Post weld heat treatment of Alloy 625 welding?

[AarnoudO]

Dear all,

I am designing a pressure retaining cylinder made from two seperate pieces of Alloy 625. We are joining these two sections by welding.

Now I have become convinced that post weld heat treatment for this weld in not neccessary. (Suppliers datasheets of alloy 625 state that post weld heat treatment is not nessecary.)

However, I can not seem to find this in ASME IX and ASME B31.3

For SS316 (P-No 8) I can see in ASME B31.3 table 3321.1.1
that no post weld heat treatment is nessecary.

But for Alloy 625 (Inconel 625) I can find no reference.
P-No 43 does not appear in this table.

Can someone help me to locate where it says something about post weld heat treatment of alloy 625 in the ASME code?

Any help would be highly appreciated.

 

[metengr]

PWHT of nickel-base alloys is normally not required (see UNF-53 in ASME Section VIII, Div 1). Section IX deals with procedure and welder qualification. Please review ASME Section VIII, Div 1 Part UNF.

 

[metengr]

Correction; UNF-56.