METHOD AND APPARATUS FOR CONTROLLING FLOW OF MOLTEN STEEL IN MOLD, AND METHOD FOR PRODUCING CONTINUOUS CASTINGS

摘要

When a molten steel flow velocity (u) on a bath surface is higher than a mold-powder entrainment critical flow velocity of 0.32 m/sec, the molten steel flow velocity (u) is controlled to a predetermined molten steel flow velocity by applying a shifting magnetic field to impart a braking force to a discharge flow from an immersion nozzle. When the molten steel flow velocity (u) is lower than an inclusion-adherence critical flow velocity of 0.20 m/sec and is higher than or equal to a bath-surface skinning critical flow velocity of 0.10 m/sec, the molten steel flow velocity (u) is control to the range of 0.20-0.32 m/sec by applying a shifting magnetic field to rotate the intra-mold molten steel in a horizontal direction. When the molten steel flow velocity (u) is lower than the inclusion-adherence critical flow velocity, the molten steel flow velocity (u) is controlled to the range of 0.20-0.32 m/sec by applying a shifting magnetic field to impart an accelerating force to the discharge flow from the immersion nozzle.