welding lab...1 =length of test piece. • t can be of different thickness. welding conditions (6.3)...

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TC2 Technical Consultancy Srl

White Papers : Qualification testing of welders – Fusion welding

WELDING LAB

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TABLE OF CONTENTS

Standards for qualification testing of welders Normative references (2) Terms and definitions (3) Welding processes (4.2) Essential parameters (5.1) Welding processes (5.2) Product type (5.3) Type of weld (5.4) Filler material grouping (5.5) Dimension (5.7) Welding position (5.8) Weld details (5.9) Examination (6.1) Test pieces (6.2)

Welding conditions (6.3) Test methods (6.4) Acceptance requirements for test pieces (7)

Period of validity (9) Revocation of qualification (9)

Welder's qualification test certificate (10)

Designation (11)

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Purpose: Ensure the ability of a welder to follow written instructions and verify the welders skill. These are

important factors in ensuring the qualify of a welded product.

Principle: The welder is qualified for the same and all other conditions which are considered easier to weld.

Standards for qualification testing of welders

• EN ISO 9606-1 – Steels (substitutes SS-EN 287-1) • EN ISO 9606-2 – Aluminium and aluminium alloys • EN ISO 9606-3 – Copper and copper alloys • EN ISO 9606-4 – Nickel and nickel alloys • EN ISO 9606-5 – Titanium and titanium alloys, zirconium and zirkonium alloys

Normative references (2)

The standard refers to severel standards that are indispensable for the application of this

standard.

For dated references, only the edition cited applies. For undated references, the latest edition of the

referenced document (including any amendments) applies.

Terms and definitions (3)

The standard refers to several terms and definitions which are specified in the

beginning of the standard. It is important to read these definitions.

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Welding processes (4.2)

• 111 manual metal arc welding • 114 self-shielded tubular cored arc welding • 121 submerged arc welding with solid wire electrode (partly mechanized) • 125 submerged arc welding with tubular cored electrode (partly mechanized) • 131 MIG welding with solid wire electrode • 135 MAG welding with solid wire electrode • 136 MAG welding with flux cored electrode • 138 MAG welding with metal cored electrode


• 141 TIG welding with solid filler material (wire/rod) • 142 autogenous TIG welding • 143 TIG welding with tubular cored filler material (wire/rod) • 145 TIG welding using reducing gas and solid filler material (wire/rod) • 15 plasma arc welding • 311 oxyacetylene welding

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Essential parameters (5.1)

• welding process(es) and transfer mode • product type (plate or pipe) • type of weld (butt or fillet) • filler material group • filler material type • dimension (material thickness and outside pipe diameter) • welding position • weld detail(s) (material backing, gas backing, flux backing, consumable insert, single side welding, both

side welding, single layer, multi-layer, leftward welding, rightward welding).


Normally each welding process only qualifies the actual welding process. A change of welding

process requires a new qualification test. However there are some exceptions: • 135 qualifies 138 or vice versa. • 121 qualifies 125 or vice versa. • 141, 143 or 145 qualifies for 141, 142, 143 and 145, but 142 only qualfies for 142. • Dip (short-circuit) transfer mode (131, 135 and 138) qualifies other transfer modes, but not vice

versa. And it is also possible to qualify two or more welding process by welding a single test piece (multi-process joint).

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Product type (5.3)

• Test pieces with outside diameter > 25 mm covers welds in plate. • Test pieces in plate cover pipes ≥ 500 mm in accordance with table 9 (weld position, butt weld) and

10 (weld position, fillet weld) • Test pieces in plate cover rotating pipes ≥ 75 mm in welding position PA, PB, PC and PD. As long as the

weld position has been qualified according to table 9 and 10.

Type of weld (5.4)

• Test pieces welded as butt weld (BW) qualifies any type of butt welds (BW) except for branch joints

with an angle ≤ 60º. • Butt welds (BW) do not qualify fillet welds (FW) or vice versa. • To qualify a BW and a FW in the same certificate a supplementary fillet weld (FW) test can be welded.

The test piece shall be at least 10 mm thick or the thickness of the butt weld. Welded as a single layer

in PB position. This qualifes the range of qualification for FW based upon the BW essential parameters.

Type of weld (5.4)

• It is also possible to qualifie a fillet weld in combination with a butt weld according to figure C.1.

Min. 10 mm

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Filler material grouping (5.5)

The filler material shall be from one of the groups listed in table 2. The parent material should be suitable for the filler metal and from ISO/TR 15608 groups 1 to 11.

