KR850002645Y1 - Preventing oscillation of a moving web - Google Patents

Abstract

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Description

Anti-vibration device of strip steel

1 is a perspective view of a continuous galvanizing device having a magnetic device according to the present invention.

2 is a circuit diagram of the present invention.

3 is an enlarged cross-sectional view of the magnetic device of FIG.

4 is a sectional view taken along the line IV-IV of FIG.

5 is a graph showing the amplitude test results of the band steel with and without the magnetic device of the present invention.

6 (a) and 6 (b) are diagrams showing the test results of the amplitudes with and without the magnetic device, respectively.

7 is a graph showing the relationship between the spacing between the band steel and the magnetic device and the magnetic force.

8 is a side view of another form of the present invention.

9 is a view showing another form of the magnetic device of the present invention.

The present invention provides a device for preventing vibration of magnetic strip steel that is continuously processed while the strip steel moves through various process lines such as continuous galvanizing line, annealing line, pickling line and inspection line. It is about.

When the steel strip is moving at a high linear velocity in this fixed line, various treatments and inspections of the steel strip are usually performed. For example, in a continuous zinc plating line, the thickness control of the material to be plated on the strip is made while the strip is moving at a speed of 200 m / min or more. In addition, the flow or thickness of the strip shall be detected while the strip is in motion.

In general, the band steel in motion is supported by a pair of rollers or pinch rollers with a tensile force acting in the direction of movement, so that the band steel between adjacent rollers vibrates in the thickness direction and width direction of the band steel. Various problems arise, such as the surface of a strip steel becoming concave or convex. These problems are aggravated when the linear velocity of the steel strip increases, and the quality of the steel strip is degraded due to scratch inspection, thickness detection error, and inaccuracy of the steel strip.

The present invention has been made in view of this point, and an object of the present invention is to provide an apparatus for preventing vibration and deformation occurring in the steel strip while it is moving.

In order to achieve the above object, the present invention is a device having a magnetic force generating device disposed along a traveling path in which a strip of magnetic material continuously moves, and the magnetic force generating device is spaced apart from both ends of the plate width end of the strip steel in the plate width direction, respectively. At the same time, the magnetic force generating device is arranged so as to be positioned on an extension line in the plate width direction passing through the cross section of the strip steel, and to detect the position of the plate width end portion of the strip steel again based on a detection signal from the detection apparatus. It is characterized by installing a moving device for adjusting the distance between the magnetic force generating device and the plate width end of the strip steel by moving it in the plate width direction of the strip steel.

Therefore, according to the present invention, by applying a magnetic field in the width direction of the strip steel in motion, the edge of the strip steel is pulled in the direction in which the magnetic field acts, and a tensile force is generated in the width direction of the strip steel to reduce the amplitude of the band steel vibration. Straighten the bend of the band steel.

In addition, the present invention uses the magnetic device in the continuous plating apparatus to prevent the vibration of the strip steel to suppress the vibration of the strip steel to effectively uniform the thickness of the plating material, as well as effectively prevent the bending phenomenon occurring on the plated surface of the strip steel. Can be. In addition, such a magnetic device can be used to prevent the vibration and bending of the band steel different from the continuous plating device such as the continuous inspection line.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 shows a form of the present invention in which a magnetic apparatus, which has been referred to as a reverse vibrating magnet, is used in a continuous galvanizing apparatus having a gas wiping nozzle. The upper roller 32, zinc for continuously supplying the lower roller 14, the pair of deflection rollers 16, 18, and the band steel 10 to the zinc-dissolved solution tank 12 in this galvanizing apparatus. There is a pair of gas wiping nozzles 20, 22 disposed on the surface of the dissolved application tank 12 and which rubs the plated strip steel 10 to eject gas for emitting light. The plating thickness of the strip steel in this galvanizing apparatus is on both sides of the strip steel from wiping nozzles 20 and 22 installed on the surface of the solution bath 12 when it is recovered from the solution bath 12 in which zinc is dissolved. It is controlled by the blowing of gas. The thickness is usually adjusted by varying the distance between the nozzle 20 in front and the nozzle 22 in the rear, the pressure of the blowing gas, and the speed of movement of the strip cavity.

