specification 580 rev. 0 - pipelines welding and ndt testing

GDF SUEZ E&P Nederland B.V.Specification 580, Rev. 0 Page 2 of 54

TABLE OF CONTENTS

1. INTRODUCTION .........................................................................................................................................51.1 General ............................................................................................................................................51.2 Scope ..............................................................................................................................................51.3 Quality Assurance.............................................................................................................................51.4 Quality Plan ......................................................................................................................................51.5 Inspection Notice .............................................................................................................................51.6 Terms and Definitions ......................................................................................................................61.7 Abbreviations ...................................................................................................................................6

2. REFERENCED CODES, STANDARDS AND SPECIFICATIONS .........................................................................72.1 Codes and Standards .......................................................................................................................7

3. GENERAL ..................................................................................................................................................93.1 Scope ..............................................................................................................................................93.2 Welding Processes ...........................................................................................................................9Table 1: Welding Processes and Consumables:............................................................................................. 93.3 Welding Consumables ......................................................................................................................93.4 Storage and Handling of Welding Consumables ..............................................................................103.5 Equipment .....................................................................................................................................103.6 Personnel.......................................................................................................................................11

4. QUALIFICATION OF WELDING PROCEDURES ............................................................................................124.1 Welding Procedure Specifications ...................................................................................................124.2 Welding Procedures - Essential Variables ........................................................................................134.3 Procedure Qualification Test Welds.................................................................................................13Table 2: Extent of testing complete butt weld: ............................................................................................. 14Table 3: Extent of testing for full penetration repair: ................................................................................... 15Table 4: Extent of testing for partial penetration repair: .............................................................................. 15Table 5: Extent of testing for single pass cap repair .................................................................................... 164.4 Mechanical Testing of Welding Procedure Qualification test welds ..................................................16Table 6: Charpy requirements weld testing: ................................................................................................. 17Table 7: Hardness value requirements: ........................................................................................................ 174.5 Permitted Welding Procedure Qualification retests ..........................................................................184.6 Failure Of Welding Procedure Qualification Tests ............................................................................184.7 Brazing and aluminothermic welding of anodic bonding leads .........................................................18Figure 1: Requirements for hardness traverse and impressions ................................................................. 194.8 Weld Procedure Qualification Record(s) ..........................................................................................20Table 8: Checklist WPQ Records.................................................................................................................... 20

5. QUALIFICATION OF WELDERS ..................................................................................................................215.1 General ..........................................................................................................................................215.2 Welder Certificate...........................................................................................................................215.3 Re-qualification of welders .............................................................................................................225.4 Anode cable pin brazers .................................................................................................................225.5 Welder qualification: weld inspection and testing ............................................................................22Table 9: Welder Qualification Tests Requirements per Welder ................................................................... 22

6. PRODUCTION WELDING...........................................................................................................................236.1 General ..........................................................................................................................................236.2 (Line) Pipe Preparation ...................................................................................................................236.3 Alignment.......................................................................................................................................23Table 10: Permitted misalignment of surfaces (EN 12732:2000 Table G1) ................................................... 246.4 Weather Protection ........................................................................................................................246.5 Tack Welds ....................................................................................................................................246.6 Stray Arcs.......................................................................................................................................246.7 Inter-Run Cleaning..........................................................................................................................246.8 Preheat and Interpass Temperature ...............................................................................................246.9 Partially completed welds ...............................................................................................................256.10 Post-Weld Heat Treatment ..............................................................................................................256.11 Material Traceability and Weld Identification ...................................................................................256.12 Production Weld Tests ....................................................................................................................26


7. REPAIR WELDING ....................................................................................................................................277.1 General ..........................................................................................................................................277.2 Defect Removal..............................................................................................................................277.3 Inspection of Weld Repairs .............................................................................................................277.4 Record of Weld Repair....................................................................................................................287.5 Weld Repair Rate ...........................................................................................................................28

8. INSPECTION AND TESTING OF PRODUCTION WELDS................................................................................298.1 Visual Inspection ............................................................................................................................298.2 Non-destructive Testing ..................................................................................................................298.3 Acceptance Criteria NDT .................................................................................................................29

9. RADIOGRAPHY ........................................................................................................................................309.1 Radiographic Procedures................................................................................................................309.2 Procedure Radiographs ..................................................................................................................309.3 Production Radiography .................................................................................................................309.4 Radiation Protection .......................................................................................................................319.5 Qualification of Radiographers........................................................................................................319.6 Film Identification...........................................................................................................................319.7 Film Processing ..............................................................................................................................319.8 Storage of Unexposed films ............................................................................................................319.9 Storage of Radiographs ..................................................................................................................32

10. MANUAL ULTRASONIC TESTING ................................................................................................................3311. AUTOMATED ULTRASONIC TESTING (AUT) ................................................................................................34

11.1 Approval of Contractor, Operators and System ................................................................................3411.2 AUT System ....................................................................................................................................3411.3 Calibration Block for pulse-echo and through-transmission technique .............................................35Table 11: Tolerances of reflectors: .................................................................................................................. 3511.4 Calibration time of flight diffraction technique: ................................................................................36Table 12: Tolerances of notches:..................................................................................................................... 3611.5 Procedure ......................................................................................................................................3611.6 Inspection ......................................................................................................................................3711.7 Pulseecho and through transmission technique............................................................................3711.8 Time of flight diffraction..................................................................................................................3711.9 Repeat inspection ..........................................................................................................................3711.10 Surface condition and Temperature ...............................................................................................3711.11 Couplant .......................................................................................................................................3811.12 Ultrasonic equipment pulse-echo and through transmission...........................................................3811.13 Ultrasonic equipment TOFD ........................................................................................................3811.14 Probes ..........................................................................................................................................3811.15 Monitor/display .............................................................................................................................3811.16 Storage .........................................................................................................................................3811.17 Qualification of AUT system ...........................................................................................................3911.18 Inspection of Weld Repairs ............................................................................................................39

12. SURFACE EXAMINATION ..........................................................................................................................4012.1 Magnetic Particle Inspection (MPI) .................................................................................................4012.2 Dye Penetrant Inspection (DPI) ......................................................................................................40


13. INTERPRETATION AND ACCEPTANCE CRITERIA FOR N.D.T. .......................................................................4113.1 Acceptance Criteria Visual .............................................................................................................41Figure 2: Angle of incidence between parent metal and weld ...................................................................... 4113.2 Acceptance Criteria Radiography ...................................................................................................4113.3 Acceptance Criteria Manual Ultrasonic Testing ...............................................................................4113.4 Mechanised Pulse Echo + TOFD: Interpretation and sizing of weld defects .....................................4113.5 Acceptance Criteria Mechanised Pulse Echo + TOFD ......................................................................4213.6 Acceptance Criteria Magnetic Particle Inspection ...........................................................................4213.7 Acceptance Criteria Dye Penetrant Inspection ................................................................................42

14. REPORTING OF N.D.T. .............................................................................................................................4314.1 General .........................................................................................................................................4314.2 Specific MPI 4314.3 Specific Dye Penetrant............................................................................................................................. 4314.4 Specific Ultrasonic.................................................................................................................................... 4314.5 Specific AUT 4314.6 Specific Radiographic: ............................................................................................................................. 44

15. DOCUMENTATION ...................................................................................................................................4515.1 General .........................................................................................................................................4515.2 Initial Submissions ........................................................................................................................4515.3 Final Documentation .....................................................................................................................4515.4 Storage by CONTRACTOR ...............................................................................................................4615.5 Delivery Documentation ................................................................................................................46

APPENDIX 1: MECHANICAL TEST REQUIREMENTS PIPE WELDS .................................................................47Appendix 1A Sample locations mainline weld .................................................................................. 47Appendix 1B Sample locations Full Penetration Repair ................................................................... 47Appendix 1C Sample locations Partial Penetration Repair .............................................................. 48Appendix 1D Sample locations Cap Repair....................................................................................... 48APPENDIX 2: IMPACT TESTING DETAILS ....................................................................................................49Appendix 2A Charpy details mainline weld and full penetration repair .......................................... 49Appendix 2B Charpy details partial penetration repair .................................................................... 49APPENDIX 3: HARDNESS TESTING DETAILS ..............................................................................................50APPENDIX 4: RADIOGRAPHIC ACCEPTANCE CRITERIA:...............................................................................51APPENDIX 5:MANUAL ULTRASONICS ACCEPTANCE CRITERIA ....................................................................52APPENDIX 6:Mechanised Pulse Echo + TOFD Acceptance Criteria .............................................................53Acceptance criteria based on good workmanship ............................................................................................. 53


1. INTRODUCTION1.1 GENERAL

GDF SUEZ E&P Nederland B.V. (GDF SUEZ) is a company producing hydrocarbons in the Dutch sectorof the North Sea. For this purpose several production and treatment facilities have been installedalong with connecting pipelines.

