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2 COMMITTEE ME-038 DR Draft for Public Comment Australian Standard LIABLE TO ALTERATION DO NOT USE AS A STANDARD BEGINNING DATE FOR COMMENT: CLOSING DATE FOR COMMENT: 7 September November 2001 Pipelines Gas and liquid petroleum Part 2: Welding (Revision of AS ) COPYRIGHT PRICE CODE: D

3 Draft for Public Comment Australian Standard The committee responsible for the issue of this draft comprised representatives of organizations interested in the subject matter of the proposed Standard. These organizations are listed on the inside back cover. Comments are invited on the technical content, wording and general arrangement of the draft. Please use the comments pages, provided behind this notice, for your comments. Comments should preferably be typewritten. Please do not return marked-up drafts as comments. When completing the comments page ensure that the number of this draft, your name and organization (if applicable) is recorded. Please place relevant clause numbers beside each comment. Editorial matters (i.e. spelling, punctuation, grammar etc.) will be corrected before final publication. The coordination of the requirements of this draft with those of any related Standards is of particular importance and you are invited to point out any areas where this may be necessary. Please provide supporting reasons and suggested wording for each comment. Where you consider that specific content is too simplistic, too complex or too detailed please provide an alternative. Comments can be sent by post, fax, or on a disk (3½ IBM PC format) marked to the attention of the officer indicated on the top left corner of the form. If the draft is acceptable without change, an acknowledgment to this effect would be appreciated. Normally no acknowledgment of comment is sent. All comments received by the due date will be put before the relevant drafting committee. Where appropriate, changes will be incorporated before the Standard is formally approved. If you know of other persons or organizations that may wish to comment on this draft Standard, could you please advise them of its availability. Further copies of the draft are available from the Customer Service Centre listed below and from our website at STANDARDS AUSTRALIA Customer Service Centre Telephone: Facsimile: sales@standards.com.au Internet:

4 TO: RECOMMENDED CHANGES TO DRAFT AUSTRALIAN STANDARD KOLTA N Standards Australia GPO Box 5420 SYDNEY NSW 2001 FAX NO: (02) nabil.kolta@standards.com.au From (Name and Address) DR Committee: ME-038 Closing 9 November 2001 Date of Comment Title: Pipelines Gas and liquid petroleum Part 2: Welding (Revision of AS ) 1 GENERAL COMMENT (Attach if space insufficient, please type) 2 SPECIFIC COMMENT (please type) Clause/ Figure/ Table Page No Paragraph Line No Recommended Changes and Reason (Exact wording of recommended changes should be given)

5 Clause/ Figure/ Table Page No Paragraph Line No Recommended Changes and Reason (Exact wording of recommended changes should be given)

6 DRAFT FOR COMMENT STANDARDS AUSTRALIA Committee ME-038 Petroleum Pipelines Subcommittee ME Pipeline Welding DRAFT Australian Standard Pipelines Gas and liquid petroleum Part 2: Welding (Revision of AS ) (To be AS 2885) This draft was prepared by Subcommittee ME on behalf or Committee ME-038 to supersede AS Comment on the draft is invited from persons and organizations concerned with this subject. It would be appreciated if those submitting comment would follow the guidelines given on the inside front cover. Attention is drawn to the fact that this document is a draft Australian Standard only and is liable to alteration in the light of comment received. It is not to be regarded as an Australian Standard until finally issued as such by Standards Australia.

7 2 PREFACE This Standard was prepared by the Joint Standards Australia/Standards New Zealand Committee ME-038 to supersede AS The 1995 edition was created in order to supersede and radically revise Section 7, Welding of AS This new revision of the Standard contains numerous technical and editorial changes which became necessary as a result of experience in the use of the Standard in the five years since it was issued. At the same time, the opportunity has also been taken to incorporate the outcomes of an extensive program of pipeline welding research which has been undertaken by the Cooperative Research Centre for Welded Structures with the assistance of industry sponsorship. The most important changes which have been made include the following: The use of automatic welding equipment has been directly provided for, and because of this reference to operators has been included as well as to welders. A list of items requiring approval within the meaning of that term in the AS 2885 Standards has been incorporated in Appendix G. (c) (d) (e) (f) (g) (h) (i) (j) A formal process for any delegation of the operating authority s powers and responsibilities has been included. The application of the Standard to pipelines and pipeline assemblies but not to station pipe-work has been made clear. In recognition of the widely held view in the pipeline industry that the ordinary Standards for the higher grades of gas metal arc welding wires and cellulosic electrodes are not adequate, new appendices have been included to give guidance upon the proper selection of these consumables. Substantive change has been made to the requirements dealing with qualification of a welding procedure. The statement of the purpose has been improved, and a requirement has been introduced for the procedure to be free from the risk of hydrogen assisted cold cracking (HACC), ie for HACC to be designed-out of the procedure. A new Appendix F has been incorporated to give guidance upon how this can be achieved. Two serious problems that the industry has faced for many years have been addressed in changes to the methods of qualifying a welding procedure. The need for repeated and unnecessary requalification by testing of simple proven procedures has been largely eliminated. In addition to the pre-existing provision that procedures could be qualified by the production of documentary evidence of previous approval, a new provision has been introduced in which procedures applying to the most common grades and thicknesses in low risk applications are deemed to be prequalified, and therefore do not require testing. As well as this, in special circumstances, in order to address the problem of qualifying procedures on large or expensive fittings and in other circumstances where it may be impracticable or impossible to obtain representative material upon which to qualify the procedure, a provision has been introduced making it possible for qualification by the use of appropriately qualified and experienced supervision. The essential variables have been revised and clarified. Specific reference has been included to the outcome of the CRC-WS research showing, for normal lifts, the small effect upon the risk of HACC of the release of the line-up clamp prior to completion of the root pass. The related subjects of excessive weld reinforcement height and inadequate radiographic density in the weld region has been given attention as a result of the 1102-PDR.DOC(2410.CDR) 03/09/01

