Numerical Simulation of Influence of Casting Speed Variation on Surface Fluctuation of Molten Steel in Mold

Abstract

The influences of casting speed variation on surface fluctuation of the molten steel in mold during continuous casting were investigated with numerical simulation method. It was found that when the casting speed was evenly decreased from 1.4 m • min⁻¹ to 0.6 m • min⁻¹, the increase of the surface fluctuation of the molten steel in mold was observed only on time that was at the start of casting speed change. While, in experiment of increasing casting speed evenly from 0.6 m • min⁻¹ to 1.4 m • min⁻¹, the increase of the surface fluctuation of the molten steel in mold was observed only at the time when the casting speed was stopped to increase after it had been increased to 1.4 m • min⁻¹. For surface fluctuation of the molten steel in mold which was produced during the casting speed evenly increasing or decreasing period and at the time when increasing or decreasing the casting speed at low casting speed level (0.6 m • min⁻¹ ), the influence of casting speed change is very small. In addition, it is found that, at high casting speed level (1.4 m • min⁻¹), even a little change of casting speed could result in remarkable increase of the surface fluctuation. Thus, at high casting speed, changing casting speed should be avoided or much slower speed changing rate should be used.