1.2 SCOPE1.2.1 The purpose of this document is to define the minimum requirements for the approval of welding

consumables, welding processes, welding operators as well as production welding and weldinspection of carbon steel pipelines in compliance with and in addition to the requirements of EN12732:2000, NEN 3650-2:2003, and EN 288-9:1999.

1.2.2 A Scope of Work will be issued giving project specific requirements which shall include design detailsand the requirement (or not) for Nickel content and CTOD testing.

1.3 QUALITY ASSURANCE1.3.1 CONTRACTOR shall have in operation an approved Quality System based on the requirements of EN-

ISO 3834 Parts 1, 2 and 4: 2006 (see also table 2 in EN 12732:2000).1.3.2 CONTRACTORs Quality Manual(s) shall be submitted for review, by GDF SUEZ, as part of his bid

documents.

1.4 QUALITY PLAN1.4.1 CONTRACTOR shall submit a Quality Plan, based on his Quality Manual (s), covering all operations to

GDF SUEZ for approval. CONTRACTOR's subsequent Quality Control of the work shall strictly adhereto the agreed Quality Plan.

1.4.2 Quality Plan shall show hold, witness, review, monitor and approve points for GDF SUEZ andCERTIFYING AUTHORITY. Regarding inspection, the Quality Control Plan shall include: A flowchart illustrating each inspection point and its relative location in the procedure cycle,

where conformance of characteristics is verified. The characteristics to be inspected at each inspection point, the procedures and acceptance

criteria to be used. The procedures shall be provided to GDF SUEZ, as requested. Copies of specific forms used by CONTRACTOR to record the results of each inspection.

1.4.3 CONTRACTOR shall maintain quality records as documentary evidence of compliance with qualityrequirements. Quality records shall be available to GDF SUEZ for analysis and review.

1.4.4 All CONTRACTOR inspection systems shall be subject to evaluation and checks by GDF SUEZ toensure that the system is effectively applied and meets the requirements of this specification.

1.4.5 CONTRACTOR shall employ experienced and competent supervisors to ensure that both the standardof workmanship and the quality of materials used comply with the requirements of this specification.

1.5 INSPECTION NOTICE1.5.1 CONTRACTOR shall give GDF SUEZ and CERTIFYING AUTHORITY inspectors at least five working days

notice of the time and location of fabrication, inspection and testing work. All production shall besubject to inspection by GDF SUEZ and/or the CERTIFYING AUTHORITY.

1.5.2 Intermediate inspections and/or examinations carried out or stage approvals given by GDF SUEZ orthe CERTIFYING AUTHORITY do not absolve the CONTRACTOR from his responsibility that thematerial(s), welding and testing have to comply fully with all rules, regulations and specifications.


1.6 TERMS AND DEFINITIONS

The following terms and definitions apply in this Specification:

GDF SUEZ GDF SUEZ E&P Nederland B.V. or its nominatedrepresentative

CONTRACTOR Engineering and Installation Contractor appointed by GDFSUEZ

CERTIFYING AUTHORITY Any authority required by law and/or as nominated by GDFSUEZ in accordance with the Contract for which certificatesshall be obtained before the work shall be accepted by GDFSUEZ as well as those persons acting as its representatives.

shall indicates a mandatory requirement.

should indicates a preferred method.

1.7 ABBREVIATIONSThe following abbreviations have been used and apply in this Specification:AUT Automatic Ultrasonic TestingCSWIP Certification Scheme for Welding & Inspection PersonnelCW Centre (line) of WeldCTOD Crack Tip Opening DisplacementDN Diameter NominalDPI Dye Penetrant InspectionFCAW Fluxed Core Arc WeldingFL Fusion LineGMAW Gas Metal Arc WeldingGTAW Gas Tungsten Arc WeldingHAZ Heat Affected Zone of Weld.IQI Image Quality IndicatorsLR Latest RevisionMAG Metal Active Gas (welding)MIG Metal Inert Gas (welding)MMAYS Materials Maximum Allowable Yield StrengthMMATS Materials Maximum Allowable Tensile StrengthMPI Magnetic Particle InspectionMRB Manufacturing Record BookNDT Non Destructive Testing.PAM Portable Arc MonitoringPO Purchase OrderPWT Production Weld TestSAW Submerged Arc WeldingSMAW Shielded Metal-Arc WeldingSMTS Specified Minimum Tensile StrengthSMYS Specified Minimum Yield StrengthSVGA Super Video Graphics ArrayTOFD Time of Flight DiffractionUT Ultrasonic TestingWPQ(R) Welding Procedure Qualification (Records)WPS Welding Procedure SpecificationWPT Welding Production Test


2. REFERENCED CODES, STANDARDS AND SPECIFICATIONS

2.1 CODES AND STANDARDS2.1.1 All Work covered by this Specification shall be performed by CONTRACTOR, as a minimum, in

accordance with the requirements of the following referenced codes and standards;

NEN 3650-2:2003 Requirements for Steel Pipeline Transportation Systems.NEN 3653:2009 Methods for the determination of NDE acceptance criteria for defects in pipeline girthwelds.EN 12732:2000 Gas supply systems-Welding Steel pipe work - Functional requirements.API 1104: 2005 Errata1 2007

Welding of Pipelines and Related FacilitiesAlternative Acceptance Standards for Girth Welds

ASME BPV 5 Boiler and pressure vessel code, section 5: article 4, mandatory appendices numbers Iand II and article 5 mandatory appendices numbers I and II (July 2001)BS 7448:pt 2.:1997 Fracture mechanics toughness tests: CTOD.EN 10045-1:1990 Metallic materials Charpy impact test Part 1: Test method.EN 10204:2004 Metallic Products Types of inspection documents.EN 10208-2:2009 Steel Pipes for pipelines in combustible fluids Technical delivery conditions Part 2:Pipes of requirement class B.EN 10246-17:2000 Non-destructive testing of steel tubes Part 17: Ultrasonic testing of tube ends ofseamless and welded steel tubes for the detection of laminar imperfections.EN 10246-18:2000 Non-destructive testing of steel tubes Part 18: Magnetic particle testing of tube endsof seamless and welded steel tubes for the detection of laminar imperfections.EN 1043-1:1995 Destructive test on weld in metallic materials-Hardness testing-Part 1: Hardness teston arc welded joints.EN 12668-2:2001 Characterization and verification of ultrasonic examination equipment. Part 2: Probes .EN 12668-3:2000 Characterization and verification of ultrasonic examination equipment. Part 3:Combined equipment.EN 1290:1998A2:2003 Non-destructive examination of welds Magnetic particle examination of welds.EN 1291:1998A2:2003 Non-destructive examination of welds- Magnetic particle testing Acceptance levels.EN 1321:1997 Destructive tests on welds in metallic materials Macroscopic and microscopicexamination of welds.EN 1418:1998

Welding personnel. Approval testing of welding operators for fusion welding andresistance weld setters for fully mechanized and automatic welding of metallicmaterials

EN 1435:1997A2:2003 Non-destructive examination of welds Radiographic examination of welded joints.EN 15609-1:2004 Specification and qualification of welding procedures for metallic materials Weldingprocedure specification Part 1: Arc welding.EN 1668:1997 Welding consumables Rods, wires and deposits for tungsten inert gas welding of non-alloy and fine grain steels Classification.EN 1714:1998 Non-destructive examination of welds Ultrasonic examination of welded joints.EN 24063:1992 Welding, brazing, soldering and braze welding of metals Nomenclature of processesand reference numbers for symbolic representation on drawings.EN 25580:1992 Specification for minimum requirements for industrial radiographic illuminators for non-destructive testingEN 287-1:2004A2:2006 Approval testing of welders Fusion welding Part 1: Steels.

EN 288-9:1999Specification and approval of welding procedures for metallic materials Part 9:Welding procedure test for pipeline welding on land and offshore site butt welding oftransmission pipelines.

EN 462-1:1995 Non-destructive testing Image quality of radiographs Part 1: Image qualityindicators (wire type) Determination of image quality value


EN 473:2008 Qualification and certification of NDT personnel. General principals.EN 499:1995 Welding consumables Covered electrodes for manual metal arc welding of non-alloyand fine grain steels Classification.EN 571-1:199 Non-destructive testing-Penetrant testing-Part 1: General principals.EN 583-1:1999 Non-destructive testing-Ultrasonic examination -Part 1: General principals.EN 583-6:2009 TOFD technique as a method for detection and sizing of discontinuities.

