| 摘要 |
PURPOSE:To improve the life of rolling rolls by decreasing the flow rate of cooling water to the lowest density at the beginning of rolling contact, increasing the density during rolling and further continuously increasing the density during the standby the rolling. CONSTITUTION:The temp. change rate of the roll surface at the 1st rotation when the rolling rolls begin to contact with a material to be rolled is largest. The crack of the roll surface is consequently prevented if the temp. change rate of the 1st rotation at the start of rolling is set smaller than the max. impact temp. difference of the rolls and if the temp. change rate always is made smaller than the max. impact temp. difference even during rolling. More specifically, the density of the flow rate of the cooling water on the roll surface is made lowest at the start of rolling and is exponential-functionally increased even during the rolling. The density is increased up to the max. value even during the standby for rolling until the next contact by which the temp. change rate of the roll surface always is kept within the max. impact temp. difference. Since the generation of the crack, etc. is decreased, the life of the rolls is improved. |
