GB539983A - Improvements in and relating to the casting of metal ingots, and ingot molds for use therein - Google Patents

Abstract

539,983. Ingot moulds. TRIGGS, W. W. (Valley Mould & Iron Corporation). March 26, 1940, No. 5438. [Class 83 (i)] An ingot mould is provided with indentations in its inner surfaces to produce on the ingot quickly freezing projections of such form that they act, during the cooling and shrinking of the ingot 8, to centre it and keep a substantially uniform air space between it and the mould. The projections may take the form of ribs 9, Fig. 3, which also support the solid skin formed during cooling and avoid cracks therein. The ingot may have separate vertical and horizontal ribs or be covered with a trellis-like arrangement of ribs 9, 10 or 6, Fig. 11. The height of the ribs should not exceed 1/15 of the lateral dimension of the ingot at the point in question. In a modification the number of separate projections 30, Fig. 14, are formed. The inclination of the lower side of each rib or projection should be inclined, e.g. at 25 degrees to 35 degrees, to the walls to permit it to leave its groove 31 or indentation easily as the ingot shrinks and this inclination may be greater nearer the base. The central projection 18 in each row on each side of a rectangular ingot 8 has a rectangular section as shown in Fig. 15, while the other projections are inclined laterally as well as vertically to allow both movements relative to the mould 1 during cooling If a corrugated ingot 42, Fig. 20 is desired, projections 18 may be formed on the crests or, preferably, in the valleys of the ingot as shown. U.S.A. Specification 2,018,762 is referred to.