EN 756:2004Welding consumables. Solid wires, solid wire-flux and tubular cored electrode-fluxcombinations for submerged arc welding of non alloy and fine grain steels.Classification

EN 757:1997 Welding consumables Covered electrodes for manual metal arc welding of highstrength steels Classification.EN 760:1996 Welding consumables Fluxes for submerged arc welding Classification.EN 875:1995 Destructive tests on welds in metallic materials-Impact tests-Test specimen location,notch orientation and examination.EN 895:1995 Destructive tests on welds in metallic materials Transverse tensile test.EN 910:1996 Destructive tests on welds in metallic materials Bend tests.EN 970:1997 Non destructive examination of fusion welds visual examination.EN-ISO 6892-1:2009 Metallic materials. Tensile testing Part 1:. Method of test at room temperatureEN-ISO 14175:2008 Welding consumables Shielding gases for arc welding and cutting.EN-ISO 14341:2008 Welding consumables Wire electrodes and deposits for gas-shielded metal arcwelding of non-alloy and fine grain steels Classification.EN-ISO 17632:2004 Welding consumables Tubular cored electrodes for gas shielded and non-gasshielded metal arc welding of non-alloy and fine grain steels Classification.EN-ISO 3834-1:2006 Quality requirements for welding Fusion welding of metallic materials Part 1:Criteria for the selection of the appropriate level of quality requirements.EN-ISO 3834-2:2006 Quality requirements for welding Fusion welding of metallic materials Part 2:Comprehensive quality requirements.EN-ISO 3834-4:2006 Quality requirements for welding Fusion welding of metallic materials Part 4:Elementary quality requirements.ISO 17025:2005 General requirements for the competence of testing and calibration laboratories.ISO 3690:2000 Welding and allied processes -- Determination of hydrogen content in ferritic steel arcweld metalISO 9001 Quality Management Systems : Requirements

2.1.2 The edition of each code and standard stated in this section shall apply; together with all publishedamendments. Where conflict occurs between the requirements of this Specification and referencedcodes and standards, the most stringent requirements shall apply. Where any of the documents arerevised and the revision affects the scope of supply, CONTRACTOR shall notify GDF SUEZ in writingimmediately.


3. GENERAL3.1 SCOPE3.1.1 All welding shall, be carried out in accordance with the requirements of EN 12732:2000 NEN 3650-

2:2003, and EN 288-9:1999, augmented with the additional requirements detailed in thisspecification.

3.2 WELDING PROCESSES3.2.1 All welding shall be by Manual, Semi-Automatic or Automatic Shielded Metal-Arc Welding (SMAW),

Fluxed Core Arc Welding (FCAW), Gas Metal Arc Welding (GMAW), Gas Tungsten Arc Welding (GTAW)or Submerged Arc Welding (SAW). Other processes may be agreed by GDF SUEZ; however in suchcases the inspection and testing requirements may be varied as deemed necessary by GDF SUEZand/or CERTIFYING AUTHORITY.

Table 1: Welding Processes and Consumables:Type of Process Procedure no.

according to:EN 24063

Consumables shall be in accordancewith:

Shielded Metal Arc Welding 111 EN 499 & EN 757Gas Metal Arc Welding 135, 141 EN-ISO 14341 & EN 1668Flux-Cored Arc Welding 114, 136, 138 EN-ISO 17632Shielding gases EN-ISO 14175:Submerged Arc Welding 12 EN 756Fluxes for submerged arcwelding

12 EN 760

3.2.2 FCAW process shall be thoroughly controlled at all times by CONTRACTOR to avoid any excessivescatters in the mechanical properties (and specially impact properties) of weld deposits. In that view,mechanical test results of qualification test welds shall show sufficient safety margins against therequirements of this specification. The GDF SUEZ reserves the right to reject such a process when itsreliability is not satisfactory.

3.3 WELDING CONSUMABLES3.3.1 Welding consumables shall be selected to ensure that they overmatch the maximum allowable yield

and tensile values of the projects line pipe. The Materials Maximum Allowable Yield Strength(MMAYS) shall be overmatched by at least 50 Mpa and the Materials Maximum Allowable TensileStrength (MMATS) shall be overmatched by at least 30 Mpa. As such the minimum weld metals;1) Yield Strength shall be the line pipes SMYS + 120 Mpa + 50 Mpa = 170 Mpa2) Tensile Strength shall be the line pipes SMTS + 120 Mpa + 30 Mpa.= 150 Mpa.

3.3.2 The deposited weld metal, shall exhibit mechanical properties greater than, and chemical analysissimilar to (taking into account any specific property requirements), those of the actual base material.For the welding of the carbon steel line pipe and parts, the nickel content of deposited weld metalshall not exceed 1%.

3.3.3 When specified in the Scope of Work the root pas shall be welded with a consumable which containsless than 0.25% Nickel.

3.3.4 All batch test certificates (according to EN 10204:2004, type 3.1) for welding filler materials showingall test results, including impact testing, all weld tensile testing and chemical analyses, shall beprovided by CONTRACTOR for each production batch of consumables in use.

3.3.5 Low hydrogen consumables shall give a maximum diffusible hydrogen content of 5 ml per 100 gramsof Weld Metal determined with the method specified by ISO 3690:2000. The electrodes shall besupplied in vacuum packing. Moreover, they shall be guaranteed against moisture absorption for 8hours after pack opening.


3.3.6 Cellulosic coated electrodes may be used provided that special weld procedures preventing hydrogeninduced cracking are established.

3.3.7 Special considerations are to be made when welding steels with a SMYS above 420MPa to ensuresafety against cold cracking in the HAZ and/or weld metal. Attention must also be paid to therequirements for overmatching yield and tensile strength.

3.3.8 Welding consumables for other processes than manual or mechanised arc welding may requirespecial consideration with respect to certification, handling and storage (see also 3.4 of thisSpecification).

3.4 STORAGE AND HANDLING OF WELDING CONSUMABLES3.4.1 The minimum requirements for the care, storage, control and handling of consumables and flux (for

SAW) shall be those of the relevant consumable manufacturer. CONTRACTOR shall provide a detailedstorage, control and handling procedure to GDF SUEZ. Any proposed re-cycling of flux is subject toGDF SUEZ approval.

3.4.2 Different grades and batches shall be individually identified and completely separated from eachother.

3.4.3 Low hydrogen welding consumables shall be supplied in sealed, dirt and moisture-resistantpackages. Damaged packages and any consumables showing signs of damage, deterioration,corrosion or any other contamination shall not be used.

3.4.4 Cellulosic consumables shall always be kept in their original container.3.4.5 Consumables shall be stored and handled at all times in such a way as to avoid damage and

contamination to them and their containers. Consumables in open containers shall be protectedfrom environmental moisture changes.

3.5 EQUIPMENT3.5.1 All welding shall be performed using equipment of a type that has proved to be reliable and suitable

for the work being performed. Equipment used for production welding shall be of the samespecification to that used to qualify the welding procedure. Cable lengths shall also reflect thoseused in production.

3.5.2 CONTRACTOR shall ensure and demonstrate that all welding machines are properly earthed to avoidthe occurrence of stray arcing. CONTRACTOR shall provide earth clamps of an approved design andshall ensure only insulated electrode holders are used.

3.5.3 Current certification/calibration certificates for all testing equipment shall be provided to GDF SUEZfor review prior to use. CONTRACTOR shall maintain a system for calibration control for all equipment.

3.5.4 Independent means shall be provided by CONTRACTOR for the accurate monitoring of all weldingparameters including current, voltage, welding speed, thermal input, preheat, interpass temperatureand, for fine wire and gas shielded welding, process-wire feed speed, gas flow rate and gascomposition (especially oxygen level) etc. These parameters shall be measured and recorded on asampling basis (to be agreed) during each shift.

3.5.5 Where (semi-) automatic welding systems are utilised the equipment shall be designed to providecurrent cut-off linked to wire feed speed in order to minimise the risk of copper contamination at stoppoints. This shall be proven during procedure qualification and also on production welding equipmentat start of production (using a sacrificial pipe sample).

3.5.6 Where copper tips are used, CONTRACTOR shall have a control procedure in place to ensure that nowelding shall be allowed to continue once a copper touch has been discovered. Further actions onthis subject shall be agreed by CONTRACTOR and GDF SUEZ prior to commencement of production.


3.6 PERSONNEL3.6.1 CONTRACTOR's welding supervisors shall have full knowledge of all specification requirements and

the applicable standards and codes and shall be qualified according to EN 12732:2000 Section11.3

3.6.2 Current copies of all pertinent documentation, such as this Specification and approved WeldingProcedure Specifications, shall be in the English language and shall be at the disposal of the weldingcrews and inspection personnel during all operations.

3.6.3 All welders shall be qualified as set out in Section 5 of this Specification.3.6.4 All CONTRACTORs welding inspection personnel shall be qualified according to a minimum of CSWIP

3.1 Welding Inspector or a GDF SUEZ approved equivalent and be in possession of a current eyesightcertificate in accordance with EN 970 and EN 473:2008.

