GB837473A - Improvements in or relating to apparatus for casting metals - Google Patents

Abstract

837,473. Continuous casting - machines; straightening. HAZELETT STRIP-CASTING CORPORATION. Dec. 18, 1956 [Dec. 27, 1955], No. 38584/56. Classes 83 (1) and 83 (4). Apparatus for casting metal strips comprises upper and lower endless flexible metal bands 14, 16, which move along spaced parallel rectilinear paths to define a casting-region, and are inclined to the horizontal. Molten metal passes from a ladle 2, at a rate controlled by a lever 10 operating a stopper, beneath a hinged flap 28 which serves to trap dross, and on to a grooved distributer 18. The flap and distributer ensure a non-turbulent evenly-distributed flow. The metal then passes into. the space between the bands 14, 16, which are of steel strip protected by a continuously-renewed lamp-black coating, or by " Bonderizing " (Registered Trade Mark), anodizing, oiling or sand-blasting, or by coating with an oxide, hydride or silicone. Two spaced dams 37, 38, consisting of metal or refractory blocks on a tape or chain, travel with the lower band 16 on its upper surface, to confine the metal. The dams are guided by blocks 48, 50, which also serve to contain the higherlevel of metal present at the end of the distributer 18. The blocks 48, 50 are liquid-cooled internally and are adjustable for different widths of strip by rods 68, 64. The bands are supported over the casting region by ribbed rollers 78, 82, between which are mounted perforated conduits 88, 96, which convey cooling water to the outer surfaces of the bands. Excess water on the upper band is gathered into scoops 102 and directed into gutters, and further scoops remove excess water from the lower band, thus assisting in maintaining a highvelocity cooling flow. The water drains into a large tank 110 from which it is drawn by a centrifugal pump and re-circulated, the water at the highest pressure being delivered to the hottest zone of the casting region. The band 14 is tensioned by a rubber-covered roller 142, which is pressed against the band by a pair of independently-acting air-cylinders 160. The pressure in the cylinders is controlled by a valve actuated by a follower engaging the edge of the band. If the band is not running true, the follower is moved to cause the roller 142 to tilt and return the band into its correct path. A similar tensioning means 206 is provided for the lower band. To permit access to the parts of the machine and easy removal of the bands, the lower band assembly is supported on the ends of cantilever beams 222, 224, and the upper band assembly on two beams, such as 240, sliding on rods 254, 256, and raised and lowered by a fluid-pressure-operated piston 264 acting through levers 242, 244, the spacing of the assemblies in operation being determined by gauge-bars 268, 270. During casting, a counterbalance pressure is applied to the upper assembly by the piston 264 so that, in the event of incorrect functioning, the upper assembly may lift and prevent damage. The bands are driven by a motor 272 through chain gearing 274. Straightening.-In order to smooth and level the band 14 it may be pressed downwardly by a roller 214, controlled by a handle 216a, against rollers 210, 212, thus causing the band to be bent in two directions to stretch and level it. Specifications 837,474 and 837,475 are referred to.