JP2002285248A - Method for controlling speed of continuous treatment line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deceleration of any unnecessary center section speed, and to improve the mean speed by efficiently controlling the plate passing speed even when the looper capacity is insufficient for the stationary center section speed. SOLUTION: The deceleration rate of the non-stationary speed of the center section is set to be a predetermined value, deceleration to the non-stationary speed at the deceleration rate of the center section speed is completed before starting the deceleration of the inlet side section or the outlet side section for a handling work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the speed of a continuous processing line, and more particularly to a method for controlling a continuous processing line of a metal strip such as a continuous annealing line of a steel strip (also referred to as a steel strip) or a continuous plating line. In a facility having a suitable strip storage device (hereinafter referred to as "looper") capable of continuous processing, continuous processing capable of efficiently controlling the passing speed even when the looper capacity is insufficient. The present invention relates to a line speed control method.

[0002]

2. Description of the Related Art As shown in FIG. 1, for example, a continuous processing line for a metal strip S such as a steel strip is generally roughly divided into three sections: an entrance section 1, a center section 3, and an exit section 5. It comprises loopers 2 and 4 arranged between the entry section 1 and the center section 3 and between the center section 3 and the exit section 5, respectively.

The entry section 1 is primarily intended for dispensing strips wound into a coil C. The entry section 1 is provided with, for example, a welding machine 6 for welding and connecting the sequentially paid out coils. The central section 3 is a section for performing main processing such as heat treatment, chemical processing, and plating. The exit section 5 is mainly composed of strips S that have been processed.
Is cut to a predetermined length by, for example, a cutting machine 7 and wound around the coil C again.

[0004] The looper continuously strips S to the central section 3 even when the inlet section 1 or the outlet section 5 stops due to welding or cutting of the coil.
Or a strip storage device for continuously dispensing strips S from the central section 3.

Conventionally, the length of the strip S which can be temporarily stored in the looper (hereinafter referred to as "looper capacity") is
Considering the low speed operation time including the stop of the entrance section 1 and the exit section 5 and its speed, and the maximum speed of the central section 3, welding or cutting is possible even when the central section 3 is at the maximum speed. It was designed to be.

[0006] On the other hand, after the metal strip continuous processing line is constructed, the center section 3 may be equipped with additional equipment to increase the passing speed in the central section in order to improve productivity. In such a case, the capacity of the looper installed on the inlet or outlet side is often insufficient relative to the processing capacity of the central section, and welding or welding on the inlet or outlet section is During handling operations such as coil cutting, the speed of the central section had to be lower than the steady speed. At this time, since the operator manually adjusts the line speed, it is not possible to concentrate on the handling work on the entrance side or the exit side. However, there was a problem that productivity was poor.

When the passing speed of the central section is reduced in order to perform the coil switching work on the entrance or exit section, for example, JP-A-6-126333 or JP-A-6-126333 is used in order to reduce the decrease in production due to the reduction. 10
Techniques such as -35968 have been proposed.

Japanese Patent Application Laid-Open No. 6-126333 discloses a continuous steel sheet processing line in which a coiled steel sheet is discharged from an entry section, treated in a central section, and then wound again in a coil shape through an exit section. The remaining amount of the entrance looper and the exit looper is managed from the set maximum required stop time, the minimum operable speed, and the steady speed determined for each coil required for the handling operation in the entry section or the exit section. The deceleration rate of the central section speed is determined, and the remaining amount of the looper (the amount of metal strip stored in the looper) of the entrance looper or the exit looper is determined by the deceleration rate and the set minimum looper remaining amount. It is described that deceleration is started at the deceleration rate when the following occurs.

Japanese Patent Application Laid-Open No. 10-35968 discloses a case in which the work time in the entry or exit section becomes longer than the time assumed at the time of design due to re-working of welding or re-working. In addition, the operator predicts the time that will occur for the work to be performed from now on, and selectively presses the work time extension button a predetermined number of times based on the prediction. It is described that a line speed at a central portion is automatically calculated by a host computer (P / C) in order to change the extension time and the speed is set.

[0010]

However, in the former technique disclosed in Japanese Patent Laid-Open No. 6-126333, the capacity of the looper is insufficient with respect to the steady speed of the center section as described above, and the speed of the center section is set near the maximum speed. In facilities where coil switching cannot be performed while maintaining the steady speed set by the value, the timing of deceleration is too late, so there is a risk of buckling and meandering in the furnace, and sudden acceleration or deceleration is performed. There was a problem that had to be done.

