GROUP NO -ASME Sec IX of BPVC

[GD2]

Can someone define what are Group No 1, 2 and 3 that is subset of P-Nos? I am aware that the Group numbers are assigned when WPS requires impact testing.
But what is actually the difference between Gr 1, Gr 2 and Gr 3 and where is it described in ASME BPVC?

GDD
Canada

 

[IdanPV]

The Base Metal P-Numbers and Group Numbers are shown on ASME IX, Table QW/QB-422.
Change in the Group Number is define as a Supplementary Essential Variables.
Those variables become additional essential variable in situation were the referencing code, requires toughness testing. See QG-105.3 and QW-401.1.
The welding variables are shown on QW-250, note that each welding process has it's own table.

The change in the material group number is due to variations in chemical composition. Materials of different grades within the same specification may have different group numbers.

 

[weldstan]

The difference is primarily minimum UTS/MYS and allowable C and Mn contents.

 

[Jarbas Padua]

Can someone inform in which standard/norm can be found the manufacturing undertolerance and overtolerance for A-516-70 plates

 

[Geoff13]

Can someone inform in which standard/norm can be found the manufacturing undertolerance and overtolerance for A-516-70 plates

If you have an unrelated question you need to start a new thread. Or a simple search of the existing threads would likely find you the answer.

 

[GD2]

Thank you all for your responses.

GDD
Canada