METHOD FOR PLASMA OXY-CUTTING FERROUS METALS

摘要

Disclosed is a method for operating an installation used for plasma oxy-cutting metallic workpieces that contain at least one ferrous material. Said installation comprises a central nozzle (1) delivering an oxygen-containing gas stream for cutting, an intermediate nozzle (2) used as an electrode (9), which is coaxially aligned with the central nozzle (1) and delivers a first annular plasma jet, and a peripheral nozzle (3) which delivers a second annular plasma jet and is coaxially aligned with the intermediate nozzle (2). The workpiece is preheated in an initiation area, pierced across the entire thickness of the workpiece to be cut, and then cut according to a desired cutting kerf. The nozzle (1) is electrically insulated from the electrode (2) and from any other part of the installation having the same potential as the electrode while the inventive method is carried out.