American Welding Society Forum
ASME IX figure QW-202.1 allows additional test specimens to be removed from a procedure qualification test coupon in place of a failed specimen when other factors are in play. Without influencing anyone’s reply with my own thoughts and interpretation of QW-202.1, I will ask this question. If a single bend test specimen is deemed unacceptable out of the 4 needed, how many additional specimens are needed to replace the failed specimen? (Keeping in mind QW-451)
I only see the need for 1. I do not see where QW-451 comes into play.
The code seems pretty clear on this in my mind if the requirements of the paragraph are followed.
The reason I mention QW-451 is to note that 4 bend specimens is the amount needed and that there is no mention in QW-451 of the amount needed other than 4 bends. The way I’m Interpreting the Scenario I originally posted about is that an additional bend specimen, meaning 1, would be called for and allowed as long as the welding parameters weren’t at fault, to be bent in place of the failed specimen. If the additional bend specimen passes, then the guided bend test portion of the procedure qualification test is considered acceptable and is given a passing grade due to the Criteria of four bends being met. I was recently told by the lab that the one failed bend specimen warranted two additional bend specimens to be of acceptance in order to pass the guided bend portion of the test. Now if you go by that assumption, that would mean that you would need five Bend specimens total to qualify a procedure qualification record and four bends is now Irrelevant. This is where QW-451 is of value in my opinion. 4 is the magic number. Short and sweet, I feel that the lab is creating there own guidelines when following QW-202.1. Ask yourself this? Why stop at 2 bends? Why not 10 additional bends? ASME IX makes no mention of a “two for one”. Anyhow, that’s my thoughts on the matter. Can someone enlighten me to if there is such wording in ASME IX backing the stance that the lab has taken in this matter?
They may be confusing procedure qualification with welder qualification (although I do not use bend testing so unsure of requirements).
To save yourself and others from wasting time looking for the answers just ask the lab - where is the 2 for 1 noted in ASME IX ?
QW-202 TYPE OF TESTS REQUIRED
QW-202.1 Mechanical Tests. The type and number
of test specimens that shall be tested to qualify a groove
weld procedure are given in QW-451, and shall be removed
in a manner similar to that shown in Figures
QW-463.1(a) through QW-463.1(f). If any test specimen
required by QW-451 fails to meet the applicable acceptance
criteria, the test coupon shall be considered as
When it can be determined that the cause of failure is
not related to welding parameters, another test coupon
may be welded using identical welding parameters.
Alternatively, if adequate material of the original test
coupon exists, additional test specimens may be removed
as close as practicable to the original specimen location to
replace the failed test specimens.
If only 1 failed then only 1 is required
Believe me when I say this, I did just that! They would not budge an inch in their stance on the matter. It led to a big discussion, and it goes without saying, turned into an argument. They could not produce the “2 for 1” any where in the code that they were hanging their hat on but yet still chose to follow their OWN beliefs. I ended up talking to a few other labs that we have used in the past and they always follow “1 for 1” when the situation arises. This lab that’s in question is global and by no means a small or new lab. I just don’t agree with their stance on the matter. I wanted to see what other people felt on the topic. Thanks for sharing.
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