8 (k) (l) (m) 3 failure of the treatment in the 1995 revision to work adequately in practice. More attention is given to the problem of excessive reinforcement height at the welder qualification stage and at the stage of visual inspection of production welds. Following that, although the radiographic density requirements have been changed and are now primarily couched in terms of parent metal density, there is now a mandatory minimum lower density limit of 1.3, and if this is not met, the weld must be ground to reduce the reinforcement height and then be re-radiographed. Previously it was seen as the radiographer s responsibility to achieve recommended density limits. The changes reflect the fact that that alterations to the radiographic procedure in order to bring the density above the minimum limit in excessively thick regions, whilst being maintained below the maximum permitted values in the parent metal, would adversely affect radiographic quality. The ultrasonic inspection requirements have been completely revised. Ultrasonic inspection is now a permitted method of inspection of equal status to radiography. Previously the use of ultrasonic testing required approval. The use of automatic ultrasonic inspection is now expressly provided for. The amount and the location of non-destructive examination is required to be considered as part of the risk assessment conducted in accordance with AS The Tier 1 and 2 defect acceptance criteria have been revised to reflect the findings of the research program. This is not an exhaustive list of changes. The term normative has been used in this Standard to define the application of the appendix to which it applies. A normative appendix is an integral part of a Standard. The term informative has been used in this Standard to define the application of the appendix to which is applies. An informative appendix is only for information and guidance PDR.DOC(2410.CDR) 03/09/01

9 4 CONTENTS Page 1 SCOPE AND GENERAL MATERIALS POST-WELD HEAT TREATMENT WELDING POSITIONS QUALIFICATION OF A WELDING PROCEDURE ASSESSMENT OF A TEST WELD TO QUALIFY A WELDING PROCEDURE QUALIFICATION OF A WELDER OR OPERATOR ASSESSMENT OF TEST WELDS FOR WELDER OR OPERATOR... QUALIFICATION WELDER OR OPERATOR QUALIFICATION AND DISQUALIFICATION DESIGN OF A WELDED JOINT PRODUCTION WELDS WELDING ON A PIPELINE AFTER COMMISSIONING OR AFTER HYDROSTATIC TEST WELDING ONTO AN IN-SERVICE PIPELINE ASSESSMENT OF PRODUCTION WELDS AND REPAIR WELDS VISUAL EXAMINATION NON-DESTRUCTIVE EXAMINATION RADIOGRAPHIC EXAMINATION QUALIFYING A RADIOGRAPHIC PROCEDURE ULTRASONIC EXAMINATION MAGNETIC PARTICLE TESTING DYE-PENETRANT TESTING CRITERIA OF ACCEPTANCE FOR GIRTH WELD DISCONTINUITIES REPAIR OF AN UNACCEPTABLE WELD REMOVAL OF AN ARC BURN CUTTING OUT AN UNACCEPTABLE WELD OR AN ARC BURN RECORDS...87 APPENDICES A LIST OF REFERENCED DOCUMENTS...92 B WELD PROCEDURE DETAIL FORM...95 C TEST WELD RECORD FORM...96 D GUIDANCE ON ` GMAW WELDING CONSUMABLES FOR MECHANIZED PIPELINE GIRTH WELDS...99 E SELECTION AND SPECIFICATION OF CELLULOSIC WELDING ELECTRODES F AVOIDANCE OF HYDROGEN ASSISTED COLD CRACKING (HACC) G LIST OF ITEMS REQUIRING APPROVAL PDR.DOC(2410.CDR) 03/09/01

10 5 STANDARDS AUSTRALIA Australian Standard Pipelines Gas and liquid petroleum Part 2: Welding 1 SCOPE AND GENERAL 1.1 Scope This Standard specifies materials, welding consumables, welding processes, weld preparations, qualifications of welding procedures and personnel, and fabrication and inspection requirements for the construction and maintenance welding of pipelines down to 3.2 mm wall thickness designed and constructed in accordance with AS The welding of pipelines with wall thicknesses less than 3.2 mm is not precluded but is not expressly covered by this standard. The welding of such pipelines shall be given special consideration. The welding may be done by a manual metal arc, submerged arc, gas tungsten arc, gas metal arc, flux cored arc, oxyacetylene, or by a combination of these using a manual, semiautomatic, or automatic welding technique or a combination of these techniques. The welds may be produced by a position or roll welding or by a combination of position and roll welding. 1.2 Qualification and approval Welding shall be performed in accordance with qualified welding procedures by qualified welders or operators. Welding procedures shall be approved. The Welding procedure shall be documented. The list of Items requiring approval in accordance with this Standard, is given in Appendix G. Activities undertaken within the scope of this Standard shall be directed by an operating authority appointed for the purpose of giving approvals as defined in this Standard. The process for any delegation of the operating authority s powers shall be in accordance with Figure 1.2.

11 6 NOTES: FIGURE 1.2 APPROVAL PROCESS 1 The use of ISO 3834 is recommended when the authority to approve is delegated. 2 The audit shall be conducted on behalf of the operating authority. It may be conducted by a third party. The audit shall address the items listed in Appendix G. 1.3 Application This Standard is applicable to the welding of joints in or on pipelines, and pipeline assemblies. It is not intended that this Standard be applied to the following: Station pipework as defined in AS Longitudinal welds or spiral welds made during the manufacture of a pipe. (c) Welds made by the manufacturer during fabrication of a component (see Clause for the definition of a component). (d) (e) Underwater welding. Hyperbaric welding. Also, it is not intended that this Standard be applied retrospectively to existing installations. It is intended that welding procedures complying with and welders who are qualified in accordance with the appropriate previous editions of this Standard may continue to be used for the maintenance of existing installations. New welding procedures and new welding qualifications shall be qualified in accordance with this Standard.

