WELDING SHIPS / HIGH SPEED, LIGHT CRAFT AND NAVAL SURFACE CRAFT RULES FOR CLASSIFICATION OF NEWBUILDING DET NORSKE VERITAS MATERIALS AND WELDING

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1 RULES FOR CLASSIFICATION OF SHIPS / HIGH SPEED, LIGHT CRAFT AND NAVAL SURFACE CRAFT NEWBUILDING MATERIALS AND WELDING PART 2 CHAPTER 3 WELDING JANUARY 23 This booklet includes the relevant amendments and corrections shown in the January 24 version of Pt. Ch.1 Sec.3. CONTENTS PAGE Sec. 1 General Requirements... 5 Sec. 2 Welding Procedures and Approval of Welders... 7 Sec. 3 Type Approval of Welding Consumables Sec. 4 Welding of Clad Steel Plates Veritasveien 1, NO-1322 Høvik, Norway Tel.: Fax:

2 CHANGES IN THE RULES General This booklet is a reprint of the previous edition and apart from clarifications of text and the inclusion of amendments and corrections, published in the July 22 edition of Pt. Ch.1 Sec.3, no other changes have been made. This chapter is valid until superseded by a revised chapter. Supplements will not be issued except for an updated list of minor amendments and corrections presented in Pt. Ch.1 Sec.3. Pt. Ch.1 is normally revised in January and July each year. Revised chapters will be forwarded to all subscribers to the rules. Buyers of reprints are advised to check the updated list of rule chapters printed in Pt. Ch.1 Sec.1 to ensure that the chapter is current. Comments to the rules may be sent by to rules@dnv.com For subscription orders or information about subscription terms, please use distribution@dnv.com Comprehensive information about DNV and the Society's services is found at the Web site Det Norske Veritas Computer Typesetting (FM+SGML) by Det Norske Veritas Printed in Norway If any person suffers loss or damage which is proved to have been caused by any negligent act or omission of Det Norske Veritas, then Det Norske Veritas shall pay compensation to such person for his proved direct loss or damage. However, the compensation shall not exceed an amount equal to ten times the fee charged for the service in question, provided that the maximum compensation shall never exceed USD 2 million. In this provision "Det Norske Veritas" shall mean the Foundation Det Norske Veritas as well as all its subsidiaries, directors, officers, employees, agents and any other acting on behalf of Det Norske Veritas.

3 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Contents Page 3 CONTENTS SEC. 1 GENERAL REQUIREMENTS... 5 A. General...5 A 1 Scope...5 A 2 Basic requirements...5 A 3 Welding shops and -contractors...5 A 4 Welding consumables...5 B. Testing...5 B 1 General...5 B 2 Tensile testing at ambient temperature...5 B 3 Bend testing...5 SEC. 2 WELDING PROCEDURES AND APPROVAL OF WELDERS... 7 A. General...7 A 1 Scope...7 A 2 Definitions...7 B. Welding Procedures, Steel...7 B 1 Welding procedure specification, WPS...7 B 2 Welding procedure qualification test, WPQT...7 B 3 WPQT for butt welds on plates...7 B 4 WPQT for butt welds on tubes...9 B 5 WPQT for full penetration T-, Y-, and K- joints...9 B 6 WPQT for tubular joints...1 B 7 WPQT for fillet welds...1 B 8 Retesting...11 B 9 Validity of qualified welding procedures...11 B 1 Welding procedure qualification record, WPQR...12 B 11 WPQT for liquefied gas systems...13 C. Welding Procedures, Aluminium...14 C 1 General...14 C 2 WPQT for butt welds...15 C 3 WPQT for fillet welds...16 C 4 Retesting...17 C 5 HAZ softening adjacent to welds...17 D. Welding procedures, Ferritic-Austenitic Stainless Steel (Duplex)...17 D 1 General...17 D 2 Additional testing...17 D 3 Validity of a qualified welding procedure...17 E. Approval of Welders...17 E 1 General...17 E 2 Standards for approval testing...17 E 3 Certification...17 SEC. 3 TYPE APPROVAL OF WELDING CONSUMABLES A. General...18 A 1 Scope...18 A 2 Approval procedure...18 A 3 Approval testing...18 A 4 Changes...18 A 5 Basic groups and grades...18 A 6 Testing procedure...18 A 7 Test specimens...18 A 8 Hydrogen test...19 A 9 Re-testing...19 B. Covered Electrodes for Shielded Metal Arc Welding of Normal and High Strength Steels...19 B 1 General...19 B 2 All-weld-metal test...2 B 3 Butt-weld test...2 B 4 Hydrogen test...21 B 5 Covered electrodes for fillet welding...21 B 6 Covered electrodes for gravity or contact welding...22 B 7 Deep penetration electrodes...22 B 8 Annual tests...23 B 9 Upgrading...23 C. Wire/Flux Combinations for Submerged Arc Welding.. 24 C 1 General...24 C 2 Multi-run technique...24 C 3 Two-run technique...25 C 4 Annual tests...26 C 5 Upgrading...26 D. Combinations for Use in One-side Automatic Welding Processes D 1 General...27 D 2 One-run welding...27 D 3 Multi-run welding...28 D 4 One-and multi-run welding...28 D 5 Testing...28 D 6 Requirements...28 D 7 Annual tests...28 D 8 Upgrading...29 E. Wires and Wire and Gas Combinations for Metal Arc Welding E 1 General...29 E 2 Semi-automatic multi-run welding...29 E 3 Automatic multi-run welding...3 E 4 Two-run welding...31 E 5 Annual tests...32 E 6 Upgrading...32 F. Combinations for Use in Electro-slag and Electro-gas Welding Processes F 1 General...32 F 2 Initial tests...32 F 3 Annual tests...33 G. Welding Consumables for Welding of Steel Grades NV 2-4, NV 2-4L, NV 4-4 and NV 4-4L for Low-Temperature Applications G 1 General...33 G 2 Additional requirements...33 G 3 Annual tests...33 H. Welding Consumables for Low-Alloy, Heat-Resisting Steels (NV,3Mo, NV 1Cr,5Mo and NV 2,25Cr 1Mo) 34 H 1 General...34 H 2 Additional requirements...34 H 3 Chemical composition...34 H 4 Annual tests...35 I. Welding Consumables for Welding of Steel Grades NV 1,5Ni, NV 3,5Ni, NV 5Ni and NV 9Ni I 1 General...35 I 2 Additional requirements...35 I 3 Annual test...36 I 4 Other welding consumables...36 J. Welding Consumables for Welding of Extra High Strength Steels J 1 General...36 J 2 Additional requirements...36 J 3 Annual tests...37 K. Welding Consumables for Welding of Austenitic Stainless Steels K 1 General...37 K 2 All-weld-metal test...38 K 3 Chemical composition...38 K 4 Possible additional tests...38 K 5 Annual tests...38 L. Welding Consumables for Welding of Ferritic-Austenitic Stainless Steels (Duplex Steels)... 4 L 1 General...4 L 2 Test assemblies...4 L 3 Chemical composition...4 L 4 Microstructural examination...4 L 5 Corrosion test...4 L 6 Annual tests...4

