VERFAHREN ZUM HOCHWERTIGEN PLASMABOGEN- UND LASERSCHNEIDEN VON ROSTFREIEM STAHL UND ALUMINIUM

• Main Authors: COUCH, RICHARD, W., HANOVER, NH 03755, US, LU, ZHIPENG, LEBANON, NH 03766, US, STENFELT, STAFFAN, C., O., S-360 30 LAMMHULT, SE, LUO, LIFENG, LEBANON, NH 03766, US, SANDERS, NICHOLAS, A., NORWICH, VT 05055, US
• Format: Patent
• Language: German
• Published: 09.07.1998
• Edition: 6
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

Plasma arc or laser cutting uses a mix of reactive and reducing gas flows to cut sheets of stainless steel, aluminum and other non-ferrous metals. The reducing gas flow to the cut varies as a percentage of the total gas flow to maintain a reducing atmosphere down through the cut, but to leave a predominantly oxidizing atmosphere at the intersection of the cut and the bottom surface of the sheet being cut. In plasma arc cutting these flows can also be characterized as either a plasma gas flow, one that forms the arc, or a shield gas flow that surrounds the arc. The reactive gas is preferably a flow of air, oxygen, nitrogen, carbon dioxide or a combination of these gases. The reducing gas is preferably hydrogen, hydrogen 35, methane, or a mixture of these gases. For aluminum, the reactive gas is preferably air or nitrogen and the reducing gas is preferably methane or a mixture of methane and air. In laser cutting the reducing gases such as methane can be used by mixing them with reactive assist gases.