| 摘要 |
PURPOSE:To prevent intrusion of carbon into a molten steel in the stage of multiple and continuous casting of a dead soft steel by using carbonaceous refractories for the base body of a nozzle and forming via a separating layer a refractory layer without contg. carbon to the surface in contact with the molten steel. CONSTITUTION:Carbonaceous refractories having high corrosion resistance and high spalling resistance, for example, alumina graphite bonded with carbon or the like is used as a base material 1 and a refractory layer 4 having at least 2mm. thickness without contg. carbon is formed in the outside circumferential direction from an inside hole 2 where a molten steel passes. 80% of the contact surface between the layer 4 without contg. carbon and the material 1 is separated via a separating layer 5 to prevent cracking owing to heat hysteresis of both layers 1, 4. The nozzle for casting having such double-layered structure is less eroded in the bore and is suitable for casting of a dead soft steel. |
