JPH05154518A - Backup roll device for rolling mill - Google Patents

Abstract

PURPOSE:To set rolling load to high by fitting a backup shaft through support rolls having short length barrel part rotatably and slidingly shiftably to the outer periphery of the backup shaft and transmitted to a work roll and sliding keys and applying surface treatment to the outer peripheral surface of the shaft and the inner peripheral surfaces of the support rolls. CONSTITUTION:One pair of the work rolls 21 for executing rolling reduction to a rolling material 23 and one set of backup roll devices 28 transmitted to each work roll are provided and a pressing means for adjusting bearing interval between the work rolls is assembled in a housing. The each backup roll device is formed with the separated support roll 34R, 34L having short length barrel part separated in the roll shaft direction and the backup shaft 32 for supporting slidably in the shaft direction is provided. The backup shaft is supported rotatably with the housing and fitted through the separated support rolls and sliding keys 41, and the surface treatment is applied to the outer peripheral surface of the backup shaft and the inner peripheral surfaces of the separates support rolls. By this method, the rolling load can be set to high.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in the fields of iron and steel industry and non-ferrous industry, and is used in a rolling mill for passing a plate material such as a steel plate between rolls to perform plastic deformation to obtain a desired plate thickness. , Especially for a device for backing up when performing roll bending for shape correction and crown correction.

[0002]

2. Description of the Related Art Generally, various methods have been proposed to control the shape of a material to be rolled. For example, a four-high rolling mill has a pair of work rolls having a relatively small diameter,
They are equipped with backup rolls of relatively large diameter arranged so as to sandwich them from the outside. All of them are formed to have substantially the same cylinder length so as to roll over the entire length, and a bending cylinder is installed between the bearings of the work rolls. I am trying to install it.

The material to be rolled is passed through such a rolling mill to obtain a strip material having a desired plate thickness. As the material to be rolled passes, the central portion of the work roll is expanded and the strip after rolling is rolled. Since the material to be rolled has a so-called middle-height cross-sectional shape in which the central portion is thick and both side edges are thin, a crown is formed on the backup roll and the bending cylinders are acted so that the necks of the work rolls extend in mutually expanding directions. By driving it, the pressure lower surface of the work roll is adjusted to be flat, and shape control is performed to correct the crown generated in the material to be rolled.

[0004]

However, in the above conventional rolling mill, it is difficult to give sufficient roll bending to the work rolls because the work rolls and the intermediate rolls are constrained on the entire surface of the backup rolls. In addition to lacking the absolute ability of shape control, there are drawbacks such as the need to change the crown shape by changing the backup roll depending on the strip width, strength, shape, etc. of the material to be rolled, especially in the 4-high rolling mill. Further, since the backup roll rolling on the work roll and the intermediate roll comes into full contact, the backup fulcrum cannot be arbitrarily changed, and the shape cannot be controlled at an arbitrary position. Moreover, it is necessary to polish the entire surface of the backup roll in terms of maintenance, and there is a drawback that maintenance is difficult and a sufficient space space is required on the side of the rolling mill due to the shift mechanism of the intermediate roll.

As a method for solving such a drawback, the following constitution is adopted. That is, the backup roll device has a backup shaft arranged in parallel with the work roll, which is separated into right and left in the roll axis direction,
A pair of support rolls having a cylinder length shorter than the plate width of the material to be rolled are attached so as to be slidably movable in the axial direction. The pair of support rolls are rolled on the work rolls and serve as backup supports for the work rolls during rolling. Similarly, the lower backup roll device also has a backup shaft and a pair of left and right support rolls attached to the backup shaft. The lower backup roll device serves as a backup support at the time of rolling so as to be rolled and contacted with the lower work roll. ing. Further, the support roll is mounted on the backup shaft via a rotary bearing using rollers or rollers, and thrust bearings are arranged on both end surfaces.

[0006] Such a rolling mill has the advantage that the roll bending effect can be sufficiently exerted without being restricted by the conventional full-contact backup roll, but it is restricted by the manufacturing of the rotary bearing. Therefore, the outer diameter of the backup roll becomes large. It is difficult to disassemble and assemble the rotating bearing that has been fully manufactured. It is difficult to control the clearance between the inner diameter of the rotating bearing and the backup shaft. If the backup shaft thermally expands due to thermal expansion, the support roll may not be able to move horizontally. If the work roll bends during rolling, the backup shaft also bends, which may cause the rotary bearing to seize. Such drawbacks still remain.

