JP2007319902A - Roll for rolling mill and tension leveler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roll for rolling mills and a tension leveler with which occurrence of scratches and indents on the other roll is prevented and occurrence of a roll crack or the like is suppressed when using this roll together with the other roll. <P>SOLUTION: The roll is provided with a shaft member 50 and a cylindrical roll body 53 which is fit on the shaft member 50 freely rotatably via ball bearings 51 and needle bearings 52. The ball bearing 51 is arranged on the side of the end part in the axial direction of the roll body 53 and also the needle bearing 52 is arranged further on the side of the center in the axial direction than the ball bearing 51. A seal structure part 72 for sealing the opening part 71 at the end in the axial direction of the roll body 53 is arranged further on the side of the end part in the axial direction than the ball bearing 51. A crowning part 56 the length in the axial direction of which is different in the circumferential direction is formed in the end parts in the axial direction of the surface of the outside diameter of the roll body 53. The deepest part in the axial direction of the crowning part 56 is arranged more on the outside in the axial direction than the end face 51b on the side of the end part in the axial direction of the ball bearing 51. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tension leveler that is a device for straightening a steel plate or the like and a roll for a rolling mill that constitutes a backup roll used in the tension leveler.

  In the final step of the rolling operation, stress is removed by passing the workpiece (steel plate or the like) through a straightening machine called a tension leveler to ensure the accuracy of the workpiece. As shown in FIG. 6, there is a tension leveler in which a work roll unit 1 and a deflector roll unit 2 facing the work roll unit 1 are arranged.

  6, the work roll unit 1 includes a work roll 3, an intermediate roll 4, and a backup roll 5, and a deflector roll unit on the opposite side of the work roll unit 1 via a work W (steel plate or the like). Two deflector rolls 6 are arranged.

  That is, the tension leveler directly corrects the workpiece W with the work roll 3, and the intermediate roll 4 and the backup roll 5 support the work roll 3. For this reason, finally, the backup roll 5 supports all loads.

  As shown in FIG. 5, the backup roll 5 includes a shaft member 10 and a cylindrical roll body 13 that is rotatably fitted to the shaft member 10 via a ball bearing 11 and a needle bearing 12. While the ball bearing 11 is disposed on the axial end portion side of the roll body 13, the needle bearing 12 is disposed on the axial center side with respect to the ball bearing 11. Further, a seal structure portion 14 for sealing the axial end opening of the roll main body 13 is provided on the axial end side of the ball bearing 11.

  The axial hole 20 of the roll body 13 includes a small-diameter portion 20a at the axial center portion and a large-diameter portion 20b at the axial end portion side. A stopper 21 made of a flat ring body is attached to the large diameter portion 20b, the ball bearing 11 is disposed axially outward from the stopper 21, and the needle bearing 12 is disposed between the stopper 21 and the small diameter portion 20a. Has been.

  The needle bearing 12 includes a plurality of needle rollers 22 disposed along the circumferential direction on the outer peripheral side of the shaft member 10, and a cage 23 that holds these rollers 22. Spacers 25 and 26 are interposed between the needle bearing 12 and the stopper 21 and between the needle bearing 22 and the end surface of the small diameter portion 20a, respectively.

  The ball bearing 11 includes an inner ring 27, an outer ring 28, and a plurality of balls (balls) 29 interposed between the inner ring 27 and the outer ring 28.

  By the way, if the outer shape of the roll body 13 is a cylindrical shape, a so-called edge load is generated by contact with the intermediate roll 4 as a contact partner roll, and the roll body 13 is interposed between the roll body 13 and the shaft member 10. Among the rolling bearings, the burden on the ball bearings 11 disposed at both ends in the axial direction is increased, and smooth rotation tends to be impaired.

  For this reason, in order to reduce the burden on the ball bearings 11 arranged at both ends in the axial direction, as shown in FIG. .

