JP2004136438A - Polishing method of roll for rolling - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of polishing a roll for simply and efficiently applying uniform cloth polishing to a roll peripheral surface without unevenness in polishing. <P>SOLUTION: When an offset amount of a whetstone 2 is more than 0 and less than 1/2 of the outer diameter of the whetstone and the whetstone is equally divided by a plane including the circumference of a roll 1 for rolling, the whetstone is brought into contact with the roll so that a contact surface between the whetstone and the role exists on both sides of the equally dividing line. In addition, the rotation axis of the whetstone is inclined so that the pressure of the contact surface in the forward direction of the whetstone moving direction is higher than that in the backward direction of the moving direction. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a rolling roll used for rolling a high-gloss metal plate and a method for polishing the same, comprising: , A cross-polishing pattern) on the roll peripheral surface.

  On the metal plate surface after cold rolling, there are micro defects having a depth of about several μm called oil pits and micro defects having a depth of about 1 μm due to the transfer of the polished eyes of the roll called scratches. This causes the surface gloss to decrease. Therefore, various rolling methods have been proposed to smooth the surface of the metal plate during cold rolling and to suppress the occurrence of micro defects called oil pits and scratches. It has been proposed to apply eyes to a rolling roll (hereinafter, also simply referred to as a roll) to obtain a high-gloss metal plate having a small surface roughness.

For example, Japanese Patent Application Laid-Open No. 8-267109 discloses that a lapping film is applied to a roll with a cross-polished grain inclined at an angle of 30 ° or more with respect to the circumferential direction, and a cold-rolled steel sheet is rolled using this roll, thereby providing excellent gloss. It is disclosed that a metal plate is obtained (Patent Document 1).

Further, Japanese Patent Application Laid-Open No. 5-253604 discloses that a regular roll grinder is used to control the rotation speed of a work roll and the feed speed of a grindstone to give a spiral mark-shaped abrasive to the roll. There is disclosed a cold rolling method for obtaining a metal plate having excellent gloss by using the same (Patent Document 2).

Further, as disclosed in Japanese Patent Application Laid-Open No. 7-265912, as shown in FIGS. 7A and 7B, a disc-shaped (including a hollow disc-shaped (also called a cup-shaped)) grindstone 20 is used, and the offset of the grindstone is performed. The amount is X, and the inclination angle with respect to the normal 10N of the roll is φ, and one end P of the rotated grindstone 20 is brought into contact with the rotating roll surface, and the grindstone 20 is relatively moved in the direction of the roll axis 10A. As shown in FIG. 8, there is disclosed a method of polishing a roll in which a circumferential surface of the roll 10 is provided with a polishing grain inclined in one direction with respect to the circumferential direction of the roll, and a rolling method using the roll (Patent Document 1). 3).
JP-A-8-267109 JP-A-5-253604 JP-A-7-265912

  However, the polishing method disclosed in Japanese Unexamined Patent Application Publication No. 8-267109, which provides a cross-polishing line with a wrapping film, moves the wrapping film in the axial direction of the roll while pressing the wrapping film against the roll to give a slight vibration in the axial direction of the roll. Because the control is complicated and the abrasive grains of the wrapping film are easily worn out, it is necessary to frequently change the wrapping film, the polishing efficiency is poor, and the wrapping film is caused to vibrate in the axial direction of the roll. As a result, polishing unevenness (polishing pattern on appearance and unevenness of roll surface roughness) is likely to occur on the peripheral surface of the roll, and there has been a problem that a metal plate rolled using this roll has uneven gloss.

  In the polishing method for imparting a spiral abrasive grain disclosed in Japanese Patent Application Laid-Open No. 5-253604, for example, when imparting a 30 ° inclined abrasive grain, the grindstone is rolled at a high speed of 0.68 times the outer peripheral speed of the roll. Since it is moved in the axial direction, there is a problem that polishing failure called "hitting" is likely to occur, and there is a problem that remarkable polishing unevenness occurs, and gloss unevenness is clearly transferred to a metal plate rolled using this roll. However, there was a problem that the product was not produced due to uneven gloss.

In addition, in the polishing method disclosed in Japanese Patent Application Laid-Open No. 7-265912, only a polishing grain inclined only to one side with respect to the circumferential direction can be applied to the roll, and when this rolling roll is used, meandering occurs during rolling. This causes a problem that a rolling trouble occurs.

Therefore, an object of the present invention is to solve the above-mentioned problems in the roll polishing method of the prior art, and to easily and efficiently apply a uniform cross-polished stitch to the roll peripheral surface without polishing unevenness. It is to provide a method.

The present invention uses a hollow disk-shaped whetstone, while rotating the whetstone, while contacting the roll for rotation, and further relatively moving in the axial direction of the roll for polishing the roll for roll When the offset amount of the whetstone is greater than 0 and less than 1/2 of the outer diameter of the whetstone, and when the whetstone is equally divided on a surface including the circumference of the rolling roll, contact between the whetstone and the rolling roll The whetstone is brought into contact with the roll for rolling so that a surface is present on both sides of the bisector, and the rotation axis of the whetstone is moved, and the surface pressure of the contact surface in front of the moving direction of the whetstone is such that the whetstone moves. A method for polishing a roll for rolling, characterized in that the roll is polished in the moving direction so as to be higher than the surface pressure of the contact surface at the rear of the rolling roll.

