PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
(OP)
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





RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
Yes, because for impact qualification the group number is a supplementary essential variable for the GTAW process (see Qw-256). This means for procedure qualification for impact, group number is treated as an essential variable (see QW-200). Flange material is not needed, only a base material with Group 2 designation can be used.
Discuss the above with the last lab you mentioned. Most mechanical testing labs have limited ASME B&PV Code expertise and they only do what the client requires. So, review Section IX and tell the lab what you want.
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
Would that qualify to weld pipe less than 24" O.D.?
I though a plate qualification only applied to large-bore 24" and up?
Bryan
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
Do tensiles and bends from 2 pieces of 2" Sch80 SA-333 Gr6 pipe. That fulfills the requirement for welding pipe less than 24" diameter?
Then do Charpy specimens from 3/8" plate of a piece of SA-516 Gr70 and a piece of SA-516 Gr60, which would fulfill the impact toughness requirement?
AM I CORRECTLY GETTING WHAT YOU ARE SAYING?
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
Would appreciate some feedback on this subject.
I work predominantly in LNG (low temp) and I have worked as Clients Rep for some major companies including US companies Chevron, Fluor, KBR and I have reviewed numerous PQR/WPSs from other large US companies - CB&I and Bechtel.
They have all qualified their PQRs with SA 333 pipe welded to SA 350 flanges.
Have they mis-interpreted QW 403.5 or do they not have access to the materials Stanweld mentioned ?
Your thoughts greatly appreciated,
Regards,
Kiwi
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
Pipe spool fabricators most often qualify on piping materials.
I have had, on occasion, to mandate additional impact test qualification on production pipe material when I knew that the heat inputs specified were in no way indicative of that actually being used. In those cases, I or my designee witnessed and recorded the parameters during procedure qualifications.
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
Please give me a "NORMAL" heat input on a GTAW only test on 2"Sch80 at a 600# WN Flange for this material.
(A*V*60)/(TravelSpeed "/Min) = Joules/Min of HeatInput
Assume 2"/Min Travel Speed Looking at the settings on the machine after a pipe to flange weld, it looks like they are using 90A and 15V ...Does 40,500 J/Min. sound about right?
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
While subsize specimens will be required, be sure not to misinterpret the requirements for temperature reduction under ASME B31.3 and ASME VIII, Div.1.
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
He seems to really know what he is talking about.
Thanks to all who commented to help me get a clearer picture of more welding in areas I'm not familiar with.
Bryan
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
I can provide full service welding engineering consulting and testing for less than Alberta rates.
GRS
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
That's what the metallurgists in NC said too, and they sent us on a wild goose chase! :)
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
Weld parameter measurement is best not left to welders, foremen and generic QC personnel who often don't know why it is necessary and can be quite casual about the exercise. In short they should be expertly monitored (so poop does not accumulate, figuratively speaking).
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
When running PQRs on thicknesses that may yield subsize Charpys, choose your base metal thickness carefully (mill it to optimum if necessary), make sure your joint alignment is perfect, and control angular distortion if qualifying on plate. You don't want to increase the temperature penalty by unnecessary extra machining. When your MDMT is -50 on carbon steel, there's not a lot of margin.
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6
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.
RE: PQR for SA-333 Gr6, SA-350-LF2 cl1, SA-420-WPL6