Method and apparatus for DC reverse polarity plasma-arc working of electrically conductive materials

摘要

A method of DC reverse polarity plasma-arc machining of electrically conductive materials with the aid of a plasmatron the plasmatron having a nonconsumable electrode with an insert made from a high-melting point material, the method being in that the material being machined is heated by the heat of an electric arc burning between the positive nonconsumable electrode of the plasmatron and the material being machined, with the supply of the plasma-forming gas, the intensity of the working current of the arc being selected such that its ratio to the diameter of the nozzle channel is within 50 to 100 A/mm on condition that at least a portion of the near-the-electrode zone of the arc is maintained in electric contact with the high-melting point insert of the electrode.