ADVANTAGE OF THE INVENTION According to the polishing method of this invention, a uniform cross-polishing pattern without polishing unevenness is easily given to a roll peripheral surface only by moving a grindstone at least once in the axial direction of a rolling roll. Can be.

The method of polishing a rolling roll (hereinafter, also simply referred to as roll 1) for cold rolling a stainless steel sheet according to the present invention is a hollow disk-shaped grinding wheel (hereinafter, simply referred to as a grinding wheel) used for mirror-finishing the roll. This is a polishing method completed by focusing on (1), and simply and efficiently giving a cross-polished stitch to the roll without polishing unevenness.

Hereinafter, the method for polishing a roll of the present invention will be described in detail with reference to the drawings.

First, using FIG. 1 to FIG. 3 and FIG. 5, a cross-polished stitch is applied to a flat roll (a roll 1 formed by rotating a straight line parallel to the roll axis around the roll axis). As shown in FIG. 4, in the present invention, a case where the roll is applied is a roll with a curve (a roll 1 whose peripheral surface is formed by rotating a curve along the roll axis around the roll axis). The cloth may be provided with a cross polishing grain.

FIG. 1 is a diagram showing a polishing state in a case where the roll 1 is polished without inclining the rotation axis 2A of the grindstone 2 with respect to the normal 1N of the roll 1 in the moving direction, and FIG. 1B is a partial plan view showing a contact state between the grindstone 2 and the roll 1, FIG. 1B is a partial sectional view taken along line BB, and FIG. 1C is a sectional view taken along line AA. FIG. 2 is a plan view showing the direction of the circumferential velocity vector of the grindstone on the contact surface between the grindstone 2 and the roll 1. FIG. FIG. 2 is a developed schematic view of the surface of the roll 1 showing an angle.

Here, FIG. 5 is a schematic diagram showing a polishing state when the rotation axis 2A of the grindstone 2 is inclined in the moving direction with respect to the normal 1N of the roll 1 in FIG. 1, FIG. 2 or FIG. is there.

Reference numeral 1A denotes a rotation axis of the roll 1 (hereinafter simply referred to as a roll axis or axis), 1B denotes a rotation direction of the roll 1, 1N denotes a normal line of the roll 1, and reference numeral 2A denotes a rotation axis of the grinding wheel 2 (hereinafter simply referred to as a grinding wheel). 2B is the rotation direction of the grindstone 2, 2C is the moving direction of the grindstone 2, 2D is a line equally dividing the contact area between the grindstone 2 and the roll 1 in the direction of the roll axis 1A), 3L and 3R are This is the contact surface between the grindstone 2 and the roll 1. If the whetstone 2 is equally divided on a virtual surface including the circumference of the roll 1, the dividing line becomes exactly 2D. X is the offset amount, θ1 and θ2 are the directions of the outer peripheral velocity vector of the grindstone 2 and the inner peripheral velocity vector of the grindstone 2 on the contact surface between the grindstone 2 and the roll 1, respectively, and θ ⁺ and θ ⁻ One inclination angle and the other inclination angle of the applied cross polishing eye.

As shown in FIG. 1, the grindstone 2 used in the present invention has a ring-shaped polishing surface provided so as to be orthogonal to the axis 2A, and a rotating mechanism (not shown) of the grindstone 2 is provided on a plate surface opposite to the polishing surface. It is attached. To grind the roll 1 using this grindstone 2, the grindstone 2 is attached to a grindstone rotating mechanism of a roll grinder (not shown), and the roll 1 is attached to the same roll grinder, and a roll rotating mechanism (not shown) is used. Then, the grindstone 2 is rotated and the roll 1 is brought into contact with the roll 1, and the roll 1 is polished by relatively moving in the roll axis 1A direction.

At that time, as shown in FIG. 1, the roll 1 polishing method of the present invention sets the offset amount X of the grindstone 2 to be more than 0 and less than 1/2 of the outer diameter of the grindstone 2, and the contact surface between the grindstone 2 and the roll 1 The grindstone 2 is brought into contact with the roll 1 so that the grindstone 2 is present on both sides of the dividing line 2D, and the rotating shaft 2A of the grindstone 2 is inclined in the moving direction with respect to the normal 1N of the roll 1 as shown in FIG. In this way, a cross-polishing line is provided on the peripheral surface of the roll. 1 and 5, 3L and 3R denote contact surfaces between the grindstone 2 and the roll 1, and the contact surfaces 3L and 3R equally divide the grindstone 2 by a surface including the circumference of the roll 1 in the direction of the roll axis 1A. Exist on both sides of the contour line 2D.

Here, in order to bring the polished surface of the grindstone 2 into contact with the roll 1 as described above, the polished surface of the grindstone 2 is turned to the roll 1 and the axis 2A of the grindstone 2 is set to the roll normal 1N in a roll polisher (not shown). Then, the grinding surface of the grindstone 2 may be brought into contact with the roll 1 by being shifted in parallel by the offset amount X, thereby simplifying the process. In the roll polishing machine, the polishing surface of the grindstone 2 is directed to the roll 1, and the axis 2A of the grindstone 2 is made to coincide with the roll normal 1N, and then shifted in parallel by the same offset amount as described above. The above-mentioned polishing state can be obtained even when the roll 2 is brought into contact with the polished surface of the grindstone 2 on both sides of the surface perpendicular to the axis 1A of the roll 1 passing through 2A.

