Certs

By Lawrence (*****)

Date 08-06-2008 04:33

Milton,

Al is probably the best person to respond on this but I'll pitch in just this:

If you secure the PQR for your D17 work and it proves that you have also met all the criteria for D1.1 Section 4 (in every aspect) than it seems logical that you could produce a WPS for your structural D1 work.

By Milton Gravitt (***)

Date 08-06-2008 09:05 Edited 08-06-2008 21:03

We used and outside source to do all our testing and we where certified D17.1 and D1.1and AWS B2.1.
Al what do you think if you are certified for 4130 are you certified for A514 grade B steel without retesting.

By 803056

Date 08-07-2008 03:17

Unfortunately I would think the answer would be no.

4130 is an AISI designation indicating the alloy is a chrome moly steel with about 0.3% carbon. AISI does not list the mechanical properties, product form, state of heat treatment, etc. The A514 grade B has published mechanical properties as well as all the other information not provided for the 4130 alloy.

Let's look at the chemistry;

4130 A514 Gr B
carbon 0.27-0.34 0.12 - 0.21
Mn    0.35-0.6 0.7-1.0
Si    0.15-0.30    0.2-0.35
Ni
Cr 0.8-1.15 0.4-0.65
Mo    0.15-0.25 0.15-0.25
YS not spec    90-100ksi
TS not spec    100-130ksi
Elong not spec    17-18
CE    0.41 0.25

Chemistry: similar, but not the same. Mechanical properties: ? Carbon equivalency: I look at the difference in the carbon content and the CE of the two materials and in my mind the difference is significant.

Again, after looking at the numbers, I would not expect the engineer to agree to permit the qualification of one to be a substitute for qualifying the other.

Best regards - Al

By Milton Gravitt (***)

Date 08-07-2008 13:48

Thanks Al for your help.

By Lawrence (*****)

Date 08-08-2008 05:43 Edited 08-08-2008 05:48

Al,

I like your argument and wisdom...

But D17 is pretty generous in welder performance qualifications.

In the world of D17 the A514 is a "group I" metal and the 4130 is a "group IA" metal.

D17 Says something like...
Group Qualification. Qualification in a base metal group with a "B" designator also
qualifies base metals with the same Roman Numeral designator and an "A" designator. For
example, a welder or welding operator qualified using Base Metal Group IIIB material for the
test sample also qualifies for Base Metal Group IIIA.

So "technically" it appears that a PQR/performance qual for Group I (A514) also covers Group 1A (4130)

This observation in no way blesses the generation of a D1.1 WPS for 4130 from a A514 qual or visa versa, smiply by the merit of D17 allowing just exactly that... It's only a point of interest to consider when contrasting different codes.

By 803056

Date 08-09-2008 13:18 Edited 08-09-2008 13:25

I find it interesting that you looked at the question as one about performance qualification and I looked at it from a procedure qualification standpoint.

As for performance qualification, I believe the engineer would still have a problem because the base metal (AISI 4130) isn't included in the list of prequalified base metals.

The problem might have been avoided had the 4130 been purchased to an ASTM standard, but still there is the issue of the base metal being a listed base metal in D1.1 for either procedure or welder qualification.

I would think that in the grand scheme of things that if a welder can pass a test with the higher alloy, higher strength steel, he will be able to pass a test with a low strength steel. For the most part, AWS D1.1 follows that philosophy, but as always, the devil is in the details.

An alternative may have also been to refer to AWS B2.1 for the welder qualification. The material would fall into the M4 (P4) group (1 chrome 0.5 moly) while the A514 Gr B is a M11B (B2.1). Like ASME, AWS B2.1 would allow the welder to be qualified using a wide range of base metals meeting M1 through M11 groupings. Likewise, the F number of the filler metal could be compared. It is most likely going to fall into either a F4 or F6 groups. The welder would then be qualified for any of the filler metals in the F group. AWS D1.1 does have provisions for welders qualified in accordance with B2.1 to be accepted by AWS D1.1 (2004 is the one I looked at). There is a high probability that you can cross reference the 4130 with a UNS number that is listed in AWS B2.1 and work around the issue of welder qualification that way.

The A number isn't a consideration for the welder qualification, whereas it is for the procedure qualification. In this case, the A number of the filler metal may be different for the two base metals listed (assuming the procedures would not use the same filler metal for both base metals), so again the procedure would fall through the cracks.

Details, details, details. Are we dealing with procedure qualification or performance qualification? You may have hit the mark Lawrence and you've given me a reason to revisit my initial response.

Best regards - Al

By Milton Gravitt (***)

Date 08-10-2008 00:53 Edited 08-10-2008 00:57

Well we've taking test for two day counting today on the A514 grade b. I have taking the test for 4 sample for GMAW and two other welders has taking the GTAW. The planner on this job pick up the samples today to carry them to and out side source to be VT and MT and then cent to another company for all the mechanical testing.
I have read another post on the forum about stamping A514 can you steel stamp A514. What is your opinions.

By Milton Gravitt (***)

Date 08-23-2008 15:11

We got our test results back the other day on the A514 material some good and some bad news .We sent 8 tests out and past 6 out of the 8 all the GTAW past, I took 4 out of the 8 GMAW which 2 of them failed. I hated that I fail the two tests but did learn something. The test was a 4 inch wide by .250 thick cut on a 45 degree angle one side was beveled with a landing and with a .125 backing plate. I believe if I had feathered the landing down to nothing it would have a better chance of pasting. Thanks for everyone's help.
MG