F4 covers all F groups below...

Date 10-21-2016 21:07

Before you tell be to find the answer to this in other forum entries, been there done that... and i know what is generally accepted, however, what if you have conflicting information i.e:

Its generally accepted that If your qualified in F4 that your qualified in F's3,2,and 1, but does it?

Im refering to Table 4.5 in AWS D1.1, its the PQR Essential Variable Changes Requiring WPS Requalification, under Filler metal "2) Change from low-hydrogen to nonlow-hydrogen SMAW electrode".

The PQR is quoted in the WPS, we weld to the WPS... but what of restrictions (essential variables) that would disqualify one PQR being used if you qualify it in Low Hydrogen... it only covers Low Hydrogen, it would require a re write for any other F Group WPS... am i reading that right?

And if i am... wouldnt that throw out the whole idea of at least F4 covering F's 3,2 and 1? Or at least wouldnt that require a seperate wps for each... which would be essentially the same as saying two Certs...

Comments please

By 803056

Date 10-22-2016 02:20

You are confusing the qualification of a WPS with the qualification of the welder.

Al

By welderbrent (*****)

Date 10-22-2016 02:28

Well, Al beat me to it.

The F grouping chain you refer to is for welder qualification. It does not apply to Procedure Qualifications.

Once a welder qualifies to an F4 electrode he is then qualified to weld with any of the lower F number electrodes if that is what a procedure was qualified to.

Change the electrode F group for a procedure and it must be requalified. But the welder is still qualified to weld to the new WPS from the PQR.

He Is In Control, Have a Great Day, Brent

By MalRD

Date 10-22-2016 16:10

But we would still need two PQR's right? One for Low Hydrogen and the other for Non Low Hydrogen as there is a distinct exception in the essential variables... If that is the case, then what of the prequalified joints in D1.1? Should i assume because of the generally accepted "any F group lower" rule that they are qualified with 2 PQR's... Is that a safe statement? I see 10 or 12 PQR's listed on some of the SWPS's, so i assume it is logical to assume.

By welderbrent (*****)

Date 10-22-2016 16:55

You are mixing apples with kiwis now. Apples with oranges: welder qual with Welding procedure; Apples with kiwis: joints with electrodes.

If you are using a Prequalified joint from Clause 3 and a low hydrogen electrode then you don't need a PQR because all is good to go and the qualified welder is good to weld it.

If you are using a Prequalified joint but a NON low hydrogen electrode then you need a PQR approved from which you will write a WPS and the qualified welder is still good to weld it with the correct paperwork.

If you are using a Non qualified joint with a low hydrogen electrode then you need a PQR approved from which you will write a WPS and the qualified welder is still good to weld it once all the paperwork is correct.

If you are using a Non qualified joint and a non low hydrogen electrode you need a PQR, the WPS from it, and the welder is good to go.

Now, I am referring to any welder already qualified to the Clause 4 Welder Performance testing in D1.1. We know, that the welder who runs the test to get the PQR through testing is specifically qualified for THAT PQR arrangement in addition to his earlier credentials as a qualified welder. And, if you wanted to prove that ALL your welders can perform the welding of that job correctly you can also administer a welding test just for them to do so but it isn't needed unless you or the customer decide that it is.

One more thing, for their purposes and for certain jobs and codes, it will take multiple PQR's to establish enough information and testing to write one WPS. That has nothing to do with the conversation here. As usual, somethings just complicate simple procedures.

He Is In Control, Have a Great Day, Brent

By MalRD

Date 10-22-2016 19:37

OK Thanks...

By 803056

Date 10-22-2016 20:27

Brent, my good friend, I have to disagree with one of your contentions.

As long as the base metal is listed in Group I, selected from Table 3.1, a non-low hydrogen electrode can be used to weld the joint. If all the remaining conditions of prequalification are met, i.e., the use of a prequalified joint is selected, a matching filler metal is used, a prequalified welding process is used, the preheat per category A as shown in Table 3.3 is used, and all the other conditions listed in Clause 3 are met, the WPS is prequalified. The point being just because the WPS includes a base metal listed as a Group I and is welded with an non low hydrogen electrode, it does not necessarily mean it must be supported by a PQR.

Can any of the base metals listed in Table 3.1 be welded with a low hydrogen electrode and can the WPS be prequalified? Yes, if all the other conditions of Clause 3 are met.

Can the welder that is qualified with an F4 electrode weld with F4, F3, F2, and F1 electrodes? Yes, if the qualification tests qualifies the welder for the positions used in production, for the weld type, and the product form, i.e., fillet or groove and structural shape versus pipe and tube.

Best regards - Al

By welderbrent (*****)

Date 10-22-2016 23:55

You are totally right and thank you for catching me on that. I was in the middle of working through some MTR's on a job and got out of line there. My mind was going to not being able to use it for structural work and I threw it in with needing a PQR. Now who is mixing their fruits? OOPPSS.

So, now I have to take a look back and see how that goes with what was asked when I threw all that out.

He Is In Control, Have a Great Day, Brent

By 803056

Date 10-23-2016 01:28

Hey buddy, we all make a mistake now and again when we read something quickly or shot from the hip and end up shooting ourselves in the foot. I have a permanent lip these days. Besides, it makes for a more interesting discussion.

Best regards - Al