PWHT

[PipelineNewbie]

I'm an engineer but new in pipeline/piping Could you please help me how to identify those Pipe/WT that needs PWHT for B31.3,B31.1 and CSA Z662.

 

[racookpe1978]

Have you asked your boss? Read your company's requirements?

 

[casa903]

PWHT requirements are driven by either material/thickness requirement(refer Table 331.1.1 of ASME B31.3) or specific fluids (Sour/Amine/Caustic/MDEA..etc).

 

[LittleInch]

This is a prime case where a good read of the codes you mention will stand you in far better stead than just asking people, because you will then understand the sections and where it does and doesn't apply.

I don't know the CSA code, but the pipeline codes are different (generally thicker) than the plant piping codes for when you need PWHT

Generally the welding specification will also pick this up, but don't rely on it.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[weldstan]

Also note that the exemptions for PWHT of P-No.1 material in B31.1 2014 Edition have been considerably increased. I understand that B31.3 will follow B31.1 when its latest edition comes out.