Prequalified WPS

By swnorris (****)

Date 10-24-2007 18:09

In the Base Metals category, a typical WPS form might show:

Material Spec. ___________ to ___________

Type or Grade ___________ to ___________

Does anyone have a problem with the fabricator filling in the above blanks with: D1.1 Group I & II to D1.1 Group I & II

I've seen some prequalified WPS's that state specific prequalified grades to specific prequalified grades, but when this is indicated, it limits the user to those two or three grades only, and then other WPS's have to be written to cover other instances when using prequalified base metals. Seems to me that a generic statement of D1.1 Group I & II to D1.1 Group I & II would give the fabricator more options within the single WPS using prequalified base metals, as the base metals in Groups I & II cover 99% of the base metals used in structural applications.

By drifter57 (**)

Date 10-24-2007 18:54

I sure hope it is ok, thats the way mine read and nobody has had issues with it.

By eekpod

Date 10-24-2007 19:18

Ours are the same way as well,... but I have bben advised it also would be a good idea to have a couple written with a narrower set of base metals. Such as A572-50 to A572-50, A527-50 to A36, just the most "popular" ones you might use, then you can always fall back on your more generic group I,group II if you have to. Good Luck, Chris

By 803056

Date 10-24-2007 22:32

I see no problem with it as long as your welders know the difference between Group I and Group II materials and/or have access to a copy of D1.1 or D1.5 or ASME Section XXXXX.

However, most welders don't have access to the appropriate code or for that matter, most couldn't tell you the color of the cover or if it even has a cover. That being the case, what useful information does Group I or Group II provide?

Who is the WPS written for? If you believe the WPS is written to provide useful information to the welder, you have to put in information he/her can read and use.

I use an annex that list the appropriate base metal specifications and I reference the annex in the WPS. Every welder has a copy of the appropriate annex for reference. So, my WPS for Group I carbon steels lists Annex A-S1. In the annex, Annex A-S1, would be listed each of the base metal specifications and grades, i.e, A36, A500 Grade B, A106, etc. The annex only has to list those materials you expect to use. In the event you have another project that calls for a base metal that can be added to Annex A-S1, A53 for instance, add it in to a growing list of materials that fit the bill.

Hope that tweeks your interest.

Best regards - Al

By drifter57 (**)

Date 10-25-2007 10:11

Exellent point

By swnorris (****)

Date 10-25-2007 13:22 Edited 10-25-2007 13:42

803056,

It's for internal use. I just wanted to get a sampling from other D1.1 users. When I include Group I and Group 2 materials, that covers 99.9% of the material grades used in structural steel fabrication. If I narrow it down to specific Group I and II material grades, or a combination of the two, I would have to write a WPS for pretty much every material grade and/or every material grade combination that we use. For example, if the WPS states A36 3/4" thick or less, to A500 B (both Group I), no other materials can be used with that procedure. If I write a WPS for A36 3/4" thick or less (Group I), to A36 greater than 3/4" thick (Group II), no other materials can be used for that procedure, etc., etc., etc.
We use A36, A53 B, A500 B, A572 Grade 50, and A992, and, useful information is included in the WPS, and, the welding parameters for these grades are pretty much the same. It's very user friendly, because if the welders can't easily understand it, it's worthless. All our welders know and understand it's contents, and I occasionally have meetings to refresh the welders. I also question welders as I walk through the shop from time to time. I also hold classes on the prequalified PJP and CJP's so that the welders fully understand the meanings of the joint designations, the symbols, the different joints, joint limitations, etc. Welders don't need to be overwhelmed with the contents of the entire code. I include what they need to know on the WPS, and in various classes, and after they absorb that and want to learn new things in the code, I dont hold them back.

By rickc

Date 10-25-2007 14:54

Been doing it that way for years and our procedures get reviewed by third parties almost every time we weld. It most certainly complies with the code.

By 803056

Date 10-26-2007 00:02

Sounds like you have a system that works.

I only object when the WPS is written in such a way that the welder can't decipher the information it contains. I have yet to encounter a group of welders that understand what a S1, P1, or Group I base metal is when the question is asked before a training class. That being the case, simply listing P1 to P1 is of no use to the welder that hasn't been given the proper training. I don't blame the welders, I blame their management.

Best regards - Al