JPH06246641A - Roll polishing tool and roll polishing method using this polishing tool - Google Patents

Abstract

PURPOSE:To decrease disorder of polishing mesh so as to prevent a flatness from worsening by specifying ratio of an external diameter to a radius directional width and a value of the external diameter, of a grinding wheel, in a polishing tool formed by fixing an annulus ring grinding wheel to the periphery of a disk-shaped or column- shaped supporter. CONSTITUTION:In this polishing tool, having a disk-shaped supporter 6 hollowed at the central part to provide a rotary shaft 4, an annulus ring grinding wheel 3 is fixed to the periphery of this supporter. This grinding wheel 3 has a fixed width (radial direction width), and in the case of tilting the polishing tool to perform polishing work, the grinding wheel is fixed to the peripheral part of the supporter 6 so as to come into point contact with a roll surface. When assumed D for external diameter of the grinding wheel 3, it is formed so that D/W is 25 or more further with the external diameter D 100mm or more. At the time of polishing a roll, a rotary shaft of the polishing tool is displaced from a normal of the roll, to further respectively rotate in a condition tilted relating to the normal of the roll, and further by polishing the roll while relatively moving both the roll and tool in the axial direction, a uniform mesh can be given to the roll surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing tool for polishing a roll used for cold rolling a metal plate and a method for polishing a roll using the polishing tool.

[0002]

2. Description of the Related Art In the rolling of a metal sheet, the irregularities on the surface of a work roll (hereinafter simply referred to as "roll") are transferred to the metal sheet. The surface is used by polishing. It is also possible to give a special polishing mark to the roll surface by devising a method of applying the grindstone portion of the polishing tool to the roll surface during this polishing operation.

The inventor of the present invention first invented a method of bringing one end of a disk-shaped grindstone into contact with a roll and polishing it, and stably providing a polishing grain in a direction that is deviated (tilted) from the circumferential direction of the roll. Applied for a patent (Japanese Patent Application No. 3-208247).

FIG. 2 is a diagram conceptually explaining the polishing method of the present invention for imparting a polishing grain inclined in the roll axis direction.

As shown in FIG. 2 (a) as an example, the rotation of a disk-shaped grindstone 3 having an outer diameter D (here, it is assumed that the entire polishing tool described later is composed of the grindstone). The axis 4 is tilted by an angle β with respect to the roll normal 5, and
As shown in (b), the rotating shaft 2 of the roll and the rotating shaft 4 of the grindstone 3 are arranged so as to be displaced so that the distance becomes X, and the roll surface and the grindstone are brought into contact with each other at a point A.

An enlarged view of the vector at the contact point A in this state is shown in FIG. 2 (c). As illustrated, the rotational speed vector of the grinding wheel and V _T, the roll axial direction relative moving velocity vector of the grinding V _F, the vector of the rotational speed of the rolls V _R
Then, a vector obtained by combining these is V ₀ , and by this, the inclination angle (angle between the circumferential direction of the roll and the polishing eye) θ
Will be attached to the roll surface. This θ can be expressed by the following formula. Note that α is sin ^-1 (2X /
It is the inclination angle of the grindstone rotation vector shown in D).

[0007]

[Equation 1]

Further, when the grindstone is tilted in the opposite direction in FIG. 2 (a), θ is calculated by the following equation. Furthermore when the rotational direction of the roll is reversed, the positive and negative V _R is reversed with expression.

[0009]

[Equation 2]

When the contact state at the contact point A is an ideal point contact, it is possible to form uniform polishing stitches with a uniform inclination angle θ on the roll surface. However, in reality, due to the abrasion of the grindstone during the polishing work, the contact portion between the roll and the grindstone becomes a surface as shown in FIG. In this case,
Since the magnitude of the rotational velocity vector V _T of the grindstone differs depending on the position of the contact portion A ′ in the plane, the magnitude of the combined vector V ₀ and the tilt angle θ change depending on the position. as a result,
The polishing pattern on the roll surface becomes uneven, resulting in a random polishing state as shown in FIG. 4 (a).

