JP2010042423A - Back-up roll device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a back-up roll device with which the generation of streak marks on a steel sheet or the like of a product is mitigated even when it is used for a tension leveler or the like. <P>SOLUTION: In the back-up roll device 11, a cylindrical roll 13 is installed freely rotatably through ball and roller bearings 14, 15 on the outer periphery of a shaft 12. The intermediate part in the axial direction of the outside diameter surface 13a of the roll 13 is formed into an approximately rectilinear flat part 13aa in a cross-sectional shape and the shaft end parts of the outside diameter surface 13a are taken as a tapered surface drooping part 13ab. The joining part between the flat part 13aa and the surface drooping part 13ab is a projecting curve in the cross-sectional shape and taken as a projecting curve part 13ac which is smoothly connected to the flat part 13aa and the surface drooping part 13ab. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a backup roll device used for a tension leveler or the like in a rolling process of a steel material.

  In the final step of the rolling operation of the steel plate or the like, the stress is removed by passing the leveling material such as the rolled steel plate through a tension leveler that is a straightening machine, thereby ensuring the accuracy of the leveling material. The tension leveler generally includes a work roll, an intermediate roll, and a backup roll as a single unit, and the unit is disposed so as to sandwich the leveling material from above and below in its traveling direction. In this tension leveler, the work roll directly contacts the leveling material to correct the leveling material. The work roll is supported by the intermediate roll and the backup roll, and finally, the backup roll supports all loads.

  FIG. 6 shows a cross-sectional view of a conventional example of a backup roll apparatus in a general tension leveler used in a rolling process of steel materials. In this backup roll device, one ball bearing 35A, 35B is provided on each end of the shaft 32, and two needle bearings 34 are provided on the inner side in the axial direction of each ball bearing 35A, 35B. ing. The roll 33 is rotatably supported on the shaft 32 by these ball bearings 35A, 35B and the needle bearing 34. The two ball bearings 35A and 35B are for applying a thrust load from both axial directions of the shaft 32, and the four needle bearings 34 are for applying a radial load.

In such a conventional backup roll apparatus, on the outer diameter surface 33a of the roll 33, the cross-sectional shape of the intermediate portion in the axial direction is formed into a substantially straight flat portion 33aa (axial width L1), and the outer diameter thereof. The axial end portion of the surface 33a has a tapered shape and is, for example, a surface flared portion 33ab (axial width L3) having an inclination angle of 2 °. Such a shape processing at the shaft end portion of the roll outer diameter surface 33a is also disclosed in Patent Document 1, for example. As shown in FIG. 7 showing an enlarged portion A of one end of the roll 33 in FIG. 6, the joint between the flat portion 33aa of the roll outer diameter surface 33a and the flat surface portion 33ab is smoothly rounded by processing only a lap. ing.
Japanese Patent No. 36747746

  However, as in the conventional example described above, when the joint between the flat portion 33aa of the roll outer diameter surface 33a and the surface smoothing portion 33ab is rounded only by lapping, the rounded shape varies. Also in the backup roll apparatus of Patent Document 1, there is no disclosure about the technology relating to the management of the joint between the flat portion 33aa and the surface flared portion 33ab on the roll outer diameter surface 33a. When the rounded shape is small, the surface pressure of the rounded shape portion is locally increased between the tension leveler and the intermediate roll with which the roll 33 comes into contact, causing contact damage to the intermediate roll. Then, this wound is also transferred to the work roll, and finally, a flaw is generated in the steel plate as the product.

  An object of the present invention is to provide a backup roll device that can reduce the occurrence of bruises on a steel plate of a product even when used for a tension leveler or the like.

The backup roll device of the present invention is a back-up roll device in which a cylindrical roll is rotatably installed on the outer periphery of a shaft via a rolling bearing, and an axially intermediate portion of the outer diameter surface of the roll has a substantially sectional shape. A straight flat portion is formed, the axial end portion of the outer diameter surface is a tapered surface flared portion, and the joint between the flat portion and the surface flared portion is a convex curve. A convex curve portion that smoothly connects the flat portion and the flat surface portion is provided. The above-mentioned "smoothly connect" means that in the cross section including the roll axis, the convex curve forming the cross-sectional shape of the joint is the curve forming the cross-sectional shape of the flat part and the cross-sectional shape of the flattened part. This means that the resulting curve is connected to become a differentiable curve.
According to this configuration, since the joint between the flat portion and the flat surface portion is a convex curve portion that smoothly connects the flat portion and the flat surface portion, even when used in a tension leveler, etc. The surface pressure locally generated at the convex curve portion of the outer surface of the roll can be relaxed between the intermediate roll and the intermediate roll that comes into contact with the roll.
In this configuration, when turning is added to the convex curve portion, the convex curve portion having a desired shape can be accurately obtained compared to the case of only lapping, etc., and the effect of reducing the surface pressure can be achieved. Is definitely obtained. As a result, contact scratches that occur on the intermediate roll can be alleviated, and even if these scratches are transferred to the work roll, the occurrence of bruises on the steel plate of the product can be alleviated.

