ASME B31.3-Impact testing requirements

[Thuhuongengineer]

Hi everybody,
Refer table 323.3.1 ASME B31.3, Number of test pieces for CVN test requirement that: "One piece, thickness T, for each range of (a) One piece from each lot of material in each material thickness from T/2 to T + 6 mm specification and grade including heat treat(1⁄4 in.)" It mean that when we qualify welding procedure range thickness aplly for WPS: T/2 to T+6, correct or not.

But refer QW-403.6 anf QW-451 ASME IX Max range thickness apply for WPS is 2T.

Summary, if CVN require Max range thickness 2T or T+6 ?

 

[stanweld]

B31.3 trumps ASME IX except when T + 6mm is > 2T or T/2 is < the minimum thickness qualified per ASME IX (not very likely).

 

[Thuhuongengineer]

any answer?

 

[DekDee]

Stanweld has answered your question.
The fabrication code (B31.3) takes precedence over ASME IX so it is T + 6 mm,
Regards,
Shane