METHOD FOR PREVENTING LONGITUDINAL CRACK ON SOLIDIFIED SHELL SURFACE IN CONTINUOUS CASTING MOLD

摘要

PURPOSE:To prevent breakage and to continuously cast a medium carbon steel by flowing molten steel at limited speed along inner circumferential face of solidified shell in the range of at least the specific distance from just below meniscus in a mold. CONSTITUTION:The mold is composed of short sides 2 having mold with changeable device 3, long sides 1 forming mold pool as inserting the short sides 2, mold traverser 4 guiding slide shift for the long side 1 and an electromagnetic stirring device 7 set in water cooling boxes 5 for the long sides 1. At the time of casting a cast slab at =1.0m/min casting speed by pouring the molten medium carbon steel containing 0.1-0.18% C into this mold, by flowing the molten steel with the electromagnetic stirring device 7 arranged on the mold at 40-120 cm/sec speed along the inner circumferential face of the solidified shell in the range of at least 20mm from just below the meniscus in the mold, the slab 11 having surface layer part quality without any longitudinal crack can be drawn from the mold.