The wiping nozzles 20 and 22 are supported to be slid by the pillars 28. The distance between the strip steel 10 and the wiping nozzles 20 and 22 is adjusted by the control motor 30. By operating the control motor 30, the wiping nozzles 20, 22 can be moved horizontally a little further or closer to the front and back surfaces of the strip steel 1. The wiping gas flows into the wiping nozzles 20 and 22 from the pipes 24 and 26, respectively.

After being recovered from the zinc solution bath 12, the strip steel 10 cannot be supported by any direct contact method until the plating material is cooled and solidified. Therefore, the position of the upper roller 32 must be high in proportion to the moving speed of the steel strip. In practice, an allowable height of about 40m is required at a moving speed of 200m / min. Since the increase in the allowable distance and the increase in the moving speed cause vibration and deformation of the strip steel 10, the distance between the wiping nozzles 20, 22 and the strip steel must be continuously controlled or kept larger. For example, the band steel 10 vibrates in a transverse plane having an amplitude of 3 mm to 10 mm at a frequency of 1 to 7 Hz. The dynamic pressure of the gas blown out from the nozzles 20 and 22 is changed by the transverse vibration of the strip steel. The thickness of the plated material plated on the strip steel 10 decreases as the distance decreases and increases as the distance increases. Therefore, the thickness of the plating layer becomes nonuniform.

For this reason, there has been an increasing demand for a zinc plating apparatus capable of uniformly plating layers at high linear velocities, and although it has been proposed to reduce the thickness of plating layers by increasing the pressure of the wiping gas, the pressure is only 0.6 kg / There was no choice but to increase to about 2 cm 2. Because the noise is increased by the gas pressure. In the embodiment of the present invention, there are four reverse vibrating magnets 34, 36, 38, and 40 near the near edge of the steel strip. The edge of the strip steel vibrating by the magnetic force of the magnet body is attracted to an area of higher magnetic flux density to prevent the strip steel from vibrating. The magnet bodies 38 and 40 are strongly supported by the side plate 42, and the magnet bodies 34 and 36 are strongly supported by another side plate located near the edge of the strip steel.

Moreover, in order to stabilize the strip steel, it is necessary to maintain a constant small gap between the magnet body and the edge of the strip steel. In practice, it is unavoidable to wind the band steel or to change the width of the band steel. For the same reason as above, the side plate 42 is supported to slide on the column 50 together with the threaded rod 44 connected to the control motor 48 by a belt. The side plate 42 can be moved horizontally slightly away from or close to the edge of the steel strip by actuating the control motor 48 to achieve the desired spacing between the magnets 38 and 40 and the corresponding edge of the steel strip. Can be.

The magnet bodies 34 and 36 can also move in the width direction of the strip steel in order to obtain the required spacing between the magnet bodies 34 and 36 and the corresponding edge faces of the strip steel.

In the embodiment of the present invention, four magnet bodies 34, 36, 38, and 40 are used to prevent the vibration of the strip steel, but the number of the magnet bodies is not limited to the embodiment of the present invention. For example, only the upper magnet bodies 34, 38 can be used. Also, if circumstances permit, only one magnet, for example the magnet body 34, can be used. And, the position of the magnet body is not limited to the embodiment of the present invention. In the case of a galvanizing apparatus using gas wiping, it is most effective to prevent the vibration of the band steel between the wiping nozzles 20 and 22 in order for the thickness of the plating material to be uniform. For the above reason, it is preferable to place the magnet body near the edge of the band steel between the two wiping nozzles 20 and 22, which is the largest magnetic force of the magnet body.