4 Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 Amended, Pt.2 Ch.3 Contents Page 4 see Pt. Ch.1 Sec.3, January 24 M. Welding Consumables for Welding of Aluminium Alloys for General and Low-Temperature Service...4 M 1 General...4 M 2 Test assemblies...4 M 3 Testing...4 M 4 Annual tests...41 SEC. 4 WELDING OF CLAD STEEL PLATES A. General...42 A 1 Scope...42 B. Welding...42 B 1 Welding methods deposited metal...42 B 2 Groove preparation...42 B 3 Welding procedure...42

5 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Sec.1 Page 5 SECTION 1 GENERAL REQUIREMENTS A. General A 1 Scope 11 This Chapter specifies the requirements for welding shops and -contractors, welders, welding consumables and welding procedures in general as well as procedures and methods for welding of clad steel plates and liquefied gas systems. A 2 Basic requirements 21 Welding of important structures: hull, superstructure and deckhouse, machinery installations: boilers, pressure vessels and pipe systems and equipments: sternframes, rudders, rudder stocks and rudder horn are to be carried out by approved welders, with approved welding consumables and at welding shops and -contractors recognized by the Society. Manufacturers of boilers and pressure vessels Class I II are to obtain the approval according to a detailed programme, available by the local surveyor. A 3 Welding shops and -contractors 31 Welding shops and -contractors will have to prove their qualifications for the welding operations in question. 32 It is assumed that the welding shops and -contractors make use of the necessary equipment for carrying out inspection of the welding operations in a satisfactory manner. 33 Important welding operations are to be carried out under daily supervision of an inspector, who has the experience and qualifications which enable him to judge this type of work. The work of each welder is to be regularly examined. 34 The welding shops and -contractors are to keep a card index or register of all approved welders. The register is to give information on training of the welders and date and results of qualification tests. Information about the base metal, type of welding consumable, joint design and welding positions is to be stated in the event of re-qualification tests. The surveyor is to be allowed to examine the register at any time. A 4 Welding consumables 41 Consumables for welding of ships, mobile offshore units, fixed offshore installations and other structures intended for classification are to be approved by the Society. 42 Type approval of welding consumables will be considered subject to compliance with the requirements given in Sec All brand names under which a tested and approved welding consumable is marketed, are to be registered by the Society. In order to avoid duplication of tests, the manufacturer is to certify that the welding consumables marketed under alternative brand names are identical with the consumables tested for approval. B. Testing B 1 General 11 Testing of welds is to be carried out as specified in 2 to 3. Reference is also made to relevant paragraphs in Ch.1 Sec.2. B 2 Tensile testing at ambient temperature 21 For tensile testing of all-weld-metal and butt welds two different types of test specimens may be used, round test specimens or flat test specimens (see Fig. 1 ) as described below: A Deposited metal tensile test Normally, round test specimens with the following dimensions are to be used: d = 1 mm L o = 5 mm L c = 6 mm R 5 mm B Butt weld tensile test for testing of the weld as a whole Flat test specimens with the weld machined flush with the surface of the plate, are to be used. The dimensions are to be as follows: a = thickness of plate, t b = 25 mm L = L c = 3t or 2t + width of weld, whichever is the greatest R = 25 mm C Butt weld tensile test Flat test specimens with the weld machined flush with the surface of the plate, are to be used. The dimensions are to be as follows: a = thickness of plate, t b = 3 mm L o = 6 mm + width of weld + 6 mm R = 5 mm R R Fig. 1 Tensile test specimen. a L O L C B 3 Bend testing 31 Flat bend test specimens, as given in Fig. 2 are to be used. Edges on tension side to be rounded to a radius of 1 to 2mm. S O S O d b Round Flat

6 Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 Amended, Pt.2 Ch.3 Sec.1 Page 6 see Pt. Ch.1 Sec.3, January 24 a D 11a (~ 9a + D) Fig. 2 Bend test specimen. b 1-2 mm 1-2 mm 32 When the wrap around bend test, exemplified in Fig. 3 is used, e.g. for the side bend test of a weld, the length of the test specimen has to be greater than the length 11a shown in Fig For butt weld bend test specimens, the weld is to be machined flush with the surface of the plate. 34 For transverse face-bend and root-bend test specimens for butt weld test the dimensions are to be as follows: a = as rolled thickness t of the plate b = 3 mm If the as rolled thickness t is greater than 25 mm, it may be reduced to 25 mm by machining on the compression side of the test specimen. 35 For transverse side-bend test specimens for butt weld test the dimensions are to be as follows: a = 1 mm b = as rolled thickness t of the plate If t 4 mm, the side-bend test specimen may be subdivided, each part being at least 2 mm wide. 36 When a longitudinal face-bend or root-bend weld test is required, a test specimen according to an appropriate standard will be accepted. D Fig. 3 Wrap around bend test.

