JPH09108736A - Device for straightening shape of strip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To straighten the warp of a strip and to uniform the thickness of plating in a strip shape straightening device which is applied for a molten plating line of an iron manufacturing process. SOLUTION: Plural numbers of electric magnets 3 are arranged oppositely putting a strip 1 in between in a prescribed interval in the width direction of the strip 1, they are attached movable toward the face of the strip 1 on an attaching stand 11, and sensors 2 are arranged corresponding to these positions. The strip front face is blown with the air from a wiping nozzle just after plating and the thickness of plating on the front face is uniformed. When the strip 1 is warped, the sensor 2 detects the warping amount, inputs these signals to a controller, the electric magnet 3 is moved corresponding to the warping amount, because a proper exciting current is applied, warping is straightened, and the thickness control of air blowing is made precisely.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for straightening a strip in a steelmaking process line, and more particularly in a hot dip galvanizing line.

[0002]

2. Description of the Related Art In a hot dip galvanizing line, when galvanizing a running strip, the shape of the strip is corrected in order to make the galvanizing thickness of the strip surface uniform, and then the strip surface immediately after plating is applied. Air is blown onto the surface to control the plating thickness.

FIG. 3 is a view for explaining a method of controlling the plating thickness by a strip shape correcting device in a conventional hot dip galvanizing line. As shown
The strip 1 travels through the plating tank 10 and the molten zinc in the plating tank 10 is plated. A wiping nozzle 15 is installed near the outlet of the plating tank 10. Air is blown onto the surface of the strip 1 to control the plating thickness to be uniform.

However, the rolled strip 1 generally has a warp remaining in the width direction, so that the state of the air blown onto the surface of the strip 1 is not uniform and the control of the plating thickness is not performed well. .

Therefore, the sensor 12 and the electromagnet 13 are installed close to the wiping nozzle 15, and the sensor 1
At 2, the electric current is passed through the electromagnet 13 while constantly detecting the warp condition of the strip 1, the warp is corrected by the electromagnetic force, and then air is blown from the wiping nozzle 15 to control the plating thickness.

FIG. 4 is a view of the shape correcting device shown in FIG. 3 taken along the line AA, in which a plurality of electromagnets 13 are arranged at a predetermined interval in the width direction of the strip 1 so as to face the mounting base 11 ', and the sensor A plurality of 12 are also arranged corresponding to these positions. As described above, the sensor 12 detects the warp amount d of the strip 1 at the corresponding position and inputs it to the control device (not shown), and the control device compares the detected warp amount at each position, and the warp amount is large. For example, the electromagnet 1 shown in FIGS.
The exciting current of No. 3 is adjusted, the strip 1 of this portion is moved upward, and the portions (a) and (f) are moved downward,
The warp of the strip 1 is corrected as shown by the dotted line.

[0007]

As described above, the conventional strip shape correcting device has a plurality of electromagnets 13 arranged in the width direction with the strip 1 sandwiched therebetween and attached to the attachment base 11 'in a semi-fixed state. It is composed of a plurality of sensors 12 facing the strip 1 and arranged in the width direction thereof. The sensors 12 measure the distance from each mounting position to the strip 1, that is, the amount of warp of the strip 1 in the width direction, and measure it. The electromagnetic force of the electromagnet 13 is appropriately adjusted based on the value to correct the strip 1 into a flat state.

However, in the conventional apparatus, since the mounting position of the electromagnet 13 is fixed, the upper limit value of the electromagnetic force of each electromagnet 13 with respect to the strip 1 does not change. Therefore, the plate thickness is large and the amount of warpage is large. In the case of a strip, the electromagnet 13 has a insufficient capacity and the warp is not completely corrected, so that the plating thickness also becomes uneven. Further, in order to avoid this, unreasonably adopting an excessively large-capacity electromagnet has a problem such as an increase in equipment cost and running cost.