In the latter technique disclosed in Japanese Patent Laid-Open No. 10-35968, in a facility where the capacity of the looper is insufficient for the steady speed of the central section, it is necessary to press a push button for each coil. In addition, the work becomes complicated, and if the operator forgets to press the button, a line trouble occurs, and the production efficiency may be reduced.

According to the present invention, in order to perform the above-described handling work or the like, when the speed of the entry section or the exit section is reduced, the capacity of the looper is insufficient, and the center section speed must be reduced. In such equipment, the decrease in production volume due to the slowing down of the central section passing speed is minimized without the occurrence of troubles such as buckling and meandering caused by rapid deceleration in the central section due to timing delay. And to secure good production efficiency.

[0013]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a method for continuously processing a metal strip having an inlet section, a center section, and an outlet section. In controlling, the unsteady speed and deceleration rate of the central section are set to predetermined values, and the deceleration of the central section speed is started before the deceleration of the entrance section or the exit section for handling work is started. The processing at the non-stationary speed at a rate is completed.

At this time, the acceleration rate of the central section speed is set to a predetermined value, and the speed in the entrance section or the exit section is accelerated after the processing at the non-stationary speed of the central section speed. It is preferable to start accelerating the central section speed at the acceleration rate at the time when the speed of the central section coincides with the unsteady speed.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

First, a first embodiment of the present invention suitable for central section speed control at the time of performing entrance-side handling, such as coil switching at the entrance, will be described in detail with reference to FIG.

In a steady state, the entry section speed V1
Is the same speed as the steady speed Vc of the central section, ie, V
1 = Vc. In order to increase productivity, Vc is often operated near the maximum speed of continuous processing equipment.

In the present embodiment, the unsteady state speed Vcd1 and the deceleration rate D1 of the central section for performing the handling operation in the entrance section are set to predetermined values.
As this predetermined value, for example, Vcd1 is determined based on information on the metal strip such as the width and thickness of a metal strip (also referred to as a metal band) that affects welding time and the like, or further information on the line on a welding machine or the like. The time required for handling may be predicted empirically, and a speed sufficient to secure this time may be used. D1 may be adjusted so that the metal strip to be passed is formed in a meandering or buckling manner in order to secure productivity. What is necessary is just to set the value to the maximum value within a range that does not cause trouble. Vcd1 and D1 may be values empirically obtained. In order to arbitrarily set the predetermined value, for example, a structure of an operation device that can be manually input so as to be arbitrarily set may be adopted. Note that Vcd1 and D1 are predicted from coil information and the like instead of manual input.
This value may be incorporated in the control system of the central section speed in advance.

As described above, Vcd1 and D1 are set to predetermined values in advance, and before the deceleration of the entry section for the handling operation is started, the speed Vcd1 from the steady state speed Vc of the central section speed to the unsteady state speed Vcd1 is set. The deceleration start timing of the central section is determined so that the deceleration to the center section is completed.

That is, the center section speed deceleration start time T
c1 is the V section with respect to the time T1 at which the previously set entry section speed is instructed to start deceleration.
Considering the time required to change the central section speed to the unsteady speed determined from c, Vcd1, and D1, the deceleration timing is determined so that this time can be secured.
When considering the time required for this change, the setting may be made for each coil, but the metal strips to be processed may be grouped to some extent so that the same time is given within the same group.

The time required for handling such as coil replacement at the entry side is predicted in advance from information on the metal strip or information on the line equipment such as a welding machine. In order to secure the time required for handling the metal strip, When the remaining amount of the coil reaches a predetermined value, the speed V1 of the entry section is released from synchronization with the speed Vc of the center section, and is set to start deceleration independently.

In the present embodiment, the deceleration rate D1 of the central section speed and the speed Vcd1 after deceleration are set as described above, and before the deceleration of the entrance section for handling work is started, The deceleration of the center section is completed, and the speed of the center section is reduced to Vcd1.

The entry section speed is synchronized with the center section speed until a time point T1 at which a deceleration start instruction for handling operation, which has been set conventionally, is issued. I do. Therefore, the same amount of the looper remaining amount as after the steady speed can be secured from Tc1 to T1.

