JPS61154706A - Grinding method of rotating body - Google Patents

Abstract

PURPOSE:To grind efficiently at low cost the outer peripheral surface of a rotating body by pressing a grinding wheel, supported freely rotatably, against the rotating body by offsetting the wheel while slanting it with respect to the rotating body, and producing sliding friction between them. CONSTITUTION:In grinding the outer peripheral surface of a rolling roll 11 by pressing a cylindrical grinding wheel 12, supported freely rotatably, against the roll 11 driven to rotate; the rotating axis (c) of wheel 12 is offset by a quantity (a) with respect to the rotating axis C of roll 11, so as to prevent the extension lines of both axes (c), C from intersecting with each other. Further, the axis (c) is slanted by an angle alpha with respect to the plane P perpendicular to the axis C. Thus, a contact point S between the roll 11 and the wheel 12 forms a contact angle theta with respect to the line L which passes through the axial center (c) and parallel to the axis C, to produce the slide between the roll 11 and the wheel 12, thereby grinding the outer peripheral surface of roll 11 by said sliding friction.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a grinding device for grinding the outer circumferential surface of a rotating object, particularly for use in online grinding of work rolls of rolling mills such as hot rolling mills. It is suitable.

<Prior art> In a hot rolling mill that rolls steel plates, etc., the wear of the work roll during rolling is much greater than that of the backup roll, and the wear of the work roll in particular is rough, especially on the threaded part of the work roll that comes into contact with the strip. There is a tendency for local wear to be large in areas corresponding to the side edges of the strip. For this reason, when rolling strips, schedule rolling is performed in which the rolling order starts from wide strips and then moves to narrow strips, and the rolls are replaced periodically to roll worn rolls. After grinding outside the machine, it was put back into the rolling mill for use.

However, in this method of performing scheduled rolling and grinding the rolls off-line, the rolling order is restricted, which hinders production efficiency, and the rolls must be replaced frequently, requiring a great deal of labor. , which was a major factor in the decline in equipment operating rates. Therefore, progress has been made in the development of an online grinding device that grinds the rolls during rolling while the rolls are still installed in the rolling mill, thereby extending the roll replacement cycle and making it possible to perform rolling operations without restrictions on the rolling order due to strip width. I came.

A conventionally known online grinding device is of the type shown in FIG. 4(a). That is, in the case shown in FIG. 4(a), a prismatic block-shaped grindstone l is pressed against a rotating work roll 2 for grinding.

In the case shown in FIG. 4(b), a disc-shaped grindstone 3 is rotated by a motor (not shown), and is pressed against the surface of a rotating work roll 1 for grinding.

<Problems to be Solved by the Invention> In the case of using the prismatic block-shaped grindstone l shown in FIG. 4(a), the apparatus is simple because there is no need to rotate the grindstone l; Since the grinding wheel 31 is not easily clogged with grinding powder, it is easy to get stuck or burnt, and
Since the grinding wheel 1 has a prismatic shape, its corners are damaged, resulting in a short service life and a drawback that accidents are likely to occur.

On the other hand, in the case of using the disk-shaped grindstone 3 shown in FIG. 4(b), the life of the grindstone 3 is long and the grinding performance is good, but
Since the grindstone 3 must be rotated, the rotating shaft 4 of the grindstone 3 must be rotated by a motor (not shown). Therefore, in addition to requiring a large space in the longitudinal direction of the roll, when a plurality of grinding wheels 3 are arranged, the distance between adjacent grinding stones 3 must be set large, and the distance in the longitudinal direction of the roll is The disadvantage is that it is not possible to grind the entire surface along the .

In view of the above-mentioned drawbacks of the conventional online grinding apparatus, it is an object of the present invention to provide an online grinding method with a simple structure, low cost, and excellent grinding ability.

Ninth Means for Solving the Problems> The rotary body grinding apparatus of the present invention, when pressing a rotatably supported grindstone against the driven and rotating workpiece to grind the outer peripheral surface of the workpiece, The extension of the rotational axis of the grindstone is set so as not to intersect the rotational axis of the object to be ground, and the rotational axis of the grindstone is inclined with respect to a plane perpendicular to the rotational axis of the object to be ground. The present invention is characterized in that the outer circumferential surface of the object to be ground is ground by a grinding edge generated at a contact point between the outer circumferential surface of the object to be ground and the grinding wheel.

