METHOD FOR REDUCING TOP CROP IN CONTINUOUS CASTING

摘要

PURPOSE:To decrease the amt. of top crop and to improve yield by increasing feed speed and rolling down the top part which is secondarily cooled and is not yet fully solidified owing to interruption of continuous casting by as much as the shrinkage on solidification in a secondary cooling zone after a skin is formed on the bath surface. CONSTITUTION:The feed speed of a device is increased and a billet 1 is fed to a horizontally cooling zone at the point of the time when a skin 2 is formed on the bath surface in the top part 3 which is secondarily cooled and is not fully solidified yet in the stage of an interruption of continuous casting. The billet is rolled down by as much as the shrinkage on solidification in the top part by screw-down roll groups 11 or pinch rolls 13 in the secondary cooling zone to shorten the unsolidified part and to decrease the amt. of the top crop to be cut off. The yield of the billet 1 is improved by the above-mentioned method.