ASME B31.1 - PWHT requirement issue
ASME B31.1 - PWHT requirement issue
(OP)
I'm trying to weld an angle valve P5a to an inlet material p5a and outlet material p4. Given the pipe are both DN40 Sch xxs, do I need to do PWHT?
According to asme b31.1, PWHT is not mandatory if the nominal material thickness is 13mm or less.
And also can anyone explain what does it mean by (A)(2) and (A)(3) in the below quote:
'(2)attachment welds for non-load-carrying attachments provided in addition to (A)(2) and (A)(3) above:'
What does it mean non-load-carrying attachment?
Thank you
According to asme b31.1, PWHT is not mandatory if the nominal material thickness is 13mm or less.
And also can anyone explain what does it mean by (A)(2) and (A)(3) in the below quote:
'(2)attachment welds for non-load-carrying attachments provided in addition to (A)(2) and (A)(3) above:'
What does it mean non-load-carrying attachment?
Thank you





RE: ASME B31.1 - PWHT requirement issue
Non load carrying parts are non-pressure parts.
RE: ASME B31.1 - PWHT requirement issue
RE: ASME B31.1 - PWHT requirement issue
RE: ASME B31.1 - PWHT requirement issue
Exactly. However, proper preheat and preheat maintenance are critical - once the weld has been started, do not allow the welder to take a break. It needs to be finished in 'one sitting'. And wrapping the finished weld with insulation to slow the cooling is a very good idea.