METHOD AND APPARATUS FOR CONTINUOUSLY CASTING STEEL

PROBLEM TO BE SOLVED: To improve the quality of a cast slab in continuous casting of steel by suppressing the variation of the quality of the cast slab by suppressing the generation of vortexes in the molten steel in the immersed nozzle. SOLUTION: A static magnetic field 20 having the magnetic flux density BB2satisfying the following expression, BB2≥C0Q/A, is applied, by an electromagnetic braking device 10, to the molten steel 4 in the immersed nozzle 3 existing at the same level as that of the discharge port 6 of the immersed nozzle 3, where BBshows magnetic flux density (T) in the static magnetic field 20; C0shows a constant; Q shows a mass flow (kg/s) of the molten steel 4, and A shows the inside cross sectional area (m2) of the immersed nozzle 3. The electromagnetic braking force is formed by the applied static magnetic field 20 so as to oppose to the drift current 21 of the molten steel 4 to flow in the immersed nozzle 3 in the neighborhood of the discharge port 6 in the immersed nozzle 3, and the drift current 21 is straightened. COPYRIGHT: (C)2009,JPO&INPIT