[0007]

In order to achieve the above object, a backup roll device for a rolling mill according to the present invention comprises:
It is equipped with a pair of work rolls that roll down the rolled material and a pair of backup rolls that roll into contact with each work roll. Both end bearings of each roll are attached to the housing, and the bearing spacing between the pair of work rolls is adjusted to control the crown. In a rolling mill having the above-mentioned pressurizing means incorporated in the housing, each of the backup rolls is formed by a pair of separation support rolls having a short cylinder width and separated in the roll axial direction, and the separation support rolls are slid in the axial direction. A backup shaft that is movably supported. The backup shaft is rotatably supported by the housing, and is mounted on the outer peripheral surface of the backup shaft or the inner peripheral surface of the separated support roll by mounting it via a separation support roll and a slide key. Make the configuration.

[0008]

According to the above construction, the function of each backup roll that suppresses the work roll bending that directly rolls down the material to be rolled is to provide a pair of support rolls that are rolled and contacted with the work roll and separated in the roll axial direction, and It is demonstrated by the installed backup shaft and supports the work roll rolling force. The pair of separation support rolls are individually movable in the axial direction, and the bending moment fulcrum is changed by the movement of the positions.
The roll bending amount can be adjusted by the bending means provided on the work roll neck. Therefore, the overall amount of bending is controlled by the position movement of the support rolls, the shape of the crown of the material to be rolled, etc. can be controlled, and the bending moment fulcrum can be arbitrarily changed. improves.

In particular, according to the present invention, since the backup shaft has a cylindrical shape, the structure is simple, the cross-sectional performance of the backup shaft can be increased, and the flexure of the shaft can be minimized. Regardless of the position of the support roll, a uniform fixed load is applied to the inner peripheral surface of the support roll, and the sliding bearing makes surface contact with the backup shaft, so there is a risk of seizure even at high rolling loads. Moreover, the rotation torque can be reliably transmitted by the slip key. Therefore, the support roll can be stably held, and thus the bending fulcrum can be reliably set. In addition, since the backup shaft has a large cross-sectional performance, it is possible to give the backup a sufficient supporting force and set a high rolling load.

Here, in order to move the position of the support roll, a guide rod is provided in parallel with the backup shaft, and a bracket-shaped guide member for holding each support roll is attached to the guide rod so as not to interfere with the backup shaft. In advance, these guide members may be moved. The pair of guide members may be simultaneously driven in a direction of moving closer to or away from each other depending on the plate width of the material to be rolled, but they can also be moved independently. As a driving method, a screw rod method, a hydraulic cylinder method, or the like can be adopted as appropriate.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of a backup roll device for a rolling mill according to the present invention will be described in detail below with reference to the drawings.

3 to 4 show the entire structure of a rolling mill equipped with a backup roll device according to the embodiment. In this rolling mill, as shown in the drawing, a pair of upper and lower work rolls 21 and 22 which are parallel to a gate-shaped housing 20 are horizontally mounted so as to be capable of rolling contact with each other. It is possible. A pair of intermediate rolls 24 and 26 that are rolled in parallel with the upper and lower work rolls 21 and 22 so as to sandwich them from above and below are laterally mounted on the housing 20. Intermediate rolls 24 and 26 are work rolls 2
It is formed to have a diameter larger than the diameters of the rolls 1, 22 to transmit the rolling force, but in particular, the barrel length is set to be equal to or greater than the plate width of the material 23 to be rolled, and the barrel lengths of the work rolls 21, 22 are set. It is set to be shorter. Therefore, while the intermediate rolls 24 and 26 are in full contact with the work rolls 21 and 22 in the state of being assembled in the housing 20, the end portions of the work rolls 21 and 22 are, as shown in FIG. It is set so as to protrude from the end of 26 by a predetermined length.

In addition to such a roll row, an upper backup roll device 28 and a lower backup roll device 30 are also laid horizontally in parallel at the upper and lower positions of the intermediate rolls 24 and 26 so as to sandwich them.

The upper backup roll device 28 has a backup shaft 32 arranged in parallel with the intermediate roll 24, which is divided into right and left in the axial direction of the roll and has a body length shorter than the plate width of the material 23 to be rolled. The pair of support rolls 34R and 34L are attached so as to be slidably movable in the axial direction. This pair of support rolls 34R,
The reference numeral 34L rolls on the upper intermediate roll 24 and serves as a backup support for the work roll 21 and the intermediate roll 24 during rolling. Similarly, the lower backup roll device 30 also includes a backup shaft 36 and a pair of left and right support rolls 38R, 3 attached to the backup shaft 36.
8L, and these are rolled and contacted by the lower intermediate roll 26 to provide backup support during rolling.

