JP2000317785A - Rotor grinding device and rotor grinding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To individually control the driving states and pressing states of many grinding wheels and to use the grinding wheel arranged in the axial direction of a rotor on the optimum condition by providing a control means independently operating a driving means and a pressing means. SOLUTION: A control device 35 is provided with a press control mechanism 36 and a rotation control mechanism 37. The drive of each cylinder 32 is independently controlled by the press control mechanism 36, and the revolving speed of each motor 30 is independently controlled by the rotation control mechanism 37 according to the grinding needs of a rotor such as the step state of a work roll 21. When the work roll 21 is to be strongly ground, a straight cup grinding wheel 22 is pressed to the work roll 21 at a high pressure by the drive of the cylinder 32, the revolving speed of the motor 30 is properly selected (for determining the ground quantity in a fixed time based on the oscillating speed and pressing force), and the straight cup grinding wheel 22 is driven to implement grinding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating body grinding apparatus and a rotating body grinding method for grinding an outer peripheral surface of a rotating rotating body, and more particularly to an online grinding apparatus for a rolling roll of a cold or hot rolling mill. It relates to an online grinding method.

[0002]

2. Description of the Related Art In a rolling mill for rolling a steel sheet or the like, the outer surface of a rolling roll (work roll) is roughened or worn due to friction with a rolled material. If the surface roughening or wear progresses, the work rolls may be rearranged, but in order to improve the productivity, a so-called online roll grinding device and a so-called online roll grinding method for grinding the outer surface of the work roll with the work roll incorporated in the rolling mill. Conventionally, various proposals have been made.

For example, as disclosed in Japanese Patent Publication No. 5-32126, a method of grinding a roll without externally driving a cup-type grindstone has been proposed by the present applicant. A conventional roll grinding method will be described with reference to FIGS. FIG. 4 is a conceptual view showing the operation state of the conventional roll grinding method, FIG. 5 is a view taken along a line VV in FIG. 4, FIG. 6 is a plan view in FIG. 4, and FIG.

As shown in FIGS. 4 to 6, a grindstone 2 pressed against the outer peripheral surface of a rolling roll 1 is supported by a support (not shown) so as to be rotatable about a rotation shaft 3 thereof.
The rotation axis c of the grinding wheel 2 is offset from the rotation axis C of the rolling roll 1 by a so that the extension of the rotation axis c of the grinding stone 2 does not intersect with the rotation axis C of the rolling roll 1. Has become. The rotation axis c of the grinding wheel 2 is inclined by α with respect to a plane (line) p perpendicular to the rotation axis C of the rolling roll 1, and the contact point S between the outer peripheral surface of the rolling roll 1 and the grinding stone 2 is , And is shifted from the line L parallel to the rotation axis C of the rolling roll 1 by an angle θ.

As shown in FIG. 7, when the rolling roll 1 is driven and rotated at the peripheral speed of Vr, the grinding speed of the grinding wheel 2 is Vg, and the grinding wheel 2 rotates at Vg = Vr · cos θ. At this time, if the component force in the direction of the rotation axis c at the contact point S is Vs, a slip of Vs occurs between the rolling roll 1 and the grindstone 2,
Vs = Vr · sin θ, and the displacement of the grindstone 2 in the Vs direction is prevented by the support member. As a result, the outer peripheral surface of the rolling roll 1 is ground with a frictional force corresponding to the slip. By appropriately adjusting the angle θ, the inclination angle α, and the offset amount a,
Optimum grinding conditions can be obtained.

Further, as disclosed in Japanese Patent Publication No. 4-62804, a grinding apparatus in which a plurality of cup-shaped grindstones are effectively arranged on one work roll has been proposed by the present applicant. I have. A conventional roll grinding device will be described with reference to FIG. FIG. 8 shows a schematic configuration of a conventional roll grinding apparatus.

As shown in the figure, a plurality of (six in the illustrated example) cup grindstones 6 are arranged in a longitudinal direction of a work roll 5 by a first group 6a, 6b, 6c and a second group 6d, 6e, 6f. It is arranged as. Each of the cup grindstones 6a to 6f has a rotation axis C1, C2, C3, C
4, C5 and C6 obliquely intersect the axis C of the work roll 5. The angle α of the work roll 5 with respect to the perpendicular to the axis C is defined by the work side (WS) side and the drive side (DS) with respect to the longitudinal center portion M of the work roll 5 as a boundary.
The angle is set symmetrically with the side.

