METHOD OF PLASM-ARC CUTTING OF METAL AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2008 - IPC B23K10/00 

FIELD: technological processes.

SUBSTANCE: device contains two-nozzle plasmatron (1), which contains of copper electrode (2) with high temperature insert (3) and two nozzles inserted one into the other - internal one (4) with diameter d_i and external one (5) with diameter of d_e. Ratio d_i/d_e stays within limits of 1/1÷1/1.2, and distance h between internal (4) and external (5) nozzles is within limits of 0.3d_i÷0.7d_e. Electrode (2) is connected to positive pole of source (9) of electric power supply, to negative pole of which cut metal (10) is connected. During cutting plasmatron (1) is installed close to metal at the distance H, which is selected from the ratio of 2.5d_e≤H≤7d_e, between external nozzle (5) and metal surface (10). Then oxidizing gas is supplied to external nozzle (5), with flow rate Q_ox, and to internal nozzle (7) - inertial gas tangentially in respect to electrode (2) with flow rate Q_in, with ratio of mentioned flow rates of 1/20≤Q_in/Q_ox≤1.5/20. Then electric power supply source (9) is connected, as a result of which arc (11) is produced between electrode (2) and metal (10), which cuts the metal.

EFFECT: reduction of net cost of cut long meter and increase of metal cutting reliability.

3 cl, 1 dwg, 1 ex, 1 tbl