Hardfacing Overlay PWHT Requirements---- Urgent Please

[Tomy-Met]

Gents, Please advise

We have repaired (Cracks excavation & Weld overlay) disc seating of our HP Steam valve.
Valve material is 13CrMo-44 and overlay filler was Stellite-6, Preheat of 200C was maintained.

My Questions are;
Is there any adverse effect associated with PWHT after hardafcing overlay?
From Where should i take PWHT parameters? ASME B31.1? Any Special control measures to consider for such type of PWHT?

Thanks in advance.

 

[TGS4]

First, you need to ask yourself, what is the purpose of the PWHT? Are you trying to achieve a certain level of residual stresses, or it something else?

 

[Dhurjati Sen]

Dear Tomy-Met,

Normally, a new valve is procured in such cases. Repairs do not last long enough. Special electrodes come for stelliting. Follow the procedures as specified by the manufacturer. Did they ask for PWHT?

Regards.

DHURJATI SEN
Kolkata, India