7 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Sec.2 Page 7 SECTION 2 WELDING PROCEDURES AND APPROVAL OF WELDERS A. General A 1 Scope 11 This Section specifies the requirements for welding procedures and welding procedure qualification tests as well as approval of welders. A 2 Definitions 21 Welding procedure specification (WPS): A specification of materials, detailed methods, practices and parameters employed in the welding of a particular joint. 22 Welding procedure qualification test (WPQT): A test carried out in order to demonstrate that a weld made according to a specific procedure specification meets the given requirements. 23 Welding procedure qualification record (WPQR): The record of the actual parameters employed during welding of the qualification test piece, and results from the non-destructive testing and mechanical testing. 24 Non-destructive testing (NDT): Visual inspection, radiographic testing, ultrasonic testing, magnetic particle testing, penetrant testing and other non-destructive methods for revealing defects and irregularities. l min = 4 mm L min = 1 mm Edge preparation and fit-up are to be as detailed in the WPS. The plates are to be joined and held by tack welds to provide the correct gap for the edge preparation used. 5 mm of each end of the test piece is to be discarded. 5 Discard Plate rolling direction ( Steel plates KV L -tested ) Plate rolling direction ( Steel plates KV T -tested ) L B. Welding Procedures, Steel B 1 Welding procedure specification, WPS 11 WPS subjected to approval is to contain as a minimum the following information as relevant for the welding operation: material: standard, grade and modification nominal thickness/diameter range (dimensions) welding process joint/groove design welding position and direction welding consumables: trade name, electrode/wire diameter, shielding gas, flux and recognized classification welding sequence (number and order of passes/layers) welding parameters: voltage, current, polarity and welding speed preheat and interpass temperature post weld heat treatment. B 2 Welding procedure qualification test, WPQT 21 When WPQT is required, the tests must be performed in the environment applicable to the actual production and meet the specified minimum requirements prior to commencing the production welding. 22 The qualification test is to be witnessed by the surveyor. B 3 WPQT for butt welds on plates 31 The test assembly consists of two plates welded together. As far as possible the plates are to have a size which can simulate the heat transfer during the production welding. For manual or semiautomatic welding, a test assembly according to Fig. 1 is to be carried out with: l min = 3 mm L min =35 mm For automatic welding, the dimensions are to be: 5 Discard l/2 l/2 Fig. 1 Test assembly for butt welds on plates 32 NDT is to be carried out in accordance with the specification given for the production welding in question. The extent of the testing is to be as follows: 1 % visual inspection 1 % radiographic or ultrasonic testing 1 % surface crack detection (dye penetrant or magnetic particle testing) The soundness of the weld is to comply with requirements given in the relevant parts of the Rules. 33 The following mechanical tests are required from each assembly (see Fig. 2): 1 tensile test (flat specimen transverse to the weld) 1 root and 1 face bend tests when t 2 mm and 2 side bend tests when t > 2 mm when the welding consumable is not approved, 1 extra tensile test (round specimen from the weld metal) 12 Charpy V-notch tests whith the notch location as given in 38 1 macrosection test (metallographic examination + hardness measurements). 34 Specimens for transverse tensile testing are to be in accordance with Sec.1 B21, type B. l

8 Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 Amended, Pt.2 Ch.3 Sec.2 Page 8 see Pt. Ch.1 Sec.3, January 24 The tensile strength is not to be below the specified minimum tensile strength for the steel grade in question. t Weld metal Fusion line HAZ - 2 mm HAZ - 5 mm Fig. 2 Sampling of test specimens on plates Discard 5 mm Macro / hardness test Flat tensile test Face bend test } or 2 side bend Root bend test tests Round tensile test Discard 35 The round tensile specimen is to be machined to the dimensions shown in Sec.1 B21, type A, care being taken that the longitudinal axis coincides with the intersection between the midplane of the weld, and the midplane of the plates. If the section area of the weld metal is too small to allow sampling of the round specimen, an all-weld-metal tensile test is to be carried out according to the requirements given in Sec Transverse side bend, root bend and face bend specimens are to be machined to the dimensions shown in Sec.1 B3. For a mixed or heterogeneous butt joint, longitudinal bend test specimens may replace transverse bend test specimens. The test specimens are to be bent on a mandrel with diameter 4xt, where t is the thickness of the specimen, except for extra high strength steels grades 55, 62, and 69 where the diameter is to be 5xt. The bending angle is to be at least 12. After bending, the test specimens are not to reveal any open defects in any direction greater than 3 mm. Defects appearing at the corners of a test specimen during testing are to be ignored in the evaluation. 37 The macrosection is to include about 1 mm of unaffected base material and is to be prepared and etched on one side to clearly reveal the fusion line and the HAZ. Cracks and lack of fusion are not accepted. The welded joints are to have a regular profile with smooth transitions to the base materials and without significant or excessive reinforcement. 38 The Charpy V-notch specimens are to be machined in accordance with the requirements given in Ch.1 Sec.2 (ISO } charpy V-notch specimens 5 mm 148). The specimens are to be sampled 2 mm below the surface of the parent material and transverse to the weld. 12 Charpy V-notch specimens are to be localized in the welded joint as follows: 3 specimens with the notch along the weld metal centreline 3 specimens with the notch in the fusion line 3 specimens with the notch in the HAZ, 2 mm from the fusion line (Note 1) 3 specimens with the notch in the HAZ, 5 mm from the fusion line (Note 1). Guidance note: HAZ impact test specimens are normally not required for grade NV A steels. If tested the average value for absorbed energy in weld metal, fusion line and HAZ is not to be less than 27 J at 2 C. ---e-n-d---of---g-u-i-d-a-n-c-e---n-o-t-e--- The V-notch is to be perpendicular to the plate surface. For plate thicknesses >5 mm and for one side welded assemblies with plate thickness >2 mm, one additional set of specimens is to be taken in the weld metal root area. Hull construction The test temperature and absorbed energy are to be in accordance with the following requirements: Impact test temperatures: +2 C for grades B, A27S, A32, A36 and A4 C for grades D, D27S, D32, D36 and D4-2 C for grades E, E27S, E32, E36 and E4-4 C for grades F32, F36 and F4 The average value for absorbed energy in weld metal, fusion line and HAZ is not to be less than: for manual and semi-automatic welding in all welding positions except vertical: 47 J for automatic welding: 34 J (NV 4 grades 41 J) for manual and semi-automatic welding in vertical position: 34 J (NV 4 grades 41 J). For extra high strength structural steels the Charpy V-notch test temperature and the average value for absorbed energy in weld metal, fusion line and HAZ are to be the same as required for the base material. Pressure vessels and production/drilling plants related equipment, structures and systems The Charpy V-notch test temperature and the average value for absorbed energy in weld metal, fusion line and HAZ are to be the same as required for the base material. 39 In the case of reduced Charpy V-notch test specimens (1 x 7,5 mm and 1 x 5 mm), the impact energy values to be obtained are to satisfy the following table: Table B1 Impact energy requirement for subsize specimens Dimensions of Charpy V-notch test specimen Impact energy 1 x 1 mm KV 1 x 7.5 mm 5/6 KV 1 x 5 mm 2/3 KV 31 The average impact requirements are to be satisfied for each notch location, but one single value of three values from

