JP2011161465A - Device for controlling meandering in continuous processing line of steel band and method for controlling meandering - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out an optimum passing control of a strip by a meandering suppressing means at a downstream side when detecting abnormal meandering by a meandering suppressing means at an upstream side. <P>SOLUTION: In the continuous processing line of the steel band where a front end of a next strip 2 is welded to a terminal end of a strip 2 to continuously carry out processing, there are provided a plurality of the meandering suppressing means 5A-5D for suppressing the meandering of the strip, a meandering detecting means for detecting the meandering amounts of the respective meandering suppressing means and a meandering suppressing controlling means 32 for changing the control mode of the meandering suppressing means 5B-5D at the downstream side in response to whether or not an abnormal meandering state is detected by the meandering detecting means when passing a welding point. The meandering suppressing controlling means 32 permits meandering suppressing control when passing the welding point at the meandering suppressing means 5B-5D at the downstream side at a normal time that is not the abnormal meandering state, and interrupts the meandering suppressing control when passing a welding part at the meandering suppressing means 5B-5D at the downstream side at the abnormal meandering state. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a meandering control device and a meandering control method in a continuous processing line for steel strip such as surface treatment such as cold rolling, continuous annealing, and plating, and more particularly to a meandering control method at a welding point.

  In the continuous processing line of the steel strip, a center position control (CPC) device for centering the strip is provided, and the meandering of the strip is suppressed by this center position control device. In the continuous processing line of the steel strip, the front end of the next strip is welded to the end of the strip so as to pass through as a continuous strip. For this reason, the center position control device passes through the welded portion of the strip and the steady portion that does not include the welded portion. Normally, meandering suppression control is performed by the center position control device regardless of the welded portion and the steady portion. It is carried out.

  Whether the meandering deviation control between the meandering amount set value and the meandering amount actual value exceeds the threshold by the meandering control device that controls the center position control device. It has been proposed to judge whether or not the meandering deviation exceeds a threshold value, and to judge that the meander is abnormal and to output an alarm (for example, see Patent Document 1).

JP 02-84126 A

  However, in the conventional example described in Patent Document 1, it is disclosed that when the deviation between the meandering amount setting value and the meandering amount actual value exceeds a threshold value, it is determined that the meandering is abnormal and an alarm is issued. However, there is no mention of what to do when a meandering abnormality occurs, and when an alarm is issued, there is no way to stop the continuous processing line of the steel strip and prevent the amount of meandering from expanding. However, although it is avoided that an abnormal situation such as a break of the strip occurs, there is an unsolved problem that a decrease in the production amount due to stopping the continuous processing line of the steel strip becomes a problem.

Further, not only in the conventional example described in Patent Document 1, but in the conventional meandering suppression technology, when the degree of the wedge welding or the offset in the width direction is very large, the meandering is caused by excessive meandering correction or response delay. On the other hand, the strip breakage may occur due to the promotion.
Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and when an abnormal meandering is detected by the meandering suppression means on the upstream side, an optimum strip is detected by the meandering suppression means on the downstream side. An object of the present invention is to provide a meandering control device and a meandering control method in a continuous processing line of a steel strip capable of performing passage control.

  In order to achieve the above object, a meandering control device in a continuous processing line of a steel strip according to claim 1 of the present invention is a steel strip that performs continuous processing by welding the front end of the next strip to the end of the strip. A plurality of meandering restraining means for restraining meandering of the strip and meandering detecting means for detecting the meandering amount of each meandering restraining means are arranged in the continuous processing line, and whether the meandering abnormal state is detected when the meandering detecting means passes the welding point. A meandering suppression control means is provided for changing the control mode of the downstream meandering suppression means according to whether or not the meandering suppression control means passes through the welding point in the downstream meandering suppression means when the meandering abnormality is not normal. The meandering suppression control at the time of passing through the welded portion by the meandering suppression means on the downstream side is interrupted when the meandering suppression control at the time is allowed and in the meandering abnormality state.

