| 摘要 |
<P>PROBLEM TO BE SOLVED: To further extend the life of a dip tube while reducing trouble such as vacuum failure or suction of slag without increase in refractory thickness in vacuum degassing of molten steel using a circulating vacuum chamber. <P>SOLUTION: When a gas component in molten steel is removed by immersing dip tubes 5, 6 provided in a vacuum chamber in the molten steel stored in a ladle 7 and circulating the molten steel between the vacuum chamber and the ladle 7 while maintaining the dipping depth of the dip tubes 5, 6 by moving up and down the ladle, the level of slag surface in the ladle 7 is measured by a microwave level meter 8 during the circulation of the molten steel, and based on this measurement result, the distance L between the lower end surfaces of attachment flanges of the dip tubes and the slag surface of the slag in the ladle is maintained in the range of 100-200 mm. <P>COPYRIGHT: (C)2012,JPO&INPIT |
