7018 Fillet Weld Break Test

By jcrooke Date 02-10-2009 20:46

I would like to get some clarity on the requirements for passing a fillet weld break test. I am qualifing welders in 3F using Linc 7018ac 1/8 & A36 plate. From what i understand, in break test the ideally the weld will break down the middle of the weld. If I am reading D1.1 4.30.4.1 (1) correct as long as it bends flat on itself it passes. Does this mean that if the weld itself does not break but pulls away from base metal it passes. More specificaly when it pulls away it pulls base metal with it. Not what I would necesarly call lack of fusion.

By 803056

Date 02-11-2009 16:14

I always make sure the two plates separate so I can look at the root to verify the fusion extends to the joint root, but not necessarily beyond.

Best regard - Al

By Kix

Date 02-17-2009 13:45

You're lookinf for root penetration and fusion out on the legs. If you're using thin enough plate that it will bend over on itself after welding, then yes that passes. Like Al said, I too break mine clean in two pieces so I can inspect it thoroughly when using thicker plate. If you want to see if they are getting good pen and fusion on the thin stuff you might be better off doing a macro etch. If the thin stuff bends over on itself and you see the weld peel off the plate a little, check to mak sure that it pulled base material with it. If it did then you are still A OK. If the part that peeled shows lack of fusion and is in the test area of the coupon, I would fail it.

By Lawrence (*****)

Date 02-17-2009 14:38

Also also,

Since the test is for penetration and not for strength... It may be apropriate to quench the sample right after welding and slag removal... This often helps eliminate the bending of the sample.

By eekpod

Date 02-18-2009 23:00

I think you guys aren't intrepeting what the code says correctly.
D1.1 says something to the effect that fusion shall be to the root but not neccessarliy beyond, this is why you have to do a macro etch on the "drop" of the piece you cut off, to visually see if they penetrated to the root or beyond.
The bend test is an additional test to see how and where it breaks, also it lets you see if there is any slag trapped in there and if so how much, and if it doesn't exceed I think it's like 3/8" long in the 6 inch remaining coupon.
To answer the OP, yes, if it bends flat upon itself, and the macro etch shows fusion to the root, and assuming the visual inspection before all this destructive testing was done, I'd say yes they pass.
There's more to it than just bending it flat upon itself, that's if you do it per the code, and my understanding is that you can't go against it(or at least shouldnt')
Don't forget the stop and re-start in the middle of the coupon, thats a big part of it.
open for comments
Chris