  In this invention, the roll may be made of hardened steel, and the turning may be hardened steel cutting. In the case of this configuration, it is possible to reduce the occurrence of variation in shape in the processing of the convex curve portion of the roll outer diameter surface, and it is possible to further alleviate the generation of bruises on the steel plate of the product.

  In the present invention, the length in the axial direction of the convex curve portion serving as the joint may be 2 mm or more. When the inclination angle of the surface flared portion on the outer surface of the roll is set to 2 °, for example, if the axial length of the convex curve portion is 2 mm or more (for example, 3.5 mm), the shape of the convex curve portion to be turned Can be made into a stable shape without variation, and the generation of bruises on the steel plate of the product can be further alleviated.

In this invention, the cross-sectional shape of the cross section along the axial direction of the convex curve portion serving as the joint may be one perfect circular arc shape.
When the cross-sectional shape of the cross section along the axial direction of the convex curve portion is an arc shape of one perfect circle, the shape of the convex curve portion to be turned can be made a stable shape with no further variation, It is possible to further alleviate the occurrence of muscle scratches on the steel plate of the product.

  In this invention, the cross-sectional shape of the cross section along the axial direction of the convex curve portion serving as the joint may be a composite arc shape in which a plurality of arcs having different curvature radii are smoothly connected. In the case of this configuration, the degree of freedom in designing the cross-sectional shape of the convex curve portion increases.

  In this invention, the flat part may be a crowning shape having a convex cross section. When the crowning shape is used, even if the roll axis is bent, a uniform pressing force can be obtained over the entire width direction of the rolled steel sheet or the like.

  The backup roll device of the present invention is a back-up roll device in which a cylindrical roll is rotatably installed on the outer periphery of a shaft via a rolling bearing, and an axially intermediate portion of the outer diameter surface of the roll has a substantially sectional shape. A straight flat portion is formed, the axial end portion of the outer diameter surface is a tapered surface flared portion, and the joint between the flat portion and the surface flared portion is a convex curve. Since the convex curve portion is smoothly connected to the flat portion and the flat surface portion, even when used for a tension leveler or the like, it is possible to mitigate the generation of bruises on the steel plate of the product.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic diagram of rolling equipment in the final process of rolling work for steel plates and the like. In this step, the stress of the leveling material 2 such as a steel plate transferred between the upper and lower drive rolls 1 is removed by the tension leveler 3 which is a straightening machine, thereby ensuring the accuracy of the leveling material 2. The The tension leveler 3 includes a plurality of tension leveler units 4 that are arranged above and below the transfer path of the leveling material 2.

  2 and 3 show a side view and a front view of the tension leveler unit 4. The tension leveler unit 4 includes a work roll 5, an intermediate roll 6, and a backup roll apparatus 11 of the present invention. The work roll 5 directly contacts the leveling material 2 to correct the leveling material 2. The work roll 5 is supported by the intermediate roll 6 and the backup roll apparatus 11, and finally all loads are supported by the backup roll apparatus 11.

  FIG. 4 is a sectional view showing an embodiment of the backup roll device 11 of the present invention. In this backup roll device 11, a roll 13 fitted on a shaft 12 is rotatable with respect to the shaft 12 by four roller bearings 14 for radial load loading and two ball bearings 15 for thrust load loading. I support it. Two roller bearings 14 are arranged on both ends of the shaft 12 in the axial direction. The ball bearing 15 is formed of a deep groove ball bearing, and is arranged on the axially outer side of the installation position of the roller bearings 14 arranged two by two. As the ball bearing 15, a four-point contact type ball bearing may be used.

  Since the ball bearing 15 does not apply a radial load, the outer ring 15 b is press-fitted into the inner diameter surface of the roll 13, and a gap is provided between the inner diameter surface of the inner ring 15 a and the outer diameter surface of the shaft 12. The ball bearing 15 is capable of supporting thrust loads in both axial directions (indicated by arrows A and B), and is fixed to the roll 13 and the shaft 12 in both axial directions.

