| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable to improve the use frequency of a molten steel pan. <P>SOLUTION: When a secondary refining treatment that uses electrode heating for a molten steel is performed, the estimated remaining thickness of a slag line refractory 3c is calculated by using the dissolution loss speed of the slag line refractory 3c obtained based on the energization electric power consumption rate when electrode heating is performed. The estimated remaining thickness when the slag line refractory 3c becomes the application limit is set based on the result remaining thickness and the estimated remaining thickness of the slag line refractory 3c. At least two management regions where the change of the bath level of the molten steel is allowed to a slag line part 6 of the molten steel pan 1 are set. In addition, the amount of the tapping is set so that the molten steel bath level may become in the control regions when tapping the molten steel in the molten steel pan 1. The molten steel is charged into the molten steel pan 1 based on the amount of the tapping, the secondary refining treatment is performed, and when the estimated remaining thickness of the slag line refractory 3c in the management region reaches the estimated remaining thickness when becoming the application limit after the treatment of the secondary refining, the end point of molten steel pan 1 is made. <P>COPYRIGHT: (C)2013,JPO&INPIT |
