16 in]. Individual discontinuities less than 1.6 mm[1/16 in] in size as seen in the radiograph are consideredinnocuous, and are usually porosity or small slag inclu-sions. However, when the sum of the maximum disconti-nuity dimensions in any lineal 25 mm [1 in] exceeds10 mm [3/8 in], the weld is considered defective andrepairs are necessary.

C-6.26.2.4 Limitations. The weld quality figures indi-cate that maximum flaw size and minimum clearancesare proportional to weld size, up to a 38 mm [1-1/2 in]weld. Beyond a 38 mm [1-1/2 in] weld size, the criteria

remains constant for flaw size and clearance. The figuresare not to be extrapolated.

C-6.26.2.5 Annex A Illustration. Annex A illustratesthe requirements of this subclause. Annex A illustratesthat all welds are not required to be perfect, and alsoassists in the interpretation of these provisions.

C-6.26.3.1 Acceptance Criteria. The ultrasonic test-ing acceptance criteria listed in the code are in additionto the visual inspection standards and any MT, PT, or RTrequired by code or the Contract Documents. Whenultrasonic testing of welds is required, welds areaccepted or rejected based upon the amplitude ofreflected sound, measured in decibels. The number ofdecibels of ultrasound reflected from a discontinuity maygive little or no indication of the type of discontinuity, itssize, or the possible effect of the discontinuity on bridgeperformance. The ultrasonic testing acceptance criteriaspecified in the code are separate from and cannot becompared to any other weld acceptance criteria.

(1) Welds subject to tensile stress under any condi-tion of loading are ultrasonically acceptable if they con-form to the acceptance requirements of Table 6.3. Thetensile stress referred to is applied stress, not residual orsecondary stress. Table 6.3 was designed based upon theassumption that discontinuities reflect sound in propor-tion to the severity of their adverse impact on perfor-mance. When the present ultrasonic testing standard wasbeing developed in the late 1960s, it was assumed thatradiographic inspection produced a 2% sensitivity. Theultrasonic testing acceptance-rejection standards ofTable 6.3 were initially determined mathematically, in aneffort to cause rejection of a discontinuity whenever thethrough-thickness dimension and length were greaterthan that allowed by the RT provisions of the code. Littlethought was given to misalignment of the inspectingsound beams, other than to treat 60° and 45° search unitsdifferently than 70° transducers. It was assumed that aspecific reflector size would produce a specific indi-cation rating, and that acceptance or rejection couldbe based upon indication rating, length and location (seeC-6.7). An indication rating, as described in Annex F, issimply the amplitude of reflected sound compared to acalibrated amount of initially transmitted sound, aftercorrections have been made for sound losses due toattenuation (absorption by the steel). A direct mathe-matical conversion of discontinuity size to decibels ofreflected sound, using these assumptions, producedexcessively restrictive acceptance standards for welds inthin steel. Changes were made to Table 6.3 in the late1970s to make acceptance of welds in thin material lessrestrictive, and to reduce the number and extent ofunnecessary repairs previously mandated.


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There is no reliable relationship between weld disconti-nuity type, orientation, size or severity, and the indicationrating. However, no other workable method of ultrasoni-cally testing welds in bridge members has been devel-oped and none is referenced by the code. Research hasshown that welds that are ultrasonically tested as speci-fied in the code and accepted or rejected based uponthe standards of Table 6.3 are very unlikely to containdefects that will impair bridge safety or fatigue life.However, more than amplitude alone should be consid-ered in the acceptance or rejection of welds based uponUT.

(2) In general, the acceptance standards for compres-sion welds described in Table 6.4 are four to six decibelsless critical than the acceptance standards for tensionwelds listed in Table 6.3. A decrease of six decibels inthe indication rating is roughly equivalent to doublingthe theoretical size of an acceptable discontinuity. Table6.4 is the same as that used in AWS D1.1 as the accep-tance standard for statically loaded, nontubular welds inbuildings. The compression weld standards of the codeare conservative.

C-6.26.3.2 Indications. It is recognized that disconti-nuities do not generally reflect ultrasound in proportionto the effect of the discontinuity on the integrity of theweld. Three additional testing and evaluation instruc-tions are provided in the following numbered provisionsso that major defects are not missed or mistakenlyaccepted based upon ultrasonic tests. All nondestructivemethods are subject to some significant inherent limita-tions. The sizing and characterization of discontinuitiesin weldments often cannot be done accurately by ampli-tude alone, as required by the current code provisions.Discontinuities that may lead to failure are reliablydetected by the prescribed scanning procedures, but maynot accurately be identified as rejectable. Under someconditions, cracks produce amplitude responses whichdo not give an accurate indication of their size or effectupon the integrity of the welded joint. If indicationsremain on the display as the probe is moved significantlyin the required scanning direction normal to the indica-tion and adjusted for the scanning amplitude, discontinu-ities should be considered unacceptable until a moredetailed evaluation can be accomplished. These pre-cautions have justified the preparation of this subclauseas follows:

(1) Ultrasonic testing has the ability to detect discon-tinuities and to accurately determine their location withinthe weld or adjacent base metal. UT can also determinethe length of discontinuities with sufficient accuracy toestimate the effect of the discontinuity on performance.However, UT has considerable difficulty determining thediscontinuity or flaw height, even though efforts have

been made to increase the accuracy of this measurement,because the height of elongated discontinuities is criticalto performance in a fracture mechanics analysis. As thesearch unit (transducer) is moved forward and back in ascanning movement normal to the weld axis, shown asscanning movement B in Figure 6.7, a consistent indica-tion of a reflector on the display indicates the presence ofa discontinuity with considerable through-thicknessheight. This provision is designed to warn that when anindication remains on the display during scanning asdescribed, there is a likelihood that the discontinuity hasconsiderable height in the weld cross section and may bea crack or a crack-like defect such as a lamination or lackof fusion.

(2) 70°, 60°, and 45° transducers are used in anglebeam ultrasonic testing. That means that the sound beamis 20°, 30°, or 45° misaligned from being perpendicularto the most critical flaw orientation, depending on thesearch unit used. 60° and 45° transducers can producesound beams normal to weld preparations that have com-plementary angles. This produces increased sensitivitywhen there is concern for the quality of fusion at initialjoint groove faces. However, the most critical flaw orien-tation is normal to the applied tensile stress, which isnormal to the base metal surfaces. Fusion discontinuitiesat prepared joint surfaces, normal to the inspecting soundbeam, generally produce very high amplitude responsesin proportion to their size. This converts to very low indi-cation ratings as calculated in Annex F, Figure F.5, andgenerally results in the weld being rejected under theprovisions of Table 6.3. The discontinuity may or maynot seriously affect performance, depending upon sizeand type of discontinuity. When a defect is normal to thesurface of the joint and completely surrounded by soundmetal, there is a likelihood that it will be difficult todetect. Almost all of the sound may be reflected awaywith essentially none reflected back to the transducer.Fortunately, most cracks are somewhat irregular and fac-ets of the surface provide enough reflected sound to indi-cate their presence. If there are indications of flawheight, regardless of amplitude, a crack may be present,and soundness should be verified by other wedge anglesand locations or alternate inspection methods or tests.

(3) Planar indications become increasingly difficultto detect as angular misalignment with the UT beamexceeds 7°. Slight irregularities in the surface and at thetop and bottom of even planar discontinuities help tomake them more visible. Scanning is done at very highamplitudes so that poor reflectors, which may be criticalflaws, may be detected. Scanning levels are described inTables 6.3 and 6.4. When reflectors remain on the dis-play during scanning using Movement B, the weldshould not be accepted until other tests have verified that


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it is sound. The image of a reflector with considerablethrough-thickness height will appear to move across thedisplay as the sound path is changed by forward andbackward movements of the transducer. This is some-times referred to as a “walking image” and is an indica-tion of significant flaw height. Thin elongateddiscontinuities with little through-thickness height do notproduce this type of flaw indication, so forward andbackward movements of their transducer cause theirimage to disappear. There is a sharp peak in signalamplitude when the sound beam is focused on the mostreflective portion of the discontinuity.

C-6.26.3.3 Scanning. Except in unusual conditions,web-to-flange welds are designed to carry only horizon-tal shear stresses. Fillet welds and CJP groove weldshave the same design fatigue life when carrying onlyshear stress. When horizontal shear is the only applieddesign stress in CJP web-to-flange groove welds, it isless essential that weld soundness meet all requirementsspecified for CJP tension groove welds in bridges. Minordiscontinuities, parallel to the applied stress, will havelittle adverse effect. Acceptance of CJP web-to-flangewelds is allowed based upon the compression weld stan-dards of the code and a material thickness that is 25 mm[1 in] greater than the actual web thickness. This pro-vides adequate weld soundness, and avoids unnecessaryrepairs that may create more serious weld defects orfatigue problems.

(1) While discontinuities parallel to the applied stressare treated more leniently, discontinuities normal toapplied stress are not. Scanning Pattern E is used to dis-cover discontinuities normal to applied stress. Indica-tions, when discovered, should be evaluated to thetension weld standards of the code based upon actualweb thickness. This is a conservative requirement and isjustified by the high residual stresses at this location, andalso because a transverse crack in a longitudinal weldcarrying shear is serious. Cracks, if present, should alsobe verified by visual inspection and MT. The welddescribed is tested to a more lenient standard because theflange is thicker, even though the web and flange havethe same residual and applied stress at any commonpoint. Care should be taken not to require unnecessaryrepairs based upon misinterpretation of these provisions.

(2) When portions of web-to-flange welds will actu-ally carry applied tensile stress normal to the weld axis,they should be identified on the plans and on the shopdrawings so that all parties will verify the welds meet allrequirements for tension groove welds (see C-6.7).

C-6.26.4 Liquid Penetrant Inspection. PT is an aid tovisual inspection. The size of PT indications is notalways a reliable guide to the size or nature of the discon-

tinuities they represent. When discontinuities are discov-ered by PT, remove all traces of dye and developer andevaluate the discontinuity visually. Localized, progres-sive excavations by grinding may be necessary to accu-rately size and characterize discontinuities. High steeltemperatures and crevices on the surface may make PTless reliable.

C-6.26.5.1 Time of Testing. MT, UT, and PT areallowed to be performed as soon as the welds havecooled, except for Grade 690 [100] and 690W [100W]steels. PT may not provide accurate indications if per-formed while preheat is maintained.

C-6.26.5.2 Grade 690/690W [100/100W] Steels.When Grade 690 [100] and 690W [100W] high strengthquenched and tempered steels are welded, final accep-tance testing should not be done until at least 48 hoursafter completion of the weld, including repairs. Sub-clause 6.26.1.9 places the same restrictions on visualinspection. These requirements are based upon a concernthat hydrogen-assisted cracks may form after inspectingand testing, if performed immediately after cooling. Pre-liminary testing may begin sooner. If unacceptable dis-continuities are found prior to the 48-hour elapsed time,it is not necessary to delay repairs, however, repair meth-ods may also cause crack initiation.

C-Tables 6.3 and 6.4. The Ultrasonic Acceptance-Rejection Criteria listed for welds subject to tensile andcompressive stresses are based upon the same testingmethods and assumptions. Tension weld standards aregenerally 6 dB more sensitive, representing a theoreticalflaw size of approximately half that allowed for com-pression welds. Flaw Severity Class is based upon dis-continuity length: Class A discontinuities are rejectableregardless of length; Class B discontinuities are reject-able when the length exceeds 20 mm [3/4 in]; and ClassC discontinuities are rejectable when the length exceeds50 mm [2 in] in the middle 1/2 thickness, or 20 mm[3/4 in] in the top or bottom 1/4 thickness. The Class Ccriteria reflects the fracture mechanics principle thatsurface flaws are roughly twice as sensitive to brittlefracture as buried flaws of equivalent size. Class D dis-continuities are acceptable regardless of length or loca-tion. Class B and C flaws are required to be separated asstated in Notes 1 and 2. These requirements are similar tothe RT provisions of Figures 6.8 and 6.9, except that forUT, restrictions are not placed on discontinuity size inareas adjacent to the toe, or root, of any intersectingflange to web weld as stated in 6.26.2.1. The weld qual-ity provisions for RT and UT were intended to be identi-cal, but minor differences have resulted from differencesin the testing methods.


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Note 3 requires that CJP tension welds identified on thedrawings have discontinuities in the root face area of thewelds evaluated to a 4 dB greater sensitivity than the restof the weld. This reflects concern that unfused, smoothroot faces are poor reflectors, similar to smooth cracks.Because CJP groove welds are required to be back-gouged to sound metal and verified visually before weld-ing the second side, discontinuities of this type shouldnot be present.

Note 4 warns of the tests necessary to ensure that dis-continuities with significant through-thickness size are notmissed, or incorrectly evaluated, based upon amplitudealone.

The acceptance-rejection criteria of Tables 6.3 and 6.4are grouped by thickness because the indication rating isrepresentative of through-thickness size. The greater thethickness of the CJP groove weld, the greater the weldarea and therefore the greater the size of the allowablediscontinuity. The Tables were initially designed toduplicate Figures 6.8 and 6.9 and to reject weld disconti-nuities that exceed 2% of the thickness for the lengthsstated, but until the flaw height is 7% of the thickness orgreater, detection and rejection by UT may be unreliable.

The different acceptance-rejection indication ratings for70°, 60°, and 45° transducers are based upon an assumedrelationship between the sound path and the plane of thediscontinuity. The search unit is made up of a transducerand an angle beam sound wedge that is used to producethe required search angle. The different acceptance lev-els, based upon an assumed sound misalignment, are notprecise. When the discontinuity orientation is not clear,testing should be done using multiple search unit angles

and acceptance-rejection decisions should be made usingthe values listed for the largest angle search unit. Adding3 dB and 5 dB to the sensitivity of the 60° and 45° searchunits because of an assumed misalignment is not appro-priate. The sound beam from these search units may benormal to the plane of the discontinuity, or at least aswell aligned with the reflecting surfaces as sound from a70° search unit.

The ultrasonic testing provisions of this code were origi-nally issued in AWS D1.1-69. It is understood that thereare errors in the theory upon which the testing proce-dures were developed. Still the UT method providesreproducible results and has been effective in discover-ing and rejecting most harmful defects. Efforts todevelop better procedures are ongoing.

The testing provisions as provided in the code apply onlyto CJP groove welds subjected to applied stress normalto the weld throat, except as provided in 6.26.3.3. Searchunit size and shape conform to 6.15.7.2. Smaller and dif-ferently shaped transducers produce amplitude responsesthat cannot be used to determine weld acceptance orrejections under the provisions of this code.

Rejectable weld and base metal indications can be veri-fied by careful progressive excavation. If, upon investi-gation using proper lighting and magnification asnecessary, a visible discontinuity cannot be found, ultra-sonic testing may not have been done properly.

For ESW and EGW, high welding heat inputs create verylarge grain structure, making interpretation of UT muchmore difficult. Grain boundaries may reflect sufficientlyto appear as defects, although excavation may not dis-close any discontinuity.



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C-7.1 ScopeStud welding is unique among the approved welding pro-cesses in this code. Not only are the arc length and theweld time automatically controlled by the welding equip-ment, but a significant production proof test is required.With correctly set equipment, good workmanship andproper technique, the stud welding process can producea large number of essentially identical sound welds.Because of the production proof testing, qualificationbased upon Clause 4 and written WPSs is not required.This is a basic difference from the other approved weld-ing processes in this code, therefore stud welding hasbeen placed separately in Clause 7.

This subclause includes testing to establish mechanicalproperties and the qualification of stud bases by the studmanufacturer, testing to establish or verify the weldingsetup (essential variables), and testing to qualify specificapplications and the welding operator, as well as inspec-tion requirements.

C-7.2 General RequirementsGeneral requirements prescribe the physical dimensionsof studs and describe the arc shield and stabilizing flux tobe used. These stud base assemblies are qualified by themanufacturer as described in Annex E of this code.

C-7.2.1 Dimensions are provided for the manufacture ofthe studs, with rigid tolerances to assure compatibilityand proper operation with the stud welding equipment.The finished height of the as-welded stud is approximately3 mm to 5 mm [1/8 in to 3/16 in] less than the manufac-tured stud length, with stud length reduction less forsmaller diameter studs than for large diameter studs.

C-7.2.2 The purpose of the arc shield (ferrule) is: (1) toconcentrate the heat of the arc in the weld area, (2) torestrict the flow of air into the weld area, controlling oxi-dation, (3) to confine the molten metal to the weld area,

(4) to prevent the charring of adjacent materials, and (5)to shield the operator from the arc.

C-7.2.3 The purpose of the flux at the tip of the stud baseis to stabilize the arc and to hinder or prevent the forma-tion of oxides and other undesirable inclusions in themolten weld pool, created primarily from impurities onthe base metal surface but also present in the atmosphereand within the steel itself.

C-7.2.4 The purpose of the stud base qualification testingdescribed in Annex E is to verify that the manufacturer’sdesign of the stud base, with the use of the stabilizingflux tip and the particular geometry of the stud end, incombination with the appropriate arc shield, will providesuitable strength and quality when used in properly setstud welding equipment. Only the common applicationof the flat (plate surface horizontal) welding positionrequires testing by the manufacturer. The manufacturermay also perform stud base qualification tests throughdecking, but these welds are also subject to qualificationtesting in conformance with 7.6.

C-7.2.5 A quality stud finish is needed for proper func-tioning with the stud welding equipment. Cracks andother sharp discontinuities in the shank of the stud maylead to cracks in the stud weld itself.

Small cracks in the head of the stud, also called bursts,do not inhibit the proper functioning of the stud. Thebursts are typically caused by the expansion of small,undetectable seams in the surface of the rod or wire fromwhich the stud is made, expanded by the heading func-tion during manufacture. In some cases, bursts are causedby the radial stresses from the expansion of material dur-ing heading. Large bursts may be indicative of deeperseams within the shank of the material that may have goneundetected during visual inspection.

C-7.2.6 To allow verification that the studs to be usedand the welding essential variables are within the bound-aries of the testing performed and the manufacturer’srecommendations, the Engineer may require test data

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from the Manufacturer’s Stud Base Qualification testing(see Annex F10 for the manufacturer’s standard testdata).

C-7.2.7 AASHTO M270M [M270] (ASTM A 709M[A 709]) Grade 690/690W [100/100W] steels are heattreated. The heat from stud welding may reduce basemetal static or dynamic mechanical properties. For exam-ple, thin quench and tempered steel may have reducedtensile properties, and thicker quenched and temperedsteels are more likely to have higher hardness and reducednotch toughness in the stud weld HAZ. Underbead crack-ing is possible. For these steels, the use of preheat in con-junction with the stud welding may be necessary to reducethe high HAZ hardness and reduce the risk of cracking.The Engineer should evaluate applications where studswill be welded in members subject to cyclic tensile stressor stress reversal. The Qualification Test of 7.6 verifiesonly that the stud itself is acceptable on the steel used, notthat the steel will have satisfactory properties.

C-7.3 Mechanical RequirementsType A studs have a lower strength and are for generalpurpose use, so they are not permitted to transfer designshear in composite construction. The higher strengthstuds, Type B, are used as an essential component ofcomposite beam construction.

C-7.3.1 The material described provides suitablemechanical properties for the manufacture, welding andperformance of studs. Other ASTM A 108 bar stockgrades may be more difficult to manufacture, be unsuit-able for welding, or fail to have the strength and ductilityrequired for proper stud behavior.

C-7.3.1.1 Only Type B studs have a minimum specifiedyield strength, necessary for proper in-service performance.

C-7.3.1.2 Testing for steel strength may be performedafter the cold finishing operations. The cold working ofthe stud surface during drawing and finishing increasesthe strength of the material, but also reduces its ductility.The heat generated from the stud manufacturing opera-tions is not enough to affect either the strength or ductil-ity of the finished product below that of the cold finishedsteel.

C-7.3.3.1 The Engineer may require a statement ofcertification attesting that the product supplied meets allapplicable mechanical property requirements, in additionto the stud base qualification data of 7.2.

C-7.3.3.2 The Engineer may require copies of themanufacturer’s recent quality control test data to confirm

that the product supplied meets all required mechanicalrequirements. It is assumed that the product supplied wasmanufactured and tested within the six-month periodprior to delivery. This documentation is used in lieu oflot traceability and testing requirements.

C-7.3.4 If quality control reports are not provided,mechanical testing is performed by the Contractor ormanufacturer on the studs provided. The Engineershould determine the number of tests performed basedupon the quantity of studs required and the homogeneityof the studs supplied.

C-7.3.5 Testing of individual studs or a selection of studsbased upon diameter and length may be required by theEngineer. Such testing is in addition to the testing previ-ously provided by the manufacturer or Contractor underthe provisions of 7.2 and 7.3, and is at the Owner’sexpense.

C-7.4 Workmanship. The fillet weld profiles shown inFigure 3.3 do not apply to the flash of automaticallytimed stud welds. The expelled metal around the base ofthe stud is designated as flash in conformance withAnnex D of this code. It is not a fillet weld such as thoseformed by conventional arc welding. The expelled metal,which is excess to the weld required for strength, is notdetrimental but, on the contrary, is essential to provide agood weld. The containment of this excess molten metalaround a welded stud by the ferrule (arc shield) assists insecuring sound fusion of the entire cross section of thestud base. The stud weld flash may have nonfusion in itsvertical leg and overlap on its horizontal leg, and it maycontain occasional small shrink fissures or other disconti-nuities that usually form at the top of the weld flash withessentially radial or longitudinal orientation, or both, tothe axis of the stud. Such nonfusion, on the vertical leg ofthe flash, and small shrink fissures are acceptable.

C-7.4.1 Studs with surfaces contaminated with the mate-rials described may have inadequate electrical contactwith either the welding equipment or the base metal, orboth, resulting in welds with unacceptable porosity, lackof fusion, inclusions and other discontinuities in the studweld.

C-7.4.2 The materials described may cause porosity,lack of fusion, inclusions and other discontinuities in thestud weld. A galvanized surface, because zinc has a rela-tively low temperature melting point, may cause a low-strength area within the completed weld.

C-7.4.3 Foreign materials present on the base metal maycause porosity, lack of fusion, inclusions and other formsof weld discontinuities in the stud weld. Moisture andcoatings contribute hydrogen that adversely affects thecharacteristics of the HAZ. Extra caution is urged when


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welding through decking because there may be areas ofmoisture present between the layers of material that isnot readily detected with visual observation.

C-7.4.4 Arc shield moisture may cause steam explo-sions, porosity, and in rare cases, underbead cracking.

C-7.4.5 In order to meet the design requirements forshear transfer, actual stud placement needs to be close tothe locations specified by the contract. When studs areclosely spaced, they behave like one large stud ratherthan as individual studs. Studs placed very close to theedge of a part may be affected by arc blow during weld-ing, resulting in inadequate weld strength and quality.Tear-out of the base metal is also possible if the stud isvery close to the edge and loaded in the direction of theedge.

C-7.4.6 Following stud welding, used arc shields are tobe removed and a visual inspection made by the weldingoperator. This visual inspection should be performed assoon as practical after the stud is welded, in order toavoid a large number of defective studs should the equip-ment have malfunctioned.

C-7.5.1 The general characteristics for a stud weldingpower source are: (1) high open-circuit voltage in therange of 70 V to 100 V, (2) a drooping output voltage-ampere characteristic, (3) a rapid output current rise tothe set value, and (4) high current output for a relativelyshort time. Power sources for SMAW DC and otherpower sources that do not have constant voltage charac-teristics are generally suitable.

The stud gun consists of a body, a mechanism to lift thestud and then plunge it into the molten weld pool, anadjustable support for the arc shield holder or grip, andthe necessary cables to the stud welding controller.

C-7.5.2 Because of the significant power draw when studwelding, the power source and controller need to be setto weld only one stud at a time. Otherwise, inadequatepower may result in significant weld defects.

C-7.5.3 Movement of the stud welding gun during weld-ing may lead to poor fusion, cracking, lack of completewelding throughout the entire base of the stud, and mis-alignment of the finished stud.

C-7.5.4 Stud welding with base metal temperaturesbelow that specified contributes to excessively rapidcooling of the weld HAZ, increasing the risk of crackingand degradation of the mechanical properties within theHAZ. Moisture present in the weld area contributes toexcessive levels of hydrogen and other gases, increasingthe risk of HAZ cracking, and also causes excessiveporosity, weakening the weld.

C-7.5.4.1 Colder temperatures increase the probabil-ity of stud welding problems because of the more rapidcooling of the HAZ, therefore a minimum of 1 in 100studs are tested with a bend test as described in 7.7.1.4.Lower temperatures also reduce the toughness of theweld and HAZ, therefore the angle of testing is reducedfrom 30° to 15°. The method of testing should be bybending the stud with a pipe or other hollow device,rather than striking with a hammer. Studs are to be left inthe bent position.

C-7.5.4.2 Changes in equipment, equipment settingsor power source require retesting of the WPS to verify itssuitability. Because of the high, short cycle powerdemand, the load voltage and cable voltage drop isgreater for stud welding than with the other welding pro-cesses. Cable length includes both cable from powersource to controller and from controller to stud gun.Adjustment to the operation of the gun itself requirestesting to verify that the gun as modified will producesatisfactory welds.

C-7.5.5 Although the use of automatically-timed equip-ment is generally preferred, the code also allows studs tobe fillet welded, at the option of the Contractor, using theSMAW. Welders need to be qualified in conformancewith Clause 5, Part B, for this application. This optionwas included for cases where only a limited number ofstuds are to be welded, with the Contractor’s decisionusually one of economics, or when the repair or replace-ment of a limited number of studs is required.