Next, the operation of the above-described method for polishing the roll 1 for easily and efficiently imparting a uniform cross-polished stitch to the roll peripheral surface without polishing unevenness will be described below. In the method of polishing the roll 1 according to the present invention, as shown in FIG. 2, the roll 1 is polished by the grindstone 2 while applying a cross-polished stitch to the roll peripheral surface at the contact surfaces 3L and 3R between the grindstone 2 and the roll 1. ing. In FIG. 2, θ1 and θ2 indicate the direction of the outer peripheral velocity vector of the grindstone and the direction of the inner peripheral velocity vector of the grindstone at the contact surfaces 3L and 3R between the grindstone 2 and the roll 1, respectively. Reference numeral 1B indicates the rotation direction of the roll 1, and the circumferential direction of the roll 1 is parallel to 1B.

As shown in FIG. 2, the directions of the circumferential velocity vectors of the grindstone 2 on the contact surfaces 3L and 3R between the grindstone 2 and the roll 1 are inclined in directions opposite to each other with respect to the circumferential direction of the roll 1. That is, the direction of the peripheral velocity vector of the grindstone 2 between the outer peripheral edge and the inner peripheral edge of the one contact surface 3L is inclined upward and downward in the drawing, and the direction between the outer peripheral edge and the inner peripheral edge of the other contact portion 3R. The direction of the peripheral velocity vector of the grindstone 2 is inclined downward and to the right in the drawing.

Therefore, according to the roll polishing method of the present invention, the grindstone 2 is relatively moved at least once in the direction of the axis 1A of the roll 1 as shown in FIGS. 3 (a) to 3 (d). In addition, cross polishing stitches, which are intermittent polishing stitches inclined at θ ⁺ and θ ^{− in} directions opposite to each other with respect to the circumferential direction, can be provided on the roll peripheral surface.

In the method of polishing the roll 1 of the present invention, it is not necessary to apply the micro-vibration to the grindstone 2 in the direction of the axis 1A of the roll 1, and the grindstone 2 rotates, so that it is hard to cause clogging, and it is not necessary to frequently change the grindstone 2. This makes it possible to efficiently provide a uniform cross-polished surface without polishing unevenness to the roll peripheral surface. In the present invention, moving the grindstone 2 relatively means rotating the roll 1 and moving the rotating grindstone 2 in the direction of the axis 1A of the roll 1 or rotating the grindstone 2 and rotating the roll 1 It is to move in the direction of the axis 1A or to move both the roll 1 and the grindstone 2 in opposite directions. If the relative movement speed of the grindstone 2 is set sufficiently small with respect to the outer peripheral speed of the grindstone 2, the inclination angle of the cross-polishing marks theta ^+, theta ^- no significant effect on the.

According to the method of polishing the roll 1 of the present invention, if the relative movement speed of the grindstone 2 is set to a low speed, for example, about 1 mm / sec, a polishing defect called “hitting” does not occur.

(3) If a grindstone having a finite width is used and the roll is moved in the axial direction at a finite speed while the roll is polished at a finite grindstone rotation speed, the polishing lines are distributed in a range different from right to left in principle as shown in FIG. By increasing the number of rotations of the grindstone, the angle formed by the left and right polished stitches with respect to the circumferential direction approaches a state of being symmetrical as shown in FIG. 3B, but does not become strictly symmetrical. Also, by reducing the width of the grindstone from the state of FIG. 3D, the distribution of the polishing angle approaches the state where the distribution of the polishing angle becomes narrow, although the angle differs between the left and right as shown in FIG. 3C. , Not exactly parallel. Furthermore, by increasing the number of revolutions of the grindstone using a narrower grindstone, the angle approaches the state where the angle is bilaterally symmetric and the polishing lines are parallel, as shown in FIG. Not be.

In the present invention, in any of the embodiments, the polishing is performed at a finite grinding wheel rotation speed using a finite width grinding wheel, so that the polishing is performed in a state shown in FIG. 3D, and strictly, FIGS. 3A to 3C. However, it can be adjusted to a state close to that, and even in the state of FIG. 3D, a gloss improving effect can be sufficiently obtained while preventing uneven gloss.

The reason why the offset amount X of the grindstone 2 in the method for polishing the roll 1 of the present invention is set to be more than 0 and less than 1/2 of the outer diameter of the grindstone 2 is as follows. When the offset amount X of the grindstone 2 is set to 0, the direction of the circumferential velocity vector of the grindstone 2 on the contact surfaces 3L and 3R shown in FIG. The average value of the inclination angles is less than 5 °, and the effect of improving the gloss becomes insufficient. On the other hand, when the offset amount X of the grindstone 2 is set to の of the outer diameter of the grindstone 2, the direction of the circumferential velocity vector of the grindstone 2 on the contact surfaces 3L and 3R shown in FIG. This is because they are almost parallel, and the average value of the inclination angle of the polished eyes exceeds 85 °, the wear of the cross polished eyes is fast, and the gloss improving effect of the cross polished eyes cannot be maintained.