When rolling is performed with a roll having a polishing surface as shown in FIG. 4 (a), for example, the above-mentioned Japanese Patent Application No. 3-208247.
Not only the purpose of obtaining a metal plate with high gloss as in the invention of No. cannot be achieved, but also unevenness occurs in smoothing the surface of the rolled material due to unevenness of local polishing on the roll surface,
In addition, since the friction coefficient is partially different, the length of rolling elongation differs in the strip width direction, resulting in a product with poor flatness as shown in Fig. 4 (b).

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention, in polishing a roll used for cold rolling a metal plate or the like, to reduce the irregularity of the polishing grain due to the expansion of the contact surface between the roll and the grindstone. The object of the present invention is to provide a polishing tool in which the above-mentioned contact surface does not become excessive during a polishing operation, and to provide a method for polishing a roll using the polishing tool. .

[0013]

The gist of the present invention is the following (1) roll polishing tool and (2) roll polishing method.

(1) A polishing tool comprising a disk-shaped or columnar support having a central axis of rotation and an annular grindstone fixed to the outer periphery thereof, wherein the outer diameter D of the annular grindstone is: A roll polishing tool having a ratio (D / W) to the radial width W of 25 or more and an outer diameter D of 100 mm or more.

(2) The end of the annular grindstone and the roll are separated from each other by displacing the rotation axis of the roll-polishing tool of the above (1) from the normal line of the roll and / or tilting the rotary shaft as it is with respect to the normal line of the roll. While in contact, rotate the polishing tool and roll,
A method of polishing the roll by moving the polishing tool relatively in the axial direction of the roll.

FIG. 1 is a vertical sectional view showing some typical shapes of the polishing tool of the present invention. In these figures,
Reference numeral 6 denotes a support having a rotating shaft 4, which may be a disk shape (cup shape) having a depressed central portion as shown in (a) to (c), or a solid shape as shown in (d). It may be cylindrical. The height (thickness) H is not particularly limited.

An annular grindstone 3 is fixed to the support 4. This grindstone 3 has a constant width (radial width)
When the polishing tool is tilted as shown in FIG. 2 to perform a polishing operation, the support 6 has a point contact with the roll surface.
Fixed to the outer periphery of the.

[0018]

According to the present invention, in a disk-shaped or column-shaped polishing tool having an end portion, by adjusting the outer diameter of the grindstone and the ratio of the outer diameter of the grindstone to the grindstone width in the radial direction, It is based on the finding that the length and direction can be made uniform.

As shown in FIGS. 2 and 3, the contact between the roll and the grindstone is initially a point contact, but as the grinding time elapses, the grindstone wears and they come into surface contact. become. The rotation speed vector of the grindstone at this time is
As shown in FIG. 3, since the size differs depending on the position,
The direction and size of the polishing mesh represented by the composite vector V ₀ of the rotation speed vector of the roll, the rotation speed vector of the grindstone, and the movement speed vector of the grindstone in the roll axial direction are not uniform.

If polishing is continued in such a state, the polishing pattern becomes non-uniform and the polishing state shown in FIG. 4 (a) is obtained.

When the roll and the grindstone are in surface contact,
In order to reduce the amount of change in the magnitude of the rotational velocity vector of the grindstone at each position of the contact (that is, V _T1 −V _T3 in FIG. 3), it is desirable that the outer diameter of the grindstone be as large as possible. Further, if the width W of the grindstone portion is large, it is not preferable because when the grindstone wears and the contact area with the roll increases, the magnitude of the velocity vector also differs between the outer side and the inner side in the radial direction.

That is, in the roll polishing tool of the present invention, the ratio D / W of the outer diameter D of the grindstone to the width W of the grindstone in the radial direction is set to 25 or more for the above reason. The diameter of the grindstone must be 100 mm or more. The outer diameter D of the discoid grindstone is 100
If it is less than mm, abrasion is remarkable, and even if W is made small, it is difficult to make the polishing grain constant, and W at that time is less than 4 mm, which is not realistic.

