January 2013

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 T is qualified 3/16” to 2” and base metal T 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 ts.  For sketch (b), the thicker of T or ts.  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).


We need to know the way of calculation temperature reduction when we use sub size specimen.

Problem:

We have tested an A333 Gr.6 (4" pipe-6.3 mm thickness). Laboratory used a sub size specimen (55*5*10) and tested it at -48c. test temperature of A 333 Gr.6 is -45C (3 degree Celsius cooler temperature) Unfortunately absorbed energy was low and the test was failed. We see a clause in standard (SA-333/SA-333M) which described that:

" 14.1.2) When sub size Charpy impact specimens are used and the width along the notch is less than 80% of the actual wall thickness of the original material "
Is this clause applicable for this case??????
Really we don't know which one is correct?

  • (5/6.3) * 100 = 79% then we should not apply the above mentioned clause and we shall calculate reduction temperature and test my sample in cooler temperature(-45 + -3 = -48).
  • (10/6.3) * 100 = 159% then we should not apply the above-mentioned clause and no need to reduce temperature and test my sample in MDMT(-45).


Whether Grinding or filling is allowed on the Final pass (on capping) for Welder performance qualification test (WPQT) for Plate or Pipe. Since qualification is done based on ASME Sec IX, so need reference only as per ASME Sec IX.

ASME Sec 9 - QW194, which only mentions the Complete joint penetration for visual examination for WPQT. But it is not more specific in case of Grinding or filling and also some other (acceptable limits?) parameters like Reinforcement, undercut, underfill, etc..

MKRdezign

Contact Form

Name

Email *

Message *

Powered by Blogger.
Javascript DisablePlease Enable Javascript To See All Widget