JP2000343111A - Double chock rolling machine - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an inexpensive double-chock rolling mill in which a bearing life due to an unbalanced load is small. SOLUTION: The action lines y1 and y2 of the double-row tapered roller bearing device 1 of the outer chock B1 are crossed on the radial outside of the bearing outer ring 12, and the action point distance Y of the rolling element load is shifted 2X of the work roll A. By setting the length to be longer as described above, even if an eccentric load is applied to the bearing device, a reversal load is not generated, thereby suppressing a reduction in bearing life.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a double-chock rolling mill having a roll bending function.

[0002]

2. Description of the Related Art In order to ensure the flatness of a rolled product, a work roll shift rolling mill provided with a roll bending device is used.
This type of rolling mill has a pair of upper and lower work rolls, and controls the flatness of a rolled plate by changing the roll deflection by sliding the pair of upper and lower work rolls in opposite directions in the roll axis direction. is there. FIG. 2 is a horizontal cross-sectional view showing the configuration of a conventional rolling mill, in which a pair of work rolls A are arranged side by side in a direction perpendicular to the paper surface.
FIG. 2 shows a horizontal cross-sectional view of one of a pair of work rolls A slid so as to be displaced in the axial direction in the upper half, and a horizontal cross-section of the other work roll A in the lower half. It is shown. Therefore, the rolled plate material is supplied with the plate surface parallel to the paper surface, and is stretched in a direction orthogonal to the central axis of the work roll A. As shown in FIG. 2, the configuration of the rolling mill includes a roll housing E, a pair of work rolls A, a choke B that supports the roll necks A0 at both ends of the work roll A, and a choke B and the housing E. And a project block C interposed therebetween to apply a bending load by sliding in the roll shift direction in synchronization with the shift of the work roll A. Further, two types of single chocks and double chocks are used as the chocks B, and the double chocks will be described in detail below.

FIG. 3 is a sectional view of a main part of a bearing portion of a conventional double-chock type rolling mill. Roll neck A0
The outer chock B3 incorporating the double row tapered roller bearing device 3 is fitted to the small diameter roll shaft A1, and the inner choke B2 incorporating the four row tapered roller bearing device 2 is fitted to the large diameter roll shaft A2. . The four-row tapered roller bearing device 2 includes four outer ring raceways 22a opposed to each inner ring raceway 21a concentrically with a pair of inner rings 21 having two rows of conical inner ring raceways 21a having a large diameter at the center. The outer ring 22 is disposed together with the outer ring spacer 25. The inner ring 21 is formed integrally with the entire circumference, and the inner circumference is loosely fitted to the outer circumference of the large-diameter roll shaft A2 for convenience of roll exchange. In addition, each inner raceway 21a
A tapered roller 23 as a rolling element is interposed between the outer raceway 22a and the outer raceway 22a. Similarly, the double-row tapered roller bearing device 3 is fitted to the small-diameter roll shaft A1, and has an inner ring 31 provided with two rows of conical inner ring tracks 31a having a large diameter at the center of the bearing, and faces the inner ring track 31a. Pair of outer races 32 provided with outer raceways 32a to be formed, and a pair of outer races 3
An outer ring spacer 35 interposed between the two and a tapered roller 33 rotatably interposed between each inner ring track 31a and an outer ring track 32a facing the inner ring track 31a.

When the work roll A is shifted in the axial direction, the chock B and the project block C slide through the liner sliding portion D, so that the liner sliding portion D is worn and rattling occurs. Due to this rattling, each of the chocks B and the work rolls A are not perpendicular to the passing direction of the rolled plate material, so that the rolled plate material is drawn or the plate breaks. For this reason, maintenance is required in a relatively short cycle, and there is a problem that the operation rate is reduced. In order to reduce the influence of the wear of the liner sliding portion D, it is necessary to fix the project block C without sliding in synchronization with the shift of the work roll A, and to reduce the number of liner sliding portions D used. It is valid.

However, when the project block C is fixed, when the work roll A is shifted, the load center is shifted with respect to the respective bearing centers of the bearing devices 2 and 3, so that an eccentric load is applied to the bearings. In particular, when the load center comes outside the range of the action point distance indicated by Z and Y in FIG. 3, a reversal load is generated in the bearing, and the life of the bearing is greatly reduced. Therefore, the load center is set to be axially inner than the action point distances Z and Y,
It is necessary to prevent the reversing load from being generated in the bearing devices 2 and 3. Note that the working point distance is set in the bearing devices 2 and 3
Is defined by the distance between two points at which the action line of the rolling element load intersects the center axis of the work roll A. However, when the work roll A is shifted to the right or left in the axial direction by the distance X, the bending load center position is shifted to the distance X (+ X or -X).
Move by X). As a result, when the shift amount 2X is larger than the operating point distance, a reversal load is applied to the bearing devices 2 and 3, and the bearing life is extremely shortened. Therefore, the shift amount 2X is required to be less than or equal to Y and Z in the above-mentioned double chocking method. For this reason, in the case of a double-chock rolling mill having a small value of Y, the allowable shift amount is limited to be very short, and there is a problem that the range in which the shape can be controlled is reduced.