Studs welded by the use of automatically-timed weldingequipment or fillet welded by the SMAW process areconsidered welded by a prequalified WPS.

C-7.5.5.1 The minimum size required provides aweld strength equal to or greater than a weld made usingautomatically-timed stud gun welding equipment. Theminimum heat input concerns are addressed by the use ofminimum electrode diameter.

C-7.5.5.2 The electrode diameter is specified to helpensure that minimum heat input is provided. The mini-mum preheat requirements of Table 4.4 also apply. Out-of-position welding may require the use of smallerelectrodes, therefore the heat input of these welds shouldbe evaluated.

C-7.5.5.3 Most studs have chamfered bases and a fluxball that protrudes beyond the end of the stud. Weldingwithout removal of these items would leave a significantgap at the root of the fillet weld, contributing to possiblefusion and porosity discontinuities, as well as an under-sized effective vertical leg. The end of the stud tip isground flush to provide a solid fit between stud and basemetal.


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C-7.5.5.4 Although most SMAW electrodes haveadequate tolerance and fluxing for moderate amounts ofmill scale and rust, all rust and mill scale are removed bygrinding for this application. Even tight mill scale is notacceptable (see C-7.4.1, C-7.4.2, and C-7.4.3).

C-7.5.5.5 The electrode diameter specified in 7.5.5.2assumes that the preheat requirements of Table 4.4 arealso satisfied. Inadequate preheat contributes to higherHAZ hardness and increased hydrogen levels, possiblycausing a degradation of HAZ mechanical properties andhydrogen-induced underbead cracking.

C-7.5.5.6 The visual inspection requirements of 6.5are to be met, including several tasks performed beforeand during the welding. The weld quality requirementsof Clause 3 and the visual inspection provisions of 9.21.1are to be satisfied. No other NDT is normally required.

C-7.6.1 Prequalification. Special conditions whereApplication Qualification Requirements apply includestuds using modified arc shields, studs welded in the ver-tical or overhead positions, studs welded through deck-ing, and studs welded to other than AASHTO M270M[M270] (ASTM A 709M [A 709]) steels.

Modified arc shields may be required when studs arewelded to nonflat surfaces. Vertical stud welds are partic-ularly prone to undercut-like discontinuities at the top ofthe stud. Overhead stud welds may have undercut aboutthe perimeter of the stud. Since these and other specialcases are not covered by the manufacturer’s standard studbase qualification tests, the Contractor is responsible forthe performance of these Application Qualification tests,serving a purpose similar to the WPS qualification testingrequired for the other welding processes.

Stud welding through decking is not prequalifiedbecause of the many testing variables that would beinherent for the Manufacturer’s Stud Base QualificationRequirements: the number of plies, the thickness ofdecking, the coating type, and coating thickness. Theheaviest metal decking thickness, whether one or twoplies, along with the thickest coating (galvanized ifused), would provide a worst case, not necessarily appli-cable to every stud on the project, to verify the adequacyof the equipment to be used. Many manufacturers do per-form such testing for standard thicknesses and coatingsof decking, as provided in Annex E5.1.

C-7.6.2 Responsibilities for Tests. Testing for non-prequalified applications is the responsibility of the Con-tractor. However, the testing may be performed byorganizations other than the Contractor. For decking,many manufacturers perform such testing for standardthicknesses and coatings of decking, as provided inAnnex E5.1. Nonstandard applications such as vertical or

overhead welding may also have been previously tested.Engineers may accept evidence of previous specialApplication Qualification tests, where new work wouldfall within previous limits, with added assurance pro-vided by the preproduction tests using the specific studwelding setup as described in 7.7.1.

C-7.6.3.1 Test specimens for Application Qualifica-tion may be performed on any of the AASHTO M270M[M270] (ASTM A 709M [A 709]) steels, regardless ofthe steel being used for construction. However, shouldthe steel receiving the studs be a steel not described in1.2.2, approved by the Engineer, then the testing shouldbe performed on the steel being used or a representativesample.

C-7.6.3.2 All welding variables and equipment settingsneed to be recorded.

C-7.6.4 Number of Specimens. All ten specimens are tobe welded consecutively, using the welding variables asdetailed in 7.6.3.2. All ten specimens need to pass theprescribed tests, and if any of the ten specimens fails,another ten are tested using the original or appropriatelyrevised welding variables and settings.

C-7.6.5 Tests Required. For headed studs, either thebend test or tension test may be performed. For threadedstuds, the torque test may also be used (see Annex E,Figure E.1A for the locations of acceptable fractures inthe shank of the stud and unacceptable fractures in theweld).

C-7.6.6.2 Torque Test. The torque test may be usedfor threaded studs. The torque value listed is based uponthe lubrication provided from residual standard cuttingoils. The tension produced on the stud will be highlydependent upon the effectiveness of the lubrication pro-vided. Stud threads that are unlubricated or rusty willproduce less tension for a given torque value, and willnot test the stud with the tensile force expected. It is notnecessary to relubricate the stud with new cutting oil pro-vided some residual oil is present. Studs that are relubri-cated with a more efficient lubricant will produce muchhigher tensions for a given torque, and may fail the studin tension. However, failure in this case will typicallyoccur in the threads and not in the weld, therefore thestud weld is considered acceptable. These studs mayhave already achieved the tension expected prior to fail-ure. Figure 7.3 does not state the tension expected basedupon the torque value used, but the torque provided, withresidual cutting oil lubrication, should stress the stud toabout 55% of its tensile capacity based upon the grosscross-sectional area of the stud.

C-7.6.6.3 Tension Test. Using the tension test, thestud is tested to failure. The actual tension required to


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fail the specimen need not be measured, as the accep-tance criteria for this test is based solely upon the factthat the weld did not fracture and that the fractureoccurred in either the stud or base metal. It is assumedthat the stud has the minimum mechanical propertiesdescribed in 7.3.1.1.

C-7.6.7 The data required for Application Qualificationtests is similar to that required of the manufacturer inAnnex F, Clause F10, with the addition of the weldingvariables as recorded in 7.6.3.2.

C-7.7 Production ControlTesting is normally required for the first two studs ofeach day’s or shift’s production, or with any modifica-tion in the setup changing any one of the following: studgun, timer, power source, stud diameter, gun lift andplunge, total welding lead length, or changes greater than5% in current (amperage) or time. Users unfamiliar withany of these terms should refer to AWS C5.4, Recom-mended Practices for Stud Welding.

C-7.7.1.1 Because the suitability of the WPS has beendocumented through either prequalification from themanufacturer’s stud base qualification testing of AnnexE, or through the application qualification tests of 7.6,this test is used only to verify the proper setup of theequipment. Preproduction testing may be done on repre-sentative material of thicknesses approximating that ofthe production piece, or may be done on the productionmember itself unless problems arise.

At the very high currents used in stud welding, it is veryimportant to have adequate lead size and good lead con-nections. Stud gun settings may be inadvertentlychanged between shifts or through handling. For thesereasons, this testing is expected at the beginning of everywork shift, or whenever changes to setup occur (see7.7.2).

C-7.7.1.2 Separate plates may be used for preproduc-tion testing at the Contractor’s option. When stud weld-ing problems occur, testing on plates is required by7.7.1.5 to minimize the damage done to production mem-bers until the proper procedures have been established.

C-7.7.1.3 Stud welding flash around the entire base ofthe stud provides indication of complete welding beneaththe stud. Lack of complete flash indicates problems suchas improper lift or plunge, stud hangup in the gun, move-ment of the stud gun, insufficient welding heat, or failureto use the stud gun perpendicular to the surface. Theseproblems are to be corrected before proceeding with pro-duction welding.

C-7.7.1.4 Bending. At temperatures below 10°C[50°F], some stud and base materials lack adequatetoughness to pass the hammer test.

C-7.7.1.5 If either of the two initial preproductiontests fail to pass the visual flash examination or the bendtest, adjustments should be made followed by a secondpreproduction test with two studs. This second test maybe done on either the production member or other repre-sentative material. If either of the second pair of weldsfail the preproduction test, then conduct all subsequentadjustments and preproduction tests on representativematerial, not the production member, to avoid damageand repair from failed tests.

C-7.7.2 Production Welding. Production welding maybegin as soon as preproduction testing is satisfactorilycompleted. Any adjustments to the equipment, changesin welding lead length, or welding essential variablessuch as current or time beyond 5% require the repeatingof the preproduction testing using full visual inspectionfor complete flash and bend testing (see C-7.5.4.2).

C-7.7.3 In cases of missing flash, bend testing of the studin the direction opposite the missing flash may cause thestud weld to fail, necessitating repair following the pro-visions of 7.7.5. The Contractor may opt to repair theweld by using a fillet weld, provided that all the provi-sions for fillet welding in 7.5.5 are followed. The filletweld need not extend completely around the stud base,but is expected to extend at least 10 mm [3/8 in] beyondthe missing flash.

C-7.7.4.1 The successful completion of the prepro-duction testing of 7.7.1 also qualifies the welding operator.The welding operator’s qualification remains effectivefollowing the provisions of 5.21.4.

C-7.7.4.2 Welding operators not performing previouspreproduction testing may be qualified by performing thepreproduction testing described in 7.7.1.3 and 7.7.1.4.

C-7.7.5 Cracks and other discontinuities created bywelding may propagate from applied tensile stress.Removal of any defect in a tensile area is required, andmay be accomplished by grinding the area smooth andflush.

C-7.7.5.1 Poor stud welding tested using bend testingprocedures may fail, pulling out portions of base metaland HAZ. Should this occur in a tension area, the surfaceof the base metal is weld repaired using SMAW low-hydrogen electrodes, and then ground flush. Compressionarea repairs may be repaired in this manner, or faired bygrinding following the provisions of 7.7.5.2.

C-7.7.5.2 In areas subjected to compression only,repair of poorly welded or failed studs is not required,


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provided they are replaced with a satisfactorily weldedstud. No tensile stresses are present in such regions tofacilitate crack growth. However, if the base metal isreduced in thickness beyond the specified limits, fillingof the divot in the surface of the steel follows the proce-dures described in 7.7.5.1.

C-7.7.5.3 It is not allowed to fill a stud removal areasolely using another stud weld. The area is first repairedusing the methods of 7.7.5.1 or 7.7.5.2.

C-7.7.5.4 Any replacement studs are to be inspectedusing a bend test of 15°, except for threaded studs whichemploy a tension test with an applied torque.

C-7.7.5.5 On areas visible in the completed structure,all remnants of broken studs or welds should be removedand the base metal repaired if necessary and then groundflush.

C-7.8 Inspection RequirementsIn addition to visual and bend tests by the welding opera-tor, representative studs are routinely visually inspectedand/or bend tested by the Inspector.

C-7.8.1 Any production stud not exhibiting full flashabout the perimeter of the stud base is normally bendtested to approximately 15°. Any stud repaired usingSMAW is normally tested in the same manner.

C-7.8.2 Any stud requiring bend testing is bent awayfrom the missing flash. Missing flash is an indication ofincomplete fusion or filling at the base of the stud, and theweakest part of the stud weld in resisting bending.

C-7.8.3 Threaded studs not exhibiting 360° of flashabout the base are tested using torque methods asdescribed in Figure 7.3. The stud is to be consideredadequate if the stud reaches the specified torque (see C-7.6.6.2 for discussion of the torque values).

C-7.8.4 At the Inspector’s discretion, studs may beselected for 15° bend testing, even if exhibiting full flashabout the base of the stud.

C-7.8.5 Studs embedded in concrete perform adequatelyin the bent position. For studs not embedded in concrete,the studs may be bent back into position when required.The use of heat is not allowed to assist in straightening.

C-7.8.6 When the stud failure rate is high, the Engineermay require action to bring the acceptance rate to a suit-able level. Such actions may include repeating of stud basetesting, qualification testing, more frequent preproductiontesting, or other adjustments to the welding operations.

C-7.8.7 Should the Engineer or Owner require the Manu-facturer’s Stud Base Qualification Tests in Annex E to beperformed, the Contractor provides the studs for testingfrom project material, but the studs and testing are at theOwner’s expense.


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The ANSI/AASHTO/AWS D1.5-95 Bridge WeldingCode was the first edition to include a clause for thefabrication and welding of fracture critical nonredundantmembers as part of the code. This clause was the jointeffort of AASHTO and AWS and is intended to replacethe Guide Specifications for Fracture Critical Non-Redundant Steel Bridge Members, which was issued byAASHTO in 1978, including subsequent interim revisions.

C-12.1 General Provisions

This commentary on the Fracture Control Plan (FCP) forNonredundant Members is intended to generate a betterunderstanding in the application of the Plan to the designand construction of nonredundant bridges. The FractureControl Plan should not be used indiscriminately bydesigners as a crutch “to be safe” and to circumvent goodengineering practice. Fracture critical classification isnot intended for “important” welds on nonbridge mem-bers or ancillary products, rather it is only intended to befor those members whose failure would be expected toresult in a catastrophic collapse of the bridge. The safetyand reliability of a bridge is governed by material proper-ties, design, fabrication, erection, inspection, mainte-nance and usage.

Historically, the following fabrication-related factorshave contributed to bridge member failures: designdetails resulting in notches or stress concentrations;design details requiring joints difficult to weld andinspect; lack of base metal and weld metal toughness;hydrogen-induced cracks; improper fabrication, weldingand weld repair; and unqualified personnel in inspectionand NDT. Attention to all of these factors is essential.Too much attention to any one item will not overcomethe effects of a deficiency in any other item.

The implementation of the Fracture Control Plan willhelp ensure that steel bridges with critical tension com-

ponents will serve a useful and serviceable life over theperiod intended in the original design. Fracture CriticalMembers (FCM) are defined in more detail in 12.2 andare basically tension members or portions of members ina bridge whose failure could cause a partial or completecollapse of the bridge with the associated risks to publicsafety. The vast majority of bridges do not have fracturecritical members (FCMs), but it is most important torecognize them and implement appropriate fabricationsafeguards when they do exist.

In addition to the requirements contained in Clause 12 ofthe code, all other provisions of the code apply to theconstruction of FCMs. If there is a conflict between thisclause and other provisions of the code, this clause takesprecedence.

In 1995, the ANSI/AASHTO/AWS D1.5-95 BridgeWelding Code was issued, including Clause 12 that spe-cifically addresses additional requirements for FCMs. TheD1.5 code contains provisions to ensure reliable control ofweld quality. Major changes from the 1978 AASHTOplan (and later modifications) include the following:

(1) Alternative to lot testing criteria for filler metals.(12.6.1.1)

(2) Testing of FCAW and SAW welding consum-ables for diffusible hydrogen in conformance with AWSA4.3 by the gas chromatograph method or under mer-cury rather than the glycerine method. (12.6.2.1)

(3) More extensive controls on exposure of weldingconsumables to atmospheric moisture. (12.6.5–12.6.7.6)

(4) Prequalification of SMAW WPSs for use withlow hydrogen electrodes with a minimum specified ten-sile strength less than or equal to 550 MPa [70 ksi].(12.7.1)

(5) Qualification testing of WPSs for FCMs fullyconsistent with D1.5 requirements for WPSs used onnonfracture critical members. (12.7)

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(6) Extension of WPS qualification testing period ofvalidity from one to three years. (12.7.4)

(7) New tack welding requirements. (12.13)

(8) Preheat levels based upon heat input and diffus-ible hydrogen levels, as well as steel grade and thickness.(12.14)

C-12.2.1 Fracture Control Plan (FCP). The FractureControl Plan referenced and detailed in Clause 12 of thisdocument has replaced the “Guide Specifications forFracture Critical Non-Redundant Steel Bridge Members-1978” developed by AASHTO.

C12.2.2 Fracture Critical Member (FCM). Fracturecritical members are defined as the tension members ortension components of a bending member of a bridgewhose failure would be expected to result in the collapseof the bridge. For the purposes of this code, “collapse ofthe bridge” may include the entire superstructure or asignificant portion that would threaten public safety and/orleave the remaining structure unusable, for example, failureof a pin supporting a suspended truss span. A fracturecritical member may be a complete bridge member orit may be a part of a bridge member such as a web ortension flange.

The identification of such components is, of necessity,the responsibility of the bridge designer because virtuallyall bridges are inherently complex and the general cate-gorization of every bridge and every bridge member isimpossible. However, to fall within the fracture criticalcategory, the component will be in tension due to exter-nally applied loads.

Examples of complete fracture critical bridge membersare tension ties in arch bridges and tension chords intruss bridges, provided a failure of the tie or chord couldcause the bridge to collapse. Some complex trusses andarch bridges without ties do not depend upon any singletension member for structural integrity; therefore the ten-sion member would not be considered a fracture criticalmember.

Critical tension components of members may also occurin flexural members. Continuous multi-span girderbridges will have portions of the girder with either thetop or bottom flange in tension. In a simple span girderbridge, the area from the neutral axis to the bottomflange will be in tension. At any given location, oneflange of a flexural member is in tension and, therefore,would be a critical component if a failure could causecollapse of the bridge, for example a structure using asingle welded box girder or two welded I-girders. Theweb of a flexural member in the above applications isalways partially in tension and similarly can be a criticalcomponent.

Tension members or member components whose failurewould not cause collapse of the bridge are not fracturecritical. Compression members and portions of bendingmembers in compression may be important to the struc-tural integrity of the bridge, but do not come under theprovisions of this plan. Compression components do notfail by fatigue crack initiation and extension, but ratherby yielding or buckling.

The plan provides for additional quality of material andincreased care in the fabrication and use of the materialsto lessen the probability of fracture from crack initiationand extension under in-service loading of critical tensioncomponents.

C-12.2.2.1 Attachments. The provisions of this sub-clause describe what minimum size attachment is to beconsidered a fracture critical member, if it is welded to afracture critical member or member component. Thisattachment length is the minimum length needed totransfer stress into the member and has been establishedas the minimum length which may cause cracks to propa-gate from the attachment into the fracture critical mem-ber because of the flow of stresses between the two.Short members will not attract enough stress to make theattachment fracture critical.

C-12.2.2.2 Welds. Longitudinal stiffeners and otheraccessories which are welded to the compression area ofwebs or flanges are not fracture critical. However, weldsattaching transverse stiffeners to the tension area of webswould be fracture critical. Note that it is the weld and notthe stiffener which is classified as Fracture Critical. Incompression, crack formation and extension would belimited.

C-12.3.1 Design Evaluation. A critical part of any com-plete Fracture Control Plan deals with design and detail-ing. These two items are already included in other partsof the code and this Commentary. Fatigue requirementsare extensively covered by AASHTO Specifications and,where necessary, are made more conservative for frac-ture critical members. Fatigue categories for variousbridge details also are extensively covered. The designeris responsible to examine each detail in the bridge forcompliance with the fatigue requirements and to ensurethat the detailing will allow effective joining techniquesand NDT of all welded joints. The Fracture Control Planbegins with the designer since without proper design,details, and specifications, the Plan will fail.

C-12.3.2 Prebid Designation of FCMs. The Engineer isto ensure those members or member components whichare fracture critical are designated on the contract docu-ments, allowing the Contractor to incorporate relatedmaterial, fabrication, erection, and inspection costs intotheir bid.


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C-12.3.3 Shop Drawings. The shop drawings are pre-pared by the Contractor. The Engineer should, in gen-eral, simply specify the type and size of weld, e.g.,complete joint penetration (CJP), partial joint penetration(PJP), or fillet, and leave the details of the particular jointgeometry to the Contractor. The Contractor is in the bestposition to select details of welded joints that best fit thematerial configuration and shop’s capabilities.

C-12.3.3.1 Engineer’s Review. The Engineer isresponsible for the review of the shop drawings only toensure general conformance with the plans and specifica-tions, including identification of the fracture criticalmembers and that material lists and weld procedures arein conformance with this Fracture Control Plan.

The Engineer also judges the suitability of a WPS for aparticular welded assembly or connection. The coderequires that the Engineer review and accept writtenWPSs prior to their use in production. This review may bemade in conjunction with review of the shop drawings.

C-12.3.3.2 Acceptance. Review and acceptance ofthe Contractor’s shop drawings and WPSs confirms theContractor’s understanding of the design drawings andcontract requirements. Such acceptance does not changecontract requirements, transfer responsibility for the exe-cution of the work to the Engineer or endorse errors oromissions on the shop plans that conflict with the con-tract plans and specifications.

C-12.4 Base Metal RequirementsC-12.4.1 Approved Base Metals. The steels describedin this subclause are approved for welding in bridge con-struction by the AASHTO Subcommittee on Bridges andStructures. These steels are considered weldable andmay be purchased with CVN test values that are suitablefor bridge service at temperatures provided for in thethree separate AASHTO Temperature Zones. The steelsdescribed in 1.2.2 may be joined successfully by adher-ing to the provisions of this code. Other steels may needdifferent controls to produce sound, crack-free weldswith the required mechanical properties. Steels notdescribed in 1.2.2 require an appropriate investigation ofweldability and approval of the Engineer before beingused in this code (see C-1.2.2 for additional informationon this subject).

C-12.4.2 Fine-Grain Practice. Steels manufacturedusing killed fine-grain practice generally have bettertoughness. If a fatigue crack should initiate in steel man-ufactured using killed fine-grained practice, a longercrack can be tolerated before brittle fracture occurs.

Fatigue crack initiation is dependent on stress range,number of cycles, geometry, and initial flaw size, notnecessarily the type of steel. However, fatigue crackpropagation is dependent on the type of steel, such asaustenitic, ferritic/pearlitic, martensitic, etc. Therefore,steel manufactured using killed fine-grained practiceincreases the fracture resistance of these types of steel.Because failure of fracture critical members or membercomponents may result in the bridge collapse, theseenhanced quality steels are required.

C-12.4.3 Prohibition of Mill Repairs. The steel produc-ing mill may not have the quality of welder, WPSs andQA/QC personnel that would be necessary to performfracture critical welding in conformance with the code.In addition, the Engineer and Contractor may not be ableto monitor the weld repairs as they are being made at therolling mill to verify that they are being performed to therequirements of the code. For these reasons, weldedrepairs to FCM Material under the provisions ofAASHTO M160M [M160] (ASTM A 6M [A 6]) are notallowed at the producing mill.

C-12.4.4 Optional Base Metal Requirements. Specialmaterial requirements described in the contract docu-ments that are not normally provided by the steel pro-ducer should be described in the mill order so that themill is aware of all metallurgical and physical propertyrequirements before production begins. Listing of allspecial requirements on the mill order also provides theEngineer, Contractor, Inspector and other interested per-sons with verification that all FCM material require-ments have been understood and satisfied.

C-12.4.4.1 Optional Through-Thickness and Low-Sulfur Requirements. Lamellar tearing is defined asthe separation or tearing on planes parallel to the rolledsurface of the base metal from strains induced by weldmetal shrinkage in the through-thickness direction.Lamellar tearing occurs in the through-thickness direc-tion because the base metal has limited ductility in thatdirection. With strains applied in the through-thickness(Z) direction of thick members, the Engineer shouldevaluate each location and determine if improvedthrough-thickness (Z) properties should be required atspecific locations. If possible, the Engineer should pro-vide alternate details to eliminate through-thicknessloading, especially on thick plates. Normally, sulfidesare the most detrimental type of inclusions that contrib-ute to lamellar tearing, however, silicates and aluminamay also influence susceptibility to lamellar tearing.Base metal with low sulfur (less than 0.010%) andimproved through-thickness properties can be specified,typically at an increased cost. Locations in a structurewhere this type of material is required are to be identified


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on the contract drawings or specified in the contract doc-uments, and shown on the shop drawings.

C-12.4.4.2 Optional Heat Treatment. Material per-formance properties such as the notch toughness andstrength of the completed weldment and base materialwill normally be affected by heat treatment. It is theresponsibility of the Engineer to understand these effectsand specify what, if any, heat treatment is required sothat the material and completed member will performsatisfactorily.

C-12.4.5 Toughness. The notch toughness requirementsfor steels used in highway bridges were adopted after con-siderable research and deliberation between representa-tives of the AASHTO Subcommittees on Bridges andMaterials, the Federal Highway Administration, the Amer-ican Iron and Steel Institute, the American Institute ofSteel Construction and various consultants. These require-ments have been based on numerous technical consider-ations that include the following:

(1) the effects of constraint and temperature on thefracture toughness behavior of steels, established by test-ing fracture mechanics specimens.

(2) the effects of loading rate, number of load cyclesand the load intensity on the fracture toughness behaviorof structural steels.

(3) the relationship between impact fracture tough-ness values, obtained by testing fracture toughness typespecimens under impact loading, and impact energyabsorption for CVN test specimens.

(4) specification of CVN test values that ensure elas-tic-plastic initiation behavior for fracture of fatiguecracked specimens subjected to minimum operating tem-perature and the maximum in-service rate of loading atthe minimum operating temperature.

(5) verification of the selected toughness values byfull-scale fatigue testing of fabricated bridge girders thathave already reached their design service life by apply-ing the maximum in-service rate of loading at the mini-mum operating temperature.

(6) an understanding of the factors that have occa-sionally led to brittle behavior, including crack initiationand propagation in steel bridge members well beforereaching their expected service life.

