| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a hot-rolled steel sheet which has specified stable mechanical properties and is excellent in surface properties at a low cost by controlling the temperature of the hot-rolled steel sheet at the inlet and the outlet of a finishing mill to the target value while suppressing the cost of equipment and the running cost which are necessary to a heating device and a cooling device as much as possible and also controlling the cooling conditions in the cooling process on a run out table to the target value. <P>SOLUTION: This method is a method for manufacturing the hot-rolled steel sheet 9 by heating a rough bar 1 after a slab 20 is made into the rough bar 1 by performing rough rolling, next, performing finish rolling, after that, performing water cooling and air cooling in order. The preset values of thickness of the rough bar 1 and the rolling speed of the finish rolling are corrected so that all of the inlet temperature and the outlet temperature in the finish rolling, cooling stopping temperature in the water cooling and air cooling time satisfy respective target values. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