12 1.4 Referenced documents 7 A list of the documents referred to in this Standard is given in Appendix A. 1.5 Definitions For the purpose of this Standard, the definitions given below apply Accessory A component of a pipeline other than a pipe, valve, or fitting, but including a relief device, a pressure-containing item, hanger, support, and all other items necessary to make a pipeline operative whether or not such items are specified by the Standard Approved and approval Approved by the operating authority and includes obtaining the approval of the relevant statutory authority where this is legally required. NOTE: Approval requires a conscious act and is given in writing Burn-off rate The ratio of length of electrode consumed to the length of weld pass deposited. Burn-off rate is proportional to the heat input, divided by the square of the electrode core wire diameter. NOTE: WTIA Technical Note 1 provides information relating burn-off rate to heat input Component Any part of a pipeline other than the pipe Construction All activities required to fabricate, construct and test a pipeline, and to restore the right of way Defect A discontinuity or imperfection of sufficient magnitude to warrant rejection on the basis of the requirements of this Standard Design temperatures The range of the metal temperatures to be expected in construction, testing, and normal operation Diameter The outside diameter nominated in the material order ignoring the manufacturing tolerance provided in the specification under which the pipe was manufactured Discontinuity A generic term for material imperfections (see Clause ), which includes defects (see Clause 1.5.6) and non-rejectable irregularities Engineering critical assessment (ECA) A formal process for the assessment of structures containing discontinuities in order to determine whether the structure is fit for purpose. NOTE: The process involves the use of fracture mechanics and requires consideration of the discontinuity, the stress, and the material properties for the likelihood of failure arising from fracture, plastic collapse, fatigue, buckling, creep, corrosion/erosion, and leakage Engineering design The detailed design of a pipeline system, developed from process and mechanical requirements, complying with the requirements of this Standard and including all necessary specifications, drawings, and supporting documents.

13 Environment 8 The complex of climatic, demographical, geotechnical, oceanographic, and biotic factors that act on a pipeline influencing the design, construction, testing, inspection, operation, and maintenance Essential variable Variable in which a change outside specified limits requires requalification of welding procedure or welder or operator qualification Fitting A component, including any associated flanges, bolts, and gaskets used to join pipes, to change the direction or diameter of a pipeline, to provide a branch, or to terminate a pipeline Fluid Any vapour, liquid, gas, or mixture thereof Gas Any hydrocarbon gas or mixture of gases, possibly in combination with liquid petroleum condensates or water Heat input (arc energy) where Q = EI V Q = welding energy input, in kilojoules per millimetre E = arc voltage, in volts (RMS value for a.c.) I = welding current, in amperes (RMS value for a.c.) V = welding speed, in millimetres per minute. NOTE: Both the arc voltage and welding current are to be measured accurately with voltage measured between the electrode holder or contact tube and the work piece earth clamp Hot repair Repair welding on a pipeline containing hydrocarbon gas under controlled conditions with a burning gaseous atmosphere present due to escape of the pipeline contents Hot tap A connection made to a pipeline containing hydrocarbon fluid Hydrogen assisted cold cracking (HACC) Hydrogen cracking is a form of brittle cracking which occurs at near ambient temperature in the weld or heat-affected zone of ferritic steel weldments, due to the combined effects of hydrogen arising from welding, together with tensile stress and a susceptible microstructure Imperfection A material discontinuity or irregularity that is detectable by inspection in accordance with this Standard Inert gas Shielding gas consisting principally of argon, helium, or a mixture of the two In-service welding Welding onto a pressurized product filled pipeline.

14 Inspector 9 A person appointed by the operating authority to carry out inspections required by this Standard Location class An area classified according to its general geographic and demographic characteristics Mainline pipework Those parts of a pipeline between stations, including pipeline assemblies Matching (Undermatching) Refers to the ability of a full scale welded joint containing discontinuities at the limit of the acceptance criteria to match the strength of the pipe and to ensure that under displacement controlled loading that plastic strains occur in one or both of the pipes before the weld breaks (See Appendix E) Matching ratio Ratio of the transverse yield stress of the weld metal and the axial yield stress of the pipe. (see Clause 6.4.9). This ratio can be used as an indicator of weld strength matching (see Clauses and (c) and (d)) May Indicates the existence of an option Natural gas Gaseous hydrocarbons (mainly methane) from underground deposits, the production of which may be associated with the production of crude petroleum. The gas is described as ' wet' or ' dry' according to the proportion of readily condensable hydrocarbons which it contains. This term also applies to the purified product. NOTE: This definition is that given in ISO 1998/ Nominal thickness The thickness nominated in the material order, ignoring the manufacturing tolerance provided in the specification under which the pipe was manufactured. (Quantity symbol: δn.) Non-planar discontinuity Weld discontinuities not included in the planar category, including volumetric discontinuities such as porosity, root concavity, burn through, hollow bead, and slag inclusions Operating authority The organization responsible for the design, construction, testing, inspection, operation and maintenance of facilities within the scope of the Standard Operator A person who operates automatic welding equipment Pig A device that is propelled inside a pipeline by applied pressure. NOTE: Pigs can be of various types, such as a gauging pig for checking a pipeline bore, a swabbing pig for cleaning a pipeline, or an intelligent pig for checking wall thickness, deformation or cracking, or the integrity of the coating of a pipeline.

