| 摘要 |
PURPOSE:To safely treat the final billet without generating void by stopping drawing out billet when the molten steel level in the tundish reaches the specified level, charging the tundish with a heat insulating material, and discharging residual molten steel after a specified period of time and before solidification occurs in the feed nozzle. CONSTITUTION:When the tundish 1, mold 3, pinch roller 4 and other components to draw out fillets 5 intermittently draw the final billet, that is, when the molten steel level in the tundish 1 reaches the specified level, pinch rollers 4 stop drawing out billets, and immediately the tundish is charged with a heat insulating material 11. After a period of time defined by the equation t>=3X10<-4>XD<2> where T: time (min) waiting for solidification and D: billet diameter (mm) or minor axis instead if fillet has a flat cross section, and before solidification occurs in the feed nozzle, the cylinder 6 is actuated to open the valve 7 and discharge remaining molten steel in the tundish 1 to the ladle 9. Thereafter, billet 5 is separated from the solidified steel in the tundish 1 by the cylinder device 10. |
