| 摘要 |
<p>PURPOSE:To cool a hot steel sheet uniformly in the length direction in the same way that the hot steel sheet passes at a certain speed through an on-line cooling device by controlling infection and interruption of plural headers for cooling refrigerant after the hot steel sheet stops in the on-line cooling device. CONSTITUTION:In an application rolling pass for cooling the hot steel sheet 2 immediately after it is rolled by a hot mill 1, stop control of the hot steel sheet 2 is started from a mill fin flaw signal. After a specified time is counted from the same mill fin flaw signal, control of interruption of refrigerant in the upper and lower cooling headers 8 (i), 9 (i) mounted on the position farthest from the mill in the cooling headers of the rear on-line cooling device 3 wherein refrigerant arranged on the outlet side of the mill is being injected is started. The control of interruption is transferred to the cooling headers on the side near the mill in sequence at a specified interval. In this way, uniform cooling is accomplished in the longitudinal direction of the hot steel sheet and rolling capacity can be prevented from reducing.</p> |
