QW 403.6

[isaa]

Hi, uptill now I was under the impression that qualifying a PQR on 6mm T qualifues from 3mm to 12 as per qw 403.6.and there are few interpretations in support with this.

But in ASME IX 2015 addition there is an interpretation IX-15-03

Question:A welding procedure with impact testing was qualified using a test coupon of 6mmm. Does this qualify for 3mm to 12mm thicknes, since 6mm thickness is less than 1/4 inch (6.35mm)?

Reply: No; see Nonmandatory Appendix G.

Now this is something confusing. Please help

 

[david339933]

Appendix G deals with US Customary and SI Units. 1/4" is equivalent to 6mm....therefore T must be less than 6mm.

 

[merlin000]

When using ASME IX and we are requiring CVN testing. we go to B31.3 table 323.3.1 A5 where the thickness range is T/2 to T + 1/4 inch. And not the thickness range specified in ASME IX. So i think its correct if you qualified on 6mm then thickness range qualified would be 3mm to 12mm.

 

[merlin000]

Gents
Ref thickness range i have been informed you would need to qualify less than 6mm maybe 5.54mm