C-12.4.5.1 Supplementary Requirements. Thematerial toughness requirements of this Fracture ControlPlan should be satisfactory for most applications. Forthose instances where special toughness requirements arenecessary, the Engineer is responsible to identify individ-ual components or connections in the contract drawingsand documents. The Engineer should not specify tough-

ness properties different from those required in this Frac-ture Control Plan, except when necessary for anticipatedsevere exposure, loading or other unique conditions.

C-12.4.5.2 Mill Orders. Base metal toughness forFCM components is a requirement of this code. Basemetals are to satisfy to the minimum applicable CVN testvalues specified by AASHTO M270M [M270] (ASTMA 709M [A 709]). The mill order is to specify the CVNtest values required. Plate frequency testing requires thateach plate is heat number-identified by the mill, with thecorresponding number and the CVN test values shownon the mill test report.

C-12.4.6 Base Metal Identification. Die stamp impres-sions can cause stress concentrations that could lead tofatigue cracking. For this reason, only low-stress or mini-stress die stamps are allowed. The imprint in the steelshould be as light as is practical to still allow easyreading.

C-12.5.1 Approved Processes. Structures welded bySMAW, SAW, FCAW, and GMAW with metal coredelectrodes processes using low hydrogen practices andmethods compatible with the fabricator’s shop equip-ment and expertise have a long history of satisfactoryservice. These processes are routinely used for produc-tion welding when high levels of toughness and qualityare required.

C-12.5.2 Prohibited Processes and Procedure Restric-tions. GMAW may be used when approved by the Engi-neer. GMAW may be performed using a variety ofmodes of transfer including spray, globular, pulsed arc,and short-circuiting transfer. Short-circuiting transfer,also called short arc or dip transfer, is a low energy modeof transfer. While ideally suited for sheet metal applica-tions (often less than 1 mm [1/32 in] thick and typicallyless than 6 mm [1/4 in] thick), it may lead to a conditionwhere fusion to the base materials is not achieved. Thisis typically called cold lap, unacceptable because nofusion exists between the weld metal and the base metal.For thin material applications, the energy input needs tobe controlled to avoid burn-through, and short circuitingtransfer is appropriate for these conditions. Whenapplied to heavier materials such as those typically usedfor bridge applications, special precautions need to beimplemented to preclude the development of these fusiondiscontinuities, including the cleanliness of the material,the proper selection of shielding gases, welder technique,etc. Root passes in open root joints (which are typicallynot applied to most bridge applications, but may beincorporated into bridges that utilize tubular members),are commonly made with GMAW-S.

Subclause 1.3.4 requires the Engineer’s approval for theuse of GMAW-S for all applications. For Fracture Criti-


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cal Members, the Engineer’s approval is required for allGMAW WPSs, regardless of mode of transfer. Thisallows the Engineer to carefully evaluate the exactparameters that will be used to ensure that the resultantweld quality will meet code and specification requirements.

GMAW may be performed with either solid electrodes orwith tubular electrodes that contain metal powders. Thesecond type of electrode is typically called a metal-coredelectrode. When initially introduced in the late 1970s,metal-cored electrodes were originally classified as fluxcored electrodes for FCAW-G welding. As such, theywere used for bridge applications and other structuralapplications through the 1980s and early 1990s. TheAWS A5 Filler Metal Committee determined that it wasmore appropriate to classify the welding performed withmetal-cored electrodes as GMAW, as compared toFCAW, because metal-cored electrodes did not leavebehind the residual slag blanket consistent with theFCAW process. Typical metal-cored electrodes nowhave classifications such as E70C-6, where the “C” des-ignates a cored electrode. Formerly, the same electrodeswere typically classified as E70T-1 flux cored elec-trodes. A Contractor welding with metal-cored elec-trodes currently requires the Engineer’s approval, butwhen this was previously considered FCAW, the Engi-neer’s approval was not required.

C-12.6.1 Heat or Lot Testing. Tests required to classifywelding consumables, which consist of electrodes, orelectrodes used in combination with fluxes or shieldinggas, or gas combinations, are specified in detail in theAWS Filler Metal Specification series designated A5.XX.The tests required by the A5 specifications, performedby the filler metal manufacturer, are designed to allowclassification of, and to demonstrate the capability of, thevarious consumables to produce sound welds with therequired mechanical properties when welding is doneunder the specified test conditions. Filler metals aretested using specific, uniform procedures so that theresults of common tests can be compared.

Subclause 12.6.1 requires the manufacturer of the weld-ing consumables to perform heat or lot testing to demon-strate conformance to the A5 requirements. TheContractor provides certified copies of all pertinent testreports to show evidence that the electrodes furnishedconform with all provisions of the AWS filler metalspecifications and the FCP. The tests represent the elec-trodes used in the work. Accepted heats and lots of weld-ing consumables that conform to the same specificationand are made by the same manufacturer may be inter-changed without concern that different combinations willadversely affect the quality of the weld metal produced.

C-12.6.1.1 Exemptions. Filler metal manufacturersthat produce filler metal products under a continuing qual-ity assurance program, audited and approved by one ormore of the agencies described in 12.6.1.1, have proventhat their quality is consistent, and may provide standardproducts that are not required to be heat or lot tested. Cer-tified copies of compliance by the auditing agency is ade-quate to verify conformance with this subclause.

C-12.6.2 Diffusible Hydrogen of Weld Metal. Theresistance to brittle fracture of a welded connection isdependent upon eliminating conditions that might rea-sonably be anticipated to lead to the initiation of cracks.The Fracture Control Plan limits the addition of unac-ceptable levels of diffusible hydrogen during the fabrica-tion of fracture critical members or member componentsby controlling minimum preheat and interpass tempera-tures and regulating the type and handling of consumables.

C-12.6.2.1 Testing. In addition to the usual mechani-cal tests and chemical analysis required by the fillermetal specification, the filler metal manufacturer willdetermine the hydrogen content of deposited weld metal,except for the SMAW process. This, along with properelectrode storage and baking of the submerged arc flux,is to minimize hydrogen cracking from the welding con-sumables. The glycerin method of determining the dif-fusible hydrogen content has been replaced by the gaschromatograph method or the under-mercury method, asdescribed in AWS A4.3. Research has shown that glyc-erin absorbs some of the hydrogen given off by the weldmetal. As a result, the newer test methods often generatehigher values for diffusible hydrogen when compared tothe glycerin test.

C-12.6.2.2 Electrode Optional Supplemental Mois-ture-Resistant Designator Requirements for TackWelding. Tack welds made without preheat may have anincreased tendency to crack due to the faster cooling rate,higher HAZ and weld metal hardness, and the increasedamount of diffusible hydrogen. The use of hydrogen con-trolled electrodes described in this subclause will furtherreduce the probability of cracking in the HAZ and in theweld metal (see C-12.13).

C-12.6.2.3 Electrode Optional Supplemental Moisture-Resistant Designator Requirements for Welding. The“H” designator indicates the maximum average diffusiblehydrogen content in milliliters per 100 grams (mL/100 g)of deposited weld metal. H4 means a maximum of 4 mL/100 g and H16 means a level of 16 mL/100 g. Higherstrength steels have a higher risk of hydrogen-inducedcracking, therefore higher strength weld metal requireslower diffusible hydrogen levels for this Fracture ControlPlan.


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C-12.6.2.4 Special Requirements. Special provi-sions that a filler metal manufacturer may require toensure that weld metal will meet the diffusible hydrogenrequirements of this code and the Fracture Control Planmay not be covered in this code. All additional require-ments or special precautions required by the filler metalmanufacturer in excess of those required in this code aredescribed in complete detail in a written procedure.

C-12.6.4.1 Matching Strength Groove Welds.When matching strength filler metals are required, thecode requires that the minimum notch toughness of thefiller metal be as described in Table 12.1.

C-12.6.4.2 Undermatching Strength Welds. Whenmatching strength filler metal is not required, the Engi-neer is encouraged to use, where appropriate, lowerstrength, high ductility weld metal that will reduce resid-ual stress, distortion, and the risk of cracking or lamellartearing in adjacent base metal HAZs. The code requires aminimum notch toughness of the undermatching strengthfiller metal of 34 J @ –30°C [25 ft∙lb @ –20°F]. Under-matching is most often associated with fillet welds onsteels with a minimum specified yield strength greaterthan 345 MPa [50 ksi].

C-12.6.5.1 SMAW Electrodes. SMAW electrodesare to be purchased in hermetically sealed containers forfracture critical work. If low hydrogen SMAW elec-trodes are furnished in hermetically sealed containersand the containers are undamaged, the electrodes shouldprovide acceptable low hydrogen performance when thecontainers are opened and the electrodes are used with-out prolonged exposure to the atmosphere. Instructionsfor the proper care and storage of electrodes are providedin this Fracture Control Plan.

C-12.6.5.2 Sealed Containers. A hermetically sealedcontainer is defined as a container that has been closed ina manner that provides a nonpermeable barrier to thepassage of air or gas in either direction. If the hermeticseal is damaged, the electrodes will not be protectedfrom exposure to the atmosphere and may absorb atmo-spheric moisture, and therefore cannot be used to makefracture critical welds. Redrying of electrodes from con-tainers with damaged hermetic seals is prohibited forFCM welding. The risk that drying electrodes that haveabsorbed excess moisture may not completely restore theelectrode coating to the original manufactured conditionis too great. They may be used for nonfracture criticalmembers. Electrodes with damaged flux coatings willnot provide proper shielding during welding and shouldnot be used for any welding, whether on fracture criticalor nonfracture critical members.

C-12.6.5.3 Storage. Once removed from hermeticallysealed containers, SMAW electrodes not used within the

time limits of 12.6.5.6 through 12.6.5.9 are placed in anoven and held continuously at a temperature of at least120°C [250°F] until removed for use. At that tempera-ture, the electrode coating will not pick up moisture fromthe atmosphere.

C-12.6.5.4 Drying Temperatures. SMAW electrodecoatings are to be kept clean and dry, requiring the use ofelectrode drying and storage ovens. Ovens used for stor-age are to be above 120°C [250°F] and below 290°C[550°F]. Ovens used for drying are to be above 230°C[450°F] and below 290°C [550°F]. Should the oven tem-peratures drop below the specified values, it is allowableto restore the electrode’s coating by drying at tempera-tures between 230°C and 290°C [450°F–550°F] for thespecified period. Electrodes that have dropped belowthese temperatures for excessive periods of time mayhave picked up excessive moisture, and attempting torestore these electrodes to their original condition maynot be a suitable risk.

Electrodes may be redried only once. Repetitive dryingoxidizes metallic elements in the coating, and may causecracking or failure of the coating. Low hydrogen elec-trodes that are not acceptable for use under the provi-sions of this Fracture Control Plan, because of theirexposure to the atmosphere, can be used for nonfracturecritical applications if allowed as described in 4.5.

For carbon steel low hydrogen electrodes, AWS A5.1/A5.1M, Specification for Carbon Steel Covered ArcWelding Electrodes, specifies a maximum moisture con-tent in the as-manufactured or as-received condition forlow hydrogen coatings of no more than 0.6% for E70XX,0.3% for E70XX-R, and 0.1% for E70XX-M. Alloy steellow hydrogen electrodes covered in AWS A5.5/A5.5M,Specification for Low Alloy Steel Covered Arc WeldingElectrodes, also have a specified maximum moisturecontent in the as-manufactured or as-received condition.For the E70XX-X class electrodes, it is 0.4%; for E70XX-R, 0.3%; for E80XX-X electrodes, 0.2%; and for theE90XX-X, E100XX-X, E110XX-X class electrodes,0.15%.

Experience has shown that the limits specified above formoisture contents in electrode coverings are not alwayssufficiently restrictive for some applications using theE90XX-X and lower classes. Electrodes of classifica-tions lower than E100XX-X are subject to more stringentmoisture level requirements when used for weldingGrade 690/690W (100/100W) steels. All such electrodesare dried between 370°C and 425°C [700°F–800°F] forone hour before use (see 4.5.3). Electrodes of classifica-tion below E90XX-X are not required by AWSA5.5/A5.5M to have a moisture content less than 0.15%,and the required drying will achieve at least this moisture


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level. This precaution is necessary because of the sensi-tivity of high strength steels and weld metal to hydrogen-induced cracking.

C-12.6.5.5 Storage Ovens. Opening the electrodeoven door to check the temperature of the electrodes willresult in somewhat lower readings than actually existwithin the oven with the door shut. If an excessive tem-perature variation occurs because of an unsealed or opendoor, and high drying or baking temperatures are beingused, the temperature gradient may cause the electrodecoating to crack. If the temperature gradient is excessiveand the baking or drying temperature is high, there maybe damage to the electrode flux coating. Using the porthole in the oven door or a thermometer that allows directtemperature readings of the inside oven temperature willallow accurate readings. No material other than elec-trodes should ever be placed in a storage or holdingoven, since contamination of the rods could result.

C-12.6.5.6 Maximum Atmospheric Exposure ofSMAW Electrodes. Table 4.7 lists the maximum allow-able time that electrodes can be exposed to the atmo-sphere. Longer exposure times may lead to excessivemoisture pickup by the electrode coating. Exposure timeis based upon the strength level of the electrode. Higherstrength weld metal will tolerate less hydrogen thanlower strength weld metal. Electrodes with the optionalsupplemental moisture resistance designator “R” may beexposed to the atmosphere for a longer time period asgiven in 12.6.5.8.

Tests have shown there can be a wide variation in themoisture absorption rate of various brands of electrodesrepresenting a given AWS classification. Some elec-trodes absorb very little moisture during standard expo-sure times, while others absorb moisture more rapidly.The moisture control requirements of Table 4.7 are nec-essarily conservative to cover this condition and ensurethat sound welds can be produced.

The time restrictions on the use of electrodes after removalfrom a storage oven may seem overly restrictive to someusers. The rate of moisture absorption in areas of lowhumidity is lower than that encountered in areas of highhumidity. The code covers the most restrictive situations.

C-12.6.5.7 Electrode Exposure Limit. Under certainconditions, standard and moisture resistant electrodesmay be dried in a drying oven and reused. Drying isallowed only for electrodes removed from the oven for atime period less than the allowed exposure time, or forelectrodes stored in an oven temporarily below the mini-mum specified holding temperature of 120°C [250°F](see 12.6.5.4). No electrodes may be dried for fracturecritical work that have exceeded the exposure timesdescribed in Table 4.7 or 12.6.5.8. SMAW electrodes can

be redried only once before use. Rod ovens are to haveseparate areas for rods received directly from containersand those being redried.

C-12.6.5.8 Optional Supplement Moisture-Resis-tant Designators. In order for a low-hydrogen electrodeto be designated as low-moisture-absorbing with the “R”suffix designator, electrodes are to be tested by exposureto 27°C and 80% relative humidity for a period of notless than 9 hours. These tests are defined in AWS A5.1/A5.1M and A5.5/A5.5M, and are conducted by the elec-trode manufacturer. The nine hour time period wasselected based upon a typical workshift length, includingmealtime. The moisture content of the exposed coveringis not to exceed the maximum specified moisture contentfor the “R” designated electrode and classification in theappropriate A5.1/A5.1M or A5.5/A5.5M specification.Such electrodes may be used with exposure times of upto nine hours on steels with a minimum specified yieldstrength of 345 MPa [50 ksi]. For higher strength steels,exposure time is limited to that described in Table 4.7.

C-12.6.5.9 Electrodes for Grades HPS 485W [HPS70W], 690/690W [100/100W] Steels. When used forfracture critical Grade HPS 485W [HPS 70W], Grade690 [100], and Grade 690W [100W] steel members, thissubclause allows redrying electrodes exposed for periodsexceeding the limits of Table 4.7 by one hour or less. Thehigher redrying temperature range of 425°C to 540°C[800°F–1000°F] is sufficient to restore the electrodecoating to a low moisture level, provided the electrodeswere not damp and the ambient atmospheric exposuretime was no more than one hour beyond the limits ofTable 4.7.

C-12.6.5.10 Production Welding Electrode Usage.How much moisture is absorbed or adsorbed (adheres tothe outside but is not absorbed) by the electrode coatingdepends upon the temperature, humidity, storage condi-tions, and the type of coating of the electrode. Electrodesin small containers open only at the top are partially pro-tected. They will pick up considerably less moisture thanelectrodes laying unprotected on cold, damp, or dirtysteel. Electrodes need to be kept in containers that pro-tect them from contaminants that would make the elec-trodes unacceptable for use. To reduce the chance ofelectrodes being exposed beyond the time limits of Table4.7, the welder is not allowed to remove more electrodethan will be consumed within these limits. The shopshould maintain written documentation of the timeswhen rods were taken and when rods were returned forredrying.

C-12.6.6.1 Diffusible Hydrogen. The “H” designatorindicates the maximum average diffusible hydrogen con-tent in mL/100 g of deposited weld metal. H4 means


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4 mL/100 g and H16 means 16 mL/100 g. For steels witha specified minimum yield strength of 345 MPa [50 ksi]or higher, only H4 and H8 are allowed, and H16 isallowed only for lower strength steels. Higher strengthsteels have a higher risk of hydrogen-induced cracking;therefore higher strength weld metal requires lower dif-fusible hydrogen levels under this Fracture Control Plan.

C-12.6.6.2 Electrode and Flux Packaging. Elec-trodes and fluxes that have been removed from their pro-tective packaging need to be protected from deteriorationand contamination prior to and during their use. Fluxeshave to be packaged in moisture resistant packages only,not hermetically sealed containers. Flux manufacturersmay provide hermetically sealed containers; however, itis not mandatory. If the flux package has been damagedor left open for long periods, the flux will not be pro-tected from prolonged exposure to the atmosphere, andtherefore is not allowed to be used to make fracture criti-cal welds.

C-12.6.6.3 Flux Handling and Drying (Baking).Proper storage and usage practices help ensure that fluxwill remain in a good, dry condition until used. Flux inundamaged packages stored in a protected dry environ-ment is generally expected to remain in good conditionuntil used, provided the time held in unopened bags isnot excessive. However, it is still mandatory to bake theflux dry to remove any possible excess absorbed mois-ture. After the package has been opened, exposing theflux to the atmosphere, the flux is to be stored, handledand distributed as described in this subclause for use onfracture critical members.

C-12.6.6.4 Drying and Storage Temperatures. Fluxovens are to be capable of storing and drying flux to therequirements of this Fracture Control Plan. The moistureis to be able to escape from the flux layer and not betrapped within the flux. If the flux layer is too deep, themoisture will not be able to vent to the surface of the fluxlayer and escape into the atmosphere. Flux consistencymay also be affected by uneven drying. Opening the fluxdrying or storage oven door to check the temperature ofthe flux oven will result in lower readings than actuallyexist within the oven with the door shut. Checking thetemperature through the port hole in the oven door orwith a thermometer that allows direct temperature read-ings of the inside oven temperature will allow accuratereadings.

C-12.6.6.5 Discharge and Refill of Flux Hoppers.Flux in hoppers of welding machines can pick up mois-ture if left in the equipment for an extended period oftime. How much moisture might be accumulated byabsorption or adsorption (moisture on the outside of par-ticles that do not absorb moisture) depends upon the tem-

perature, exposure conditions, relative humidity and fluxtype. Most fluxes are relatively unaffected by moisture,but it is poor practice to resume welding with old fluxstill in the hopper after a considerable delay. The 10-hourrule was established to prevent continuation of weldingwith existing flux left in the hopper after the machine hasbeen shut down for more than one shift. The time limitwas selected so that the flux did not have to be replacedafter suspension of welding during a shift, providedwelding with the same machine would resume before the10 hours had expired.

For example, removal and replacement of flux is not nec-essary if a machine is consistently in use for two (2) shiftsper day, but would be required if the shop is working onlyone shift per day, or suspending work for a weekend.

C-12.6.6.6 Open Top Flux Systems. Open top fluxhoppers allow the atmosphere to be in contact with thetop layer of flux without any protection being provided.The top layer (10 mm [3/8 in]) of flux, which maybecome contaminated if exposed over six hours, is to beremoved. Removal is to be done carefully, using either avacuum system or appropriate tool to avoid mixing thetop layer with the flux below.

C-12.6.6.7 Time Limits for Flux Replacement.With the approval of the Engineer, the flux exposuretime limits may be extended if the Contractor or manu-facturer can demonstrate by testing in conformance withthe provisions of AWS A4.3 for diffusible hydrogen thatthe limits have not been exceeded. The amount of hydro-gen absorbed is dependent upon many factors, includingbut not limited to temperature, relative humidity and theflux hopper system. If test welds made using extendedexposure fluxes verify that the diffusible hydrogen forthe welding procedure to be used conforms with theoptional diffusible hydrogen designator of the fillermetal and flux being used, then the exposure time limitsmay be extended, but the criteria for this extension needsto be fully defined, based upon those parameters used forthe test.

C-12.6.6.8 Pneumatic Flux Delivery Systems.Unless removed by dryers and filters, compressed airmay contain moisture, oil, and other contaminants whichcan mix with the flux as the air moves the flux throughthe system. Only clean, dry air should be used to operatepneumatic flux delivery systems. Filtered, dried airshould be periodically checked by venting to the atmo-sphere to verify that it is acceptable for use. To avoid plac-ing moisture or contaminants in the joint, the air should notbe aimed directly at the weld joint when venting is done.

C-12.6.6.9 Flux Recovery. Contractors are allowedto recover and reuse flux that has not been melted or con-taminated by dirt, moisture, or any other material that


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will adversely affect welding properties. Flux removedimmediately after welding is still hot and dry and may bedirectly recycled into the system. Before use in produc-tion welding, flux not recovered from weldment surfaceswithin five minutes but recovered within one hour is tobe dried at 290°C [550°F] for at least two hours, or fol-lowing the temperatures and times recommended by theflux manufacturer, to remove any moisture. Flux thatfalls on the floor or comes into contact with oily steelsurfaces is not to be reused because of likely contamina-tion. All reclaimed flux should be passed throughscreens, and magnets where appropriate, to remove millscale and other debris.

C-12.6.6.10 Recovered Flux. When fluxes are recov-ered, they may break into smaller particles as part of themechanical process of removing the flux from the weldjoint and replacing this recovered flux into the flux stor-age system. Some flux recovery systems will separateflux fines (often called flux flour) out of the system.These fine particles may be of different chemical compo-sition than the bulk of the flux. Excessive flux fines mayaffect bead shape. Significant differences in compositioncould affect weld metal mechanical properties. This pro-vision requires that any harmful effects of flux recoverybe mitigated by requiring that at least 1/3 of the total fluxused be new, properly dried material. The method usedby the Contractor needs to be defined in a written docu-ment, and followed by the welding operators.

C-12.6.6.11 Gravity Feed Delivery Systems. TheContractor adds new, unused flux in sufficient amountsto make up for all losses. To conform to this requirementin gravity fed systems, at least one-third new flux, byvolume, is added to the flux hopper at intervals not toexceed one hour during actual welding.

C-12.6.7.1 Diffusible Hydrogen. The “H” designatorindicates the maximum average diffusible hydrogen con-tent in mL/100 g of deposited weld metal. H4 means4 mL/100 g and H16 means 16 mL/100 g. For steels witha specified minimum yield point higher than 345 MPa[50 ksi] or higher, only H4 and H8 are allowed, and H16is allowed only for lower strength steels. Higher strengthsteels have a higher risk of hydrogen-induced cracking;therefore higher strength weld metal requires lower dif-fusible hydrogen levels under this Fracture Control Plan.

C-12.6.7.2 Electrode Packaging. FCAW electrodesthat have been removed from their protective packagingare to be protected from deterioration and contaminationprior to their use. FCAW electrodes have to be packagedin moisture resistant packages only, not hermeticallysealed containers. Manufacturers may provide electrodesin hermetically sealed containers; however, it is not

required under this FCP. If the package is damaged orleft open for long periods, the hydrogen content may beaffected because the flux core, through the electrode’sseam, may have absorbed a limited amount of moisturethat could introduce excessive hydrogen into the weld.

C-12.6.7.3 Shielding Gas. It is essential that the gasor gas mixtures used to shield FCAW-G be dry. Even aslight amount of moisture in the shielding gas may leadto porosity or hydrogen contamination of the weld. Toensure that the shielding gases are dry, a very low dewpoint is specified. If there is insufficient moisture in thegas to condense at a temperature of –40°C [–40°F], thegas is dry enough to be used in welding. A dew point of–40°C [–40°F] converts to approximately 128 parts permillion (ppm) by volume of water vapor, or about 0.01%available moisture. In addition to certifying conformanceto the dew point requirement of the specifications whenrequested, the Contractor furnishes certification that thegas or gas mixture is suitable for the intended weldinguse, and is the same gas used for WPS QualificationTesting. These provisions are identical to those of 4.13,except that the manufacturer’s certification is required.

No drafts in excess of 8 km/hr [5 mi/hr] are allowed withFCAW-G. Higher velocities may disperse the shieldinggas, allowing nitrogen, oxygen, and moisture from theatmosphere into the weld.

C-12.6.7.4 Electrode Storage. Electrodes are to bedry and clean when they are used. Electrode manufactur-ers package their electrodes in a manner that is intendedto allow them to be stored for reasonably extended peri-ods of time without damage from moisture or other con-taminants. Once removed from the plastic envelope, theelectrodes may pick up moisture, become contaminatedby foreign material, or rust. Electrodes that have rustedare unsuitable for welding and should be discarded.

