See Table UCS-56 against the P.No. of your material. For P.No. 1 materials, the minimum thickness requiring PWHT is 38mm. You may see for others in the table mentioned.
the material is ASTM A516 Gr.70 n i've gone through the code if the minimum thickness is 38mm then y does the table UCS-56 say the heat treatment for thickness upto 2inch also????
That's depend upon the design specifications issue by the designer. Code explicitly mentions "The exemptions provided in Table UCS-56 or Table UCS-56.1 are not permitted when postweld heat treatment is a service requirement"
ASME - Heat Treatment
Re: ASME - Heat Treatment