9 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Sec.2 Page 9 specimens from the same notch location may be below the average requirements, but not below 7 % of minimum average. 311 Where the results from a set of three impact test specimens do not comply with the requirements, an additional set of three impact test specimens may be taken. The results obtained are to be combined with the original results to form a new average which, for acceptance, is to be not less than the required value. Additionally, for these combined results not more than two individual values are to be less than the required average value, and of these, not more than one is to be less than 7 % of the average value. Further re-tests may be made at the surveyor's discretion, but these are to be made on a new welded assembly (revised WPS) and are to include all tests required for the original assembly, even those which were previously satisfactory. 312 The hardness testing is to be in accordance with ISO 657/1 or equivalent, and is only required for grades NV27S and higher. Normally, the Vickers method (HV5 or HV1) is used. Indentations are to be made along traverses in the weld, HAZ and the parent metal approximately 1 mm below the surface. For each traverse a minimum of 3 indentations are to be made in the weld, HAZ (both sides) and parent metal (both sides). For HAZ the first indentation is to be placed as close to the fusion line as possible. The values are to be reported for consideration. 313 When a butt weld is made between two plates of different grades, the test temperature and achieved impact energy are to comply with the minimum specified requirements for the lower steel grade (see 38). In the same way, the tensile strength to be obtained on the welded assembly is to be in agreement with the requirements relating to the plate steel having the lower strength. As an example the test temperature, impact energy and tensile strength for the butt welded joints given in Fig. 3 are those required for the plate of grade D in the left assembly and for the plate of grade E in the right assembly. Edge preparation and fit-up as detailed in the WPS Fig. 4 Test assembly for butt welds on tubes a a = minimum value 15 mm D = outside diameter 42 NDT is to be carried out in accordance with the specification given for the production welding in question. The extent of the testing is to be as follows: 1 % visual inspection 1 % radiographic or ultrasonic testing 1 % surface crack detection (dye penetrant or magnetic particle testing) The soundness of the weld is to comply with requirements given in the relevant parts of the Rules. 43 The following mechanical tests are required from each assembly (see Fig. 5): 1 tensile test (flat specimen transverse to the weld) 1 root and 1 face bend tests when t 2 mm and 2 side bend tests when t > 2 mm 12 Charpy V-notch tests whith the notch location as given in 38 1 macrosection test (metallographic examination + hardness measurements). a D grade D grade E WELD METAL FUSION LINE HAZ - 2 mm CHARPY V-NOTCH TESTS HAZ - 5 mm grade E grade EH Fig. 5 Sampling of test specimens on tubes BEND TESTS TENSILE TEST HARDNESS/MACRO TEST Fig. 3 Butt welded plate joints of different grades B 4 WPQT for butt welds on tubes 41 The test assembly is to be in accordance with Fig The results of mechanical testing are to comply with the relevant requirements given in 3. B 5 WPQT for full penetration T-, Y-, and K- joints 51 WPQT's for full penetration groove welds between plates at right angles or inclined, i.e. T- or Y- and K- configurations, are to cover a weld length of minimum 35 mm (see

10 Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 Amended, Pt.2 Ch.3 Sec.2 Page 1 see Pt. Ch.1 Sec.3, January 24 Fig. 6). 52 NDT is to be carried out in accordance with the specification given for the production welding in question. The extent of the testing is to be as follows: 1 % visual inspection 1 % ultrasonic testing 1 % surface crack detection (dye penetrant or magnetic particle testing). The soundness of the weld is to comply with requirements given in the relevant parts of the Rules. a = 3t; minimum value 15mm b = 6t; minimum value 35mm B 6 WPQT for tubular joints 61 The test assembly is to be in accordance with Fig NDT is to be carried out in accordance with the specification given for the production welding in question. The extent of the testing is to be as follows: 1 % visual inspection 1 % ultrasonic testing 1 % surface crack detection (dye penetrant or magnetic particle testing). The soundness of the weld is to comply with requirements given in the relevant parts of the Rules. a = minimum value 15mm D1 = outside diameter of the greater tubular (can) t1 = wall thickness of the can D2 = outside diameter of the smaller tube (brace) t2 = wall thickness of the brace D2 Edge preparation and fit-up as detailed in the WPS t2 b a a a 12 α 9 6 a D1 b t1 Edge preparation and fit-up as detailed in the WPS Fig. 6 Test assembly for full penetration T-joints 53 The following mechanical tests are required from each assembly (see Fig. 7): 12 Charpy V-notch tests with the notch location as given in 38 1 macrosection test (metallographic examination + hardness measurements). 54 The results of mechanical testing are to comply with the relevant requirements given in 3. WELD METAL FUSION LINE CHARPY V-NOTCH HAZ - 2 mm TESTS HAZ - 5 mm HARDNESS MACRO TESTS Fig. 8 Test assembly for tubular joints 63 The following mechanical tests are required from each assembly (see Fig. 8): 12 Charpy V-notch tests sampled at 9 o'clock and with the notch location as given in 38 two macrosection tests (metallographic examination + hardness measurements) at 12 and 6 o'clock. 64 The results of mechanical testing are to comply with the relevant requirements given in 3. B 7 WPQT for fillet welds 71 The two plates are assembled and positioned edgewise so as to constitute a tee-assembly with no clearance. As far as possible the plates are to be of a sufficient size to ensure a reasonable heat distribution. For fillet welds the test assembly is to be as defined in Fig L a Fig. 7 Sampling of test specimens on full penetration T-joints 15 Fig. 9 Test assembly for fillet welds