3.6.5 Non Destructive Examination personnel shall be qualified in accordance with EN 473:2008 and asdetailed in the NDT sections of this specification.


4. QUALIFICATION OF WELDING PROCEDURES4.1 WELDING PROCEDURE SPECIFICATIONS4.1.1 CONTRACTOR shall propose detailed Welding Procedure Specifications (WPS) for all production and

proposed/anticipated repair welding. Proposed WPSs along with a matrix detailing all procedures andthe amount of tests to be carried out shall be submitted to GDF SUEZ and the CERTIFYINGAUTHORITY for review prior to welding of the test welds.

4.1.2 The weld procedure shall be proven, if required, to be suitable for reeling and, if deemed necessaryby GDF SUEZ and/or CERTIFYING AUTHORITY, extra tests may be required to prove such suitability.

4.1.3 Any change(s) to any of the proposed WPS's shall be proposed/discussed with GDF SUEZ and theCERTIFYING AUTHORITY before being implemented.

4.1.4 Welding Procedure Specifications (WPS) shall be prepared on forms in accordance with EN 15609-1:2004 and shall contain, as a minimum, the following information:a) Material specification of base materials.b) Welding process and whether manual or automatic.c) Qualified Wall thickness and diameter range (see Section 4.2).d) Geometry of weld groove including dimensional tolerances.e) Root gap (if any) showing allowable tolerances.f) Welding position and direction.g) Filler metal name/type/classification/diameter per pass/layer.h) Name/type/specification/classification/composition of flux and/or flows.i) Gas shielding flow and gas backing (purging) flow (if any).j) Backing strips (permanent backing strips are not allowed).k) Number and sequence of all passes (indicate stringer or weave beads and maximum weave

width).l) Welding current* and voltage range* and polarity. If pulse welding is used, the pulse range.m) Travel speed and electrode run-out length for each pass and permitted range.n) Heat input range*.o) Minimum preheat and maximum inter-pass temperatures and where measured.p) Post-weld heat treatment (if any).q) Method of cleaning and cutting.r) Method of joint set-up including clamp type.s) (Repairs) method of defect removal and preparation of weld area.t) (Repairs) pre-heat prior to gouging.u) (Repairs) minimum and maximum opening sizes.* Note: Recorded ranges shall be included in the WPS, these shall not include % allowances,

these must be noted separately in the WPS.4.1.5 All WPS's, including all procedures for repair welding, shall be welded/qualified in accordance with

the requirements of EN 288-9:1999 and this specification.4.1.6 All welding and testing required to qualify a procedure shall be performed in the presence of GDF

SUEZ, who shall receive ten (10) days minimum advance notice of the date qualification welding is tostart.

4.1.7 GDF SUEZ shall witness all non-destructive examinations and destructive testing and shall reviewand approve all related results. All mechanical testing shall be carried out by a certified (see ISO/IEC17025:1999) testing facility subject to prior approval of GDF SUEZ.

4.1.8 Production welding shall not commence until all Welding Procedure Qualifications (WPQ) have beenaccepted/approved by GDF SUEZ and the CERTIFYING AUTHORITY.


4.2 WELDING PROCEDURES - ESSENTIAL VARIABLES4.2.1 An approval of a WPS obtained by a manufacturer is valid in workshops or sites under the same

technical and quality control of that manufacturer (EN 288-9:1999 8.2).Essential variables shall be as defined in EN 288-9:1999 with the addition of those detailed in thisspecification. Any changes outside the permissible limits of the essential variables shall necessitatere-qualification of the welding procedure.

4.2.2 Additional requirements for essential variables:1. Filler metal: clause 3.3.3 of this specification replaces clauses 8.4.4 and 8.4.5 of EN 288-

9:1999.2. Heat input: clause 4.3.5 of this specification replaces clause 8.4.7 of EN 288-9:1999.3. Any change in size/diameter of welding consumable: replaces clause 8.5.1 of EN 288-9:1999.4. The use of water quenching/cooling (for a rapid reduction of the material temperature for NDT

or any other reason).5. The use of hot-starts.

4.3 PROCEDURE QUALIFICATION TEST WELDS4.3.1 CONTRACTOR shall perform all procedure qualification test welds in accordance with EN 288-9:1999

and the relevant sections of this specification4.3.2 Test welds shall be identified with a unique number, which shall be hard-stamped in the pipe. All test

samples shall be hard-stamped with the GDF SUEZ inspectors mark prior to removal from the testpipe. All marking shall be recorded by CONTRACTOR and witnessed by GDF SUEZ and theCERTIFYING AUTHORITY.

4.3.3 All pipe for qualification test welds shall be line pipe selected from production pipe manufactured forthis project and from each steel manufacturer or source of supply. Contractor shall check this pipefor identification and conformity to the line pipe specifications and relevant certificates (EN 10208-2and EN 10204). The pipe selected for procedure welding should be supplied from the heat or lotexhibiting one of the highest carbon equivalents as proven by the product analysis during line pipeproduction.

4.3.4 At least one complete weld shall be made and tested to qualify each pipe to pipe welding procedureand one weld for pipe to fitting welding procedure. For small diameter pipe, additional welds shall bemade where necessary to provide sufficient material for testing. When manual welding is to be used,a minimum of one complete test joint is to be made for each Welding Procedure. For semi-automaticor automatic welding equipment, a minimum of three consecutive complete test joints shall to bemade (all of which must be acceptable for NDT).

4.3.5 Procedure qualification test welds, and all repair test welds, shall be carried out between two piecesof pipe (each with a minimum length of 500mm), which shall be restrained. Weld ProcedureQualifications shall be completely monitored and recorded by CONTRACTORs QC department usingcalibrated Portable Arc Monitoring (PAMs or ALX unit) equipment. All as-runs recording, forexample, voltage, amperage, pre-heat and inter-pass temperature (refer to 6.8 for the requirements),travel speed, electrodes, position, welder, polarity, gas composition etc. shall be included in thedocumentation package submitted along with the NDT and Mechanical Test Results, prior toapproval of the WPQ and final WPS.

4.3.6 For qualification of delays between runs refer to 6.9 of this specification.4.3.7 Where the use of water quenching/cooling is proposed (for a rapid reduction of the material

temperature to allow Automated Ultrasonic Testing), this shall be qualified during procedurequalifications and noted on the ultimate WPS.

4.3.8 The test welds shall be non-destructively inspected in accordance with the relevant NDT sections ofthis Specification. Should the test weld not meet the stated acceptance criteria it shall not besubmitted for mechanical testing.

4.3.9 NDT of procedures shall take place a minimum of 24 hours after completion of welding.


4.3.10 Welds, which pass non-destructive testing shall be tested in full accordance with EN 288-9:1999 andthis specification. Samples shall be removed from the locations described in Appendix 1.

4.3.11 The following tables show the minimum amount of procedures to be qualified as well as theinspection and testing requirements that are in compliance with or in addition to EN 288-9:1999.Consideration should be taken with EN 288-9:1999 Section 8 with regards to qualification ranges.Typical examples are given for repair excavation requirements.

Table 2: Extent of testing complete butt weld:

Test Piece Type of inspection Extent of inspection NoteVisual examination 100% Section 8Radiographic examination 100% Section 9Ultrasonic examination 100% Section 10/11MPI examination 100% Section 12

Type of test Extent of testing NoteTransverse tensile test 2 specimens See 4.4.1All weld tensile test 4 specimens See 4.4.2Impact test 4 sets cap &

4sets root (>20mm)See 4.4.3

Macro examination 2 test specimens See 4.4.4Hardness test 2 test specimens See 4.4.5Bend test 2 root & 2 face See 4.4.6

Butt-weldAt least 1 completeweld per process(see 4.3.4)Note: For Doublesided SAW sidebends may be usedto replace root andface bends.

CTOD (if required in the Scope ofWork)

9 (3x CW + 6x FL) See 4.4.7

CW

Th

CWRoot Pass

Fill(s)

Cap

Hot Pass

Th

External Cap

Internal Cap

Root Area

Typical examples of mainline and double joint welds are shown here.


