Dear group Members,
I would need ur valuable advise on can we use A193 B7 and A 193 2H as NACE bolts or I have to use the ones which end with M? (A193 B7M , or A 193 2HM)
gg: To ascertain whether you need to use "NACE" Bolting (eg. B7M/2HM), you need to establish whether the bolting would be exposed to H2S fluid/containing environment/ If so, it you next need to determine if the pressure in this environment is within the "Particle Pressure" prescribed to require such bolting. Yiu will see most PRV manufacturers offer their different levels of NACE certification (1. trim/initial wetted parts only 2. 1+ all other wetted parts when valve opens 3. 2 + external parts like bolting). You also need to get your client to understand that he is responsible for material selection acc to NACE. I have found NACE bolting requirement to be rare, but always tell the customer what he is getting.
Per ISO-4126, only the term Safety Valve is used regardless of application or design.