In that case, an edge load occurs at the boundary portion between the crowning portion 16 and the roll main body 13, but since the boundary portion is usually processed so as to be connected smoothly, compared to the case without the crowning portion. Contact stress due to edge loading can be reduced.
Japanese Patent No. 36747746

  However, when the joint shape is poor or the joint is not properly set at the time of design, stress concentration occurs at the joint, and scratches (indentations) occur from the joint of the crowning portion 16 to the intermediate roll or work roll. Scratches may be transferred to the product (work) and become defective.

  Moreover, the said patent document 1 describes the backup roll in which the crowning part 16 from which axial direction length differs in the circumferential direction is formed. In this way, stress concentration is mitigated by making the axial length different in the circumferential direction. However, in this case, since the axially deepest portion of the crowning portion 16 is set to a dimension that overlaps the ball bearing 11 with the axial insertion position, the roll thickness of the ball bearing insertion portion is reduced. For this reason, the roll strength of the ball bearing insertion portion is reduced, and when a load is applied to the end of the roll due to an unbalanced load, there is a concern about roll cracking from the thin portion of the ball bearing insertion.

  SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a rolling mill roll and a tension leveler that can prevent the occurrence of scratches and indentations on the counterpart roll when used with other rolls, and can suppress the occurrence of roll cracking and the like. I will provide a.

  The roll for a rolling mill according to the present invention includes a shaft member and a cylindrical roll body that is rotatably fitted to the shaft member via a ball bearing and a needle bearing, and the ball bearing is a shaft of the roll body. A roll for a rolling mill, which is disposed on the axial end side of the outer diameter surface of the roll body. In addition to forming a crowning portion having different lengths in the circumferential direction, the axially deepest portion of the crowning portion is disposed axially outward from the end surface on the axial end portion side of the ball bearing.

  According to the rolling mill roll of the present invention, the burden on the ball bearing on the axial end side can be reduced by the crowning portion. In addition, since the axial lengths of the crowning portions are different in the circumferential direction, the places where stress is applied to the counterpart roll are dispersed in the axial direction. Further, by arranging the axially deepest portion of the crowning portion in the axially outward direction from the end surface on the axial end portion side of the ball bearing, it is possible to avoid the crowning portion forming portion from overlapping the ball bearing.

  It is possible to fix the outer ring of the ball bearing to the inner diameter surface side of the roll body and provide a gap between the inner ring of the ball bearing and the outer peripheral surface of the shaft member. Thereby, the ball bearing does not receive a radial load. That is, in this roll for a rolling mill, the radial load is applied to the needle bearing.

  The inner ring of the ball bearing is sandwiched between a stepped portion formed on the outer peripheral surface of the shaft member and a seal structure portion that seals the axial end opening of the roll body closer to the axial end than the ball bearing. By fixing to the shaft member side, a gap can be provided between the inner ring of the ball bearing and the outer peripheral surface of the shaft member.

  The tension leveler according to the present invention is a tension leveler provided with a work roll, an intermediate roll that supports the work roll, and a backup roll that supports the intermediate roll. , Used for the backup roll.

  According to the tension leveler of the present invention, it is possible to reduce the burden on the ball bearing on the axial end side in the backup roll. And the generation | occurrence | production location of the stress to an other party roll (intermediate roll) is disperse | distributed to an axial direction. Furthermore, it is possible to avoid the crowning portion forming portion of the backup roll from overlapping the ball bearing.

  In the roll for a rolling mill of the present invention, the burden on the ball bearing on the axial end side can be reduced by the crowning portion. For this reason, the ball bearing exhibits a stable function over a long period of time. Moreover, the locations where the stress is applied to the counterpart roll are dispersed in the axial direction. For this reason, generation | occurrence | production of the damage | wound of an other party roll and indentation can be prevented. Furthermore, it is possible to avoid the crowning portion forming portion from overlapping the ball bearing. For this reason, the thickness reduction of the ball bearing insertion part can be prevented, and the strength of the roll of the ball bearing insertion part can be increased.

