SECTION g_WELDING PROCEDURE AND WELDER QUALIFICATIONS

9.1 Def¡nitions

ln this standard, terms relaüng to welding shall be interpreted as def¡ned in Secüon lX of üe ASME Code Additionalterms are defined ¡n 9.1.1 and 9.1 .2.

9.1.1 An anglejo¡nt is a jo¡nt between two members that ¡ntersect at an angle between 0 degrees (a bunjo¡nt) and90 degrees (a cornerjoint).

9.1.2 Porosity refers to gas pockets or vo¡ds in metal.

9.2 Qualification of Weld¡ng Procedures

9.2.1 General Requ¡rements

9.2.1.1 The erection Manufacturer and the fabrication Manufacturer ¡f other than the erection Manufacturer, shallprepare weld¡ng procedure spec¡f¡cat¡ons and shall perfom tests docurnented by procedure qualmcation records tosupport the specifications, as required by Sect¡on lX of the ASME Code and any addit¡onal provis¡ons of th¡sstandard. lf the Manufacturer is part of an organizat¡on that has, to the Purchaser s saüsfaction, established eflectiveoperational control of the qualification of weld¡ng procedures and of welder performance for two or rnore companies ofdifferent names, üen separate weld¡ng procedure qualmcations are not requ¡red, prov¡ded all other requ¡rements of9.2, 9.3, and Secl¡on lX of the ASME Code arc met. Weld¡ng procedures for ladder and plaúorm assembl¡es,handrails, stairways, and other m¡scellaneous assemblies, but not their attachments to the iank, shall comply witheither AWS D1.1, AWS Dl.6, or Section lX of the ASME Code including the use of standard WPSS.

9.2.1.2 The welding procedures used shall produce weldments with the mechanical propert¡es requ¡red by thedesign.

9.2.1.3 Mateial specificat¡ons listed in Secüon 4of th¡s standard but not included in Table QW-422 of Secüon lXofthe ASME Code shall be comidered as Pl material wiü group numbers assigned as follows according to them¡nimum tensile stsength specified:

a) less than 485 MPa (70 ksi)-Group 1;

b) equal to or greater than 485 MPa (70 ksi) br¡t less üan 550 MPa (80 ksi)-Group 2;

c) equal to or greater than 550 MPa (80 ks¡)-Group 3.

Separate welding procedures and peformance qualifications shall be conducted for A841lvUA84l mater¡al.

9.2.1.4 welding variables (¡nclud¡ng supplementary essential variables when ¡mpact tests are required by 9.2.2), asdef¡ned by QW-250 of Seaion lX of the ASME Code shall be used to determine the welding procedure specif¡cationsand the procedure qual¡ficat¡on records to be instihjted. ln add¡t¡on, when ¡mpact tests of the heat-affected zone arerequired, the heat-treated condition ofthe base materialshallbe a supplementary essent¡al variable. Plates producedby the contolled-rolled process are not to be cons¡dered as hav¡ng received any heat treatment. lf a protectivecoat¡ng has been applied to weld edge preparat¡ons, the coating shall be included as an essential variable of theweld¡ng procedure spec¡f¡cation. as required by 7.2.1 .9.

9.2.2 lmpact Tests

9.2.2.1 lmpact tests for the qualificat¡on of welding procedures shall comply with the applicable provisions of 4.2.9and shall be made at or belo^r the des¡gn metal temperature.

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API SIANDARD 650

9.2.2.2 When impact testing of a material ¡s requ¡red by4.2.9,4.2.10, or 4.5.4 impact tesE of the heat-affected zone

shall be made for all rnach¡ne, automaüc, and sem¡automatic weld¡ng procedures.

9.2.2.3 Fq all mater¡als to be used at a design metal temperature below 10'C (50'F), the qualif¡cation of theweld¡ng procedure for verticaljo¡nts shall ¡nclude lmpact tests of the weld metal. lf verticaljcints are to be rn¿¡de by a

machine, aúomatic, or sem¡automaüc process, ¡mpact tests of the heat-affected zone shall also be made.

9.2.2.4 When the design metal temperature is below -7 'C (20 "F), impact tests of the weld metal shall be made forall procedures used for welding the components l¡sted in 4.2.10.1, for welding attachments to these componen§, and

for fabricaüng shell nozzles and manholes from pipe and forgings l¡sted in 4.5.

9.2.2.5 lmpact tests shall show minimum values for acceptance in accordance with 4.2.9.3 and the follotttring:

a) for P1, Group 1, materials-2o J (15 ñ-lbf), average of three spec¡mens;

b) for Pl, Group 2, materials-27 J (2O ft-lbf), average of three specimens;

c) for P1, Group 3, materials-34 J (25 ft-lbf), average of üree specimens.

For shell plates thicker than 40 mm (11/2 ¡n.), these values shall be increased by 7 J (5 ftlbf) for each 13 mm (1/z in.)

over 40 mm (11/2 in.). lnterpolation is permitted.

9.2.2.6 Weld-metal ¡mpact spec¡mens shall be taken across the weld with one face substantially parallel to and

within 1.5 mm (1/lo in.) of the surface of the material. The notch shall be cut normal to the original material surface

and w¡th the weld metal entirely within the fracture zone.

9.2.2.7 Heat-affected-zone impact specirnens shall be taken across the weld and as near the sulace of the material

as ¡s practicable. Each sp€c¡men shall be etched to locate the heat-afiected zone, and the notch shall be cut

approximately normal to the original mater¡al surface and with as much heat-affected-zone material as possible

¡ncluded ¡n the fracture zone.

9.2.2.8 Production welding shall conform to the qualmed weld¡ng procedure, but product¡on-weld test plates need

not be made.

9.3 Qual¡f¡cát¡on of Welders

9.3.1 The erection Manufacturer and the fabricafon Manufacturer, if other than the erection Manufacturer, shall

conduct tests for all welders assigned to manual and semiautomatic weld¡ng and all weld¡ng operators ass¡gned to

mach¡ne and automatic weld¡ng to demonstrate the welders'and welding operators' ab¡lity to make acceplable welds.

Tests conducted by one Manufacturer shall not qually a welder or welding operator to do work for another

ManrJfaclurer.

9.3.2 The welders and weld¡ng operators who weld pressure parts and join nonpressure parts, such as allpermanent and temporary cl¡ps and lugs, to pressure parts shall be qualified ¡n accordance with Seoion lX of theASME Code.

9.3.3 The records of the tests for qualifying welders and welding operators shall ¡nclude the follovúing.

a) Each welder or weld¡ng operator shall be ass¡gned an idenüfy¡ng number, letter, or symbol by the fabrication orerect¡on Manufacturer.

b) The fabrication or erect¡on Manufacturer shall maintain a record of the welders or weld¡ng operators employed

üat shows the date and resuhs of the tests for each welder or operator and the identifying mark assigned to each

welder or operator. This record shall be certjf¡ed by the fabricat¡on or erection Manufacturer and shall be

access¡ble to the insPector.

WELoED TANKS FoR OrL SToRAGE

9.4 ldent¡ficat¡on of Welded Jo¡nts

The welder or welding operator's identif¡caüon mark shall be hand- or machine-stamped adjacent to and at intervalsnot exceeding 1 m (3 ft) along the completed welds. ln l¡eu of stamping, a record may be kept that ¡dent¡f¡es thewelder or weld¡ng operator emdoyed for each welded joint; these records shall be access¡ble to the inspector. Roofplate welds and flange-to-nozzle-neck welds do not requ¡re welder identificat¡on.

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