Electrode manufacturers attempt to make their tubularelectrodes as impervious to moisture absorption as possi-ble. When welding is interrupted for more than 8 hours,electrodes are removed from the welding machines andeither returned to protective packaging or placed in astorage oven until again needed. After accumulating 24hours of exposure, the electrodes are to be reconditionedas required in 12.6.7.6. An identification and monitoringprocedure preventing over-exposed electrodes frombeing used on fracture critical welds is necessary.

C-12.6.7.5 Time Limit Extension for ElectrodeExposure. With the approval of the Engineer, theFCAW electrode exposure time limits may be extendedif the Contractor or manufacturer can demonstrate bytesting, in conformance with the provisions of AWSA4.3, that the diffusible hydrogen limits have not been


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exceeded. The amount of hydrogen absorbed is depen-dent upon many factors, including but not limited to tem-perature, relative humidity, shop conditions and how theelectrode is packaged, stored, and handled. If tests onover-exposed wire verifies that the diffusible hydrogenfor the WPS to be used conforms with the diffusiblehydrogen designator of the filler metal being used, thenthe exposure time limits can be extended, but the criteriaare to be fully defined, based upon test conditions.

C-12.6.7.6 Drying Temperatures. FCAW electrodesare to be kept clean and dry, requiring the use of elec-trode drying and storage ovens for holding the electrodesafter they have been removed from their protective pack-age and have exceeded the exposure time limits asdescribed in 12.6.7.4. Only metal reels are recommendedunless it can be shown that other type reels are not dam-aged by the baking temperature. Ovens used for bakingare to be above 260°C [500°F], but not exceed 290°C[550°F]. Electrodes may be baked only once. Repetitivebaking may cause failure of the flux system. If thebaking requirements of 12.6.7.6 are in conflict with theelectrode manufacturer’s recommendations, the manu-facturer’s recommendations take precedence.

C-12.7 Welding Procedure Specification (WPS)

Current AWS filler metal specifications recognize thatweld metal properties may vary widely, depending uponelectrode size, flux used, current (amperage), voltage,plate thickness, joint geometry, preheat and interpasstemperature, surface condition, base metal composition,and admixtures with the deposited metal. Because of theprofound effect of these variables, a test procedure isincluded in the filler metal specifications requiring thesame welding conditions for all filler metal manufactur-ers. This provides a uniform basis to compare weld metalproperties to the minimum acceptance criteria set by theA5 Specifications. The welding parameters specified arenot representative of all possible production setting anddo not allow the producer to vary the current, voltage andtravel speed to optimize weld metal properties.

Although the A5 filler metals specification test require-ments are adequate for most applications, they are notconsidered sufficient for welding primary bridge mem-bers. Therefore, this code requires WPSs to be qualifiedby test as described in Clause 5 and as amended for Frac-ture Critical Members as described in Clause 12. Lowand intermediate strength SMAW WPSs for FCMs areexempt from qualification testing as described in 12.7.1of the code. WPS qualification tests help ensure that the

properties of the production weld metal deposited willprovide the strength, ductility and toughness required bythe code.

C-12.7.1 Limited Prequalification for SMAW. Underthe FCP, only the listed electrodes of E7016, E7018-1,and E8018-X, including those with “C,” “M,” and “R”designations, are considered prequalified. The E7028electrode has inadequate toughness for groove weldsunder the FCP.

Low and intermediate strength SMAW WPSs are exemptfrom testing because the methods used to weld in theshop or field are essentially the same as the methods andcontrol of welding variables used during the electrode’scertification tests. Qualification testing of high strengthSMAW WPSs adds an additional level of safety for highstrength welds. Under D1.5, electrode classification testsare run yearly and available for the Owner’s review asspecified in 4.5.5 and 5.5.

WPSs may use standard geometries of welded joints asdescribed in Clause 2, or use nonstandard joint geome-tries that have been qualified in conformance with 5.13.

C-12.7.2 Groove WPS Qualification. The WPS qualifi-cation tests described in this subclause, together with theprocedures for control of welding variables listed inClause 4, Part G, give confidence that welds will havethe mechanical properties, quality, and soundnessrequired by the code or contract documents. The CVNtest values are to satisfy 12.6.4 for this Fracture ControlPlan, rather than the requirements listed in Table 4.1 or4.2 that applies for the balance of the code.

C-12.7.3 Fillet WPS Qualification. Weld metal proper-ties for fillet welds are evaluated by testing groovewelds. Although currently under study through a TexasDOT⁄University of Texas/NSBA funded program, thereis no practical way at this time to measure the ductilityand toughness of small single-pass fillet welds. For thisreason, mechanical testing of fillet welds is not required.Adequate side and root fusion and the absence of internaldiscontinuities in fillet welds is verified through section-ing and macroetch tests. It is acknowledged that one- andtwo-pass fillet welds will have markedly differentmechanical properties than multi-pass groove welds.

C-12.7.4 Period of Effectiveness. Because of the natureof Fracture Critical work, a Contractor implementing anew WPS who has not performed the required WPSqualification testing to this or the previous FCP withinthe proceeding 12 months runs a WPS qualification testsatisfying this FCP. Subsequent qualification tests are tobe performed at the frequency described in this subclause.


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C-12.8 Certification and Qualification

Quality workmanship requires fabrication capability,trained workmen, and effective knowledgeable supervi-sion. The AISC Quality Certification Program evaluatesa fabrication plant’s general management, engineering,drafting, procurement, operations and quality control.Each of these areas is divided into sub areas and evalu-ated for policies, organization, personnel, procedures, facil-ities and equipment, and past record. AISC Major SteelBridges, previously known as Category III, with theFracture Critical Endorsement, helps ensure the shop’sability to produce FCMs.

C-12.8.1 Individual Competence. All individualsshould have prior experience in the work to be per-formed. Trainees or others without adequate experienceshould not be allowed to practice on FCM work.

C-12.8.2 Welding Personnel Qualification. The codeallows the qualification of welding personnel to remainin effect indefinitely for nonfracture critical welding,provided they have used the process within the past sixmonths. The Fracture Control Plan requires requalifica-tion at least annually or for each project. This require-ment is more restrictive than for groove welding ofnonfracture critical members. In order to keep the costsof annual requalification to a minimum, the Engineershould consider the option to base the annual requalifica-tion of groove welders/welding operators on acceptableradiography of production groove welds. Personnel mak-ing Fracture Critical fillet welds and tack welds are qual-ified in accordance with the standard requirements ofClause 5, Part B. Note that personnel who are qualifiedfor groove or fillet welding are also considered qualifiedfor tack welding.

C-12.9 As-Received Inspection ofBase Metal

Initial visual inspection of all received material is impor-tant and is intended to eliminate the possibility that adefective piece supplied by the producing mill willbecome a part of a fracture critical member or membercomponent. Subclause 12.4.3 prohibits the repair of dis-continuities found at the producing mill by welding, anda visual examination will identify these areas for repairper the requirements of 12.17. Visually inspecting thepiece for discontinuities before fabrication begins helpsto avoid later problems, especially if base metal defectsare found after welding has been completed, necessitatingcritical repairs and risking distortion of the weldmentduring the repair.

C-12.10 Thermal Cutting

This title was changed from “oxygen cutting” to “ther-mal cutting” in the D1.5-95 code because most mills andfabricating facilities can also perform plasma cutting. Itappears that plasma cut edges are equivalent to oxygencut edges; thus it seems proper to use the commongeneric term—“thermal cut edge” (TCE).

Surfaces and edges to be welded are expected to besmooth, uniform, and free from fins, tears, cracks andother discontinuities that might adversely affect the qual-ity or strength of the weld. When metal is cut by shear-ing, edges are often ragged and sometimes torn orcracked. Laminations at sheared edges sometimes splitapart. Sheared edges, because of their rough surface, aredifficult to inspect for cracks, laminations and otherharmful discontinuities that may propagate into a weldregion. Unwelded edges with such sharp notches couldhave reduced fatigue life. Universal mill plates mayexhibit similar unacceptable surface discontinuities.These stress risers left on unwelded tension memberedges may develop into fatigue cracks that could causethe piece to fail in service.

Thermal cut edges are generally superior to sheared edgesand avoid many of the conditions that can adverselyaffect the quality of the welds or reduce fatigue life.

C-12.10.1 Thermal-Cut Edge Requirements. SeeC-3.2 for a detailed explanation.

C-12.10.2 Magnetic-Particle Testing. The yoke methodof MT is specified because it avoids the possibility of themagnetizing current arcing the base metal at a prod con-tact point. Fatigue cracks may initiate from arc strikescaused by prods.

An adjustable probe is much more effective than a fixedyoke. Overall inspection is likely to be more thoroughthan with prods because the yoke is easier to manipulateand requires less strength and stamina to perform, impor-tant for an operator working for long periods of time.

C-12.10.3 Laminar Discontinuities. Laminations arenormally parallel to the rolled surface, appearing asplanes in the through-thickness of the piece. Laminationsexposed at the fusion face of a groove weld are essen-tially like a crack and may propagate into the weld orbase metal during weld cooling or in service. Becausethe depth of the lamination may be extensive, assumingthe lamination will be melted out or suitably fused andclosed by welding is not acceptable. If a laminationexists within 300 mm [12 in] of the weld on the edges ofthe member to be welded, there is the possibility that thewelding stresses or the application of design loads may


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cause the lamination to propagate into the weld metaland HAZ of the base metal.

Welding is prohibited across laminations on fracture crit-ical members or member components because there isthe possibility that weld discontinuities or cracks willresult.

C-12.11.1 Rotation of Base Metal. Because FractureCritical Members or member components require a highlevel of care when making repairs, base metal repairsshould not be made unnecessarily. It is preferable tocorrect the defect area by means other than welding, ifpractical.

C-12.11.2 Thermal Cutting. It is acceptable to removethe area of base metal that contains the defect by thermalcutting and to replace it with another piece of suitableapproved steel. The relocation of the butt joints fromtheir original detailed location or the addition of buttjoints needs to be preapproved by the Engineer. Theweld locations are to be documented and recorded onshop drawings submitted for the Engineer’s records. For amore detailed discussion on thermal cutting, see C-3.2.2and C-3.2.3 (see C-12.17 for repairs of base metal madeby welding).

C-12.11.3 Repairs. For a more detailed discussion, seeC-3.2.2 for base metal repairs and C-12.17 for base metaland weld metal repairs.

C-12.11.4 Replacement. Rather than repairing it, defec-tive base metal may be removed and replaced with newbase metal. The material may be of the same or higherstrength, with equal or superior toughness and weather-ing properties, except that Grades HPS 485W [HPS70W] and 690/690W [100/100W] are not to be substi-tuted for lower strength material. The substitution ofthese grades of quenched and tempered material forlower strength material would be such an overmatch thatit could cause residual stresses and cracking problemsdetrimental to the structure. All new base material andweld metal is expected to comply with the requirementsof this code and the Fracture Control Plan.

C-12.12 Straightening, Curving, and Cambering

Fracture Critical Members distorted by welding mayonly be straightened by heat-shrink (upset shortening)methods. For other than Fracture Critical Members, thecode allows mechanical methods such as press bendingor “cold gagging.” NCHRP research on the subject ofbridge repair has verified that less damage is done to thesteel by the carefully planned and executed use of heatstraightening than is typically done by mechanical

straightening using force alone. All straightening andcurving tends to reduce toughness and ductility of weldand base metal to some degree.

When heat straightening is performed, care is to be takento avoid overheating the steel. The maximum heatingtemperatures that are specified are very close to thetransformation temperature of the steel. Extreme careshould be exercised when trying to straighten highstrength Q & T steels, because heating beyond the maxi-mum temperature can cause loss of strength, toughnessand ductility.

C-12.13 Tack Welds and Temporary Welds

C-12.13.1 Tack Welds. Tack welds are given specialattention because they may be crack initiation sites.

C-12.13.1.1 Location. Properly made tack welds,located outside of weld joints, may constitute poor fatiguedetails. For example, intermittent tack welds on the out-side of longitudinal backing inside box sections constituteCategory E fatigue details. A continuous tack weld at thesame location is a Category B detail. The code requiresthat all tack welds be made within the weld joint, unlessspecifically allowed by the Engineer. A continuous tackweld for longitudinal backing would be one examplewhere the Engineer’s approval would be appropriate.

C-12.13.1.2 Requirements. Tack welds can be madeinappropriately, resulting in fabrication-related cracking.Tack welds are typically made with low heat-inputWPSs, typically small in size, and may be small inlength. Such welds experience high cooling rates, andcracking under such conditions may occur. Tack weldsthat are of insufficient size, whether too short or of toosmall a throat dimension, can crack due to shrinkagestresses, part handling, or subsequent expansion and con-traction of the final welding.

Table 12.2 lists four approaches that are allowed for tackwelding on FCMs. One involves tack welds outside theweld joint, and requires the Engineer’s approval (seeC-12.13.1.1 and Table 12.2, Note 4).

The first option contained in Table 12.2 is for tack weldsintended to be remelted by subsequent SAW. These tackwelds should be made small in size, and longer in length,in order to obtain the required strength, and to facilitatesubsequent remelting by SAW. The code does notrequire a test to demonstrate that such tack welds arebeing remelted by SAW. Moreover, it is acknowledgedthat other welding processes are capable of remeltingtack welds. A large tack weld with a substantial throatdimension is unlikely to be remelted by SAW. Addition-


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ally, welding over such large tack welds in the root of agroove can cause subsequent weld quality problems andmay affect weld appearance.

The WPSs for tack welds that are remelted by SAW neednot be qualified by test, but the filler metals used forthem conform to Table 4.1 or 4.2. SMAW electrodesused for tacking conform to 12.6.2. The reason for theomission of WPS qualification for these WPSs is two-fold. First, the subsequent submerged arc remelts andeliminates the tack weld, so its original properties are ofno consequence. Secondly, WPSs for tack welds (i.e.,small weld sizes) involve low heat input unable to gener-ate the code-mandated strength, elongation, or toughnessproperties of a WPS qualification test.

No preheat is required for tack welding when the tackweld is remelted by subsequent SAW. Even though thetack weld may be very high in hardness, low in elonga-tion, or may even crack, the remelting by subsequentSAW eliminates this condition.

GMAW may be used for tack welding when the tackwelds are remelted by SAW. Normally, with solid elec-trodes, GMAW welding requires the Engineer’sapproval for use on FCMs. Because these tack welds areremelted, no such approval is necessary.

The second tack-welding option allowed by Table 12.2treats the tack weld just like production welds. Preheat isrequired, the WPS is required to be qualified by test, theminimum weld sizes apply, etc. A minimum length of75 mm [3 in] is required in order to generate a minimumlevel of localized heating of the part.

The third option of Table 12.2 is essentially the same asthe second option, but deals with tack welds outside thejoint. These require the approval of the Engineer.

The fourth option is for tack welds inside the joints thatdo not conform to the conditions of the first two options.These tack welds are not remelted by SAW, nor do theymeet the minimum size requirements of the secondoption. A minimum preheat level of 200°C [400°F] isimposed for these types of tack welds to minimize thepotential of hydrogen-induced cracking, even with lim-ited heat input. These WPSs are to be qualified by testand experience has shown that it is unlikely that accept-able weld metal properties be obtained if very low heatinput WPSs are qualified. Therefore, the expectation isthat the fourth option will rarely be used.

C-12.13.2 Temporary Welds. Temporary welds arewelds made to attach a piece or pieces to a weldment fortemporary use in handling, shipping, or working on theweldment. Such welds and their HAZs may experiencestresses and stress ranges that may initiate fatigue cracks,

and therefore are to be removed. Temporary welds maybe allowed to remain in place if approved by the Engineer.

C-12.13.3 Weld Removal. Tack and temporary weldremoval sites may be sources of fatigue cracks inbridges. Fatigue cracks may initiate from HAZs andfrom discontinuities that remain in the steel, even thoughthe removal site is ground flush. Hydrogen-inducedcracks may also initiate at these locations. Weld removalalso includes removal of the shallow HAZ below theweld. Grinding to a depth of 3 mm [1/8 in] below theoriginal surface will remove all traces of sound tackwelds and their HAZs. Hydrogen-induced cracks, ifpresent, should be detectable on the surface and requirefurther exploration and repair. To keep stress risers to aminimum, a smooth transition is necessary, and the sur-face needs to be ground to a smooth finish.

C-12.14 Preheat and Interpass Temperature Control

Tables 12.3, 12.4, and 12.5 for preheat under the Frac-ture Control Plan have added two additional elements notconsidered for redundant members: the diffusible hydro-gen limit of the weld metal deposited by various fillermetals, and the heat input from welding. The level ofrequired preheat is therefore a function of the type ofsteel, thickness of steel, hydrogen level of the fillermetal, and the heat input from the welding process.

The grade of steel is one of the variables necessary todetermine the required level of preheat because as thecarbon content of the steel increases, or as the level ofalloy content increases, the degree of hardenability of thesteel also increases. The higher the hardenability, thegreater the level of required preheat to prevent cracking.

As the thickness of the steel increases, the rate of coolingexperienced by the weld in the HAZ also increases, allother parameters being constant. Increased cooling ratesmay lead to higher hardness of the HAZs and weldmetal, justifying increased levels of preheat. Reducedlevels of heat input from welding results in faster coolingrates, and justifies higher preheat to preclude cracking.

Finally, as the level of hydrogen in the deposited weldmetal increases, the susceptibility to hydrogen-inducedcracking increases. Conversely, lower levels of diffusiblehydrogen will reduce cracking sensitivity, allowing theuse of lower levels of preheat.

To arrive at the preheat tables that incorporate these twoadditional variables, the Committee began with the pre-heat values described in the 1978 Guide Specificationsfor Fracture Critical Non-Redundant Steel Bridge Mem-bers. The Guide Specification had provisions that would


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ensure that the allowed electrodes would deposit weldmetal with a diffusible hydrogen content that would notexceed approximately 10 mL per 100 g, as measured bythe glycerine method. This level of preheat, proven to beadequate by 15 years of fabrication experience, becamethe required preheat level for WPSs using a heat input of2.0 kJ/mm to 2.8 kJ/mm [51 kJ/in–71 kJ/in], and forweld deposits that did not exceed 8 mL/100 g, (H8)deposits. This was a conservative approach, since the1978 Guide Specification provisions did not ensure thatH8 weld metal could be achieved. In other words, thelevels of preheat were arbitrarily increased slightly, sincethe H8 requirement would provide lower levels of diffus-ible hydrogen than were required by the 1978 GuideSpecification. A comparison of the Guide Specificationvalues and the D1.5-95 values shows that the 2.0 kJ/mmto 2.8 kJ/mm [51 kJ/in–71 kJ/in], H8 requirements forthe given steel thickness and grade are identical to theGuide Specification requirements.

The Guide Specification values were then modifiedbased upon a preheat model established by Dr. Yuriokaof Nippon Steel. To begin the analysis with the Yuriokamodel, a chemistry is required to be known. From thechemistry, a “CEN” or Carbon Equivalency Number isdetermined. For the purposes of the code, however, theactual chemistry of the steel that would be employed isnot specifically known. Therefore, the time proven pre-heat levels of the Guide Specification, for the assumedheat input range of 2.0 kJ⁄mm to 2.8 kJ⁄mm [51 kJ/in–71 kJ/in], and the hydrogen level of H8, were used toback into the CEN value that would predict the preheatlevels that had been previously required in the guidespecification. To do this, 2.0 kJ/mm [51 kJ/in] heat inputswere used, and the lower level of the thickness range wasemployed. These two measures added in yet anotherdegree of conservatism into the calculations. Once theCEN value was established, the Yurioka model was usedto predict what increase in preheat would be required forlower levels of heat input (specifically 1.2 kJ/mm[31 kJ/in]), and what decrease may be allowed for heatinput levels of 2.8 kJ⁄mm [71 kJ/in] or higher. Thisapproach generated specific numbers that would be verydifficult to rationally control in a fabrication shop. Forthe D1.5-95 code, it was decided that the preheat levelswould be grouped into 14°C [25°F] increments. To dothis, the actual calculations were rounded down 5.5°C[10°F], or up 8.3°C [15°F] in order to develop even incre-ments of 14°C [25°F]. Overall, this approach addedanother level of conservatism to the calculations.

Using the Yurioka model, the nonrounded values wereused to predict the decrease in preheat that would beacceptable with H4 weld deposits, and the increase nec-

essary with H16 deposits. Once these values were estab-lished, the aforementioned rounding policy was used.

After all the values were put in a table, the Committeeexercised some judgment in adjusting numbers to fit amore logical sequence, rounding some figures up 14°C[25°F] in order to provide consistency and some techni-cally logical consistency between all the tables, addinganother degree of conservatism.

In some cases, the required preheat levels predicted bythe Yurioka models would have eliminated the need forpreheat beyond that of normal ambient conditions inmost fabrication shops (e.g., approximately 15°C[60°F]). However, this code specifies that, regardless ofthe predicted preheat, a minimum of 40°C [100°F]should be applied to all fracture critical fabrication. Anyvalue less than 40°C [100°F] were thus increased to thisminimum level. This added another level of conserva-tism to the preheat levels.

For AASHTO M270M [M270] (ASTM A 709M[A 709]) Grade 690 (100), and 690W (100W) gradesteels, it was determined that the highest level of diffus-ible hydrogen allowed should be limited to H8. For thisreason, Table 12.5 does not include the H16 category andH4 and H8 have been combined into one column.

It should be noted that the hydrogen groupings representthe maximum allowable level of diffusible hydrogen. Forexample, a filler metal capable of delivering weld depos-its with 6 mL of diffusible hydrogen per 100 g would beclassified as an H8. The preheat levels assume that thehydrogen level is at 8 mL per 100 g even though it islower than H8. The preheat is established for the maxi-mum allowable diffusible hydrogen level allowed for theparticular H classification. For the range of heat inputshown, the preheat level is established for the lowestallowable heat input. For the thickness ranges shown, thepreheat is based on the thickest material allowed in therange. The preheat is expected to be adequate when allvalues are at their extreme level. Lower levels of diffus-ible hydrogen, thinner sections, and higher heat inputWPSs within an allowable range will increase the levelof safety when the preheat values in the tables are used.

For the D1.5-96 code, new metric tables were developed.The allowable thickness ranges utilized appropriate met-ric increments of 20 mm [3/4 in] in thickness, and theheat input ranges were converted into a logical metricinterval of kJ/mm. It was determined that a preheat inter-val of 20°C [35°F] was logical. Rather than starting withthe U.S. Customary table that had rounding implicationsand other adjustments built into it, the calculated CENwas used to derive a true metric table. Actual calculatedvalues were rounded to the nearest 20°C [35°F]. incre-ment, and the values were adjusted for logical consistency.


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A minimum value of 40°C [100°F] was established as thelower bound for all fabrication.

C-12.15.1 Hydrogen Diffusion Postheat. Postheat isused to encourage the diffusion of hydrogen out of theweld and the HAZ. At elevated temperatures, the rate ofhydrogen diffusion is exponentially faster than at lowertemperatures. For example, approximately the samequantity of hydrogen will be diffused from a 25 mm [1 in]thick weld deposit in one hour when the weld is held at230°C [450°F] as would occur in two weeks at ambienttemperatures. When weld joints are large or severelyrestrained, when high strength steels are to be welded, orwhen other conditions suggest that hydrogen-inducedcracking or lamellar tearing could be a problem, post-heating may be considered. Postheat is required for FCMrepair welds in groove excavations [see 12.17.6 (11)].

C-12.15.1.1 Minimum Temperature Prior toHydrogen Diffusion Postheat. Hydrogen-inducedcracking only occurs at relatively low temperatures (lessthan 150°C [300°F] for most structural steels, less than250°C [480°F] for virtually all steels). To be effective,postheat is applied before the welded joint is allowed tocool below these temperatures. Otherwise, hydrogen-induced cracking can occur before the postweld heattreatment is applied, eliminating any beneficial effects ofthe treatment. For this reason, this provision requires thatpostheat be applied, when required, before the weldedjoint is allowed to cool below the minimum preheat andinterpass temperature.

C-12.15.1.2 Hydrogen Diffusion Postheat Temper-ature Limitations. Postheating effectively eliminateshydrogen-induced cracking from welds and HAZs. Steelthat is maintained at 230°C [450°F] or higher will con-tinue to diffuse hydrogen and reduce the risk of crackingeven if hydrogen levels and stress are higher than desir-able. However, since the exact temperature is not knownfor all steels and situations, the 230°C [450°F] tempera-ture and holding time is conservative.

C-12.15.2 Postweld Heat Treatment (PWHT).Heating of welds or base metal by external heatingsources to postweld heat treatment temperatures whichare 480°C [900°F] or higher is considered a postweldheat treatment (stress relief). Properly designed and con-structed bridge weldments have excellent fatigue liveswithout postweld heat treatment. Postheating at tempera-tures below 260°C [500°F] is primarily done to removehydrogen and is not considered a stress relief heattreatment.

C-12.15.2.1 Approval. Heating to elevated tempera-tures and cooling of steel weldments may detrimentallyaffect toughness and strength, and intergranular crackingmay sometimes occur in the grain-coarsened region of

the HAZ. It may also aggravate pre-existing discontinui-ties or allow new ones to form. It is essential that theEngineer approve postweld heat treatments so that theimpact on the ability of the member to function asdesigned can be assessed. Guidelines for stress reliefheat treatment are described in 4.4 of this code.

C-12.15.2.2 Controls. A detailed procedure listing allPWHT control items, including those in 12.15.2.2, thatare necessary to provide desired results needs to bedeveloped and submitted to the Engineer for approval.

