Study on Behavior of Slag Entrapment in Mold for Slab Caster

摘要

The influence of casting speed, nozzle submergence depth and gas flow rate on three types of slag entrapment in the mold was investigated by physical simulation, and the occurrence frequency of slag entrapment was obtained through statistical method. The conditions and position for different types of slag entrapment were analyzed, and then, the penetration depth of slag droplets was observed. The results show that the slag entrapment caused by shear force is a common phenomenon at high casting speed, which is mainly affected by casting speed. The slag entrapment due to gas blowing would occur in mold with low casting speed and high gas flow rate, which is induced by big bubbles, and the slag droplets which have shallow penetration depth are easy to float up. The slag entrapment caused by vortex has something with the asymmetry flow rather than the process parameter, and the slag droplets are difficult to float up because of deep penetration depth. In addition, the relation between the penetration depth of slag droplets and nozzle submergence depth was discussed, and some measures to reduce slag entrapment were also presented.