11 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Sec.2 Page 11 For manual and semi-automatic welding the length of the test piece is to be: L min. = 35 mm For automatic welding the length is to be: L min. = 1 mm Weld and fit-up are to be as detailed in the WPS. The test assembly is to be welded on one side only. For manual and semi-automatic welding, the stop/restart position is normally to be included in the test length and is to be clearly marked for subsequent examination. The ends of the specimen are exempted from examination over a length of 5 mm. 72 NDT is to be carried out in accordance with the specification given for the production welding in question. The extent of the testing is to be as follows: 1 % visual inspection 1 % surface crack detection (dye penetrant or magnetic particle testing). The soundness of the weld is to comply with the specified requirements given in the relevant parts of the Rules. If the stop/restart spot is included in the test length, special attention is to be paid to this position with respect to profile, proper fusion and absence of crater defects. 73 The following tests are to be performed: two macrosection tests (metallographic examination, hardness measurements). One of the macrosections is to be taken at the marked position of the stop/restart (for more details see 37). For hardness testing, see 312. B 8 Retesting 81 If the WPQT fails to comply with any of the requirements for NDT one extra WPQT is to be welded and subjected to the same testing. If this additional test does not meet the relevant requirements, the actual WPS is to be considered as not qualified and a respecification of the WPS is to be made prior to a new qualification test. B 9 Validity of qualified welding procedures 91 The validity of a qualified welding procedure is to be restricted to the workshop performing the qualification. Workshops or workshop branches under the same technical management and working in accordance with the same QAprogram and -procedures are considered as one workshop. 92 Qualification of a welding procedure remains valid provided the parameters are kept within the qualified ranges during production welding. The qualified ranges are given in 93. When one or more variations outside the qualification ranges occur, the welding procedure qualification is to be considered invalid, and the welding procedure is therefore to be respecified and requalified. 93 A qualified welding procedure is to be used within the ranges of the parameters below. Base material The following changes are to lead to a new qualification: a) In general, significant change of material properties which will obviously affect the weldability and mechanical properties. b) More specifically, structural steels are grouped in three categories: i) Normal strength steel, grades A, B, D and E or equivalent structural steels with tensile strength 4 52 N/mm 2. ii) High strength steel, grades A27S, D27S, E27S, A32, D32, E32, F32, A36, D36, E36, F36, A4, D4, E4, F4 or equivalent structural steels with minimum specified yield strength N/mm 2. iii) Extra high strength steels, grades A-F 42, A-F 46, A-F 5, A-F 55, A-F 62, A-F 69 or equivalent structural steels with minimum specified yield strength N/mm 2. The qualification on steel grades of higher toughness requirements will qualify the grades of lower toughness but not vice versa. Thickness Thickness, t, is defined as follows: a) For a butt weld: The base metal thickness, which for welds between dissimilar thicknesse s is that of the thinner material. b) For a fillet weld: The base metal thickness, which for welds between dissimilar thicknesses is that of the thicker material. However, for each thickness range qualified, as in Table B2 there is an associated range of qualified throat thickness as given below. c) For a set-on tubular joint: The thickness of the brace d) For a set-in or set-through tubular joint: The thickness of the can e) For a T-butt joint in plate: The thickness of the prepared plate The requirements to qualified thickness range for butt welds are to be as given in Table B2. Table B2 Qualified thickness range Qualification range Thickness t in mm for single run for multi-run of test piece or single run welding from both sides and all fillet welds t < 12.8 t to 1.1 t up to 2 t 12 t 1.8 t to 1.1 t.5 t to 2 t (max. 15) t > 1.8 t to 1.1 t.5 t to 1.5 t 1) The qualification range for vertical downward position is.5 t to 1.1 t The requirements to qualified thickness range for fillet welds are in addition to the requirements of Table B2, that the throat thickness, a, is to be in the range.75 a to 1.5 a. However, a throat thickness of 1 mm or more is to give qualification for all throat thicknesses above or equal to 1 mm. Diameter of tubes and tubular joints The qualification of a welding procedure test on diameter D is to include qualification for diameters in the following ranges as given in Table B3. Table B3 Qualified range for tube and tubular joint. Diameter of the test piece D (mm) 1) 2) Qualification range D D to 2 D D > D and plates 1) D is the outside diameter of the tube or outside diameter of the brace. 2) Qualification given for plates also covers tubes when the outside diameter is greater than 5 mm. Angle of tubular joints

12 Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 Amended, Pt.2 Ch.3 Sec.2 Page 12 see Pt. Ch.1 Sec.3, January 24 A WPQT carried out on a tubular joint with angle α is to qualify all tubular joint angles in the range of α α 1 9 Welding consumables The following changes are to lead to a new qualification: any change in consumable grading change of consumable name when impact testing is required at temperatures below 2 C any significant change of mixture/composition (e.g. change from argon/mixed gas to CO 2 gas), flow rate, filling time and filling volume for shielding and backing gases. Welding positions The following changes are to lead to a new qualification. Change from one principal welding position (see Figs. 1, 11, 12) to another, unless complying with Table B4. Type of joint The range of approval for type of joint is given in Table B5. In addition the following changes are to lead to a new qualification: change from fillet weld to butt weld change of specified type of groove, root face and gap which may significantly affect penetration, fusion and delution of the weld. Welding condition The following changes are to lead to a new qualification: any change of welding process change from spray arc to short arc or pulsed arc or vice versa change beyond ±15 % for voltage and current, and change of more than ±1 % for travel speed change of preheating/interpass temperature beyond ±25 C change of post weld heat treatment parameters. B 1 Welding procedure qualification record, WPQR 11 The parameters used during qualification welding, NDT-records and mechanical testing reports are to be presented in a WPQR for each qualification test. The WPQR is to contain sufficient references to establish where, when, how and by whom the test welding, NDT- and mechanical testing were performed. 1G FLAT 3G VERTICAL THROAT OF WELD VERTICAL AXIS OF WELD HORIZONTAL AXIS OF WELD HORIZONTAL FLAT POSITION 1F Note: One plate must be horizontal HORIZONTAL POSITION 2F AXIS OF WELD VERTICAL 2G HORIZONTAL - VERTICAL Fig. 1 Plate test positions 4G OVERHEAD AXIS OF WELD HORIZONTAL Note: One plate must be horizontal VERTICAL POSITION 3F OVERHEAD POSITION 4F Fig. 12 Positions of test plate for fillet welds 1G ROTATING PIPE, HORIZONTAL AXIS 5G FIXED PIPE, HORIZONTAL AXIS 45 o 2G FIXED PIPE, VERTICAL AXIS 6G FIXED INCLINED PIPE Fig. 11 Pipe test positions

