One of the frequent uses of seam welders is for metal barrels or cylinders. Barrels are used in all sizes and are seam welded on longitudinal welders. Here the part runs into the throat of the machine and then is reversed and run back out. The seams are fluid tight and are used in many industries. Most barrels are roll formed to install a gusset for strength after welding. This gusset will be the lip which holds the top and bottom end pieces. The seam weld will maintain its integrity even after these forming operations.
Cylinder or barrel welder
Note the two seam welding wheels. The upper wheel is driven and moves the part in and out of the machine.