Impact test exemptions for Duplex Stainless 1

[arcer]

Is anyone aware of impact test exemptions allowed by ASME Sec VIII, for Duplex Stainless steels, other than that described in UHA 51 (d)(3)?

 

[metengr]

No. I also reviewed the ASME code case subject index.

 

[arcer]

I wasn't able to find any either. Thanks for checking. It just seems a bit strange, that, for example, 5/8" thick S31803 operating at say, 120F, would require impact testing. Anyway, that's just my observation.
Again, thanks.

 

[mancini]

I have been involved in the same problem informed by Arcer, does anyone have any information if really it is necessary to have impact tests for the base material and welding procedure if it is used a duplex steel and the MDMT is 0 deg and thickness is more than 3/8" used in a pressure vessel, as informed in UHA 51 (d)(3)?

 

[mcguire]

The reason for the special toughness testing is the possibility of embrittling phases being present. Alpha prime and sigma can embrittle before they are evident by other inspection methods.

Michael McGuire

http://stainlesssteelforengineers.blogspot.com/