14 Ga. SS butt weld

by mike h
(Green Bay Wi. Wi)

Hi,
I work for a paper converting machine Manufacturer and work as a welder/fabricator. One component we fabricate is made of 14 Ga. SS, and can vary in size but basically is two 1/4 radius's that might be between 3.87 to 5.87 and have a straight section between. One is beveled to a 10 or 15 degree angle.The non-beveled section is welded to the beveled section, they have aluminum plates bent to the correct angle and varying in width for most applications. The problem is welding the straight section between the two radius's. This section always pulls and warps down away from the weld. Because of the variety of the component configuration a component specific jig/slug would be impractical. I think that the weld deflection is caused by sugaring on the back side of the weld. I think that supplying gas(argon) to the back side of the weld (purge) would weld both sides at the same time. I was wondering if you think that this purge approach would work. I have attempted to get the gas behind the weld with a crude jig and were able to reduce sugaring but couldn't get enough gas to weld both sides. Do you think this approach merits more effort or any ideas on a different approach.
Thanks,
M.H in G.B


--------------------------------------------------

yes i do think the idea merits more effort.

sometimes the sugaring causes more heat input just to get the puddle to flow.

when stainless is shielded, it takes minimal heat for a nice tight weld and that usually means less warping.

also some thick aluminum chill blocks clamped to both sides of the weld and beveled to allow for welding might help