Plasma welding is one of the newest welding procedures. It is a method of tungsten gas shielded arc welding. It involves a concentrated electric arc with a high energy density. The electric arc is created by a water cooled copper nozzle with narrow bore holes, through which the electric arc passes. It has an almost cylindrical shape, and diverges by just a few degrees. This results in a high energy density.
The electric arc burns on the needle-like tungsten cleaned using plasma gas. Indeed, the gas emitted through the small borehole can not provide long-range protection during welding. Shielding gas is therefore supplied through a second nozzle. The plasma welding procedure offers ignition reliability, and directionally stable electric arcs with low heat input.