C-12.15.2.3 Testing. If the bridge member is toreceive PWHT to stress relieve the weld and HAZ, or toimprove the weld’s mechanical properties by recrystalli-zation and transformation (austenitized), the WPS testplate(s) receives the same heat treatment before test spec-imens are removed by machining. Test specimensremoved from heat treated welds are not to be reheatedfor any purpose. Test methods, WPSs, and the test resultsindicating the effect of the PWHT on the complete assem-bly are to be submitted for the Engineer’s approval and toestablish that the member’s structural integrity should notbe compromised. Final required NDT is performed afterthe member has cooled to ambient temperature.

C-12.16.1.1 Inspectors. Individuals performinginspections and making decisions about the acceptabilityof materials and workmanship need documented evi-dence of qualification. Certification based upon success-ful completion of the AWS QC1 program, Standard forCertification of Welding Inspectors, is considered evi-dence of basic competence. Inspectors qualified as LevelII or III by the Canadian Welding Bureau in conform-ance with the provisions of CSA W178.2, Certificationof Welding Inspectors, are considered the equivalent ofan AWS Certified Welding Inspector, or CWI. Engineersand technicians who, on the basis of their educationand experience are considered equal to AWS or CWBcertified individuals in their ability to perform inspectionfunctions properly, may serve as inspectors with theEngineer’s approval.

The provision that allows engineers and technicians toact as inspectors, when approved by the Engineer,applies to both Contractor and Owner representatives. Itis intended to allow highly qualified individuals to per-form inspection functions, as necessary, even if they arenot certified by AWS or CWB (see 6.1.3).

Because of the critical nature of fracture critical memberwelds, this subclause requires that lead inspectors have aminimum three years of experience in bridge fabrication.To meet the requirements of this Fracture Control Plan, itis required that each lead inspector be familiar with andpersonally oversee the fabrication and NDT of eachFracture Critical Member under his or her control.


390

C-12.16.1.2 NDT Technicians. The code requirespersonnel performing NDT be certified as an NDT LevelII or Level III that has passed a practical examination andis also qualified as a Level II, in conformance withASNT Recommended Practice SNT-TC-1A. Theserequirements are more stringent than is required for NDTof nonfracture critical members by allowing the testingto be performed only by individuals certified as NDTLevel II and working under the supervision of a certifiedASNT Level III or by a certified Level III qualified as aLevel II. To ensure the capability of the Level III per-sons, they are required by code to be certified throughASNT testing or the testing equivalent as determined bythe Engineer. The term “under the supervision” meansthat the NDT Level III person will be available, as neces-sary, will personally oversee and independently verifythe NDT Level II technician’s work on a periodic basis.

C-12.16.2.1 Tension and Repaired Welds in ButtJoints. The Fracture Control Plan requires that both RTand UT be used in determining the quality of all groovewelds loaded in tension transverse to their axis. RT andUT are effective methods capable of inspecting the fullweld cross section. The effectiveness of RT and UT iscontingent upon the size, shape, and orientation of a dis-continuity. RT is effective in recording volumetricdiscontinuities and is also sensitive to planar discontinui-ties aligned with the inspecting radiation. UT is very sen-sitive to planar discontinuities normal to the inspectingsound beam. Both RT and UT are required to ensuredetection of discontinuities that may be missed if usingonly one of the NDT methods. The complementarystrengths of each method increase the effectiveness ofthe testing.

C-12.16.2.2 T- and Corner Joint Tension andRepaired Groove Welds. Radiographic inspection can-not be used effectively to examine T- and corner joints.Physical limitations on film and source placement pre-vent complete examination of the weld joint. UT doesnot have these limitations and is capable of inspecting T-and corner joints.

C-12.16.2.3 Fillet Weld Repairs. MT is a method ofinspection that complements visual inspection techniquesof fillet welds. MT also reveals near-surface discontinui-ties, but is primarily intended to be a surface inspection.MT inspection of fracture critical fillet weld repairs aidsa thorough visual inspection, as well as detecting near-surface discontinuities (see C-6.7.6 for a more detailedexplanation about MT).

C-12.16.3 RT Requirements. Verification of RT sensi-tivity and the acceptability of radiographs is based uponthe clarity of the Image Quality Indicators (IQIs) on thefilm. There are two types of IQIs accepted by the code

for nonfracture critical welds, the hole-type and the wireIQI. For fracture critical weld radiographs, only the hole-type IQI is allowed. The hole-type indicator providesadditional information regarding the RT image, includ-ing the presence of angular distortion of the imagecaused by placement of the source (see 6.10.7).

C-12.16.4 Cooling Times Prior to Inspections. As thejoint restraint and strength of steel increases, so does theconcern that hydrogen-induced cracking may occur.Restraint will be more severe in welds that are over50 mm [2 in] thick. Most hydrogen-induced cracks occurwithin the first 48 hours, even though they have beenknown to occur much later under some unusual condi-tions. The waiting periods described in this subclause areconsidered to be reasonable to ensure that hydrogen-induced cracks have had a chance to form, but are shortenough not to interfere unnecessarily with fabrication.Preliminary visual inspection may begin immediatelyafter the completed welds have cooled. RT may be per-formed immediately following cool-down to detect volu-metric discontinuities and early cracks, particularly in theweld metal. UT and MT will detect hydrogen-inducedcracking and therefore are subject to this time delay. Thefinal surface visual inspection is performed after thewaiting period.

C-12.16.5 Inspection and Record Keeping

C-12.16.5.1 Certified Reports. The inspector shouldensure that the Fracture Critical Members conform to therequirements of the contract documents. Detailed recordsare required in an effective fracture critical welding andfabrication inspection program. The Contractor isresponsible for the quality and necessary records of allNDT unless otherwise specified. The QA inspector maywitness NDT, review NDT reports and witness necessaryrepairs. NDT reports need to show what welds weretested and the results of each test. When critical repairsare necessary, a record of the repair and the NDT of therepair is necessary.

Fracture critical members or member components shouldhave inspection records for each individual piece, and alldocumentation developed during the fabrication of theFCM should be made a part of this record. Recordsinclude traceability of the material to the specific milltest reports, as provided by the Contractor’s materialscontrol system.

C-12.16.5.2 Identification of Inspectors. All inspec-tors, whether QA or QC that are part of the inspectionprocess for FCMs need to be identified in the records thatare kept as part of 12.16.5.1, including signatures anddates of acceptance.


391

C-12.17 Repair WeldingC-12.17.1 WPS Requirements. Repair welding is per-formed to the requirements of this Fracture Control Plan.This includes performing all welds to an approved WPS.WPSs may be preapproved for repairs classified as non-critical. Repairs classified as critical are to be fully docu-mented by the Contractor, including dimensions, NDTindications and proposed repair methods, and submittedfor the Engineer’s approval on an individual basis foreach repair. WPSs qualified for welding of FCMs neednot be requalified for repair welding, provided the jointdetail used allows access for welding.

C-12.17.1.1 Approval Procedures. Because the needfor repairs tends to be caused by typical discontinuities,such as lack of fusion, slag inclusions, porosity, under-size welds, lack of penetration, cracks, etc., it is accept-able to have preapproval by the Engineer of proceduresthat describe in detail how the repair is to be performed.

C-12.17.2 Noncritical Repair Welds. There are twoclassifications for repairs: noncritical and critical. Non-critical repairs, as described in this subclause, usuallyentail limited difficulty: increasing weld size for under-size welds, removing minor edge gouges, excavationsless than 65% of the weld size in depth, repairing under-cut, and base metal surface repairs.

C-12.17.2.1 Noncritical Repair Procedures. Becausenoncritical repairs share a number of common require-ments and utilize straight-forward methods for repair,procedures may be developed and preapproved withoutcase-by-case submittals. The procedure includes enoughdetail to allow the Contractor to make the repairs accord-ing to the requirements of this Fracture Control Plan. Sub-clause 12.17.6 lists the minimum provisions that theprocedure is to include. The use of preapproved repairprocedures may begin immediately upon verification bythe QA inspector that the procedure covers the intendedrepair (see 12.17.1.1).

C-12.17.3 Critical Weld Repairs. A critical repair asdescribed in this subclause requires the approval of the

Engineer before the repair can begin. Unless designatednoncritical in 12.17.2, all FCM repair welding is to beconsidered critical. Typical critical weld repairs includefabrication errors such as mislocated holes, repair ofdeep laminar discontinuities, repair of cracks in basemetal and weld metal, and repair of discontinuities thatrequire gouging more than 65% of the weld depth. Theprocedure includes specific detail which will allow theContractor to make the repairs according to the require-ments of this Fracture Control Plan, and documents thelocation of the discontinuity to be repaired. Subclause12.17.6 lists the minimum provisions to include in theprocedure.

C-12.17.4 Approval. Appropriate repair methods areessential for ensuring the integrity of the final structure,so all critical repairs need to be approved by the Engineerbefore the repair begins. If a noncritical repair becomescritical due to exceeding expected limits or defects in theinitial repair, the Engineer’s approval is necessary beforeproceeding. The procedure gives details of the type ofdiscontinuity, and location and extent of repair. The pos-sibility of cracking from residual stresses and distortionin repairs under high restraint should also be considered.

C-12.17.5 QA/QC Inspection. All repair welds are to beinspected to the original weld’s requirements, verifyingthe repaired weld is acceptable to the code and FCP. Thecooling times before final inspections may be performedas described in 12.16.4 also apply for weld repairs. TheEngineer may require additional inspections.

C-12.17.6 Repair Procedure Minimum Provisions.The minimum repair procedure provisions are includedin this subclause to provide the Contractor and Engineerwith adequate information to ensure a satisfactory repair,and to verify that the procedures are implemented. At aminimum, repair procedures are to include the itemsdescribed in this subclause, but additional measures maybe necessary to ensure acceptable results, especially fornontypical situations (high restraint, joints qualified bytest, etc.).



392


393

C-H2. Filler Metal RequirementsResearch conducted by the HPS Steering Committee andWelding Advisory Group for HPS 485W [HPS 70W]found that reduced preheat using filler metals with amaximum diffusible hydrogen level of 4 mL/100 g weretypically required to have a minimum heat input of40 kJ/in in order to meet the quality requirements of thecode. However, some filler metals were capable of pro-ducing acceptable quality weldments at lower heat inputs.

A limited number of filler metals were tested based onrecommendations of consumable manufacturers. OtherSAW filler metals may also produce acceptable qualityproduction welds, and should be allowed to be qualified

for welding HPS 485W [HPS 70W] when in conform-ance with the requirements of Tables 4.1 and 4.2.Research conducted at this time has suggested that certainFCAW and GMAW-Metal Core consumables selectedfrom the AWS classifications described in Tables 4.1and 4.2 may not consistently produce acceptable qualityweld metal. The Engineer should thoroughly evaluateother proposed consumables before allowing their use inthe work.

Specific manufacturers and consumables that haveconsistently produced acceptable quality welds are listedin the latest AASHTO approved Guide Specification forHighway Bridge Fabrication with HPS70W (see Annex N.)

C-Annex H

Welding Requirements for Conventional, Nonfracture Critical M270M [M270] (A 709M [A 709]) HPS 485W [HPS 70W]

Components with Reduced Preheat and Interpass Temperature



394

Index


395

AAASHTO/AWS

fracture control plan, 12, C-12interpass temperature control, 12.14,

C-4.2.1.2, C-12.14, Tables 12.3, 12.4, 12.5

temperature zone, 12.4.5, C-12.4.5, Tables 4.1, 4.2

Acceptance criteriabend tests, 5.19.2, 5.25.2, 5.26.2.1,

5.27.3macroetch test, 5.19.3, 5.26.3.4MT, 6.26.2per FCP, 12.3.3.2, C-12.3.3.2PT, 6.26.4RT, 6.26.2reduced section tension test, 5.15.1,

5.19.1stud welding, 7.8, C-7.8UT, 6.26.3, C-6.26.3.1, C-Tables 6.3,

6.4visual, 5.19.6, 5.27.1, 6.26.1

Air carbon arc processcutting, 3.2.6, C-3.2.6gouging, 3.2.3.3(2), 3.2.6, 3.7.1,

12.17.6(3), C-3.2.6, C-3.7.1Alignment, 3.3.3

jigs and fixtures for, 3.3.6, C-3.3.6offset, 3.3.3, C-3.3.3welds in butt joints, 3.3.3, C-3.3.3

Allowable stresses, 2.4, C-2.4All-weld-metal test, 5.16.3, 5.18.4,

5.19.4, Fig. 5.9Ambient temperature, 3.1.3, 4.2.6, 7.5.4,

12.16.4, C-3.1.3, C-7.5.4, C-12.6.4American Bureau of Shipping (ABS),

12.6.1.1(1)American Society of Mechanical

Engineers, (ASME), 12.6.1.1(3)Anti-spatter compound, 3.2.1, C-3.2.1Ancillary products, 1.3.6, C-1.3.6Application, 1.1, 7.6, C-1.1Approval of WPSs, 5.1

of weld repairs, 12.17.4, C-12.17.4

Arc shield, 7.2.2, 7.4.4, 7.4.6, Annex E, C-7.2.2, C-7.4.4, C-7.4.6

Arc strikes, 3.10, C-3.10ASNT Recommended Practice,

SNT-TC-lA, 6.1.3.4, C-6.1.3.4Assembly, 3.3, C-3.3Atmospheric corrosion resistance

base metals for, 4.1.4electrodes for, 4.1.4

Attachments, (FCM), 12.2.2.1,C-12.2.2.1

Attenuation, 6.19.6Attenuator, see Gain control

BBackgouging, 2.13.1, 3.2.6, 12.17.2,

12.17.3(2), C-3.2.6, C-12.17.2,C-12.17.3

air carbon arc, 3.2.6, 12.17.6(3),(6), C-3.2.6

chipping, 3.2.6, C-3.2.6grinding, 3.2.6, C-3.2.6

Backing, 2.14(2), 3.3.2.1, 3.13, 3.13.4, 3.13.6, 4.7.6, 4.7.8, 4.14.2, 5.24.2.3, C-3.3.2.1, C-3.13, C-3.13.4

Backing, removal of, 3.13.5, 3.13.6, 6.10.3.2, 6.10.3.3, C-3.13.5, C-6.10.3.2, C-6.10.3.3

Backing thickness, 3.13.4, C-3.13.4Baking, drying

of flux, 12.6.6.3, C-12.6.6.3of electrodes, 4.5.2, 12.6.7.4, 12.6.7.6,

C-12.6.7.4, C-12.6.7.6Base metal, 1.2, 3.2, 5.4, 5.21.3, 7.2.1,

C-1.2, C-5.21.3, C-7.2.1approval of repair, 12.17.4,

12.17.6(4), C-12.17.4discontinuities, 6.13.4, 12.10.3,

12.10.4, 12.11, C-6.13.4, C-12.10.3

edges, 3.2.3, 3.2.3.1, 12.10, 12.10.3, C-3.2.3, C-3.2.3.1, C-12.10, C-12.10.3

FCAW electrodes for, 12.6.7identification of, 12.4.6, C-12.4.6inspection, 3.2.2.3, 12.9, 12.16.5.1,

C-3.2.2.3, C-12.9, C-12.16.5.1limitations, 1.2.2, C-1.2.2low-sulfur requirements, 12.4.4.1,

C-12.4.4.1optional requirements, 12.4.4,

C-12.4.4oxygen cutting, 3.2.6, C-3.2.6postheat temperature limitations for,

12.15.2.3, 12.17.6(11),(13),C-12.15.2.3

preparation, 3.2, 4.2.8, 5.13, C-5.1.3records, 12.16.5.1, C-12.16.5.1rejection of, 12.12, C-12.12removal, 3.2.2, 3.7, 12.12, 12.13.3,

C-3.2.2, C-3.7, C-12.12,C-12.13.3

repair, 3.2.2, 3.2.3, 3.2.7, 3.3.4.1, 3.7, 12.11, 12.11.3, 12.17, 12.17.2, C-3.2.2, C-3.2.3, C-3.2.7, C-3.3.4.1, C-3.7, C-12.11.3,C-12.17, C-12.17.2

critical, 12.17.3, 12.17.4,C-12.17.3, C-12.17.4

noncritical, 12.17.2.1, 12.17.6,C-12.17.2.1, C-12.17.6

rotation of, 12.11.1, C-12.11.1replacement, 12.11.4, C-12.11.4requirements for FCMs, 12.4, C-12.4SAW electrodes for, 12.6.7SMAW electrodes for, 12.6.2.3,

C-12.6.2.3substitution, 12.11.4, C-12.11.4surfaces, 3.2.1, 3.2.2, C-3.2.1, C-3.2.2testing, 12.15.2.5thicknesses, 3.2.2, C-3.2.2through-thickness requirements,

12.4.4.1, C-12.4.4.1unlisted, 5.4.3.3, 5.4.3.4weldability, 4.2.3, 5.4.3.2, 5.4.3.4,

12.12, C-12.12Beams, 2.17.6

built-up edges, 3.2.7, C-3.2.7camber, 3.5.1.3, C-3.5.1.3

INDEX AASHTO/AWS D1.5M/D1.5:2008

396

depth, 3.5.1.8, C-3.5.1.8splices, 2.17.3straightness, 3.5.1.2, C-3.5.1.2tilt, 3.5.1.7warpage, 3.5.1.7, C-3.5.1.7

Bearing at points of loading, 3.5.1.9, C-3.5.1.9, Fig. C-3.7

bearing stiffeners, 3.5.1.9, 3.5.1.12, C-3.5.1.9, C-3.5.1.12

tolerances, 3.3.2.2, 3.5.1.9, 3.5.1.12, C-3.3.2.2, C-3.5.1.9, C-3.5.1.12

Bend test requirements, 5.20.1welder qualification, 5.26.1, 5.27.3,

12.8.2, C-5.26.1, C-12.8.2welding operator qualification, 12.8.2,

C-12.8.2WPS qualifications, 5.19.2

Bidders, 3.5.1.6(4)Bolt holes, mislocated, restoration by

welding, 3.7.7, C-3.7.7Bolts, 2.16, C-2.16Boxing, 2.3.2.1, 2.8.1.7, Annex D,

C-2.8.1.7Bracing, 3.5.1.4, C-3.5.1.4Break test, fillet welds, 5.26.3.1, 5.26.3.2,

5.27.4, 5.27.5Bursts, 7.2.5, C-7.2.5

CCalibration, UT, 6.17, 6.18, 6.22, Annex

F, C-6.18, C-6.22angle beam, 6.23.2, C-6.23.2angle check, Annex F, A2.2block (IIW), 6.16corner reflector (prohibited), 6.16.2dB accuracy, 6.22.2equipment, 6.15, 6.17, 6.21, C-6.15,

C-6.21horizontal linearity, 6.21.1, Annex

F-A3longitudinal mode, 6.23.1, Annex

F-A1, C-6.23.1nomograph, Annex F: Fig. F.5shear wave mode, 6.23.2, Annex FA2,

C-6.23.2Camber, 3.2.7, 3.2.8, 3.5.1.2, 3.5.1.3,

12.12, 12.15.2, C-3.2.7, C-3.2.8, C-3.5.1.2, C-3.5.1.3, C-12.12, C-12.15.2, Tables 3.2, 3.3, Fig. C-3.5

beams, 3.5.1.3, C-3.5.1.3girders, 3.5.1.3, C-3.5.1.3quenched and tempered steel, 3.2.8,

C-3.2.8

Canadian Welding Bureau, Level I or Level II, 6.1.3.1(2)

Carbon equivalent, 5.4.2, 6.1.1, Annex G, C-5.4.2, C-6.1.1

Caulking, 3.9, C-3.9Certification, 4.8.2, 6.1.3.4

records, 12.16.5, C-12.16.5CVN (test), 5.16.3, 5.18.5, 5.19.5,

Fig. 5.13, Tables 4.1, 4.2CVN (toughness), 12.4.4.2, C-12.4.4.2,

Table 12.1for groove welds, 12.6.4.1, 12.7.2,

C-12.6.4.1, C-12.7.2yield strength, undermatching,

12.6.4.2, C-12.6.4.2Chipping, 3.2.6, 4.14.2, C-3.2.6Cleaning, 3.11, 5.21.5.1, 5.21.5.3, 7.4.1,

C-3.1.1, C-7.4.1weld spatter, 3.11.2, C-3.11.2

Clipping control (UT), 6.18.1, 6.19.6, C-6.19.6

Code interpretations, iii, Annex MCold bending, 12.12, C-12.12Columns, variation from straightness,

3.5.1.1, C-3.5.1.1Combination of welds, 2.15, 2.16Compression members, acceptance,

6.26.2.2splices, 2.17.2, 2.17.3stresses, 6.26.3.1, C-6.26.2.2, Table

6.4Component (FCM), member, 12.2.2,

C-12.2.2Concavity, 3.6.1, 3.7.2.2, 4.11.4, C-3.6.1,

C-3.7.2.2Consumables, welding, 5.5, Table 5.1

diffusible hydrogen limits for, 12.6.2.4, C-12.6.2.4

exemptions, 12.6.1.1, C-12.6.1.1heat or lot testing of, 12.6.1, 12.6.2.1,

C-12.6.1, C-12.6.2.1requirements for FCMs, 12.6

Containers, sealedfor electrodes

for SMAW, 12.6.5.2, C-12.6.5.2for SAW, 12.6.6.3, C-12.6.6.3

production usage, 12.6.5.10,C-12.6.5.10

recovery of flux, 12.6.6.9, C-12.6.6.9Contract documents, 6.7.1.2(d), 12.3,

12.3.3.1, 12.4.4, 12.4.4.1, 12.4.4.2, 12.4.5.1, 12.5.3, 12.6.3, 12.9, 12.10.1, 12.16.1, 12.16.5.1, 12.16.5.2, C-12.3.3.1, C-12.4.4,C-12.4.4.1, C-12.4.4.2, C-12.4.5.1, C-12.9, C-12.10.1, C-12.16.5.1,C-12.16.5.2

acceptance, 12.3.3.2, C-12.3.3.2as fracture critical, 12.1, C-12.1

designation of FCMs, 12.3.2, C-12.3.2postweld thermal treatments, 12.15.1,

C-12.15.1Contractor, 3.4.3, 3.7.2, 4.2.4, 4.5.5,

4.7.5, 4.8.2, 4.12.3, 4.15.1, 5.2.4, 5.7.2, 5.7.3, 5.7.4.1, 5.7.7, 5.13.3, 5.21.6.1, 5.21.7, 5.23.1.3, 5.23.2.4, 5.25.1, 6.6, 7.1.1, 7.2.6, 7.3.3, 7.5.5, 7.6.2, 7.6.4, 7.8.6, 7.8.7, 12.3.3.1, 12.3.3.2, 12.6.6.10, 12.7.4, 12.8, 12.11, 12.11.4, 12.16.1, 12.16.5.2, 12.17.1.1, 12.17.2.1, C-3.4.3, C-3.7.2, C-4.8.3, C-5.2.4, C-5.7.2, C-5.7.3, C-5.7.4.1, C-5.7.7, C-5.13.3, C-5.21.6.1, C-5.21.7, C-6.6, C-7.2.6, C-7.5.5, C-7.6.2, C-7.6.4, C-7.8.6, C-7.8.7, C-12.3.3.1, C-12.3.3.2, C-12.6.6.10, C-12.7.4, C-12.8, C-12.11.4, C-12.16.5.2, C-12.17.1.1, C-12.17.2.1

competence, 12.8.1, C-12.8.1obligations of, 6.6, C-6.6requalification, 12.8.2, C-12.8.2

Convexity, 3.6.1, 3.6.2, 3.7.2.1, 5.27.3, C-3.6.1, C-3.6.2, C-3.7.2.1

Cooling rates, Annex G, Figs. G.2, G.3Cooling times prior to inspection,

12.16.4, C-12.16.4Cope holes, 3.2.4, C-3.2.4, Fig. C-3.2Corner joints, 2.11, 2.12.2, 12.16.2.2,

C-2.11.1, C-12.16.2.2Corner reflector (prohibited), 6.16.2,

C-6.16.2Correction of deficiencies, 6.6.2, C-6.6.2Cracks, 3.7.2.4, 3.7.4, 3.8.1, 5.27.5.1,

6.26.1.1, 6.26.2, Annex J: J2.12, J2.13, C-2.4, C-3.7.2.4, C-3.7.4, C-3.8.1, C-6.26.1.1, C-6.26.1.9, C-6.26.2, C-6.26.3.3

Craters, 3.3.7.1(2), 3.7.2.2, 6.26.1.3, Annex J: J2.12, C-3.3.7.1, C-3.7.2.2, C-6.26.1.3

Current and voltage, maximum, 4.7.3, 5.12.1, 5.12.1.3, 5.12.1.4, C-5.12.1, C-5.12.1.3, C-5.12.1.4

Curving, heat steel, 12.12, C-12.12

DDecibel calculating equation, 6.22.2.1Deficiencies in the work, 6.6.2, C-6.6.2Definitions, 1.5, 2.13.1, 4.9.1, 4.10.1,

Annex DDelamination, Annex J: J2.9Delayed inspection, 6.26.1.9Design of Welded Connections, 2.4,

C-2.4

Beams (Cont’d)

