I am working with AWS D1.1:2015. During the assembly of our current project, we found a handful of joints in 1/4" material that had a root opening of 1/8” to 3/16”. These joints require a 1/4" fillet weld. According to 5.21.1, we are required to increase the size of the fillet weld legs to accommodate that gap. This poses a problem because we are using A572, a group II metal, and our single pass fillet weld size is limited to 5/16”. This would make it impossible to perform the 3/8” welds needed to fill the larger gaps. I would like to use a backing weld to fill the gap before welding, but I have a couple of questions.
Does a backing weld require a WPS? If so, would that weld be classified as a PJP groove?
If a backing weld is performed, does that negate the requirement to increase the weld size?
Thank you guys in advance for your time.
Multiple pass fillets to deposit the required weld size that accommodates the actual root opening in excess of 1/16 inch.
Al
That's what we'll do. Thank you Al!
Please note, a 1/4" fillet weld with a 3/16" root opening will yield a 7/16" multipass fillet weld, not a 3/8" fillet weld.
Clause 5.21.1 and its' commentary states that the additional size is based upon the amount of opening.
A gap up to 1/16" the weld may be as specified on the drawings. Over 1/16" the size increases by the amount of opening not by the amount of opening minus 1/16.
Just making sure that was clear based upon your OP measurements.
He Is In Control, Have a Great Day, Brent
Upon rereading my post I see where you could see that the increase in leg dimension is only for the root opening in excess of 1/16 inch. My bad, poor choice of wording.
It was a good clarification Brent.
Al
It wasn't as much about how you said it as how the OP had said it but between the two I didn't think it was clear enough.
Have a Great Day, Brent
By 803056 
Date 04-24-2018 13:44
Edited 04-24-2018 17:05
I'm glad you did clarify the point. Good catch.
Al
That makes a lot more sense. I didn't realize that. Thank you Brent!
