PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
(OP)
hello all,
I meet a case with dissimilar weld joint 9Cr with 310 austenitic SS
I found two approved WPS as follow:
• WPS no.1 filler metal is NiCr-3 with no PWHT (which mean the residual stress in the 9cr will not be eliminated).
• WPS no.2 filler metal is NiCr-3 but PWHT is required (which mean the austenitic SS will susceptible to sensitization).
I take my decision to follow WPS no.2 and perform PWHT at 720 C with 2hr holding time.
After PWHT I perform PMI on the 310 SS side HAZ which showed that the Cr percentage had been reduced from 24% to 18%
If I follow the correct procedure or there is any better procedure to follow.





RE: PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
RE: PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
RE: PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
RE: PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
Whereas B31.1, B31.3 require PWHT for the weld, why are you considering without PWHT? If this is a repair to an existing system, the Owner may option out of PWHT. Lastly is this P91 or P9 alloy?
RE: PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
That means after buttering you must also use Inco 182 in any case.
Regards - Juergen
RE: PWHT for dissimilar weld joint 9Cr with 310 austenitic SS
Finally the correct action to weld using inconil electrode followed by PWHT.
But what is your idea about the decrease of Cr percentage in the SS after PWHT.
RE: PWHT for dissimilar weld joint 9Cr with 310 austenitic SS