13 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Sec.2 Page 13 Table B4 Qualified principal positions for butt welds and fillet welds Test weld Joint configuration 1) 2) Principal Butt welds on plates Butt welds in tubes Fillet welds positions 2G+3G 1G 2G 3G 4G 2G + 5G = 6G 1G 2G 5G 2F+3F 1F 2F 3F 4F 5F Plates All 1G 1G, 2G, 4G 3G 1G, 4G All 1G 1G, 2G, 4G All 1) Tubes with OD > 5 mm are considered equivalent to plates (apply only to the can in tubular joints) 2) Tubular joints are to be qualified separately. 3) The vertical downwards position is to be qualified separately. Qualified positions 3) Butt welds Tubes All 1G 1G, 2G Not applicable 1G All 1G 1G, 2G 1G, 5G Fillet welds Plates/tubes All 1F 1F, 2F, 4F 3F 1F, 4F All 1F 1F, 2F, 4F All All 1F 1F, 2F, 4F 3F 1F, 4F All Table B5 Range of approval for type of joint Range of approval Butt welds on plate T butt welds on plate Buttwelds on pipe Type of joint in approval test piece Welded from one side Welded from both sides Welded Welded from one from both Welded from one side side sides With backing B 11 WPQT for liquefied gas systems 111 Welding shops which intend to build welded cargo tanks, process pressure vessels and/or piping systems for liquefied gases are to carry out WPQT for all types of butt welds in the construction. 112 For butt welds in tanks and pressure vessels, the test assemblies consist of two plates, each having a width of at least 15 mm and a length sufficient for making all necessary test specimens described in 115. The test assemblies are to be so prepared that the principal direction of rolling is parallel to the direction of welding. Guidance note: The test plates must be of such dimensions that the cooling condition as far as possible will be the same as for the production welding. ---e-n-d---of---g-u-i-d-a-n-c-e---n-o-t-e--- No backing With gouging No gouging With backing With Welded backing * - x x - x - - from one side No Butt weld backing x * x x x x - - on plate With Welded gouging - - * x x x - - from both sides No gouging * - x - - With Butt weld Welded backing x - x x - x * - on pipe from one side No backing x x x x x x x * T butt Welded from one side * x - - weld on Welded from both plate sides * - - Key: * indicates the WPS which is approved in the approval test X indicates those welds for which the WPS is also approved - indicates those welds for which the WPS is not approved No backing 113 For butt welds in piping systems the test assemblies are made by welding together two approximately 15 mm long pipes with the same diameter as the pipes used in the system to be represented. 114 The test assemblies are to be subjected to radiographic testing after welding. X-rays, fine-grained film and lead screens are to be used for this testing. The radiographs are at least to meet the requirements in Pt.5 Ch.5 Sec.5 and Pt.5 Ch.5 Sec.6 of the Rules for Classification of Ships. Concerning magnetic particle, dye penetrant and ultrasonic testing reference is made to Pt.5 Ch.5 Sec.5 of the Rules for Classification of Ships. Hardness testing is to be performed on weld metal, heat affected zone and parent material. The values are to be reported for consideration. The weld is to be etched through the whole cross-section and is to show normal structure and penetration. The etching is to