That is, with the center M in the longitudinal direction of the work roll 5 as a boundary, the rotation axes C1, C of the first groups 6a, 6b, 6c on one side are arranged.
Reference numerals 2 and C3 are set so as to intersect with the central portion M and obliquely intersect with the axis C of the work roll 5 at an angle α. Further, with the center part M in the longitudinal direction of the work roll 5 as a boundary, the rotation axes C4, C5, C6 of the second group 6d, 6e, 6f on the other side are in a direction intersecting with the center part M, and The rotation axis C1, C2, and C3 are set so as to obliquely intersect with the axis C of the work roll 5 at an angle α opposite to the axis of rotation C1, C2, and C3. As a result, the first group 6a, 6b, 6c and the second group 6d, 6e, 6f are symmetrical with respect to the central portion M and are arranged in such a direction that their respective contact end faces face each other.

In such an arrangement, the cup grinding stones 6a, 6b, 6c,
And 6d, 6e, 6f rotate I-II, II-III, II
The work roll 5 is reciprocated between the I-M, M-IV, IV-V, and V-VI by a moving device (not shown) to grind the outer peripheral surface of the work roll 5. Accordingly, the work roll 5 can be ground to the ends on both sides of the work side and the drive side, the cup grindstones 6a and 6f located at both ends do not protrude from the side ends of the work roll 5, and the rotating mechanism is the main body of the rolling mill. , And uniform grinding can be performed over the entire length of the work roll 5 in the longitudinal direction.

Further, as disclosed in Japanese Patent Publication No. 5-34087, a roll grinding method for controlling the grinding characteristics by driving or braking a cup-type grindstone has been proposed by the present applicant. A conventional roll grinding method will be described with reference to FIGS. FIG. 9 shows the mechanism concept of the conventional roll grinding method, FIG. 10 shows its side surface, FIG. 11 shows its plane, FIG. 12 shows the principle of the grinding speed, FIG. FIG. 14 shows the side view, FIG.
FIG. 5 shows the principle of the grinding speed.

As shown in FIGS. 9 to 15, the cup-type grindstone 11 has a relatively small (usually about 1 kW) electric or hydraulic motor 12, and has an appropriate grindstone rotation speed and an appropriate grindstone rotation speed in accordance with the peripheral speed of the work roll 13. And the rotation axis of the cup-type grindstone 11 is inclined by an angle α with respect to the axis normal of the work roll 13, and the work roll 13 is offset by a distance a with respect to the horizontal plane of the work roll 13. And reciprocate in the axial direction of the work roll 13. Here, as shown by the center S of the contact line between the cup-type grindstone 11 and the work roll 13, the work roll 1
The point is shifted from the third axis by an angle θ. Further, a motor 12 that supports the cup-type grindstone 11 is supported by a housing 14 of the grinding device, and reciprocates in the axial direction of the work roll 13 by a moving device (not shown) along a fixed guide beam (not shown). Is ground to the required profile.

With such a configuration, when the work roll 13 is rotated at the peripheral speed Vr in a state of being incorporated in a rolling mill, the cup-type grindstone 11 can rotate freely when the grindstone is rotated and driven.
Vg1 = Vr · cos which is a tangential component passing through the center S of the contact line
It rotates at the speed of θ. Here, a rotation speed Vg = Vg1 different from the driven rotation speed Vg1 by the motor 12 is applied to the cup-shaped grindstone 11.
By giving + Vg2, the relative sliding speed Vs between the cup-shaped grindstone 11 and the surface of the work roll 13 is increased in the case of the driven rotation.

(Equation 1) That is, Vs = Vr · sin θ becomes larger,

(Equation 2) That is,

(Equation 3) Becomes

The relative sliding speed Vs is equal to or smaller than the cup type grinding wheel 11.
Is the grinding speed when the surface of the work roll 13 is ground. Generally, in the grinding process, it is considered that the grinding speed is preferably higher within a range in which the grindstone does not break or seize, and grinding characteristics such as grinding ability and grinding ratio are strongly affected by the grinding speed. In order to maintain the grinding characteristics stably, it is necessary to control the relative slip speed Vs by changing the grinding wheel rotation speed Vg1 + Vg2 in accordance with the change in the peripheral speed Vr of the work roll 13 which changes according to the rolling conditions.

