CONTINUOUS CASTING METHOD FOR ROUND CAST BILLET

PURPOSE:To improve the quality of a cast billet by suitably setting depth of a submerged nozzle in accordance with electromagnetic stirring force, casting velocity and powder characteristic in continuous casting method, which executes a powder casting while stirring by the electromagnet. CONSTITUTION:At the time of casting, which executes the powder casting while stirring the round cast billet by the electromagnet, beforehand the optimum depth of submerged nozzle is set based on the electromagnetic stirring force, casting velocity and the characteristics of viscosity, melting point, etc., of the powder in every sizes for the cast billet. Limit of phenomenon, which the molten powder is drawn down near the submerged nozzle, is decided by the depth of the submerged nozzle and rotating flow velocity of the molten steel near at the meniscus. Further, in case the depth of the nozzle is too deep, melting heat of the powder is insufficient and poor lubrication between a mold and solidified shell is developed. As the depth of the submerged nozzle is always held to the optimum depth, the thickness of the powder layer is suitably maintained and the development of surface fault in the cast billet is reduced and the quantity of the cast billet is improved.