| 摘要 |
PURPOSE:To prevent the occurrence of breaking lines on the outside circumferential surface of an ingot by forming the head part of a pouring nozzle into a truncated cone, and opening a supply hole for molten slag on the way of the cone. CONSTITUTION:Upon starting of casting work, the molten slag 13 in a airtight tank is supplied into a mold through a supply hole 15 opened on the slope S of the head part 4' of a pouring nozzle 4. The molten slag 13 in the clearance C between the tread surface of an endless track and the flat part T of the nozzle 4, and the part near the same forms a solidified layer U of a wedge shape in section stuck on the slope s, thereby preventing the slag 13 from leaking to the outside through the clearance C. The slag layer carried along with the shifting of the tread surface is broken at the leading end part V of the solidified layer U, and the molten slag 13 in a well W immediately infiltrates the broken part of the slag layer and is carried without disconnection while reproducing fresh solidified shells. On the other hand, the molten steel 1 in the mold is cooled while forming one partition wall of the well W of the molten slag 13, thereby successively and continuously forming solidified shells 6. Hence, inscribing of breaking lines does not occur. |