In this conventional example, by controlling the change in the wheel rotation speed Vg2 within the capacity of the motor 12, it is possible to increase the grinding speed and stabilize the grinding characteristics adapted to the change in the roll peripheral speed. Incidentally, the change amount Vg2 of the grinding wheel rotation speed may be either positive (increase) or negative (deceleration), and the offset amount a and the inclination angle α are the shape and characteristics of the grinding wheel, the diameter and the peripheral speed of the work roll 13, and the like. Thus, it can be set so that the grinding characteristics such as the grinding ability and the grinding ratio are appropriate.

[0015]

In recent years, there has been an increasing demand for installing an on-line grinding apparatus even in a plate rolling mill having a long body length of a work roll (for example, more than 5 m). Naturally, it is necessary to dispose a large number of cup-shaped grindstones for the longer body length. The purpose of on-line roll grinding in the case of a plate rolling mill is to remove the fatigue layer that develops on the roll surface as the rolling progresses, and to reduce the roll surface step due to the grinding of the roll part (the part that does not wear) where the rolled material does not contact during rolling. Removal. This step occurs at a position corresponding to the width of the rolled material. Accordingly, it is necessary to change the grinding conditions for a large number of cup-shaped grindstones depending on the roll position corresponding to the cup-shaped grindstones. In other words, it is necessary to use each cup-type grindstone most effectively.

The above-described conventional grinding apparatus and grinding method include:
Since multiple whetstones had the same structure and the same use,
Each whetstone could not be used under optimum conditions. For this reason, the conventional grinding device and grinding method cannot be applied to online grinding of a plate rolling machine having a long trunk, and it is not possible to effectively grind a work roll of a plate rolling machine having a long trunk. could not.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a rotating body grinding apparatus and a rotating body grinding method that can use a plurality of grinding wheels individually under optimum conditions.

[0018]

To achieve the above object, a rotating body grinding apparatus according to the present invention comprises a plurality of grinding wheel support portions movable in the axial and radial directions of the rotating body in the axial direction of the rotating body. Provided, a grindstone shaft to which a grinding grindstone is attached is rotatably provided in each grindstone support portion, and a driving means for driving and rotating the grindstone shaft is provided in each grindstone support portion, and a clutch means is provided between the driving means and the grindstone shaft. While each intervenes,
Pressing means for moving the grindstone support portion in the normal direction of the rotating body to press the grinding wheel against the rotating body is provided, and control means for operating the driving means and the pressing means independently is provided.

The control means independently controls the driving means and the pressing means on the basis of the grinding needs of the rotating body, so that the pressing force and the rotational driving force of the grinding wheel in the axial direction of the rotating body can be controlled by each grinding wheel support. And a function of selecting the driving grinding by driving by the driving means and the pressing by the pressing means and the non-driving grinding by the pressing and co-rotation by the respective wheel supporting portions.

Further, in the rotating body grinding method of the present invention for achieving the above object, a number of grinding wheels are arranged in the axial direction of the rotating body, and the plurality of grinding wheels are independently moved in a normal direction. And adjusts the pressing force, and independently adjusts the rotation state of each grinding wheel.

Based on the grinding needs of the rotating body, the driving condition of the grinding wheel and the pressing force of the grinding wheel are independently adjusted in each of the grinding wheel supports, and according to the axial position of the rotating body, the grinding wheel is driven and pressed. The grinding of the rotating body is performed by selecting driving grinding and non-driving grinding by pressing and co-rotation at each grinding wheel support.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotary body grinding apparatus and a rotary body grinding method according to the present invention will be described with reference to FIGS. The illustrated example shows an example in which a work roll of a thick plate rolling mill having a long body length is applied as a rotating body. FIG. 1 is a cross-sectional view of a main part of a rotary body grinding device according to an embodiment of the present invention, FIG. 2 is a concept showing the arrangement of grinding wheels, and FIG. 3 is a concept of wear and fatigue layers generated on the roll surface. Is shown.

