Welds stopping short of edge

Date 03-09-2006 18:41

I simply see it as rejected due to the fact that the drawing says 4". If it is not a good idea to weld to the end of the joint because "burn out" is possible, this should be discussed with the enigineer. It is never the welders descision to do as he pleases because he sees a problem with the drawing. There may be more to it than discussed, but at face value, this is what I would do. As far as what AWS D1.1 says, I don't have a clue, I haven't dealt with it in a long time.

By swnorris (****)

Date 03-09-2006 21:19

The lengths of welds are to be no less than those specified by design requirements and detail drawings.

The welder has an undercut concern if he/she welds all the way to the edge, but it can easily be done without undercutting. Some welders can do it and some can't. It's all in their technique.

Will the shortened weld affect the performance of the weld?

It could. It depends on the types of stresses that the welds will be subjected to. I don't know how to calculate the weld strength for flare bevels, but just to give you an idea, if the weld were, say, a 1/4" fillet 4" long: .928 x 4 x 4 = 14.848 kips of weld metal strength. For that same 1/4" fillet 3 1/2" long: .928 x 4 x 3.5 = 12.992 kips of weld metal strength. That's almost 2,000 pounds less strength, and the calculations are based on the joints being properly welded, which could be another issue. I know thee's a safety factor figured into designs, but that would be for an engineer to decide. If your inspecting to D1.1, the welds are rejectable.

By CHGuilford (****)

Date 03-09-2006 22:38

In bridge welding, it is common to terminate welds some distance form the end of the joints. There is usually a detail indicating that, which may be on a general notes drawing or on each detail drawing. Those welds are deliberately planned that way.
If not indicated otherwise, the welds is supposed go to the end of the joint. D1.1 has the same criteria, if not called out on the drawing to hold back, the welds should go to the end.

In both D1.1 and D1.5, the welds are supposed to be interupted by a distance equal to the weld size when you have fillets on "opposite sides of a common plane of contact". That is so you don't get a small throated wrapping around the corner, or even undercut right on the corner.
This doesn't apply to your situation.

If the welds are otherwise acceptable and decent in appearance, I would check with the engineer to see if the welds can be left short. (In some cases the repairs might end up worse that the original problem.) The engineer may allow it or may not, but you will be viewed as doing your job and trying to work with the welders instead of searching for something to reject. (Not that you don't do that). In any case, I would not make the decision to leave the welds alone without checking it out.

Chet