GB735155A - Apparatus for delivering metered shots of molten metal for castings - Google Patents

Abstract

735,155. Casting-machines. DOW CHEMICAL CO. June 26, 1953, No. 17844/53. Class 83 (1). Apparatus for delivering metered shots of molten metal, e.g. magnesium or its alloys, to a casting-machine, e.g. to the shot cylinder 93, Fig. 1, of a pressure-casting machine, comprises a pipe 34 having one end 15 positioned in the melting-pot 4 and provided with a valve 18 movable to open position by pressure-fluid applied above a piston 29, and to closed position by a spring 31, the period of opening determining the amount of metal passing to the pipe 34. The other end 36 of the pipe lies above the end 15 and has thereon a delivery end 42, Fig. 3, having a bore 44 terminating in an outlet orifice 49, in a face 47 sloping at not more than 10 degrees to the horizontal. Pipe 34 may be lagged and heated by an electrical resistanceheater 92. Gas, e.g. SO 2 ; BCl 3 ; BF 3 ; or dichlorodifluoromethane, is ejected from pipe 50 via nozzles 51 to surround the orifice after delivery of each shot to cause the molten metal at the orifice to form a skin strong enough to support the head of metal above it, the only volume of metal lost should the skin break being that extending back to level 63. The orifice is positioned above an opening 94 in the shot cylinder 93. In another arrangement, the delivery end 64, Fig. 6, comprises an elbow and ends in a member 68, Fig. 7, containing an inverted cup-shaped part 75. The outlet orifice member 82 is screwed into the base 70 of member 68 and extends into part 75, holes 78 providing communication between the interior of member 68 and the bore 81 of the orifice member. An annular pipe 86 receives the skinforming gas and has nozzles 87 directed towards the orifice 88.