PQR hardness P5A to Incoloy Alloy 800HT

[Pickaspot]

B31.3 code

Reviewing my PQR lab results I have some concern in regards to the hardness results in the P5A HAZ. The highest Vickers(HV) reading was 284 this is with no PWHT being performed. I referred to the toughness test results and referenced B31.3 to which they are acceptable.

I selected ErNiCr-3 as the filler material the highest Vickers(HV) in the weld metal was 190 which is great!

My question is the production weld is a 1/2" schedule 80 socket weld, should I consider PWHT due to this high HAZ reading or is this an acceptable HAZ hardness for P5A?

Thank you!

 

[metengr]

There is no reason to perform PWHT of a fillet weld for the above application. The 284 BHN is well within the peak hardness I would expect for a P-No 5A base material HAZ, like 2.25% Cr-1% Mo. Keep in mind you have low carbon in the Grade 22 (assuming) base material. All of this is in your favor for reasonable ductility of the weld region. I would perform a surface NDT (like wet MT or LPT) to ensure no cracks.