According to a second aspect of the present invention, there is provided a meandering control device for a continuous treatment line for steel strips according to the first aspect of the invention, wherein the meandering suppression control means detects a meandering abnormal state by means of a meandering detection means upstream of a continuous annealing furnace. When this is done, meandering suppression control at the time of passing through the welding point is interrupted by at least meandering suppression means provided in the continuous annealing furnace.
According to a third aspect of the present invention, there is provided a meandering control device in the continuous processing line for steel strips according to the first or second aspect, wherein the meandering suppression means is a center position control device for centering the strip. It is characterized by.

  According to a fourth aspect of the present invention, there is provided a meandering control method for a continuous treatment line of a steel strip, wherein the meandering of the strip is applied to a continuous treatment line of a steel strip which is continuously processed by welding the front end of the next strip to the end of the strip. When a plurality of meandering suppression means for suppressing are arranged, it is determined whether or not a meandering abnormal state has occurred when passing through the welding point at least on the exit side of the upstream meandering suppressing means, and the determination result is a meandering abnormal state Further, the meandering prevention control at the time of passing through the welded portion is interrupted for the meandering suppression means on the downstream side.

Further, the welding point passage control method in the continuous processing line of the steel strip according to claim 5 is the invention according to claim 4, wherein the meandering suppression means on the entry side of the continuous annealing furnace is determined to be in a meandering abnormal state when passing through the weld. The meandering control during the passage of the welded portion is interrupted at least for the meandering suppression means in the continuous annealing furnace.
According to a sixth aspect of the present invention, there is provided a meandering control method for a steel strip continuous processing line, wherein the meandering suppression means is a center position control device for centering the strip.

  According to the present invention, when it is determined that the meandering abnormality is caused when the meandering suppression means disposed upstream of the continuous treatment line of the steel strip passes through the welded portion between the strips, the meandering suppression means on the downstream side causes the gap between the strips. The meandering suppression control is interrupted when the weld passes through, so that when meander welding or offset welding in the width direction occurs during welding, the meandering suppression control causes excessive meander correction or response delay. The amount of meandering can be promoted to reliably prevent the strip from breaking in the worst case. In this case, even if the meandering suppression means on the downstream side temporarily interrupts the meandering suppression control when passing through the welding point, the occurrence of large meandering is suppressed because a predetermined tension is applied to the strip itself. The

It is a line block diagram which shows an example of the continuous processing line of the steel strip with which implementation of this invention is provided. It is a perspective view which shows the specific example of a center position control apparatus. It is a block diagram which shows the control system of a CPC apparatus. It is a flowchart which shows an example of the meander suppression control processing procedure performed with the meander suppression control apparatus of an upstream CPC apparatus. It is a flowchart which shows an example of the meander suppression control processing procedure performed with the meander suppression control apparatus of a downstream CPC apparatus. It is a flowchart which shows an example of the meandering suppression monitoring process procedure performed with a high-order control apparatus. It is a time chart which shows the relationship between a strip deviation (meandering amount) and a hydraulic cylinder stroke when the welding point between strips passes a CPC apparatus. It is a time chart which shows the relationship between the strip deviation and hydraulic cylinder stroke in this invention and a prior art example.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a line configuration diagram of a continuous annealing line shown as an example of a continuous treatment line for steel strip used in the practice of the present invention. In the figure, reference numeral 1 denotes two pay-off reels for rewinding the strip 2 from the coil. The strip 2 supplied from the pay-off reel 1 is supplied to the welding machine 4 with the leading end and the trailing end cut by the entrance shear 3. The In this welding machine 4, the rear end of the preceding strip 2 and the front end of the following strip 2 are brought into contact with each other and welded.

  The strip 2 that has passed through the welding machine 4 is subjected to meandering suppression control by a center position control device (hereinafter referred to as CPC device) 5A serving as meandering suppression means for centering the strip 2 and suppressing meandering. It passes through and is annealed in, for example, a two-stage continuous annealing furnace 7. The continuous annealing furnace 7 includes a heating zone 7a, a soaking zone 7b, and a cooling zone 7c. The heating zone 7a and the cooling zone 7c are respectively provided with CPC devices 5B and 5C in the middle to meander the strip. Suppression control is performed.