In the present invention, the deflection rollers 16 and 18 are used to stabilize the galvanizing device, but the deflection rollers may cause vibration of the band steel due to the eccentricity of the rollers or the improper installation of the bearing part due to deformation by heat. Therefore, it is desirable not to use these deflection rollers to ensure the effect of the magnet body.

Referring to FIG. 2, the magnet bodies 34 and 38 are located near the edges of the strip steel 10, respectively. The magnet bodies 34 and 38 are provided with detectors 68 and 66 which are used to detect the gap between the edge surface of the strip steel 10 and the magnet body, respectively. As the detector, a photo detector or another type of position detector may be used. The signals from the detectors 66 and 68 are transmitted to the comparators 62 and 64, and the comparator is transmitted with a reference signal produced by the circuit 60 installed in advance.

Comparators 62 and 64 produce a signal corresponding to the actually detected signal and the reference signal. The output signals from the comparators 62 and 64 are transmitted to the control motors 48 and 49 through the amplifiers 70 and 72, respectively. The threaded rods 44 and 45 connected to the magnet bodies 34 and 38 are connected to the output sides of the control motors 48 and 49. Therefore, the magnet bodies can be moved when the threaded rod is moved by the motor.

According to this device, if the actual distance between the magnet body and the edge of the steel strip is not equal to a predetermined value, the control motor operates inconsistent with the signal indicating the deviation. Therefore, the magnet body is placed in a predetermined position.

In such a device, the distance between the magnet body and the edge of the strip is adjusted so that the magnetic force applied to the edge of the strip is kept constant.

Herein, the details of the magnet body are explained with reference to FIG. 3 and FIG. In the case of using a galvanizing apparatus, it is preferable to place the magnet body near the wiping nozzle for the same reason as above, but the magnet body is arranged under severe radiation heat from the melting material and the hot wiping gas. In particular, permanent magnets are changed by heat and magnetic force is easily reduced by heat.

To solve this problem, the magnet body 34 is a sealed cylindrical container 112 in which a cooling liquid circulates and surrounds a plurality of permanent magnets 102, 104, 106, and 108. Permanent magnets 102, 104, 106, and 108 are secured to T-shaped partitions 110 that create passages for cooling liquid in sealed containers 112. The magnets are fixed to the concave surface of the partition wall 110 and protrude toward the inner wall of the sealing container 112. At the upper end of the container, sealing caps 114 and 116 having an inlet pipe 52 and an outlet pipe 54 of cooling liquid are fixed. This sealed container is located near the edge surface of the strip steel 10 such that the magnets 102, 104, 106 and 108 face the edge surface of the strip steel 10 in front. In order to enhance the effect of the magnet body 34, the sealed container 112 preferably uses a nonmagnetic material such as stainless steel. In addition, the sealing container 112 is preferably made of a thin material. According to this embodiment, the decay of the magnetic force due to heat can be reduced. In addition, the molten material protruding from the magnet body and the sealing container 112 can be prevented from sticking.

In an embodiment of the present invention, the magnets 102, 104, 106, and 108 fixed to the partition wall 110 may be positioned to have a direction of a magnetic field such as SNS or NSN. The most effective magnetic field can then be obtained. In addition, it is recommended to use a nonmagnetic material to enhance the effect of the reverse vibration magnet.

5 is a graph showing the anti-vibration effect of the steel strip performed by the reverse vibration magnet, and the magnet is removed from the edge of the steel strip so that the magnetic force on the steel strip is not affected from 2 to 6 seconds. And as is clear from the graph, if the magnet is removed from the edge of the strip, the amplitude is about 10 mm, while if the magnetic force affects the strip, the amplitude of the vibration is maintained at 2-3 mm. The anti-vibration effect is more evident from the experimental steel with 1.20 mm thick steel, 1000 mm wide steel, linear velocity of 123 m / min and zinc content of 300 g / m2.