Note that the offset amount X is the distance between the axis 1A of the roll 1 and the axis 2A of the grindstone 2. In the roll polishing machine, the axis 2A of the grindstone 2 is made coincident with the normal 1N of the roll 1, and then the above description is made. As described above, it is general that the grindstone 2 is set to be shifted in parallel by the offset amount X.

In the above description, the whetstone 2 is relatively moved in the direction of the axis 1A of the roll 1 to give the cross-polished stitch to the peripheral surface of the flat roll, but in the present invention, FIG. In FIG. 4B, a cross-polishing line can be provided on the peripheral surface of the roll with a curve, which shows the change in the diameter in an enlarged manner.

When imparting a cross-polishing line to a roll with a curve according to the present invention, the grindstone 2 was attached to a roll grinder (not shown), the roll 1 was attached to the roll grinder, and the grindstone 2 was rotated while rotating. It is brought into contact with the roll 1 and relatively moved in the axial direction of the roll 1. At this time, as shown in FIGS. 4A and 4B, the offset amount X of the grindstone 2 is set to be more than 0 and less than 1/2 of the outer diameter of the grindstone 2, and the grindstone 2 is disposed on both sides of the dividing line 2D. And the roll 1 are brought into contact with each other, and the rotating shaft 2A of the grindstone 2 is inclined toward the moving direction with respect to the normal 1N of the roll 1 as shown in FIG. Therefore, if the grindstone 2 is relatively moved in the direction of the roll axis 1A while following the curve, it is possible to easily and efficiently impart a uniform cross-polished stitch to the roll peripheral surface.

FIGS. 4 (a) and 4 (b) show the contact state between the grindstone 2 and the roll 1 in the case where a cross-polished stitch is provided to a roll with a curve, and FIGS. The same components as those in (c) are denoted by the same reference numerals, and description thereof is omitted. FIG. 4B is a partial cross-sectional view taken along the line B′-B ′ in FIG.

The difference between the case where the cross abrasive is provided on the peripheral surface of the flat roll and the case where the cross abrasive is provided on the peripheral surface of the curved roll is that when the grindstone 2 is moved in the axis 1A direction of the roll 1, The axis of the grindstone 2 is held perpendicular to the axis 1A of the roll 1 so that the axis 2A of the grindstone 2 attached to the machine is parallel to the normal 1N of the roll 1; The angle between the axis 2A of the grindstone 2 and the axis 1A of the roll 1 is changed so that the axis 2A of the grindstone 2 attached to the polishing machine is parallel to the normal 1N of the roll 1 according to the roll curve. It is in.

By the way, in the polishing method of the roll 1 of the present invention, the rotation axis 2A of the grindstone 2 is inclined in the movement direction with respect to the normal 1N of the roll 1 by tilting the rotation axis 2A of the grindstone 2 in the movement direction. However, when the roll 1 is polished, the depth of the polished eye provided at the contact surface 3L in front of the moving direction 2C of the grindstone 2 becomes shallower than the depth of the polished eye provided at the contact surface 3R behind the moving direction 2C of the grindstone 2. Because I noticed that.

Therefore, in the polishing method of the roll 1 of the present invention, as shown in FIG. 5, the surface pressure of the contact surface 3L at the front of the moving direction 2C of the grindstone 2 is changed to the surface of the contact surface 3R at the rear of the moving direction 2C of the grindstone 2. The shaft 2A of the grindstone 2 is inclined in the direction of movement 2C by an angle α with respect to the normal 1N of the roll 1 so that the pressure becomes higher than the pressure, and the rear contact surface of the polishing eye provided by the front contact surface 3L. The depth after the surface is polished by the 3R and becomes shallow is substantially equal to the depth of the polished line provided on the rear contact surface 3R. As described above, when the rotating shaft 2A of the grindstone 2 is inclined toward the moving direction and the cross polishing is applied to the peripheral surface of the roll, the rotating shaft 2A of the grindstone 2 is not inclined in the moving direction, and the roll 1 is not inclined. Compared to the case of polishing, even if the pressure extension is made longer, the effect of improving the gloss by the cross-polished eyes can be maintained. FIG. 5 is a partial cross-sectional view showing a polishing state when the axis 2A of the grindstone is inclined, and passes through the axis 2A of the grindstone 2 in FIG. This is a state when viewed in a cross section parallel to and perpendicular to the paper surface. However, in FIGS. 2 and 4A, the axis 2A of the grindstone 2 is not shown, and the center O of the polished surface of the grindstone 2 is shown instead of the axis 2A of the grindstone 2. The grinding wheel shaft 2A passes through this O.

When the roll 1 is polished without inclining the rotation axis 2A of the grindstone 2 in the moving direction, the depth of the polished stitch provided on the contact surface 3L in front of the moving direction 2C of the grindstone 2 depends on the moving direction 2C of the grindstone 2. The reason why the depth is smaller than the polishing depth given by the rear contact surface 3R is that when the surface pressure at the contact surfaces 3L and 3R between the grindstone 2 and the roll 1 does not incline the rotating shaft 2A of the grindstone 2 in the movement direction, This is because, equally, the polished stitch provided on the contact surface 3L at the front in the moving direction 2C of the grindstone 2 is polished at the rear contact surface 3R.

