D1.1 prequalified

Date 12-21-2006 17:19

Didn't see anything in D1.1 Sec. 3 or its commentary concerning welding steel with CVN requirements.

Did find a paragraph in C-4.12.4.4, in the WELD METAL column, 1st paragraph, 3rd sentence; I hope this helps you

By HgTX

Date 12-21-2006 22:14

Are you sure what you read wasn't about CVN requirements for the base metal? Seems to me if CVN testing is required for the weld metal, the only way to get those is testing the weld, which means a qualification test.

Hg

By QCCWI

Date 12-22-2006 12:00

FEMA 350/353 and AISC 341-05 state you are required to weld using a filler metal that has been proven to pass the required CVN test (ft/lbs @ specified temp). Neither one of those books state you have to quality the WPS for CVN testing. If you are using a weld filler metal that has been proven by testing by the manufacturer (Lincoln, ESAB or whoever) and welding a prequalified joint configuration the WPS is prequalified.

The weld parameters (Volt,Apms, WFS) on all my WPS come from the spec sheets the manufacturer puts out. All I need is a COC from the manufacturer stating the weld filler metal I am using has satisfactory results according to FEMA 350/353 and AISC 341-05.

Why should my company have to perform a CVN test on a prequalified joint configuration using a weld filler metal that the manufacturer has already CVN tested with satisfactory results?

By pax23

Date 12-22-2006 15:10 Edited 01-08-2007 14:03

I do not think the code is crystal clear on this question, but I feel pretty confident that the following is the code's intent.

If you already have a prequalified WPS or are putting one together, and you need to establish CVN results for the WPS, then you need only run CVN tests. The logic behind this is the code already implies that we should be confident that the prequalified WPS will provide necessary weld strength, soundness, quality, etc. When CVNs are mandated by contract specs, this only implies that toughness shall be measured not the other properties which the code has already deemed unnecessary to verify through testing. Just because toughness is now an issue it does not mean our faith in the procedure to give acceptable strength, soundness, quality, etc. should be shaken.

Section 4.35.3 [editorially corrected reference] clearly states what must be done if an existing qualified WPS is applied to situations where CVNs are mandated. (1) You need only to do a test plate for CVNs. (2) You have to tighten the EV ranges on the existing WPS to include Table 4.6 variables. (3) You must revise or replace the original PQR and WPS taking into account the new test and Table 4.6.

There are always exceptions, 3.14(3) states if PWHT is required when toughness testing is also required then the WPS cannot be prequalified, that is you need to do a full test plate with CVNs, bends, tensiles, etc. Also Table 3.1, note b states that the allowable filler metals for certain base metals need to be tighten on prequalified WPS; you would NOT need to run a test for bends, tensiles, etc. but you would need to revise the prequalified WPS to tighten the filler metal requirements.

Short answer, just run your 3G up and be done with it.

By HgTX

Date 12-27-2006 20:06

4.35.2 in which edition?

Hg

By pax23

Date 01-03-2007 18:35

I am referring to the 2006 edition:

4.35.2 CVN test specimens shall be machined from the
same welded test assembly made to determine other weld
joint properties (see Figure 4.7, 4.8, 4.10, or 4.11).
Where the size of the welded test assemblies is not sufficient
to satisfy all the mechanical testing specimen requirements,
an additional welded test assembly shall be
performed. The CVN test specimens shall be machined
from the welded test assembly in which the tensile test
specimens are machined.

By HgTX

Date 01-05-2007 21:51

I'm not reading what you're reading into that. I see 4.35.2 merely as a how-to for machining the specimens. I don't think it says anything about what other tests are or are not required. If anything, it implies that the full complement of tests is performed, because it says "shall be machined from the same welded test assembly made to determine other weld joint properties".

Not that this answers the original question.

By pax23

Date 01-08-2007 14:03

My mistake. My reference should have been to 4.35.3.

4.35.3 When CVN testing is a requirement and a qualified
WPS exists which satisfies all requirements except
for CVN testing, it shall be necessary only to prepare an
additional test weldment with sufficient material to provide
the required CVN test specimens. The test plate
shall be welded using that WPS, which conforms to the
limits of Tables 4.1, 4.2, and 4.5, plus those supplementary
essential variables applicable only to CVN testing
(Table 4.6). A new or revised PQR shall be prepared and
a new or revised WPS written to accommodate the qualification
variables for CVN testing.

By HgTX

Date 01-08-2007 20:42

In that case I'm still not reading the same into that paragraph as you are. It says, "When...a qualified WPS exists..." So if you've already done a PQR without CVN testing and then someone wants CVN testing, you don't have to do a whole new PQR. But it doesn't address the case of an otherwise prequalified WPS with no PQR.

By pax23

Date 01-09-2007 18:31

I never said that it did. The code is SILENT on the question regarding prequalifed WPSs. The code is CLEAR on the question regarding qualified WPSs.

Now what? I have a question and the code does not give me a clear answer. Well, I could extrapolate from how the code handles a similar issue. I think there are parallels between the two. So I was not trying to say that 4.35.3 answers the question on prequalified WPSs, only that it gives us a guide to how to handle something that it does not address.

You work with these codes enough and you will find holes, things the code committee did not anticipate. You will also find things that you assume are holes but later find out that the code committee consciously decided not to address.

Well, you may say, "I have a question and I need an answer from the code". I say that the code is not there to answer every question; it is only there to do two things: (1) tell you what you must do and (2) tell you what you must not do. It is not there to tell you what you need not do. If the code included everything you need not do it would probably expand to 1000 pages.

In applications where toughness is required...
Does the code tell you that you need to run CVNs if you are applying an existing prequalified WPSs to the application? In my opinion, yes.
Does the code tell you that a prequalified WPSs cannot be used for these applications? In my opinion, no.

By CWI555

Date 01-20-2007 19:45

I believe you are correct hwen it comes to "what you need not do". However; there are many things that need to be done, that are not addressed. I have found assumptions in the code (ASME IX, D1.1, D1.3, NFPA, and others). It was explained to me by an ASME committee member that some things are just common sense. It was also explained to me that in todays legalistic society in America that more and more, if it's not specifically forbidden in a code it's allowed, no matter how much common sense says not to do it.

My two cents worth

By GRoberts (***)

Date 12-30-2006 06:00

It's taken me a while to get back to this issue, but I did a little more looking. I think D1.1:2004 section 2 summarizes it best- I don't get into section 2 that often, so it is easy to overlook. Take a look at paragraph 2.2.2. I think it is saying that the engineer should specify if weld metal classification by the manufacturer is enough, or if actual testing is requried.