AASHTO/AWS D1.5M/D1.5:2008 INDEX

397

Dew point, 4.13, 4.18Diagrammatic weld, 2.3.2.4, 2.3.4,

C-2.3.4Dimensional tolerances, 2.12.2, 2.13.2,

3.3, 3.5, C-2.12.2, C-2.13.2, C-3.3, C-3.5

Discontinuities, 3.2.3.3, 3.3.7.1(2), 3.6.2, 4.20.6, 5.7.12, 5.18.3.1, 5.26.1.1, 5.27.2, 5.27.3, 6.7.1.2, 6.11, 6.19.6.3, 6.19.8, 6.24.1, 6.24.2, 6.26.2, 6.26.2.1, 7.4.7, 12.9, 12.10.2, 12.11.2, 12.16.5.3, Annex J, C2.4, C-3.2.3.3, C-3.3.7.1, C-3.6.2, C-6.7.1.2, C-6.11, C-6.19.6.3, C-6.19.8, C-6.26.1.6, C-6.26.2, C-6.26.2.3, C-12.9, C-12.10.2, C-12.11.2, Figs. 6.7, 6.8

acceptance criteria, 6.11, 6.26, 12.10.4, 12.17.6, C-6.11, C-12.17.6, Tables 6.3, 6.4

dimensions, 6.26.2.1, 6.26.2.2, Figs. 6.7, 6.8

noncritical, 12.17.2, 12.17.6, C-12.17.2, C-12.17.6

no repair, 3.2.3.7(3), C-3.2.3.7repair, 3.2.3, 3.7, 6.11, 12.17,

12.17.1.1, 12.17.1.2, 12.17.1.3, C-3.2.3, C-3.7, C-6.11, C-12.17, C-12.17.1.1

weld quality requirements, Tables 6.8, 6.9

Disposition of radiographs, 6.12.3, C-6.12.3

Distortion, 3.4.3, 3.7.3, C-2.4, C-3.4.3, C-3.5.1.6(3), C-3.7.3

control, 3.4straightening, 3.7.3, C-3.7.3

Drawings, 2.1, 2.13.3, 2.8.1.7, 3.3.8, 6.5.1, 7.2.1, 7.6.7.1, C-2.1, C-2.13.3, C-6.5.1, C-7.2.1

Dryingarc shields, 7.4.4, C-7.4.4electrodes, 4.5.2, 4.5.3, 4.5.4,

12.6.7.6, C-12.6.7.6flux, 4.8.3, 12.6.6.3, C-12.6.6.3ovens, 4.5.2, 12.6.5.4, 12.6.5.5,

C-12.6.5.4, C-12.6.5.5Ductility requirements, 12.6.3, 12.15.2.5Dyes, low stress, for stamping, 12.4.6,

C-12.4.6

EEccentricity, 2.17.1, C-2.17.1.1,

C-2.17.1.3Edge blocks, 6.10.14, C-6.10.14, Fig. 6.2

Edges, 3.2.6, 3.2.7, 3.2.8, 3.2.9, C-3.2.6, C-3.2.7, C-3.2.8

edge trimming, C-3.2.10Effective throat, see also Effective weld

size, 2.3, 2.3.2, 2.3.2.3, 2.3.2.4, Annex A, Annex B, C-2.3.2.3

diagrammatic weld, 2.3.2.4, 2.3.4, C-2.3.4

Effective weld area, 2.3.1, 2.3.2, 2.3.3, C-2.3.1, C-2.3.3

Effective weld length, 2.3.1.1, 2.3.2.2, 2.3.2.3, C-2.3.2.3

Effective weld size, 2.3.1.3, 2.3.1.5, C-2.3.1.3, Table 2.2

EGW, 1.3.2, 4 Part E, C-1.3.2, Table 5.4, Fig. 5.25

all-weld-metal tension test, 4.16electrodes, 4.17, 5.12.1, C-5.12.1flux, 4.19guide to tubes, 4.17impact strength, Annex Jimpact tests, 4.15.3, Annex Jjoint details, 4.15.1, 5.24.3.2mechanical properties, 4.16procedures, 4.20protection, 4.20.2qualification, 4.15.1quenched and tempered steels, 4.15.2restrictions for FCMs, 12.5.2,

C-12.5.2shielding gas, 4.18WPS, 4.15.1WPS qualification, essential variables,

4.15.1, 5.14.2, C-5.14.2Electrodes, 4.1.1, 4.1.4, 4.5, 4.5.2.3, 4.8,

4.9, 4.10, 4.11, 4.12, 4.14, 4.17, 4.20.3, 5.12.1.1, 5.24.2.1, 5.24.3.2, 5.24.4.1, 7.5.5.2, 12.6, C-5.12.1.1, C-5.24.2.1, C-7.5.5.2, C-Table 5.3, Table 5.3

approved brands, 4.5.6certification, 4.8.2drying, 4.5.2, 12.6.5.4, C-12.6.5.4drying temperature

for FCAW, 12.6.7.6, C-12.6.7.6for SMAW, 12.6.5.4, C-12.6.5.4

EGW, 4.15.2, 4.17, 5.14, C-5.14ESW, 4.15.2, 4.17, 5.14, C-5.14exposure requirements (SMAW),

12.6.5.9, 12.6.5.10, C-12.6.5.9, C-12.6.5.10

FCAW, 4.1.5.4, 4.12.2.2, 4.14, 12.6.7, Tables 4.1, 4.3

flux packaging, 12.6.6.2, C-12.6.6.2for atmospheric corrosion resistance,

4.1.4, 12.6.5.6, C-12.6.5.6, Table 4.3

for tack welding, 12.6.2.2, C-12.6.2.2GMAW, 4.1.5.3, 4.12, 4.14

low hydrogen, 3.2.2.1, 4.1.5.4, 4.5.2, 4.7.8, 7.5.5.2, 7.7.5, C-3.2.2.1, C-7.5.5.2, C-7.7.5, Tables 4.1, 4.7

manufacturer’s certification, 4.5.5, 4.8.2, 7.2.6.2, 7.3.3, Annex E

nonmoisture resistant (SMAW), 12.6.5.7, 12.7.1, C-12.6.5.7, C-12.7.1, Table 4.7

optional R designators, 4.5.2.3, C-4.5.2.3

for tack welding, 12.6.2.2, C-12.6.2.2

for SMAW, 12.6.5.8, 12.7.1, C-12.6.5.8, C-12.7.1

packages for FCAW, 12.6.7.2, C-12.6.7.2

production usage of, 12.6.5.10, C-12.6.5.10

requirementsfor tack welding, Table 12.2optional, for tack welding,

12.6.2.2, C-12.6.2.2optional, for welding, 12.6.2.3,

C-12.6.2.3minimum and maximum,

Tables 12.2, 12.3, 12.4, 12.5SAW, 4.1.5.2, 4.8.1, 12.6.6,

Tables 4.1, 4.3sealed containers for, 12.6.5.2,

C-12.6.5.2SMAW, 4.5.1, 12.6.2.3, 12.6.5.1,

12.6.5.6, 12.6.5.9, C-12.6.2.3, C-12.6.5.1, C-12.6.5.6, C-12.6.5.9, Tables 4.1, 4.3

stickout, 5.12.1.2, 5.12.2.2, C-5.12.1.2, C-5.12.2.2

storage, 4.1.3, 4.5.2, 12.6.5.3, 12.6.7.4, C-12.6.5.3, C-12.6.7.4

storage ovens for, 12.6.5.8, 12.6.7.4, C-12.6.5.8, C-12.6.7.4

time limit extensions for, 12.6.7.5, C-12.6.7.5

usage, 4.1.5, 4.5.2, 4.6, 4.8, 4.9, 4.12End returns, see BoxingEnergy input, Annex GEngineer, 1.1.3, 2.7.1, 3.2.2, 3.2.3.6,

3.2.8, 3.3.4, 3.3.7.3, 3.3.8, 3.4.3, 3.5.1.13, 3.7.4, 3.7.5, 3.7.7.1, 3.7.7.2, 3.8.1, 3.13.3.2, 4.5.6, 4.7.5, 4.8.2.2, 4.10.6, 4.12.4, 4.18, 4.26.2, 5.2.3, 5.2.4, 5.4.3.1, 5.4.3.3(1), 6.1.1.2, 6.6.4, 6.12.2, 6.12.3, 7.2.7, 7.3.1.1, 7.3.3, 7.3.4, 7.8.6, 12.3.1, 12.3.3.1, 12.3.2, 12.3.3.1, 12.3.3.2, 12.4.1, 12.4.4.1, 12.4.4.2, 12.5.2, 12.5.3, 12.6.1, 12.6.6.7, 12.6.7.5, 12.7.5, 12.8,


398

12.8.2, 12.11.2, 12.11.4, 12.12, 12.13.1.1, 12.13.2, 12.15.1, 12.15.2.1, 12.15.2.5, 12.16.1, 12.16.5.2, 12.17.1.1, 12.17.3(2), 12.17.6(5),(11), (12), Annex E, C-1.1.3, C-2.7.1, C-3.2.2, C-3.2.3.6, C-3.2.8, C-3.3.4, C-3.3.7.3, C-3.4.3, C-3.5.1.13, C-3.7.4, C-3.7.5, C-3.7.7.1, C-3.7.7.2, C-3.8.1, C-5.2.3, C-5.2.4, C-5.4.3, C-5.4.3.1, C-6.1.1.2, C-6.6.4, C-6.12.2, C-6.12.3, C-6.26.1.5, C-7.2.7, C-7.3.1.1, C-7.3.4, C-7.8.6, C-12.3.1, C-12.3.2, C-12.3.3.1, C-12.3.3.2, C-12.4.1, C-12.4.4.1, C-12.4.4.2, C-12.5.2, C-12.6.1, C-12.6.6.7, C-12.6.7.5, C-12.8, C-12.8.2, C-12.11.2, C-12.11.4, C-12.12, C-12.13.1.1, C-12.13.2, C-12.15.1, C-12.15.2.1, C-12.16.5.2, C-12.17.1.1, C-12.17.3, C-12.17.6, Table 12.2

EquipmentUT, 6.15, C-6.15welding, 3.1.2, 6.3.2, 7.2.1, 7.5.1,

C-3.1.2, C-6.3.2, C-7.2.1, C-7.5.1

Erection marks, for weld reports, 12.16.5.1, C-12.16.5.1

Essential variables, WPS qualification, 5.13.3, C-5.13.3

EGW, 5.14.2, C-5.14.2, C-Table 5.3, Tables 5.3, 5.4

ESW, C-Table 5.3, Tables 5.3, 5.4FCAW, C-Table 5.3, Tables 5.3, 5.4GMAW, C-Table 5.3, Tables 5.3, 5.4position, 5.8SAW, 5.7.5, 5.14.1, C-5.7.5,

C-5.14.1, C-Table 5.3, Table 5.3

SMAW, C-Table 5.3, Table 5.3tack welder qualification, 5.27.5welder qualification, 5.26.3.1welding operator qualification,

5.26.3.2, 5.28.1ESW, 1.3.2, 4 Part E, C-1.3.2, Table 5.4,

Fig. 5.25electrodes, 4.16, 4.17flux, 4.19guide tubes, 4.17impact strength, Annex Jimpact tests, 4.15.3, Annex Jjoint details, 4.15.1previous qualifications, 4.20.1qualification, 4.15, 5.14.2quenched and tempered steels, 4.15.2

restrictions for FCMs, 12.5.2, C-12.5.2

WPS, 4.20, 5.7.4, 5.7.5, 5.13, C-5.7.4, C-5.7.5, C-5.13

WPS, essential variables, 4.20.1, 5.13.3, C-5.13.3

Extension bars, see Weld tabs

FFabricator, see ContractorFace-bend test, 5.18.3, 5.19.2, 5.26.1,

5.26.2.1, 5.27.3, C-5.26.1, Fig. 5.12

Fatigue, 2.17.6.2Fatigue cracks, Annex J: J2.13Faying surfaces, 3.3.1.1, 3.6.3, 3.13,

C-3.3.1.1, C-3.6.3, C-3.13FCAW, 1.3, 4 Part D, 4.1.5.4, 4.12.2.2,

5.21, 12.6.7, C-1.3, C-Figs. 2.4, 2.5 Note 1, Figs. 2.4, 2.5 Note 1

backing, 4.14.3electrodes, 4.12.1, 4.12.2.2, 4.14.1.1,

4.14.1.5, 12.6.7.1, C-12.6.7.1layer thickness, 4.14.1.5prequalified WPSs, 4.14.1, 4.14.3,

4.14.4progression of passes, 4.14.1.7protection, 4.14.3repair of FCMs, 12.5.1, C-12.5.1shielding gas, 4.13WPS qualification, 5.1.1, C-5.1.1

essential variables, C-Table 5.3, Tables 5.3, 5.4

Field welds, 2.1.1, C-2.1.1Filler metals, 4.1, 4.2, 12.7, C-4.1,

C-12.7, Tables 4.1, 4.2, 5.3electrode-flux, 4.1.1electrodes, 4.1.1, Table 4.1granular, C-Table 5.3, Table 5.3hydrogen control, 4.1.2.1, Annex G,

12.6.2.4, C-12.6.2.4matching requirements, 4.1.4, 4.1.5,

4.1.6, C-4.1.1, C-5.7.11powdered, C-Table 5.3, Table 5.3storage, 4.1.3, 4.5.2welder group designation, 5.21

Filler plates, 2.5, 3.3.1.2, C-3.3.1.2, Figs. 2.1, 2.2

Fillet welds, 5.10, 5.10.2.1, 5.27.6.1, Figs. 5.4, 5.7, 5.8, 5.22, C-2.10.2, C-2.11.2

along an edge, 2.8.1.2, C-2.8.1.2assembly tolerances, 3.3, C-3.3boxing, 2.3.2.1, 2.8.1.7, Annex Dbreak test, 5.26.3, 5.26.3.1, 5.26.3.2,

5.27.4, 5.27.5, C-5.26.3concavity, 3.6.1, C-3.6.1

convexity, 3.6.1, C-3.6.1cooling times for, 12.16.4(1),(2),

C-12.16.4curved, effective length, 2.3.2.2details, 2.8effective length, 2.3.2.1, 2.3.2.2effective throat, 2.3.2.4energy input, Annex G: Table G.2,

Fig. G.4in holes, 2.8.1.3, C-2.8.1.3in lap joints, in slots, 2.8.1.3, 2.8.1.6,

2.9, C-2.8.1.3in lap joints, intermittent, 2.8.1.5,

2.14(4)interrupted, 2.8.1.8, C-2.8.1.8inspection by MT, 6.7.2.3, 12.16.2.3,

C-12.16.2.3macroetch test for, 5.21.5.1, 5.21.5.2,

Fig. 5.8maximum size, 2.8.1.2, 4.1.5, 4.1.5.3,

4.1.5.4, C-2.8.1.2tolerance, 3.1.4, C-3.1.4

minimum size, 2.8.1.1, C-2.8.1.1tolerance, 3.1.4, C-3.1.4

prequalified, 2.8.1, C-2.8.1, Fig. 2.3profiles, 3.6, 5.27.6.1, C-3.6repairs by MT, 12.16.2.3skewed joints, 2.8.1.4, Annex B,

C-2.8.1.4, Fig. 2.3soundness test, Figs. 5.3, 5.8tests, 5.10, 5.18.2, 5.19.3, 5.23.1.4,

5.23.2.4, 5.23.3, 5.26.3, 6.7.2test plates, 5.23.1.4, 5.24.3.1WPS qualification, 12.7.3undersize, 3.1.4, 6.26.1.7, C-3.1.4,

C-6.26.1.7Fine-grain practice, 12.4.2Fissures, Annex J: J2.12Flaw size evaluation, 6.23

angle beam testing, 6.23.2, C-6.23.2straight beam testing, 6.23.1, C-6.23.1

Flux, 4.8, 4.19, 7.2.3, 12.7, C-4.8.3, C-7.2.3, C-12.7

certification, 4.8.2condition, 4.8.3, 4.19damaged packages, 4.8.3, 4.19drying (baking), 4.8.3, 4.19, 12.6.6.3,

12.6.6.4, C-12.6.6.3, C-12.6.6.4

electrode combination, 4.8.1fused, 4.8.4gravity feed delivery systems for,

12.6.6.11, C-12.6.6.11handling of, for SAW, 12.6.6.7,

C-12.6.6.7hoppers, discharge and refill of,

12.6.6.5, C-12.6.6.5open-top systems, for SAW, 12.6.6.6,

C-12.6.6.6

Engineer (Cont’d)


399

packing, 4.8.3, 4.19, 12.6.6.2, C-12.6.6.2

pneumatic delivery systems for, 12.6.6.8, C-12.6.6.8

reclamation, 4.8.4recovery, 12.6.6.9, 12.6.6.10,

C-12.6.6.9, C-12.6.6.10replacement, time limits for, 12.6.6.7,

C-12.6.6.7SAW, 4.8, 12.6.6.2, 12.6.6.3, 12.7.1,

C-12.6.6.2, C-12.6.6.3, C-12.7.1

storage, 4.19, 12.6.6.3, 12.6.6.5, C-12.6.6.3, C-12.6.6.5

Forging, manufacturing requirements, 12.4.4.2, C-12.4.4.2

Forms, Annex LFracture Control Plan (FCP), 12, 12.2.1,

C-12.2.1Fracture Critical Member (FCM), 12,

12.2.2, 12.12, C-12.12individual competence, 12.8.1,

C-12.8.1limits, 12.3.2, C-12.3.2member components, 12.1, C-12.1nonredundant members, 12.1, C-12.1steel bridge members, 12.1, C-12.1

GGain control (attenuator), 6 Part C,

C-6 Part CGamma ray, 6.10.1, C-6.10.1Girders

camber, 3.5.1.3, C-3.5.1.3, Tables 3.2, 3.3

depth, 3.5.1.8, C-3.5.1.8splices, 2.17.6.1, 2.17.6.2stiffeners, 3.5.1.6(2), C-3.5.1.6,

C-3.5.1.6(3)straightness, 3.5.1.2, C-3.5.1.2sweep, 3.5.1.4, C-3.5.1.4testing of, 6.7.2.1, C-6.7.2.1tilt, 3.5.1.7, C-3.5.1.7warpage, 3.5.1.7, C-3.5.1.7web flatness, 3.5.1.6, 3.5.1.6(1), (2),

C-3.5.1.6, C-3.5.1.6(2)GMAW, 1.3.1, 2.8.1, 2.9.1, 2.13.1.1,

4.1.5.3, 4.12.2.1, 4.14, 5.21, C-1.3.1, C-2.8.1, C-2.9.1, C-Figs. 2.4, 2.5 Note 1, Figs. 2.4, 2.5 Note 1

backing, 4.14.2electrodes, 4.12.1, 4.12.2.2, 4.14.1.1,

4.14.1.2, Tables 4.1, 4.2GMAW-S, 2.8.1, 2.9.1, Annex K,

C-2.8.1, C-2.9.1, C-Figs. 2.4,

2.5 Note 1, Figs. 2.4, 2.5 Note 1

layer thickness, 4.14.1.4metal-cored electrodes, 12.5.1,

12.6.5.7, 12.6.7.1, 12.6.7.2, 12.6.7.6, C-12.5.1, C-12.6.5.7, C-12.6.7.1, C-12.6.7.2, C-12.6.7.6, Table 5.2 (Note 1)

prequalified procedures, 4.14.1progression of passes, 4.14.1.7properties of electrodes for, 4.12.2.1protection, 4.14.3restrictions for FCMs, 12.5.2,

C-12.5.2shielding gas, 4.13, 4.14.3, 4.14.4WPS qualification, 5.1.1, 5 Part A,

C-5 Part A, C-5.1.1essential variables, 5, C-Table 5.3,

Tables 5.3, 5.4Gouging, see BackgougingGrinding, 3.2.4, 3.8.1, C-3.2.4, C-3.2.6,

C-3.8.1Groove welds

assembly tolerances, 2.12.2, 3.3, C-2.12.2, C-3.3

backing, 2.12.2, 3.13, C-2.12.2, C-3.3bevel, 5.23.1.2, 5.23.1.3CJP, 6.7.1, C-Fig. 2.4, C-6.7.1, Fig.

2.4cooling times for, 12.16.4(3),(4),

C-12.16.4details, 5.23.1.2, 5.23.1.3, C-Figs. 2.4,

2.5, Figs. 2.4, 2.5, 5.5, 5.6dimensional tolerances, 2.12.2,

2.13.2, 3.3.4, C-2.12.2, C-2.13.2, C-3.3.4

effective length, 2.3.1.1, 2.13.3, C-2.13.3

effective weld size, 2.3.1, 2.13.3, 2.12.3, C-2.3.1, C-2.13.3, Table 2.2

intermittent, 2.14(3)NDT requirements, 12.16.2.2PJP, 2.6, 2.13, 5.9.1, 6.7.2, C-2.6,

C-2.13, C-Fig. 2.5, C-6.7.2, Fig. 2.5

prequalified, 2.12, 2.13, C-2.13, C Figs. 2.4, 2.5, Figs. 2.4, 2.5

profiles, 3.6.2, C-3.6.2, Fig. 3.3size and length, 2.13.3, 3.1.4,

C-2.13.3, C-3.1.4, Table 2.2termination, 3.12, C-3.12test positions, C-5.8.2UT for, 12.16.2.2, C-12.16.2.2yield strength for, 12.6.4.1, C-12.6.4.1WPS qualification, 12.7.2, 12.8.2,

12.10.3, C-12.7.2, C-12.8.2, C-12.10.3

Groove weld test plate, 5.23.1.2, 5.23.1.3, Figs, 5.5, 5.6

Guided bend test jig, 5.26.1, C-5.26.1, Figs. 5.14, 5.15, 5.16

Guide tubes, 4.17

HHardness, 4.10.6, 4.11.6

determinations, 4.10.6.1, 4.11.6.1grinding prior to testing for, 4.10.6.1,

4.11.6.1HAZ

failure in, Annex E: E7.2hardness control, 3.3.7.4, 12.13.3,

Annex G-3, C-3.3.7.4hardness of, 4.10.6, 4.11.6testing of, 4.10.6.1, 4.11.6.1, 5.18.3,

4.4.1Heat input, 4.3, 5.12.1, 5.12.2, 7.4.3,

C-5.12.1, C-5.12.2, C-7.4.3, Tables 12.3, 12.4, 12.5

Heat-shrink method, 3.7.3, 12.12, C-3.7.3, C-12.12

controls, 12.15.2.4testing, 12.15.2.5

Heat testingexemptions from, 12.6.1.1, C-12.6.1.1for diffusible hydrogen, 12.6.2.1,

C-12.6.2.1of weld consumables, 12.6.1, C-12.6.1postheating, 12.15, 12.17.6(11),

C-12.17.6reports, 12.16.5.1, C-12.16.5.1

Heat treatment, 4.4, 4.4.1, 5.7.8, 12.4.4.2, C-5.7.8, C-12.4.4.2

Hermetic containers, 4.5.2Hole-type IQI, 6.10.3.3, 6.10.7,

C-6.10.3.3, C-6.10.7, Table 6.1, Fig. 6.1E

design, 6.10.4, C-6.10.4, Table 6.1essential hole size, Table 6.1location, 6.10.7, C-6.10.7, Fig. 6.1number required, 6.10.7, C-6.10.7RT, using, 12.16.3, C-12.16.3thickness, 6.10.7.2, 6.10.7.3,

C-6.10.7.2, C-6.10.7.3Holes, unacceptable, bolt or punched

appearance, 3.7.7, C-3.7.7approved WPS, 3.7.7(5), C-3.7.7quenched and tempered steels,

3.7.7.3(4), 3.7.7.3restoration by welding, 3.7.7.1,

3.7.7.2, 3.7.7.3, C-3.7.7.1, C-3.7.7.2, C-3.7.7.3

subject to other stresses, 3.7.7(1), C-3.7.7


400

subject to tensile stresses, 3.7.7(2), C-3.7.7

tests required, 3.7.7(1),(3), C-3.7.7Hoppers, flux, 12.6.6.5, 12.6.6.11,

C-12.6.6.5, C-12.6.6.11open top, 12.6.6.6, C-12.6.6.6

Hydrogen control, Annex G: G6.2Hydrogen, diffusible, of weld metal,

12.6.2, C-12.6.2, Table H.1, H.2for FCAW, 12.6.7, 12.6.7.5,

C-12.6.7.5for SAW, 12.6.5for SMAW, 12.6.6.1, 12.6.6.7,

C-12.6.6.1, C-12.6.6.7for tack welding, 12.6.6.2, C-12.6.6.2testing for, 12.6.2.1, C-12.6.2.1welding, for, 12.6.2.3, Annex H,

C-12.6.2.3Hydrogen diffusion, 12.5.1, 12.5.1.1,

12.5.1.2, C-12.5.1

IIIW UT reference block, 6.16.1, 6.21,

C-6.16.1, C-6.21, Fig. 6.5AImpact test, 5.18.5Inadequate joint penetration, 3.6,

Annex B: B2.3, C-3.6Incomplete fusion, 3.7.2.3, Annex J: J2.3,

C-3.7.2.3, Fig. 3.3Inspection

certified reports, 12.16.5, C-12.16.5delay, 6.26.1.9equipment, 6.3general, 6.1, C-6.1, C-6.26.1.9MT, 6.7.6, 6.26.2, C-6.7.6, C-6.26.2NDT, 5.16.2, 5.17, 6.7, 6.26.2, 7.8.1,

