JP2575982B2 - Method for imparting gloss to metal plate surface - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for simultaneously controlling the surface gloss and the shape of a metal plate during cold rolling of the metal plate.

[0002]

2. Description of the Related Art Conventionally, as one of cold rolling of metal sheets, a rolling method using a cross roll rolling mill has been known. In this rolling method, a pair of work rolls for rolling are arranged so as to be alternately tilted in the opposite direction to intersect with a direction orthogonal to a feed direction of a metal plate as a rolled material, and these work rolls are used. Rolling was performed by rolling down the plate.

[0003] In rolling a metal plate by such a rolling method, not only the shape of the plate but also the glossiness of the surface of the metal plate is regarded as important as a part of quality. As a method of improving the surface gloss, there is a method of controlling a speed ratio fs between a plate speed after rolling and a work roll rotation speed to a predetermined range in accordance with a cross roll angle which is a cross angle of a work roll. Has been adopted.

[0004]

In the conventional control method as described above, when the value of the speed ratio fs deviates from a predetermined range due to disturbance of the rolling conditions and the surface gloss of the metal plate does not reach the target value, Control is performed to change the cross angle so that the gloss is improved. However, the change of the cross angle inevitably leads to the deterioration of the shape of the metal plate. Therefore, the technique according to the conventional method has a problem that both the surface gloss and the shape of the metal plate may not be satisfied at the same time.

[0005]

According to the present invention, there is provided a method for imparting gloss to a surface of a metal plate according to the present invention, wherein a strip-shaped metal plate is sandwiched between a pair of mutually intersecting work rolls while cold rolling is performed. In a method for imparting gloss to a metal plate surface by changing an intersection angle to improve the gloss of the surface of the metal plate, a shape control actuator may be used to determine the shape of the metal plate based on the plate shape of the metal plate after changing the intersection angle. Is characterized in that the plate shape is modified.

[0006]

The work roll is rotated while the strip-shaped metal plate is sandwiched between the pair of work rolls, so that the metal plate is cold-rolled and gloss is given to the surface of the metal plate.

At this time, when the gloss of the metal plate surface is reduced due to disturbance or the like, the crossing angle between the cross rolls is changed to improve the gloss, and a change in the plate shape accompanying this is fed back to the shape control actuator. Modify the plate shape.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 7 show a rolling device and the like used in a method for imparting gloss to a metal plate surface according to an embodiment of the present invention, and the present embodiment will be described with reference to these drawings.

FIG. 1 is a schematic configuration diagram of a control system according to an embodiment, FIG. 2 is a side view showing a main part of a cross roll rolling mill to which the embodiment is applied, and FIG. It is a front view showing an important section of a cross roll rolling mill to which an example is applied.

As shown in these figures, each motor 5
1 rotates the respective shafts 35 via the bevel gears 34 and rotates the screw shafts 32 screwed to the nuts 33 via the respective worm reducers 31, whereby the upper cross-fitted on the guide 36 is rotated. The head 29 and the lower cross head 30 are moved in directions opposite to each other in the direction of the pass line. By moving the upper and lower crossheads 29 and 30, the upper work roll chock 25 and the upper backup roll chock 27 and the lower work roll chock 26 are moved.
The lower backup roll chock 28 rotates in opposite directions about the center of the upper and lower work rolls 2a and 2b in the roll axis direction, and is used to rotate the upper work roll 2a and the upper backup roll 23, and the lower work roll 2b and the lower work roll 2b. The lower backup roll 24 is crossed.

During rolling, the plate shape of the rolled material S is adjusted by adjusting the cross angle and adjusting the hydraulic pressure of the work roll bender cylinder 7 of the upper and lower work rolls 2a and 2b.

That is, the upper and lower work rolls 2a and 2b sandwiching the rolled material S have rotation axes extending in a plane parallel to a plane formed by the surface of the rolled material S, and these axes are formed by the rolled material S From the direction perpendicular to the rolling direction of the rolling direction. Also,
The angle θ can be changed even during rolling by rotation of the screw shaft 32 accompanying rotation of the motor 51 as described above.

