A rolling device has an upper and a lower work roll and at least one upper and one lower backup roll. The work rolls and the backup rolls are supported on a common rolling mill stand. The work rolls can be adjusted relative to each other in order to adjust a specified rolling gap. Each of the work rolls is operatively connected to at least one bending device. At least one first bending device is paired with die upper work roll, and at least one second bending device is paired with the lower work roll. The second bending device comprises bending cylinders which are arranged in a vertically fixed manner. The upper work roll can be readjusted or carried by the first bending device, thereby vertically adjusting die height of the rolling gap. The first bending device comprises bending arms that interact with bending cylinders arranged in a stationary manner.

The present invention discloses a rolling-bulging forming hydraulic machine for tubular products, which includes a frame. The frame is provided with an upper rolling mechanism, a lower rolling mechanism, a fixed liquid bulging hydraulic cylinder and a movable liquid bulging hydraulic cylinder. The upper rolling mechanism and the lower rolling mechanism are arranged oppositely, and the upper rolling mechanism and the lower rolling mechanism are used to roll surfaces of a to-be-machined tubular product. The fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder are arranged oppositely, and the fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder are used to perform hydraulic bulging on the to-be-machined tubular product.

The present invention discloses a rolling-bulging forming hydraulic machine for tubular products, which includes a frame. The frame is provided with an upper rolling mechanism, a lower rolling mechanism, a fixed liquid bulging hydraulic cylinder and a movable liquid bulging hydraulic cylinder. The upper rolling mechanism and the lower rolling mechanism are arranged oppositely, and the upper rolling mechanism and the lower rolling mechanism are used to roll surfaces of a to-be-machined tubular product. The fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder are arranged oppositely, and the fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder are used to perform hydraulic bulging on the to-be-machined tubular product.

[Problem] In a small-size rolling mill or a roll press machine, to provide a hydraulic screw-down device compatible with the plate thickness accuracy without using a hydraulic control servo valve.

[Means for Solution]A hydraulic screw-down device that is comprised of a screw to move a piston arranged in a booster cylinder back and forth, and a motor that gives rotational force to the screw controlling freely the rotational angle of the screw so as to move the piston to the purpose position. A screw-down cylinder connected with the booster cylinder through piping makes a ram in the screw-down cylinder move vertically by the move of oil caused by the movement of the piston in the booster cylinder and thereby enables push-up and push-down of the mill roll.

[Problem] In a small-size rolling mill or a roll press machine, to provide a hydraulic screw-down device compatible with the plate thickness accuracy without using a hydraulic control servo valve.

[Means for Solution]A hydraulic screw-down device that is comprised of a screw to move a piston arranged in a booster cylinder back and forth, and a motor that gives rotational force to the screw controlling freely the rotational angle of the screw so as to move the piston to the purpose position. A screw-down cylinder connected with the booster cylinder through piping makes a ram in the screw-down cylinder move vertically by the move of oil caused by the movement of the piston in the booster cylinder and thereby enables push-up and push-down of the mill roll.

The invention relates to a roller device (50) having a stand and two roller sets having at least two rollers (52, 53, 54, 55) disposed in a stand (51) of the roller device, wherein a roll material (56) can be fed between two rollers (53, 54) of the two roller sets for rolling, wherein at least the rollers (52, 53) of a roller set can be displaced in the rolling direction relative to the stand (51), wherein adjustment means are provided between a roller bearing for receiving the rollers and the stand, each on both sides of the roller bearing. It is thereby particularly advantageous if the circumferential speeds of the rollers, such as the working rollers, are different.

There are provided a work-side position measurement device and a drive-side position measurement device for directly measuring positions of roll chocks in a rolling direction, and positions of upper and lower working rolls and upper and lower backup rolls in the rolling direction are adjusted to zero point or predetermined positions. Alternatively, a change caused in the strip wedge due to a minute crossing of the axes of working rolls and backup rolls is calculated, and the quantities of leveling of a work-side rolling reduction cylinder device and a drive-side rolling reduction cylinder device are adjusted to make the strip edge equal to or smaller than a predetermined value. Accordingly, the bilateral asymmetry (strip wedge) of the thickness distribution of a rolled material is easily adjusted even in the event that the positions of the roll chocks in the rolling direction are changed due to wear on various components.

A rolling mill for rolling metal products, comprising two roller stands with a stand cross-member. A roller is rotatably mounted in the roller stands. The roller is operatively connected to a balancing cross-member, and at least one hydraulic piston-cylinder system is arranged in the stand cross-member, with which a tensile force can be generated between the stand cross-member and the balancing cross-member by the hydraulic piston-cylinder system. In order to prevent leakages in particular in the event of tall mill ascending paths, the piston-cylinder system has a cylinder housing with an upper axial end and a lower axial end. A piston is movably arranged in the cylinder housing, and the piston protrudes beyond the cylinder housing both at the upper axial end as well as at the lower axial end in each operating state.

A rolling mill for rolling metal products, comprising two roller stands with a stand cross-member. A roller is rotatably mounted in the roller stands. The roller is operatively connected to a balancing cross-member, and at least one hydraulic piston-cylinder system is arranged in the stand cross-member, with which a tensile force can be generated between the stand cross-member and the balancing cross-member by the hydraulic piston-cylinder system. In order to prevent leakages in particular in the event of tall mill ascending paths, the piston-cylinder system has a cylinder housing with an upper axial end and a lower axial end. A piston is movably arranged in the cylinder housing, and the piston protrudes beyond the cylinder housing both at the upper axial end as well as at the lower axial end in each operating state.

There are provided a work-side position measurement device and a drive-side position measurement device for directly measuring positions of roll chocks in a rolling direction, and positions of upper and lower working rolls and upper and lower backup rolls in the rolling direction are adjusted to zero point or predetermined positions. Alternatively, a change caused in the strip wedge due to a minute crossing of the axes of working rolls and backup rolls is calculated, and the quantities of leveling of a work-side rolling reduction cylinder device and a drive-side rolling reduction cylinder device are adjusted to make the strip edge equal to or smaller than a predetermined value. Accordingly, the bilateral asymmetry (strip wedge) of the thickness distribution of a rolled material is easily adjusted even in the event that the positions of the roll chocks in the rolling direction are changed due to wear on various components.