Filler material grouping (5.5)

FM1: Non-alloy and fine grain steels FM4: Creep-resisting steels 3,75 ≤ Cr ≤ 12 % FM2: High-strength

steels

FM5: Stainless and heat-resisting steels FM3: Creep-resisting steels Cr < 3,75% FM6: Nickel and nickel

alloys

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Filler material type (5.5)

Welding with filler material qualifies welding without filler material, but not vice

versa.

For 142 and 311 (without filler metal) the parent material group used during the test

is what the welder is qualified for.

Group Subgroup Type of steel

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Steels with a specified minimum yield strength ReH ≤ 460 N/mm2, C ≤ 0,25, Si ≤ 0,60, Mn ≤ 1,8, Mo ≤ 0,70, S ≤ 0,045, P ≤ 0,045, Cu ≤ 0,40, Ni ≤ 0,5, Cr ≤ 0,3, Nb ≤ 0,06, V ≤ 0,1, Ti ≤ 0,05

1.1 Steels with ReH ≤ 275 N/mm2

1.2 Steels with 275 N/mm2 < ReH ≤ 360 N/mm2

1.3 Normalized fine-grain steels with ReH > 360 N/mm2

1.4 Steels with improved atmospheric corrosion resistance


The range of filler material types are given in Table 4 and 5

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The range of filler material types are given in Table 4 and 5

Dimension (5.7)

For BW the dimension is based on outside pipe diameter (table 7) and deposited thickness (table 6).

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Dimension (5.7)

Dimension (5.7)

For FW the dimension is based on material thickness (table 8).

Welding position (5.8)

The test pieces shall be welded in accordance with ISO 6947. PA: flat position PB: horizontal vertical position

PC: horizontal position

PD: horizontal overhead position

PE: overhead position

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Welding position (5.8) The test pieces shall be welded in accordance with ISO 6947.


Welding postions for butt welds in plate. PA PE PF PC PG

Welding position (5.8) Welding postions for butt welds in pipe.

PA (pipe rotating) PH (pipe fixed) PJ (pipe fixed)

PC H-L045 (pipe fixed) J-L045 (pipe fixed)

PF: vertical up position

PG: vertical down position PG

PH PJ

PF

PH: pipe position for welding upwards

PJ: pipe position for welding downwards

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Welding position (5.8) Welding postions for fillet welds in plate.

PD PF PG

Welding position (5.8) Welding postions for fillet welds in pipe. PA (pipe rotating) PB PB (pipe rotated) PD PH (pipe fixed) PJ (pipe fixed)

PA PB

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Welding position (5.8) The range of qualfication for each welding position is given in Tables 9 and


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• Welding two positions in PH and PC position with

the same diameter covers the same range as

a pipe welded in H-L045. • Welding two positions in PJ and PC position with

the same diameter covers the same range as a

pipe welded in J-L045. • If a pipe has a diameter ≥ 150 mm it can be welded

in two welding positions. PH or PJ 2/3 of

circumference and PC 1/3 of circumference.

Weld details (5.9) The range of qualification for weld details are specified in Table 11 and 12.

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Weld details (5.9)

Weld details (5.9) For welding process 311, a change from rightward welding (rw) to leftward welding (lw) and vice versa

requires a new qualification test.

Rightward welding (rw) Leftward welding (lw)

Examination (6.1)

The welding and testing shall be witnessed by the examiner or examining body. Examiner/Examining body can be: • Representative of the company • Accredited third party • Notified body

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Examination (6.1) The test piece shall be marked with: VS 7582 Weld pos. PC

• Examiner ID

• Welder ID

• Welding position

• For pipes also the 12 o’clock position

Test pieces (6.2)

Dimension of test piece for a butt weld in plate. • t=material thickness of test piece. • Dimensions in mm.

Test pieces (6.2) Dimension of test piece for a fillet weld on plate. • t=material thickness of test piece. • t can be of different thickness. • Throat thickness is specified by pWPS or WPS. • Dimensions in mm.

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Test pieces (6.2)

Dimension of test piece for a butt weld in pipe. • Less than 150 mm in circumfenses requires additional

test pieces, but maximum three test pieces. • t=material thickness of test piece. • D=outside pipe diameter. • Dimensions in mm.

Test pieces (6.2)

Dimension of test piece for a fillet weld on pipe • t=material thickness of test piece. • D=outside pipe diameter.

• l1=length of test piece.

• t can be of different thickness.

