| 摘要 |
PURPOSE:To prevent a temp. drop of molten steel by dividing a nozzle into two parts with a electrically insulating gap and, by forming a resistance type heat generating layer at the central part of a molten-metal-flow path and, by forming an electrically insulating layer at the inside of said path, and by making a heat generating layer heatable. CONSTITUTION:A main nozzle body 1 is constituted of electrically conductive refractory material, the inner part of which is divided into two parts with a gap 2 formed in the vertical direction, to be electrically insulated. A resistance type heat generating layer 3 is formed at the central part of the molten metal flowing path of the nozzle 1 and is heated by applying electrical current from a heating electric source 5 through a lead wire 4, connected to the body 1. Besides, an electrically insulating layer 6 is formed at the inside of the molten metal flowing path to prevent a temp. drop of the molten metal caused byheat transmission while the molten metal passes through the nozzle 1, and to prevent a solidification of the molten metal during casting in the inside of nozzle 1 which cause a casting impossible. Furthermore, the applied electric current is prevented from flowing through the molten metal by the aid of the insulating layer 6. |
