JPH0569004A - Method for spreading width of metallic sheet - Google Patents

Abstract

PURPOSE:To offer a means for spreading the width of metallic sheet that high spreading efficiency is maintained under high productivity at low cost and that local ununiformity in thickness distribution is not generated after spreading work. CONSTITUTION:The metallic sheet or strip metal 2 is formed into a corrugated metal sheet with a rolling mill with a pair of upper and lower grooved rolls 4a, 4b which are smooth and of which the wave height is low in the middle part in the width direction and high in end parts and, successively, by executing work for spreading the wave of the corrugated metallic sheet or strip metal 2, the metallic sheet 2 where the local ununiformily in thickness distribution is not generated after spreading work can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for expanding the width of a metal plate or metal strip.

[0002]

2. Description of the Related Art As a means for widening the width of a long metal plate, as disclosed in, for example, Japanese Patent Publication No. 50-1463, a pair having a concavo-convex shape such as a sine wave in the roll axis direction as shown in FIG. There is known a method of forming a long metal plate material 2 into a corrugated plate material by means of the hole-shaped rolls 1a and 1b and then rolling the corrugated plate material by means of flat rolls 3a and 3b as shown in FIG.

In this prior art, when the corrugation is performed without applying the plate thickness reduction during the corrugation, FIG.
As shown in (a), in each of the convex portions of the hole-shaped rolls 1a and 1b, a restraining force R is generated against the material flow in the width direction of the plate material 2 which is relatively generated toward the central portion in the width direction. As a result, in the widthwise central portion of the plate material, a tension T sufficient to balance with the integrated force of the restraining force R received from the hole-shaped roll convex portion on the end side.
Is generated and the bending force P acts, the corrugated plate material greatly reduces the plate thickness at the roll convex portion. Therefore, the sheet thickness distribution of the formed corrugated sheet material locally has a large nonuniformity. Next, when the corrugated plate material is subjected to the spreading process, the locally large unevenness of the plate thickness distribution generated during the corrugating process remains after the process as shown in FIG. 9A. was there.

Further, in order to prevent the uneven distribution of the local plate thickness from occurring, it is necessary to increase the rolling reduction ((inlet plate thickness-exit plate thickness) / inlet plate thickness) during corrugation processing. ,
In this case, there is a problem that the rolling load becomes large, the equipment becomes large, and the cost becomes high.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above problems in the prior art, maintains a high width widening efficiency at a low cost with a high productivity, and a plate thickness distribution after machining. An object of the present invention is to provide a means for widening the width of a metal plate that does not cause local nonuniformity.

[0006]

In order to achieve the above object, the gist of the present invention is that a metal plate or a metal strip is smooth and has a low wave height at the center in the width direction and a high wave height at the ends. A method for widening a metal plate, which comprises forming a corrugated plate material by a rolling machine having a pair of upper and lower hole-shaped rolls, and then performing the wave widening process of the corrugated metal plate or the metal strip. is there.

[0007]

The present invention will be described in detail below.

First, the inventors of the present invention have, in order to obtain the above-mentioned locally nonuniform characteristics of the plate thickness distribution, have corrugations such as a sine wave in the roll axis direction and a wave height in the width direction during corrugation processing. After performing corrugation processing without applying plate thickness reduction, a corrugated plate material was subjected to corrugation spread processing using a roll having a uniform thickness. As a result, as shown in FIGS. 9 (a) and 9 (b), the non-uniformity of the local plate thickness distribution is large especially in the central part in the plate width direction, becomes smaller toward the end part, and the wave height becomes smaller. It was found that the lower the value, the smaller the nonuniformity of the local plate thickness distribution (see FIG. 7B). These phenomena are explained as follows. In the center portion in the width direction during corrugation, as shown in FIG. 8 (b), the tension T increases because the region in which the above-mentioned constraint force R is integrated is long. On the other hand, at the widthwise end portion, as shown in FIG. 8C, the region in which the restraining force R is integrated is short, so the tension T is much smaller than that in the widthwise central portion, and it is difficult to reduce the plate thickness. Become. Further, when the wave height is low, the bending force P at each convex portion of the hole-shaped roll is also reduced, and the restraining force R evaluated by multiplying the processing force P by the friction coefficient is also small. It is reduced and it becomes difficult for the thickness of the convex portion to be reduced. That is, it can be seen that during corrugation processing, local unevenness of the sheet thickness distribution is essentially likely to occur at the widthwise central portion and is unlikely to occur at the edge portions.

