METHOD FOR PREPARING TUBULAR CHILLS FOR CONTINUOUS STEEL CASTING PLANTS

摘要

A method is described for the preparation of tubular copper or copper-alloy chills or ingot moulds shaped with their longitudinal axis substantially curved, and comprising a first stage in which the end of a tubular semi-finished product of rectilinear axis is turned-over by cold plastic deformation; a second stage in which said semi-finished product is shaped to give it a curved form; a third stage in which a mandrel having the same shape and outer dimensions as the chill to be obtained is then inserted into said semi-finished product; a fourth stage in which said semi-finished product is passed through an extruder die of such dimensions as to deform the material of said semi-finished product in order to cause the inner surface of said semi-finished product to adhere closely to the outer surface of said mandrel; and a fifth stage in which when said semi-finished product has passed through said die, a substantially axial force is exerted on said mandrel in the opposite direction to the force exerted in the preceding stage, while the end edge of said semi-finished product is rested against counteracting sectors disposed below said die.