| 摘要 |
<p>PROBLEM TO BE SOLVED: To remove the skid mark by providing a header having a plurality of water injection nozzles between preceding stage stands and executing opening/ closing of nozzles with a solenoid valve so as to partially cool a rolling stock. SOLUTION: Between preceding stage stands of a hot finishing mill, plural cooling water headers 7, in which plural cooling water injection nozzles 8 are arranged in the width direction at a prescribed interval, are arranged at a prescribed interval. A three way selector solenoid valve 22 connected to an air supply pipe 23 and air exhaust pipe 24 is arranged at the upper part of header 7. By switching the three way solenoid valve 22 to switch air supply to a cylinder chamber 18 and supply air, a stop valve 15 closes a cooling water passage 13 by compressing a coil spring 19 to be switched to air exhaust and a cooling water passage 13 is opened. By this method, on/off of cooling water injection from the cooling water injection nozzles 8 to rolling stock is executed in high response, the rolling stock is partially cooled, the skid mark of rolling stock is removed.</p> |