The inclination angle α of the grinding wheel axis 2A with respect to the roll normal 1N is within a range in which the grinding wheel 2 can maintain contact at the contact surfaces 3L and 3R on both sides due to elastic deformation, and is provided at the contact surface 3L in front of the moving direction 2C of the grinding wheel 2. The depth of the polished eye after polishing on the rear contact surface 3R may be substantially equal to the depth of the polished eye provided on the rear contact surface 3R. The inclination angle α can be determined by the material of the rolling roll 1, the grain size of the grindstone, the material of the grindstone, and the like, and can be 0.01 to 0.5 °.

In these figures, the moving direction 2C of the grindstone 2 is set to the left direction, but may be set to the opposite right direction. In this case, the contact surface in front of the moving direction of the grindstone 2 becomes 3R, and the moving direction 2C of the moving direction of the grindstone 2 is changed. The contact surface at the rear is 3L. In these figures, the grindstone 2 is moved in the direction of 2C, but the roll 1 may be moved in the direction opposite to 2C.

In the above-described method for polishing the roll 1 of the present invention, the upper limit of the offset amount X of the grindstone 2 can be set to 1/2 of the inner diameter of the grindstone 2. By doing so, the uneven wear on the polished surface of the grindstone 2 which occurs when the upper limit of the offset amount X of the grindstone 2 is set to not less than 1/2 of the inner diameter of the grindstone 2 and less than 1/2 of the outer diameter is reduced. Can be suppressed.

FIGS. 6A and 6B show that the polished surface of the grindstone 2 in a range of not less than の of the inner diameter of the grindstone 2 and up to the offset amount X does not come into contact with the roll 1. This shows a state in which the wear of the metal became uneven. Under such a polishing condition that uneven wear occurs on the polished surface of the grindstone 2, when polishing a large-diameter roll having a large polished area, the truing of the grindstone 2 is performed for each predetermined polished area (deformation as shown in FIG. 6B). (The flattening of the grindstone surface that has been finished) and dressing (sharpening) are required, which lowers the polishing work efficiency and increases the polishing cost.

粒度 Further, it is desirable that the grain size of the abrasive grains of the grindstone 2 used in the above-described polishing method of the present invention be # 100 to # 400. The reason for this is that if the grain size of the abrasive grains of the grindstone 2 is less than # 100, the polishing grain applied to the roll becomes coarse, causing seizure and uneven gloss. Is more than # 400, the effect of smoothing the surface of the metal plate is reduced, and the effect of improving the gloss of the cross-polished eyes is reduced. For this reason, it is desirable that the grain size of the abrasive grains of the grindstone 2 used in the present invention is # 100 to # 400.

The grain size of abrasive grains of # 100 to # 400 is defined as the grain size of diamond and cubic boron nitride (also called CBN) abrasive grains (JIS B4130). 100/120 to 325/400 means that the particle size exceeding this range is too small to be suitable for giving a polishing grain to the roll surface, while the particle size below this range is too large. As a result, the polished eyes may be too sparse and the metal plate may not have sufficient gloss.

  The material of the abrasive grains of the grindstone 2 used in the present invention can also be diamond or CBN. In the case of giving a cross-polished grain to a steel roll, it is good to use CBN because it does not seize like diamond and a steel roll. Further, the binder for holding the abrasive grains and forming the abrasive grain layer portion can be resin or vitrified, and the concentration of the abrasive grains can be in the range of 50 to 200. When the concentration of the abrasive grains is set to 75 or 100, it is preferable because a polishing grain having a uniform depth can be given to the roll surface.

  The function of the roll provided with the cross-polished eyes in the above-described polishing method of the present invention will be described. Since the roll polished by the roll polishing method of the present invention is uniform without polishing unevenness, for the following reasons. It is considered that the metal plate can be rolled without meandering, and a high-gloss metal plate without uneven gloss can be obtained.

(1) Since the cross-polishing lines are inclined in the opposite direction to the longitudinal direction of rolling in the roll bite, the thrust force acting on the metal plate can be offset, and the metal plate can be rolled stably without meandering it can. (2) Since the cross-polishing line is inclined with respect to the longitudinal direction of the rolling, the polishing line is substantially parallel to the circumferential direction of the roll, and the polishing line is more polished than the case where the roll surface is a mirror surface. Since the metal plate has a large smoothing effect on the surface of the metal plate obtained by friction between the metal plate and the roll bite and the occurrence of micro defects can be suppressed, a high gloss metal plate can be obtained. (3) Rolling is performed with a roll provided with uniform cross-polished eyes without polishing unevenness, so that a metal plate without gloss unevenness can be obtained.

本 The present invention was applied as follows.

Example 1: Applying a cross-polishing line to the peripheral surface of a flat roll and applying it to a cold tandem rolling mill Example 2: Applying a cross-polishing line to the peripheral surface of a flat roll and applying it to a 12-stage cluster type rolling mill Example 3: Applying a cross-polished stitch to the peripheral surface of a curved roll and applying to a cold tandem rolling mill [Example 1]
Rolls for rolling incorporated in the first to fifth stands made of semi-high speed steel having a diameter of 600 mm are polished under the polishing conditions shown in Table 1, and then incorporated into a cold tandem rolling mill consisting of five stands as a pair of upper and lower, and hot-rolled.・ A SUS 430 ferritic stainless steel sheet with a thickness of 4.0 mm after annealing and pickling was rolled to a thickness of 1.5 mm. In addition to memorizing the total pressure extension after the rolls were incorporated into the cold tandem rolling mill, the obtained steel sheet was further subjected to annealing, pickling, and temper rolling, and the glossiness of the steel sheet at the above total pressure extension ( GS 20 °).