On the other hand, as shown in FIG.
From the rolled material S after being rolled by a and 2b, the glossiness is measured and detected by the glossiness measuring device 3, and
The plate shape is measured by the shape detector 4. Then, the measured value of the glossiness is sent to a work roll bender control panel 6 for controlling the operation of the work roll bender cylinder 7, and the measured value of the plate shape is changed to a cross angle adjusting device 5 for changing the cross angle.
Sent to

Therefore, when the glossiness of the rolled material S deviates from the target value, the cross angle adjusting device 5 for driving and rotating the motor 51 is rotated.
Changes the cross angle. The signal from the glossiness measuring device 3 is sent to the work roll bender control panel 6 via the cross angle adjusting device 5. Therefore, the work roll bender control panel 6 controls the hydraulic pressure of the work roll bender cylinder 7 based on the signal input from the glossiness measuring device 3 together with the signal input from the shape detector 4.

Here, the relationship between the cross angle, which is the intersection angle between the pair of work rolls 2a and 2b, and the gap between the rolls, and the relationship between the surface gloss of the rolled material S and the plate shape will be described.

That is, a pair of upper and lower work rolls 2a,
2b are crossed with each other to form a rolled material S which is a strip-shaped metal plate.
Adjustment of the cross angle in the rolling method of rolling the steel sheet affects not only the gloss of the metal plate surface but also the plate shape. The reason for this is that when a pair of work rolls 2a and 2b cross each other, the gap between the two work rolls 2a and 2b changes in the roll axis direction, and the gap between the center of the work rolls 2a and 2b in the width direction increases the initial set value. This is because the gap becomes larger than the gap (gap between the work rolls when the roll axis is parallel), and the gap distribution becomes almost parabolic.

Accordingly, the work rolls 2a and 2b are inclined at an angle θ in directions opposite to each other with respect to a direction orthogonal to the rolling direction, and the intersection angle between the upper and lower work rolls 2a and 2b is set to an angle 2θ.
Assuming that the gap distribution at the time of crossing is equivalent to making the surface of the work roll convex in the width direction, the shape of the surface of the work roll determines the convex amount δ of the rolled material S as follows. (1)

Δ = (y tan θ)^Two/ (Dw + S₀(1) where y is the distance from the center in the roll width direction, and Dw is
Work roll diameter, S ₀Is between the rolls at the center of the roll
Represents each interval. Therefore, in equation (1), the point at the distance y
The value of the convexity δ in this case is determined.

Here, a pair of upper and lower work rolls 2a, 2b
Are crossed with each other, in the rolling deformation region, shear deformation occurs in the width direction of the rolled material S on the surface of the rolled material S, and this effect is left on the surface of the rolled material S after rolling, so that the surface gloss of the rolled metal plate is reduced. Can be improved. Therefore, in order to sufficiently exhibit this effect, the speed ratio f, which is the ratio between the plate speed after rolling and the work roll rotation speed, is used.
The _s, it is necessary to control the range that is determined depending on the cross angle, the rolling operating conditions, the value of the speed ratio f _s may sometimes outside the above target range. At this time, it is necessary to change the cross angle in order to keep the surface gloss at the target value. However, if the cross angle is changed, the gap between the work rolls changes, and the plate shape deteriorates.

[0020] If you do not change the value of here at a speed ratio f _s,
It is indispensable to change the cross angle to control the surface gloss of the plate, but shape control actuators for controlling the plate shape include, for example, bending of a work roll, shift of a work roll or an intermediate roll, and a crown. There is a backup roll that can be changed (for example, a VC roll, a TP roll, a sleeve roll, and the like).

Therefore, the plate shape which deteriorates when the crossing angle between the work rolls is changed in order to obtain the required gloss is measured by measuring the plate shape and causing the work roll bender cylinder 7 which is one of the shape control actuators. The feedback can improve the quality.

The change in gloss and plate shape when the cross angle is changed will be described below with reference to FIGS. Here, FIG. 4 shows a graph representing the relationship between the cross angle θc and the gloss Gs of the plate, and FIG. 5 shows a graph representing the relationship between the cross angle θc and the plate shape under the same rolling conditions as FIG.
FIG. 6 shows a method of measuring a plate shape.

That is, as shown in FIG. 6, the steepness λ of the plate representing the plate shape of the rolled material S is λ = δ / L using the height δ and the pitch L of the wave generated in the rolled material S. expressed. The value of the steepness when a wave is present at the edge of the plate is set to + λ, and FIG.
, And is defined as edge elongation, and the value of steepness when a wave is present at the center of the plate is shown as −λ in FIG. 5 and is defined as middle elongation.

As shown in these figures, when the cross angle is increased, the glossiness increases, and the plate shape tends to change from edge extension to medium extension. And in FIG.
The plate shape when the work roll bender force is changed is also shown. It is understood that when the work roll bender force is increased, the plate shape tends to change to medium elongation.