Table 3: Extent of testing for full penetration repair:


Type of test Extent of testing NoteTransverse tensile test 1 specimens See 4.4.1Impact test 4 sets cap &

4 sets root(>20mm)See 4.4.3

Macro examination 1 test specimens See 4.4.4Hardness test 1 test specimens See 4.4.5

Full PenetrationRepair weld1 off

Bend test 2 root & 2 face See 4.4.6CW

Th

CW

Root Pass

Fill(s)

Cap

Hot Pass

Original Weld HAZ

Table 4: Extent of testing for partial penetration repair:


Type of test Extent of testing NoteTransverse tensile test 1 specimens See 4.4.1Impact test 4 sets cap See 4.4.3Macro examination 1 test specimens See 4.4.4Hardness test 1 test specimens See 4.4.5

PartialPenetrationRepair to leave aminimum of3mm parentmetal.1 off

Bend test 2 face See 4.4.6CW

CW

To Be Qualified =3 mm

30 10To Be Qualified

Original Weld Metal

Original Weld HAZExcavation Boundary


Table 5: Extent of testing for single pass cap repair

Test Piece Type of inspection Extent of inspection NoteVisual examination 100% Section 8Radiographic examination 100% Section 9MPI examination 100% Section 12

Type of test Extent of testing NoteMacro examination 1 test specimens See 4.4.4Hardness test 1 test specimens See 4.4.5

Single Pass CapRepair1 off

Bend test 1 face See 4.4.6CW

Th

CW

Single Pass Cap Repair

Original Weld Metal

4.3.12 Repairs shall be carried out centred at the 6 oclock position. All stages of the repair weldingqualification (including gouging {note-gouging pre-heat to be qualified} and grinding of repairexcavation see Section 7.2.3) shall be carried out with the test pipe in its required fixed position.The ends of the pipe shall be closed off and no access to the inside shall be allowed.

4.3.13 Results of procedure qualification testing shall be recorded on WPQ record forms in accordance withEN 288-9:1999 and this specification (see also Section 4.1.4).

4.3.14 Test samples shall be removed from the locations shown in Appendix 1.4.3.15 Welders who weld the procedure(s) may be qualified on acceptance of the procedure(s). However,

where two welders are used on one weld extra samples may be required to comply with therequirements stated in Table 9.

4.4 MECHANICAL TESTING OF WELDING PROCEDURE QUALIFICATION TEST WELDS4.4.1 Transverse Tensile Testing

Two transverse (cross weld) tensile tests shall be performed according to EN 895.If the specimen breaks in the weld metal or HAZ, it shall be considered unacceptable unless it can beproven that the achieved values for Yield Strength and Ultimate Tensile strength are in excess ofthose required for All Weld Tensile Tests as specified in 4.4.2.

4.4.2 All Weld Tensile TestingActual weld properties shall be demonstrated by the performance of All Weld Metal Tensile Tests,parallel to the weld axis. The actual type and size of test specimen is dependent on thediameter/wall thickness of the involved line pipe and the applied type/number of consumables in theinvolved weld.From each procedure 4 round bar test specimens, of the largest possible size, will be tested. Twospecimens shall be taken as close as possible to the weld root area and two specimens as close aspossible to the weld cap area.After testing, a macro shall be prepared from the broken test specimen. If the sample demonstratesthat the test included any FL/HAZ or pipe material then the test will be considered invalid and shallbe re-done.The resulting Yield Strength shall be greater than the highest recorded yield strength of the basematerial (see Section 3.3) and as a minimum this shall exceed the SMYS by at least 100 Mpa.


The resulting Tensile Strength shall be greater than the highest recorded tensile strength of the basematerial (see Section 3.3) and as a minimum this shall exceed the SMTS by at least 80Mpa.

. With GDF SUEZ approval, these tests may be substituted with cross weld tensile tests with fullstress/strain curves.

4.4.3 Charpy V-Notch impact testingTest specimens shall be taken and prepared in accordance with EN-10045-1 in such a way that theaxis of the notch is perpendicular to the pipe surface. Test specimens and testing for impact testshall be in accordance with this specification for position and temperature of testing and with EN875 for dimensions and testing (see also Appendix 2).Each set shall comprise of three full size specimens taken with the notch (The notch line shall be cutthrough the pipe thickness) in the following locations, (see Appendix 2A):a) weld centre lineb) weld fusion linec) weld fusion line + 2mmd) weld fusion line + 5mmFor partial penetration repairs the following samples shall be taken, (see Appendix 2B):a) weld fusion line to existing weldb) weld centre linec) weld fusion lined) weld fusion line + 2mmTest specimens with Charpy V-notch shall be used and sampled from 2 mm below the outer surfaceof the pipe and transverse to the weld. When the pipe wall thickness exceeds 20 mm, four more setsare required, in the same circumferential locations, but taken within 2 mm of the inside surface ofthe pipe. The minimum absorbed energy values shall be as stated in Table 6:

Table 6: Charpy requirements weld testing:Specified minimum yield

strength of steel:Average of3 specimens

Single Specimen* TestTemperature

All 50 Joule (J) 40 Joule (J) 20C**

*Note 1: only one single value may be below the average requirement.**Note 2: Unless Design Temperature is lower in which case Design Temperature applies.The percentage [%] shear at the fracture surface shall be recorded and be a minimum of 50%.Refer to the Scope of Work for details.

4.4.4 MacrographyTwo macro sections of the welds shall be prepared and examined in accordance with EN 1321. Thetest pieces shall be polished and etched for macrographic examination of the weld. The weldcross-section shall be examined for good weld profile and sufficient penetration free of significantinclusions or other defects. It shall also serve to confirm the amount of weld passes that have beendeposited and their compliance with the pWPS.

4.4.5 Hardness TestingHardness surveys shall be carried out on both macro sections, in accordance with EN 1043-1. TheVickers method HV10 shall be used, as detailed in Appendix 3. Results of hardness tests shall bebelow the maximum values specified in Table 7. Permanent records of macro sections shall be keptby means of photo-macrographs showing all hardness indentations.

Table 7: Hardness value requirements:

Hardness location Hardness HV10Weld metal and HAZ: root 250Weld metal and HAZ: cap 275


4.4.6 Bend Testing,Specimens and testing for butt joints shall be in accordance with EN 910.The diameter of the former or inner roller shall be 4t and the bending angle shall be 180 for parentmetal with elongation A 20%. For parent metal with elongation < 20% the following formula shall beapplied:

(100 x ts )d = A - tswhered is the diameter of the former or the inner rollerts is the thickness of the bend test specimenA is the minimum tensile elongation required by the material specificationDuring testing, the test specimens shall not reveal any one single flaw > 3 mm in any direction. Flawsappearing at the corners of a test specimen shall be ignored in the evaluation.

4.4.7 Chemical AnalysisQuantitative chemical analyse of the weld cross-section shall be made in the root zone and fillerpasses to verify the chemical elements as per the chemistry requirement of the applicableconsumable specification.

4.4.8 CTOD TestingIf required in the Scope of Work, CTOD testing shall be carried out according to BS 7448:part2.:1997. 3 (three) Centre of Weld samples shall be taken and 6 (six) Fusion Line samples (of which 3may be used). Testing shall be carried out at 0C.

4.5 PERMITTED WELDING PROCEDURE QUALIFICATION RETESTS4.5.1 Welding Procedure Qualification re-tests are not permitted without the approval of GDF SUEZ.4.5.2 Where re-tests are permitted, they shall be limited to:

a) Tensile Tests - if one test fails to comply with the specified mechanical requirements, two furthertest specimens shall be taken.

b) All Weld Tensile - if one test fails to meet the minimum specified requirements for the basematerial, two more tests shall be taken.

c) Hardness Tests - if one test fails to comply with the specified mechanical requirements, twofurther test specimens shall be taken for each one that failed.

d) Bend Tests - if one test fails to comply with the specified requirements, two further testspecimens shall be taken.

e) Charpy-V Notch Impact Tests - if one Charpy value from a set of three test specimens falls belowthe minimum individual value specified in 4.4.3, then three further tests shall be carried out. Allthree re-test specimens shall meet the requirements of 4.4.3 and the mean value of all six testsshall be calculated and shall meet the specified minimum average value.

4.5.3 If any single (permitted) re-test subsequently fails, no further re-testing shall be allowed and the testshall be deemed to have failed (see clause 4.6).

4.6 FAILURE OF WELDING PROCEDURE QUALIFICATION TESTS4.6.1 Should a procedure qualification test fail any of the required visual, non-destructive and/or

mechanical tests or permitted re-tests, it shall be regarded as not complying with the requirements ofthis specification. The cause of failure shall be established, rectified and the WPS revised asappropriate, before the qualification test is repeated.

4.7 BRAZING AND ALUMINOTHERMIC WELDING OF ANODIC BONDING LEADS4.7.1 Full details of the joining technique, proposed procedure and associated equipment shall be

submitted to GDF SUEZ prior to use and be in conformance with the manufacturersrecommendations.


4.7.2 The procedure shall be qualified (in accordance with EN 12732:2000 Annex H) by making threeconsecutive test joints in the presence of GDF SUEZ on materials to be used in production andrepresenting the upper quartile of the carbon equivalent range.

