| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a continuously cast slab, which prevents a recessed part of a pressed-down surface of a continuously cast slab manufactured by a continuous casting apparatus from remaining in a steel piece after blooming as a surface defect. <P>SOLUTION: At a cross-section vertical to the casting direction at a position where a pressing-down roll 3 having a protruding part 4 whose width is narrower than that of a continuously cast slab 1 being drawn from a continuous casting apparatus comes into contact with the continuously cast slab 1, a rise angle θ<SB POS="POST">1</SB>formed by an inclined surface 5 of the protruding part 4 protruding obliquely from the pressing-down roll 3 and the surface of the continuously cast slab 1 that comes into contact with the horizontal surface of the protruding part 4 is set so as to satisfy 5°≤θ<SB POS="POST">1</SB>≤15°, and a supplementary angle θ<SB POS="POST">2</SB>of the rise angle θ<SB POS="POST">1</SB>of the inclined surface of the protruding part 4 of the pressing-down roll 3 is increased to the rise angle θ<SB POS="POST">1</SB>so as to satisfy 165°≤θ<SB POS="POST">2</SB>≤175°, the continuously cast slab 1 being drawn from the continuous casting apparatus is pressed down by the protruding part 4 of the pressing-down roll 3 to form a recessed part 2, and further, by subjecting the continuously cast slab 1 to blooming, the generation of surface defects on the steel pieces after blooming is eliminated. <P>COPYRIGHT: (C)2013,JPO&INPIT |