The strip 2 annealed in the continuous annealing furnace 7 is temper-rolled by the temper rolling mill 11 through the exit-side looper 10 and then subjected to the meandering prevention control by the exit-side CPC device 5D and then welded by the divided shear 13. The portion is cut and wound up alternately on two tension reels 14.
As shown in FIG. 2, an example of a specific configuration of each of the CPC devices 5A to 5D includes a support frame 23 in which a pair of steering rolls 21 and 22 are spaced apart from each other by a predetermined distance so as to be rotatable in parallel. The support frame 23 is supported by a pivot pin 24 so that a frame portion 23a on the steering roll 21 side can be rotated in the horizontal direction, and a hydraulic cylinder 25 that rotates the support frame 23 in the horizontal direction on the frame portion 23b on the steering roll 22 side. The piston rod 25a is attached via a bracket 25b.

  Under the steering rolls 21 and 22, there are disposed an inlet side fixing roll 26 and an outlet side fixing roll 27 parallel to the steering rolls 21 and 22 with the support frame 23 being in the neutral position. Then, the strip 2 conveyed in the horizontal direction is turned upward by the entrance-side fixed roll 26, then turned horizontally by the steering roll 21, and further turned downward by the steering roll 22, and finally the exit side. The direction is changed in the horizontal direction by the fixed roll 27.

Further, meandering detectors 28a and 28b for individually detecting both end positions in the width direction of the strip 2 are disposed on the exit side of the steering roll 22, that is, the exit side of the CPC device, and the stroke of the piston rod of the hydraulic cylinder 25 is provided. For example, a stroke detector 29 for magnetically detecting is provided.
In the CPC devices 5A to 5D, when the strip 2 passes without meandering, the piston rod 25a of the hydraulic cylinder 25 is arranged so that the steering rolls 21 and 22 are in a neutral position parallel to the fixed rolls 26 and 27. Stroke is controlled. In this state, when the strip 2 meanders to the meandering detector 28a side so that the strip deviation amount is in the positive direction, the piston rod 25a of the hydraulic cylinder 25 sets the strip deviation amount to "center" the strip 2. Shrink to 0 ". On the contrary, when the strip 2 meanders to the meandering detector 28b side so that the strip deviation amount is in the negative direction, the piston rod 25a of the hydraulic cylinder 25 sets the strip deviation amount to “ It is expanded to be 0 ".

  The hydraulic cylinders 25 of the CPC devices 5A, 5B, 5C, and 5D are hydraulic drive devices 31A, 31B that hydraulically drive the meandering suppression control devices 30A, 30B, 30C, 30D and the hydraulic cylinder 25, as shown in FIG. , 31C, 31D. These meandering suppression control devices 30A to 30D receive the meandering amount actual values detected by the meandering detectors 28a and 28b arranged on the outlet side of the CPC devices 5A to 5D, and the stroke detector 29 The detected stroke detection value of the piston rod 25a of the hydraulic cylinder 25 is inputted. Further, as shown in FIG. 3, the maximum strip deviation ΔMmax is output from the meandering suppression control device 30 </ b> A to the host control device 32 as meandering suppression control means, and the meandering suppression control devices 30 </ b> B to 30 </ b> D from the host control device 32 are output. Meander control interruption commands Cib to Cid are input.

  The meandering suppression control device 30A of the upstream CPC device 5A executes the meandering suppression control process shown in FIG. In this meandering suppression control process, first, in step S1, the meandering amount actual value Mr detected by the meandering detectors 28a, 28b is read, and then the process proceeds to step S2 where the meandering amount is set from the preset meandering amount setting value Ms. After the actual value Mr is subtracted to calculate the strip deviation amount ΔM, the process proceeds to step S3.

