sPWHT on normal CS steel in Pressure Vessels
sPWHT on normal CS steel in Pressure Vessels
(OP)
Hi All,
we have a pending order with an US Oil Major which contains of:
Seamless Pipes in A106 (thickness<19mm)
Plates in A516 gr70 (t>19mm)
Flanges in A105 and A350 LF2
Forged Nozzles in A105 and A350 LF2
The materials are needed for a pressure vessel.
After some weeks they come back to us asking for a simulated post weld heat treatment on all materials.
This sound strange to me. As far as I know ASME does not require a PWHT for such materials. So why a sWPHT.
My experience/feeling with steel in oil and gas tells me this request is invalid, but since I am not an engineer I cannot find correct literature to support this.
Or am I mistaken and is the sPWHT a valid request?
thanks,
Martin
we have a pending order with an US Oil Major which contains of:
Seamless Pipes in A106 (thickness<19mm)
Plates in A516 gr70 (t>19mm)
Flanges in A105 and A350 LF2
Forged Nozzles in A105 and A350 LF2
The materials are needed for a pressure vessel.
After some weeks they come back to us asking for a simulated post weld heat treatment on all materials.
This sound strange to me. As far as I know ASME does not require a PWHT for such materials. So why a sWPHT.
My experience/feeling with steel in oil and gas tells me this request is invalid, but since I am not an engineer I cannot find correct literature to support this.
Or am I mistaken and is the sPWHT a valid request?
thanks,
Martin





RE: sPWHT on normal CS steel in Pressure Vessels
Steve Jones
Corrosion Management Consultant
http://www.linkedin.com/pub/8/83b/b04
All answers are personal opinions only and are in no way connected with any employer.
RE: sPWHT on normal CS steel in Pressure Vessels
RE: sPWHT on normal CS steel in Pressure Vessels
Thanks,
Ehzin
RE: sPWHT on normal CS steel in Pressure Vessels
RE: sPWHT on normal CS steel in Pressure Vessels
Regards
r6155
RE: sPWHT on normal CS steel in Pressure Vessels
Their request, regardless of "client requests above Code minimum" itself makes little sense phrased that way.
Recommend strongly that t hey be asked to clarify exactly what a simulated PWHT analysis is, on material not yet welded.
RE: sPWHT on normal CS steel in Pressure Vessels
RE: sPWHT on normal CS steel in Pressure Vessels
RE: sPWHT on normal CS steel in Pressure Vessels
Either way, sometimes (not often) vessels within a refinery can get repurposed from a service that doesn't require PWHT to a service that does require PWHT.
RE: sPWHT on normal CS steel in Pressure Vessels
Interesting second statement.....how is a vessel able to undergo PWHT when the welds are not qualified as such?
RE: sPWHT on normal CS steel in Pressure Vessels
Steve Jones
Corrosion Management Consultant
http://www.linkedin.com/pub/8/83b/b04
All answers are personal opinions only and are in no way connected with any employer.
RE: sPWHT on normal CS steel in Pressure Vessels
RE: sPWHT on normal CS steel in Pressure Vessels
By ensuring it was welded with dual qualified WPSs - with & without PWHT.
RE: sPWHT on normal CS steel in Pressure Vessels
RE: sPWHT on normal CS steel in Pressure Vessels
I'm just trying to provide the OP some reasoning why his client is requesting sPWHT.
1. The vessel will get PWHT.
2. The end user is planning for future PWHT.
3. Could be other reasons I'm not aware of.