Further, the support rolls 34R, 34R
L, 38R, and 38L are, as representatively shown for the upper backup roll device 28 in FIG. 1, inserted into the backup shaft 32, and then slide keys are arranged on the backup shafts 32 and 36. Bearings 42 and 44 are provided. Outer peripheral surface of backup shaft 32 and support rolls 34R, 3
In order to improve surface hardness, wear resistance, heat resistance, lubricity, etc. on the inner surface of 4 L, the desired one of nitriding treatment, carburizing treatment, vapor deposition treatment of ceramics, etc., and chemical densification treatment Various types of surface treatments can be performed. Outer diameter of backup shaft 32 and support rolls 34R, 3
The gap between the inner diameters of 4L is such that the support rolls 34R and 34L can move horizontally even if the backup shaft 32 thermally expands. As described above, the surface treatment is not limited to both the outer peripheral surface of the backup shaft 32 and the inner peripheral surfaces of the support rolls 34R and 34L.
The surface treatment may be performed on either the outer peripheral surface of or the inner peripheral surfaces of the support rolls 34R and 34L. The slide key 41 is attached to a key groove 41a formed in the axial direction of the backup shafts 32, 36, and the inner peripheral surfaces of the support rolls 34R, 34L, 38R, 38L (not shown) are formed slightly larger than the slide key 41. The slide key 41 and the backup shafts 32 and 36 are slidably arranged in the axial direction.

The neck portions of the upper and lower work rolls 21 and 22 and the intermediate rolls 24 and 26, and the backup shaft 3 of the upper and lower backup roll devices 28 and 30 described above.
As shown in FIG. 4, bearings 4 and
6, 47, 48, 49, 50, 52 are attached, and these are attached to the housing 20 in a tandem arrangement. A lowering cylinder 54 is provided at a lower position of the housing 20, and a predetermined rolling pressure is generated between the work rolls 21 and 22 by driving this.

The specific construction of the backup roll devices 28 and 30 according to the present embodiment in such a rolling mill will be described with reference to FIGS. FIG. 1 shows an upper backup roll device 28, and each of the separation support rolls 34R, 34L of this device 28 can be adjusted in position by slidingly moving in the roll axial direction. For this position movement, the support rolls 34R, 3
4L has roll guides 56R and 56L as driving members.
Are engaged.

As shown in FIG. 2, two parallel guide shafts 58, which are bridged between the bearings 50 at both ends of the backup shaft 32, are formed by the backup shaft 32.
It is installed in parallel with. By attaching the backup shaft 32 and the guide shaft 58 to the common bearing 50, the parallelism between the shafts 32 and 58 is maintained. The roll guides 56R and 56L are attached to the guide shaft 58. The roll guides 56R and 56L penetrate the guide shaft 58 and support rolls 34R and 34L.
Slide casing 6 formed so as not to interfere with L
It is equipped with 0R and 60L. The slide casings 60R and 60L are extended toward both end surfaces of the support rolls 34R and 34L, and the support rolls 34R and 34L are extended.
Thrust bearing 4 with L attached to both end faces
Thrust bearing support 62 for sandwiching 2,44,
64 is attached. As shown in FIG. 2, each of the supports 62 and 64 is formed in a donut shape so as not to interfere with the backup shaft 32, and the slide casings 60R and 60L move to press the end surfaces of the support rolls 34R and 34L. Therefore, the support rolls 34R and 34L can be moved in the axial direction.
Such a configuration is similar in the lower backup roll device 30.

Here, the support rolls 34R and 34R
Driving means for properly moving the positions of L, 38R, and 38L is provided for each of the backup roll devices 28 and 30. This corresponds to a pair of separation support rolls 34R, 34L (3
8R, 38L), the intermediate roll 24 (2
6) to approach or separate in the axial direction along the outer peripheral surface. The upper backup roll device 28 will be described as a representative. As shown in FIG. 2, a pair of screw rods 70R, which are rotatably supported by the bearings 50 at both ends, are located at intermediate portions of the pair of guide shafts 58.
70L, which has left and right roll guides 56R, 56
The slide casings 60R and 60L of L are threadedly penetrated. In this embodiment, one screw rod 70R is attached to the right slide casing 60R.
It is possible to individually move the screw rod 70L in the axial direction by screwing the other screw rod 70L into the left slide casing 60L.
Drive motors 72R and 72L for rotationally driving the screw rods 70R and 70L are attached to one bearing 50 of the backup shaft 32 so as to give a predetermined rotation to the screw rods 70R and 70L.

