| 摘要 |
PURPOSE:To make a rolling mill provided with rolls of different diameter suitable for rolling a hardly processable material, and possible to obtain a large rolling reduction, by replacing a work roll of a four-high rolling mill with a small diameter work roll of a cluster type correspondingly to the purpose of use, and by driving both of upper and lower rolls of different diameter. CONSTITUTION:In case of rolling a material S to be rolled by a small-diameter upper work roll 2 and a lower work roll 6 of a cluster roll R, a middle backup roll 5 and the roll 6 of the cluster roll R are respectively driven to rotate through driving shafts 14, 13. Hereupon, the roll 6 is made to a directly driven roll, and the roll 2 is made to a indirectly driven roll receiving the power through the friction between the roll 2 and the roll 5; since two rolls 2, 6 are thus driven at the same time, a rolling reduction about four times of that of a nondriving system can be obtained. The roll 2 is backed up by plural backup rolls 4, 4 on purpose to prevent the decline of the transverse rigidity. If the dimensional margin is admittable, it is possible to drive the roll 2 and the intermediate rolls 3, 3. |
