Abstract:To optimize the mold nozzle during the slab continuous casting process to suppress slag entrapment, a three-dimensional model of the stainless-steel slab continuous casting mold was established using ProCAST to study the optimization method of the mold nozzle. By measuring the performance parameters of the protective slag using a laboratory viscosity meter and incorporating them into the empirical formula for the critical surface flow rate of slag entrapment, the critical surface flow rate of molten steel that is prone to slag entrapment can be obtained. Numerical simulation calculates the critical surface flow rate of molten steel before and after optimization, as well as the flow field and temperature field of the mold. The theoretical value of the critical surface velocity of molten steel slag is 0.35 m/s. The numerical simulation results show that the diameter of the middle hole increases from 55 mm to 60 mm, the inclination angle of the side hole decreases from 8 ° to 6 °, the critical surface velocity of the steel in the four feet casting billet decreases from 0.347 m/s to 0.296 m/s, and the critical surface velocity in the five feet casting billet decreases from 0.351 m/s to 0.323 m/s. Under the optimized parameters, the surface flow rate of the molten steel is appropriate, the flow field and temperature field of the mold are reasonable, which is conducive to the melting of the protective slag. The lubrication effect of the billet shell is good, and it can effectively suppress the occurrence of slag entrapment. Therefore, the nozzle of the slab continuous casting mold can be optimized according to this parameter.
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