15 Pig trap (scraper trap) 10 A fabricated component to enable a pig to be inserted into or removed from an operating pipeline Pipeline assemblies Assemblies of pipe, valves and fittings which are considered to be integral parts of the pipeline. (See AS ). Such assemblies are usually pre-fabricated off site Planar defect A category of weld discontinuities which are assumed to have only two dimensions and which, for structural purposes, are considered to be equivalent in behaviour to a crack. Discontinuities which fall into this category for the purposes of this Standard are (c) undercut deeper than the permitted limits; all inadequate penetration and lack of fusion defects; and cracks other than crater cracks Preheat temperature The temperature immediately prior to the commencement of welding resulting from the heating of the parent metal in the region of the weld. NOTE: Normally, a minimum preheat temperature may be required, for example, to avoid hydrogen cracking in the weld metal or heat-affected zone. A maximum value may also be specified in order to achieve particular levels of toughness and/or strength. It is recommended that preheat should be measured at least 75 mm from the weld line Pre-tested pipe A pipe or a pressure-containing component that has been subjected to a pressure test in accordance with this Standard before being installed in a pipeline and intended to be used for tie-in or maintenance purposes Shall Indicates that a statement is mandatory Should Indicates a recommendation Sour service Piping conveying crude oil or a natural gas containing hydrogen sulfide and an aqueous liquid phase in a concentration that may affect materials. The limits defined in NACE MR0175 are deemed for the purposes of this Standard to constitute sour service Thickness for design internal pressure The thickness of material, calculated according to the equations in the design section of this Standard, required for the material to be capable of withstanding the design internal pressure. (Quantity symbol: δdp.) Weld metal deposition repair Repair method for loss of thickness, e.g. corrosion defects by surfacing with deposited weld metal whilst the pipeline is in service Weldability The ability of a metal to be welded under given fabrication conditions in a specific weldment, and to perform satisfactorily in service.

16 Yield strength either 11 the specified minimum yield strength (SMYS) to which the pipe is purchased; or the actual yield strength (AYS) being the hoop stress determined from the pressure at the strength test end point as specified in this Standard. NOTE: The yield strength may be represented by a material grade, e.g; X60 (Yield strength 413 MPa). 1.6 Rounding of numbers An observed or calculated value shall be rounded to the nearest unit in accordance with AS 2706, and for the purpose of assessing compliance with this Standard, the specified limiting values herein shall be interpreted in accordance with the ' rounding method' described in AS 2706, i.e. the observed or calculated value shall be rounded to the same number of figures as in the specified limiting value and then compared with the specified limiting value. For example, for specified limiting values of 2.5, 2.50, and 2.500, the observed or calculated value would be rounded respectively to the nearest 0.1, 0.01, or For examples of the interpretation of specified values in accordance with the rounding method, see AS MATERIALS 2.1 General The requirements of this Clause are applicable to the welding of materials which comply with AS Consumables Electrodes for manual metal-arc welding Welding electrodes for manual metal-arc welding shall comply with one of the Standards listed in Table Additionally lower strength electrodes (see welding process column in Table 2.2.1) should be used for welding of all passes for pipe and components in material up to and including grade X60; unless it can be shown it is difficult to meet the required mechanical properties (see Clause (c)), lower strength electrodes should be used for the first pass, when welding pipe and components of material greater than grade X60; and (c) should be selected and specified in accordance with Appendix E Wires for automatic welding Wires for automatic welding shall comply with one of the Standards listed in Table 2.2.1, and should be selected, taking account of Appendix D Storage and handling of consumables Consumables shall be stored and handled as follows: Electrodes in accordance with one or more of the following: (i) (ii) Recommendations of the manufacturer. Requirements of the relevant Standard. (iii) Recommendations in WTIA Technical Note 3. Filler rods and fluxes in accordance with one or both of the following:

17 (i) (ii) Recommendations of the manufacturer. Requirements of the relevant Standard. 12

18 13 TABLE WELDING CONSUMABLES Welding process Manual metal-arc welding using lower strength cellulose electrodes Manual metal-arc welding using medium strength cellulose electrodes Manual metal-arc welding using lower strength hydrogen- controlled electrodes Manual metal-arc welding using medium strength hydrogen- controlled electrodes Standard AS/NZS ANSI/AWS A5.1 AS/NZS ANSI/AWS A5.5 AS/NZS ANSI/AWS A5.5 Electrode, wire, rod or weld metal classification E4110, E4111 E6010, E6011 E4810-A1, E4810-G, E4810-P1, E4811-A1, E4811-G, E7010-A1, E7010-G, E7010-P1 E7011-A1, E7011-G E5510-G, E5510-P1, E5511-G, E6210-G, E6211-G, E8010-G, E8010-P1, E8011-G, E9010-G, E9011-G AS/NZS E4115, E4116, E4118, E4815, E4816, E4818, E4846, E4848 ANSI/AWS A5.1 Note 5 AS/NZS ANSI/AWS A5.5 AS/NZS ANSI/AWS A5.5 E7015 HZR, E7016 HZR, E HZR, E7018 HZR, E HZR, E7048 HZR E4815-A1, E4815-G, E4816-A1, E4816-G, E4818-A1, E4818-G E7015-A1, E7015-G, E7016-A1, E7016-G, E7018-A1, E7018-G E5515-G, E5516-G, E5518-G, E6215-G, E6216-G, E6218-G E8015-G, E8016-G, E8018-G, E9015-G, E9016-G, E9018-G Submerged arc welding AS W401, W402, W403, W404, W405, W501, W502, W503, W504, W505 ANSI/AWS A5.17 EL8, EL8K, EL12, EM5K, EM12, EM12K, EM13K, EM15K Flux or gas classification Remarks Cellulose Note 7 Cellulose Note 7 Basic coated Basic coated Fused or bonded Note 1 F60, F61, F62, F70, F71, F72 Gas tungsten-arc welding AS/NZS R1, R2, R3, R4, R5 Shielding gas to be used. Note 2 (continued)

