| 摘要 |
PURPOSE:To obtain a thick steel sheet with less internal defects by disposing a forced cooling device of rough rolled material at the specific position on a rolling line, in a thick sheet rolling line. CONSTITUTION:In a thick sheet rolling line 3 consisting of a heating furnace 1, a roughing mill 2, a finishing mill 5, and a refining line, etc., a forced cooling zone 4 is disposed on the line 3 between the mills 2, 5 and adjacently to the mill 5. A billet discharged from the furnace 1 is rough rolled by the mill 2 and is immediately conveyed to the zone 4 to cool it to a prescribed temperature. The rough rolled material provided with the temperature distribution in the sheet-thickness direction by the forced cooling, is conveyed on the line 3 to the mill 5 immediately before losing its temperature distribution by heat recovery, and is finish rolled. In this way, a steel sheet with excellent toughness and less internal defects is obtained. |