[0006] In order to improve the above problem, the following methods have been proposed. (1) A bending cylinder is built in a chock so that a bending force always acts uniformly in the axial direction of a work roll (Japanese Patent Publication No. 55-25922, Japanese Patent Application Laid-Open No. 59-153504). (2) By fixing the project block, each pressure of a plurality of bending cylinders held in the project block can be adjusted so that the resultant bending force acting on the bearing always acts on the axial center position of the bearing. (Japanese Patent Publication No. 63-55369). However, (1)
Is costly to remodel the chock,
(2) has a problem that it is difficult to apply to a double-chock rolling mill.

[0007] In view of the above-mentioned conventional problems, an object of the present invention is to provide an inexpensive double-chock rolling mill in which the life of a bearing due to an unbalanced load is small.

[0008]

According to the present invention, there is provided a double-chock rolling mill in which both ends of a work roll are supported by an inner chock and an outer chock, and the work roll is shifted in its axial direction. In the double-chock rolling mill that applies a bending load to the work roll via a project block, the outer chock includes an inner ring formed with a pair of conical inner ring tracks having a small diameter at the center of the bearing, and the inner ring. An outer ring formed concentrically with the inner ring raceway and having a conical outer ring raceway opposed to the inner ring raceway and having a small diameter on the center side of the bearing, and a plurality of intermediate rings interposed between the inner ring raceway and the outer raceway facing the same. Double row tapered rollers, and the action line of the rolling element load intersects radially outside of the outer ring. Characterized in that it has a bearing apparatus rollers (claim 1).

According to the double-chock rolling mill having the above configuration, the action line of the double-row tapered roller bearing device is configured to intersect radially outside the bearing outer ring. Can be long enough. For this reason, even if an unbalanced load acts on the bearing device, a reversal load is unlikely to occur, so that a reduction in bearing life is suppressed even when the shift amount is large.

The working point distance of the double-row tapered roller bearing device is preferably equal to or more than the shift amount of the work roll. According to this double-chock rolling mill, a large permissible shift amount can be obtained because the action point distance of the rolling element load is equal to or longer than the work roll shift amount. For this reason, even if the load position of the bending load changes significantly, the reduction in the bearing life is suppressed.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing a main part of a bearing device for a double choke rolling mill according to the present invention. The configuration of the whole rolling mill other than that shown in FIG.
It is the same as the conventional rolling mill shown in FIG. In FIG.
The bearing device of this double-chock rolling mill is for supporting the roll neck A0 of the work roll A, and includes a four-row tapered roller bearing device 2 provided between the roll neck A0 and the inner chock B2. It comprises a double row tapered roller bearing device 1 provided between the neck A0 and the outer chocks B1.

The double-row tapered roller bearing device 1 has an inner ring 11 fitted with a small-diameter roll shaft A1 of a roll neck A0 and provided with a pair of conical inner ring raceways 11a having a small diameter at the center of the bearing. An inner ring spacer 14 provided at a central portion between the inner ring 11 and an inner ring raceway 11
a, an outer race 12 provided with a pair of conical outer raceways 12a facing each other and having a small diameter on the center side of the bearing, an outer race spacer 15 provided at a central portion between the outer races 12, and each inner race race 1
A plurality of tapered rollers 13 are provided between the outer raceway 1a and the outer raceway 12a. An outer chock B <b> 1 is fitted to the outer race 12.

The four-row tapered roller bearing device 2 is fitted to a large-diameter roll shaft A2 of a roll neck A0. This four-row tapered roller bearing device 2 has a conical inner raceway 21a.
Are provided in two rows, and a pair of inner races 21 having a large diameter at a center portion thereof, and an inner race spacer 2 interposed between the pair of inner races 21 are provided.
4 and four outer raceways 22a opposed to the inner raceway 21a.
Outer ring 22 provided with the outer ring, and each outer ring raceway 22a of the outer ring 22
An outer race spacer 25 provided between the outer races 21 and a tapered roller 23 rotatably interposed between the inner raceways 21a and the outer raceway 22a opposed to the inner raceways 21a.

