KR20010042729A - Roll stand with axially displaceable rolls - Google Patents

Abstract

The present invention relates to a roll stand for hot or cold rolling a rolled strip of materials, comprising work rolls, support rolls and optionally intermediate rolls arranged in pairs. At least one pair of rolls 6 is movable in both axial directions and has a shape suitable for correcting the rolling defect. Each movable roll 6 has a hydrodynamic oil film bearing 3 so that the axial movement by the hydraulic device 17 takes place in the hydrodynamic oil film bearing, so that the axis is moved by the movable choke. The disadvantage of rolls moving in the direction is avoided.

Description

ROLL STAND WITH AXIALLY DISPLACEABLE ROLLS}

EP-B 0 091 540 discloses a general roll stand designed as a four or six stage roll stand. Even in the case of a four-stage roll stand, the support rolls are movable in the axial direction with respect to each other beside the work roll, and the movement of the support rolls occurs together with or independently of the work roll. In the case of a six-stage roll stand, the work roll is supported by an intermediate roll positioned on the support roll, and the work roll and / or support roll and / or the intermediate roll are movable relative to each other in the axial direction, and at least two pairs of rolls. Given these curved shapes formed over their entire surface and consisting of convex and concave regions, these groups of curved shapes help the rolls support each other organically at any relative axial position where the rolls are complementary.

The rolls are housed in sliding bearings interposed in the mount. The mount has sliding surfaces, one of which slides on the other or slides on the cross beam of the roll stand and slides axially by thrust rods. Such a structure is very expensive to manufacture.

The present invention relates to a roll stand for hot or cold rolling a rolled strip of materials having work rolls, support rolls, and optionally intermediate rolls arranged in pairs, wherein at least one pair of rolls moves in both axial directions It is possible and has a shape suitable to compensate for rolling defects.

1 is a cross-sectional view of a preferred embodiment of the present invention.

The object of the present invention is to simplify the axial movement of the roll of the roll stand by means of a movable mount.

This object is achieved in connection with the feature of claim 1, wherein the movable roll is positioned over the hydrodynamic oil film bearing, such that axial movement by the hydraulic device is effected in the hydrodynamic oil film bearing. Since the roll moves on the hydrodynamic oil film bearing on its surface, unlike the roll on the sliding surface of the mount, the friction in the axial direction is small. Thus, the roll can be positioned axially without problems or transitions with minimal force. The integrally formed hydraulic device is made smaller in size compared to conventional thrust rods and becomes a roll supporting component.

A small support friction enables axial adjustment even under load. Due to the small space requirements, hydraulics can be applied to all types of rolls (working rolls, supporting rolls, intermediate rolls).

In the case of hot rolling, the support roll is ground to the nth cross section. In the front stand of the hot strip mill the support roll is moved to compensate for the thermal crown of the work roll, especially in the case of infinite rolls. Thus, in the case of CVC work rolls, advance adjustment is required.

The movement of the work roll in the rear stand is operated to limit the grinding and heat crown. Adjustment of the pass-shaped surface of the roll occurs with the bending of the roll. The movement of the support roll in the rear stand increases the range of adjustment of the erroneous passage-shaped surface and is particularly effective in the case of narrow and soft strips as well as in wide and rigid strips.

In the case of cold rolling, the support roll is ground to the CVC-section for correcting the x2-deviation so that the plane deviation is eliminated. In a six-stage device, the working roll or intermediate roll has a CVC cross section for correcting the xn-deviation. In the six-stage device, the support roll has a CVC cross section as a preventive measure to compensate for the work roll "edge drop" phenomenon to compensate for x2-deviation and the middle roll to compensate for xn-deviation. .

The hydraulic device has a ring cylinder fixed to the roll stand, and a smooth hydrodynamic oil film bearing is formed in the hydraulic device in such a way that the annular piston attached to the roll is sealed and moved by the integral ring. Their diameter is larger than the diameter of the bush of the fluid dynamic oil bearing.