[0009]

In order to solve such a problem, the present invention arranges a plurality of sensors and electromagnets in the width direction so as to face a strip running at the outlet of a plating tank, In a strip shape straightening device for controlling the electromagnet by the detection signal of the strip position to straighten the shape of the strip and blow air to the strip from a wiping nozzle to control the plating thickness of the surface, the electromagnet is applied to the strip. And an arithmetic circuit that movably installs a position separated from each other, inputs a detection signal of the strip position by the sensor, and calculates a signal of a position movement amount of each electromagnet and a signal for exciting each electromagnet. A first drive circuit for controlling the position movement by receiving the signal from the arithmetic circuit and the electromagnet A strip comprising: a control device including a second drive circuit for controlling an exciting current, wherein the strip thickness is controlled by the wiping nozzle after the strip shape is corrected while the electromagnet is moved in position. There is provided a shape correcting device.

According to the present invention, the position of the strip immediately after passing through the plating tank and being plated on the surface, that is, the amount of warp in the strip width direction is detected by the sensor by such means, and the detection signal is obtained. It is input to the control device. In the control device, the arithmetic circuit determines the position control amount and electromagnetic force control amount of each electromagnet, and the output signals of the arithmetic circuit are sent to the first and second drive circuits, respectively, and the position movement amount and excitation of each electromagnet are excited. It is fed back to the electric current, which appropriately adjusts the electromagnetic force while moving each electromagnet in the strip direction, thus correcting the widthwise warp of the strip and then blowing air from the wiping nozzle onto the strip surface. The plating thickness is controlled uniformly.

[0011]

1 is a side view of a strip shape correcting device according to an embodiment of the present invention in a width direction of a strip. The overall structure is the same as that of a conventional example shown in FIG. doing. In the figure, 1 is a running strip, 2 is a plurality of sensors arranged at predetermined intervals in the width direction of the strip 1, 3 is an electromagnet, and a plurality of sensors are arranged at positions corresponding to the sensors 2 with the strip 1 sandwiched between them. It is attached to the table 11 so as to be vertically movable. With this configuration, the present apparatus is applied to the hot dip galvanizing line as in the conventional example of FIG. 3, and is installed at the outlet of the plating tank as in the figure.

FIG. 2 is a block diagram of the control device of the strip shape correcting device according to the present embodiment.
The output signal from the arithmetic circuit 4 and the arithmetic circuit 4 which inputs the signal from the subtracter 6 for comparing with the target value, the signal from the subtractor 6 and calculates and outputs the appropriate drive signal of the electromagnet 3. In response to this, a drive circuit 5a for moving the electromagnet 3 to a proper position and a drive circuit 5b for exciting and driving the electromagnet 3 at the proper position are formed.

As shown in these drawings, the present shape-correcting device has a plurality of electromagnets 3 arranged in the width direction with the traveling strip 1 interposed therebetween, and a plurality of sensors arranged in the width direction so as to face the strip 1. 2. Although not shown, as in FIG. 3, it is composed of a pair of wiping nozzles 15 installed close to the outlet of the plating tank 10, and its control device 7 has an arithmetic circuit 4, drive circuits 5a and 5b, and a subtractor 6 The electromagnet 3 is installed on the mount 11 under the control of the controller 7 so as to be positionally movable in the direction of the strip 1 (the moving mechanism is not shown).

Next, a control procedure in such a shape correcting device will be described. First, hot-dip galvanizing is performed while the strip 1 travels through the plating tank 10.
As in the conventional example of FIG. 3, air is blown from the wiping nozzle 15 onto the surface of the strip 1 immediately after plating that has left the plating tank 10, and the plating thickness is uniformly controlled. At this time, the wiping nozzle 1 exits the plating tank 10.
The position of each point in the width direction of the strip 1 traveling at five positions, that is, the amount of warpage is measured by each sensor 2 one by one.

This measurement signal is sent to the control device 7 as shown in FIG. 2, and after being compared with the target value by the subtracter 6, the comparison signal is sent to the arithmetic circuit 4.

The arithmetic circuit 4 calculates the required electromagnetic force of each electromagnet 3 and the electromagnet moving position required to obtain the electromagnetic force based on these comparison signals, and the respective output signals thereof are output to the drive circuit 5a, Sent to 5b.

The first drive circuit 5a moves the electromagnet 3 at a position that needs to be moved to an appropriate position so that an appropriate electromagnetic force can be applied. The second drive circuit 5b is for each electromagnet 3
Apply a proper excitation current to the.

