The 8-hi rolling mill is a rolling mill for rolling a thin strip, and an intermediate roller is installed between the upper and lower pairs of horizontally arranged back support rolls and the work rolls, so as to avoid the back support roll bearing directly contacting the work roll, which can improve the performance of the strip.
The work roll of the eight-roll mill can be axially tilted, and has the function of positive and negative bending, which enhances the shape adjustment ability of the rolling mill and improves the quality of the strip; the intermediate roll is a drive roll that reduces the work roll diameter and reduces rolling power consumption. The work roll, the intermediate roll, and the backup roll all achieve rapid roll change, which improves the unit operating rate.
From the structure of the frame, the entrance and exit guide frame of 8-hi rolling mill is integrally welded structure, which is respectively installed in the middle of two racks and is positioned by the stop, and the wedge key is locked.
The upper movable guide plate is connected by a pin hinge, and the hydraulic cylinder is used as a power source to swing up and down with the opening degree of the work roll, thereby preventing the cooling water from directly falling onto the rolling piece; the lower movable guide plate is connected by the pin hinge.
When working, the hydraulic cylinder is used as the power source to close the lower work roller, and the lifting roller acts. When the roller is changed, the swinging cylinder lifts the movable guide plate outward to retreat to the outside of the rack window.
1. 8-Hi rolling Mill is driving by support roller, deviation from the work roll bearing roll center installation, so that the reduction of the diameter of the work rolls is not limited by the torque, and is not affected by horizontal bending. Therefore, the work roll diameter can be small, usually half of the four-roll millwork roll diameter, this off-set 8hi roll mill can be meet the requirements of rolling thin steel and rolling difficult-to-deform products like the cluster mill.
2. Compared with the 4-hi rolling mill, the 8-hi rolling mill requires the rolling force only half of the 4-hi rolling mill.
3. The 8-hi rolling mill has a rigid structure of the larger roller system and roll-shaped adjusting device. Which can be rolled out the strip steel with thickness deviation smaller and flat shape straight.
|Rolling Speed(m/s)||500 Strip Mill||650 Strip Mill||750 Strip Mill||850 Strip Mill||1150 Strip Mill||1450 Strip Mill|
|Transmission||Working Roll||Working Roll||Working Roll||Working Roll|
1. The reduction of the work roll diameter is not limited by the torque and is not affected by the horizontal bending. The work roll diameter can be small, generally only the same The diameter of the work roll of the type four-roll mill is about one-half of the diameter of the backup roll, which is only 15%-20% of the diameter of the backup roll, and the rolling force is only half of that of the four-high mill.
2. 8-hi rolling mill can meet the requirements of rolling thin strips and difficult-to-deform metal products like multi-roll mills, and its structure is relatively simple. On the support arm that rotates about the axis of the lateral support roll, the lateral support roll abuts against the large backup roll. This does not consume the torque supplied to the work rolls in frictional contact with the backup rolls, which has a beneficial effect on the work rolls.
3. Like the multi-roll mill, the partial eight-roll mill has a rigid roller structure and a roller-type adjustment device. The mill has a small total bounce value, and the roll shape can be adjusted at any time during the rolling process so that the thickness can be rolled. Small deviation and good shape of the strip.
4. The work roll support is simple to fix, the roll change is relatively simple and convenient, and the roll loss is small. The friction loss between the roll gaps is small, and the rolling mill can be lubricated and cooled by the emulsion to reduce the friction during rolling.