GB1373404A - Method and machine for continuous centrifugal casting of hollow shapes - Google Patents

Abstract

1373404 Continuous centrifugal casting; flame cutting L DANIELI 15 Oct 1971 [2 March 1971] 48148/71 Headings B3F and B3V A hollow body is cast continuously and centrifugally in a (copper) mould 8 which is inclined upwardly or downwardly or is horizontal, is cooled (as by a non-rotated water jacket 10), and is oscillated longitudinally, the casting being withdrawn (as by a rotated ring of rollers 33). At the inlet end of the mould 8 is a cemented refractory lining (7) with a diverging bore into which extends a tundish nozzle. The valved tundish may have several nozzles each extending into one of the moulds of a number of parallel casting units. The mould 8, which may have an inner taper towards its outlet, is rotated by a sprocket (11) at the outlet end driven by a chain (23). There may be an inner, perforated, water jacket 9 rotated with the mould and its perforations may be shaped to draw water in at the rear end and pump it back into the jacket 10 at the front. In this case, the horizontal partitions indicated in the jacket 10 in Fig. 1A, are replaced by vertical transverse partitions. There may be impeller blades or fins mounted on or in the jacket 9 or on the mould 8 or a screw-like formation in the jacket or on the mould. The jacket 10 has a sliding guide, or wheels (18) running on a track (19), and is driven back-and-forth by a rod 20 to oscillate the mould structure. Oil or powdered slag lubricant is distributed around inside the mould inlet. In a secondary cooling stand, the rotating cast strand may be supported, on balls 40 or rolls. There may be such supporting-balls at the outlet of a withdrawal unit, which carries at the inlet end of a tubular roll-carrier (31) rotated by the mould-rotating motor (27), a cage 32 of rolls 33 which may be loaded by springs 35, Fig. 1C, with an electric pressure release system, or by a motorized screwdown system or electromagnetic linear actuators. The rolls 33 may be driven at a variable rate from a single motor or individual motors 36. The stand (45) of an oxygen cut-off torch (46) has supporting-balls (44) and is rolled on a track (49) by a mechanical device or hydraulic cylinder (48). The torch is drivable transversely of the casting path. For handling the cut-off lengths and a starter bar (51), there is a stand (52) of rolls (53) of hyperboloid shape oblique to the casting path and driven electromagnetically. A similar stand can be used as a withdrawal unit instead of the ring of rollers 33. The removable head (50) of the rigid tubular starter bar (51) has coarse threading for joining to the cast metal. It is used with asbestos cord packing and scrap metal. The casting wall thickness is determined by the withdrawal rate, by the pouring rate or by both. The operator controls the pouring, withdrawal and rotation rates by direct observation of the mould cavity, or by periscope, optic fibre, television or from wall-thickness data recorded by X-ray or isotope measuring devices.