| 摘要 |
PURPOSE:To promote the slagging of powder and to improve the surface quality of a cast slab by developing ascending flow in molten metal by acting electromagnetic force to the molten metal poured into a mold from a nozzle at the initial stage of casting and increasing the heat supplying quantity to the powder supplied on the upper part of molten metal. CONSTITUTION:The molten steel 10 is poured into the mold 2 from a tundish, as a dummy bar head 18a is descended. And, when the dummy bar head 18a has reached at the lower end of mold 2, the electromagnetic force is acted to the molten steel 10 in the mold 2 by electric magnets 14a-14d. Then, the ascending flow is developed in the molten steel 10 toward the arrow mark (b) direction and discharging flow C from discharging holes 8, 8 is flowed upward to stir the molten steel 10. Therefore, the heat supplying quantity to the powder 20 supplied on the upper part of molten steel 10 is increased, and so the slagging of powder 20 is promoted, and defect caused by inclusion in the cast slab is not developed by intervention of the powder 20 in solidified shell 24 at meniscus part 22. |