In FIG. 2, the entry section speed is
Although the deceleration of the center section speed is started at a certain timing of passing the plate at Vcd1, the deceleration of the center section speed may be started so that T1 is a time immediately after the entry section speed becomes Vcd1. .

As described above, by controlling the center section speed, there is no danger of suddenly reducing the center section speed, and the center section speed can be reduced without causing the occurrence of buckling and meandering troubles. The decrease in production volume due to deceleration can be minimized, and good production efficiency can be ensured.

Next, the speed of the central section when the entrance section is accelerated after the handling in the entrance section is completed will be described. When the handling in the entry section is completed, the entry section starts accelerating at time T2. Prior to acceleration in this entry section,
The acceleration rate A1 of the predetermined center section speed is arbitrarily set, and the time Tc at which the entry section speed reaches Vcd1
Preferably, at 2, the central section speed is accelerated to Vc at A1.

The acceleration rate A1 is, like the deceleration rate D1, a maximum value within a range in which the metal strip to be passed does not cause a passing trouble such as meandering or buckling in order to secure productivity. The value may be determined empirically so that In order to arbitrarily set the predetermined value, for example, a structure of an operation device that can be manually input so that the value can be arbitrarily set may be adopted. When setting Vcd1 and D1, A1 is set. Is also good. Instead of manual input, A1 may be predicted before the sheet is passed from the coil information and the like, and this value may be incorporated in advance in the control system of the central section speed like Vcd1 and D1.

By accelerating the central section speed in this way, the passing time of the central section at the unsteady speed can be minimized without causing a passing trouble, thereby enabling efficient operation. it can.

At this time, the speed of the entry section is increased to a speed greater than Vc at a predetermined acceleration rate after the handling on the entry side is completed, and the speed is maintained. The remaining amount is sufficient, specifically 1
After accumulating close to 00%, it is sufficient to tune to the center section speed Vc.

FIG. 3 shows an example of the processing procedure of the above-described central section speed control method.

Next, a second embodiment of the present invention, which is applied to central section speed control when performing outlet side handling such as coil switching in the outlet side section, will be described in detail with reference to FIG.

First, in the steady state, the outlet section speed V2 is passed as the same speed as the steady speed Vc of the central section, that is, V2 = Vc, as in the inlet section.

In this embodiment, the unsteady state speed Vcd2 and the deceleration rate D2 for handling the central section handling operation are set to predetermined values. The predetermined value can be obtained from information on the metal strip, such as the number of samples taken for the inspection of the metal strip, which affects the time required for cutting the metal strip, or information on the line of a cutting machine or the like. It is sufficient to empirically predict the time required for the handling on the side, and the speed should be such that this time can be secured. In order to secure the productivity, the metal strip to be passed is formed in a meandering or buckling manner in order to secure the productivity. The value may be empirically determined so as to be the maximum value within a range in which there is no trouble in passing the sheet. In order to arbitrarily set the predetermined value, for example, a structure of an operation device that can be manually input so as to be arbitrarily set may be adopted. Instead of manual input, Vcd2 and D2 may be predicted from coil information and the like, and the values may be incorporated in the control system of the central section speed in advance.

As described above, Vcd2 and D2 are set to predetermined values in advance, and before the start of deceleration of the exit section for handling work, the speed Vcd2 from the steady speed Vc2 of the central section speed to the unsteady speed Vcd2. The deceleration start timing of the central section is set in the same manner as the deceleration of the entry section so as to complete the deceleration to

That is, the central section speed deceleration start time T
c3 corresponds to the time V3 at which a command to start deceleration of the exit section speed, which has been set conventionally, is issued.
The deceleration timing may be determined in consideration of the time required for changing the central section speed to the unsteady speed obtained from c, Vcd2, and D2 so as to secure this time. When considering the time required for this change, the setting may be made for each coil, but the metal strips to be processed may be grouped to some extent so that the same time is given within the same group.

The time required for handling such as cutting of the metal strip at the exit side is predicted in advance from the information on the metal strip or the information on the line of the cutting machine or the like. Then, the speed V2 of the exit section is released from being synchronized with the speed Vc of the center section, and is set to start deceleration independently.

