JP2016093828A - Rolling control device, rolling control method and rolling control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suitably suppress a fluctuation in board thickness during switching, when control operation ends of tension control and board thickness control switch in a rolling state.SOLUTION: In a rolling machine for rolling a material-to-be-rolled by a roll pair, a control value of control based on a fluctuation in the tension of the material-to-be-rolled is suppressed to get small, when an operation end for controlling the tension of the material-to-be-rolled and an operation end for controlling plate thickness after rolling of the material-to-be-rolled switch depending a rolling state.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rolling control device, a rolling control method, and a rolling control program, and more particularly to selection of an operation end and feedback of a rolling mill having a plurality of operation ends and feedback.

  In a rolling mill that uses a tension reel for unwinding and winding the material to be rolled, the tension reel is operated by constant torque control (constant current control). As a problem in the case of constant torque control of the tension reel, if the tension on the entry side and exit side of the rolling mill fluctuates, the tension reel speed fluctuation occurs to suppress it, and the rolling mill entry side plate speed changes, It can be mentioned that the thickness variation on the delivery side occurs. As a countermeasure against this, in tension control using the tension reel speed as the operating end, the tension reel is operated with constant speed control, and a certain range of tension fluctuation is allowed in order to suppress variation in the outlet side plate thickness ( For example, see Patent Document 1).

  Further, in the tandem rolling mill, when the influence coefficient of the rolling mill greatly changes depending on the operation state, the control operation end with respect to the control state amount is changed in a timely manner (see, for example, Patent Document 2). In the tandem rolling mill, normally, the tension control between the stands using the lower stand pressure reduction as the control operation end and the delivery side plate thickness control using the front stand speed as the control operation end are performed. On the other hand, in the invention disclosed in Patent Document 2, according to the rolling state, the outlet side plate thickness control with the rear stand pressure reduction as the control operation end, and the tension control with the front stand speed as the control operation end are performed. This makes it possible to obtain the maximum effect of thickness control and tension control.

  Operating the unwinding-side tension reel and the winding-side tension reel with constant torque control (constant current control) causes fluctuations in the rolling mill entry speed and rolling mill exit speed that cause the rolling mill thickness variation. It becomes. This is because when the constant torque control is performed, the tension reel speed changes due to the inertia of the tension reel in order to keep the tension reel torque constant. As a result, the outlet side plate thickness variation occurs due to the constant mass flow rule.

  The most important factor for the material to be rolled by the rolling mill is the thickness accuracy of the exit side of the rolling mill, and the tension on the entry and exit sides of the rolling mill is important for the stability of operation, but the product thickness If it is to maintain, there is no problem in rolling operation even if it fluctuates somewhat. Based on this concept, the invention disclosed in Patent Document 1 corrects the tension deviation by giving priority to a constant tension reel speed with respect to a deviation from a preset tension value in a preset range. This prevents the tension reel speed fluctuation, and the tension reel is operated with constant speed control.

  In this case, it is sufficient that the tension deviation is within a preset range, but depending on the rolling state and the base material conditions, a case where the preset deviation exceeds the preset range occurs. In this case, since the tension reel speed is changed, the rolling mill entry side speed changes, and the exit side plate thickness fluctuation occurs.

  In some cases, the influence coefficient of the rolling mill changes depending on the rolling state, and tension control using the tension reel speed as the operating end and exit side thickness control using the roll gap of the rolling mill as the operating end become unstable. In such a case, the exit side plate thickness control with the current roll gap as the control operation end, the tension speed control when the tension reel is operated with constant speed control, and the tension reel when operated with constant torque control. It is difficult to control stably with constant tension torque control, and vibration of the rolling mill outlet side plate thickness will occur.

  On the other hand, based on the timing of the rolling operation, a method of performing tension control by a roll gap in a predetermined state and performing plate thickness control by speed control of a tension reel has been proposed (see, for example, Patent Document 3). ).

JP 2010-240661 A JP 2012-176428 A JP 2014-11629 A

  When using the technique disclosed in Patent Document 3, plate thickness control by roll gap and tension control by speed control (hereinafter referred to as “first control method”), and plate thickness by tension control and speed control by roll gap. There is a timing for switching between control (hereinafter referred to as “second control method”). If the actual tension value has a deviation from the target value at such timing, the control value after switching becomes excessively controlled, and a state in which the plate thickness fluctuation cannot be suppressed may occur. Such a problem is particularly likely to occur when the control method is switched in a state where the rolling speed is accelerated or decelerated.

  The problem to be solved in the present invention is to suitably suppress the thickness variation at the time of switching when the control operation ends of the tension control and the thickness control are switched in the rolling state.

  The present invention employs, for example, the configurations described in the claims. The present application includes a plurality of components that solve the above-described problems. For example, in a rolling mill that rolls a material to be rolled with a roll pair, an operation end and a material for controlling the tension of the material to be rolled. When the operation end for controlling the thickness of the rolled material after rolling is switched according to the rolling state, the control value based on the fluctuation of the tension of the material to be rolled is suppressed to be small when switching. It is characterized by.

