JP3690640B2 - Double chock rolling machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a double chock rolling mill having a roll bending function.
[0002]
[Prior art and problems to be solved by the invention]
In order to ensure the flatness of the rolled product, a work roll shift rolling mill equipped with a roll bending apparatus is used. This type of rolling mill has a pair of upper and lower work rolls, and controls the flatness of the rolled sheet by sliding the pair of upper and lower work rolls in opposite directions in the roll axis direction to change the roll deflection. 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. In addition, FIG. 2 shows the horizontal cross section regarding one side of a pair of work roll A slid so that it might mutually shift | deviate to an axial direction in the upper half part, and shows the horizontal cross section regarding the other work roll A in a lower half part. It is shown. Therefore, the rolled plate material is supplied with the plate surface parallel to the paper surface and is expanded in a direction perpendicular to the central axis of the work roll A.
As shown in FIG. 2, the rolling mill includes a roll housing E, a pair of work rolls A, a chock B that pivotally supports a roll neck A0 at both ends of the work roll A, a chock B, and a housing E. The project block C is interposed between them and slides in the roll shift direction in synchronization with the shift of the work roll A to apply a bending load. The chock B uses two types, a single chock and a double chock. The double chock will be described in detail below.
[0003]
FIG. 3 shows a cross-sectional view of a main part of a bearing portion of a conventional double chock type rolling mill. The outer chock B3 incorporating the double row tapered roller bearing device 3 is fitted to the small diameter roll shaft A1 of the roll neck A0, and the inner chock B2 incorporating the four row tapered roller bearing device 2 is fitted to the large diameter roll shaft A2. Has been.
The four-row tapered roller bearing device 2 has four outer ring raceways 22a concentric with a pair of inner rings 21 having two rows of conical inner ring raceways 21a having a large diameter at the center side and facing the inner ring raceways 21a. The outer ring 22 having the outer ring is disposed together with the outer ring spacer 25. The inner ring 21 is integrally formed on 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 replacement. Further, a tapered roller 23 as a rolling element is interposed between each inner ring raceway 21a and the opposed outer ring raceway 22a.
Similarly, the double-row tapered roller bearing device 3 is fitted to the small-diameter roll shaft A1 and is opposed to the inner ring 31 provided with two rows of conical inner ring raceways 31a having a large diameter at the bearing center side, and the inner ring raceway 31a. Between the pair of outer rings 32 provided with the outer ring raceway 32a, the outer ring spacer 35 interposed between the pair of outer rings 32, and the outer ring raceway 32a facing each inner ring raceway 31a. A tapered roller 33 is provided.
[0004]
By the way, 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 the rattling, the chocks B and the work rolls A are not perpendicular to the sheet passing direction of the rolled plate material, so that the rolled plate material is squeezed 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 lowered. In order to reduce the influence of the wear of the liner sliding portion D, the project block C is fixed without being slid in synchronization with the shift of the work roll A to reduce the number of use of the liner sliding portion D. It is valid.
[0005]
However, when the project block C is fixed, when the work roll A is shifted, the load center is shifted with respect to the bearing center of each of the bearing devices 2 and 3, so that an eccentric load is applied to the bearing. When the load center is located outside the range of the operating point distance indicated by Z and Y in FIG. 3, a reverse load is generated in the bearing, and the bearing life is greatly reduced. Therefore, it is necessary to prevent the reverse load from being generated in the bearing devices 2 and 3 so that the load center is located inward of the action point distances Z and Y in the axial direction. The action point distance is defined as the distance between two points where the action line of the rolling element load of the bearing devices 2 and 3 intersects the central 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 moves by the distance X (+ X or −X). As a result, when the shift amount 2X becomes larger than the operating point distance, a reverse load is applied to the bearing devices 2 and 3, and the bearing life is extremely shortened.
Therefore, in the double chock method, the shift amount 2X is required to be Y or Z or less. For this reason, in the case of a double-chock rolling mill with a small Y value, the allowable shift amount is limited to be very short, and there is a problem that the range in which shape control is possible is reduced.
[0006]
In order to improve the above problems, the following methods have been proposed.
(1) A bending cylinder is built in the chock so that the bending force always acts uniformly in the axial direction of the work roll (Japanese Patent Publication Nos. 55-25922 and 59-153504).
