| 摘要 |
<p>PROBLEM TO BE SOLVED: To secure a target finishing exit side temperature in especially the leading end portion of a material to be rolled by appropriately controlling a cooling water volume to cool finishing stand spaces and a cooling water volume to cool work rolls when the finish rolling in the manufacture of a hot-rolled steel plate is performed. SOLUTION: In the finish rolling by the finish rolling mill provided with the stand space cooling means and the work roll cooling means, when the threading speed of the leading end of the material to be rolled and the initial value of the stand space cooling water volume are set up, the upper limit value of the threading speed and the lower limit value of the stand space cooling water volume are set to each initial value and the initial value of the work roll cooling water volume is decreased from the cooling water volume during a steady state rolling operation, in case that the threading speed and the initial value of the stand space cooling water volume calculated in order to secure the target finishing exit temperature of the leading end portion are not within the scope of each upper and lower limit value predetermined. When the rolling speed is increased after the leading end is threaded, the cooling water volume of the work roll are increased to the volume required during the steady state rolling operation and then, the stand space cooling water volume is increased.</p> |
