Factors Affecting the Formation of Shell and Longitudinal Cracks in Mold during High Speed Continuous Casting of Slabs

Factors affecting the formation of shell and longitudinal cracks on the shell have been investigated for high speed continuous casting of slabs.Withdrawal speed of slab, stream velocity from submerged nozzle, mold taper, and mold oscillation have shown respective influence on the formation of shell. Their effects have been analyzed quantitatively. Also, characteristics of the heat extraction from and resulting stress in the shell have been examined with respect to the crack formation.These observations have resulted in countermeasures to enhance uniform shell formation in mold and prevent the cracks on the slabs.