PRODUCTION OF NOZZLE FOR CASTING MOLTEN STEEL

摘要

PURPOSE:To produce a nozzle for casting a molten steel having a circular hollow part for blowing gas by embedding concentrically with a core a cylindrical expendable material formed by winding spirally the same in a refractory material in a molding flask and subjecting the material to rubber pressing then to calcination. CONSTITUTION:An expendable belt-like sheet 7 is spirally wound around a circular cylindrical core and the superposed part is fixed by means of an adhesive agent; the thickness is adjusted by the degree of the superposition, whereby a cylindrical expandable material 5 is formed. A refractory material is charged into a molding flask made of rubber having a core and at the same time, the material 5 is inserted concentrically with the core therein and is embedded in the refractory material. The rubber mold is put in a liquid pressure vessel and is molded by rubber pressing. The molding is calcined at a high temp. after drying and a nozzle for casting molten metal having a circular hollow part 3 for blowing gas communicating with a gas introducing pipe 4 in a nozzle body 1 having a nozzle hole 2 is obtd. A non-woven fabric consisting of org. fibers such as ''Vinylon'' fiber or the like is adequately usable as the above-mentioned material 5.