Samples in WPQ

By zrc Date 07-11-2005 08:21

While carrying out welding procdure qualification of ASME 335 P91(TIG+SMAW) for main steam pipe in power plant, is it need to take Charpy impact samples at the root of the weldment to include the TIG weld metal (ususally 2 pass, 6mm)? or just take samples at the outer side of the joints?
in China only samples at SMAW weld metal will be taken out, would you please tell me the situation in USA or Europe?
when PWHT at 760 degree from the outer side, the real temperature at the inner root will be 740 degree or lower due to the heat loss, how to garantee the impact toughness of the root weld metals at so low PWHT temperature? thank you very in advance!

By Bill Mc (**)

Date 07-13-2005 17:27

ASME sect. 9 states that Charpy impact tests shall be made when required by other Code Sections. The "other Code Section" that specified the notch toughness test is required to specify the location and orientation. What code is the steam pipe....is it an ANSI B31.1 system? Does this applicable code even require Charpy tests?

By zrc Date 07-17-2005 15:52

the code is ASME B31.1 because it is a steam pipe for power plant, it need enough impact energy to keep safty during hydro-test.