Why PWHT holding time has no range?
Why PWHT holding time has no range?
(OP)
Please refer to ASME Section 1 Table PW-39-1 to 13 or ASME Section VIII Table UCS-56. There is only minimum holding time for PWHT requirement. I don't see a re-qualification requirement when the holding time exceeds in a disproportionate manner....actually it happened - the contractor cooked the metal for almost 13 hours! Of course material properties deteriorated particularly notch toughness. My fundamental question: What is the rationale behind not specifying a range or limit on holding time for the PWHT? Is this again a case of common sense, engineering judgement, or due diligence? We need to draw a line somewhere.....





RE: Why PWHT holding time has no range?
You have handled the nonconformance correctly. The Code cannot prevent mishaps; this is why you are required to have descriptive nonconformance processes and method of disposition in your Quality Manual.
RE: Why PWHT holding time has no range?
RE: Why PWHT holding time has no range?
Did I miss something?
Best regards - Al
RE: Why PWHT holding time has no range?
You are correct if impact toughness is mandated. QW-407.2 is a Supplementary Essential variable. Otherwise it does not apply. QW-407.9 limits on time at temperature applies for corrosion resistant weld overlays.
RE: Why PWHT holding time has no range?
RE: Why PWHT holding time has no range?