Impact Testing

[Agnewt]

I have a weld procedure that was qualified and approved a few years ago WITHOUT impact testing. Since then we have welded a second test coupon (using the same procedure) and have had it tested again (tensile, bend tests) but this time WITH impact tests. Now my question is: What are the codes/rules regarding impact testing that was done after-the-fact? Can the results simply be "updated" or added to the existing WPS/PQR without having it recertified with TSSA? Or do i need to create an entirely new PQR using the results from the new coupon and have it sent out to be certified?

 

[Agnewt]

Further to my questions above, can you even use the results from two different samples in one single PQR, even if you have it recertified.

For example, Sample#1 was welded using WPS-X and was sent out for for tensile and bend tests, and Sample#2, also welded using WPS-X, but welded on a seperate date as a seperate piece, was sent out for impact testing.

All else being equal (same WPS, same thicknesses), can the results from the two seperate samples be combined onto one single PQR and sent out to be certified?

Does the PQR absolutely need to every single test result come from coupons from one single sample that was welded as one continuous weld?

 

[HgTX]

AWS D1.1 clause 4.35.3 explicitly allows welding a new plate for impact testing. What code are you working to?

Hg

Eng-Tips policies: faq731-376

 

[Agnewt]

Sorry I left that out, ASME IX is what I'm using.

 

[weldtek]

Agnewt,
As you evidently intend to do, a WPS may be supported by multiple PQR's. It sounds as though you performed tensiles and bends on the second coupon, and, if so, that isn't necessary to add impact qualification to an existing PQR.
Review QW 200 and the supplementary requirements for the process you are qualifying.

 

[weldtek]

Agnewt,
I should have added that using material for your supplementary test plate of identical thickness to the original test plate is not necessary and may not be desirable, depending on the range of thicknesses you want to qualify for.

 

[Agnewt]

Well the scenario is this: A customer we are dealing with has very strict constraints on which welding practices we can use to fabricate their orders, basically we are restricted to using only GTAW. In addition, a few of the items on their order are for low-temp applications and they require we use a welding procedure WITH impact testing to fabricate these items. The problem is the only WPS we currently have for GTAW was qualified and stamped WITHOUT impact testing. However, since that date, we have welded a second sample and had it tested, this time WITH impact testing as well as the usual bend/tensile tests. What I'm wondering is if we can add supplementary test results to an existing PQR that has already been approved and stamped? Or do I need to write up an entirely new PQR with the addition of the impact test results and have it recertified with TSSA?

QW-200.2(c) deals with changes made to a PQR. It states that "All changes to a PQR require recertification". But I haven't really made any changes per se. The second sample, the one that was impact tested, was welded using all the same variables as the original sample that was used for the PQR. I simply want to add supplementary test results.

 

[HgTX]

Check your code requirements for retests. If you'd run impact tests originally and if they would then have allowed welding a new plate for retesting, then surely the new plate ought to be allowed without a failed test beforehand.

Hg

Eng-Tips policies: faq731-376

 

[stanweld]

Since you performed complete testing and have established the heat input and other supplementary essential variables used in qualification, you have produced a separate PQR, which can be used to support your WPS. The WPS would have to be amended to address all supplemntary essential variable as well when impact testing is mandated for the work.