GB573433A - Improvements in or relating to the manufacture of castings - Google Patents

Abstract

573,433. Casting processes. ENFIELD ROLLING MILLS, Ltd., and METZGER, O. J. Aug. 5, 1942, No. 10954. [Class 83 (i)] Moulds.-Castings are made by immersing a fluid-cooled mould or core in molten material so that it freezes to a desired surface thereof, freezing onto the rest of the immersed surfaces being prevented by a heat-insulating layer. The mould may comprise a water-cooled copper box 11 shaped at 12, 13 to conform to the casting desired and insulated by an asbestos sleeve 23 from a clamping sleeve 19 on which is screwed a collar 16 adapted to hold an uncooled and perforated mould member 14 which limits the solidification and produces the desired shape of the side and lower face of the light alloy casting. Air escapes from the mould by vents 26. For casting a hollow cylinder, the box 11A, Fig. 2, has insulation on its bottom 27 instead of its sides and an open-ended limiting member 14A with vents 26A. The box 11A is slightly tapered and the casting is stripped at once. In another modification, a divided limiting member is used to facilitate ejection of the casting or the limiting member may be omitted, the thickness of the casting depending on the time the cooled mould is immersed.