| 摘要 |
PURPOSE:To widen the optionality of the sheet shape control, and to obtain a product in good quality, by making the length of effective surfaces of upper and lower backup rolls shorter than the length of effective surface of an intermediate roll and a work roll, and by permitting upper and lower bending devices to work independently of each other. CONSTITUTION:The length l1 of the effective surface of an upper backup roll 5 is made different from the length l2 of effective surface of a lower backup roll 7; the effective surface length l1 is made shorter than the length of effective surface of an upper work roll 1, and the effective surface length l2 is made shorter than the length of effective surface of a lower work roll 3. The diameter of the upper work roll 1 is made small; an intermediate roll, whose effective surface length is longer than that of the upper backup roll 5, is arranged between the upper work roll 1 and the upper backup roll 5. Upper and lower increase benders 13, 14 and upper and lower decrease benders 15, 16 are respectively permitted to work independently of each other of upper and lower devices, or to work simultaneously, by switching changeover valves 23a, 23b. By the present constitution, the cross sectional shape of a rolled metallic strip is controlled to a good condition. |