  Since the ball bearing does not receive a radial load, there is no risk of damage due to the radial load, and a stable function can be exhibited as a roll for a rolling mill.

  In addition, since the gap between the inner ring of the ball bearing and the outer peripheral surface of the shaft member can be formed by setting the dimensions of the inner ring of the ball bearing and the outer diameter surface of the shaft member, a gap can be provided easily and reliably. it can.

  According to the tension leveler of the present invention, it is possible to reduce the burden on the ball bearing on the axial end side in the backup roll. Ball bearings exhibit stable functions over a long period of time. And since the generation | occurrence | production location of the stress to an other party roll (intermediate roll) is disperse | distributed to an axial direction, the generation | occurrence | production of the damage | wound of a work roll and an impression can be prevented. Furthermore, the crowning portion forming portion of the backup roll can be prevented from overlapping the ball bearing, and the roll strength of the ball bearing insertion portion can be increased. For this reason, even if the load to the roll end surface is increased due to an offset load generated when the backup roll is inclined, roll breakage is prevented.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

FIG. 1 shows a roll for a rolling mill according to the present invention. The roll for a rolling mill has a shaft member 50 and a cylindrical shape that is rotatably fitted to the shaft member 50 via a ball bearing 51 and a needle bearing 52. The roll main body 53 is provided. The shaft member 50 includes a large-diameter portion 50a at the central portion in the axial direction, a medium-diameter portion 50b on the axial end side, and a small-diameter portion 50c provided between the large-diameter portion 50a and the medium-diameter portion 50b.

  The roll main body 53 is provided with a crowning portion 56 at an axial end portion of the outer peripheral surface 55 thereof. In this case, the crowning portion 56 has a different axial length in the circumferential direction. That is, in the crowning portion 56, the shallowest portion 57b is 180 degrees opposite to the deepest portion 57a, and the joint 57 is continuously formed from the deepest portion 57a to the shallowest portion 57b.

  Moreover, the axial center hole 60 of the roll main body 53 includes a small-diameter portion 60a at the axial center portion and a large-diameter portion 60b at the axial end portion side. The large-diameter portion 60b is provided with a stopper 61 made of a flat ring body, the ball bearing 51 is disposed axially outward from the stopper 61, and the needle bearing 52 is disposed between the stopper 61 and the small-diameter portion 60a. Has been.

  The needle bearing 52 includes a plurality of needle rollers 62 disposed along the circumferential direction on the outer peripheral side of the shaft member 50, and a cage 63 that holds these rollers 32. Spacers 65 and 66 are interposed between the needle bearing 52 and the stopper 61 and between the needle bearing 52 and the end surface 64 of the small diameter portion 60a, respectively.

  As shown in FIG. 2, the ball bearing 51 includes an inner ring 67, an outer ring 68, and a plurality of balls (balls) 69 interposed between the inner ring 67 and the outer ring 68. In this case, the outer ring 68 is press-fitted into the large diameter portion 60 b of the axial hole 60 of the roll body 53, and the end surface (end surface on the stopper side) 68 a of the outer ring 68 is in contact with the stopper 61. Further, a gap 70 is provided between the inner ring 67 of the ball bearing 51 and the outer peripheral surface of the shaft member 50.

  That is, as shown in FIG. 1, a seal structure 72 that seals the axial end opening 71 of the roll body 53 is provided closer to the end in the axial direction than the ball bearing 51. The inner ring 67 of the ball bearing 51 is held between the 50 stepped portions 73. The stepped portion 73 is an end surface of the large diameter portion 50 a of the shaft member 50.

  Further, as shown in FIG. 2, the seal structure 72 includes a rubber seal body 75 having a base portion 75a and a tongue portion 75b, a metal receiving piece 76 that receives the seal body 75, and a metal cover member. 77. As shown in FIG. 1, the cover member 77 includes a short cylindrical portion 78 that is externally fitted to the medium diameter portion 50 b of the shaft member 50, and a flange portion 79 that extends from the short cylindrical portion 78 to the outer diameter side. The part 79 is fitted into the axial end opening 71 of the roll body 53.

