PWHT Stainless Steel - Essential Varialble? 3

[rustbuster]

I am looking at doing PWHT (solution annealing) on 304H material to reverse the sensitized HAZ. Looking at QW-407 of AMSE Sec. IX I am interpreting that PWHT is not an essential variable for weld procedure and that an additional PQR is not required.

Is this interpretation correct?

 

[metengr]

rustbuster;
PWHT is considered an essential variable for welding processes. IF you omit PWHT from a WPS that was originally qualified with PWHT you need to re-qualify a procedure. If you have qualified a WPS for P-No. 8 base material with no PWHT and you decide to perform a solution anneal after welding this does not effect the original WPS/PQR.

Why? Because solution anneal is an optional fabrication step for restoration of corrosion resistance of the weld joint for this application, and does not impact the mechanical properties of the weld joint. This is why PWHT of P-No. 8 materials is neither recommended nor prohibited by construction codes.

 

[rustbuster]

Thank you sir, that was my assumption but I wanted some re-assurance.

And Merry Christmas to all...