19 14 TABLE (continued) Welding process Standard Electrode, wire, rod or weld metal classification Gas metal-arc welding AS/NZS W401, W402, W403, W404, W405, W501, W502, W503, W504, W505 ANSI/AWS A5.18 E70S-2, E70S-3, E70S-4, E70S-6 Flux or gas classification Remarks Notes 2 & 6 Various Shielding gas to be used. Notes 2 & 6 ANSI/AWS A5.28 ER8DS-D2-1B Various Shielding gas to be used. Notes 2 & 6 Flux cored arc welding AS W401, W402, W403, W404, W405, W501, W502, W503, W504, W505 Flux cored arc welding ANSI/AWS A5.20 E70T-1, E70T-5, E71T-1, E71T-5 Note 3 Various Shielding gas to be used. Note 2 Flux cored arc welding ANSI/AWS A5.20 E71T-GS Note 4 NOTES: 1 Any combination of these electrodes and fluxes may be used to qualify a procedure. Each combination is to be identified by its complete classification number (e.g. F62-EM12K or F71-EL12 as specified in ANSI/AWS A5.17, EL12-FMM-W501 as specified in AS ). 2 Any combination of these electrodes and gases may be used to qualify a procedure. Each combination is to be identified by its complete classification number (e.g. ES2-GC-W501H), and each shielding gas is to be specified by brand name or mix analysis. 3 Any combination of these electrodes (with or without gas) may be used to qualify a procedure. Consumables are to be identified by the complete classification number (e.g. ETP-Nn-W402). Where a shielding gas is used, this shall be specified by brand name or mix analysis. 4 Any combination of these electrodes may be used to qualify a procedure. Consumables are to be identified by the complete classification number (e.g. root pass E71T-GS, other passes E71T8-K2). 5 `Z designates that the electrode meets the requirements of the diffisible hydrogen test with an average value not exceeding `Z ml of H2 per 100 g of deposited metal. 6 See also Appendix D. 7 See also Appendix E. 3 POST-WELD HEAT TREATMENT Components which comply with a nominated Standard normally do not require post-weld heat treatment, but, where determined to be necessary under the provisions of Clause 5, post-weld heat treatment shall be carried out in accordance with AS 1210 or an approved method. 4 WELDING POSITIONS 4.1 Designation Positions for test welds shall be designated as shown in Figure 4.1, and shall be within ±5 of the nominal position. Where the position of a production weld cannot be related to one or more of the designated weld positions, a special test position shall be used.

20 4.2 Limits of qualified positions 15 The position used in the welding procedure qualification test and welder qualification tests shall also qualify other positions as shown in Table 4.2(A). TABLE 4.2(A) POSITIONS FOR WELDING PROCEDURE AND WELDER QUALIFICATION TESTS FOR BUTT, FILLET, SLEEVE AND BRANCH WELDS ON PIPE AND RECIPROCITY OF TYPES OF WELD AND POSITIONS (Note 3) Qualification test on pipe Type of weld and position qualified (See Note 2) Type of weld Position of axis Butt Fillet Branch Sleeve Description Butt (Girth) Symbol Pipe Weld 1G 2G Horizontal rotated Vertical fixed 5G Horizontal fixed 6G 2G and 5G1 (See Note 1) Inclined 45 fixed Vertical fixed, and horizontal fixed Fillet 2F Vertical fixed Branch (See Note 4) 2FR 4F 5F Horizontal rotated Vertical fixed Horizontal fixed Horizontal (flat) Horizontal 1G and 2G 2F and 2FR 1G Multiple 1G and 5G Any Multiple Any Any Horizontal and multiple Any Any Horizontal 2F and 2FR Horizontal 2FR Horizontal (overhead) 2B 315 to 45 Horizontal (flat) 4B 135 to 225 Horizontal (overhead) 2F, 2FR, and 4F Multiple Any 5F (sleeve) 1G and 2G 1G and 2G 2F and 2FR 2F, 2FR, and 4F 2B 2B and 4B 5B 45 to 135 Multiple 1G and 2G Any Any Sleeve 5F Horizontal 1G Plate 2G Plate 4G Plate Fixed Downhand butt plate Horizontal butt plate Overhead butt plate Multiple Any Any Downhand (flat) Any 1G Plate Horizontal Any 1G and 2G Plate Overhead Any Any

21 16 NOTES: 1 Qualified by separate tests for each position or a combination of 2G and 5G test welds. 2 Refer to Figure 4.1 for the types of welds and positions. 3 Table 4.2(B) gives reciprocity of weld types for welder qualification (see also Clause 8.6). 4 Tee butt welds qualify fillet welds as listed. Fillet welds do not qualify tee butt welds. Butt welds qualified by branch connection weld procedure qualification tests shall be restricted to the types of butt welds involved in the branch connection.