FIG. 1 shows an example of the shape of the polishing tool of the present invention.
(a) is a polishing tool in which the entire bottom surface of the cup-shaped support 6 is the grindstone 3, and (b) and (c) are parts of the bottom of the cup-shaped support 6 (outer peripheral side). Has become a polishing tool,
(d) is a polishing tool in which the grindstone 3 is fixed to the outer periphery of the solid cylindrical support 6.

The support 6 is preferably one having excellent rigidity, and a metal material is suitable. Usually, since a polishing liquid is used when polishing a roll, it is preferable to use an Al material, an Al alloy material, a stainless steel material, or the like that is not easily corroded by the polishing liquid and is easy to handle.

As the material of the grindstone 3, particles or powder of diamond, cubic boron nitride, alumina, silicon carbide or the like can be used. As a method of fixing this to the support 6, any method such as a vitrified method of baking these particles or powder with soluble clay such as feldspar, a resinoid method of fixing with a synthetic resin, a silicate method of baking with sodium silicate, etc. A method may be used.

When roll polishing is performed using the polishing tool of the present invention, as shown in FIG.
The roll surface 2 of the roll and the rotation axis 4 of the polishing tool, or both as shown in Fig. 2 (b), so that the roll surface and the grindstone come into contact with each other at a point. To do. Then, rotate the polishing tool around its axis 4,
At the same time, the roll or / and the polishing tool are relatively moved in the axial direction of the roll to proceed with the polishing operation. In the roll polishing tool of the present invention, since the outer diameter of the circular grindstone is large and the width of the grindstone in the radial direction is small, the contact area does not become too large even if the grindstone wears and makes surface contact. Therefore, since it is possible to suppress the change in the rotational speed vector of the grindstone depending on the location to a minimum, it is possible to obtain uniform polishing.

At this time, the rotation shaft 4 of the grindstone is tilted with respect to the normal line of the roll, and the tilt angle β when each of them is in point contact
Is not particularly limited, but a small value of more than 0 ° and 10 ° or less, particularly 2 ° or less is preferable in consideration of wear and deformation of the grindstone during polishing and uniformity of the finished surface.

By using the polishing tool of the present invention, it is possible to impart stable polishing marks to the roll. On the other hand, during rolling, the roll and the metal plate cause relative slippage, so when rolling with a roll whose polishing grain is inclined with respect to the circumferential direction of the roll, the inclined polishing grain was transferred at the beginning of rolling. The surface of the metal plate is smoothed by crushing the polishing pits and oil pits generated during rolling.

Therefore, in the method of the present invention, if the rotation speed of the roll and the polishing tool and the moving speed of the polishing tool in the roll axial direction are determined so that the above-mentioned θ becomes 80 ° or more, the glossiness is excellent. A metal plate can be manufactured.

On the other hand, if this θ is less than 80 °, a force in the plate width direction may be generated on the metal plate during rolling. In such a case, the metal plate meanders during rolling, or the metal plate after rolling is twisted. From this point as well, θ is preferably set to 80 ° or more.

When polishing the surface of the roll, the contact state with the grindstone changes depending on the radius R (mm) of the roll to be polished.
That is, as the roll radius increases, the area of the contact portion increases.

At this time, if the outer diameter of the annular grindstone is small, the magnitude of the rotational speed vector of the grindstone at each contact point will be different.

In order to reduce the change in the rotational speed vector of the grindstone, it is preferable to reduce W / D and R / D. Therefore, in consideration of the radius of the roll, the diameter D (mm) of the annular grindstone and the grindstone width W in the radial direction.
It is preferable to use a grindstone whose (mm) satisfies the following formula.

0.1 ≧ (W · R) / D ² ... Hereinafter, the present invention will be described in more detail with reference to Examples.

[0035]

Example: Using a polishing tool of the same shape as shown in FIG. 1 (a) (dimensions of each part are shown in Table 1), a diameter of 450 mmφ
A roll of (R = 225 mm) was polished.