  In this step S3, it is determined whether or not the strip deviation amount ΔM is in the range of the dead band ± M1 near “0”. When the strip deviation amount ΔM is within the dead band width, that is, when −M1 ≦ ΔM ≦ + M1. The process proceeds to step S4, where the stroke command value Cs for controlling the stroke of the hydraulic cylinder 25 to the neutral position is output to the hydraulic drive unit 31A, and then the process returns to step S1.

  On the other hand, if the determination result in step S3 indicates that the strip deviation amount ΔM exceeds the dead band width, the process proceeds to step S5 to determine whether or not the strip deviation amount ΔM is positive, and ΔM> 0. If YES, the process proceeds to step S6, where a stroke command value Cs for contracting the stroke of the piston rod of the hydraulic cylinder 25 from the neutral position according to the strip deviation amount ΔM is output to the hydraulic drive device 31A, and then the process returns to step S1. .

When the determination result in step S5 is ΔM <0, the process proceeds to step S7, and the stroke command value Cs for extending the stroke of the piston rod of the hydraulic cylinder 25 from the neutral position is output to the hydraulic drive device 31A. Return to step S1.
Further, the meandering suppression control devices 30B to 30D of the downstream CPC devices 5B to 5C execute the meandering suppression control process shown in FIG. In the meandering suppression control process, in the meandering control process of FIG. 4 described above, a step of determining whether or not the meandering control interruption command Ci input from the host controller 32 before step S1 is a logical value “1”. S0 is provided, and when the determination result of step S0 is that the meandering control interruption command Ci is a logical value “0”, the process proceeds to step S1 of FIG.

On the other hand, when the determination result of step S0 is that the meandering control interruption command Ci is the logical value “1”, the process proceeds to step S8, and the stroke for controlling the stroke of the hydraulic cylinder 25 to the neutral position regardless of the strip deviation amount ΔM. The command value Cs is output to the hydraulic drive devices 31B to 31D, the meandering suppression control is interrupted, and the process returns to step S1 in FIG.
The host control device 32 receives the strip deviation amount ΔM calculated by the meandering suppression control device 30 of the upstream CPC device 5 and also tracks the welding point between the welded strips. The welding point passage information output from 33 is input.

  The host control device 32 executes a meandering control monitoring process shown in FIG. In this meandering control monitoring process, first, in step S11, the welding point tracking information output from the welding point tracking device 33 is read, and then the process proceeds to step S12, where the welding point is determined based on the read welding point tracking information. It is determined whether or not it passes through the upstream CPC device 5A. When the determination result indicates that the welding point has not passed, the process jumps to step S15 described later, and when the welding point has passed, the process proceeds to step S13.

In this step S13, the strip deviation amount ΔM calculated by the meandering suppression control device 30A of the upstream CPC device 5A is read, and the maximum value ΔMmax of the read strip deviation amount ΔM is extracted. Next, the process proceeds to step S14, where it is determined whether or not the maximum value ΔMmax of the strip deviation amount ΔM exceeds a preset meandering threshold value ΔMth. If ΔMmax ≦ ΔMth, the meandering amount when passing through the welding point is allowed. It judges that it is within the range, and proceeds to step S15.
In this step S15, the meandering control interruption command Cib to Cid having the logical value “0” is output to the meandering suppression control devices 30B to 30D of the CPC devices 5B to 5D downstream from the CPC device 5A, and then the process returns to step S11. .

On the other hand, when the determination result of step S14 is ΔMmax> ΔMth, it is determined that the meandering amount when the welding point passes through the CPC device 5A is exceeding the allowable range, and the process proceeds to step S16. .
In step S16, it is determined whether or not the welding point has reached a predetermined range Lc (for example, 100 m) before and after the CPC device 5B on the downstream side as shown in FIG. 7, and the welding point is determined by the CPC device 5B. When the welding point has not reached the predetermined range Lc, the process waits until the welding point reaches the predetermined range Lc of the CPC device 5B. When the welding point has reached the predetermined range Lc, the process proceeds to step S17 and the meandering of the logical value “1” is performed. After outputting the control interruption command Cib to the meandering suppression control device 30B of the CPC device 5B, the process proceeds to step S18.