Of course, one screw rod structure may be used, and the screw may be formed into a reverse screw with the central portion sandwiched therebetween, so that the coaxial support rolls 38R and 38L are simultaneously moved toward or away from each other. In this case, the screw fitting portions of the slide casings 60R and 60L also have a reverse female screw structure adapted to the screw of the screw rod. Therefore, when the screw rod is rotated, the roll guides 56R and 56L screwed to the screw rod are moved toward or away from each other. In this way, the pair of support rolls 34R and 34L are slidably movable along the backup shaft 32.

The above-described configuration is similarly configured in the lower backup roll device 30.

A work roll bending device 110 and an intermediate roll bending device 120 are incorporated in the rolling mill housing 20. The work roll bending device 110 includes an upper roll bending rod 11
2. It has a lower roll bending rod 114, which can be brought into and out of contact with the upper work roll bearing 46 and the lower work roll bearing 47 so that the bending action is performed by hydraulic pressure. The intermediate roll bending device 120 includes the upper roll bending rod 12
2. It has a lower roll bending rod 124, which can be brought into contact with the intermediate roll bearings 48 and 49, respectively, to independently perform the bending action.

In FIG. 4, reference numeral 54 is a pressure reducing cylinder for raising the head 130. The operation of the head 130 pushes up the backup shaft bearing 52 of the lower backup roll device 30, and this rolling force is applied to the lower support rolls 38R, 38L and the lower intermediate roll 2.
6, lower work roll 22, upper work roll 21, upper intermediate roll 24, upper support rolls 34R, 34
L, upper backup shaft bearing 50, housing 2
It is transmitted to zero to generate the desired rolling force.

The operation of the backup roll device of the rolling mill configured as described above is as follows.

Before rolling, the positions of the support rolls 34R, 34L and 38R, 38L are determined in advance according to the width of the material 23 to be rolled. In this case, the support rolls 34, 3
The rolling contact position of the No. 8 to the work rolls 21 and 22 is the rolled material 2
It is set at a position where it overlaps with the side part of 3. This initial setting uses roll bending rods 102 and 202 and a roll balancing cylinder (not shown),
The work rolls 21, 22, the intermediate rolls 24, 26 and the support rolls 34, 38 are lightly contacted with each other. Then, after that, the position adjusting motor 72 of the support rolls 34 and 38 is driven and moved to a preset position. Thereby, the pair of support rolls 34R, 34L,
And the intervals of 38R and 38L are set to desired intervals.

After the initial setting is completed, the rolled material 23 is passed between the work rolls 21 and 22. As a result, the material to be rolled 23 is rolled to a desired plate thickness and emerges as a strip material. This shape determination is performed visually or by a contact method using a sensor roll or a non-contact method using light or magnetism. When the ear extension or the middle extension occurs due to this determination, the drive motor 72 is operated to move the pair of support rolls 34R, 34L and 38R, 38L so as to move toward or away from each other, and By adjusting the amount of bending moment acting on the work rolls 21 and 22 through the rolls 24 and 26, it is possible to suppress the occurrence of abnormal shape and obtain a rectangular strip material. At this time, by adjusting the bending force by the intermediate roll bending device 120, the intermediate rolls 24, 2 can be adjusted.
Since the bending amount of 6 is controlled, a large shape correction function can be exerted by the interaction with the position movement amount of the support rolls 34R, 34L and 38R, 38L. That is, the correction area can be adjusted by moving the positions of the support rolls 34R, 34L and 38R, 38L, and the correction amount can be adjusted by the intermediate roll bending device 120.

When the rolled material 23 has an edge drop, the work roll bending device 11
The bending force of the work rolls 21 and 22 by 0 is controlled. The work rolls 21 and 22 are intermediate rolls 24 and 2.
Since both ends project from 6, the bending device 11
0 by supplying pressure oil to the rods 112, 114
Of the intermediate rolls 24 and 26 is largely bent mainly at the protruding portions from the edges of the intermediate rolls 24 and 26, and acts to control the edge drop. Of course work rolls 21 and 22
Since it has rigidity, the bending force is transmitted to the intermediate rolls 24 and 26.

