PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6 1

[bryancobb]

Doing a Low-Temp bath coil for Canada. MDMT = -50F. Code of Construction = ASME B31.3

I am trying to determine best test pieces to qualify for 2"Sch80 and 1"Sch80.
Pipe, Elbows, and Fittings are in P1/Gr1 and Flanges are in P1/Gr2, per ASME IX.
Impact toughness test are required. Double Bevel groove weld using GTAW on all passes due to small
size of pipe.

My questions are...
Q: Does the flange being in Group 2 require a group 2 material be joined to a Group 1 material for Tensiles, Bends, and Charpys?
It appears to me that QW-424 allows a test piece of 2 pieces of SA-333 Gr6 pipe and that would allow us to weld on flanges in production.
It will be much more costly if a weld neck flange is involved because of flange cost AND test specimen fabrication labor.

Q: Does anyone have a suggestion for a company to do the Lab Testing?
We have already used ATS for one round of tests on two SA-333 test pieces and the results were invalid because subsize specimens were
required and ATS had not applied the B31.3 reductions to Temperature and Energy. Now we have been talking with Ludwig Assoc., LTD. in
Alberta and they are saying a flange must be in the testing. This makes me question Ludwig's reliability since QW-424 seems to disagree.

Thanks in advance for any advice.

Bryan Cobb, ASME QC Representative

 

[bryancobb]

mrfailure,

I think the origin of the comments about testing labs were rooted in my original post where I disclosed that the first lab I used failed to decrease the MDMT per code, for the subsize test specimens.

 

[mrfailure]

We avoid the problem that happened with your test by providing a copy of the Code testing requirements to our technologists each time such a job comes in. I would like to think your experience is the exception in using test labs rather than the rule.