Interpretations in Procedure Qualification Record

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.

(Figure can not be attached; left side plate 1" and right side plate 1.5", not tapered only beveled ends) 

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.

Question (3):  Does this test coupon qualify the WPS for both base metals of different P Numbers for a thickness range of 3/16” to 8”?

Reply (3):  No.  QW-202.4 requires both base metal thicknesses be in accordance with QW-451.1.  Base metal T₁  is qualified 3/16” to 2” and base metal T₂  is qualified 3/16” to 8”, except as permitted by QW-202.4(b)(1).

QW 202.4 interpretations :

Interpretation: IX-95-12

Subject:            QW-202.4, Dissimilar Base Metal Thicknesses

Date Issued:     March 17, 1995

File No:            95-027

Question:  Does QW-202.4 include butt joints and corner joints when joining dissimilar base metal thicknesses when prepared with a groove?

Reply:  Yes. 

Interpretation: IX-98-20R

Subject:            QW-202.4(b), Dissimilar Base Metal Thickness

Date Issued:     June 8, 2000

File No:            99-539

Question:  When welding a corner joint with dissimilar base metal thickness, the thickness of both members must be within the qualified thickness range of the WPS(s) being used.  How is the thickness for the thicker member defined in sketches (a), (b) and (c) below?

Reply:  For sketch (a), the thicker of T or t_s.  For sketch (b), the thicker of T or t_s.  For sketch (c), the thicker of flange a or hub b.

(Figures can not be attached)

Interpretation: IX-01-19

Subject:            QW-202.4(b), Dissimilar Base Metal Thickness

Date Issued:     December 18, 2001

File No:            01-811

Question:  Does QW-202.4(b) permit the maximum weld deposit thickness limit to be extended beyond the limit specified in QW-451.1?

Reply:  No.  QW-202.4 applies only to the base metal thickness limits.

Interpretation: IX-01-23

Subject:            QW-202.4, Dissimilar Base Metal Thicknesses

Date Issued:     March 11, 2002

File No:            01-789

Question:  A WPS is qualified to weld base material from 1.6 mm to 20 mm.  May that WPS be used for welding a part 30 mm thick that has been tapered to 15 mm thick to another 15 mm part?

Reply:  Yes.

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 P-Number material and consisting of two plates of different thicknesses are welded together, where the thicker of the two plates (T₂ = 1-1/2” thick) has been tapered on a 4:1 taper down to the thinner plate thickness (T₁ = 1” thick).

Question (1):  Does this test coupon qualify the WPS for a base metal thickness range of 3/16” to 8”?

Reply (1):  See Interpretation IX-86-43, Question (2).