Method of arc control in plasma arc furnace torches
US3980802A · kind A · utility
Inventors
Key dates
| Filing date | Aug 20, 1974 |
| Grant date | Sep 14, 1976 |
| Priority date | — |
| Expiry date | Aug 20, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H1/3478
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A plasma arc remelting furnace system with improved components including mechanisms for independently vertically feeding and oscillating the metal blank through the top of the furnace. Multiple plasma arc torches (plasmatrons) are installed in a sealed chamber and adjustable operators enable angular disposition of individual torches. The torches have improved torch nozzles with heat sink construction enabling operation at higher temperatures, better stablized plasma arcs and longer torch life. The system can utilize ingot molds of various cross section shapes, i.e., round, square, rectangular and polygonal and, depending upon mold shape, the number of torches can differ. Operating circuits are provided for use with a plurality of different numbers (up to eight) of torches, either with direct current or alternating current power sources, and possible variations of circuits will enable using a larger number of torches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.