With the drive circuits 5a and 5b, for example, in the example shown in FIG. 1, when the strip is warped as indicated by 1 '', the electromagnets below (a) and (f) of the electromagnet 3 are shown. Moves toward the strip 1 '' as shown by the dotted line, and a downward electromagnetic force is applied to the electromagnet (c),
The electromagnet on the upper side of (d) moves toward the strip 1 as shown by the dotted line, and an upward electromagnetic force is output, so that the strip 1 ″ is corrected to the flat state 1. Air is blown from the wiping nozzle 15 to the strip 1 whose shape has been corrected in this way, so that the plating thickness is uniformly controlled.

However, in the above, the strip 1 ''
As shown in FIG. 1, even when the warp shown in the strip 1 ′ remains after the straightening at the beginning of the control as shown in FIG. 1, the warp amount is measured by the sensor 2, The control amount is newly calculated by the same procedure as described above, whereby the electromagnet 3 is moved with higher accuracy, more appropriate electromagnetic force is output, and the warp of the strip 1 is completely corrected.

According to the embodiment described above, the sensor 2 detects the position of the strip 1 immediately after passing through the plating tank 10 and plating the surface thereof, that is, the amount of warp in the width direction. The detection signal is input to the arithmetic circuit 4 of the control device 7 to determine the position control amount and the electromagnetic force control amount of each electromagnet 3. The output signal of the arithmetic circuit 4 is sent to the first and second drive circuits 5a and 5b and fed back to the position movement amount and exciting current of each electromagnet, thereby moving each electromagnet 3 in the strip direction. While the electromagnetic force is adjusted appropriately.

By such control, after the warp of the strip 1 in the width direction is corrected, air is blown from the wiping nozzle 15 onto the surface of the strip 1 to uniformly control the plating thickness.

Further, since the electromagnet 3 is movably mounted on the mounting base 11 and can be moved when the amount of warp of the strip is large, the action of electromagnetic force can be increased and the electromagnet 3 can also be made to have a small capacity. You can

[0023]

As described above in detail, according to the strip shape correcting apparatus of the present invention, the amount of warp of the strip immediately after leaving the plating tank is measured by the sensor, and based on this measured value. A control amount is calculated by the control device, each electromagnet is moved in position by the first drive circuit of the control device based on the control amount, and the proper electromagnetic force is output by the second drive circuit. The warp of the strip can be completely corrected, so that the wiping nozzle can uniformly control the plating thickness.

Furthermore, since the electromagnet can be arbitrarily moved, its output (electromagnetic force) can be increased, which allows the shape correction to be performed using the electromagnet having a relatively small capacity, resulting in equipment cost and running. There are effects such as cost savings.

[Brief description of the drawings]

FIG. 1 is a side view of a strip shape correcting device according to an embodiment of the present invention in a strip width direction.

FIG. 2 is a block diagram of a control device of a strip shape correcting device according to an embodiment of the present invention.

FIG. 3 is an overall configuration diagram of a conventional strip shape correcting device.

FIG. 4 is a view taken in the direction of arrows AA in FIG. 3;

[Explanation of symbols]

 1 strip 2 sensor 3 electromagnet 4 arithmetic circuit 5a, 5b drive circuit 6 subtractor 7 controller 10 plating tank 11 mounting base 15 wiping nozzle

Claims (1)

[Claims] 1. A plurality of sensors and electromagnets are arranged in the width direction so as to face a strip running at the outlet of a plating tank, and the electromagnets are controlled by a detection signal of the strip position from the sensor to correct the shape of the strip. In the strip shape correcting device for controlling the plating thickness of the surface by blowing air to the strip from the wiping nozzle, the electromagnet is movably installed at a position separated from the strip, and the strip formed by the sensor is used. An arithmetic circuit that inputs a position detection signal and calculates a signal of the position movement amount of each electromagnet and a signal for exciting each electromagnet, and controls the position movement by receiving the signal from the arithmetic circuit. A control device comprising a first drive circuit and a second drive circuit for controlling an exciting current of the electromagnet. A strip shape correcting device, comprising: performing a shape correction of the strip while moving the electromagnet and then controlling a plating thickness by the wiping nozzle.