| 摘要 |
PURPOSE:To provide a cooling device of improved uniform cooling and cooling capacity for hot-rolled steel sheets by providing plural slit nozzle for supplying cooling water provided with angles so as to spread in the width direction of the steel sheet with respect to the advancing direction of the steel sheet after hot rolling. CONSTITUTION:While a steel sheet 3 after hot rolling is traveling in an advancing direction 4 at a predetermined cooling speed, cooling water is dropped in the form of film from slit nozzles 10 onto the steel sheet 3, so that the steel sheet 3 is cooled. In this case, the cooling waer 12 is first flowed in the width direction of the steel sheet 3 at the front face of the cooling water film 11 falling from the nozzles 10 onto the steel sheet 3 under traveling, thence it is flowed between the water films 11 along the advancing direction 4 of the steel sheet 3 so as to prevent the thickness of the water films from increasing. Hence, disturbing of the collision of the water films 11 dropping in succession onto the steel sheet 3 against the steel sheet 3 does not occur and the decrease in the cooling capacity for the steel sheet 3 is prevented. It is necessary to set the above-described nozzles 10 at angles of 45-90 deg. with respect to the advancing direction of the steel sheet 3. |
