| 摘要 |
PROBLEM TO BE SOLVED: To obtain cast metal with less center segregation over its entire width and less V segregation near the thickness center by reducing thickness by the quantity equivalent to bulging or less with a concave reducing roll pair whose center of the roll barrel is smaller than the roll end portion in roll diameter till the completion of solidification after the cast metal including an unsolidified portion is bulged by a specific dimension or more. SOLUTION: Cast metal including an unsolidified portion is bulged by 10 mm or more at the center in the width direction, and then reduced with a reducing roll pair 4-1. The portion near the short-side portion on both sides is reduced more, and made to be less in thickness than the center in the width direction, and the thickness of an unsolidified portion 2c near the short-side portion on both sides becomes almost the same as that of an unsolidified portion 2b at the center in the width direction. This makes it difficult for the molten metal with concentrated segregation component existing in the unsolidified portion 2b to run into the unsolidified portion 2c, and the molten metal with concentrated segregation component existing in the unsolidified portions at the center in the width direction and near the short-side portion on both sides is all discharged to the upstream side in the casting direction.
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