Stabilize annealing 347H Stainless steel
Stabilize annealing 347H Stainless steel
(OP)
After welding 347H pipe, we performed stabilizing annealing at 900°C for 4 hours followed by rapid cool with forced air.
Our client wants us to perform a hardness test but I do not think it is necessary because the stabilizing annealing is performed to improved the corrosion resistance and not for reducing the hardness. Design code is B31.3.
Please advise if a hardness testing is necessary? Many thanks.
Our client wants us to perform a hardness test but I do not think it is necessary because the stabilizing annealing is performed to improved the corrosion resistance and not for reducing the hardness. Design code is B31.3.
Please advise if a hardness testing is necessary? Many thanks.





RE: Stabilize annealing 347H Stainless steel
I saw that in ASME B31.3-2014 edition they took out the table with the requirements for the hardness test, so you don't have any reference. (maybe in the client specifications you can find something).
Do you have any supplementary requirements, such as NACE?
RE: Stabilize annealing 347H Stainless steel
RE: Stabilize annealing 347H Stainless steel
No, there is no NACE requirement. The requirement for hardness test comes from client's specification which vaguely says that hardness testing shall be conducted following the completion of all PWHT.
RE: Stabilize annealing 347H Stainless steel
RE: Stabilize annealing 347H Stainless steel
RE: Stabilize annealing 347H Stainless steel
I suppose you can try also with a TQ, if you don't wanna do it.
RE: Stabilize annealing 347H Stainless steel
RE: Stabilize annealing 347H Stainless steel
Perhaps another case of "a little knowledge is a dangerous thing".
"If you don't have time to do the job right the first time, when are you going to find time to repair it?"
RE: Stabilize annealing 347H Stainless steel
Stabilizing Anneal is generally recommended to mitigate the effects of Polythinic Acid SCC(PTASCC) in refining environments. Susceptibility to PASCC can be determined by laboratory IGC corrosion testing according to ASTM A262 Practice C or Practice E. Many Oil and Gas refiners (Example Aramco) ask for this requirements(Ptractice C) in their operating specifications (SABP-A-001.)
NACE SP170-2012, elaborates on chemistry control , and operating practices, not on testing methods to detect the susceptibility of cracking (as above).
FYI ASTM A312, calls for IGC Practice E under supplementary clauses.
In your case the could be a supplementary requirement( which could be clarified by client only). However the emphasis should been on the IGC testing methods as above.
Thanks.
Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist
Ontario,Canada.
ca.linkedin.com/pub/pradip-goswami/5/985/299
All provided answer are personal opinions or personal judgements only. It's not connected with any employers by any means.