First, after arranging the rotation axis of the polishing tool so as to match the normal line of the roll, without separating the grindstone from the roll,
Moreover, the polishing tool was displaced by the distance X (mm) without tilting the rotation axis. Next, the rotation axis of the polishing tool was tilted by 1 ° so that the end of the grindstone came into point contact with the roll. While rotating the polishing tool and the roll in that state, the polishing tool was relatively moved in the axial direction of the roll to polish the surface of the roll. At this time, the rotation speeds of the roll and the polishing tool and the moving speed of the polishing tool were adjusted to give polishing marks substantially parallel to the roll axis (θ = 90 °).

Table 1 shows the outer diameter D (mm) of the ring-shaped grindstone, the width W (mm) of the grindstone, and the rotation speed and movement speed of the roll and the polishing tool at this time. The inclination angle α of the polishing tool is sin (2X / D)
In the grinding tool rotating vectors shown is an angle which is inclined with respect to the roll axis, the rotational speed of polishing tool V _T (m /
Min), the roll axis moving speed of the polishing tool is V _F (m / min),
And shows the rotational speed of the rolls in the V _R (m / min).

Next, using the roll thus obtained as a work roll, SUS 430 having a plate thickness of 3.2 mm and a plate width of 1000 mm was used.
Stainless steel sheet (hot rolled, pickled material, surface roughness Ra 2.5 μm)
Was rolled using a synthetic ester rolling oil (concentration 3% emulsion) having a viscosity of 35 cSt at 50 ° C. Table 2 shows the rolling conditions at that time.

The rolls obtained as shown in Table 3 were used for all passes, or only for the final 5 passes,
After observing the surface gloss of the rolled material and the shape of the rolled material after rolling,
The results are also shown in Table 3.

The polishing was performed in the same manner using a polishing tool having an outer diameter D of the grindstone and / or a ratio of the outer diameter D to the radial width W outside the range of the present invention. The result is shown as a comparative example.

The glossiness was evaluated by the specular glossiness (Gs45 °) at a measuring angle of 45 ° according to JIS method, and 450 or more was indicated as ◯, 400 or more as Δ, and less than 400 as ×. In addition, the twist, middle stretch, and ear wave of the steel sheet are shown as ◯ for no presence, Δ for slightly present, and markedly for x. Overall evaluation is ◎
In all other cases, the worst evaluation of each item was taken as the overall evaluation.

In the roll polished by using the polishing tool of the present invention, since the polishing marks on the surface are evenly provided in parallel to the roll axis, the metal plate rolled using the roll has a gloss and a steel plate shape. It turns out that both are excellent.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

[Table 3]

[0046]

EFFECTS OF THE INVENTION When a roll is polished using the polishing tool of the present invention, it is possible to impart uniform polishing to the surface of the roll.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a shape example of a roll polishing tool of the present invention.

FIG. 2 is a diagram illustrating a polishing method in which a roll polishing mesh is inclined in a roll axis direction.

3 is a diagram showing a shape of a contact surface when a grindstone is worn in the polishing method shown in FIG.

FIG. 4 (a) is a diagram for explaining a state in which the direction of the roll-grinding (roughness of roughness) is non-uniform, and FIG. 4 (b) shows the shape of the metal plate rolled by such a roll of polishing-grinding. It is a schematic diagram.

[Explanation of symbols]

1. Roll, 2. Roll axis, 3. Whetstone,
4. Grindstone rotation axis, 5. Roll normal, 6. Support.

Claims (2)

[Claims] 1. A polishing tool comprising a disk-shaped or columnar support having a center axis of rotation and an annular grindstone fixed to the outer periphery thereof, wherein the outer diameter D and the radius of the annular grindstone. The ratio (D / W) to the direction width W is 25 or more, and the outer diameter D is
Roll polishing tool characterized by being 100 mm or more. 2. The end of the annular grindstone and the roll are displaced by displacing the rotation axis of the roll-polishing tool according to claim 1 from the normal line of the roll, and / or inclining the rotary shaft as it is with respect to the normal line of the roll. A roll polishing method comprising rotating a polishing tool and a roll in a state of being in contact with each other, and relatively moving the polishing tool in an axial direction of the roll.