Dissimilar Thickness Test Coupon PQR as Per ASME Sec IX.

[Ishack]

Does ASME Sec IX allows to use dissimilar thickness test coupon for Procedure qualification (PQR)?. As per QW 202.4, it talks about the production dissimilar thickness only.

As per my understanding, ASME sec IX doesn't address the test coupon thickness configuration and it is worthless in doing test in dissimilar thickness as it covers thickness range (weld metal deposit thick and base material thick) based on the least thickness due to the limitations imposed on the tensile test coupon requirements QW-151 and QW-462.

But the below interpretation is confusing,

Subject: QW-451.1, Procedure Qualification Thickness Limits and Test Specimens and
QW-202.4, Dissimilar Base Metal Thicknesses
Date Issued: December 22, 2004
File No: 04-599

Background: A procedure qualification test coupon using the same or different P-Number materials and consisting of two plates of different thicknesses, T2 = 1-1/2” thick and T1 = 1” thick welded with a single process. The thicknesses meet on the same plane with neither plate being tapered. The joint is welded in accordance with the sketch below.

Question (2): Does this test coupon qualify the WPS for both base metals for a thickness range of 3/16” to 8” on both sides of the weld joint?

Reply (2): Yes.
Dissimilar Thickness Test Coupon PQR as Per ASME Sec IX.

 

[metengr]

If you have the 2017 Edition of ASME Section IX, re-read QW-202.4

WPS
qualified on groove welds shall be applicable for production welds between dissimilar base metal thicknesses provided:

The above means you use a WPS qualified for groove welds for dissimilar base metal thickness applicable in production welds. WPS need to be qualified for production welds.... You have the conditions which apply in QW-202.4 (a) (b) 1 and 2.