DIPPING NOZZLE FOR CAST STEEL

摘要

PURPOSE:To extend the useful life longevity of a nozzle by forming the projection having an inclined face from the upper end of the discharging port of the molten steel stream of a nozzle and regulating the shape dimension and inclination thereof in the specified dimensional and angular ranges. CONSTITUTION:The projection 4 having a regular inclined face from the opening hole end of the upper end part of the discharging port 2 of a nozzle main body 1 is formed. In this case, the height A of the projection 4 is regulated within the range of 5-50mm from the nozzle external face and the height B is regulated in the range of 10-200 mm. Moreover the inclination C for the horizontal plane from the apex of the projection 4 is regulated in the range of 5-60 deg.. Accordingly, the directions of an argon gas bubble stream 3 and molten steel stream 5 are adjusted and the floating position of the bubble stream 3 is moved to the position apart from a nozzle powder 6. The wear of the nozzle 1 accompanied by the volume expansion and rupture of the bubble stream 3 is reduced and the useful life longevity of the nozzle is extended.