GB1348479A - Level control in continuous casting - Google Patents

Abstract

1348479 Continuous casting BRITISH STEEL CORP 24 June 1971 [24 June 1970] 30546/70 Heading B3F [Also in Division G3] A solidified casting is continuously extracted (e.g. a tube drawn upwardly with the aid of a starter tube 25) from a mould 8 communicating (as by a nozzle 7) with a melt-containing vessel 5 in which a pressure-sensitive device 10-15 is at least partly disposed, to detect pressure changes at a position in the melt 6 and to govern a control by which the melt pressure at the mould inlet is kept constant. As shown, the vessel 5 is a ladle in a pressure chamber 1 to which, in order to raise the melt 6 into the mould 8, air or inert gas is supplied through an inlet 3 by way of a valve 21 operated by a controller 18 governed by a differential-pressuremeasuring instrument 14 of the pressure-sensitive device to maintain the metal level S in the mould 8. The detector of the pressure in the melt 6 is a dip tube 10 with an open end in the melt and through which argon is passed from a valve 11 and a constant flow and pressure device 12. Instead of maintaining the melt level S by supplying gas to the chamber 1, it may be done by introducing more molten metal into the vessel 5 or by varying the relative positions of the mould 8 and vessel 5. In the apparatus shown, a fail-safe arrangement 23, 24 operates a valve 17 to release the gas pressure in the chamber 1 if the pressure in the dip tube 10 falls suddenly. The second differential-pressure-measuring instrument 23 indicates the melt level in the ladle 5.