| 摘要 |
PURPOSE:To improve production yield of casting billet by dipping a molten steel enclosing frame having the upper and the lower partition plates into a part, which is not yet solidified in the pouring molten steel, and inserting a submerged nozzle in the enclosing frame, under blowing inert gas from the upper partition plate. CONSTITUTION:The molten steel enclosing frame 1 consists of the upper partition plate 2, the lower partition plate 3 and a connecting member 4 between both plates. The upper partition plate 2 arranges the submerged nozzle inserting hole 5 and the inert gas blowing hole 6 for Ar gas, etc., and weir 7, which prevents added powders from the flowing loss around the inserting hole 5 thereon. At finishing of pouring for the first molten steel under condition of the presence of the molten steel, which is not yet solidified, the molten steel enclosing frame 1 is dipped from the lower partition plate 3. Next, the molten steel of a different kinds if poured from new tundish exchanged through the submerged nozzle inserted to the inserting hole 5. Then, inert gas is blowed from the blowing hole 6 to prevent oxidation by air. In this way, both molten steels are surely joined at a joint part, and the production yield of casting billet is improved.
|