22 17 TABLE 4.2(B) RECIPROCITY OF WELD TYPES FOR WELDER QUALIFICATION Weld types qualified in welder qualification test Weld type number qualified without further testing (Note 1) Type number of weld NOTES: Description of weld 1 1G butt weld with pipe horizontal and rotated 2 2G butt weld with pipe vertical and fixed 3 5G butt weld with pipe horizontal and fixed 4 2G and 5G2 butt weld or a 6G butt weld with pipe inclined 4 5 and fixed 5 2G and 5G2 butt weld or 6G butt weld plus mark out, cut, fit and weld a reinforced siton tee-butt branch D/3 in position 5B 6 Mark out, cut, fit and weld a reinforced sit-on tee-butt pipe branch D/3 in position 5B 7 Mark out, cut, fit and weld in position 5B either a sit-on bevelled end forged fitting or a sit-on tee-butt pipe branch 8 Make a fillet weld in position 5F on the socket weld end of a forged fitting, a socketed pipe, a slip-on flange, a bracket, a pad or a plain end sit-on branch 9 Mark out, cut, fit, and weld in position 5B either a forged set-in branch or a non-reinforced set-in pipe branch 10 Fit and weld either a circumferential split sleeve or a tee fitting with a longitudinal single V butt weld with backing strip and ends fillet-welded For reciprocity of welding positions, see Table 4.2(A) (See also Clause 8.6.) 2 Qualified by separate tests in each position or a combination of 2G and 5G test welds.

23 Type of weld 18 Welding positions Butt weld Axis of pipe horizontal Pipe rotated Flat position, 1G Axis of pipe vertical Pipe fixed Horizontal position, 2G Axis of pipe horizontal Pipe fixed Multiple position, 5G Axis of pipe inclined 45 Pipe fixed Mutiple position, 6G Fillet weld Axis of pipe horizontal Pipe rotated Horizontal position, 2FR Axis of pipe vertical Pipe fixed Horizontal position, 2F Axis of pipe horizontal Pipe fixed Multiple position, 5F Axis of pipe vertical Pipe fixed Overhead position, 4F Sleeve/Stoppl e fitting weld Branch weld Axis of pipe horizontal Pipe rotated Multiple posiiton, 5F Circumferential fillet Axis of pipe horizontal Axis of branch normal Pipe and branch fixed Branch weld positioned within 45 to 135 Multiple position, 5B 1G Plate with bakcing Strip Longitudinal weld Axis of pipe horizontal Axis of branch normal Pipe and branch fixed Branch weld positioned within 135 to 225 Overhead position, 4B 2G Plate with backing Strip Longitudinal weld FIGURE 4.1 WELD TEST POSITIONS 5 QUALIFICATION OF A WELDING PROCEDURE 5.1 Purpose of qualifying a welding procedure 4G Plate with backing Strip Longitudinal weld Axis of pipe horizontal Axis of branch normal Pipe and branch fixed Branch weld positioned within 315 to 45 Horizontal position, 2B A welding procedure shall be qualified to demonstrate that the production welds made in accordance with the welding procedure

24 (c) 19 will have the required mechanical properties such as strength, ductility and hardness; will be sound, i.e. free from cracks, unacceptable porosity or other defects, and will be free from the risk of hydrogen assisted cold cracking (HACC). The basis of the design of the welding procedure for the avoidance of HACC shall be documented in the welding procedure specification (see Appendix B). Requirements for the avoidance of HACC are given in Appendix F, and recommended methods for designing out HACC from welding procedures are included in Appendix F. 5.2 Methods of qualification A welding procedure shall be qualified by one of the following means, in accordance with the flow chart shown in Figure 5.2. Regardless of the method of qualification, the welding procedure shall be documented and approved. A suitable form of documentation is given in Appendix B. (c) Qualification by testing Where a welding procedure is to be qualified by testing, a test weld shall be made on a suitable test piece in accordance with the proposed welding procedure, and shall be examined, tested, and assessed in accordance with Clause 6. NOTE:The welding procedure qualification test may also be used to qualify a welder (see Clause 7.3). Where the weld meets all the criteria of acceptance, and the results have been recorded (see Clause 6.5.4), the welding procedure shall be qualified. Qualification by documentation Part or all of the welding procedure qualification tests may be waived on production of approved documentary evidence that similar welds, within the limits of the essential variables, have been made and tested, and that the welding procedure has been qualified previously in accordance with one of the following: (i) This Standard or any of its previous editions. (ii) AS (iii) AS 4041 or AS 1210 through AS (iv) AS (v) ASME B31.3 or B31.8 through ASME IX (vi) API This method of qualification shall apply only to Tier 1 defect acceptance criteria as described in Clause 22. Qualification by prequalification This method of qualification is not applicable to the welding of fittings or welding on live pipelines. A welding procedure may be qualified by being deemed to be prequalified when the following restrictions are met: (i) The joints are butt joints between pipes of equal thickness. (ii) The weld preparation is in accordance with Figure (iii) (iv) The pipe diameter is within the range DN50 to DN500. The pipe thickness is less than 10 mm. (v) The pipe grade does not exceed X60 and the C.E. does not exceed 0.40.