As shown in FIG. 2, the body length is long, for example,
A large number (12 in the illustrated example) of cup grinding wheels 22 as grinding wheels are arranged in the longitudinal direction of the work roll 21 exceeding 5 m, and six cup grinding wheels 22 on the work side (WS) side are provided.
And the six cup grindstones 22 on the drive side (DS) side are set so as to obliquely cross each other at a symmetrical inclination angle with respect to the central portion M and face each other (for details, see FIG. reference). Further, the offset amount between the rotation axis of the work roll 21 and the rotation axis of the cup grindstone 22 and the like are appropriately set as described in the above-described conventional example.

The main part of the rotary body grinding apparatus will be described with reference to FIG. As shown in the drawing, a guide portion 24 extending in the longitudinal direction of the work roll 21 is formed on a gantry 23 of the plate rolling mill, and a frame 25 is movably supported by the guide portion 24. The frame 25 is provided with 12 grindstone housings 26 as grindstone support portions in the longitudinal direction of the work roll 21. Each grindstone housing 26 is attached to the work roll 21 with respect to the
Are supported so that they can reciprocate in the radial direction.

Each of the grinding wheel housings 26 has a bearing 2
8, the grinding wheel shaft 29 is rotatably supported, and the grinding wheel shaft 2
9 is provided with a cup grindstone 22 facing the work roll 21. An output shaft of a motor 30 as a driving means is provided on the grinding wheel shaft 29 with a clutch 31 as a clutch means.
And the driving force of the motor 30 is transmitted to the grinding wheel shaft 29 or not.

On the other hand, a main body 33 of a cylinder 32 as a pressing means is fixed to the frame 25 at a position corresponding to each grinding wheel housing 26, and a tip of a rod 34 of the cylinder 32 is fixed to the grinding wheel housing 26. In other words, the grinding wheel housing 3
6 is reciprocated in the radial direction of the work roll 21, that is, the pressing force of the cup grindstone 22 against the work roll 21 is adjusted.

The drive control of the motor 30 (control of the number of rotations) and the drive control of the cylinder 32 (adjustment of the pressing force of the cup grindstone 22) are performed independently for each grindstone housing 26 by a command from the control device 35. You. The control unit 35 receives the width information of the work roll 21 rolled by the plate rolling mill or the profile detection information of the work roll 21 by the profile meter, determines the level of the work roll 21, and recognizes the need for grinding the work roll 21. Is done. The control device 35 is provided with a pressing control function 36 and a rotation control function 37. The pressing control function 36 and the rotation controlling function 37 are performed in accordance with the needs of grinding the rotating body such as the level of the work roll 21.
, The driving of each cylinder 32 is independently controlled, and the rotation control function 37 independently controls the rotation speed of each motor 30.

That is, when the work roll 21 is strongly ground, the cylinder 32 is driven to rotate the cup grindstone 22.
Is pressed against the work roll 21 at high pressure and the motor 3
The rotation speed of 0 is appropriately selected (selected to determine the grinding amount within a certain time from the oscillation speed and the pressing force),
The drive grinding is executed by driving the cup grindstone 22. When the work roll 21 is lightly ground, the cylinder 32 is driven to press the cup grindstone 22 against the work roll 21 at a low pressure, and the drive of the motor 30 is turned off.
The non-drive grinding is performed by rotating the cup grindstone 22. The pressing force of the cup grindstone 22 against the work roll 21 by driving the cylinder 32 and the driving of the motor 30 are:
The control unit 35 controls each of the grindstone housings 26 according to the position of the step of the opposing work roll 21 or the position of the wear portion.

In the above-described embodiment, an example is shown in which the clutch 31 is applied as the clutch means that does not transmit power at least from the grindstone shaft 29 side to the motor 30 side. It is also possible to apply When the speed change means having a neutral state is applied, the rotation speed of the cup grindstone 22 can be controlled by controlling the speed change means while keeping the rotation speed of the motor 30 constant.

