Method of manufacturing hollow metal ingots

Abstract

In the manufacture of hollow metal ingots, particularly for producing seamless tubes, the liquid melt is poured rapidly into an upright or slightly inclined chill mould, the chill mould is closed and is tilted into a substantially horizontal position in which it is slowly rotated about its longitudinal axis. The hole is produced in the hollow ingots by pouring into the chill mould a quantity of melt which corresponds to the total volume of the chill mould plus the shrinkage volume and less the volume of the desired hole. The method is particularly advantageous when manufacturing hollow ingots of great length, although the method can also be used when manufacturing short hollow ingots. It is particularly advantageous to blow in an accurately dimensioned quantity of inert gas, corresponding to the hole in the hollow ingot, during and after the actual pouring operation.

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