Patent ID: 7762311

Claim:
A method for controlling a flow of a molten steel by applying a shifting magnetic field to the molten steel in a slab continuous casting machine comprising: controlling a molten steel flow velocity on a molten steel bath surface 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 on the molten steel bath surface is higher than a mold-powder entrainment critical flow velocity; controlling the molten steel flow velocity on the molten steel bath surface to a range of from an inclusion-adherence critical flow velocity or more to a mold-powder entrainment critical flow velocity or less by applying a shifting magnetic field to rotate the molten steel in a horizontal direction when the molten-steel flow velocity on the molten steel bath surface is lower than the inclusion-adherence critical flow velocity and a bath-surface skinning critical flow velocity or more; and controlling the molten steel flow velocity on the molten steel bath surface to the range of from the inclusion-adherence critical flow velocity or more to the mold-powder entrainment critical flow velocity or less by applying a shifting magnetic field to impart an accelerating force to the discharge flow from the immersion nozzle when the molten-steel flow velocity on the molten steel bath surface is lower than the bath-surface skinning critical flow velocity.