According to the present invention, when corrugating the material 2 such as a metal plate, the hole-shaped rolls 4a and 4b as shown in FIG. 1 are used.
Is used, the convex portion 5 of the hole-shaped rolls 4a and 4b is essentially formed in the central portion of the plate, which is likely to cause local unevenness of the plate thickness distribution.
Since the wave height is low, the tension T in the width direction and the bending force P inside the material are small, and the plate thickness distribution is almost uniform.
In addition, by increasing the wave height at the edge of the plate where local unevenness of the plate thickness distribution is unlikely to occur, the width expansion ratio of the corrugated plate material after the wave expansion process ([(plate after wave expansion process (Width-width of original plate) / width of original plate], it is possible to maintain the total arc length in the cross section in the width direction of the corrugated plate material. Further, according to the present invention, it is not necessary to reduce the plate thickness at the time of corrugating, so that the load becomes very small.

On the other hand, in the present invention, when the plate material is formed into a corrugated plate material, a forging machine having a pair of upper and lower dies which is smooth and has a low wave height at the center in the width direction and a high wave height at the ends may be used. it can. Further, in order to adjust the widening amount with respect to the plate material, it is possible to adjust the die or roll interval.

As a method of expanding and corrugating a corrugated plate material, for example, as proposed in Japanese Patent Application No. 2-57630, it is performed by dividing the corrugated plate material in the width direction with time (FIG. 2). (See (a), (b), (c)) It is possible to obtain a large amount of widening with a small local nonuniformity of the plate thickness distribution after the widening process.

[0012]

EXAMPLE As shown in FIG. 4, plate thickness: 30 mm, width: 100
The 0 mm plate material 2 is corrugated by a rolling machine having a hole-shaped roll (roll interval: 30 mm, wave height: 60 mm to 140 mm, wave pitch: 250 mm), and then the formed corrugated plate material is shown in FIG. Using a forging machine having a shape upper die 6 (lower die is flat) (die gap: 30 mm), the corrugated plate material was subjected to wave spreading and forging from the central part in the plate width direction to the end part gradually. As a result, as shown in FIG. 3, the maximum local nonuniformity of the plate thickness distribution after forging was about 0.1 mm, and a plate material having a width expansion ratio of about 20% could be obtained.

On the other hand, corrugation was performed using a hole-shaped roll having a uniform wave height in the width direction (roll interval: 30 mm, wave height: 100 mm, wave pitch: 250 mm) to spread the wave. In this case, a local plate thickness unevenness of about 1.0 mm occurs, and according to the present invention, the local plate thickness unevenness is 1
It can be reduced to about / 10.

[0014]

According to the present invention, it is possible to provide a means for ensuring a sufficient amount of widening at a practical cost and preventing local unevenness in the plate thickness distribution. Further, by combining the present invention with a continuous casting process in which it is difficult to change the plate width, it is possible to efficiently obtain a product having a wide plate width dimension and no local unevenness in the plate thickness distribution.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a roll hole shape used when carrying out the present invention.

FIG. 2 is a diagram showing an embodiment of a wave spreading process performed on the corrugated plate formed in FIG.

FIG. 3 is a diagram showing a plate thickness distribution of a flat plate material after carrying out the present invention.

FIG. 4 is a view showing a cross-sectional shape in the width direction of a corrugated hole-shaped roll used in an example of the present invention.

FIG. 5 is a view showing an example of the shape of a forging die used when the corrugated plate material is subjected to wave spreading processing.

FIG. 6 is a view showing a conventional technique for processing a raw plate into a corrugated plate material.

FIG. 7 is a diagram showing a conventional technique for performing wave spreading processing on a corrugated plate material.

FIG. 8 is a view showing problems and a mechanism thereof when molding a corrugated plate material according to a conventional technique.

FIG. 9 is a view showing a plate thickness distribution of a plate material after a corrugated plate material is formed by a conventional technique and subjected to a widening process.

[Explanation of symbols]

 1a, 1b Roll 2 Metal plate (material) 3a, 3b Flat roll 4a, 4b Pore roll 5 Convex part 6 Dice

Claims (1)

[Claims] 1. A corrugated plate material is formed by a rolling machine having a pair of upper and lower hole-shaped rolls that are smooth and have a low wave height at the center in the width direction and a high wave height at the ends. A method for widening the width of a metal plate, which comprises performing the widening process of the corrugated metal plate or the wave of the metal strip.