| 摘要 |
PURPOSE:To uniformly generate heat in a nozzle body to prevent solidification of a molten steel by combining resistance exhothermic refractories and high resistance refractories to form the nozzle body and allowing the resistance exhothermic refractories to generate heat when current bypasses the high resistance refractories. CONSTITUTION:This electrical heating nozzle is made into inside and outside two-layered structure consisting of the resistance exhothermic refractories 10', 10 and the parts of the proper width from an upper port 2 to a molten steel outflow port 3 only in the angle position at each end of the diameter of the nozzle 1 are made of the high resistance refractories 11, 11. The resistance exhothermic refractories 10, 10', therefore, face each other with the high resistance refractories 11, 11 in-between. Said refractories are united and are electrically connected to each other at the bottom end of the nozzle where the high resistance refractories do not exist. The resistance exhothermic refractories 10' on the inside periphery are magnesia- graphite refractories and the resistance exhothermic refractories 10 on the outside periphery are alumina-graphite refractories. The area of the part where the resistance exhothermic refractories 10 on the outside periphery contact a powder line 4 is zirconia-graphite refractories and the high resistance refractories 11 are alumina-trace graphite refractories. Electricity is supplied from a solderless electrode 5 at the top end of the resistance exhothermic refractories on the outside periphery. |