4.7.3 The electrical resistance shall be measured and should not exceed 0.1. The mechanical strength ofthe joint shall be tested by means of a sharp blow from a 1kg. Hammer.

4.7.4 All three joints shall be sectioned and prepared for metallographic examination. The following testsshould be performed on the sections:a) Copper contamination measurement: The depth of copper contamination below the surface of

the pipe material shall be measured metallographically. The fusion line of the weld or brazeshould not be more than 1mm below the pipe surface. Intergranular copper penetration of thepipe material shall not exceed 0.5mm beyond the fusion line when a micro-section isexamined at a magnification not exceeding x50.

b) Hardness survey: Each section shall be tested using a 10kg load. A transverse should bemade across the weld zone as shown below and should consist of at least 6 impressions; twoin the heat affected zone each side of the weld/braze and one in the parent metal each side ofthe weld/braze. The hardness value shall not exceed 325HV 10. See the figure 1:

Note: Hardness impressions 2, 3, 4 and 5 should be entirely within theheat-affected zone and located as close as possible to the fusion boundary

Weld heat affected zone (visible after etching)

1 2

3 4

65

Weld/Braze metal Parent Metal Surface

Figure 1: Requirements for hardness traverse and impressionsfor brazing and aluminothermic welding.


4.8 WELD PROCEDURE QUALIFICATION RECORD(S)The Weld Procedure Qualification Record(s) shall contain the following documentation and beprecluded with a check list sheet (see example below) showing the contents of each package:Table 8: Checklist WPQ Records

WPQ: 010-013168.3mm x 18.3mm (L450QO PSL2) Pipe to Pipe

Designation: Mainline WeldingWPQ (Pre) WPS As Runs Weld Visual Inspection Report Weld Radiographic Inspection Report Weld Ultrasonic Inspection Report Weld M.P.I Report Mechanical Test Results Material Certificate(s) Consumable Certificate(s) Material Cutting List Welders Details NDT Technician Qualifications

Following a final review of the packages, each checklist shall be signed off by GDF SUEZ,CONTRACTOR and the CERTIFYING AUTHORITY.


5. QUALIFICATION OF WELDERS5.1 GENERAL

5.1.1 The use of pre-qualified welders is not allowed. Each welder or welding machine operator shallbe qualified in accordance with EN 287-1:2004 or EN 1418:1998 and this specification prior tothe start of production welding by making a test weld using the qualified welding procedure. Thiswill comprise of a minimum of one half-circumference weld for welder qualifications and forrepair welders sufficient weld to allow for removal of all mechanical test samples (note thatdefect removal by gouging and grinding forms part of repair welder qualification). The testwelds shall be performed with the pipe in the same position as will be found in productionwelding. Each welding machine operator (for submerged arc welding) shall produce onecomplete weld.

5.1.2 CONTRACTOR shall ensure that only qualified welders and welding operators are employed duringconstruction, welding within the permissible range, position and process for which they are qualified.

5.1.3 The following applications shall be qualified: Welding Process Welding Position Filler Material (including combinations). The welder is only allowed to use the type of filler

material for which he has been approved (i.e. cellulosic only qualifies cellulosic) Pipe Material Girth weld or weldolet

5.1.4 The following ranges can be qualified in accordance with EN 12732: DN 50 qualifies all diameters up to and including DN 100 (category small diameter) DN 150 qualifies all diameters between DN 100 and DN 250 (category medium diameter) DN 400 qualifies equal to or greater than DN 250 (category large diameter)

5.1.5 If a welder fails a qualification test, the result shall be provided to GDF SUEZ. The welder or weldingoperator may carry out a retest (new test joints of the same type as the rejected one), provided thecause of failure is determined and not attributed to inadequate training. If the retest meets thespecification requirements, the test will be considered satisfactory. Any welder failing a qualificationtest shall not be permitted further testing without prior GDF SUEZ approval and without a period ofappropriate training.

5.2 WELDER CERTIFICATE5.2.1 CONTRACTOR shall operate a scheme for welder qualification certification certificates and welder

identification, which shall be provided to GDF SUEZ for approval prior to the qualification programmecommencing.

5.2.2 The pipeline welder certificate shall be similar to that proposed in EN 287-1. The certificate shallclearly indicate the standard to which the welders certification has been performed, i.e. ThisSpecification/EN12732/EN 287-1.

5.2.3 The duration of validity for the certificate is 6 months. NDT records shall be maintained for thepurpose of extending the validity of the welder certificates.

5.2.4 The original certificate is non-transferable and shall be in the possession of the welder orCONTRACTOR (at the production location) during execution of the work

5.2.5 The original certificates shall be signed by GDF SUEZ.


5.3 RE-QUALIFICATION OF WELDERS5.3.1 Re-qualification of welders or operators is required if any change is made to the welding procedure,

which necessitates re-qualification of said welding procedure.5.3.2 GDF SUEZ reserves the right to require the re-qualification of welders or welding machine operators if

repair rates are encountered in production welding by any one or more operators, which in GDFSUEZ's opinion are excessive (refer also to Section 7.5)

5.4 ANODE CABLE PIN BRAZERSPrior to carrying out production work, each operator shall complete three test joints, witnessed byGDF SUEZ, which should pass the tests for electrical continuity and mechanical strength described inSection 4.5. A list shall be produced identifying all qualified pin brazers and this shall be approvedby GDF SUEZ and displayed at the work location.

5.5 WELDER QUALIFICATION: WELD INSPECTION AND TESTINGEach test weld shall undergo visual inspection, non-destructive testing, and destructive testing inaccordance with the following table. Non-acceptable results shall constitute the rejection of the test.

Table 9: Welder Qualification Tests Requirements per Welder

Test Piece Type of inspection Extent of inspection NoteVisual examination 100% Section 8Radiographic examination* 100% Section 9MPI examination 100% Section 12

Type of test Extent of testing NoteMacro examination 1 test specimen See 4.4.4

Butt Weld orHalf ButtWeld

Bend test 2 root & 2 face See 4.4.6Test Piece Type of inspection Extent of inspection Note

Visual examination 100% Section 8Radiographic examination 100% Section 9MPI examination 100% Section 12


Full andPartialPenetrationRepair

Bend test 2 root & 2 face (FP)2 face (PP)

See 4.4.6

Test Piece Type of inspection Extent of inspection NoteVisual examination 100% Section 8Radiographic examination 100% Section 9MPI examination 100% Section 12


Cap Repair

Bend test 2 face See 4.4.6Test Piece Type of inspection Extent of inspection Note

Visual examination 100% Section 8MPI examination 100% Section 12

Type of test Extent of testing Note

Weldolet

Macro examination 4 test specimen See 4.4.4

*Note: For Automatic Processes (MAG/MIG) when the wall thickness exceeds 8mm UltrasonicExamination shall be carried out in accordance with Section 10 or 11 (in accordance with EN12732).


6. PRODUCTION WELDING6.1 GENERAL6.1.1 Production welding shall not commence until the qualified welding procedures, qualified welders and

qualified inspection personnel lists have been reviewed and approved by GDF SUEZ.6.1.2 At every welding station / location the relevant approved welding procedure specifications (W.P.S.)

and approved welders lists shall be clearly displayed.6.1.3 If the requirements specified in the approved WPSs are not being complied with then this shall be

cause for rejection of the weld or welds in question.

6.2 (LINE) PIPE PREPARATION6.2.1 The weld bevels and adjacent surfaces for a distance of 100 mm shall be free from surface defects,

coating, moisture, grease, paint or rust immediately prior to welding.6.2.2 Line pipe will be supplied by GDF SUEZ with the end preparation as specified in the line pipes

material specification. Should CONTRACTOR elect to use a different bevel approval shall be obtainedfrom GDF SUEZ, and the bevel design shall be incorporated in the weld procedure specifications.

6.2.3 For pipe-to-fitting welds where wall thickness changes are involved, the joint design in accordancewith EN 12732:2000 Annex C shall be provided by CONTRACTOR for GDF SUEZ's review. All changesof section shall have a smooth and uniform finish.

6.2.4 Any pipe bevel showing evidence of end area lamination shall be immediately reported to GDF SUEZin writing and then cut back until the laminated section is removed, and re-bevelled. After re-bevellingthe pipe end shall be wet magnetic particle inspected and ultrasonically inspected over a distance of100 mm from the bevel, in accordance with EN 10246-18 and EN 10246-17, to ensure that nofurther laminations are present. Any linear indication greater than 10 mm in any direction shall because for rejection.

6.2.5 Field bevels shall be made by machine tool (automatic or hand controlled). Thermal cutting is notacceptable. The bevel ends shall be smooth and uniform and dimensions shall be in accordance withthe qualified welding procedure specification.