  The tongue portion 75 b of the seal body 75 is in close contact with the outer peripheral surface of the short cylindrical portion 78 of the cover member 77. The receiving piece 76 is formed of a ring body having an L-shaped cross section and receives the base portion 75a of the seal body 75, and is press-fitted into the axial end opening 71 of the roll body 53. Further, the base portion 75 a of the seal body 75 is in contact with the end face (end face on the side opposite to the needle bearing) 68 b of the outer ring 68 of the ball bearing 51.

  The inner end 80 of the short cylindrical portion 78 of the cover member 77 is in contact with the end surface (end surface on the side opposite to the needle bearing) 67b of the inner ring 67, and the stepped portion 73 of the shaft member 50 is the end surface of the inner ring 67 (end surface on the needle bearing side). ) 67a.

  The axially deepest portion 57a of the crowning portion 56 is axially outer than the end surface 51b on the axial end portion side of the ball bearing 51 (the end surface disposed on the same surface as the end surface 67b of the inner ring 67 and the end surface 68b of the outer ring 68). It is arranged in the direction. That is, when the dimension from the end surface 81 of the roll body 53 to the axially deepest portion 57a is A, and the dimension from the end surface 81 of the roll body 53 to the end surface 51b on the axial end side of the ball bearing 51 is B, A <B.

  According to the rolling mill roll of the present invention, the crowning portion 56 can reduce the burden on the ball bearing 51 on the axial end side. For this reason, the ball bearing 51 exhibits a stable function over a long period of time. In addition, since the axial length of the crowning portion 56 is different in the circumferential direction, the locations where stress is applied to the counterpart roll are dispersed in the axial direction. For this reason, generation | occurrence | production of the damage | wound of an other party roll and an indentation can be prevented. Further, by arranging the axially deepest portion of the crowning portion 56 in the axially outward direction from the end surface 51b on the axial end portion side of the ball bearing 51, the crowning portion forming portion is prevented from overlapping the ball bearing 51. be able to. For this reason, a reduction in the thickness of the ball bearing insertion portion can be prevented, and the roll strength of the ball bearing insertion portion can be increased.

  Further, it is possible to fix the outer ring of the ball bearing 51 to the inner diameter surface side of the roll body 53 and provide a gap 70 between the inner ring 67 of the ball bearing 51 and the outer peripheral surface of the shaft member 50. As a result, the ball bearing 51 does not receive a radial load, there is no risk of damage due to the radial load, and a stable function can be exhibited.

  The gap 70 between the inner ring 67 of the ball bearing 51 and the outer peripheral surface of the shaft member 50 can be formed by setting the dimensions of the inner ring 67 of the ball bearing 51 and the outer diameter surface of the shaft member 50. This gap 70 can be provided.

  FIG. 3 shows a tension leveler, and this tension leveler includes a work roll unit 91 and a deflector roll unit 92 facing the work roll unit 91.

  The work roll unit 91 includes a work roll 93, an intermediate roll 94, and a backup roll 95. A deflector roll 96 of the deflector roll unit 92 is disposed on the opposite side of the work roll unit 91 via a work W (steel plate or the like).

  And the roll for rolling mills shown in the said FIG. In this case, as shown in FIG. 4, a plurality of rolling mill rolls are arranged in series, and the work roll 93 and the intermediate roll 94 are arranged in parallel.

  In the tension leveler configured as described above, the work W (steel plate or the like) travels between the work roll unit 1 and the deflector roll unit 2 as indicated by the arrows shown in FIG. be able to.

