Interpretation: IX-07-09
Subject: QW-401.3 and QW-403.6, Thickness Range Qualified for Impact Testing (2007 Edition)
Date Issued: May 1, 2008
File No: 08-576

Background: A welding procedure qualification was performed on a 1 in. (25 mm) thick test coupon. Tension and bend tests were performed on the 1 in. (25 mm) plate. A second welding procedure qualification was performed on a 0.24 in. (6 mm) plate and only impact testing was performed. All of the essential and supplementary essential variables remained the same except for the coupon thickness.

Question: May the above PQRs be used to support a WPS for materials requiring notch toughness with a qualified thickness range of 0.1875 in. (5 mm) to 2 in. (50 mm)?

Reply: Yes.

How can the thickness range for impact test qualified for 5 to 50 rather than 6 to 50?

Thats correct as statement.

Any clarifications on that?

Let us consider if the thickness of specimen is 8mm than that of 6mm then what will be the Qualified thickness ?
Is it 5 to 50 or 8 to 50?

Update in new standard, you may see QW-403.6: min. thickness qualification T or 5/8 "; or 1/2T if T less than 6 mm.

So, the second your quesion should be range from 8 to 50 mm.


Thanks bien

Minimum 2 PQRs to cover 8 to 50mm.