This will depend on contractual arrangements between client and fabricator and/or the application and welding codes that are specified.
Qualification Standard for Welding & Brazing Procedures, Welders, Brazers, and Welding and Brazing Operators
Para. QW-100.1 states:
'Any WPSs used by a manufacturer or contractor that will have responsible operational control of production welding shall be a WPS that has been qualified by that manufacturer or contractor in accordance with Article II, or it shall be an AWS Standard Welding Procedure Specification (SWPS) listed in Appendix E and adopted by that manufacturer or contractor in accordance with Article V.'
BS EN ISO 15607
Specification and qualification of welding procedures for metallic materials - General rules
Para. 6.1 states:
'The manufacturer shall prepare a pWPS and shall ensure that it is applicable for the actual production, using experience from previous productions and the general fund of knowledge of welding technology. Each pWPS shall be used as a basis for establishment of WPQR qualified according to one of the test methods listed in Table 2.'
There are two methods given in Table 2 that allow welding procedure qualification to effectively be carried out by an organisation other than the manufacturer/fabricator.
One of the listed methods is based on tested welding consumables (tests carried out by a consumable manufacturer) and BS EN ISO 15610 gives details of how a consumable manufacturer's test data can be used to generate a qualified WPS.
The other listed method is by use of a standard welding procedure (a procedure based on welding procedure qualification tests performed by another organisation) and BS EN ISO 15612 gives details of how the parameters from a standard welding procedure can be used to generate a qualified WPS.
Structural Welding Code - Steel
Section 4.2.1 states:
'Except for prequalified WPSs in conformance with Section 3, a WPS for use in production welding shall be qualified in conformance with Clause 4, Part B. Properly documented evidence of previous WPS qualification may be used.
Section 126.96.36.199 states:
'Each manufacturer or Contractor shall conduct tests required by this code to qualify the WPS'.
Section 3.1 states:
'Prequalification of WPSs shall be defined as exempt from WPS qualification testing required in Clause 4'.
In order for a WPS to be prequalified, conformance is necessary with all the applicable requirements of Section 3 of the code.
Annex Q lists all the provisions that need to be included in a prequalified WPS and which should be addressed in the fabricator's or Contractor's welding program.