PRODUCTION OF COMPOSITE INGOT IN CONTINUOUS CASTING STAGE

摘要

PURPOSE:To obtain a large-sized composite ingot having stable quality by executing descaling and secondary cooling or local holding and heating to maintain the temp. at both ends of the hot ingot at the temp. equal to or higher than the temp. in the central part, then dropping and laminating a different molten metal thereon. CONSTITUTION:The continuous hot ingot 4 formed by a tundish 2 and a casting mold 3 from a ladle 1 is descaled by a steel wire brush 6 in a chamber 19 in an inert gaseous atmosphere. The ingot 4 is subjected to secondary cooling under controlled secondary cooling conditions or to local holding or heating by using edge heaters 10 in such a manner that the temp. at both ends on top of the ingot 4 is made equal to or higher than the temp. in the central part. The molten metal 11 having the compsn. different from the compsn. of the ingot 4 is thereafter dropped from a dispersion nozzle 14 onto the ingot 4 by which the 2nd layer metal 16 is laminated on the ingot 4. Both metals are surely joined by hold-down rolls 17. The large-sized composite ingot having the stable quality is thus produced.