GB1322828A - Plasma arc furnace - Google Patents

Abstract

1322828 Plasma-arc furnaces INSTITUT ELEKTROSVARKI IMENI E O PATONA AKADEMII NAUK UKRAINSKOI SSR 29 Sept 1971 [1 Oct 1970] 45418/71 Heading F4B [Also in Division B3] In a plasma-arc furnace, particularly for melting sheet scrap of highly reactive metal such as titanium, an ingot mould 3 and a hopper 5 for the scrap are mounted in the lower and upper parts of a furnace chamber, and a water cooled base-plate 13 formed with at least one guide trough 14 is mounted between the hopper 5 and the ingot mould, apparatus mounted below the hopper 5 pushing material along the trough 14 to a melting zone. The hopper 5 is divided into cc mpartments each containing sheet scrap 7 cut to size and having a gate controlled outlet at the bottom near the base-plate 13. The hopper 5 is mounted above the feeding apparatus, with pusher heads 23 aligned with slots in the bottom of each compartment and with the troughs 14. A screw 18 driven by gearing 31 moves a carriage 16 along tracks 21, Fig. 4. The pusher heads 23 are pivoted to the carriage 16, so that when the carriage is rapidly retracted they can rotate against springs 25 to slide below the scrap in the container. Scrap pushed along the troughs 14 is melted as it comes within the zone heated by the plasma torch 2, and melted metal falls into the mould 3. Two or more hoppers and charging devices may be arranged round a single mould. The mould 3 is mounted in a casing, and has a dummy bar and grippers for coupling to an ingot discharge device. The furnace has provision for gas circulation and recovery, and a safety pressure control is mounted on one hopper.