GB540247A - Improvements relating to the production of metal strips or sheets - Google Patents

Abstract

540,247. Casting-machines ; rolling. HAZELETT, C. W. April 5, 1940, No. 6212. [Classes 83 (i) and 83 (iv)] Molten steel, nickel, nickel alloy, lead, or other metal is poured on to the surface of a continuously moving cooling member which allows it to spread freely and carries it to means, at a distance from the pouring point, for rolling it into a strip or sheet. A broad stream of metal is poured from a pivoted box 28 on to a baffle 33 and thence on to a water-cooled ring 5 supported and driven at 120 to 2000 feet per minute by a roller 1 and preferably kept at 250- 800‹ F. The stream engages the ring at a point not more than an angular distance of 40 degrees from its highest point and is urged to follow the ring's movement by a blast of reducing gas, flames, &c. at 34. A water-cooled roller 35 cools its upper surface and it is rolled less than 1 minute after it has been poured, by a ring 9 and water-cooled roll 8 to reduce its thickness without restraining it from spreading laterally. The roller 1 is pressed upwardly, to give a rolling pressure, preferably between 125 and 1000 lbs. per inch width of the strip, by a hydraulic cylinder 10 and lever 11, acting on. each bearing 14 of the roll 1, the thickness of the rolled product being indicated by pointers adjustably connected to each bearing and regulated by a rheostat 43 which is connected to the lever 11 and arranged in the circuit of a shunt winding 44 of the motor 45, which drives the roll 8 and thus vary its speed. The finished strip is removed by a scraper 42 and may be re-rolled to a thickness of 0.01 inch with or without reheating or may be cooled and rolled up or cut into lengths. In a modification, instead of providing an air &c. blast 34, the pouring box engages the ring 5. For high melting-point metals the box has a refractory lining and is shod, where it engages the ring 5, with copper or nickel, This ring-engaging lip may have a number of feed channels. A brush may be arranged to remove scale from the cooling member or these may be made heat resisting alloys containing chromium, nickel, or molybdenum. For small quantities of metal or for metal of low melting point, the cooling member may be a roll 23, 38 and 40 are water cooling means. If the pressure in the first roll pass is very low, e.g. under 125 pounds per inch of width of the whole strip this has the characteristic of cast metal but at greater pressures the portion in contact with the lower roll or ring 5 has these characteristics but the upper layer has those of worked metal, e.g. in the case of aluminium the lower surface is resistant to corrosion and the upper is ductile. Casting composite strips. - In another modification one or more preformed and preheated metal strips 74, Fig. 6, are interposed between the molten metal and the cooling ring &c. 71 or applied to it after pouring or both. The preheating furnaces 75 may have reducing atmospheres and the compound strip may be re-rolled at 73.