In the present embodiment, the deceleration rate D2 of the central section speed and the speed Vcd2 after the deceleration are set as described above, and before the deceleration of the exit section for handling work is started, The deceleration of the center section is completed, and the speed of the center section is reduced to Vcd2. Until a time point T3 at which an instruction to start the deceleration of the exit section for the handling operation is issued, the exit section speed is synchronized with the center section speed, and the deceleration is similarly performed when the center section speed is reduced. Accordingly, the same amount of the remaining amount of the looper as that at the time of the steady speed can be secured while the exit section speed is decelerating to the center section speed.

Next, the speed of the central section when the handling of the exit section is completed and the exit section is accelerated will be described. When the handling in the exit section ends, the exit section starts accelerating at time T4. Before accelerating in this exit section,
The acceleration rate A2 of the predetermined center section speed is arbitrarily set, and the time Tc at which the output section speed reaches Vcd2
Preferably, at 4, the central section speed is increased to Vc at A2.

The acceleration rate A2 is equal to the deceleration rate D2
Similarly to the above, the value may be empirically determined so that the metal strip passing therethrough has the maximum value within a range in which a trouble such as meandering or buckling does not occur in order to secure productivity. Further, in order to arbitrarily set the predetermined value, for example, a device structure that allows manual input so that the value can be arbitrarily set may be adopted, and A2 may be set when the Vcd2 and D2 are set. . Instead of manual input, A2 may be predicted from the coil information or the like before passing, and this value may be previously incorporated in the control system of the central section speed in the same manner as Vcd2 and D2.

By accelerating the central section speed in this way, the passing time of the central section at the unsteady speed can be minimized without causing a passing trouble, thereby enabling efficient operation. it can.

At this time, the speed of the exit section is
As before, after handling on the exit side is completed, after accelerating to a speed greater than Vc at a predetermined acceleration rate, this speed is maintained, and the looper remaining amount is sufficient, specifically, close to 100%. After accumulation, it may be tuned to the central section speed Vc.

The central speed control as described above may be performed when there is a looper having the above-mentioned problem.
When a looper having the above-mentioned problem is installed on both the entrance side and the exit side, the exit side may perform the above-described control on the entrance side,
If only the entry side or only the exit side has, it may be performed only on the side that needs to be dealt with.

[0043]

EXAMPLE The control method of the present invention was applied to a continuous annealing furnace having a looper on the entrance side and the exit side, and its effect was examined. The comparison is a conventional method in which all of the central section speed control is manually performed by an operator. According to the present invention, productivity (production volume per unit time) is higher than in the past
Was improved by 7%.

[0044]

According to the present invention, even when the capacity of the looper installed on the entrance side or the exit side is low, it is possible to pass the metal strip during the handling operation in the entrance section or the exit section of the continuous processing line. While securing the flatness, the deceleration of the central section speed to the unsteady speed can be suppressed to the minimum necessary level. Accordingly, unnecessary deceleration of the central section speed can be prevented, the average speed can be improved, and productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a continuous processing line for a metal strip to which the present invention is applied.

FIG. 2 is a time chart for explaining a control method of the central section speed according to the first embodiment of the present invention, which is applied when performing inbound handling.

FIG. 3 is a flowchart illustrating an example of a processing procedure according to the first embodiment;

FIG. 4 is a time chart for explaining a control method of a central section speed according to a second embodiment of the present invention applied when performing outgoing side handling;

[Explanation of symbols]

 S ... metal strip 1 ... entry section 3 ... center section 5 ... exit section 6, 7 ... looper

Claims (2)

[Claims] In controlling a central section speed of a metal strip in a line for continuously processing a metal strip having an inlet section, a central section, and an outlet section, an unsteady state speed and a deceleration rate of the central section are controlled. Set to a predetermined value, and complete the deceleration of the central section speed to the unsteady speed by the deceleration rate before starting the deceleration of the entrance section or the exit section for handling work. Characteristic continuous processing line speed control method. 2. An acceleration rate of the central section speed is set to a predetermined value, and a speed in an entrance section or an exit section is accelerated after the processing at the non-stationary speed of the central section speed so that the central section speed is increased. 2. The speed control method for a continuous processing line according to claim 1, wherein the acceleration of the central section speed at the acceleration rate is started at a time when the speed coincides with the unsteady speed of the section.