Method of and welding torch for arc welding

摘要

Plasma-MIG welding in which a thermally ionizable gas stream is flowed through a nozzle non-consumable electrode having a central orifice and a surrounding annular opening toward a workpiece and is thereby split into a central gas column enveloped by an annular gas shield. A consumable electrode is fed through the central gas column toward the workpiece, with the establishment of a MIG-arc therebetween. A plasma arc is then spontaneously established by means of the MIG-arc between the nozzle non-consumable electrode and the workpiece. The central plasma gas column is accelerated by constriction of the annular gas shield downstream of the nozzle non-consumable electrode.