25 20 (vi) The welding process is MMAW using E4110 electrodes in the vertical down direction. (vii) The number of passes is not less than 3. (viii) The time lapse between starting the root pass and starting the hot pass shall not exceed 8 minutes. (ix) The arc energy is not less than 0.5 KJ/mm, or burn-off rate is not less than 1.00 for 3.2 mm electrodes or 0.50 for 4.0 mm electrodes. (x) The preheat is not less than that determined by reference to WTIA TN 1. (xi) The lifting and lowering practice is restricted to normal lifts as defined in Appendix F. NOTE: Extreme lifts may be dealt with within this Clause by adhering to the provisions of Appendix F, paragraph F9.2. (xii) The welds are made by welders qualified in accordance with this Standard. Prequalified welding procedures which are qualified under this Clause are deemed suitable for use by dint of their long satisfactory use and do not require testing in accordance with Clause 5.2 or the production of approved documentation in accordance with Clause 5.2. (d) Qualification by the use of supervision In special circumstances outside the restrictions of Clause 5.2(c), and where qualification by testing or documentation is not practicable, a limited number of special welds may be made by qualified welders working under the direct and continuous supervision of a qualified welding engineer. An example of these special circumstances might be the welding into a pipeline of a large and expensive fitting where it would not be practicable to meet the test weld requirements of this Standard. The welding engineer shall have formal qualifications in welding engineering, and shall be experienced in the welding of pipelines, including specifically in the type of welds that are proposed. The welding procedure used for supervised welds shall be documented and shall be approved. The documentation shall include a statement of the qualifications and experience of the welding engineer who will supervise the welds.

26 21 FIGURE 5.2 WELDING PROCEDURE QUALIFICATION FLOWCHART 5.3 Welding procedure specification Table 5.3(A) lists the items which are to be defined for each welding procedure. Table 5.3(B) lists the essential variables for qualified welding procedures. Weld passes in a butt weld shall be identified as shown in Figure 5.3. NOTE: A welding procedure specification may be presented in any suitable form, written or tabular, which suits the needs of the organization responsible for qualification of the welding procedure. Typical suitable forms for welding procedure detail and test weld record are shown in Appendices B and C. 5.4 Changes in a welding procedure Change in an essential variable The following shall be observed: Where a change beyond the permissible limit in Table 5.3(B) is made to an essential variable in a qualified welding procedure, the welding procedure specification shall be changed, and the new procedure shall be qualified. Changes beyond the limits in Table 5.3(B) may be made without requalification providing that: (i) (ii) The changes are shown by appropriate documentary evidence in the form of an amendment to the qualified welding procedure not to increase the risk of HACC. This evidence shall take into account the guidance material in Appendix F and WTIA Technical Note 1. The change does not involve an increase in carbon equivalent of more than 0.10.

27 (iii) The amended welding procedure specification is approved Change in other than an essential variable 22 Where a change is made to other than an essential variable with the agreement of the operating authority, the welding procedure specification shall be modified but need not be re-qualified Multiple changes other than changes of essential variables Where a number of changes are made to a welding procedure, none of which is a change to an essential variable but all of which acting in concert are likely to be detrimental to the weld, the welding procedure specification shall be changed, and the new procedure shall be qualified. 5.5 Test piece size The size of the test piece(s) used for welding procedure qualification test welds shall be sufficient to provide the required number of test specimens. 5.6 Test piece material Test piece material shall comply with the following: (c) (d) Test piece material used for welding procedure qualification test welds shall be of the same specification, grade or class, outside diameter, and wall thickness as will be used in the major part of the production. For material grades equal to or greater than X70 the test piece material shall be, where possible, from the factory of manufacture, and shall have the same nominal composition as the material represented. Where a weld is to be made between a material grade less than X70 and another with material grade equal to or greater than X70, a welding procedure qualification test weld shall be made for the combination. Material which is in compliance with the same specification, grade, or class but with a higher carbon equivalent shall be deemed to be valid for a parent metal with a lower carbon equivalent. 5.7 Assembly of test pieces Test pieces shall be assembled in the required position so that the weld can be made in accordance with the welding procedure specification. Where tack welds are specified, they shall be made from the side to be welded, and, before the test weld is made, misalignment caused by tack welds shall be corrected. 5.8 Test conditions Subject to the requirements of Appendix F, a test weld shall be made under conditions which simulate the worst case likely to be encountered during construction or operations including, where these are required by Appendix F, the use of full-length suspended pipes, line-up clamps, lowering off, support and environmental conditions. The welding heat input or burn-off rate shall be at or near the lower end of the range qualified. Furthermore, where delay in completing some joints is anticipated, the test weld shall simulate that delay. 5.9 Supervision of test weld A test weld shall be made under continuous supervision to ensure that all the requirements of the welding procedure specification are complied with and that the weld is free from unauthorised repairs.

28 The supervisor shall be qualified in accordance with Clause The test should be terminated at any stage when it becomes apparent to the supervisor that a satisfactory weld cannot be made Identification of the test weld Each qualified welding procedure and each welder or operator shall be assigned an identification. This identification shall be clearly marked on the test piece adjacent to the weld. FIGURE 5.3 IDENTIFICATION OF WELD RUNS IN A SINGLE-SIDED BUTT WELD TABLE 5.3(A) ITEMS FOR QUALIFIED PROCEDURES PIPE Item (see Note 1) Remarks 1 Material specification Pipe and fittings complying with this Standard, another relevant Australian Standard, or another approved Standard Material manufacturer Where material grade X70 (c) Material carbon MN Cr + Mo + V Cu + CE = C equivalent (CE) Diameter group Applicable to the diameter of each pipe and branch pipe 3 Wall thickness Nominal wall thickness PROCESS 4 Welding process The arc welding process (e.g. manual, semi-automatic, automatic, a combination) DESIGN 5 Preparation Pipe end preparation; i.e. type of bevel, size of root face, width of root gap 6 Weld shape and size Shape and size of welds 7 Backing Type of backing ring or consumable insert (if used) 8 Passes Number and sequence of passes (including stripper passes) 9 Position Positions shown in Table 4.2(A) 10 Direction of welding Vertical up or vertical down FILLER 11 Filler metal Size and classification of electrode or welding wire for each pass Ni (continued)