C-5.17, C-6.7, C-7.8.1of materials, 6.2, C-6.2PT, 6.7.7, 6.26.4, C-6.7.7QA/QC, 12.17.5, C-12.17.5records, 6.3.1, 6.5, 12.16.5, C-12.16.5RT, 6 Part B, 6.26.2, C-6 Part Bstuds, 7.4.1, 7.4.2, 7.5.5.6, 7.8, 7.8.6,

Annex E: E7.2, C-6.26.2, C-7.4.1, C-7.4.2, C-7.5.5.6, C-7.8, C-7.8.6

UT, 6 Part C, 6.26.2, C-6 Part Cverification, 6.1.1, C-6.1.1visual, 6.26.1, 6.26.1.8, 7.5.5.6,

7.7.1.3, 7.8.1, C-6.26.1.9, C-7.5.5.6, C-7.7.1.3, C-7.8.1

weld, 12.16, 12.16.1.1, C-12.16.1.1welder qualification, 6.4work, 6.5

WPS qualification, 6.3, 12.16Inspector, 6 Part A, 6.1.2, 6.1.3, 6.3.1,

6.6.6, C-6 Part A, C-6.6.6ASNT qualification, 6.1.3.4,

12.16.1.1, 12.16.1.2, C-6.1.3.4, C-12.16.1.1, C-12.16.1.2

AWS Certified Welding, 6.1.3.1Assistant Inspector, 6.1.3.3Canadian Inspectors, 6.1.3.1fabrication/erection, 6.1.1, 6.1.2identification of accepted welds, 6.5.5Lead, 12.16.1.1, 12.16.5.2Quality Assurance, 12.16.5.2,

12.12.1.1technician, 6.1.3.1(3)verification, 6.6.2vision requirements, 6.1.3.7

Intermittent welds, 2.8.1.5, 2.14(3),(4)Interpass temperature, 3.4.7, 4.2, 4.2.1.2,

4.11.6, 5.7.1, 5.7.1.1, 12.6.2, 12.14, 12.15.2.2, 12.17.6(8), Annex H, Tables 4.2, 12.3, 12.4, 12.5, H.1

Interpretation of code provisions, vi, Annex M

IQI, 6.10.1, 6.10.3.3, 6.10.7, Annex D, Table 6.1, Table 6.1A, Fig.6.1F

Isotope radiation, 6.9.1

JJig, wraparound, 5.18.3.3, Figs. 5.14,

5.15, 5.16Joint root openings, 2.9.4Joint WPS, 5 Part A, 5.25.3

limitation of variables, 5.13.3prequalified, 5.11, C-Figs. 2.4, 2.5

Note 1, Figs. 2.4, 2.5 Note 1WPS qualification, 4.15.1, 5 Part A,

C-5 Part AWPS qualification by tests, sample

form, Annex LJoints

corner, 2.11nonstandard, 5.7.7prequalified, 2.8, 2.9, 2.12, 2.13,

C-2.13transition in thickness and width,

2.17.5

LLamellar tearing, 4.2.4, 12.15.1, Annex JLaminations, Annex J: J2.8Lap joints, 2.10, C-2.10.1

Limitation of variables, WPS qualification, 5.13.3

ESW and EGW, 5.14.2, C-Table 5.3, Table 5.3

FCAW, C-Table 5.3, Table 5.3GMAW, C-Table 5.3, Table 5.3SAW, C-Table 5.3, Table 5.3SMAW, C-Table 5.3, Table 5.3

Limitation of variables, tack welders, 5.24.1, 5.24.4

base metals, 5.24.1.1, C-5.24.1.1electrodes, 5.24.1.1, 5.24.3.2,

C-5.24.1.1position, 5.24.2.2, 5.24.3.3welding process, 5.24.1.2, C-5.24.1.2

Limitation of variables, welder, 5.24base metals, 5.24.1.1, C-5.24.1.1electrodes, 5.24.4.1, 5.24.1.3,

C-5.24.1.3progression of welding, 5.24.2.2position, 5.24.2.2qualification, 5.24.1.1, C-5.24.1.1welding process, 5.24.1.2, C-5.24.1.2

Limitation of variables, welding operator, 5.24.1

base metals, 5.24.1.1, C-5.24.1.1electrodes, 5.24.1.3, 5.24.3.2,

C-5.24.1.3position, 5.24.2.2, 5.24.3.3qualification, 5.24.1.1, C-5.24.1.1

Lloyd’s Register of Shipping, 12.6.1.1(2), C-12.6.1.1

Longitudinal cracks, Annex J: J2.12aLot testing

exemptions from, 12.6.1.1, C-12.6.1.1for diffusible hydrogen, 12.6.2.1,

C-12.6.2.1of welding consumables, 12.6.1,

C-12.6.1Low-hydrogen electrodes, 3.2.2.1,

4.1.5.1, 4.5.2, 4.5.2.2, 4.7.8, 7.5.5.2, 7.7.5, C-3.2.2.1, C-7.5.5.2, C-7.7.5, Table 4.5.2

approved, 4.5.2.1atmospheric exposure, Table 4.7condition, 4.5.2redrying, 4.5.4restrictions, 4.5.3storage, 4.5.2

MMachining, 3.2.5, 3.7.1, C-3.2.5, C-3.7.1Macroetch test, 5.18.2, 5.26.3, 5.26.3.2,

5.26.3.4, C-5.26.3, Fig. 5.8Macroetch test specimen, 5.10.3, 5.18.2,

5.26.3.4, C-5.10.3, Figs. 5.21, 5.23

Holes, unacceptable, bolt or punched (Cont’d)


401

Mandatory Annexes, Annex A through Annex G

Manufacturer, 4.5.5, 5.5, 7.2.6.2, 12.6.1, C-12.6.1

electrode certification, 4.5.5, 4.8.2, 4.12.3, 4.16

electrodes for SMAW, 12.6.5.9, C-12.6.5.9

shielding gas certification, 4.13, 4.18stud certification, 7.1, 7.2.6.2, 7.3.3,

C-7.1UT equipment certification, 6.21,

C-6.21Matching filler metal, 4.1.1, 5.15.1Mechanical testing, 5.17, C-5.17Melting-through, 3.13.4, 4.7.6, C-3.13.4Method of testing, 5.18, 5.26, 5.26.3.3Milled joints, C-2.17.3Mill scale, 3.2.1, 3.11.1, 4.19, 7.4.3,

7.5.5.4, C-3.2.1, C-3.11.1, C-7.4.3, C-7.5.5.4

Mill test reports, 12.16.5.1, C-12.16.5.1Mill orders, 12.4.3, 12.4.4, 12.4.5, 12.10,

C-12.4.3, C-12.4.4, C-12.4.5, C-12.10

for CVN requirements, 12.4.5.2, C-12.4.5.2

Mill repairs, 12.4.3, C-12.4.3Misalignment, 3.3.3, C-3.3.3, Fig. C-3.4Mislocated holes, 3.7.7, C-3.7.7MT, 6.7.6, 6.26.2, 12.15.2.3, 12.16.4,

12.17.6(5), C-6.7.2, C-6.7.6, C-12.16.4, C-12.17.6, C-6.26.3.3,C-6.26.5.1

sample form, test report form, Annex L, Form L-1

Yoke method of, 6.7.6.2, 12.10.2, C-6.7.6.2, C-12.10.2

Multiple arc, 4.7.1, 4.11Multiple electrodes, 4.11Multiple pass, 3.3.7.2, 5.10.3(1),

C-3.3.7.2, C-5.10.3

NNDT, 2.26.3.2, 5.16.2, 5.17, 6.6.5, 6.7, 6

Parts B and C, 6.26, Annex F, Annex H: H3, C-5.17, C-6.6.5, C-6.7, C-6 Parts B and C

MT, 6.7.6, 6.26.2, 12.17.6(5), C-6.7.6, C-12.17.6

personnel qualification, 6.1.3, 6.1.3.4PT, 6.7.7, 6.26.4, C-6.7.7RT, 6 Part B, C-6 Part BSNT-TC-1A, 6.1.3.4, C-6.1.3.4timing, 6.26.5unlisted base metals, 5.4.3UT, 6 Part C, C-6 Part C

NDT Technicians, 12.16.1, 12.16.1.2weld types, 12.16.2weld repair, 12.17.6(1), C-12.17.6

NDT, weld requirements (FCP), 12.16.2butt welds, repaired, 12.16.2.1,

C-12.16.2.1noncritical, 12.17.2(2), C-12.17.2

corner joints, 12.16.2.2, C-12.16.2.2fillet weld repairs, 12.16.2.3,

C-12.16.2.3groove welds, repaired, 12.16.2.2,

12.17.2(4), C-12.16.2.2, C-12.17.2

inspection reports, 12.16.5, C-12.16.5tension, butt joints, 12.16.2.1,

C-12.16.2.1T-joints, 12.16.2.2, C-12.16.2.2

Nomograph, UT attenuation, Annex F, Fig. F.10, Form F-4

Noncontinuous beams, 2.17.6.3Nonredundant members, 12, C-12

OOffset, 3.3.3, 3.5.1.7, C-3.3.3, C-3.5.1.7,

Fig. C-3.3Optional code provisions or

requirements, 1.1.3, 3.1.5, 6.1.1, 6.1.3, 6.7, C-1.1.3, C-3.1.5, C-6.1.1, C-6.7

Ovens, storage (drying) see Storage ovens

Overlap, 3.6.5, 3.7.2.1, Annex J: J2.7, C-3.6.5, C-3.7.2.1

Owner, 1.1.3, 3.5.1.13, 6.6.5, 6.20.2, C-1.1.3, C-3.5.1.13, C-6.6.5, C-6.20.2

Oxygen cutting, 3.2.6, C-3.2.6plate preparation, 3.2

PPaint, removal of, 3.2.1, 6.19.3, C-3.2.1,

C-6.19.3Parallel electrodes, 4.7.1, 4.10Peening, 3.8, 12.17.6(10), C-3.8,

C-12.17.6slag removal, 3.8.2, C-3.8.2unacceptable peening, 3.8.1, C-3.8.1use of vibrating tools, 3.8.2, C-3.8.2

Penetrameters, see IQIPersonnel qualification for NDT, 6.1.3.4,

C-6.1.3.4Piping porosity, 6.13.3, 6.26.1.6,

Annex J: B2.1d, C-6.13.3, C-6.26.1.6, C-6.26.1.8

Plug welds, 2.3.3, 2.9, 2.17.2, 3.3.1.1, 4.21, 5.2.1.4, 5.27.6.2, C-2.3.3, C-3.3.1.1

depth of filling, 2.9.7, C-2.9.7effective area, 2.3.3macroetch test, 5.26.3.4, Fig. 5.23qualification tests, 5.23.1.5, Fig. 5.23size, 2.9.2, C-2.9.2spacing, 2.9.3technique for making, 4.21

Porosity, 3.7.2.3, 6.13.3, 6.26.1.6, 6.26.2.1, Annex J: J2.1, C-3.7.2.3, C-6.13.3, C-6.26.1.6

Position of welding, 5.8, 5.22, 5.22.1, 5.24.3.3, 5.28.2, 7.6.1, 7.6.3.2, C-5.28.2, C-7.6.1, C-7.6.3.2

Postheating, see Postweld thermal treatments

Postweld thermal treatments (PWHT), 12.15, 12.15.1, 12.17.6(11),(13), C-12.15.1, C-12.17.6

approval of, 12.15.2.1controls, 12.15.2.1, C-12.15.2.1definition of, 12.15.2, C-12.15.2limitations, 12.15.2.3, C-12.15.2.3minimum temperatures, 12.15.2.2,

C-12.15.2.2testing, 12.15.2.5

Preheat, 3.3.7.1(1), 4.2, 4.2.1.1, 4.10.6, 4.11.6, 7.5.5.5, 12.14, 12.15.2.2, 12.17.6(8), C-3.3.7.1, C-7.5.5.5, C-12.14, C-12.15.2.2, C-12.17.6, Tables 4.4, 12.2, Annex G: Table G.2, Annex H: Tables H.1, H.2

effect on hardness, 4.10.6, 4.11.6Prequalified joint details, 2.8.1, 2.9.1,

C-2.8.1, C-2.9.1, C-Figs. 2.4, 2.5, Figs. 2.4, 2.5

Prequalified WPS, 5.11, C-5.11weld metal limitations, 5.15, C-5.15

Pressure vessels or piping, 1.1.1(2), C-1.1.1

Pretest definition, 5.7.2, C-5.7.2Procedure specification, see WPSProcesses not in code, 1.3.5, C-1.3.5Prod method of MT, 6.7.6.1Production weld thickness, 5.6, C-5.6Profiles, weld, 3.6, 6.26.1.4, C-3.6Progression of welding, 4.6.8, 4.14.1.7,

5.24.2.2Prohibited welded joints, 2.14Protective coatings, 3.2.1, 3.11.2, 7.4.1,

7.4.2, C-3.2.1, C-3.11.2, C-7.4.1, C-7.4.2

PT, 6.7.7, 8.26.2.4, C-6.7.7, C6.26.4, C6.26.5.1

Punched holes, repair, 3.7.7, 12.17.3(6), C-3.7.7, C-12.17.3


402

QQualification, 5

combined WPSs, 5.7.9exempt procedures, 5.7.6forms, Annex Lgeneral requirements, 5 Part A, 5.7,

12.16, C-5 Part A, C-5.7.10nonconforming WPS, 5.11, NDT,

6.7.7prequalified WPS, 5.11, 5.11.1,

C-5.11previously qualified WPS, 5.7.2,

C-5.7.2records, 5.16, 5.32, 5.43, 5.51required tests, 5.12.1, 5.12.2, 5.15,

C-5.12.1, C-5.12.2, C-5.15retests, 5.20, 5.28, 5.28.1, 5.28.2,

C-5.28stud application, 7.6tack welders, 5 Part BUT unit, Annex Fverification testing, 5.7.3welders, 5 Part B, 5.3, 5.23.1.1welding operators, 5 Part B, 7.7.4WPS, 5 Part A, 5.9, 5.21.3, C-5 Part

A, C-Fig. 5.1, C-Fig 5.2, Figs. 5.1, 5.2

QA/QC (Quality Assurance/Quality Control), 12.16.1, 12.16.5.2, 12.17.5, 12.17.6, C-12.16.5.2, C-12.17.5, C-12.17.6

Quality of welds, 6.26, 7.7, 12.16, C-7.7

RRadiographic Inspection, see RTRadiographs, 5.21.5.3, 5.26.1.2, 6.10.1,

6.10.5, 6.10.7, 6.26.2, C-6.10.1, C-6.10.5, C-6.10.7, C-6.26.2, Figs. 6.10.5A through D

Contractor’s obligation, 6.12, C-6.12density limitations, 6.10.11, C-6.10.11density measurements, 6.10.11.1,

6.10.11.2, C-6.10.11.1, C-6.10.11.2

identification of, 6.10.12, C-6.10.12quality, 6.10.10, C-6.10.10submitted to Owner, 6.12.3, C-6.12.3supplement to UT, 6.13.3, C-6.13.3

Records, 5.2.4, 5.21.7, 5.28.2, 6.5, 12.16.5, C-5.2.4, C-5.21.7, C-5.28.2, C-12.16.5

Reduced-section tension tests, 5.15.1(1), 5.16.3

test specimen, Fig. 5.10Re-entrant corners, 3.2.4, C-3.2.4,

Fig. C-3.1

Reference block, UT IIW, 6.16.1, C-6.16.1, Fig. 6.5A

other approved designs, 6.16.1, Annex F, C-6.16.1, Fig. 6.5B

Reference documents, Annex NReinforcement, 3.6.2, 3.6.3, 6.10.3,

C-3.6.2, C-3.6.3, C-6.10.3removal of, 3.6.3, C-3.6.3

Reject control (UT), 6.18.1, 6.19.6, C-6.19.6

Repair, 3.2.2, 3.2.7, 3.3.4, 3.7.2, 3.7.7, 12.16, 12.16.5.1, C-3.2.2, C-3.2.7, C-3.3.4, C-3.7.2, C-3.7.7, C-12.16.5.1, Table 3.1

of cracks, 3.7.2.4, C-3.7.2.4of fillet welds, 12.16.2.3, C-12.16.2.3of plate, 3.2.3, C-3.2.3of studs, 7.7.3, 7.7.5, C-7.7.3, C-7.7.5welding, definition of, 12.17, C-12.17

critical, 12.17, 12.17.3, C-12.17, C-12.17.3

noncritical, 12.17, 12.17.2, 12.17.2.1, C-12.17, C-12.17.2, C-12.17.2.1

Report forms, Annex FReports, 6.12, 6.20, C-6.12Responsibility of Contractor, 5.2,

5.21.6.1, 6.6, 12.8, C-5.2, C-5.21.6.1, C-6.6, C-12.8

Restoration by welding, of holes, 3.7.7, C-3.7.7

Restraint, Annex G: G6.2.5Retests, 5.20, 5.28, 5.28.1, 5.28.2,

C-5.28, C-5.28.2Rivets, 2.16, C-2.16Root-bend test, 5.16.3, 5.25.2, 5.26.2.1,

5.27.3, Figs. 5.12, 5.13, 5.22Root face, 3.3.4, C-3.3.4Root opening, 2.9.4, 3.3.1, 3.3.4, 3.3.4.1,

C-3.3.1, C-3.3.4, C-3.3.4.1build-up of, 3.3.4.1, C-3.3.4.1

RT, 5.15, 5.16.2, 5.17, 5.21, 5.25.1, 5.26.1, 5.26.1.2, 5.26.1.3, 5.27.2, 6 Part B, 6.7.1.1, 6.7.1.2, 6.26.2, 12.8.2, 12.16.2.1, 12.16.5.1, C-5.15, C-5.17, C-5.26.1, C-6.7.1.1, C-6.7.1.2, C-6 Part B. C-12.8.2, C-12.16.2.1, C-12.16.5.1

acceptance, 5.12.5, 5.26.1.2, 6.11, 6.26.2, C-6.11

backscattered radiation, 6.10.8.2, C-6.10.8.2

extent of testing, 6.7, 6.8, C-6.7, C-6.8film type, 6.10.4, C-6.10.4film width, 6.10.9, C-6.10.9gamma ray sources, 6.10.6, C-6.10.6general, 6.10.1, 6.10.8, 12.16.4,

C-6.10.1, C-6.10.8, C-12.16.4

image quality indicators, 6.10.1, 6.10.7, 6.10.7.5, C-6.10.1, C-6.10.7, C-6.10.7.5, Tables 6.1, 6.1A, Figs. 6.1A through Fig. 6.1F

hole-type IQI, 6.10.7, C-6.10.7, Table 6.1, Fig. 6.1E

radiograph illuminator, 6.12.1, C-6.12.1

requirements, 12.16.3, C-12.16.3safety, 6.10.2, C-6.10.2source location, 6.10.5, C-6.10.5sources, 6.10.6, C-6.10.6surface preparation, 6.10.3, C-6.10.3wire IQI, 6.10.7, 6.10.7.4, 6.10.7.5,

C-6.10.7, C-6.10.7.4, C-6.10.7.5,Table 6.1A, Fig. 6.1A through D

X-ray unit size, 6.10.6, C-6.10.6RT procedure, 6.10Run-off plates, see Weld tabsRust-inhibitive coating, 3.2.1, C-3.2.1

SSafety, 1.7, 6.10.2, C-6.10.2Sample report forms, Annex LSAW

diffusible hydrogen for, 12.6.6.1, C-12.6.6.1

drying (baking), 12.6.6.3, C-12.6.6.3electrode diameter, 4.7.3electrodes and fluxes, 4.7.1, 4.8,

12.6.2.2, 12.6.2.3, 12.6.6, C-12.6.2.2, C-12.6.2.3

flux handling, 12.6.6.3, C-12.6.6.3flux reclamation, 4.8.4general requirements, 4.7hardness testing, 4.10.6, 4.10.6.2,

4.11.6, 4.11.6.2heat input, 4.7.2interpass temperature, 4.10.6,

4.10.6.2, 4.11.6.2layer thickness, 4.10.3, 4.11.3macroetch test specimens, 4.7.5,

4.10.6.1(1), 4.11.6.1(1)maximum current, 4.7.3, 4.10.4.1,

4.11.4.1multiple arcs, 4.7.1multiple electrodes, 4.7.1, 4.11

definition, 4.11.1hardness determination, 4.11.6.1

parallel electrodes, 4.7.1, 4.10, 5.19.3.2

definition, 4.10.1hardness determination, 4.10.6.1position, 4.10.2


403

reduction of preheat and interpass temperatures, 4.10.6

restriction on fillet welds, 4.10.6.2tack weld requirements for,

Table 12.2weld layer thickness, 4.10.3welding current limitations,

4.10.4.1, 4.10.5with GMAW root pass, 4.10.5

position, 4.11.2preheat, 4.10.6, 4.11.6prequalified WPS, 4.9, 4.10, 4.11reduction of preheat and interpass

temperatures, 4.11.6repair of FCMs, 12.5.1, C-12.5.1restriction on fillet welds, 4.11.6.2

weld current limitations, 4.11.4.1weld layer thickness, 4.11.3with GMAW root pass, 4.11.5

sample joint, 4.10.6.1, 4.11.6.1single electrodes, 4.9, 4.11.4.1,

5.19.3.2definition, 4.9.1tack welds, 4.7.8

WPS qualification, 3.13.6, 5 Part A, C-5 Part A

essential variables, C-Table 5.3, Tables 5.3, 5.4

Sequence, 3.4.3, C-3.4.3Shear connectors, 7.2.5, 12.10, C-7.2.5,

C-12.10, Fig. 7.1Shielding gas, 4.13, 4.14.3, 4.14.4, 4.18

dew point, 4.13, 4.18EGW, 4.18FCAW, 4.13, 12.6.7.3, C-12.6.7.3GMAW, 4.13manufacturer, 4.13, 4.18wind protection, 4.14.3

Shop drawings, 2.1, 12.3.3, 12.3.3.1, 12.3.3.2, 12.11.2, 12.11.4, 12.16.5.1, C-2.1, C-12.3.3, C-12.3.3.1, C-12.3.3.2, C-12.11.2, C-12.11.4, C-12.16.5.1

for weld repair, 12.17.1.2Shop splices, 3.4.6, C-3.4.6Shop welds, 2.1.1, C-2.1.1Short circuiting transfer, 1.3.4, 2.13.1.1,

4.14.4, Annex K, C-Figs. 2.4, 2.5 Note 1, Figs. 2.4, 2.5 Note 1

Shrinkage, 3.4due to cutting, 3.2.7, C-3.2.7due to welding, 3.2.7, C-3.2.7

Side-bend test, 5.15.1, 5.16.3, 5.25.2, 5.26.2, 5.26.2.1, 5.27.3, Fig. 5.11

Size effects, 2.3Slag, 3.11.1, C-3.11.1Slag inclusion, 3.7.2.3, C-3.7.2.3Slag removal, required, 3.11.2, C-3.11.2

use of slag hammers, 3.8.2, C-3.8.2

use of vibrating tools, 3.8.2Slot welds, 2.3.3, 4.22, C-2.3.3

cleaning, 3.11.1effective area, 2.3.3, C-2.3.3ends, 2.9.5length, 2.9.4operator qualification, 5.23.2.3prequalified condition, 2.9.1.1,

C-2.9.1.1size, 2.9.6spacing, 2.9.6technique for making, 4.22thickness, 2.9.2, C-2.9.2welder qualification, 5.23.1.1

SMAW, 1.3.1, 2.8.1, 2.9.1, 4.1.5.1, 4.5, 4.6, 5.24.4.1, 7.5.5, 12.6.5, C-1.3.1, C-2.8.1, C-2.9.1, C-7.5.5

electrodes, 4.1.1, 4.5.1, 12.6.5.1, 12.6.5.9, C-12.6.5.9

atmospheric exposure, 4.5.2.1, 12.6.5.6, 12.6.5.8, C-12.6.5.6, C-12.6.5.8

containers for, 12.6.5.3, C-12.6.5.3non-moisture-resistant electrodes

for, 12.6.5.7, C-12.6.5.7optional moisture-resistant

designator electrodes for, 12.6.5.8

layer thickness, 4.6.5, 4.6.7maximum fillet weld size, 4.6.6

of studs, 7.5.5, C-7.5.5prequalified procedures, 4.6root pass, 4.6.5stud welding, 7.5.5, C-7.5.5WPS qualification, 5 Part A,

C-5 Part Aessential variables, C-Table 5.3,

Tables 5.3, 5.4repair of FCMs, 12.5.1, C-12.5.1storage of, 12.6.5.3, C-12.6.5.3

SNT-TC-lA qualification, 6.1.3.4, C-6.1.3.4

Spatter, 3.11.2, C-3.11.2Splices, 2.17.2, 2.17.3, C-2.17.2

splice planes, C-2.17.6.2Steels

approved, 12.4.1cambering, 12.12, C-12.12cold bending, 12.12, C-12.12heat curving, 12.12, C-12.12other than M270M [M270] (A 709M

[A 709]) Grades 100/100W [690/690W], 3.2.2.1, C-3.2.2.1

straightening, 12.12, C-12.12Steels, quenched and tempered, 3.2.6,

3.7.3, 4.3, C-3.7.3, C-6.26.5.2camber correction, 3.2.7, C-3.2.7heat input control, 4.3

