GB459304A - Improvements in metal casting systems - Google Patents

Abstract

459,304. Casting-machines; furnaces; crucibles. WETHERILL, S. P., Haverford, and SHOEMAKER, F. F., Chestnut Hill, both in Philadelphia, U.S.A. July 8, 1935, No. 19459. [Class 83 (i)] [See also Groups II and XII] A machine for the pressure-casting of steel &c. has a pressure chamber 1, Fig. 3, of refractory graphitic material supported by a metal casing 8, 9, through intermediate refractory material 18 and struts 6 of silicon carbide. The hearth 7 of alumina or like refractory is covered with high temperature cement and rests on a sheet a of asbestos on a plate 21 of metal carried by adjustable screws 22 to equalize the pressure. The hot gases from a burner 26 pass below the chamber 1, which may be arched for strength where unsupported by struts, then through flues 38, 39, 41 in the layer 18, of which 39, 41 are adjacent the outlet 4 which has a nozzle 32 of silicon carbide heated by a burner 37. The inlet 3 has a fitting 31 of non-metallic refractory with an asbestos washer 46 and a compressedair supply-fitting 43 with a baffle 45, which can be clamped down on the chamber 1, after charging, by means of a lever 47. The casing 8, 9 is carried by trunnions 11, Fig. 1, on a frame 14, so that the chamber 1 may be easily emptied, and is supported in use by a removable bar 17 and a spring 15 which will yield if the pressure of the applied mould 52 is excessive. A recess 42 is provided to prevent air from passing from the inlet 3 through the somewhat porous material into the outlet 4. The cover 33 is of non-conductive refractory material. In a modification, the sides of the chamber 1 are spaced from the layer 18 to form a flue and are supported by struts 56, Fig. 8, of silicon carbide pressed forward by adjustable springs 58. Some of the struts 6 may be located in the vertical plane of the inlet-3 and outlet 4.