14 Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 Amended, Pt.2 Ch.3 Sec.2 Page 14 see Pt. Ch.1 Sec.3, January 24 be done in such a way that the fusion line is clearly seen. 115 From each test assembly for plates the following specimens are to be taken: one transverse weld tensile test specimen two side bend test specimens. The test specimens are to be cut transverse to the longitudinal axis of the weld. The thickness of the test specimen is to be 1 mm and width equal to the plate thickness. If the plate thickness exceeds 4 mm the test sample may be divided into two, each having a width of at least 2 mm five sets of Charpy V test specimens (each set consists of 3 specimens) macrosection, microsection and hardness survey may also be required. The Charpy V test specimens are to be cut with their longitudinal axis transverse to the longitudinal axis of the weld. When practicable, the test specimen is to be taken at a place half the distance from the centre to the surface of the plate. The notch is to be cut in a face of the test specimen originally perpendicular to the rolled surface. The specimens are to be taken at the following locations: 3 specimens with the notch in the centre line of the welds 3 specimens with the notch in the fusion line 3 specimens with the notch 1 mm from the fusion line 3 specimens with the notch 3 mm from the fusion line 3 specimens with the notch 5 mm from the fusion line. For austenitic chromium-nickel steels, only 3 tests with the notch in the centre of the welds are required for design temperature below 15 C. 116 From each test assembly for tubes, the following test specimens are to be taken: one transverse weld tensile test specimen two side bend test specimens. The test specimens are to be cut transverse to the longitudinal axis of the weld. The thickness of the test specimens is to be 1 mm and the width equal to the wall thickness. If the wall thickness is less than 1 mm the side bend test is to be replaced by root bend test five sets of Charpy V test specimens (each set consists of 3 specimens). The test specimens are to be cut as stipulated in 115 macrosection, microsection and hardness survey may also be required. For austenitic chromium-nickel steels, only 3 tests with the notch in the centre of the welds are required if the design temperature is below 15 C. 117 The butt weld tensile test is to comply with the following requirements: Generally, the tensile strength is not to be less than the specified minimum tensile strength for the parent material. In cases where the Society has approved the use of welding consumables which give lower tensile strength in the weld metal than that required for the parent material, the approved value for the welding consumable in question applies. The position of fracture is to be reported. 118 The bend test specimens are to be capable of withstanding bending through an angle of 18 over a former with diameter four times the thickness of the specimen. The tests can be considered as complying with the requirements if, after bending, no crack or other open defects exceeding 3 mm in dimension can be seen on the outer surface. 119 Charpy V testing is to be conducted at the temperature prescribed for the base material. See Pt.5 Ch.5 Sec.2 of the Rules for Classification of Ships. When specimens of 1 x 1 mm cross-section are used, the average value from 3 tests is not to be less than 27 J for weld metal. One single test may give a value below the required average but not lower than 19 J. For fusion line and heat affected zone the requirement for minimum average value is the same as for the base material. Only one individual value may be below the specified average value provided it is not less than 7 % of that value. For testing of thin materials where it is impossible to use a standard test specimen 1 x 1 mm, the larger of the following specimens is to be used: 1 x 7.5 mm, 1 x 5 mm, 1 x 2.5 mm. The impact values are then reduced to respectively 5/6, 2/3 and 1/2 of the required values of the standard test specimen. C. Welding Procedures, Aluminium C 1 General 11 Qualified welding procedures are required for all important joints in hulls and structures which are to be classed with Det Norske Veritas. The procedure tests are to be representative of the following: each base material/alloy and temper used in production the thickness and diameter range in question (see Tables B2 and B3 each type of consumable and welding process welding position (see Table C1) joint/groove design number of passes preheat (if any) volt-ampere characteristics shielding gas. Table C1 Qualified principal positions for butt welds and fillet welds Test weld Qualified positions Joint configuration Principal positions Butt welds, plates Butt welds, tubes Fillet welds Butt welds on plates 1G 2G 3G 4G 1G 1G, 2G, 3G 1G, 2G, 3G All 1G 1F 1F, 2F, 3F 1F, 2F, 3F All Butt welds in tubes 1G 2G 5G Fillet welds 1F 2F 3F 4F 5F 1) The vertical downwards position is to be qualified separately. 1G 1G, 2G, 3G All 1G 2G 1G, 5G 1F 1F, 2F, 3F All 1F 1F, 2F, 3F 1F, 2F, 3F All All

15 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Sec.2 Page 15 C 2 WPQT for butt welds 21 Each test assembly consists of 2 plates with dimensions 3 x 15 mm. The plates are to be joined with a longitudinal butt weld. For extruded sections and pipes the assembly is to consist of 2 sections each 15 mm long (see Figs. 13 and 14). 22 The welding is to be carried out in accordance with the procedure to be used during production. Welding consumables are those recommended in Table C2. 23 The joint configurations are to comply with those intended to be applied for the production welding. 24 If back-sealing run is to be laid, this run is to be laid in the same position as for the respective weld. 25 The welds are to be subjected to visual inspection, dye penetrant testing and ultrasonic- or X-ray testing. The requirements to quality level for imperfections are to be as given in ISO level B. 26 Side-bend tests are to be carried out for thickness equal to and above 1 mm. Two bend specimens are to be taken from each of the welded assemblies. Table C2 Selection of suitable consumables for combinations of aluminium alloys Base Metal Alloy NV-552, NV-5754 NV-5154, NV-5454 NV-586 NV-583 NV-5383 NV-66, NV-661 NV-663, NV-65A NV-682 NV-552, NV , 5556, , 5556, , 5556, 5183 NV-5154, NV-5454 NV-586 NV-583, NV , 5556, ) 5356, 5556, 5183 NV-66, NV-661 NV-663, NV-65A NV , 5556, , 5556, , 5556, 5183 Note: All consumables here are covered by the AWS specification. The prefix «ER» is omitted. 1) Other consumables may be used if allowable stresses are reduced, see Table C4. Welding direction Discard 25mm Area 1 for: - 1 tesile specimen - 1 root and 1 face or 2 side bend specimens Area 2 for: - Additional test specimens if required 28 Requirement: No cracks or open defects exceeding 3 mm measured on the convex surface after bending are accepted. Smaller cracks developing from the edges of the specimens are not normally considered as significant, unless there is definite evidence that they result from inclusions or other defects. «Wrap around» bending as shown in Fig. 15 is the preferred bending method. Top for fixed pipe Discard 25mm Area 3 for: - 1 macro test specimen Fig. 13 Location of test specimens for a butt weld on plate 27 For thickness below 1 mm one face bend and one root bend test specimens are to be taken. The width is to be 3 mm and the thickness equal to the plate thickness. The diameter of the bending mandrel is to be as given in Table C3. Table C3 Former diameter for bend tests Condition Base metal alloy, H111 H116, H32 H321, H34 T4 T5, T6 NV-552, NV-5754 NV-5154, NV t 4t - - NV-586, NV-583, NV t 6t - - NV-66, NV-661 NV-663, NV-65A NV t 7t Fig. 14 Location of test specimens for a butt weld in pipe Area 1 for: - Additional test specimens if required Area 2 for: - 1 tesile specimen - 1 root and 1 face or 2 side bend specimens Area 3 for: - 1 macro test specimen

