One thing that I think has been overlooked, is the correlation between the material thickness used during welding of the PQR and what will be qualified for the WPS. Use of 12" Sch80 (17.47mm wall) for the PQR would qualify a material thickness range of 10mm to 34.94mm (2T) for ASME Section IX qualifications (Table QW-451.1). For B31.3 applications, any production welding over 19mm would require PWHT. Therefore, w/o PWHT of the PQR the WPS could only be written for 10-19mm. With PWHT of the PQR the WPS could be written for 10-34.94mm, but PWHT would be required for all production welds made to this WPS.
Jon,
I don`t know in the USA, but down here in Brazil the inspection firm would send her inspector(s) to the pipe manufacturing plant to check the documentation and make a random measuring of the pipes.
As erection contractor or piping pre-fabricator, what I`d receive is a report signed by the inspector stating that the pipes are in conformity to the purchase order. The documentation remains in possess of the inspection firm.
Of course, if the pipe thickness is within the minimum and maximum tolerances, the inspector will sign the conformity, so, as I`ve said before, I`m not supposed to check again the thickness.
I thank you for your kind words on my person. Happy New Year for you too.
Giovanni S. Crisi