6 (a) and 6 (b) are experimental results showing the effect of with and without reverse vibration magnets. The results show that if no magnet is used, the maximum amplitude is 7 mm at the edge of the strip and the minimum amplitude is 4 mm in the middle. In addition, if no magnet is used, the cross section of the strip is concave or convex or bent backwards. And the length of bending or deformation, commonly called "canoing", is about 8 mm.

On the other hand, if the reverse vibrating magnet is located near the edge of the steel strip as shown in Fig. 6 (b), the amplitude of vibration (2.5 mm) is reduced as well as canoeing disappears.

The effect of the reverse vibrating magnet is further evident from the following Table 1, in which the plate thickness of the strip steel is measured according to the present invention using a conventional galvanizing apparatus without using the reverse vibrating magnet and the reverse vibrating magnet. The measured steel strip was used for the gas wiping method so that the steel strip having a thickness of 1.20 mm and a width of 1000 mm was plated at a linear speed of 123 m / min and zinc plated by an amount of 300 g / m 2. This measuring method was performed by what is called a "three-point method" according to Japanese Industrial Standard H0401, "Testing method of galvanized strip steel".

Ten specimens at equal distances to the width direction of the steel strip were sampled and the weight of zinc plated on the specimen was measured by the so-called "antimony chloride method".

As shown in Table 1, the thickness of the plating material by the conventional apparatus is not uniform. In particular, due to the deformation or bending of the band steel, the thickness of the plating material becomes thinner on the front side of the band steel and the middle part becomes thicker. On the back side of the band steel, the side parts become thicker and the middle part becomes thinner. On the other hand, according to the present invention using a reverse vibrating magnet, the thickness of the plating material is uniform in all parts of both sides of the strip steel, and these prove that the reverse vibrating magnet prevents bending or deformation of the strip steel as well as lateral vibration.

TABLE 1

Weight of zinc (g / ㎡)

7 shows the relationship between the gap between the edge of the strip steel and the surface of the magnet and the magnetic force applied to the strip steel.

The magnets used in these test results were formed from a number of rectangular magnet pieces made of cobalt magnets to make the magnet body as shown in FIG. The effective length of the magnet body facing the edge face of the strip steel is 500 mm.

As shown in FIG. 7, the magnetic force decreases with increasing distance. In addition, the thinner the band steel, the smaller the magnetic force. Considering the uniformity of the gap adjusting mechanism, it is preferable to maintain a gap of 4 to 6 mm in order to obtain a magnetic force of 5 to 25 kg.

8 shows another embodiment of the present invention in the case where the reverse vibration magnet is used in the continuous band steel inspection line. The strip steel 120 is moving over a pair of rollers 122 and 124. A detector 126 for detecting a scratch or thickness of the strip steel 120 using a laser beam or an X-ray beam is provided along the passage of the strip steel between the rollers 122 and 124, and is a reverse vibration magnet. Reference numeral 128 is provided near the edge of the strip of steel under the detector 126.

By this arrangement of the magnets 128, the detection error due to the vibration, deformation or bending of the strip steel is prevented against vibration, and the deformation of the strip steel is effectively suppressed by the magnet.

It is effective and desirable to make the magnets 132, 134 narrow and inclined as shown in FIG. This is because doing so increases the magnetic flux density acting on the edge of the steel strip.

Claims (1)

A device having a magnetic force generating device arranged along a traveling path in which a strip of magnetic material moves continuously, wherein the magnetic force generating device is separated from both ends of the plate width end portion of the strip of steel in the plate width direction and passes through a cross section of the strip steel. Arranged so as to be positioned on an extension line in the plate width direction, and a detector for detecting the position of the plate width end portion of the band steel again is provided, and the magnetic force generating device is moved in the plate width direction of the band steel based on a detection signal from the detector. A vibration preventing device, comprising: a moving device for adjusting the distance between the magnetic force generating device and the sheet width end of the strip steel.