16 Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 Amended, Pt.2 Ch.3 Sec.2 Page 16 see Pt. Ch.1 Sec.3, January 24 T shown in Fig. 16. T WELD T C ROLLER A > 4 x T T + 2mm 1 GAUGE LENGTH ( ~ 3 x T ) 1 Fig. 16 Tensile test specimen Fig. 15 «Wrap around» bending B = 1/2 A + T 29 One tensile specimen is to be taken from each of the welded assemblies. The test specimen, 25 mm wide and with full plate thickness and orientated transverse to the weld, is 21 The tensile strength of the test specimens is not to be less than specified for the parent alloy in Table C One macrosection is to be prepared from the test assembly to reveal the weldment macro structure. The macrosection is to be visually inspected using a magnification of 5 to 1X. The macrosection is to show a regular weld profile with a smooth transition to the base material without significant undercut or excessive reinforcement and show thorough fusion between adjacent layers of weld metal and base metal. There are to be no cracks, lack of fusion and incomplete penetration. Table C4 Mechanical properties in the welded condition Alloy Temper Filler Tensile strength R m minimum Yield strength in HAZ, R p,2 minimum (N/mm 2 ) (N/mm 2 ) NV-552,F, H111, H32, H34 NV-5754,F, H111, H NV-5154A, H NV-5454,F, H111, H34, NV-586,F, H111, H116, H32, H34 NV-583, F t < 6 mm, F t > 6mm H116, H321 H116, H321 NV-5383, H111, H116, H NV-66 T NV-661 T4 T5 or T NV-663 T5 T NV-65A T5 or T NV-682 T4 T5 or T C 3 WPQT for fillet welds 31 The two plates are assembled and positioned edgewise so as to constitute a tee-assembly with no clearance. As far as possible the plates are to be of a sufficient size to ensure a reasonable heat distribution. For fillet welds the test assembly is to be as defined in Fig. 9. For manual and semi-automatic welding the length of the test piece is to be: L min. = 35 mm For automatic welding the length is to be: L min. = 1 mm Weld and fit-up are to be as detailed in the WPS. The test assembly is to be welded on one side only. For manual and semi-automatic welding, the stop/restart position is normally to be included in the test length and is to be clearly marked for subsequent examination. The ends of the specimen are exempted from examination over a length of 5 mm. 32 NDT is to be carried out in accordance with the specification given for the production welding in question. The extent of the testing is to be as follows: 1 % visual inspection 1 % surface crack detection (dye penetrant). The soundness of the weld is to comply with ISO level B. If the stop/restart spot is included in the test length, special attention is to be paid to this position with respect to profile, proper fusion and absence of crater defects.

17 Amended, Rules for Ships / High Speed, Light Craft and Naval Surface Craft, January 23 see Pt. Ch.1 Sec.3, January 24 Pt.2 Ch.3 Sec.2 Page The following tests are to be performed: 2 macrosection tests (metallographic examination). One of the macrosections is to be taken at the marked position of the stop/restart (for more details see B37). C 4 Retesting 41 If any of the tests do not satisfy the specified requirements, new procedure tests in duplicate may be carried out. The results of both retests are to meet the specified requirements, otherwise the test is to be rejected. C 5 HAZ softening adjacent to welds 51 The strength of a weldment is a function of the welding process, filler metal and the aluminium alloy in question. For design purposes it is assumed that around each weld there is a zone, the HAZ, in which the strength is reduced. The extent of the HAZ is assumed to have the same width as the weldment plus the plate thickness in each direction of the weld as shown in Fig. 17. If the yield strength is to be measured for information this is to be carried out on a gauge length 2 t + W of the weld (approximately 3 t). Fig. 17 Extent of HAZ t W t = plate thickness W = width of weld D. Welding procedures, Ferritic-Austenitic Stainless Steel (Duplex) D 1 General 11 Welding shops which intend to build welded cargo tanks, parts of hull structure, process pressure vessels or piping systems in Ferritic-Austenitic stainless steels are to carry out WPQT for all types of butt welds and essential fillet welds in the construction. See Sec The WPQT's are to cover all relevant dimensions, positions and material combinations. Details regarding essential variables, validity of the procedure and mechanical testing are to be as described in B with additional requirements as listed in 2. D 2 Additional testing 21 Butt welds and fillet welds are to be corrosion tested according to ASTM G48-76 Method A. The test specimen is to be in the as welded state after normal weld cleaning operation. The test specimens are to be exposed to the solution at a constant temperature of 2 C for 24 hours. Test requirements : no pitting attack is to be visible on the test face(s) general weight loss is not to exceed 2 mg. t Guidance note: Welds between Ferritic-Austenitic steels and other grades of stainless or C/Mn steels may not need to be corrosion tested. ---e-n-d---of---g-u-i-d-a-n-c-e---n-o-t-e Impact testing as described in B3. Impact test temperature -2 C. The average value for absorbed energy is not to be less than 27 J. 23 Microstructural examination The test samples are to comprise the weld metal, heat affected zone and base metal. The microstructure is to be suitably etched and examined at 4X magnification and is to be free from grain boundary carbides and precipitates. The ferrite content in the weld metal root and unreheated weld cap is to be determined in accordance with ASTM E 562 and be in the range of 25-7%. D 3 Validity of a qualified welding procedure 31 Reference is made to B9 and any change in the following additional essential variables which are to lead to a new qualification : variation in the heat input greater than ±15%. E. Approval of Welders E 1 General 11 These requirements apply to the Society's approval of welders for fusion welding of steel and non-ferrous metals. The welding processes for which qualifications are required include those which are designated as manual or partly mechanized welding. Welders are to pass an approval testing in accordance with 2. Yards and workshops are required to keep records of the welders' qualifications and, when required, furnish copies of valid welders' certificates. 12 Welding operators using fully mechanized or fully automatic processes need generally not pass an approval testing. However, operators are to receive adequate training in setting or programming and operating the equipment. Appropriate records of training are to be maintained. Yards and workshops may be required to furnish valid approval test certificates. E 2 Standards for approval testing 21 Welders are to be tested to a standard recognised by the Society, e.g. EN 287, ISO 966, ASME Section IX, ANSI/ AWS D Recognition of other standards is subject to submittal to the Society for evaluation. E 3 Certification 31 Welding and testing of weld assemblies are to be performed in the presence of the surveyor. Upon successful completion, the Society will certify that the welder has passed the approval testing. 32 Where certification is performed by other IACS members or independent organisations, e.g. accredited or nationally approved certification bodies, recognition of such certification will be evaluated on a case by case basis. The Society reserves the right, however, to require verification of welders' qualifications when deemed necessary. Such verification may include testing prior to production, extra NDT and/or welding production tests.