The ring of the annular piston is capable of moving the roll in both directions as a type capable of applying pressure on both sides. The two hydraulic packings of the ring cylinders allow the flow of hydraulic oil to be varied and selectively supplied in both operating directions to the annular piston.

In order to detect the axial position of the roll moving in the axial direction, a position indicator is used. This position is controlled by the hydraulic device on the roll stand's automatic control loop using signals from the position indicator.

An advantage of the present invention is that the hydraulic device can be configured together with the fluid dynamic oil film bearing. Therefore, the same mount can be additionally mounted to existing equipment. At this time, the fluid dynamic oil film bearings only need to be replaced. The installation space for the sliding mechanism can be omitted from the roll stand.

Further advantages of the invention are apparent from the accompanying description and the drawings, in which detailed embodiments of the invention are described with reference to the drawings.

The lower right part of the figure shows a longitudinal section of the hydraulic system and the fluid dynamic oil bearing. The roll stand 1 (eg mount) shows the bush 2 of the hydrodynamic oil film bearing 3. The tab socket 4 attached thereto is mounted on the roll pin 5 of the roll 6 together with the conical key.

A ring cylinder 7 is attached to the roll stand 1 and is hermetically conveyed by the annular piston 8. It is engaged with the roll pin 5 on the conical bearing 9. The annular piston 8 represents the range of the ring 10, and the groove 11 of the ring cylinder 7 is movable in the axial direction together with the annular piston 8.

The groove 11 together with the annular piston 8 forms an annular space 12 and is separated by a ring 10. The parts of the annular space 12 are connected to the control hydraulic pressure of the roll stand on the separate hydraulic packing 13.

The free end of the roll pin 5 is sealed by the cover 14. The position indicator 15 is mounted thereon and is engaged with the free end of the roll pin 5 on the tie bar 16. The ring cylinder 7, the annular piston 8 and the position indicator 15 constitute the hydraulic device 17.

The arrangement of the device according to the invention works as follows. The required axial movement of the roll 6 can be moved in the desired adjustment direction by adjusting the hydraulic packing with oil located on the right or left side. This is effective in the piston region of the ring 10, thereby exerting an axial force, which moves the roll pin 5 of the roll 6 with little frictional force by the conical bearing 9. The axial movement of the roll pin 5 is moved over the position indicator 15 by tie bars 16, and the circulation of pressurized hydraulic oil continues until the required roll position is reached.

The arrangement of the device according to the invention is simple and stable and requires an axial feed device with minimal required space, which makes it possible to cover and require no maintenance. Due to this property, installation of the existing roll stand into the mounting stand is also possible.

Claims (8)

At least one pair of rolls of rolls 6 is movable in both axial directions, for hot or cold rolling a rolled strip made of different materials with work rolls, support rolls and optionally intermediate rolls arranged in pairs. And the roll stand having a shape suitable for correcting the rolling defect, each movable roll 6 has a hydrodynamic oil film bearing 3, so that the hydraulic device 17 in the hydrodynamic oil film bearing 17 Roll stand characterized in that the axial movement by). 2. A hydraulic cylinder (17) according to claim 1, characterized in that there is a ring cylinder (7) fixed to the roll stand, and the annular piston (8) attached to the roll is closed and moved by the integral ring (10). Roll stand. 3. Roll stand according to claim 2, characterized in that the ring (10) of the ring piston (8) is pressurized in both directions. The roll stand according to claim 2 or 3, wherein two hydraulic packings (13) are provided in the ring cylinder (7). The roll stand according to any of the preceding claims, characterized in that a position indicator (15) is provided on each movable roll (6). 6. Roll stand according to claim 5, characterized in that the axial position of the movable roll (6) is controllable by the hydraulic device (17) on the automatic control loop of the roll stand using the signal of the position indicator (15). . 7. Roll stand according to any one of the preceding claims, characterized in that the hydrodynamic oil film bearing (3) can be used together with the hydraulic device (17). 8. The hydraulic dynamic oil film bearing 3 can be used in the front and / or rear stand of the hot rolling mill and / or cold rolling mill together with the hydraulic device 17. Roll stand, characterized in that.