Effect> Since the rotation axis of the grindstone is offset from the rotation axis of the workpiece to be ground and is also inclined, sliding friction occurs between the grinding wheel and the outer circumferential surface of the workpiece being driven and rotated. occurs,
This sliding friction automatically grinds the outer peripheral surface of the object to be ground.

<Example> The rotary body grinding method according to the present invention is applied to a rolling roll.
As shown in FIG. 1(a) showing the working concept of the example, FIG. 1(b) showing the sectional structure taken along the line B-B, and FIG. 2 showing the planar shape of FIG. 1(a), The grindstone 12 pressed against the outer circumferential surface of the rolling roll 11 has a cylindrical shape in this embodiment, and is rotatably supported on a support member (not shown) about its rotation shaft 13 . The rotational axis C of the grindstone 12 is offset by a with respect to the rotational axis C of the rolling roll 11, so that the extension of the rotational axis C does not intersect with the rotational axis C.

Further, the rotational axis C of the grinding wheel 12 is inclined by α with respect to a plane (line) p perpendicular to the rotational axis C of the rolling roll 11, so that the contact point between the outer peripheral surface of the rolling roll 11 and the grinding wheel 12 is S is a position that passes through the rotational axis C and is shifted by an angle θ with respect to a line parallel to the rotational axis C.

Therefore, the third
As shown in the figure, when the rolling roll 11 is driven to rotate at a circumferential speed of VR, the grindstone 12 rotates at VG=VH·cosθ, where VG is the rotational speed of the grindstone 12. At this time, if the component force in the direction of the rotation axis C at the contact point S is V3, a slip of VB occurs between the rolling roll 11 and the grindstone 12, but VB = VRSsinθ, and the force direction due to the support member is As a result of the displacement of the grindstone 12 being prevented, the outer circumferential surface of the rolling roll 11 is ground by the frictional force corresponding to this sliding.

In this case, θ
The inclination angle α and the offset amount a of the grindstone 12 may be adjusted so that the values are the optimum values.

Although this embodiment describes the case of grinding a rolling roll of a continuous rolling mill, it is natural that the present invention can be widely applied to grinding the outer circumferential surface of other rotating bodies.

Effects of the Invention> According to the method for grinding a rotating body of the present invention, the grindstone is tilted and offset with respect to the rotating body to generate sliding friction between them, and the outer circumferential surface of the rotating body is ground by this sliding friction. This eliminates the need for a special grinding wheel drive source, making it possible to reduce equipment costs and save space.

[Brief explanation of drawings]

FIG. 1(a) is a conceptual diagram of the working state of one embodiment of the rotary body grinding method according to the present invention, and FIG. 1(b) is the B-
Fig. 2 is a plan view of Fig. 1 (a), Fig. 3 is a working principle diagram showing the grinding principle, Fig. 4 (a),
(b) is a conceptual diagram of a conventional rolling roll grinding method. Also, in the figures, 11 is the rolling roll, 12 is the grindstone, C is the rotational axis of the grindstone, C is the rotational axis of the rolling roll, a is the offset amount, α is the inclination angle, and p is the rotational axis of the rolling roll. The plane S perpendicular to the center is the contact point between the rolling roll and the grindstone, and θ is the contact angle.

Claims (1)

[Claims] When pressing a rotatably supported grindstone against a drive-rotating workpiece to grind the outer peripheral surface of the workpiece, the extension of the rotational axis of the grindstone does not intersect with the rotational axis of the workpiece. and the rotational axis of this grindstone is set to be inclined with respect to a plane perpendicular to the rotational axis of the object to be ground, and the grindstone occurs at the point of contact between the outer peripheral surface of the object to be ground and the grindstone. A method for grinding a rotary body, characterized in that the outer circumferential surface of the object to be ground is ground by sliding.