WPS qualification, 5.1.1, 5.13.2, C-5.1.1, C-5.13.2

Stiffeners, 12.10, C-12.10bearing, 3.5.1.9, 3.5.1.12, C-3.5.1.9,

C-3.5.1.12fit, 3.5.1.10intermediate, 2.17.6.2, 3.5.1.10,

C-3.5.1.10straightness, 3.5.1.11, C-3.5.1.11

Storage ovensfor electrodes

for FCAW, 12.6.7.4, C-12.6.7.4for SAW, 12.6.6.3, 12.6.6.4,

C-12.6.6.3, C-12.6.6.4for SMAW, 12.6.5.3, 12.6.5.4,

12.6.5.5, 12.6.5.9, C-12.6.5.3, C-12.6.5.4, C-12.6.5.5, C-12.6.5.9

drying temperatures for, 12.6.5.4, C-12.6.5.4

Straightening, 3.4.8, 3.7.3, 12.12, 12.15.2, C-3.4.8, C-3.7.3, C-12.12, C-12.15.2

Straightness, 3.5.1.1, C-3.5.1.1Stress relief, 4.4, 4.4.1

alternate temperatures, 4.4.3cooling, 4.4.2.2heating, 4.4.2.2quenched and tempered steels, 4.4.2.3temperature, 4.4.2

Structural detailsbeams, 2.17.6built-up members, 2.17.4eccentricity, 2.17.1fillet welds, 2.10girders, 2.17.6lap joints, 2.10noncontinuous beams, 2.17.6.3T- and corner joints, 2.11transition of thickness, 2.17.5transition of width, 2.17.5

Studsacceptance, Annex Eapplication qualification, 7.1, 7.6base qualification, 7.2.4, 7.2.6, 7.3,

7.4, 7.5, 7.6, 7.6.5, 7.6.6.1, 7.7, 7.8, Annex E: E7.2, E8, E9, C-7.2.4, C-7.2.6, C-7.3, C-7.4, C-7.6.5, C-7.7, C-7.8

certification, 7.2.6.2, 7.3.3.1, 7.3.3.2, C-7.3.3.1, C-7.3.3.2

cracks, 7.2.5, C-7.2.5decking, 7.6.1.2description, 7.3.1, 7.4.7, C-7.3.1design, 7.2.1, C-7.2.1finish, 7.2.5, C-7.2.5length of studs, 7.2.1, C-7.2.1, Fig. 7.1manufacturers, 7.1, 7.2.6.2, 7.6.2,

Annex E, C-7.1, C-7.6.2


404

materials, 7.3.1, C-7.3.1mechanical requirements, 7.1, 7.3,

C-7.1, C-7.3, Fig. 7.2moisture, 7.4.1, 7.4.3, C-7.4.1,

C-7.4.3not prequalified, 7.6.1.2oil, 7.4.1, 7.4.4, C-7.4.1, C-7.4.4operator qualification, 7.7.4removal, 7.7.5, C-7.7.5rust, 7.4.1, 7.4.3, C-7.4.1, C-7.4.3scale, 7.4.1, 7.4.3, C-7.4.1, C-7.4.3shear connectors, 7.4.5, 7.8.5, C-7.4.5,

C-7.8.5tensile requirements, 7.3.1.1, Annex

E: E7.1, C-7.3.1.1, Fig. 7.2torque testing, 7.6.6.2, 7.8.3,

C-7.6.6.2, C-7.8.3, Fig. 7.3type A, Table 7.1, 7.8.5type B, Table 7.1, 7.4 5, 7.8.5

Stud weldingapplication qualification

requirements, 7.6arc shields, 7.2.2, 7.4.4, 7.4.6,

Annex F: F3, C-7.2.2, C-7.4.4, C-7.4.6

automatically timed welding equipment, 7.2.1, 7.5.1, 7.5.2, C-7.2.1, C-7.5.1, C-7.5.2

certification, 7.2.6.2decking, 7.4.3, C-7.4.3fabrication inspection, 7.7.3, 7.8,

C-7.7.3, C-7.8ferrule, 7.7.2, 7.4.4, 7.4.6, C-7.7.2,

C-7.4.4, C-7.4.6fillet welded studs, 7.5.5, C-7.5.5

electrode diameters, 7.5.5.2, C-7.5.5.2

inspection, 7.5.5.6, 7.8, C-7.5.5.6, C-7.8

low hydrogen electrodes, 7.5.5.2, C-7.5.5.2

minimum size, 7.5.5.1, C-7.5.5.1, Table 7.2

preheat requirements, 7.5.5.5, C-7.5.5.5, Table 4.4

flash, 7.4.7, 7.7.1.3, 7.7.3, 7.8.1, C-7.7.1.3, C-7.7.3, C-7.8.1

flux, 7.2.3, C-7.2.3general requirements, 7.2, 7.5.5.6,

7.7.1.3, 7.7.1.4, 7.7.1.5, 7.8, C-7.2, C-7.7.1.3, C-7.7.1.4, C-7.7.1.5, C-7.8

inspection, 7.5.5.6, 7.7.1.3, 7.7.1.4, 7.7.1.5, 7.8, C-7.5.5.6, C-7.7.1.3, C-7.7.1.4, C-7.7.1.5, C-7.8

length of studs, 7.2.1, C-7.2.1, Fig. 7.1

moisture, 7.4.1, 7.4.3, 7.4.4, C-7.4.1, C-7.4.3, C-7.4.4

operator qualification, 7.7.4pre-production testing, 7.7.1production control, 7.7, C-7.7production welding, 7.7.2, C.7.7.2repair, 7.7.3, C-7.7.3removal, 7.7.5, C-7.7.5rust, 7.4.1, 7.4.3. C-7.4.1, C-7.4.3scale, 7.4.1, 7.4.3, C-7.4.1, C-7.4.3

SMAW, 7.5.5, C-7.5.5stud base qualification, 7.2.4, 7.2.6,

C-7.2.4, C-7.2.6, Annex E: E3, E4

technique, 7.5torque tests, 7.6.6.2, 7.8.1, C-7.6.6.2,

C-7.8.1, Fig.7.3workmanship, 7.4, C-7.4

Surface preparation, 3.2.1, 3.11, C-3.2.1, C-3.11

Surface roughness, 3.2.1, 3.6.3, 3.6.4, 12.13.3, C-3.2.1, C-3.6.3, C-3.6.4, C-12.13.3

Surface roughness guide, 3.2.2, C-3.2.2Symmetry, C-2.17.1.3

TTack welder qualification, 5 Part B

eligibility, 5.22.4fillet weld break test, 5.27.5,

Figs. 5.14, 5.26, 5.27, 5.28limitation of variables, 5.24method of testing specimens, 5.26.3.3,

Figs. 5.28, 5.29period of effectiveness, 5.21.4,

C-5.21.4records, 5.21.7, C-5.21.7

test report form, Annex Lretests, 5.28.2, C-5.28.2requirements, 12.13.1.2, C-12.13.1.2,

Table 12.2test results, 5.27test specimens, 5.25.3, Figs. 5.28,

5.29tests, 5.26.3.3

Tack welders, 5 Part B, 5.24.1, 6.4, 12.8.2, Figs. 5.28, 5.29

qualification variables, 5.24.4Tack welds, 3.3.7, C-3.3.7

designator requirements for, 12.6.2.2, C-12.6.2.2

discontinuities, 3.3.7.1(2), C-3.3.7.1in final weld, 3.3.7.2, C-3.3.7.2location, 12.13.1.1, C-12.13.1.1minimum temperatures, 4.2.1multiple pass, 3.3.7.2, C-3.3.7.2preheat, 3.3.7.1, C-3.3.7.1

interpass temperatures, Tables 12.3, 12.4, 12.5

quality, 3.3.7.1, C-3.3.7.1removal, 3.3.7.3, 3.3.7.4, 12.13.3,

C-3.3.7.3, C-3.3.7.4, C-12.13.3size, 4.7.8temporary, 12.13.2, C-12.13.2

Technical inquiries, iii, Annex MTemporary welds, 3.3.8, C-3.3.8Temperature variation, 4.4.2Tensile strength, 12.4.4.1, 12.10,

C-12.4.4.1, C-12.10FCM not subject to, 12.2.2, C-12.2.2weld removal, 12.13.3, C-12.13.3

Tensioncomponents, 12.2.2, C-12.2.2and repaired butt welds, 12.16.2.1,

C-12.16.2.1noncritical repair of butt welds,

12.17.2(2), C-12.17.2zone, 12.2.2.1, C-12.2.2.1

Tension members, 2.17.2, 12.2.2, C-2.17.2

acceptance, Annex Irepair, 3.2.3, C-3.2.3retest, 5.20.1splices, 2.17.2stress, 6.26.2.1, 6.26.3.1, C-6.26.2.1,

Table 6.3Tension specimens, Figs. 5.9, 5.10Tension test, stud weld, 7.6.6.3, C-7.6.6.3Tension test fixture studs, Fig. 7.2Terms, 7.6.2, C-7.6.2Testing agency, 7.6.2, C-7.6.2, Annex E:

E2Testing frequency, 5.3, 12.7.4, C-5.3,

C-12.7.4Test plates, welded

heat treatment, 5.7.8, C-5.7.8tack welder qualification, Fig. 5.28thermal cutting, 3.2.2, 12.10, C-3.2.2,

C-12.10welder qualification, Figs. 5.17

through 5.23welding operator qualification, 7.7.4,

12.8.2, C-12.8.2, Figs. 5.17 through 5.23

WPS qualification, C-Fig. 5.1, C Fig. 5.2, Figs. 5.1, 5.2, 5.3, 5.8

Test results, 5.19, 5.27, 5.28.1, 12.6.1, C-12.6.1

Test specimens, 5.16, 5.25, 5.26, C Fig. 5.1, C-Fig. 5.2, Table 5.5, Figs. 5.1, 5.2, 5.6, 5.7, 5.8, and Figs. 5.14 through 5.28

Tests in excess of code, 5.2.4, C-5.2.4Tests, welding variables, 4.24Test weld positions, 5.21

Studs (Cont’d)


405

Thermal cutting, 12.10, 12.11.2, C-3.2.2, C-12.10, C-12.11.2

edge requirements (TCES), 12.10.1, C-12.10.1

Throat cracks, Annex J: J2.12dThrough-thickness direction, 12.4.4.1,

C-12.4.4.1T-joints, 2.11, 12.16.2.2, C-2.11.1,

C-12.16.2.2Toe cracks, Annex J: J2.12eTolerances

alignment, 3.3.3, 3.5.1.8, 3.5.1.11, C-3.3.3, C-3.5.1.8, C-3.5.1.11

bearing joints, 3.3.2.2, C-3.3.2.2camber, 3.5.1.3, C-3.5.1.3, Tables 3.2,

3.3dimensional, 2.12.2, 2.13.2, 3.3.4, 3.5,

C-2.12.2, C-2.13.2, C-3.3.4, C-3.5

flatness, 3.5.1.5offset, 3.5.1.5, C-3.5.1.5variation from straightness, 3.5.1.1,

C-3.5.1.1warpage, 3.5.1.7, C-3.5.1.7

Torque testing, 7.6.6.2, 7.8.3, C-7.8.3, Fig. 7.3

Toughness, see Weld metal toughnessof base metal, 12.4.5, Table 12.1supplementary requirements, 12.4.5.1,

C-12.4.5.1Transducer calibration, 6.21, C-6.21Transducer specifications, 6.15.6, 6.15.7Transitions of thickness or widths, 2.17.5,

C-2.17.5, Figs. 2.7, 2.8Transverse cracks, Annex J: J2.12a

UUnderbead cracking, Annex J: J2.12gUndercut, 3.3.7.1, 3.7.2.2, 4.9.4, 5.19.3.1,

5.19.6, 5.27.1, 5.27.4.1, 5.27.5.1, 5.27.6.1, 6.26.1.5, Annex J: J2.5, C-3.3.7.1, C-3.7.2.2, C-6.26.1.5, Fig. 3.3

Undercut, repair of weld, 12.17.2, C-12.17.2

Underfill, Annex J: J2.6Undermatching filler metal, 2.1.6, 4.1.1,

5.4.6, 5.5.3, 5.15.1, 12.6.4.2, C-2.1.6, C-5.15.1, C-12.6.4.2

Unlisted base metal, 5.4.3.4UT, 6 Part C, 12.16.2.1, 12.16.2.2,

12.16.4, C-6 Part C, C-12.16.2.1, C-12.16.2.2, C-12.16.4, C-6.26.3.1, C-6.26.3.2, C-6.26.5.1

acceptance criteria, 6.26.3, Tables 6.3, 6.4, C-Tables 6.3, 6.4

amplitude, Annex F: FA1.2

attenuation factor, 6.19.5.4base metal discontinuities, 6.13.4,

12.15.2.5, C-6.13.4calibration, 6.16, 6.17, 6.18, 6.21,

C-6.18, C-6.21calibration for angle beams, 6.18.5,

Annex F: FA2.2distance, 6.18.5.1, C-6.18.5.1horizontal sweep, 6.18.5.1,

C-6.18.5.1zero reference level sensitivity,

6.18.5.2calibration for longitudinal mode,

6.21.1, Annex F: FA2.2calibration for shear mode, 6.21.2,

Annex F: FA2amplitude calibration, 6.21.2.4,

Annex F: FA1.2distance calibration, 6.21.2.3,

Annex F: FA2.3resolution, 6.21.2.5sound entry point 6.21.2.1sound path angle, 6.21.2.2transducer positions, Fig. 6.6

crossing patterns, 6.19.6.2, C-6.19.6.2

calibration for straight beam, 6.18.4horizontal sweep, 6.18.2, 6.18.4.1,

6.18.5.1, C-6.18.4.1, C-6.18.5.1

sensitivity, 6.18.4.2calibration for testing, 6.18, C-6.18

distance, 6.18.5.1, C-6.18.5.1horizontal sweep, 6.18.5.1,

C-6.18.5.1zero reference level sensitivity,

6.18.5.2equipment, 6.15, C-6.15

gain control, 6.15.4horizontal linearity, 6.15.2, 6.22.1search units

angle beam, 6.15.7straight beam, 6.15.6

equipment qualification, 6.17calibration block, 6.17.4, C-6.17.4certification, 6.17.3, C-6.17.3dB accuracy, 6.22.2gain control, 6.17.2, C-6.17.2horizontal linearity, 6.17.1,

Annex F: FA3, C-6.17.1internal reflections, 6.22.3

examples, 6.25, C-6.25extent of testing, 6.14flaw length determination, 6.19.7,

C-6.19.7flaw size evaluation procedures, 6.23,

6.25.2angle beam testing, 6.23.2,

C-6.23.2

straight beam testing, 6.23.1, C-6.23.1

indication length, 6.19.7, C-6.19.7indication rating, 6.19.6.3, 6.19.6.5,

C-6.19.6.3, C-6.19.6.5laminar reflector, 6.19.5.1, C-6.19.5.1longitudinal mode calibration, 6.21.1nomograph, Annex F: Fig. F.10operator requirements, 6.14.2,

C-6.14.2personnel qualification, 6.7, C-6.7procedures, equipment qualification,

6.22, Annex F, C-6.22horizontal linearity, 6.22.1, Annex

F: FA.3internal reflectors, 6.22.3vertical linearity, 6.22.2.1

procedures, flaw size evaluation, 6.23angle beam testing, 6.23.2,

C-6.23.2straight beam testing, 6.23.1,

C-6.23.1reference blocks IIW, 6.16, 6.16.1,

C-6.16.1, Figs. 6.5A, 6.5Bother approved blocks, 6.16.1,

C-6.16.1, Fig. 6.5Brepairs, 6.19.10report forms, Annex F, Annex L

information on, 6.19.6.3, 6.19.6.4, 6.19.6.5, 6.20.1, C-6.19.6.3, C-6.19.6.4, C-6.19.6.5, C-6.20.1

reports, 6.19.6.4, 6.19.6.5, 6.19.9, 6.20, 12.16.5.3, C-6.19.6.4, C-6.19.6.5, C-6.19.9

disposition, 6.20.3, C-6.20.3examples forms, 6.25, C-6.25examples of, 6.25.1, 6.25.2

reporting repairs, 6.19.9, 6.19.9.1, C-6.19.9, C-6.19.9.1

requirements, 6.7.1.2, C-6.7.1.2RT supplement, 6.13.3, C-6.13.3scanning patterns, 6.24, C-6.24,

C-6.26.3.3, Fig. 6.7ESW and EGW welds, 6.24.3longitudinal discontinuities, 6.24.1transverse discontinuities, 6.24.2

search unitsamplitude, 6.21.2.4angle beam, 6.15.7, 6.19.6, 6.23.2,

C-6.23.2dimensions, 6.15.6, 6.15.7.6distance calibration, 6.21.2.3resolution, 6.21.2.5sensitivity, 6.21.2.4shear wave mode, 6.21.2sound entry point, 6.21.2.1sound path angle, 6.22.2.2straight beam, 6.16.6, 6.19.5,

6.23.1, C-6.19.5, C-6.23.1


406

testing procedure, 6.19, Table 6.2cleanliness of surfaces, 6.19.3,

C-6.19.3couplant materials, 6.19.4,

C-6.19.4flaw length, 6.19.7, C-6.19.7

testing repair welds, 6.19.9.1, C-6.19.9.1

thickness limitations, 6.13.1, C-6.13.1transducer size, 6.15.6, 6.15.7.2,

C-6.15.7.2weld identification, 6.19.1, 6.19.2,

C-6.19.1

VVerification inspection, 6.1.1, C-6.1.1Verification test

definition, 5.7.3, C-5.7.3procedure test, C-Fig. 5.1, C-Fig. 5.2,

Figs. 5.1, 5.2Vertical position welding

prequalified, 4.6.8, 4.14.1.7restrictions on, 4.6.8, 4.14.1.7, 5.8.2.3,

5.24.2.2, C-5.8.2.3Visual inspection, 3.2.3, 5.19.6, 5.27.1,

6.5.5, 6.6.2, 6.26.1, 7.5.5.6, 7.7.1.3, 7.7.1.5, 7.8.1, 12.16.4, 12.16.5.1, C-3.2.3, C-6.5.5, C-6.6.2, C-7.5.5.6, C-7.7.1.3, C-7.7.1.5, C-7.8.1, C-12.16.4, C-12.16.5.1, C-6.26.1, C-6.26.1.6, C-6.26.1.9

Voltage, maximum, 4.7.3, 5.12.1.4, 5.12.3.2, 5.12.3.4, C-5.12.1.4, C-5.12.3.2, C-5.12.3.4

WWarpage, 3.4, 3.5.1.7, C-3.5.1.7,

Fig. C-3.6Web flatness, 3.5.1.6, Annex C,

C-6.26.3.3Web-to-flange welds, 6.26.3.3Weldability investigation, 5.4.3.1,

C-5.4.3.1Weld cleaning, 3.11, 5.7.12, 5.21.5,

C-3.11completed welds, 3.11.2, C-3.11.2in-process cleaning, 3.11.1, C-3.11.1use of manual hammers, 3.8.2,

C-3.8.2use of lightweight vibrating tools,

3.8.2, C-3.8.2Welded joint details, see Joints

prohibited, C-2.14Welder qualification, 5 Part B, 5.24.2

fillet weld tests, 5.23.1.4, 5.27.4, Figs. 5.4, 5.7, 5.8, 5.21, 5.22

groove weld tests, 5.23, 5.23.1.2, 5.23.1.3

limitation of variables, 5.24.2limited thickness, 5.23.1.3method of testing, 5.26period of effectiveness, 5.21.4plug welding tests, 5.23.1.5, 5.26.3.4,

Fig. 5.23position, 5.8.1, 5.22.1, C-5.8.1preparation, 5.23.1.5records, 5.21.7, C-5.21.7retest, 5.28.1semiautomatic, 5.24.3.4test plates

fillet welds, Figs. 5.4, 5.7, 5.21, 5.26

groove welds, Figs. 5.5, 5.6, 5.17 through 5.20

macroetch, Figs. 5.8, 5.23, 5.26test results, 5.19. 5.27

bend tests, 5.27.3fillet weld break tests, 5.26.3.1,

Figs. 5.21, 5.26, 5.27, 5.28macroetch test, 5.26.3.4, Figs. 5.8,

5.23, 5.26RT, 5.26.1.2

visual, 5.27.3, 5.27.6test specimens, 5.25

Welders, 3.1.2, 5 Part B, 5.24.1, 6.4, 12.8.2, C-3.1.2, 5, C-12.8.2

Weldingat low temperatures, 3.1.3, 4.2, 7.5.4,

C-3.1.3, C-7.5.4designator requirements for, 12.6.2.3,

C-12.6.2.3equipment, 3.1.2, 4.26.1, 6.3, C-3.1.2processes, 12.5progression, 3.4.2, 4.6.8, 4.14.1.7,

C-3.4.2restrictions, 12.5.2, 12.5.3, C-12.5.2sequence, 3.4.2, C-3.4.2test plate thickness, 5.6, C-5.6,

Figs. 5.17 through 5.20, 5.24Welding consumables, 5.5, Table 5.1Welding operators, 5 Part B, 5.24.1.3,

5.21.4, 6.4, 7.7.4, 12.8.2Welding operator qualification, 5 Part B,

5.23.2, 7.7.4, Figs. 5.17 through 5.21

ESW/EGW weld tests, 5.23.3.1, 5.23.2.2

fillet weld tests, 5.4.2, 5.23.2.4, 5.27.4, C-5.4.2, Figs. 5.7, 5.8, 5.22

groove weld tests, 5.23.2.1, Figs. 5.5, 5.6

limitations of variables, 5.24, Fig. 5.6method of testing, 5.26period of effectiveness, 5.21.4,

C-5.21.4plate weld tests, Figs. 5.17, 5.18preparation of test specimens, 5.25retests, 5.28.1stud welds, 7.7.4test report form, Annex Ltest results required, 5.27

bend tests, 5.27.3fillet weld break tests, 5.26.3.2,

Fig. 5.21macroetch tests, 5.26.3.4,

Figs. 5.21, 5.23RT, 5.26.1.3visual, 5.27.1

test specimens, 5.26, Table 5.5Welding sequences, 3.4.2, C-3.4.2Welding symbols, 1.6Weld inspection, 6, 12.16

inspectors, 12.16.1.1, C-12.16.1.1NDT technicians, 12.16.1.2,

C-12.16.1.2QA/QC, 12.16.1, 12.16.1.1,

C-12.16.1.1Weld metal removal, 3.7.6, 12.13.3,

C-3.7.6, C-12.13.3Weld metal strength, 12.6.3, 12.11.4,

C-12.11.4heat treatment, 12.15.2.5requirements of, Tables 4.1, 4.2toughness of, Table 12.1

Weld metal toughnessfor groove welds, 12.6.4.1, C-12.6.4.1requirements, 12.6.4testing, 12.15.2.5

Weld profiles, 3.6.1, 3.6.2, 3.6.3, C-3.6.1, C-3.6.2, C-3.6.3, C-6.26.1.4, Fig. 3.6

Weld spatter, removal of, 3.11.2, C-3.11.2

Weld tabs, 3.12.1, 3.12.3, 6.10.3.1, C-3.12.1, C-3.12.2, C-3.12.3, C-6.10.3.1

Wind velocity, 3.1.3, 4.14.3, 4.20.2, C-3.1.3

Workmanship, 3, 3.7.1, 7.4alignment, 3.3, C-3.3control of distortion and shrinkage,

3.4, 3.7.3, C-3.7.3general requirements, 3inspection, 6.4.2, 6.5.4, 6.5.5, 7.8.6,

C-6.4.2, C-6.5.4, C-6.5.5, C-7.8.6

repairs, 3.7, C-3.7tolerances, 3.5, C-3.5

UT (Cont’d)


407

visual inspection, 3.2.3, 6.5.5, 6.26.1, 7.5.5.6, C-3.2.3, C-6.5.5

weld profiles, 3.6, 6.26.1.4, C-3.6WPS, 5 Part A, 5.21.2, 12.3.3.1, 12.17.1,

C-5 Part A, C-Table 5.3, C-Fig. 5.1, C-Fig. 5.2, Tables 5.3, 5.4, Figs. 5.1, 5.2

Contractor requirements for, 12.8qualification for

fillet welds, 12.7.3groove welds, 12.7.2limitation of variables, 5.5.2, 5.13

pretest, C-Fig. 5.1, C-Fig. 5.2, Figs. 5.1, 5.2

previous, 12.7.5records, 5.2.4results required, 5.19retests, 5.20SMAW, 127.1tests, 5.12, 5.12.1.1, 5.13.3, 5.15test weld positions, 5.8

period of effectiveness, 12.7.4requalification, 12.8.2sample forms, Annex L

YYield strength, 12.17.6, Tables 4.1,

4.2for cooling times of welds, 12.16.4for FCAW, 12.6.7.1for groove welds, 12.6.4.1for SAW, 12.6.6.1for SMAW, 12.6.5.8undermatching, 12.6.4.2

Yoke method, of MT, 6.7.6.2,12.10.2



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AASHTO/AWS D1.5M/D1.5:2008 LIST OF AWS DOCUMENTS

409

List of AWS Documents on Structural Welding

Designation Title

D1.1/D1.1M Structural Welding Code—Steel

D1.2/D1.2M Structural Welding Code—Aluminum

D1.3/D1.3M Structural Welding Code—Sheet Steel

D1.4/D1.4M Structural Welding Code—Reinforcing Steel

D1.5M/D1.5 Bridge Welding Code

D1.6/D1.6M Structural Welding Code—Stainless Steel

D1.8/D1.8M Structural Welding Code—Seismic supplement

D1.9/D1.9M Structural Welding Code—Titanium



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