QUALIFICATION OF WELDING PROCEDURES AND WELDERS

1.1    Welding Procedures
Welding procedures shall be in writing and shall be qualified in accordance with ASME Boiler and Pressure Vessel Code, Section IX. All welding procedures shall be identified by a unique number and shall be referenced on all applicable fabrication drawings.
These procedures shall include the following: Welding Procedure Specifications (WPS), Procedure Qualification Test Records (PQR), ranges of variables qualified, a weld map or description identifying which welding procedure will be used for each weld, method and extent of inspection. For piping, representative weld maps illustrating the applicable weld procedures are required. 

1.2    Qualification of Welding Procedures
The P-number (as defined in ASME Code, Section IX) shall be considered an essential variable for all welding processes. Materials having no P-numbers shall be qualified individually. Note that any changes in essential variables require.
Welding position shall be considered an essential variable for groove welds in all automatic welding processes. Note that welding position is an essential variable for welder qualification.
All welding consumables not listed in the ASME Code, Section II, Part C shall be individually qualified.
For submerged arc welding, brand name and grade of flux shall be considered an essential variable, together with changes in speed or heat input beyond the range qualified. The procedure qualification test record shall indicate the name of the manufacturer sand the trade name of the wire and flux used to qualify the procedure.
Postweld heat treatment (time and temperature) shall be considered an essential variable for P-3, P-4, P-5, and P-6 materials.
Welding procedure qualification impact testing of welds and heat-affected zones (HAZ) for ferritic materials is required at the minimum design temperature.
When impact testing is required, the Charpy V-notch impact values for parent material, weld metal and heat-affected zones shall not be less than those specified in ASME B31.3 for piping. The impact test shall be performed on the same type (ASTM or other similar specification) and grade of material as will be used in fabrication.
Procedure qualifications for weld overlay deposits shall include complete chemical analysis of the overlay, procedure qualification test record, and sample of the overlay. The procedure qualification tests shall include:
a.  Dye penetrant examination of the completed weld.
b. Side bend tests and longitudinal face bend tests for weld metal soundness. Cracks at specimen edges shall not be considered part of the examination.
The welding procedure qualification tests shall include hardness tests for the following quenched and tempered carbon steel, high-strength low-alloy (HSLA) steel, carbon-molybdenum (C-Mo), manganese-molybdenum (Mn-Mo), chromium-molybdenum (Cr-Mo) steels; martensitic stainless steels and other air-hardenable materials.
Procedure qualification tests for welding carbon steel shall also include a hardness survey if any of the following conditions exist:
a)   Submerged arc welding is performed with F8XX or higher flux designation
b) Shielded metal arc welding is performed with covered electrodes of E80XX or higher  classification
c) Job specifications or data sheets require a maximum specified hardness in the weld and /or heat-affected zone
d) Process conditions (wet hydrogen sulfide, amine, hydrogen fluride, and caustic) require production hardness testing
The  hardness  testing for welding procedure qualification shall be performed on the base metal, weld, and heat-affected zone with an instrument having an indentor nor larger than 1/16 inch   diameter  (such  as  Vickers 10  kg load,  Rockwell  B  and C). The hardness shall be reported as Brinell (BHN), Rockwell B or C, or Vickers (HV) equivalent numbers. Hardness  surveys shall be performed along two lines  parallel  to the outer  and inner surfaces of the weld and located approximately 0.08 inch below them (Figure 1). The type of hardness test instrument shall be reported and the test result shall meet the hardness requirement of 225 BHN (238 HV10, Rc 20) maximum.
For gas tungsten arc and gas metal arc welding, the qualification record shall include the composition and flowrate of the shielding gas and inert gas backing, when used.