| 摘要 |
PURPOSE:To close and open easily a tundish nozzle by generating forcibly a nozzle cross by a billet in the inlet part of the tundish nozzle to close said nozzle and removing the billet by an O2 lance set to the top end of a dummy bar to be inserted into a mold to open said nozzle. CONSTITUTION:Closing of a tundish nozzle 1A is accomplished by forcing a billet spear 5A into the nozzle in a molten steel from above a tundish 2. Oopening of said tundish nooozzle is accomplished by providing a metallic connector 14 coupled to the billet 5a to the top end of a dummy bar 13 inserted into a mold 3, providing a tubular passage 15 at the center of both bar 13 and connector 14 and disposing a fluid supply pipe 16 therein. For example, O2 is thereupon blown from the rear of the bar 13 to melt the billet closing the spear 5A, thereby opening the nozzle 1A. |
