Hey all-
I have a job here that calls out E7028 filler rod to be used on A36 plate in accordance with D1.1. My question is, can I use a different process besides SMAW, perhaps FCAW or GTAW, to achieve the same results that E7028 would give me? My welders a certified using GTAW, since that is what the majority of our work requires. I would rather utilize the processes that our welders are most familiar with, if I can.
Thanks
Jason
Jason,
7028 is a low hydrogen rod, you are probably using wires that are basically a low hydrogen class compatible as well. The job specs usually say that you can shop weld at fabricators discretion vs field weld. The field welding is generally the purpose for calling out the SMAW rod to be used.
Personally, I would run it by either the inspector or the customer (or their engineer) just to verify that they don't have a problem with the change. But code wise it should be no problem. See Table 3.1 in D1.1.
If WPS are already in use, do you have proper on hand to make such a change? Check all your essential variables.
Not sure what else to cover with the information given.
Have a Great Day, Brent
Thanks Brent-
Right now, it looks like I'm going to have to write up a WPS for this job anyway. The job has 5" thick plate, which we are not qualified for at this time. But let me ask, just so I'm straight on this. According to 3.3, and Table 3.1 (Group II Steels), I can use ER70S-x (GMAW) or E7XT-W (FCAW) in place of E7018 or E7028? Right"
Thanks again
Jason
If the project specifications indicate the requirement for 7028 then a request for deviation could be submitted.
Your Company name would like to deviate from the requirement containined in Para xxx.xxxx which requires the use of AWS Classification E7028. We would like to use the GMAW/FCAW process using E(r)70S-x or E7XT-X. .
Even thoogh the code allows something, that does not mean your customer will. As far as the code goes, whats OK with 7028 is OK with GMAW/FCAW of similar strength.
Jason, also look at footnote 'e' for Figure 3.3; p.73 of 2006; and compare with 5.3.4. In my, emphasize 'my', opinion/interpretation 'Yes'.
If anyone has a different take on this I would appreciate their opinion as I'm sure you would as well. I have been told many times by the CWI's checking my shops' work that in the shop its' my call within certain perameters. When dealing with A-36 things are pretty flexible and any of the processes listed should be interchangable.
Like I said though in my first post, I would check with the engineer or customer for an official ok. Even the inspector if you have contact with one who would be working on the project.
Have a Great Day, Brent
A 7028 electrode is designed for 1G, 1F and 2F welding and will deposit weld rather quickly. Although your men may prefer GTAW, one would think it would certainly be a much slower weld if time is a concern. (and really, when isn't it time=$$$$$$$ )
Jason,
AWS D1.1:2008 Paragraph 3.2.2:
You could use GTAW, since it is a code approved process but, the WPS' need to be qualified in conformance with the requirements of clause (section) 4.
Note sure what code your current WPS'/PQR's, and welder qualifications are done.......
As it is dicussed in another post; time is $$$$. So how much $$$$ needs to be spent to save a little time?
It certainly will cost some money to requalify your welders, if all they have is GTAW qualifications.
Take a look at the overall weldment istself. Thickness, joint design, total amount of weld metal that will have to deposited. The list can go on and on.... Will other processes be better? You have already started to ask that question.
GTAW may be slow but, slow does not always mean it will cost more money in the long run.
If you choose to stay with GTAW, then really look at clause(section 4) in the D1.1. It will help you with the WPS/PQR, and welder qualifications.
Look at Table 4.5 for your WPS/PQR concerns, and Table 4.12 for your welder qualifications.
Thanks for the pointers guiys. It's much appreciated! At this point I'm ruling out GTAW, for reasons already stated, and am leaning toward FCAW. Simply because my welding personel have used it plenty, but not for code work, and neither has used SMAW in over 8 years that I know of. Plus I feel that that the FCAW qualifications could carry over to other jobs (in our shop) more so than than SMAW.
Jason
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