CONSTRUCTION IN TUNDISH NOZZLE PART FOR CONTINUOUS CASTING OF HORIZONTAL TYPE

摘要

PURPOSE:To obviate the generation of the damage and failure in the nozzle part having a double-stepped construction and the defect on the surface of a billet and to perform stably casting by forming a dense and smooth refractory material layer on at least the perpendicular surface of a tundish nozzle of said nozzle part of the respective perpendicular surfaces of the tundish nozzle and refractories for connection. CONSTITUTION:A tundish nozzle 1 is formed of zircon refractories and refractories 2 for connection are formed of a simple substance of borone nitride. The void volume of the refractories 2 is made about <=5%. Zirconia is deposited by plasma melt spraying on the perpendicular surface 1a of the nozzle 1 to about 200mu thickness whereby a refractory material layer 4 is formed. The nozzle 1 and the refractories 2 as well as the refractories 2 and a casting mold 3 are joined by a known means. If the nozzle part is constructed in such a way, the layer 4 remains nearly in the defect-free state after casting, by which the damage on the nozzle 1 is prevented and a cast billet is produced satisfactorily.