From the above facts, the operation and operation of the method according to this embodiment are as follows. That is, the glossiness of the rolled material S is measured by the glossiness measuring device 3. For example, when the measured glossiness is smaller than the target value, the cross angle adjusting device 5 changes the cross angle so as to increase the cross angle. Will be As a result, the shape of the plate may change in the middle elongation direction. However, when the shape is measured by the shape detector 4 and the middle elongation exceeds the allowable limit, the work roll bender force is controlled by the work roll bender control panel 6. The hydraulic pressure of the cylinder 7 for the work roll bender is reduced so as to reduce the pressure.

Next, the specific operation and operation of this embodiment will be described with reference to the control flow of FIG.

First, when rolling is started, step S1 is executed.
, The rolling conditions such as the rotation speed of the work roll are read into the cross angle adjusting device 5, the cross angle and the bend angle are set in step S2, and the glossiness measuring device 3 is set in step S3.
Measurement of the glossiness of the rolled material S is performed. Further, in step S4, it is determined by the cross angle adjusting device 5 whether the glossiness is within a predetermined target value, and if so, rolling is continued and the process returns to step S3. On the other hand, if the gloss is not within the target value, the cross angle is changed in step S5.

Thereafter, in step S6, the shape of the plate is measured by the shape detector 4 or the amount of change in the plate shape is predicted by the cross angle adjusting device 5. Then, in step S7,
It is determined by the cross angle adjusting device 5 whether or not the plate shape is within a predetermined target value, and if so, rolling is continued and the process returns to step S3. On the other hand, if the plate shape is not within the target value, the process proceeds to step S8, and the process proceeds to step S8.
Then, the work roll bender control panel 6 operates the work roll bender cylinder 7 to adjust the plate shape, and returns to step S6.

From the above, it is possible to improve the glossiness while maintaining the plate shape of the rolled material S.

[0030]

According to the method for imparting gloss to the surface of a metal plate according to the present invention, when a metal plate is sandwiched between a pair of work rolls and cold-rolled, the metal plate is changed by changing the crossing angle between the work rolls. As a result of correcting the shape with a shape control actuator, the surface gloss and the plate shape can be simultaneously controlled to satisfy the target values, and high-quality metal sheet products can be produced by rolling.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a control system to which an embodiment of the present invention is applied.

FIG. 2 is a side view showing a main part of a cross roll rolling mill to which an embodiment of the present invention is applied.

FIG. 3 is a front view showing a main part of a cross roll rolling mill to which one embodiment of the present invention is applied.

FIG. 4 is a graph showing a relationship between a cross angle and a glossiness of a plate.

FIG. 5 is a graph showing a relationship between a cross angle and a plate shape under the same rolling conditions as in FIG. 4;

FIG. 6 is a view showing a method for measuring the shape of a rolled material.

FIG. 7 is a control flow according to an embodiment of the present invention, showing a flow for controlling glossiness and plate shape by operating a cross angle and a work roll bend force.

[Explanation of symbols]

 2a, 2b Work roll 3 Gloss meter 4 Shape detector 5 Cross angle adjuster 6 Work roll bender control panel 7 Work roll bender cylinder S Rolled material

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kanji Hayashi 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture Mitsubishi Heavy Industries, Ltd. Hiroshima Works (72) Inventor Toru Kaneko Kajima-cho, Kashima-gun, Ibaraki 3 Address: Kashima Works, Sumitomo Metal Industries Co., Ltd. (72) Shunji Kamada, Kajima-cho, Kashima-gun, Ibaraki 3rd floor, Kashima-cho, Sumitomo Metal Industries, Ltd. Kashima Works, Sumitomo Metal Industries, Ltd. No. 5-33 Sumitomo Metal Industries, Ltd. Research and Development Headquarters (56) References JP-A-4-71701 (JP, A) JP-B 52-19820 (JP, B2)

Claims (1)

(57) [Claims] 1. A metal which changes the crossing angle between work rolls while cold rolling with a strip-shaped metal plate sandwiched between a pair of mutually intersecting work rolls to improve the gloss of the surface of the metal plate. In the method for imparting gloss to a plate surface, based on the plate shape of the metal plate after the change of the intersection angle, correcting the plate shape of the metal plate with a shape control actuator, wherein the gloss of the metal plate surface is modified. Assignment method.