According to the rolling mill provided with the backup roll devices 28 and 30 of such an embodiment, the work roll 2
Since the bending fulcrums of the rolls 1, 22 or the intermediate rolls 24, 26 can be freely changed, the roll bending effect can be sufficiently exerted without being restricted by the conventional full-contact backup roll. Further, since the positions of the upper and lower support rolls 34R, 34L and 38R, 38L can be individually changed, the shape can be controlled at any position in the plate width direction. Therefore, in addition to shape defects such as medium elongation and edge elongation of the material to be rolled, it is possible to obtain an advantage that it is possible to control not only shape defects of composite elongation that is a composite of the two.

In the above embodiment, the intermediate rolls 24, 2
An example applied to a 6-high rolling mill equipped with No. 6 is shown in FIG.
It can be applied to the backup roll of the four-high rolling mill shown in (1), and the work roll 21,
It can also be applied to those in which the diameter of 22 is larger than that of the intermediate rolls 24 and 26. It can also be applied to a backup roll of a cluster rolling mill as shown in Fig. 3 (3). of course,
Although not shown, it goes without saying that the present invention can be applied to any rolling mill having other special structure, such as a rolling mill having the backup roll device of the embodiment only on the upper portion. Further, although the pair of support rolls 34R, 34L or 38R, 38L is applied in the above embodiment, it can be applied to a rolling mill having a plurality of support rolls 34, 38 such as three and four. Is.

[0030]

As described above, the backup roll device for a rolling mill according to the present invention comprises a pair of work rolls for rolling down the rolled material and a pair of backup rolls for rolling contact with each work roll. In the rolling mill in which the bearings at both ends of the backup roll are installed in the housing, and the pressurizing means for adjusting the bearing spacing between the pair of work rolls and crown control is incorporated in the housing, the backup rolls are separated in the roll axial direction. A backup shaft that is formed by a pair of separation support rolls having a short body width and that supports the separation support rolls so as to be slidable in the axial direction. The backup shaft is rotatably supported by the housing and slides with the separation support rolls. Install it via the key and attach it to the outer peripheral surface of the backup shaft or separate Since the bearing is not interposed between the backup shaft and the support roll by adopting a structure in which the inner surface of the heat roll is subjected to surface treatment, there is no restriction in manufacturing the bearing as in the past, and the backup shaft and the support roll are not restricted. The clearance between the back-up shaft and the back-up shaft does not affect the horizontal movement of the support roll even if the backup shaft thermally expands. Further, since the outer peripheral surface of the backup shaft and the inner peripheral surface of the support roll are in surface contact with each other, the rolling load can be set high.

[Brief description of drawings]

FIG. 1 is a sectional front view of a main part of a backup shaft device for a rolling mill according to a first embodiment.

FIG. 2 is a cross-sectional view of FIG.

FIG. 3 is a front view of a rolling mill including the backup roll device of the embodiment.

FIG. 4 is a side view of FIG.

FIG. 5 is an example of another rolling mill in which the embodiment backup roll device can be mounted.

[Explanation of symbols]

 20 Housing 21,22 Work roll 24,26 Intermediate roll 23 Rolled material 28,30 Backup roll device 32,36 Backup shaft 34R, 34L, 38R, 38L Support roll 41 Sliding key 42,44 Thrust bearing 46,47,48, 49, 50, 52 Bearing 54 Rolling down cylinder 56R, 56L Roll guide 58 Guide shaft 60R, 60L Slide casing 70R, 70L Screw rod 72R, 72L Drive motor 110 Work roll bending device 120 Intermediate roll bending device

Claims (1)

[Claims] 1. A pair of work rolls for rolling down a rolled material, and a pair of backup rolls rollingly contacting each work roll. Both end bearings of each roll are attached to a housing, and a bearing gap between the pair of work rolls is provided. In a rolling mill in which pressurizing means for adjusting the crown and for controlling the crown is incorporated in the housing, the backup rolls are formed by a pair of split support rolls having a short cylinder width and separated in the axial direction of the rolls. A backup shaft that supports a roll slidably in the axial direction, the backup shaft is rotatably supported by the housing, and is mounted via a separation support roll and a slide key, and an outer peripheral surface of the backup shaft or an inner peripheral surface of the separation support roll. Rolling characterized by having a surface-treated surface Machine backup roll device.