Table 1 shows the polishing conditions, the inclination angle of the polishing line, the roll roughness Ra after polishing (arithmetic mean roughness of JIS B 0601: hereinafter simply referred to as roughness), the presence or absence of unevenness of the roll after polishing, and the time of rolling. The presence or absence of meandering, the total pressure extension, and the gloss (GS 20 °) of the steel sheet at this total pressure extension are also shown.

The inclination angle of the polishing marks of rolls theta ^+, theta ^-, when the theta ⁺ is inclined to face the upper right from the lower left as shown in Figure 3, toward the upper left from the lower right a case where inclined manner theta ^- and then, is the angle formed between the circumferential direction. The same applies to the following examples. Roll roughness was measured in the axial direction of the roll. In the cold tandem rolling mill, the rolling speed was set to 200 mpm, and the rolling was performed while supplying a mineral rolling oil of 20 cSt (40 ° C.) in a 5% emulsion state.

Under the roll conditions A01 and A02, a CBN wheel (shape 6A2 of JIS B 4131) was used as a hollow disc-shaped grindstone, and the roll was polished by rotating the grindstone while contacting the roll. In this case, if the offset amount of the grinding stone is more than 0 and less than 1/2 of the outer diameter of the grinding stone, and the grinding stone is equally divided on the surface including the circumference of the roll, the contact surface between the grinding stone and the roll will be on both sides of the dividing line. The roll was brought into contact with the roll so as to be present in the roll, and was moved once (one way) in the axial direction of the roll to give a cross-polished stitch to the roll peripheral surface.

On the other hand, under the roll condition A09 of the comparative example, the offset amount of the grindstone was set to 0, and other conditions were the same as the rule condition A01. Under the roll condition A10 of the conventional example, a lapping film was used, and the lapping film was vibrated at 5 Hz in the axial direction of the roll to give a cross polishing stitch on the roll peripheral surface. Under the roll condition A11 of the conventional example, a flat grindstone was used, the moving speed of the grindstone was increased, and spiral polishing was provided on the roll peripheral surface. Further, in the roll condition A12 of the conventional example, a grindstone having the same grain size and shape as the roll condition A01 was used, and one end of the grindstone was brought into contact with the grindstone having only one inclined surface.

Comprehensive evaluation was performed as follows. No roll unevenness and meandering during rolling occurs, and 10 rolls can be provided with a cross-polished stitch without truing and dressing, and the gloss (GS 20 °) of the steel sheet exceeds 880 at a pressure extension of 10 km. In the case, ○, cross polishing can be given to 10 rolls without truing and dressing, and when the glossiness (GS 20 °) of the steel plate is more than 880 with a pressure extension of more than 10 km and 880 or more, Roll unevenness and meandering during rolling are not generated, and the glossiness is 880 or more at a pressure extension of 10 km, but the number of dressings is per roll, or the glossiness (GS 20 °) of the steel sheet is pressure extension It is assumed that the distance is more than 850 and less than 880 at 10 km. × indicates that the glossiness was less than 850, or that either the polishing unevenness of the roll or the meandering during rolling occurred.

From this result, in the case of the roll condition A02 in which the rotating shaft 2A of the grindstone 2 was inclined toward the moving direction using the hollow disc-shaped grindstone, polishing unevenness did not occur, and the roll was cold-rolled. In this case, the glossiness of the steel sheet was better than that of Comparative Example A09. Moreover, in the case of the roll condition A02 in which the rotating shaft 2A of the grindstone 2 is inclined toward the moving direction using a hollow disk-shaped grindstone, the roll under the roll condition A01 in which the grindstone axis is polished without being inclined in the moving direction. It can be seen that the life of the polished eyes is longer than that of the polished eyes, and the effect of improving the gloss of the cross-polished eyes can be maintained.

On the other hand, in the conventional example A10 in which a lapping film is used and the lapping film is vibrated in the axial direction of the roll to provide a cross-polishing line, and in the conventional example A11 in which a flat grinding wheel is used and a spiral polishing line is provided, In addition, polishing unevenness occurred, and gloss unevenness also occurred on the steel sheet, and the product was degraded. Further, in the conventional example A12 in which one end of the hollow disk-shaped grindstone was brought into contact and only one of the grindstones was provided with an inclined grinding line, meandering occurred during rolling, and the rolling had to be stopped.
[Example 2]
Rolls made of cold die steel with a diameter of 80 mm for polishing are polished under the polishing conditions shown in Table 2, and then incorporated in a 12-stage cluster type rolling mill as a pair of upper and lower parts. The material thickness after hot rolling, annealing and pickling A 3.0 mm SUS 304 austenitic stainless steel sheet was rolled to a thickness of 0.25 mm.

After storing the total pressure elongation after incorporating the rolls in the 12-stage cluster type rolling mill, the obtained steel sheet was further subjected to one pass of annealing, pickling, temper rolling, and buff polishing under the same conditions. The glossiness (GS 20 °) of the steel sheet at the total pressure extension was measured.

