| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for producing an extra-low sulfur steel by which the molten steel having≤14 ppm sulfur concentration can be produced in a simpler method and at lower cost than the conventional method. <P>SOLUTION: The molten steel produced through a pre-desulfurizing treatment of molten iron and a decarburization-refining in a converter is tapped into a ladle from the converter, and flux for CaO-base refining and Al are added and thereafter, stirring is performed by blowing inert gas below the molten steel surface under ordinary pressure, and when the extra-low sulfur steel is produced, the above ladle is shut off from the atmosphere with a cover, and while holding oxygen concentration under atmosphere at a free-board part between this cover and the molten steel surface to≤10 vol%, the stirring is performed by blowing the inert gas. <P>COPYRIGHT: (C)2004,JPO</p> |