  In this backup roll device 11, the outer diameter surface 13a of the roll 13 is formed such that the cross-sectional shape of the intermediate portion in the axial direction is a substantially straight flat portion 13aa (axial width L2), and the axis of the outer diameter surface 13a The end portion is a tapered shape, for example, a surface flaring portion 13ab (axial width L4) having an inclination angle of 2 °. As shown in FIG. 5 showing an enlarged B portion at one end of the roll 13 in FIG. 4, the joint between the flat portion 13aa of the roll outer diameter surface 13a and the flat surface portion 13ab is a convex curve. A convex curve portion 13ac is smoothly connected to the flat portion 13aa and the flat surface portion 13ab. Here, “smoothly connected” in the expression of the shape of the convex curve portion 13ac means that the curve forming the cross-sectional shape of the cross section including the axis of the roll 13 is connected so as to be a differential curve.

  The roll 13 is made of hardened steel, and the length of the convex curve portion 13ac serving as the joint is 2 mm or longer, and the cross-sectional shape of the cross section along the axial direction is a single circular arc. (R100 to 150). The flat portion 13aa of the roll outer diameter surface 13a has a crowning shape with a convex cross section.

  As described above, in the backup roll device 11, the joint between the flat portion 13aa and the surface flared portion 13ab on the outer surface 13a of the roll has a convex curve and the flat portion 13aa and the surface flared portion 13ab Since the convex curved portion 13ac is smoothly connected to the intermediate roll, the convex curved portion 13ac of the outer surface 13a of the roll is locally generated even when used for a tension leveler or the like. The surface pressure can be relaxed. As a result, contact scratches generated on the intermediate roll can be alleviated, and even if the scratches are transferred to the work roll, the generation of bruises on the steel plate of the product can be reduced.

  Further, in this embodiment, the roll 13 is made of hardened steel, and the turning of the convex curve portion 13ac is made of hardened steel, so that the shape of the convex curve portion 13ac varies in processing. This can further reduce the occurrence of bruises on the steel plate of the product.

  Further, in this embodiment in which the inclination angle of the surface splaying portion 13ab on the roll outer diameter surface 13a is 2 °, the axial length of the convex curve portion 13ac is 2 mm or more (for example, 3.5 mm). The shape of the curved portion 13ac can be a stable shape with no variation, can be further stabilized, and the generation of bruises on the steel plate of the product can be further alleviated.

Moreover, in this embodiment, the cross-sectional shape of the cross section along the axial direction of the convex curve part 13ac used as the joint between the flat part 13aa and the surface shave part 13ab in the roll outer diameter surface 13a is set to one perfect circle. Since it has an arc shape, it is easy to machine, and in this respect as well, the shape of the convex curve portion 13ac to be turned can be made a stable shape without variation, and the generation of bruises on the steel plate of the product is further increased. Can be relaxed.
The cross-sectional shape of the cross section along the axial direction of the convex curve portion 13ac is a composite arc shape in which a plurality of arcs having different curvature radii are smoothly connected in addition to the case where the arc shape is one perfect circle as described above. It is also good. In this case, the degree of freedom in designing the cross-sectional shape of the convex curve portion 13ac is increased.

It is the schematic which shows the equipment of the last process of rolling operations, such as a steel plate. It is a side view of a tension leveler unit. It is a front view of a tension leveler unit. It is sectional drawing of the backup roll apparatus concerning one Embodiment of this invention. It is an expanded sectional view of the B section in FIG. It is sectional drawing of a prior art example. It is an expanded sectional view of the A section in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Backup roll apparatus 12 ... Shaft 13 ... Roll 13a ... Roll outer diameter surface 13aa ... Flat part 13ab ... Flat surface part 13ac ... Convex curve part 14 ... Roller bearing 15 ... Ball bearing

Claims (7)

In a back up roll device in which a cylindrical roll is rotatably installed on the outer periphery of a shaft via a rolling bearing,
An intermediate portion in the axial direction of the outer diameter surface of the roll is formed as a flat portion having a substantially straight cross-sectional shape, and a shaft end portion of the outer diameter surface is formed as a tapered surface beveled portion, and the flat portion and the surface bend. A backup roll device characterized in that the joint between the portions is a convex curve portion having a convex curve in cross-sectional shape and smoothly connected to the flat portion and the flat surface portion.   2. The backup roll device according to claim 1, wherein the convex curve portion is turned.   The backup roll device according to claim 1 or 2, wherein the roll is made of hardened steel, and the turning is a hardened steel cutting.   The backup roll device according to any one of claims 1 to 3, wherein an axial length of the convex curve portion serving as the joint is 2 mm or more.   The backup roll device according to any one of claims 1 to 4, wherein a cross-sectional shape of a cross section along the axial direction of the convex curve portion serving as the joint is a single circular arc.   5. The cross-sectional shape of a cross section along the axial direction of the convex curve portion serving as the joint according to claim 1, wherein the cross-sectional shape is a composite arc shape in which a plurality of arcs having different curvature radii are smoothly connected. A backup roll device. The backup roll device according to any one of claims 1 to 6, wherein the flat portion has a crowning shape with a convex cross section.

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