Question on a pre-qualified FCAW WPS.
Section 3.6 Limitation of WPS Variables.
Pretend I have a written WPS that lists my base metal as, let's say A572-50. Can I use that same written WPS to weld A36 as written?
Here's why I ask. We had our AISC audit today, and the auditor was pointing out how they are now trained by AWS to read and look for more welding related issues. He explained that Section 3.6 Items 1-4 (Amps, Volts,Travel Speed,Sheilding gas flow rate) need to be on a WPS, and that if any changes are made that a new written WPS must be made. Items 1-4 don't address base metal.
So simply by his view point, any base metal can be filled in and it doesn't need to be changed.
By the way I don't agree w/ that statement, I'm just pointing out where he was coming from.
Our base metals list Group 1 or group II, this way it covers the entire grouping of material, he didn't like that because it was too broad. I said it met the code. I agree w/ him that it is broad but it's ok as is. That got me thinking, by his way I would need to write a WPS for all the different combinations of different material. BUT because 3.6 items 1-4 don't mention base metal does it HAVE to be re-written?
In 3.6 I take into consideration the previous sentence "within the limitation of variables described in Table 4.5 for each applicable process". Table 4.5 item 29 says "A change in base metal ". I took that to mean if you change base metals, you must change the WPS to follow. Again that's why they wrote it w/ Group I/II to account for all those materials, this way you don't have to write a new one every time you weld a different type.
Open to thoughts and perceptions, thanks
I am very curious to see how your auditor address this. We are getting ready for our AISC audit and have our WPS base metals as follows:
Base Metals:
Mat'l Spec.: AWS D1.1-04 Table 3.1 Group I or II
Type or Grade : A36, A992-50, A53, A500B, A572-50
We had help in writing our WPS with an AWS inspector from a local testing agency.
The code does not address this issue specifically, so as far as I'm concerned anyone who says that the code requires you to do this or the code requires you to do that with regards to this question is just blowing air.
Now there are good quality control practices. These practices state that you write what you do and do what is written. So the answer to your first question is "no", if you procedure says use A572-50 then you cannot substitute A36. Now, if you write Group I or Group II then yes you can, but you've just widen a parameter quite a bit. I'd be interested in seeing how this affects your other variables such a filler metal and preheat. The only safe way I see for these two is to reference back to Tables 3.1 and 3.2, but doesn't that make the procedure less useful if you have to track down the big red book to figure out what filler metal and preheat is necessary to stay within prequalified limits.
I like the idea of keeping each procedure tight but having a procedure ready for anything that comes at you. If you have a good document creation and tracking system established then this should not be a big problem.
Well, we passed the audit w/out any CAR's, so that's good. He just left it as it's not the easiest way to get the info across but it will work. I agreed w/ him that's it's not the best but it was written by someone else a few years ago, if I get extra time I would like to streamline them to make it simplier to use, but for now wer'e good.
Maybe instead of just group I/II something that covers a majority of them , and a basic group I/II in any other case, just to keep on file. Thanks Chris
Any other items that your auditor was critical of? Any suggestions to make sure we are prepared to pass the audit?
If you qualify a procedure with A572-gr50 then that does qualify you for A-36. A-36 is also a group 2 steel. You must weld it with the same parameters that you qualified the A572 with + or minus - the essential variables 15% and 10% of voltage and WFS. If you go to table 4.8 page 143 it will also tell you that qualifying 2 pieces of A572 GR50 together will qualify you for any group 1 steel to any group 1 steel / any group 2 steel to any group 1 steel/ or any group 2 steel to any group 2 steel. So show the guy next time your pqr for your A572 gr50 to A572 gr50 and open the code book to page 143 table 4.8 and say well i guess were good for right now, but i'll work on it. (yeah right) blow some smoke in his ear to make him happy and feel all warm and fuzzy inside.
Topic American Welding Society Services / Technical Standards & Publications / D1.1 Pre-Qual WPS Question, Section 3.6
