| 摘要 |
PURPOSE:To reduce sticking of inclusions to a delivery passage for molten steel by forming an angle at the upper margin of the molten steel delivery passage of a nozzle to the horizontal direction larger than at the lower margin of it to the horizontal direction. CONSTITUTION:The upper end part of the submerged nozzle 18 is fitted at a bottom of a tundish 16 and the lower end part 20 thereof is submerged into the molten steel in a mold 14. The molten steel passage 22 is formed in the nozzle 18 and the molten steel delivery passage 24 connected with the passage 22 is formed at the lower end part 20 of the passage, to form the angle (B) at the upper wall 32 thereof to the horizontal line 30 larger than the angle (A) at the lower wall 26 thereof to the horizontal line 30. In this way, the molten steel flowing speeds at near the lower wall 26 and at the upper wall 32 make to be almost the same flowing speed. Therefore, the inclusions in the molten metal, such as Al2O3, etc., sticking to the molten steel delivery passage 24 are reduced. |
