They are weldable, just grind some of the plating off, that's probably whats making it not stick. I opened this thread cause I thought you were going to be asking if you could weld one back together or something. For your own safety, please don't. If you can get a nut welded on to get the old one out, replace it. And if you burn the belt at all, replace it. If you can't get a nut welded on, you might be able to use a cold chisel and a bfh, and catch an edge and beat it in the normal rotation to loosen it, then grab it with some vise grips. Good luck