In this step S18, it is determined whether or not the welding point has passed the predetermined range Lc of the CPC device 5B. If it is within the predetermined range Lc, the welding point waits until it passes through the predetermined range Lc, and when the welding point has passed the predetermined range Lc. The process proceeds to step S19, and the meander control interruption command Cib having the logical value “0” is output to the meander suppression control apparatus 30B of the CPC device 5B, and then the process proceeds to step S20.
In this step S20, it is determined whether or not the welding point has reached a predetermined range Lc before and after the CPC device 5C on the downstream side, and if the welding point has not reached the predetermined range Lc of the CPC device 5C, welding is performed. The process waits until the point reaches the predetermined range Lc of the CPC device 5C. When the welding point reaches the predetermined range Lc, the process proceeds to step S21, and the meandering control interruption command Cic having the logical value “1” is passed through the meandering of the CPC device 5C. After outputting to the suppression control device 30C, the process proceeds to step S22.

In this step S22, it is determined whether or not the welding point has passed the predetermined range Lc of the CPC device 5C. If the welding point is within the predetermined range Lc, the process waits until the welding point passes the predetermined range Lc. If it has passed, the process proceeds to step S23, and a meandering control interruption command Cic having a logical value “0” is output to the meandering suppression control apparatus 30C of the CPC device 5C, and then the process proceeds to step S24.
In this step S24, it is determined whether or not the welding point has reached a predetermined range Lc before and after the CPC device 5C on the downstream side, and if the welding point has not reached the predetermined range Lc of the CPC device 5C, welding is performed. The process waits until the point reaches the predetermined range Lc of the CPC device 5C. When the welding point reaches the predetermined range Lc, the process proceeds to step S25, and the meandering control interruption command Cic having the logical value “1” is sent to the CPC device 5C. After outputting to the meandering suppression control device 30C, the process proceeds to step S26.

  In this step S26, it is determined whether or not the welding point has passed the predetermined range Lc of the CPC device 5D. If the welding point is within the predetermined range Lc, the process waits until the predetermined range Lc elapses. The process proceeds to step S27, and the meandering control interruption command Cid having the logical value “0” is output to the meandering suppression control device 30D of the CPC device 5D, and then the process returns to step S11.

Next, the operation of the above embodiment will be described.
Now, it is assumed that the strip 2 is rewound from one payoff reel 1. The strip 2 unwound from the payoff reel 1 is centered by the first CPC device 5A. The CPC device 5A reads the meandering amount actual value Mr detected by the meandering detectors 28a and 28b arranged on the outlet side (step S1). Next, the strip deviation amount ΔM is calculated by subtracting the meandering amount actual value Mr from the meandering amount setting value Ms (step S2).

At this time, when the strip 2 hardly wobbles and the strip deviation amount ΔM is within the dead zone, the stroke command value Cs for controlling the stroke of the piston rod 25a to the neutral position with respect to the hydraulic cylinder 25 of the CPC device 5A. Is output to the hydraulic drive device 31A (step S4).
For this reason, the stroke of the piston rod 25a of the hydraulic cylinder 25 of the CPC device 5A is controlled to the neutral position by the hydraulic drive device 31A, thereby controlling the steering rolls 21 and 22 to be parallel to the fixed rolls 26 and 27. The For this reason, the strip 2 is allowed to pass through without correcting the meandering amount.

  Further, when the strip deviation amount ΔM exceeds the dead zone, a hydraulic pressure driving device uses a stroke command value Cs for performing centering for returning the strip 2 to the center position depending on whether the strip deviation amount ΔM is positive or negative. 31A (step S6 or S7), and the piston rod 25a of the hydraulic cylinder 25 is contracted or extended from the neutral position by the hydraulic drive device 31A, thereby centering the strip 2 to the central position.

