ms-17 welding procedur - preparation

PT. DUTA GRAHA INDAH Tbk

Method Statement

Project Karebbe HEP- Package K-8A Road and Oil Pipeline Realignment

MS 16 ITEM: WELDING

PROCEDURE

(PREPARATION)

Location Soroako – Sulawesi Selatan Revision 00 Prepared by TS

Pages 2 of 5 Date 16-Jul-09 Approve to issue SKW

1.0 PURPOSE

The purpose of this procedure is to provide guidelines for qualifying WPS required in the

pipeline welding work.

2.0 SCOPE

This procedure shall be applied for welding procedure qualification test on all WPS

established in the pipeline welding work and related works.

3.0 REFERENCE

ASME B31.4-2002 : Pipeline Transportation System for Liquid Hydrocarbon and Other Liquid

API 1104-2005 : Welding of Pipeline and related Facilities.

4.0 DEFINITION /ABBREVIATION

WPS - Welding Procedure Specification.

WPQT - Welding Procedure Qualification Test.

PQR - Procedure Qualification Record.

WQT - Welder Qualification Test.

5.0 PROCEDURES

5.1 WPS preparation

5.1.1 DGI Welding Engineer and Sucofindo Crew would identify and submit to KHP

the list of relevant WPS to be used for the project from the pre-accepted WPS.

If additional WPS is required, WPS shall be developed and submitted for KHP

approval before WPQT.

5.1.2 The Welding Engineer and Sucofindo Crew would formulate the welding

procedures to the joint configuration and application. The WPS would reference

to ASME B31.4-2002, Pipeline ASME B31.4 paragraph 434.8.3 for WPS for Cross

Country Pipeline would be performed in accordance with API 1104.

5.1.3 The proposed WPS would contain all Specification Information (API 1104-2005

paragraph 5.3.2) including the essential welding parameters (API 1104-2005

paragraph 5.4)

5.1.4 Upon approval of the WPS, a WPQT would be carried out in the presence of

KHP. KHP shall be informed as soon as possible in advance prior to the testing.

5.2 Step in Conducting WPQT

5.2.1 Prior to commencement of WPQT, the following shall be verified by KHP, DGI

welding engineer, Sucofindo Crew.

a) Test materials used, including the pipe number, heat number.

b) Dimensions of the test materials e.g. length, diameter, thickness etc.

c) Edge preparation of the test materials.

d) Adequacy of lighting for cleaning and visual inspection.


Method Statement


MS 16 ITEM: WELDING

PROCEDURE

(PREPARATION)



e) Current i.e. amperage and voltage by mean of AC/DC Digital Clamp Meter.

f) Setting of current type, polarity including amperage and voltage.

g) Correctness of welding consumables to be used as per proposed WPS.

5.2.2 Upon fit-up, weld preparation and alignment shall be checked for compliance to

the proposed WPS. After fit-up inspection, mark the PQR number, test position

and indicate the top of joint position.

5.2.3 The test piece shall be secured firmly per the required test position.

5.2.4 A trial test may be carried out on a separate specimen prior to welding on the

test piece to ensure the welding parameters set out in the WPS are maintained.

5.2.5 Monitor and record the following welding parameters in the PQR form on each

pass until completion of test weld to ensure compliance within the ranges

specified in the proposed WPS.

a) Travel speed, wire feed speed current i.e. Amperage and voltage by mean of

AC/DC Digital Clamp meter.

b) Type of Shielding Gas, Purging Gas & flow rate.

c) Direction of travel for vertical welding

d) Use of specified welding consumables diameter, electrode stick out length.

e) Welding technique i.e. string, weave, split layer.

f) Interpass temperature by use of Thermosticks or digital thermometer.

g) Approximate width of weld pass.

h) Approximate thickness of welds layer.

i) Interpass cleaning method.

j) Sequence and number of weld passes per layer.

5.2.6 Welding would be check with visual inspection and NDT RT (Refer to ASME

13.4-2002 paragraph 434.8.5(a)(1))

5.2.7 DGI Welding Engineer would procees the locations of test specimens on the

welded test piece for each type of destructive test before cutting at site or

direct dispatch to aft approved independent testing laboratory for both cutting

and machining work. The location for removal of the required specimen shall be

in accordance with API 1104-2005 paragraph 5.6.

5.2.8 The entire required test carried out in the laboratory would be witnessed by the

Sucofindo, DGI Representative and Client’s Representative.

5.2.9 Accordance to API 1104 table 2, type and number of test speciments for PQT

are

a) For tensile strength are 2 spicements

b) For nick-break test are 2 spicements

c) For root bend test are 2 spicements

d) Fof face bend test are 2 speciments


Method Statement


MS 16 ITEM: WELDING

PROCEDURE

(PREPARATION)



5.2.10 The following would be checked during the course of mechanical testing:

a) Identification markings on the specimen (refer to API 1104 Fig-3) to its

related PQR number, type of test and number of specimens required.

b) Dimensions of Tensile-Strength Test, Nick-Breake Test, Root-and Face-Bend

Test, specimens (Refers to API 1104 Fig-4, Fig-5, Fig-6, Fig-7)

c) Calibration certificates of Tensile Test and Nick-Break Test equipment are

valid.

d) Dimensions of guided bend test equipment must be adequate to produce

bending radius specified by test code for root (Refer to API 1104 Fig-9).

e) Imperfections dimension after Nick-Break Test in exposed weld surface

shown in API 1104 Fig-8.

5.2.11 During each test all results would be recorded on the draft copies of test report

by the laboratory tester.

5.2.12 Upon completion, test results shall be signed off and a copy extended to the

DGI, Sucofindo and KHP representative for signature and evaluation against the

test code and specification.

5.2.13 Upon acceptance of the mechanical test results, the WPS/PQR would be

prepared by the DGI welding engineer using the format shown in appendix I.

The WPS/PQR would be submitted to CLIENT for review and approval.

5.3 Retest

5.3.1 When Retest is not allowed unacceptable defects evaluated by visual, NDT and

Mechanical testing shall be cause for rejection. A new test weld shall be

required.

5.3.2 When retest is allowed when one of the following mechanical test specimens

fails to meet the required acceptance criteria, two additional specimens shall be

prepared for retesting. The location of the two additional specimens shall

reflect the location of the failed specimen. If one or both of the retest

specimens fail, then this shall be cause for rejection. A new weld would be

required

Prior to retest, a study and evaluation shall be made on the failed test to

established probable cause of failure.

6.0 SPECIAL REQUIREMENTS

6. 1 DGI welding engineer and Sucofindo shall be prepared the WPS to simulate, the actual

welding conditions and materials to be used for production welding. Limitations

imposed by the essential variables of the procedure qualification shall be adhered to in

production welding.

6. 2 Only skilled and experienced welder(s) shall be assigned for WPQT to minimize rework.


Method Statement


MS 16 ITEM: WELDING

PROCEDURE

(PREPARATION)



7.0 RECORDS

All records pertaining to welding qualification test shall be kept by the DGI Welding Engineer.

All copies of the approved WPS shall be readily available for reference by the Welders,

Welding Engineers and KHP.

ms-17 welding procedur - preparation

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