20100084381 | PROCESS FOR THE PLASMA SPOT WELDING OF SURFACE-TREATED WORKPIECES AND PLASMA TORCH - A process for plasma spot welding of surface-treated workpieces using a plasma torch comprises supplying a plasma-generating gas to the plasma torch, connecting a first terminal (−) of a current source to an electrode of the plasma torch, connecting a second terminal (+) of the current source to a workpiece, building up at least one plasma arc from the electrode of the torch toward the workpiece by applying electric current (I(t)) from the current source to an anode-cathode path between the electrode and the workpiece. The electric current (I(t)) is kept in a preprocessing current range (I | 04-08-2010 |