Table 2 shows the polishing conditions and the inclination angle of the polishing line, the roughness of the roll after polishing, the presence / absence of unevenness of the roll after polishing, the presence / absence of meandering at the time of rolling, the extension of the total pressure, and the glossiness of the steel sheet at the extension of the total pressure. (GS 20 °).

ロ ー ル Roll roughness was measured in the axial direction of the roll. In the 12-stage cluster type rolling mill, the rolling speed was set to 200 m / min, and the rolling was performed in 9 passes while supplying mineral oil having a viscosity of 3 cSt (40 ° C.) neat. In the invention examples B01 to B08, a CBN wheel (shape 6A2 of JIS B 4131) was used as a hollow disk-shaped grindstone. When the offset amount is more than 0 and less than 1/2 of the outer diameter of the grindstone, and the grindstone is equally divided on the surface including the circumference of the roll, the grindstone should be such that the contact surface between the grindstone and the roll exists on both sides of the bisector. Was brought into contact with the roll and moved once in the axial direction of the roll to give a cross-polished stitch to the roll peripheral surface.

ロ ー ル In the roll condition B09 of the comparative example, the offset amount of the grindstone was set to 0, and the other roll conditions were the same as B01, and polishing lines substantially parallel to the circumferential direction were provided. Under the roll condition A10 of the conventional example, a lapping film was used, and the lapping film was vibrated at 8.5 Hz in the axial direction of the roll to give a cross-polished stitch. In Conventional Example B11, a spiral grind was provided by using a flat grindstone, making the outer peripheral speed of the roll slower than the invention example, and increasing the moving speed of the grindstone. In Conventional Example A12, one end of a hollow disc-shaped grindstone was brought into contact, and a grindstone having the same grain size and shape as the roll condition A01 of Example 1 was provided with a polished grain inclined only on one side.

Comprehensive evaluation was performed as follows. No roll unevenness and no meandering during rolling, and the gloss of the steel sheet (GS 20 °) is 10 km for a pressure extension of 10 km. Is 850 if the length is more than 10 km and the table length is more than 919 and the back is 919 or more. △ is 10 km when the roll polishing unevenness and meandering during rolling do not occur and the glossiness (GS 20 °) of the steel sheet is 10 km. In this case, it is assumed that the value is not less than (front 800 / back 869) and less than (front 850 / back 919). × indicates that the gloss of the steel plate was less than (Table 800 / Back 869), or that either the polishing unevenness of the roll or the meandering during rolling occurred.

From this result, when using a hollow disc-shaped grindstone and polishing under the roll condition B02 in which the rotation axis 2A of the grindstone 2 is inclined toward the moving direction, polishing unevenness does not occur, and cold rolling is performed by this roll. When the test was performed, meandering did not occur during rolling, and it can be seen that the glossiness of the steel sheet was better than that of Comparative Example B09. In addition, in the case of the roll polished under the roll condition B02 which satisfies the polishing conditions of the present invention, the life of the polished eyes is longer than that of the roll polished under the roll condition B01 which is polished without inclining the axis of the grindstone in the moving direction, and the The gloss enhancement effect by the polished eyes can be maintained.

On the other hand, the conventional example B10 using a lapping film and vibrating the lapping film in the axial direction of the roll to give a cross-polishing line, and the conventional example B11 using a flat grindstone and giving a spiral polishing line, In addition, polishing unevenness occurred, and gloss unevenness also occurred on the steel sheet, and the product was degraded. Further, in the conventional example B12 in which one end of a hollow disc-shaped grindstone was brought into contact and only one of the grindstones was provided with an inclined polishing line, meandering occurred during rolling, and the rolling had to be stopped.
[Example 3]
Rolls of semi-high-speed steel rolls with a diameter of 600 mm to be installed from the first to the fifth stand are arranged in order from the upstream, and the curves are sequentially set as half-amplitude (phase 0 to π) sine curves of 200, 200, 100, 100, and 50 μm per radius. After polishing under the polishing conditions shown in FIG. 4, the curved rolls (diameter at the center of the body length was 600 mm) were assembled into each stand of a cold tandem rolling mill as a pair of upper and lower parts, and other conditions were the same as in Example 1. Rolling, while memorizing the total pressure elongation after incorporating the rolls in the cold tandem rolling mill, further annealing, pickling, temper rolling the resulting steel sheet, the steel sheet in the above total elongation pressure extension The gloss (GS 20 °) was measured.

Table 3 shows the polishing conditions and the inclination angle of the polishing line in the roll, the roll roughness after the polishing, the presence / absence of unevenness of the roll after the polishing, the presence / absence of meandering at the time of rolling, the total pressure extension, and the total pressure extension. The gloss (GS 20 °) of the steel sheet is also shown. The roll roughness was measured in the axial direction of the roll. In the cold tandem rolling mill, the rolling was performed while the rolling speed was set to 200 mpm and mineral rolling oil of 20 cSt (40 ° C.) was supplied in a 5% emulsion state.

