Welding Stainless Steel Sheet Metal

[FreezingGator]

I have an application that requires welding several sheets of 12ga 304L SS together. I'm concerned about warpage and deformation during the welding process. Does anyone have recommendations about welding process or reinforcement of the material (hat channel, ribbing, etc.) that would help make this a success?

 

[metengr]

Can you come back with more information as to the joint or joining detail of the 12 gage sheet metal and application?

 

[FreezingGator]

The application is a freezing chamber that will experience daily temperature ranges from -45F to +180F. This part of the chamber is the floor so there will be 12 to 16 of 4'x8' sheets welded together to form a single piece. The joining details could either be a seam to seam joint, an overlap joint (the edge of one piece on top of another) or a rolled edge joint (two pieces with bent edges come together at the seam). We prefer to have the overlap joint stlye without all of the rolled edges so we're looking for someway to reinforce the sheets in order to not warp during the welding process.

 

[metengr]

The lap joint welding detail should work. Your biggest problem will be to design external stiffeners on the chamber floor to avoid thermal distortion in service versus distortion from welding. I would suggest you review ASME Section VIII, Div 1 for external stiffener design guidelines.

 

[stanweld]

In terms of welding process, GMAW short-arc or pulsed transfer is recommended to best control heat input (low) and distortion when filler metal additions are required. Plasma arc systems and pulsed GTAW systems, without filler metal addition, are also used; best distortion control using an automatic process thereof.

 

[palecactus]

you could stitch weld the seams. tack all together and then weld 5" or so and move 2' and weld another 5" keep moving around so your heat doesnt build up in one area.