METHOD OF AND DEVICE FOR PLASMA MIG WELDING

摘要

1449592 Plasma MIG are welding PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd 2 April 1975 [5 April 1974] 13429/75 Heading B3R In a method of plasma-MIG arc welding a consumable wire electrode is fed through a nozzle and a MIG arc is maintained in an arc plasma which is generated by maintaining a plasma arc in a gas flow between a non-consumable electrode and a workpiece and downstream of the non-consumable electrode additional current is supplied to the arc plasma by way of an annular auxiliary electrode. In the embodiments described the annular auxiliary electrode 5 (Fig. 1) and 57 (Fig. 2) is located respectively between the non-consumable electrodes 9 and 5 which constitute plasma arc nozzles in the respective embodiments and the electrical supply to the auxiliary electrode being independent of the power source 33 of the consumable electrode and from a power source 37 in Fig. 1 and by an independent tapping from the power source 31 in Fig. 2.