The rolls to be incorporated into the first to fifth stands under the roll conditions D01 and D02 use a CBN wheel (shape 6A2 of JISB4131) as a hollow disc-shaped grindstone, form the above curve by rough polishing, and then give a cross-polished stitch. In doing so, as shown in FIGS. 4A and 4B, the axis of the grindstone 2 attached to the polishing machine (not shown) is parallel to the normal 1N of the roll 1 according to the roll curve. The angle between the axis of the grindstone 2 and the axis of the roll 1 is changed, the offset amount of the grindstone 2 is set to more than 0 and less than 1/2 of the outer diameter of the grindstone 2, and the grindstone 2 includes the circumference of the roll 1. When the surface was equally divided in the direction of the roll axis 1A, the grindstone 2 was brought into contact with the roll 1 so that the contact surface was present on both sides thereof, and was moved once in the axial direction of the roll 1.

In the roll condition D11 of the comparative example, the offset amount of the grindstone was set to 0 for the rolls incorporated in the first to fifth stands, and the other conditions were the same as D01. Granted. As the roll condition D12 of the conventional example, a cylindrical disc-shaped grindstone was used for the roll to be incorporated into the first to fifth stands, and the circumferential side face was pressed against the circumferential surface of the roll while being rotated, so that the roll was substantially fixed in the circumferential direction of the roll. A parallel polishing line was provided on the peripheral surface of the roll.

Comprehensive evaluation was the same as in Example 1.

From these results, when the hollow disc-shaped grindstone was used and polished under the roll condition D02 in which the rotating shaft 2A of the grindstone 2 was inclined toward the moving direction, the curved rolls of the first to fifth stands were used in Example 1. It was found that a cross-polished stitch having substantially the same inclination angle and roll roughness as A01 and A02 could be provided, and no polishing unevenness occurred. Further, in the case of the roll polished under the roll condition D02 that satisfies the polishing conditions of the present invention, the glossiness of the steel sheet is better than that of Comparative Example D11 and Conventional Example D12, and neither uneven gloss nor meandering occurs. Further, the roll polished under the roll condition D02 that satisfies the polishing conditions of the present invention has a longer polishing life than the roll under the roll condition B01 polished without inclining the axis of the grindstone in the moving direction, and the cross-polishing The effect of improving the gloss can be maintained.

FIG. 3 is a schematic explanatory view showing a polishing state when a flat roll is polished using a hollow disk-shaped grindstone without tilting the axis of the grindstone in a moving direction. It is a top view which shows the direction of the circumferential velocity vector of a grindstone in the contact surface of a grindstone and a roll at the time of giving a cross grinding | polishing item. It is a schematic development view of the surface of the roll which shows the inclination angle of the cross polishing eye provided by the roll polishing method of the present invention. It is the schematic which shows the contact state at the time of grinding a roll with a curve using a hollow disk-shaped grindstone, without inclining the axis | shaft of a grindstone in a movement direction. FIG. 3 is a partial cross-sectional view showing a polishing state in which a grinding wheel axis 2A is inclined. FIG. 6A is a schematic plan view showing the contact state between the polished surface of the grindstone and the roll when the offset amount of the grindstone 2 is equal to or more than 内径 of the inner diameter of the grindstone and less than 1/2 of the outer diameter of the grindstone. FIG. 6B is a front view showing a worn state of the grindstone after use in the contact state. FIG. 7A is a partial cross-sectional view illustrating a contact point between a polishing surface of a grindstone and a roll, and FIG. 7B is a diagram illustrating a contact point between a polishing surface of the grindstone and a roll. It is a schematic plan view showing a point. It is a schematic development view of the roll surface which shows the inclination of the roll grinding | polishing provided by the polishing method of the conventional example.

Explanation of reference numerals

1 Rolls for rolling (rolls)
1A Roll rotation axis (roll axis)
1B Roll rotation direction
1N Roll normal 2 Hollow disk-shaped whetstone (whetstone)
2A Grindstone axis (grindstone axis)
2B Wheel rotation direction 2C Wheel movement direction O Center of the grinding surface of the grinding wheel 2D Line passing through the center of the grinding surface of the grinding wheel and equally dividing the grinding wheel by a virtual surface including the circumference of the roll
3L, 3R Grinding stone grinding surface and roll contact surface
4L, the angle formed between the roll circumferential direction of the outer peripheral velocity vector and the inner peripheral velocity vector of the grinding wheel in the contact surface between the 4R grindstone and clearance X offset θ1 between the rolls, .theta.2 grindstone and the roll theta ^+, theta ^- Cross polishing marks of One tilt angle and the other tilt angle

Claims (1)

Using a hollow disk-shaped whetstone, contact the rolling roll rotated while rotating the whetstone, and further move relatively in the axial direction of the rolling roll to polish the rolling roll, When the offset amount is greater than 0 and less than 1/2 of the outer diameter of the grinding wheel, and the grinding wheel is equally divided on a surface including the circumference of the rolling roll, the contact surface between the grinding wheel and the rolling roll is the same. The grinding wheel is brought into contact with the roll for rolling so as to be present on both sides of the dividing line, and the rotation axis of the grinding wheel is adjusted so that the surface pressure of the contact surface in the front of the movement direction of the grinding wheel is behind the movement direction of the grinding wheel. A method for polishing a roll for rolling, characterized by inclining in the moving direction so as to be higher than the surface pressure of a contact surface.

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