A method of grinding a rotating body by the rotating body grinding apparatus having the above-described configuration will be specifically described. As shown in FIG. 3, as the rolling progresses, a step is generated between the passing portion 21 a and the non-passing portion 21 b of the work roll 21. As the passing plate portion 21a wears, the fatigue layer 21c increases toward the inside at the same time.
If c is removed before it increases, the generation and increase of the fatigue layer 21c can be suppressed. Since the non-passing portion 21b does not contact the rolled material and does not wear, the non-passing portion 21a and the non-passing portion do not wear.
There is a step at the boundary of 21b. That is, it is necessary to grind the non-passing portion 21b to the passing portion 21a in preparation for the next rolling of the wide material.

As shown in FIG. 2, 12 cup grindstones 22 are arranged in the axial direction of the work roll 21. The work roll 2 is controlled by the controller 35 according to the width information of the rolled sheet or the profile detection information by the profile meter.
The first passing portion 21a and the non-passing portion 21b are identified, and drive grinding or non-drive grinding is individually performed by the respective cup grindstones 22. More specifically, non-drive grinding is performed on the passing plate portion 21a so that the cup grindstone 22 is caused to rotate.
The drive grinding is performed by rotating the drive by 0.

More specifically, in the case of a plate rolling mill, since the usual minimum plate width is about 2 m, three zones are set in the axial direction of the work roll 21. That is, the area of about 2 m in the central portion is set as the A zone, both sides of the A zone are set as the B zones, and both sides of the B zone are set as the C zones. In zone A, in order to always cope with the removal of the fatigue layer, non-drive grinding of weak grinding is performed by pressing with low pressure. Zone B is a range in which a step is generated depending on the width of the strip to be rolled. Therefore, based on the strip width information or profile detection information by a profile meter, non-drive grinding of weak grinding with low pressure pressing and strong grinding with high pressure pressing. And drive grinding. The C zone is the range of the end portion of the work roll 21 and becomes a non-threaded portion in most of rolling, so that the driving grinding of the strong grinding is performed by high-pressure pressing.

When the driving grinding and the non-driving grinding are performed, the number of rotations, the rotation force, the braking force, the pressing force of the cup grindstone 22 and the like of the motor 30 are controlled individually as appropriate. Used under the optimal conditions required. In the above embodiment, an example in which twelve cup grinding wheels 22 are provided has been described, but the number of cup grinding wheels 22 is 12
It is not limited to an individual. For example, when four cup grindstones 22 are applied, drive grinding is performed with two outer cup grindstones 22, and grinding is performed with two inner cup grindstones 22 by switching between drive grinding and non-drive grinding. You may. When six cup grindstones 22 are applied, drive grinding is performed with the two outer cup grindstones 22, non-drive grinding is performed with the two inner cup grindstones 22, and two intermediate cup grindstones 22 are used. May be switched between driving grinding and non-driving grinding to perform the grinding.

In the rotating body grinding method using the rotating body grinding apparatus described above, the driving state and the pressing state of the twelve cup grinding stones 22 are individually controlled, so that the cup grinding stones 22 arranged in the axial direction of the work roll 21 can be removed. The work rolls 21 of a thick plate rolling mill having a long body length can be effectively ground, which can be used properly under respective optimum conditions. In addition, it is possible to improve the unit consumption of the work roll 21 and the cup grindstone 22.

[0035]

According to the rotating body grinding apparatus of the present invention, a large number of grindstone support portions movable in the axial direction and the radial direction of the rotating body are provided in the axial direction of the rotating body. The grindstone support is rotatably provided on the grindstone support, and drive means for driving and rotating the grindstone shaft are provided on the grindstone support, respectively. Pressing means for moving the grinding wheel against the rotating body by moving in the linear direction is provided, and control means for operating the driving means and the pressing means independently are provided, so that the driving state and the pressing state of a large number of grinding wheels can be individually determined. Can be controlled. As a result,
The grinding wheels arranged in the axial direction of the rotating body can be properly used under optimum conditions, and work rolls of a thick plate rolling mill having a long body length can be effectively ground.

The control means controls the driving means and the pressing means independently based on the grinding needs of the rotating body, so that the pressing force and the rotational driving force of the grinding wheel in the axial direction of the rotating body can be controlled by each grinding wheel support. Each of the grinding wheels has a function of selecting the driving grinding by driving by the driving means and the pressing by the pressing means and the non-driving grinding by the pressing means and the co-rotation at each grinding wheel support. It is possible to selectively and individually control the driving state and the pressing state.