6.2.6 Burrs, small score marks, indentations or other small defects within the joint preparation shall, at thediscretion of GDF SUEZ be ground out, otherwise the joint shall be re-prepared. Any damage to linepipe by field welding machines shall be reported to GDF SUEZ prior to repair in accordance with theline pipe specification.

6.2.7 Bevels and the pipe's external surface within 50 mm of the bevel shall be cleaned by power tools to abright finish prior to lining up the pipe.

6.3 ALIGNMENT6.3.1 Internal line-up clamps shall be used when possible and shall not be removed until 100% of the root

run and hot pass are completed. When external line-up clamps are used the equipment shall besubject to review by GDF SUEZ prior to welding.

6.3.2 For the welding of fittings and flanges the line-up procedure shall be provided for GDF SUEZ review.6.3.3 Welding shall be continuous as far as possible and no joint shall be accepted when subjected to

interruptions not covered by the Welding Procedure Qualification. Strong-backs shall not be used.6.3.4 Hammering or heating shall not be used for correction of misalignment. Spacer tools shall be used to

check final fit-up.


6.3.5 The alignment of abutting pipe ends shall be such as to minimise the internal offset betweensurfaces. Any offset greater than 1.5 mm, provided it is carried by dimensional variations within thespecified permitted tolerances (see Table 10), shall be equally distributed around the circumferenceof the pipe or fittings.

Table 10: Permitted misalignment of surfaces (EN 12732:2000 Table G1)Wall Thickness (T) Permissible

external misalignmentPermissible

internal misalignmentT 10 mm 0.3 x T 1 mm on entire circumference

10mm < T 25.4 mm 20% of T or 3 mm whicheveris less

10% of T or 2 mm whicheveris less

6.3.6 Any misalignment shall be reduced to a minimum by rotation of the pipes to obtain the best fit. Whena pipe with a longitudinal weld is used, the seams on adjacent pipes shall be spaced a minimum of30 apart and preferably in the 10 to 2 o'clock position.

6.3.7 The minimum distance between two circumferential welds shall be 3 times the pipe diameter orminimum 500 mm, whichever is greatest.

6.4 WEATHER PROTECTION6.4.1 Welding shall not be performed when the weather conditions and/or lack of weather protection do

not permit satisfactory workmanship or adequate inspections.6.4.2 Shelters/tents shall be provided/used giving adequate protection, from wind, rain, draft and cold, to

the area of welding.

6.5 TACK WELDS6.5.1 The works shall be set-up, properly spaced and supported and tack welded in accordance with the

welding procedure that is to be employed for the root run. Where preheat is required for the root run,this shall be applied prior to tack welding and maintained until the joint is completed.

6.5.2 Tack welds shall be a minimum of 25 mm long and spaced evenly around the joint circumference.6.5.3 Tack welds may be incorporated into the final joint provided they are ground to a suitable feather

edge at each end to ensure adequate fusion with the root run.6.5.4 Tack welding shall only be carried out by qualified welders.

6.6 STRAY ARCS6.6.1 Arcs shall only be struck on fusion faces. Precautions shall be taken to prevent stray arcs, especially

on the pipe where the earth clamp is fitted.6.6.2 Positions where stray arcs have accidentally occurred shall be repaired. Repairs shall be carried out

to an agreed procedure. The procedure shall include the removal of defective material by grinding,checking by Magnetic Particle examination for cracks and checking that wall thickness is withinpermitted tolerances.

6.7 INTER-RUN CLEANING6.7.1 Each run of weld metal shall be cleaned of slag and flux deposits by either hand or power tools

before the next run is applied, as required.6.8 PREHEAT AND INTERPASS TEMPERATURE6.8.1 The minimum required preheat temperature shall be 100C.


6.8.2 At no time shall the pre-heat exceed that of the qualified welding procedure by more than 50 Cexcept where required in 6.8.3

6.8.3 For welding of flanges to pipe the pre-heat shall be increased to a temperature 50 C higher than thequalified pipe to pipe W.P.Q.

6.8.4 The interpass temperature shall never exceed the maximum temperature specified in the qualifiedwelding procedure, and at no time shall the temperature become high enough to damage the pipe'sprotective coating. The interpass temperature measured immediately before the start of thesubsequent weld run shall not be less than the minimum preheat temperature. In principal, anddependant on material selection, the maximum allowable interpass temperature is 250C.

6.8.5 Preheat shall be applied using electrical or gas methods such that the required temperature is evenlydistributed around the entire circumference of the joint and extending at least 75 mm on either sideof the joint area.

6.8.6 Preheat temperatures shall be checked using thermal indicating crayons, digital thermometers,thermocouples or contact pyrometers.

6.8.7 Preheat temperatures shall be measured approximately 75mm from both sides of the weld / bevel,around the pipes circumference. Interpass temperature shall be measured adjacent to the weld.

6.8.8 Preheat for repair welds shall be applied uniformly around the whole circumferential weld.6.8.9 Maximum interpass temperature shall be monitored on a regular basis to ensure adherence to the

project specific approved WPS. If interpass temperature is seen to be exceeded the regularity ofmonitoring shall be increased so as to satisfy GDF SUEZ that the specified parameters are being met.

6.9 PARTIALLY COMPLETED WELDS6.9.1 Whenever possible, joints shall not be left partially completed. The welding of fittings shall be

completed in one cycle.6.9.2 When production conditions are such that pipe to pipe joints have to be left partially completed the

following conditions shall apply:a) The minimum number of runs deposited before cooling shall be as qualified in the approved

welding procedure.b) When vertical-down welding is used, the second run (hot pass) shall be deposited immediately

after completion of the root run (stringer bead), and the time lapse shall not be greater than thatused in the procedure qualification test, with a maximum of 15 minutes.

c) Upon discontinuation of welding the joint shall be wrapped in dry insulation, heat resistantmaterial with a waterproof backing and shall be cooled in a slow and uniform manner.

d) Prior to recommencement of welding the joint shall be reheated to within the specifiedpreheat/interpass temperature range.

e) No welds shall be left partially completed overnight.

6.10 POST-WELD HEAT TREATMENTNot required unless by the approved WPQ.

6.11 MATERIAL TRACEABILITY AND WELD IDENTIFICATION6.11.1 CONTRACTOR shall employ a procedure for material traceability and weld identification (See also the

requirements of section 10.3). Welders foreman shall track welders performance and identifyproblems regarding individual welders. GDF SUEZ shall be advised of specific problems.

6.11.2 Identification marks adjacent to welds shall be by crayon, weather proof chalk or by some otherappropriate means. The use of hard stamps is not permitted. Identification marks shall not beremoved until after the welds have been visually and non-destructively inspected.


6.11.3 CONTRACTOR's material traceability and weld identification procedure shall be submitted to GDFSUEZ for approval prior to commencement of work.

6.12 PRODUCTION WELD TESTS6.12.1 When specified in the Scope of Work, CONTRACTOR shall allow for and carry out Production Weld

Tests (PWT) as detailed in EN 12732, GDF SUEZ may request, at any time, a weld to be removed bycutting the pipeline, leaving sufficient material on both sides of the weld to accommodate therequired mechanical testing. CONTRACTOR shall re-join and re-weld the pipeline.

6.12.2 The removed weld shall be mechanically tested as required for WPQ test welds (see section 4.)6.12.3 If the weld fails to meet the minimum specified requirements, detailed in section 4., all production

welds produced before the date of testing shall be regarded as not meeting specificationrequirements and are subsequently rejected until CONTRACTOR can demonstrate, to the satisfactionof GDF SUEZ and the CERTIFYING AUTHORITY, that all production welds do have the minimumrequired mechanical properties.


7. REPAIR WELDING7.1 GENERAL7.1.1 CONTRACTOR shall notify GDF SUEZ of CONTRACTOR's intention to repair a weld before commencing

the repair. Weld repairs are permitted for defects located in the filling and cover passes (i.e. partialpenetration repairs) and shall be at least 50 mm long. Repairs at root or including the root shall beminimized and such repairs shall be subject to special approval of GDF SUEZ on a case to case basis.

7.1.2 Only one attempt at a weld root repair shall be performed. If it is still unacceptable, the entire weldmust be replaced. Should the weld be removed (cut-out) the re-bevelling, by machining, shall be suchthat the entire prior heat affected zone is removed.

7.1.3 Weld repairs shall only be carried out by qualified welders working to written, qualified and GDF SUEZapproved procedures.

7.1.4 Only one attempt at any repair in the weld body shall be allowed unless express GDF SUEZ andCERTIFYING AUTHORITY approval is given to attempt a second repair. Should this second repair alsobe un-acceptable according to the Acceptance Criteria agreed for the project, the complete weld shallbe removed.

