GB1350723A - Method of compacting powdered metals and furnace therefor - Google Patents

Abstract

1350723 Vertical electric furnaces CRUCIBLE Inc 10 April 1972 [21 July 1971] 16494/72 Heading F4B [Also in Division E2] A vertical electric furnace used in the sintering and compacting of powdered metal comprises a refractory lined cylindrical chamber 16 closed by a two-sectioned lid 36, resistance heating elements 72 and a pedestal 86 movable vertically between the top and bottom of the furnace to receive a cylindrical steel container 78 for the powdered metal charge. The container 78 is surrounded by a heat insulating casing 82 and has a connection 80 through which it can be evacuated. The pedestal 86 comprises a heat resisting alloy casing 86 containing a castable refactory 90 and has a plate 92 connected to a shaft 94. The latter is connected at 114 to one end of chains 110 passing over pulleys 106 on a shaft 104, the other ends of the chains carrying counterweights (112, Fig. 4). A motor 98 drives shaft 104 through chain and sprocket gearing to raise and lower the container 78. The resistance elements 72 comprise horizontal rods which may be connected in sections to individual lead wires 76 through connector boxes 74. Sight holes 73 may accommodate optical pyrometers. The two-sectioned lid 36 comprises upper and lower plates 38 and 40 enclosing insulation 42 and connected by the rods 44, said plates 38 being connected by trunnions 46 to shafts 50. The latter are connected by pivot links 54 to parallel shafts 60 each driven by a pneumatic motor 62 and each associated with a counterweight 77 connected to said shaft 60 by chain and sprocket gearing 61-69 and linkage 71-75.