| 摘要 |
<p>PURPOSE: To control with high precision a target coiling temp. in the case where water injection quantity rapidly changes against a virtual cut plate due to a large fluctuation in FDT and passing speed. CONSTITUTION: In cooling a rolled sheet S finished in a hot rolling process by forwarding the rolled sheet S into a cooling equipment 12, injecting it with cooling water from a water injecting header arranged in the cooling equipment and cooling it to a prescribed coiling temp.(CT), the injecting quantity of the cooling water is estimated, for each virtual cut sheet set for the rolled sheet S, based on the measured temp. on the exit side of a finishing mill (FDT) and on a preliminarily set passing speed. Then, in the coiling temp. control method in which the water quantity thus estimated is injected on the virtual cut sheet, the water quantity corrected against the FDT fluctuation and the water quantity corrected against the speed fluctuation are separately determined and, by correcting the former in the FDT zone 12A and correcting the latter in the speed zone 12B, a rapid change in the water injection quantity is dealt with.</p> |