7.1.5 Repairs shall be limited to a maximum of 20% of the weld circumference (EN 12732:2000 Section6.7). If more than 20% of the weld exhibits defects requiring repair, or if several defective weldsections amount to this length overall, the weld joint in question shall be cut out and re-weldedunless otherwise agreed by GDF SUEZ.

7.2 DEFECT REMOVAL7.2.1 Weld defects shall be removed by grinding, machining or air-arc gouging (followed by grinding).7.2.2 If air-arc gouging is used then the defect area shall be subsequently cleaned by grinding and wire

brushing to a bright metal finish to remove all contaminated material. The cut-out portion shall besufficiently deep and long to remove the defect. At the ends and side of the cut there shall be agradual taper from the base of the cut to the surface of the weld metal. The width and profile of thecut shall be such that adequate access for re-welding is provided. The excavation shall be cleared bymagnetic particle inspection prior to re-welding to ensure complete removal of the defect.

7.2.3 In the event that the defect is close to the weld root and the whole thickness of the weld seam is tobe removed, the new gap opening at the weld root shall remain within the qualified root gaptolerances defined in the WPS. Gouging is only allowed up to 3mm from the internal surface of thepipe after which grinding shall be used to remove the remaining area.

7.2.4 Welds found with cracks shall be repaired by complete removal of the weld i.e. by cutting out asection of pipe containing the weld.

7.2.5 External defects such as undercuts and pin-holes shall be repaired by re-capping the weld for aminimum distance of 38 mm past both ends of the defect. This distance shall be measured parallelto the length of the weld. The re-capped area shall be dressed to a smooth profile. Re-capping shallonly be permitted if the maximum hardness has been shown to be within the acceptance limits ofthis Specification by previous qualification or in-situ portable hardness testing. The in-situ testingprocedure and equipment shall be subject to GDF SUEZ's review and shall be calibrated andcertified.

7.3 INSPECTION OF WELD REPAIRSEach repair weld shall be subjected, as a minimum, to the same inspection and documentationrequirements as the original weld.


7.4 RECORD OF WELD REPAIRA full record of all repairs shall be maintained by CONTRACTOR. The record shall include thefollowing: Weld number Type and size of defect Circumferential location (defined to an approved system) Estimate of the depth (assessed by ultrasonic test where possible) Where possible, the name of the welder who produced the defect Repair welding procedure number Name of repair welder Copy of the inspection reports for the repair Date of repair.

7.5 WELD REPAIR RATEIf the weld repair rate during production reaches a level that is unacceptable to GDF SUEZ (above 5%of weld numbers but taking into consideration initial welding during start-up) and there appears to bea consistent re-occurrence of a specific defect, CONTRACTOR should halt production and carry out aninvestigation into the cause. CONTRACTOR shall inform GDF SUEZ of any reasons for high repair ratesand issue his proposals to alleviate such problems. Any such proposed changes must be within theessential variable range already qualified. If this is not the case a re-assessment shall be maderelating to the suitability and continued acceptability of the qualified welding procedure(s).If the cause of repairs is traced to lack of good workmanship, GDF SUEZ may request the removal ofthe responsible welder(s) from the production line.


8. INSPECTION AND TESTING OF PRODUCTION WELDS8.1 VISUAL INSPECTION8.1.1 CONTRACTOR shall visually inspect every weld to a GDF SUEZ approved procedure and for

compliance with EN12732. All visual inspection shall be documented by CONTRACTOR.8.1.2 Visual inspection shall be carried out at all stages of fabrication and shall include:

a) inspection of weld preparations and set-up prior to start of welding;b) after tack-up (where applicable)c) completed weld.

8.2 NON-DESTRUCTIVE TESTING8.2.1 All welds and repaired welds shall be non-destructively tested (NDT) in accordance with NEN 3650-

2:2003, EN 12732:2000 and EN 288-9:1999 and as required by this specification. NDT shall becarried out according to written procedures, which shall be submitted to GDF SUEZ for approval priorto the commencement of work.

8.2.2 All NDT procedures shall be approved by CONTRACTORs Level 3 specialist.8.2.3 In principal all production girth welds shall be inspected 100% by an automatic ultrasonic system

(AUT) as outlined in Section 11, supplemented where appropriate by other inspection methods.Other welds such as flange welds may be inspected by radiography (see Section 9) subject to GDFSUEZ approval.

8.2.4 In specific cases GDF SUEZ may agree to the application of (X-) radiography (see Section 9) tomainline production welds.

8.2.5 Magnetic Particle Inspection shall be carried out on;a) welds with suspected defects in the root area, when accessible;b) welds in which defects have been detected by radiography, UT or AUT and where additional

inspection is necessary to confirm removal of the defects.Both wet and dry methods may be used, depending on the temperature of the object to be examined.The wet method based on water or oil shall be used when the temperature is below 50C and the drymethod is applicable above temperatures of 50C.

8.3 ACCEPTANCE CRITERIA NDT8.3.1 For the Acceptance Criteria of NDT refer to Section 13 of this Specification.


9. RADIOGRAPHY9.1 RADIOGRAPHIC PROCEDURES9.1.1 Prior to the start of production radiography CONTRACTOR shall provide to the GDF SUEZ a detailed

Radiographic Procedure in compliance with EN 1435:1997, EN 12732:2000 and this specification.As a minimum the procedure shall include the following:a) Project name and job numberb) Procedure number and revisionc) Techniqued) type of equipment and kilo Volt (kV) ratinge) type of filmf) intensifying screensg) shieldingh) source sizei) geometric relationship defined by sketchj) limit of film coveragek) tube voltage or source strength and exposure timel) material thickness rangem) type of image quality indicatorn) processing

9.1.2 The radiation source shall be x-ray unless otherwise agreed by GDF SUEZ. The single wall, singleimage technique shall always be used, unless otherwise agreed with GDF SUEZ.

9.1.3 Wire type image quality indicators, in accordance with EN 462-1 shall be used.9.1.4 Film type and screens shall comply with the requirements of EN 1435:1997. For Weld Procedure

Qualification only very fine grain (Agfa D4 or equivalent) film with lead screens should be used.

9.2 PROCEDURE RADIOGRAPHS9.2.1 Three radiographs shall be taken to qualify each radiographic procedure qualification test, prior to

use on production or qualification welds. These radiographs shall establish the minimumradiographic quality level for all production radiography. Subject to GDF SUEZ agreement, theadequate quality of these radiographs shall result in qualification of the radiographic procedure.Should any variables in the procedure specification change, the radiographic procedure shall be re-qualified. Fogging shall be reported, see 9.8.2.

9.2.2 For procedure qualification Image Quality Indicators shall be placed on both the source side and thefilm side of the weld. Minimum IQI sensitivity shall be as stated in EN1435:1997.

9.2.3 A Radiographic Qualification Technique Sheet shall be produced showing all required and achievedvalues. This must be approved by GDF SUEZ prior to commencement of any production activities.This may be qualified on WPQ material but nipples must not be sent for mechanical testing prior toapproval of the technique(s).

9.2.4 One of the radiographic procedure qualification films shall be available in the production linedarkroom along with the approved technique sheet, for reference purposes, to prove that productionradiographs are being produced to the same quality as that qualified.

9.3 PRODUCTION RADIOGRAPHY9.3..1 Production Radiography (if agreed) shall be carried out on completion of welding and in accordance

with the qualified radiographic procedure.9.3.2 Facilities and viewing conditions shall be in accordance with ISO 25580. Radiographs shall be

viewed dry.9.3.3 Where possible, the IQI shall be placed on the source side of the weld being examined. Where this is

not possible, film side IQI may be used and marked as F.


9.3.4 Film density shall lie in the range 2.0 - 3.6 in the weld area. The density measurement shall be madein the area of the weld image. A minimum of 5cm overlap shall be required to prove coverage of thediagnostic film length. CONTRACTOR shall have a calibrated densitometer available for GDF SUEZuse in the event of disputes.

9.3.5 A continuous number tape shall be used and lead letters shall be affixed to each section of the weldbeing Radiographed. The images of these letters shall appear on the Radiograph to ensureunequivocal identification of the section.

9.3.6 The zero data shall be at the top of the pipe and the direction in which the film numbering systemhas been applied shall be defined alongside the weld using weather proof paint, chalk, crayon or feltpen. The zero data and numbering direction for both Double Joint and Firing Line welds shall be inthe same direction.

9.3.7 To determine the absence of backscatter a letter "B" shall be affixed to the unexposed side of thefilm.

9.3.8 Films of weld repairs shall be marked with the original number with the suffix R. The completecircumference of the weld shall be examined.

9.4 RADIATION PROTECTIONCONTRACTOR shall be responsible for the protection and monitoring of Radiographic personnel andshall ensure that all work is performed in accordance with the relevant Health and Safety Regulationsand in accordanc

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