GB1427044A - Continuous casting method - Google Patents

Abstract

1427044 Continuous casting; composite casting; making rod B O N HANSSON and J O B HERTSIUS 9 March 1973 [10 March 1972] 11622/73 Headings B3A B3F and B3P A hollow body 7 of solid material, e.g. of Pb, Pb alloy, Al, is continuously extruded and molten metal, e.g. Cu, of no lower m.p. than that of the body material is passed into the body and the outer surface of the body is continuously cooled so that the metal is cast in the body, to form a billet 16 either from which the body 7 may be stripped (or melted) or to which the body remains joined as an integral part. As shown Pb is melted in a vessel 1 and passed to a screw feed of an extruder 3 where it solidifies around the screw 4 before being fed to dies 5, 6 for extrusion as a pipe 7. Molten Cu is sucked, through a pipe 13, by application of vacuum to the pipe 7, into the pipe 7 from a vessel 12, to be solidified by external cooling. Both vessels 1 and 12 may have a vacuum or protective atmosphere over the molten metal and an inert or reducing atmosphere may be maintained in the mould. The pipe 7 may be oval, circular, rectangular, triangular, starshaped, sector-shaped or trilobal in cross-section or be finned. The inclination of the pipe 7 may be varied from horizontal to vertical by changing the inclination of the extruder 3 or by bending the pipe. Instead of a wholly continuous extruder 3, an hydraulic machine may be used for batch operation. Pb may be east in a Pb pipe to form a composite casting. Al, Cu and Fe are also considered for the casting and the extruding. The filling of the pipe with metal to be cast may maintaining a particular pressure difference between the interiors of the pipe and the vessel 12 and the filling may be observed by measuring the resistance between points on the outer surface of the pipe 7, by ultrasonic waves or by a cog wheel pressed against the pipe and rotating with its progress to indicate irregularities by indentations on the pipe.