Welding conditions (6.3)

• The welder shall follow a pWPS or WPS according to ISO 15609-1 or ISO 15609-2. • Test piece shall have at least one stop and restart in the root and capping run. For a multiprocess this is

a requirement for both weld method. • Stop and restart shall be marked. • For root and filler runs minor imperfections are allowed to be removed after permission from

the examiner. • In capping run only stop and restart may be grinded. • Any post-weld heat treatment requried in the pWPS or WPS may be omitted. • The examiner can cancel the qualification at any time (Eg. the welder doesn’t follow pWPS/WPS, lack of

skills of the welder, major repairs)

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Test methods (6.4)

For welding process 111,114, 121, 125, 136, 141, 142, 143, 145, 15 the following test methods apply.

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• Either Radiographic testing or bend or fracture tests shall be used.

• Radiographic testing can be replaced be ultrasonic testing in ferritic steels t ≥ 8 mm.

• Bend or fracture test can be replaced by tensile test if D ≤ 25 mm.

Test methods (6.4)

For welding process 131, 135, 138 and 311 the following test methods apply

• Either Radiographic testing or bend or fracture tests shall be used.

• When radiographic testing is used, then additional bend or fracture tests are mandatory.

• Radigraphic testing can be replaced be ultrasonic testing in ferritic steels t ≥ 8 mm.

• Bend or fracture test can be replaced be tensile test if D ≤ 25 mm.

Butt weld Visual Testing

ISO 17637

Radiographic Testing

ISO 17636

Bend Test

ISO 5173

Fracture Test

ISO 9017

Butt weld Visual Testing

ISO 17637

Radiographic Testing

ISO 17636

Bend Test

ISO 5173

Fracture Test

ISO 9017

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Test methods (6.4)

For welding process 111, 114, 121, 125, 131, 135, 136, 138, 141, 142, 143, 145, 15 and 311 the following test methods apply.

• Fracture test can be replaced by a macroscopic examination of at least two sections. At least one

section shall be taken from the stop/start location.

• The fracture test on pipes may be replaced by radiographic testing.

Acceptance requirements for test pieces (7)

The finished test pieces shall be examined to determine whether it meets the requirements.

Except for 25 mm on each end of the test piece (plate).

The test piece shall be evaluated according to ISO 5817, quality level B.

Except for: • excess weld metal (502), • excessive convexity (503), • excessive throat thickness (5214), • excessive penetration (504), • undercut (501) Where level C shall apply. The visual testing shall be according to ISO 17637.

Fillet Weld &

Branch Joint

Visual Testing

ISO 17637

Fracture Test

ISO 9017

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Acceptance requirements for test pieces (7)

Prior to any testing, the following shall be checked: • All slag and spatters are removed. • No grinding on the root and the face side of the weld (according to 6.3). • Stop and restart in the root run and in the capping run are identified. • Profile and dimensions.

Period of validity (9)

The welder’s qualification begins from the date of welding and is valid with the following method: a) The welder qualfication shall be retested every 3 years. b) The welder qualfication shall be revalidated after 2 years. c) The welder qualficiation is valid as long as the following fulfills:

– The welder is working for the same manufacturer. – The manufacturer has a verified quality requirement according to ISO 3434-2 or ISO 3834-3. – The manufacturer has documented that the welder has produced welds of acceptable quality where weld position, weld type, material backing or no material backing conforms to the examination.

The chosen method shall be stated on the certificate.

Period of validity (9)

Regardless of the chosen method the welder certificate has to be confirmed every 6 months by the responsible person for welding. This conformation shows that the welder has worked within the range of qualification of the certificate. It this confirmation hasn’t been done the welder certificate is invalid.

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Revocation of qualification (9)

When there is a specific reason to question a welder's ability to make welds that meet the product standard quality requirements, the qualifications shall be revoked. All other qualifications not questioned remain valid.


If the welder pass the qualification test a welder certificate shall be issued. All essential variables shall be recorded: • welding process(es) and transfer mode • product type (plate or pipe) • type of weld (butt or fillet) • filler material group • filler material type • dimension (material thickness and outside pipe diameter) • welding position • weld detail(s)


And also the following non-essential variables: • type of current and polarity • parent material group/subgroup • shielding gas The examination of job knowledge (see Annex B) shall be designated by “Accepted” or “Not tested”. The supplementary fillet weld test shall be recorded on the certificate for the associated butt weld qualification.

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Designation (11)

The designation of a welder qualification shall compromise the following items in the order given:

9606-1 111 P FW FM1 B t10,0 PB ml

1 2 3 4

5 6 7 8 9

1. The part of the standard ISO 9606-1. 6. Filler material types. 2. Welding process. 7. Dimension of test piece (s,t or D) 3. Product type (Plate (P) or Pipe (T)). 8. Welding position 4. Type of weld, BW or FW. 9. Weld details 5. Filler material group or parent material group.

welding lab...1 =length of test piece. • t can be of different thickness. welding conditions (6.3)...

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