In the method for grinding a rotating body according to the present invention, a large number of grinding wheels are arranged in the axial direction of the rotating body, and the pressing force is adjusted by independently moving the plurality of grinding wheels in the normal direction. Since the rotation state of each grinding wheel is adjusted independently, the driving state and the pressing state of many grinding wheels can be individually controlled. As a result, the grinding wheels arranged in the axial direction of the rotating body can be used properly under optimum conditions, and the work roll of the thick plate rolling mill having a long trunk length can be effectively ground.

Then, based on the grinding needs of the rotating body, the driving condition of the grinding wheel and the pressing force of the grinding wheel are independently adjusted at each grinding wheel support portion, and the grinding wheel drive and the grinding wheel drive are adjusted according to the axial position of the rotating body. Since the grinding of the rotating body is performed by selecting the driving grinding by pressing and the non-driving grinding by pressing and co-rotation at each grinding wheel support, the driving state and the pressing state of a large number of grinding wheels are selectively and individually. It becomes possible to control.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a rotary body grinding device according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram illustrating an arrangement state of a grindstone.

FIG. 3 is a conceptual diagram of a wear and fatigue layer generated on a roll surface.

FIG. 4 is a conceptual diagram showing an operation state of a conventional roll grinding method.

FIG. 5 is a view taken along line VV in FIG. 4;

FIG. 6 is a plan view in FIG. 4;

FIG. 7 is an explanatory diagram of a grinding principle.

FIG. 8 is a schematic configuration diagram of a conventional roll grinding device.

FIG. 9 is a conceptual view of a mechanism of a conventional roll grinding method.

FIG. 10 is a side view in FIG. 9;

FIG. 11 is a plan view in FIG. 9;

FIG. 12 is a principle diagram of a grinding speed.

FIG. 13 is a conceptual diagram of a mechanism for braking a grindstone.

FIG. 14 is a side view of FIG.

FIG. 15 is a principle diagram of a grinding speed.

[Explanation of symbols]

 Reference Signs List 21 work roll 22 cup grindstone 23 gantry 24 guide part 25 frame 26 grindstone housing 27 guide roller 28 bearing 29 grindstone shaft 30 motor 31 clutch 32 cylinder 33 main body 34 rod 35 control device 36 pressing control function 37 rotation control function

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Makoto Miyake 4-6-22 Kannonshinmachi, Nishi-ku, Hiroshima-shi, Hiroshima F-term in Mitsubishi Heavy Industries, Ltd. Hiroshima Works 3C043 AC13

Claims (4)

[Claims] 1. A large number of grindstone support portions movable in the axial direction and the radial direction of a rotating body are provided in an axial direction of a rotating body, and a grindstone shaft to which a grinding wheel is attached is rotatably provided on each grindstone support portion. A driving means for driving and rotating the grinding wheel shaft is provided in each of the grinding wheel supports, and a clutch means is interposed between the driving means and the grinding wheel shaft, respectively, while the grinding wheel support is moved in the normal direction of the rotating body to form the grinding wheel. A rotating body grinding apparatus comprising: pressing means for pressing the rotating body; and control means for operating the driving means and the pressing means independently. 2. The method according to claim 1, wherein the control means controls the driving means and the pressing means independently based on the grinding needs of the rotating body, so that the pressing force and the rotational driving force of the grindstone in the axial direction of the rotating body are provided. Is adjusted at each whetstone support,
A rotating body grinding apparatus having a function of selecting, at each grinding wheel support portion, driving grinding by driving by driving means and pressing by pressing means and non-driving grinding by pressing and co-rotation by pressing means. 3. A plurality of grinding wheels are arranged in the axial direction of the rotating body, and the pressing force is adjusted by independently moving the plurality of grinding wheels in the normal direction. A rotating body grinding method characterized by independently adjusting the rotation speed. 4. The method according to claim 3, wherein the grinding wheel driving rotation state and the grinding wheel pressing force are independently adjusted in each grinding wheel support portion based on the grinding needs of the rotating body, and according to the axial position of the rotating body, A rotating body grinding method characterized in that the rotating body is ground by selecting driving grinding by driving and pressing by a grinding wheel and non-driving grinding by pressing and rotating in each wheel supporting portion.