  In the tension leveler of the present invention, since the backup roll 95 uses the roll for rolling mills shown in FIG. 1, the burden on the ball bearing 51 on the axial end side can be reduced in the backup roll 95. In addition, the places where stress is applied to the counterpart roll (intermediate roll 94) are dispersed in the axial direction. Furthermore, it is possible to avoid the crowning portion forming portion of the backup roll 95 from overlapping the ball bearing 51. A reduction in the thickness of the ball bearing insertion portion can be prevented, and the strength of the roll of the ball bearing insertion portion can be increased. For this reason, it is possible to prevent the roll from being damaged when the load on the roll end surface is increased due to the uneven load generated when the backup roll 95 is inclined.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the axial direction of the joint 57 of the crowning portion 56 provided in the roll body 23 The inclination angle α with respect to (see FIG. 1) can be variously changed. At this time, the roll body 23 can be made to differ depending on the outer diameter dimension, the axial length, the material, the workpiece traveling speed, and the like, and the axially deepest portion 57 a is the end surface 51 b on the axial end portion side of the ball bearing 51. It is only necessary to be able to be arranged outward in the axial direction, and to suppress the load on the ball bearings 51 arranged at both ends in the axial direction by suppressing the occurrence of edge load.

  As the seal structure 72, various seals such as a G seal (gasket), a V ring (V packing), a labyrinth seal, an oil seal, a dust wiper, and a cover can be used.

  The roll for the rolling mill is not limited to the backup roll 95 of the tension leveler, but may be used for the intermediate roll 94 and the work roll 93 used for such a tension leveler. Moreover, it is not restricted to a tension leveler, It can be used for various types of rolling such as hot rolling, cold rolling, and warm rolling. Note that hot rolling is rolling performed by heating a metal to a temperature higher than the recrystallization temperature, cold rolling is rolling performed at a temperature lower than the recrystallization temperature, and warm rolling is recovery and recycling. It is rolling performed between crystallization temperatures.

It is a top view shown with the partial cross section of the roll for rolling mills of embodiment of this invention. It is a principal part expanded sectional view of the said roll for rolling mills. It is a simplified diagram of a tension leveler according to an embodiment of the present invention. It is a side view of the work roll unit of the tension leveler. It is a top view shown in the partial cross section of the roll for conventional rolling mills. It is a simplified diagram of a general tension leveler.

Explanation of symbols

50 Shaft member 51 Ball bearing 51b End surface 52 Needle bearing 53 Roll body 56 Crowning portion 57a Deepest portion 67 Inner ring 68 Outer ring 70 Clearance 71 Axial end opening 72 Seal structure portion 73 Stepped portion 93 Work roll 94 Intermediate roll 95 Backup roll

Claims (4)

A shaft member, and a cylindrical roll body that is rotatably fitted to the shaft member via a ball bearing and a needle bearing, and the ball bearing is disposed on the end side in the axial direction of the roll body. A roll for a rolling mill in which the needle bearing is arranged closer to the axial center side than the ball bearing,
A crowning portion having a different axial length in the circumferential direction is formed at an axial end portion of the outer diameter surface of the roll body, and an axial deepest portion of the crowning portion is disposed on the axial end portion side of the ball bearing. A roll for a rolling mill, characterized in that it is disposed axially outward from the end face.   2. The roll for a rolling mill according to claim 1, wherein an outer ring of the ball bearing is fixed to an inner surface of the roll body, and a gap is provided between the inner ring of the ball bearing and the outer peripheral surface of the shaft member. .   A seal structure for sealing the axial end opening of the roll body is provided closer to the axial end than the ball bearing, and an inner ring of the ball bearing is formed on the outer peripheral surface of the seal structure and the shaft member. The roll for a rolling mill according to claim 2, wherein the roll is sandwiched between the stepped portions and fixed to the shaft member side.   In the tension leveler provided with the work roll, the intermediate roll that supports the work roll, and the backup roll that supports the intermediate roll, the roll for a rolling mill according to any one of claims 1 to 3 is used as the backup roll. This is a tension leveler.

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