Advice on PWHT of DSS

[paavainathan]

Hi ,
Can any one advise me on what basis the PWHT is required for DSS weld joints. Is there any guideline to go for PWHT for DSS welding.

ASME B 31.3 syas neither required not prohibited .

 

[racookpe1978]

Please specify your DSS term more exactly. (Stainless steel obviously, but I've got to admit I don;t recognize your "D" term.)

 

[rneill]

Duplex Stainless Steel, probably one of the following grades but best for nikilkanna to clarify ... S31803, S32205, S32507, etc.

Unfortunately, I have no experience with PWHT of Duplex so can't comment on the question itself. I know that PWHT of regular austenitic stainless steel is controversial and that many feel the disadvantages of PWHT will outweigh the benefits with that material. Just don't know on the duplexes ...

 

[metengr]

Duplex stainless steel alloys are not formulated to be exposed to elevated temperature service (above 600 deg F), and this includes exposure to PWHT.

 

[SJones]

Any useful PWHT would have to be a full solution and quench. Not very practical in a large number of applications. PWHT would generally only be invoked to restore the correct phase balance or remove any undesirable microstructure.

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[paavainathan]

Thank for all replies.
DSS Duplex Stainless steel of UNS NO 31803 and 32607(25%Cr Super Duplex Stainless steel)which we are using in sour service with Service temperature min 5 and max 82 Deg Celsius.
the Welding using GTAW process.the material is in solution annealed condition.My doudt is whether we need solution ammealing after welding.any guideline to apply PWHT