During the meandering suppression control by the CPC device 5A, since the welding point of the strip 2 does not pass through the CPC device 5A, the meandering control interruption commands Cib to Cid of the logical value “0” from the upper control device 32 are downstream CPC devices. It is output to 5B to 5D (step S15).
The strip 2 that has passed through the CPC device 5 </ b> A passes through the entry-side looper 6 and is heated in the heating zone 7 a of the continuous annealing furnace 7. The heating zone 7a is centered by the CPC device 5B disposed therein. In the CPC device 5B, a meandering control interruption command Cib having a logical value “0” is supplied from the host control device 32 to the meandering suppression control device 30B. Therefore, the meandering suppression control device 30B performs the meandering suppression control processing in steps S1 to S7 in the meandering suppression control device 30B of FIG. 5, and the strip 2 is centered to suppress meandering.

Thereafter, the strip 2 passes through the soaking zone 7b, is cooled in the cooling zone 7c, and is annealed.
Even in the cooling zone 7c, the strip 2 is centered by the CPC device 5C to suppress meandering.
After the strip 2 annealed in the continuous annealing furnace 7 passes through the exit side looper 10 and is temper-rolled by the temper rolling mill 11, the strip 2 is subjected to the meandering prevention control by the exit side CPC device 5D and then the tension is applied. It is wound on one of the reels 14.

  In the state where the strip 2 is continuously annealed, when the rewinding of the strip 2 from one payoff reel 1 is completed and the strip 2 is rewound from the other payoff reel 1, the strip 2 is first removed from the entry side looper 6. As a state of paying out, the rear end of the strip 2 currently rewound by the entrance shear 3 is cut. Before or after cutting the rear end of the strip 2, the front end of the strip 2 to be rewound is cut.

  Next, the rear end of the current strip 2 and the front end of the new strip 2 are butt-welded at the welding position of the welding machine 4 and welded. When the welding of the strip 2 is completed, the strip 2 is fed out while the stripping out of the strip 2 is finished by the entry side looper 6 and the storage state is maintained. Thereby, the welding point which welded the strips 2 starts a movement. The movement position of the welding point is tracked by the welding point tracking device 33.

  When the welding point of the strip 2 reaches the upstream CPC device 5A, the CPC device 5A executes meandering suppression control processing. At this time, when the welding point of the strip 2 is in a normal state in which offset welding or cross-shaped welding is not performed, meandering by centering the strip 2 with the CPC device 5A can be suppressed. However, if offset welding in which the strips 2 to which the welding points of the strips 2 are connected causes offset in the width direction, or if the strips 2 sandwiching the welding points are in a U-shaped welding, the CPC device 5A meanders. When the suppression process is executed, the amount of meandering is promoted by excessive meandering correction and response delay.

For this reason, when the welding point of the strip 2 reaches the CPC device 5A, the host control device 32 reads the strip deviation amount ΔM calculated by the meandering suppression control device 30A and extracts the maximum value ΔMmax of the strip deviation ΔM (step S13). ). When the extracted maximum value ΔMmax is less than or equal to the threshold value ΔMth, it is determined that normal meandering suppression control is being performed, and meandering control interruption commands Cib to Cid having a logical value “0” are assigned to the CPC devices 5B to 5D. Output to the meandering suppression control devices 30B to 30D.
For this reason, in each CPC apparatus 5B-5D, when the welding point of the strip 2 passes, the meandering suppression control process similar to the normal time in which the part which is not a welding point passes is performed, and the meandering of the strip 2 is suppressed. To do.

  However, when the welding point of the strip 2 passes through the upstream CPC device 5A, if the offset welding or the U-shaped welding occurs, the maximum value ΔMmax of the strip deviation amount ΔM as shown by the solid line in FIG. Is in a state exceeding the threshold value ΔMth in the positive direction, for example. For this reason, the meandering suppression control device 30A outputs a stroke command value Cs that suppresses meandering to the hydraulic drive device 31A based on the strip deviation amount ΔM. Accordingly, the stroke of the piston rod 25a of the hydraulic cylinder 25 of the CPC device 5A has a predetermined response delay from the strip deviation amount ΔM in a phase opposite to the strip deviation amount ΔM from the neutral position as shown by a broken line in FIG. Controlled in the negative direction.