29 24 Item (see Note 1) Remarks SHIELDING 12 Shielding gas Type and composition of gas or gas mixture used for shielding or backing (c) Nozzle or cup size Type and flow rate for shielding or backing gases 13 Shielding flux Type, size, classification, make, and brand number of flux ELECTRICAL 14 Electrical characteristics Arc type, current, polarity and voltage for each size of electrode. The conditions of use for welding consumables shall at all times lie within the manufacturer' s recommended range. PROCEDURE 15 Number of welders Minimum number of root pass welders 16 Removal of line-up clamp, and/or type of lift (see Note 4) Minimum percentage of root pass completed before release of clamp. Where less than 100% the location of the completed proportion shall be specified. (See Notes 5 and 6). The type of lift shall also be specified. 17 Tack welding (if used) Number and size of tacks employed 18 Time lapse between individual passes (see Note 2) 19 Preheat temperature and interpass temperature Maximum time lapse between the start of the root pass and the start of the hot pass; and between subsequent passes Heating method, width heated, preheat temperature and interpass temperature 20 Postweld heat treatment Heating method, width heated, minimum and maximum temperature, time at temperature, method of temperature measurement, and control of maximum and minimum cooling rates 21 Heat input or burn-off rate (see Note 3) CLEANING Heat input or burn-off rate for each pass 22 Cleaning Equipment and method used DEFECT ACCEPTANCE CRITERIA 23 NDE acceptance criteria The tier of acceptance criteria for girth weld discontinuity NOTES: 1 Item indicates the specification topic. 2 The method of defining time lapse shall be the same for production welds as for procedure qualification welds. It is recommended that the time lapse from start of root pass to start of hot pass be the defined method to avoid uncertainties associated with root repairs. 3 Burn-off rate is defined as the ratio of length of electrode consumed to the length of weld pass deposited. WTIA Technical Note 1 provides information relating burn-off rate to heat input. 4 Recent research work carried out by the CRC for Welded Structures (CRC-WS) has shown that for normal lifts (see Appendix F) the additional strains, over and above the weld contraction strains, caused by lifting and lowering are small for pipe diameters less than DN500 It has also shown that providing due attention is paid to the other factors governing the risk of HACC, the removal of the line-up clamp after at least 50% of the root pass is completed, does not by itself cause cracking. 5 The proportion of the root pass which is completed before clamp release shall be 50%. 6 Where the proportion of the root pass which is completed before the line-up clamp is released is <100%, then at lease 80% of both the top and bottom quadrants shall be completed before clamp release.

30 25 TABLE 5.3(B) ESSENTIAL VARIABLES FOR QUALIFIED WELDING PROCEDURES PIPE Item (see Note 1) Remarks 1 Material Change of material grade between <X70 and X70 2 Diameter group (See Note 4) (c) (d) Where material grade X70 Material manufacturer For actual CE values of < 0.35, an increase of carbon equivalent of > 0.05 above that used for the procedure test weld For actual CE values of 0.35, an increase of carbon equivalent of > 0.03 above that used for the procedure test weld (see Clause 5.4.1) Change in nominal outside diameter outside the diameter groups qualified as follows: (c) D 60.3 mm 60.3 mm < D 508 mm D > 508 mm where D is the nominal diameter of the test weld 3 Wall thickness Change of material thickness (δn) in the thicker material in a joint between < 0.5 δn and > 1.2δN PROCESS 4 Welding process Change between two different arc welding processes, including a change of operation of an arc welding process from manual operation to semi-automatic or automatic operation, or vice versa. DESIGN 5 Preparation Any change to the nominal dimensions of the weld preparation including the root gap, as specified in Clause Weld shape and size Limited by joint design (See Clause 10). 7 Backing ring or consumable insert Deletion or addition of an internal backing ring or consumable insert 8 Passes Not limited if the increase or decrease in number of passes, is associated with similar material Grade, and CE but still within the essential variables of Item 1. 9 Position Change in position other than as permitted by Table 4.2(A) 10 Direction of welding Change between vertical up and vertical down (continued)

31 26 FILLER Item (see Note 1) 11 Filler metal (electrodes, filler wire) SHIELDING (c) Remarks Any change in classification of welding consumables as specified by Table Change in diameter of electrode, filler wire or rod for the root pass and for single sided butt welds and fillet welds, any change of root pass electrode For any filler metal using electrodes of higher strength than E4110, a change in either of the following: (i) (ii) The type or nominal level of alloying elements used in the weld metal Manufacturer and factory of origin 12 Shielding gas Change between one gas or mixture and another gas or mixture (c) Decrease in shielding gas flow rate by more than 10% or decrease in the nozzle or cup size Change of inert gas backing parameters for single side butt welds 13 Shielding flux Change in flux type, size, classification, or make ELECTRICAL Change in combination of flux and electrode that results in a different classification number 14 Electrical characteristics Change of polarity of the electrode PROCEDURE (c) (d) (e) (f) Change of electrical current between a.c. and d.c. Change of arc type between spray arc, globular arc, pulsating arc, and short-circuiting (dip transfer) arc Addition or deletion of a pulsating current to a d.c. power arc Change of contact tube-to-work distance Use of welding consumables outside the manufacturer' s published recommended range 15 Number of welders Decrease in number of welders used on any root pass, or hot pass, in the procedure test weld 16 Removal of line-up clamp (if used) and/or a change in the type of lift. A reduction in the proportion of root pass welded before the line-up clamp is released A change from normal to extreme lift (see Appendix F) 17 Tack welding (if used) A reduction in the size of tack welds 18 Time lapse between individual passes (see Note 2) 19 Preheating temperature and interrun temperature Increase in time lapse beyond the qualified range Decrease in material temperature of more than 25 C below or an increase of more than 50 C above that used in the procedure test weld (continued)