IMMERSION NOZZLE FOR CONTINUOUSLY CASTING STEEL AND CONTINUOUS CASTING METHOD OF STEEL USING THIS NOZZLE

摘要

PROBLEM TO BE SOLVED: To intensify the stirring of molten steel in an immersion nozzle with a simple device and to promote equi-axed crystals in a continuously cast slab with the conduction of sensible heat of the molten steel by forming a part, in which the molten steel flows down in non-vertical state from a tundish at the intermediate part of the immersion nozzle. ;SOLUTION: The immersion nozzle 1 for continuous casting is provided with the non-vertical part 2 having 50-600mm length and 5-70° angle to the perpendicular line at the intermediate part. A gas blowing hole 3 for blowing inert gas of argon, etc., from the lower part of the non-vertical part 2 and a gas suction hole 4 enabling the suction of gas from the upper part of the non-vertical part 2, are provided. The upper part of the nozzle 1 set to the tundish and the part immersed into the molten steel in a mold 5 have the vertical structure. Therefore, the equi-axed crystals are stably developed and the segregation in the cast slab can be reduced. Further, additionally, since the flow-down of the molten steel can be relaxed, the segregation in the fluid in the mold 5 can be prevented.;COPYRIGHT: (C)1997,JPO