  Thus, when the strip deviation amount ΔM in the upstream CPC device 5A exceeds the threshold value ΔMth, the upper control device 32 has a meandering abnormality because the maximum value ΔMmax of the strip deviation amount ΔM exceeds the threshold value ΔMth. When the welding point tracking information from the welding point tracking device 33 is read and the welding point reaches the next CPC device 5B, a logical value “between the predetermined range Lc before and after the welding point passes is determined. 1 "meander control interruption command Cib is output.

  For this reason, in the CPC device 5B, as shown in FIG. 8B, the meandering control interruption command Cib becomes a logical value “1” in the predetermined period T1 corresponding to the predetermined range Lc before and after the welding point passes. Therefore, the stroke command value Cs for controlling the stroke of the piston rod 25a of the hydraulic cylinder 25 to the neutral position is output to the hydraulic drive device 31B. Therefore, the meandering suppression control is not performed in the CPC device 5B, and the welding point is allowed to pass without performing the meandering suppression control. For this reason, as shown in FIG. 8A, the strip deviation amount ΔM changes according to the shape of the welding point, but does not cause a hunting phenomenon due to excessive meandering suppression control.

  Thereafter, when the predetermined period T1 elapses and the welding point of the strip 2 finishes passing between the predetermined range Lc before and after the CPC device 5C, a meandering control interruption command Cib having a logical value “0” is issued from the host controller 32. By outputting to the meandering suppression control device 30B of the CPC device 5B, the meandering suppression control is resumed by the meandering suppression control device 30B, and the meandering suppression control is performed so that the strip deviation amount ΔM is within the dead band width near zero. Is called.

Even when the meandering suppression control process is interrupted by the CPC device 5B, since the strip 2 is given a predetermined tension for transporting, the strip 2 is centered by this tension. A significant increase in the amount of meandering is suppressed.
Incidentally, when the meandering suppression control process is executed in the CPC device 5B as in the conventional example, the strip deviation amount ΔM increases in the positive direction, for example, as shown in FIG. Accordingly, the piston rod 25a of the hydraulic cylinder 25 is stroked in the negative direction opposite to the strip deviation amount ΔM, as shown in FIG.

For this reason, the strip deviation amount ΔM immediately after the welding point has passed is largely returned in the negative direction as shown in FIG. 8C, and the piston rod 25a of the hydraulic cylinder 25 is correspondingly moved as shown in FIG. Strokes in the positive direction as shown in FIG. The stroke of the piston rod 25a converges to the neutral position while being attenuated as the strip deviation amount ΔM converges to zero.
As described above, when the meandering suppression control is executed when the welding point passes, the hunting phenomenon occurs in the stroke of the hydraulic cylinder 25 due to the correction of the strip position by the excessive meandering suppression control. For this reason, a buckling phenomenon occurs in the vicinity of the welding point of the strip 2, or in the worst case, the strip may be broken.

However, as in this embodiment, if the meandering suppression control is interrupted when the welding point passes, the excessive meandering suppression control is suppressed, and a hunting phenomenon does not occur in the stroke of the hydraulic cylinder 25 of the CPC device 5B. It is possible to reliably prevent a buckling phenomenon from occurring in the strip 2 and the strip 2 from breaking.
Thereafter, meandering suppression control is interrupted in the same manner as described above for a predetermined period T1 before and after the welding point of the strip 2 also passes through the downstream CPC devices 5C and 5D.

  In the above-described embodiment, the case where the meandering suppression control is interrupted in all the CPC devices 5B to 5D downstream from the CPC device 5A has been described. The meandering suppression control of the CPC devices 5B and 5C in the continuous annealing furnace 7 that needs to be performed may be interrupted. In addition, when a plurality of CPC devices are disposed on the upstream side of the continuous annealing furnace 7, when the strip deviation amount ΔM exceeds the threshold value ΔMth in any of the CPC devices on the upstream side of the continuous annealing furnace 7. The meandering suppression control of the CPC devices 5B and 5C may be interrupted.