(2) By fixing the project block, each pressure of multiple 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, since (1) modifies the chock, remodeling costs are required, and (2) has a problem that it is difficult to apply to a double chock rolling mill.
[0007]
In view of the above-described conventional problems, an object of the present invention is to provide an inexpensive double-chock rolling mill that is less likely to reduce the bearing life due to an uneven load.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the double chock rolling mill of the present invention supports both ends of a work roll by an inner chock and an outer chock, shifts the work roll in the axial direction, and passes the project block through the project block. In the double chock rolling mill that applies a bending load to the work roll, the outer chock is arranged concentrically with the inner ring formed with a pair of conical inner ring raceways having a small diameter at the bearing center side, and the inner ring raceway. double the facing and the bearing center side and outer ring is conical ring raceway whose diameter is formed, Ru with a plurality of tapered rollers and interposed respectively between the outer ring raceway opposed thereto and the inner ring raceway in together we have a row tapered roller bearing apparatus, the outer the line of action of the rolling element load of the double-row tapered roller bearing device By crossing the outer side in the radial direction, the working point distance is expanded so as to be more than the working point distance of the work roll and the working point distance of the four-row tapered roller bearing device provided in the inner chock. characterized in that there (claim 1).
[0009]
According to the double chock rolling mill having the above-described configuration, the action line of the double row tapered roller bearing device is configured to intersect on the radially outer side of the bearing outer ring, so that the action point distance of the rolling element load is sufficiently long. can do. For this reason, even if an offset load is applied to the bearing device, a reversal load is unlikely to occur. Therefore, even if the shift amount is large, a decrease in bearing life is suppressed.
[0010]
Further, according to the double chock rolling mill of the above configuration, the distance from the application point of the double row tapered roller bearing apparatus, the point of the four-row tapered roller bearing apparatus provided at the shift amount or more and the inner chocks of the work rolls Since it is enlarged so as to be more than the distance , a large allowable shift amount can be obtained even though the double row tapered roller bearing device is adopted for the outer chock . For this reason, even if the load position of the bending load changes greatly, a decrease in bearing life is suppressed.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of an essential part showing a bearing device of a double chock rolling mill according to the present invention. The overall configuration of the rolling mill other than that shown in FIG. 1 is the same as that of the conventional rolling mill shown in FIG.
In FIG. 1, the bearing device of this double chock rolling mill is for supporting the roll neck A0 of the work roll A, and is a four-row tapered roller bearing device provided between the roll neck A0 and the inner chock B2. 2 and a double row tapered roller bearing device 1 provided between the roll neck A0 and the outer chock B1.
[0012]
The double row tapered roller bearing device 1 is fitted between a small diameter roll shaft A1 of a roll neck A0 and an inner ring 11 provided with a pair of tapered inner ring raceways 11a having a small diameter at the center of the bearing. An inner ring spacer 14 provided in the central portion, an outer ring 12 disposed concentrically with the inner ring 11, opposed to the inner ring raceway 11a, and provided with a pair of conical outer ring raceways 12a having a small diameter at the center of the bearing; An outer ring spacer 15 provided in the center between the outer rings 12 and a plurality of tapered rollers 13 interposed between the inner ring raceways 11a and the outer ring raceways 12a facing each other are provided. The outer ring 12 is fitted with an outer chock B1.
[0013]
The four-row tapered roller bearing device 2 is fitted to the large-diameter roll shaft A2 of the roll neck A0. The four-row tapered roller bearing device 2 includes two rows of conical inner ring raceways 21 a, a pair of inner rings 21 having a large diameter at the center, and an inner ring spacer 24 interposed between the pair of inner rings 21. The outer ring 22 provided with four outer ring raceways 22a facing the inner ring raceway 21a, the outer ring spacer 25 provided between the outer ring raceways 22a of the outer ring 22, and the outer ring raceway 22a facing each inner ring raceway 21a. And a tapered roller 23 interposed between them.