In the four-row tapered roller bearing device 2 and the double-row tapered roller bearing device 1, the inner rings 11, 21 are provided.
Large flanges 1b and 2b are provided at both ends of the outer periphery of the tapered roller with which the large-diameter side end faces of the tapered rollers are in sliding contact. Are provided with small flange portions 1c, 2c with which the small-diameter side end surfaces of the tapered rollers 13, 23 abut. The inner ring raceways 11a and 21a are provided with outer ring spacers 15 and 25, respectively.
Are formed to be separated from each other by a predetermined distance in accordance with the width dimension of.

In the above configuration, the action lines y1, y2 of the rolling element load of the double row tapered roller bearing device 1 determined by the inner raceway 11a and the outer raceway 12a are shown in FIG.
As shown in FIG. Further, in the four-row tapered roller bearing device 2, the action lines z <b> 1 and z <b> 2 of the pair of rolling element loads form an inverted C shape that intersects radially inside the outer ring 22. Similarly, the other pair of action lines z3 and z4 also form an inverted C-shape crossing on the radially inner side of the outer ring 22.

Accordingly, as shown in FIG. 1, the action point distances Y and Z are determined from the action lines y1, y2, z1 to z4 and the work roll center axis A3. That is, the tapered roller 23 on the center side of the bearing of the four-row tapered roller bearing device is used.
Is the distance between two points where the action lines z2 and z3 intersect with the center axis of the work roll, and the action of the rolling element load on the tapered rollers 13 of the double row tapered roller bearing device described above. The point distance Y is a distance between two points where the action lines y1 and y2 intersect with the work roll center axis A3.

With the above arrangement, in the double-chock rolling mill provided with the four-row tapered roller bearing device and the double-row tapered roller bearing device, the action point distance Y of the double-row tapered roller bearing device 1 is represented by an action line y1, y2 can be set large enough to intersect at the radially outer side of the outer ring 12. Therefore, Y> 2X can be easily satisfied. Therefore, in this double-chock rolling mill, the allowable shift amount X is not limited by the working point distance Y of the double-row tapered roller bearing device, but is extended to the working point distance Z of the four-row tapered roller bearing device. The effect of the roll shift can be sufficiently exhibited.

[0018]

As described above, according to the double-chock rolling mill according to the first aspect, it is possible to prevent the occurrence of a reversal load even in the double-row tapered roller bearing device of the outer chock. However, it is possible to suppress a decrease in the bearing life. For this reason, the double row tapered roller bearing device is
Since a large allowable shift amount can be realized without changing to a bearing having a large capacity such as a row tapered roller bearing, it is not necessary to change the structure of the rolling mill and it is inexpensive.

According to the double-chock rolling mill of the second aspect, since the working point distance of the double-row tapered roller bearing device of the outer chock is large and the allowable shift amount is not limited, the bias generated when the project block is fixed is not limited. A reduction in the bearing life is suppressed even with a load. For this reason, abrasion and backlash caused by the liner sliding portion can be eliminated, and the operation can be stabilized and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing one embodiment of a bearing portion of a double choke rolling mill of the present invention.

FIG. 2 is a horizontal cross-sectional view showing a configuration of a conventional double choke rolling mill, in which a pair of work rolls A are arranged side by side in a direction perpendicular to the paper surface. The upper half shows a cross-sectional view of one of the pair of work rolls A slid so as to be displaced in the axial direction, and the lower half shows a cross-section of the other work roll A.

FIG. 3 is a sectional view of a main part of a bearing part of a conventional double-chock rolling mill.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double row tapered roller bearing device 11 Inner ring 11a Inner ring track 12 Outer ring 12a Outer ring track 13 Tapered roller A Work roll B1 Outer chock B2 Inner chock C Project block Y Working point distance X Shift amount

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoji Konno 1-chome, Kawasaki-dori, Mizushima, Kurashiki-shi, Okayama Pref. GA36

Claims (2)

[Claims] 1. A double-chock rolling method in which both ends of a work roll are supported by an inner chock and an outer chock, the work roll is shifted in the axial direction, and a bending load is applied to the work roll via a project block. In the machine, the outer chock has an inner ring formed with a pair of conical inner ring raceways having a small diameter on the center side of the bearing, and a conical ring arranged concentrically with the inner ring and facing the inner ring raceway and having a small diameter on the center side of the bearing. An outer ring on which an outer raceway is formed, and a plurality of tapered rollers interposed between the inner raceway and the outer raceway facing the outer raceway, and the line of action of the rolling element load is the diameter of the outer raceway. A double-chock rolling mill comprising a double-row tapered roller bearing device that crosses outside in the direction. 2. The double-chock rolling mill according to claim 1, wherein a working point distance of the double-row tapered roller bearing device is equal to or longer than a shift amount of the work roll.