Moreover, in the said embodiment, although the case where meander suppression control was performed based on the flowchart of FIGS. 4-6 was demonstrated, meander suppression control is not limited to the process of the said flowchart, and the point is upstream. When the meandering amount of the welding point becomes excessive in the CPC device, the meandering suppression control of the welding point in the downstream CPC device may be interrupted.
Furthermore, in the said embodiment, although the case where the CPC apparatus was arrange | positioned at four places of the entrance side and exit side of the continuous annealing furnace 7, and the inside of a continuous annealing furnace was demonstrated, it is not limited to this, The side looper 6, the exit side looper 10 and the like may be provided with CPC devices, and these may be controlled in the same manner as the CPC devices 5B to 5D.

Furthermore, in the above embodiment, the case where the CPC devices 5A to 5D have the configuration shown in FIG. 2 has been described. However, the present invention is not limited to this, and two strip guide rolls arranged in parallel have a Z shape. A strip is wound around and inserted, and any configuration such as a configuration in which one of the rolls is a steering roll can be used. In short, the strip 2 only needs to have a function of centering.
Furthermore, in the above embodiment, the case where the continuous annealing line is applied as the continuous treatment line of the steel strip has been described. However, the present invention is not limited to this, and the surface of the cold rolling line in which the rolling mill is disposed, the surface of plating, etc. The present invention can also be applied to a continuous processing line of any other steel strip such as a processing line.

  DESCRIPTION OF SYMBOLS 1 ... Pay-off reel, 2 ... Strip, 3 ... Shear, 4 ... Welding machine, 5A-5D ... Center position control (CPC) apparatus, 6 ... Incoming looper, 7 ... Continuous annealing furnace, 10 ... Outlet looper, 11 ... Temper rolling mill, 13 ... split shear, 14 ... tension reel, 21, 22 ... steering roll, 23 ... support frame, 25 ... hydraulic cylinder, 28a, 28b ... meander detector, 30A-30D ... meandering suppression control device, 31A 31D ... hydraulic drive device, 32 ... high-order control device, 33 ... welding point tracking device

Claims (6)

A plurality of meandering suppression means for suppressing meandering of the strip and a meandering amount for detecting the meandering of each meandering suppression means on a continuous processing line of a steel strip for continuously processing by welding the front end of the next strip to the end of the strip Detection means is provided, provided with meander suppression control means for changing the control mode of the meander suppression means on the downstream side depending on whether or not a meandering abnormal state is detected when the meander detection means passes the welding point,
The meandering suppression control means allows the meandering suppression control when the welding point passes through the downstream meandering suppression means when the meandering abnormality state is not normal, and when the meandering abnormality state, the meandering suppression means on the downstream side A meandering control device in a continuous processing line of a steel strip, wherein meandering suppression control when passing through a weld is interrupted.   The meandering suppression control means suppresses meandering when passing through a welding point at least in the meandering suppression means provided in the continuous annealing furnace when a meandering abnormality state is detected by the meandering detection means upstream of the continuous annealing furnace. The meandering control device in the continuous processing line of the steel strip according to claim 1, wherein the control is interrupted.   The meandering control device according to claim 1 or 2, wherein the meandering suppression means comprises a center position control device for centering the strip.   When a plurality of meandering restraining means for restraining meandering of the strip are arranged on a continuous treatment line of a steel strip that is continuously processed by welding the front end of the next strip to the end of the strip, at least the meandering restraining means on the upstream side It is determined whether or not a meandering abnormal state has occurred when passing the welding point on the exit side, and when the determination result is a meandering abnormal state, the meandering prevention control when the welding part passes is interrupted for the meandering suppression means on the downstream side A meandering control method in a continuous processing line for steel strips.   When the meandering suppression means on the entry side of the continuous annealing furnace is determined to be in a meandering abnormal state when passing through the welded portion, at least the meandering control when passing through the welded portion of the meandering suppressing means in the continuous annealing furnace is interrupted The meandering control method in the continuous processing line of the steel strip of Claim 4 characterized by these.   The meandering control method according to claim 4 or 5, wherein the meandering suppression means is a center position control device for centering the strip.

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