[0014]
In the four-row tapered roller bearing device 2 and the double-row tapered roller bearing device 1, large flange portions 1 b and 2 b with which the large-diameter end surfaces of the tapered rollers are slidably contacted at both outer peripheral ends of the inner rings 11 and 21, respectively. The small flange portions 1c and 2c with which the small diameter side end surfaces of the tapered rollers 13 and 23 abut are provided at positions that are provided and face the large flange portions 1b and 2b across the inner ring raceways 11a and 21a. . The inner ring raceways 11a and 21a are formed to be separated from each other by a predetermined distance corresponding to the width dimension of the outer ring spacers 15 and 25, respectively.
[0015]
In the above configuration, the action lines y1 and y2 of the rolling element load of the double row tapered roller bearing device 1 determined by the inner ring raceway 11a and the outer ring raceway 12a are on the radially outer side of the outer ring 12 as shown in FIG. Intersect.
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 square shape that intersects on the radially inner side of the outer ring 22. Similarly, the other pair of action lines z <b> 3 and z <b> 4 also form an inverted C shape that intersects inside the outer ring 22 in the radial direction.
[0016]
Therefore, 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 central axis A3. That is, the action point distance Z of the rolling element load of the tapered roller 23 on the bearing center side of the four-row tapered roller bearing device is a distance between two points where the action lines z2 and z3 intersect the work roll central axis. The action point distance Y of the rolling element load of the tapered roller 13 of the double row tapered roller bearing device is a distance between two points where the action lines y1 and y2 intersect the work roll central axis A3.
[0017]
If it is the above structure, in the double chock rolling mill provided with the four-row tapered roller bearing device and the double-row tapered roller bearing device, the working point distance Y of the double-row tapered roller bearing device 1 is such that the action lines y1 and y2 are the outer rings. It can be set large enough to cross 12 radial outsides. For this reason, it is possible to easily satisfy Y> 2X.
Therefore, in this double chock rolling mill, the allowable shift amount X is not limited by the operating point distance Y of the double row tapered roller bearing device, but is expanded to the operating point distance Z of the four row tapered roller bearing device. The effect of roll shift can be sufficiently exhibited.
[0018]
【The invention's effect】
As described above, according to the double chock rolling mill according to the present invention , it is possible to prevent a reverse load from occurring even in the double row tapered roller bearing device of the outer chock. Can be suppressed. For this reason, since a large allowable shift amount can be realized without changing the double row tapered roller bearing device to a bearing having a large capacity such as a 4-row tapered roller bearing, the structural change of the rolling mill is not required and is inexpensive. .
[0019]
In addition, according to the double chock rolling mill according to the present invention, 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, so that the uneven load generated when the project block is fixed In contrast, a decrease in bearing life is suppressed. For this reason, wear 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 an essential part showing an embodiment of a bearing portion of a double chock rolling mill according to the present invention.
FIG. 2 is a horizontal cross-sectional view showing a configuration of a conventional double chock rolling mill, in which a pair of work rolls A are arranged side by side in a direction perpendicular to the paper surface. In addition, the cross section regarding one side of a pair of work roll A slid so that it mutually shifted | deviated to the axial direction is shown in the upper half part, and the cross section regarding the other work roll A is shown in the lower half part.
FIG. 3 is a cross-sectional view of a main part of a bearing portion of a conventional double chock rolling mill.
[Explanation of symbols]
1 Double-row tapered roller bearing device 11 Inner ring 11a Inner ring raceway 12 Outer ring 12a Outer ring raceway 13 Tapered roller A Work roll B1 Outer chock B2 Inner chock C Project block Y Working point distance X Shift amount

Claims (1)

In a double chock rolling mill in which both ends of the 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. Chock
An inner ring formed with a pair of conical inner ring raceways having a small diameter at the center of the bearing;
An outer ring disposed concentrically with the inner ring and formed with a conical outer ring raceway facing the inner ring raceway and having a small diameter at the center of the bearing;
Together and a double row tapered roller bearing apparatus Ru and a plurality of tapered rollers interposed respectively between the inner ring raceway and the outer ring raceway opposed thereto,
By intersecting the line of action of the rolling element load of the double row tapered roller bearing device on the radially outer side of the outer ring, the distance of the action point is equal to or greater than the shift amount of the work roll and the four provided on the inner chock. A double chock rolling mill, which is enlarged so as to be equal to or longer than the operating point distance of the row tapered roller bearing device .

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