  ADVANTAGE OF THE INVENTION According to this invention, when switching the control operation end of tension | tensile_strength control and plate | board thickness control in a rolling state, the board | plate thickness fluctuation | variation at the time of switching can be suppressed suitably. Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

It is a figure which shows the whole structure of the rolling mill and rolling control apparatus which concern on embodiment of this invention. It is a figure which shows the internal function of rolling-down board thickness control, speed board thickness control, speed tension control, and rolling-down tension control which concern on embodiment of this invention. It is a figure which shows the internal function of the control method selection apparatus which concerns on embodiment of this invention. It is a figure which shows the operation example of the optimal control method determination apparatus which concerns on embodiment of this invention. It is a figure which shows the operation example of the optimal control method determination apparatus which concerns on embodiment of this invention. It is a figure which shows the database of the control method which concerns on embodiment of this invention. It is a figure which shows the internal function of the control output selection apparatus which concerns on embodiment of this invention. It is a figure which shows the function of the entrance side TR speed command apparatus which concerns on embodiment of this invention. It is a figure which shows the deviation of the exit side plate | board thickness at the time of switching a control method at the time of acceleration / deceleration, and entrance side tension | tensile_strength. It is a figure which shows the operation | movement outline | summary of the entrance side tension deviation correction apparatus which concerns on embodiment of this invention. It is a figure which shows the operation | movement concept of the entrance side tension deviation correction apparatus which concerns on embodiment of this invention. It is a figure which shows the deviation of the exit side plate | board thickness and entrance side tension | tensile_strength at the time of switching a control method at the time of acceleration / deceleration by rolling control which concerns on embodiment of this invention. It is a figure which shows the function of the entrance side TR control apparatus which concerns on embodiment of this invention. It is a figure which shows the whole structure of the rolling control apparatus which concerns on a prior art. It is a figure which shows the example of the rolling phenomenon which concerns on a prior art. It is a figure which shows the example of the entrance side tension rolling phenomenon system based on a prior art. It is a figure which shows the example of the time series of each parameter which concerns on a prior art. It is a figure which shows the relationship between the control operation end and control state quantity of the single stand rolling mill which concerns on a prior art. It is a figure which shows the example of the single stand rolling phenomenon which concerns on a prior art. It is a figure which shows typically the cross response of the single stand rolling mill which concerns on a prior art. It is a figure which shows the example of a relationship between the control operation end of a single stand rolling mill, and a control state quantity. It is a figure which shows the relationship between the operation end which considered the cross term, and the control state quantity. It is a figure which shows the hardware constitutions of the rolling control apparatus which concerns on embodiment of this invention.

  Hereinafter, the details of the present invention will be described with reference to an example of a single stand rolling mill, which is a typical rolling mill that uses a tension reel for unwinding and winding the material to be rolled. FIG. 14 is a diagram showing a control configuration of the single stand rolling mill S100. The single stand rolling mill S100 is configured to supply and insert the material to be rolled u on the entry side of the rolling mill 1 with respect to the rolling direction of the rolling mill 1 that is a roll pair (indicated by an arrow in FIG. 14). It has a reel 2 (hereinafter referred to as entry side TR2), and has an exit side tension reel 3 (hereinafter referred to as exit side TR3) that takes up the material u rolled by the rolling mill 1 on the exit side. ing.

  The entry-side TR2 and the exit-side TR3 are each driven by an electric motor, and an entrance-side TR control device 5 and an exit-side TR control device 6 are installed as devices for driving and controlling the motor and the motor, respectively. With this configuration, rolling in the single stand rolling mill S100 is performed by rolling the material to be rolled u unwound from the entry side TR2 by the rolling mill 1 and then winding it at the exit side TR3.

  Here, the rolling mill 1 controls the thickness (product thickness) of the material to be rolled u after rolling by changing the roll gap, which is the distance between the upper work roll Rs1 and the lower work roll Rs2. A roll gap control device 7 for controlling the speed and a mill speed control device 4 for controlling the speed of the rolling mill 1 (the peripheral speeds of the upper and lower work rolls Rs1, Rs2) are installed. During rolling, a speed command is output from the rolling speed setting device 10 to the mill speed control device 4, and the mill speed control device 4 keeps the speed of the rolling mill 1 (the peripheral speeds of the upper and lower work rolls Rs1, Rs2) constant. The following control is performed. That is, the mill speed control device 4 functions as a rolling mill rotation control unit.

  On the entry side (the left side of the rolling mill 1 in FIG. 14) and the exit side (the right side of the rolling mill 1 in FIG. 14) of the rolling mill 1, rolling is performed stably and efficiently by applying tension to the material u. . It is the entry side tension setting device 11 and the exit side tension setting device 12 that calculate the tension required for this purpose. The entry side tension current conversion device 15 and the exit side tension current conversion device 16 are based on the entry side and exit side tension setting values calculated by the entry side tension setting device 11 and the exit side tension setting device 12. Current values for obtaining necessary motor torques of the respective motors on the entry side TR2 and the exit side TR3 in order to apply the set tension on the exit side to the material u to be rolled, and determine the respective current values on the entry side TR control device 5 and the output side TR control device 6.

  In the entry side TR control device 5 and the exit side TR control device 6, the current of the motor is controlled so as to become the given current, and the material to be rolled u is controlled by the respective motor torques given to the entry side TR2 and the exit side TR3. Is given a predetermined tension. The input side tension current conversion device 15 and the output side tension current conversion device 16 are current setting values (motor torque setting values) that become tension setting values based on models of the TR (tension reel) mechanical system and the TR (tension reel) control device. Value).

  However, since this control model includes an error, using the actual tension measured by the entry side tension meter 8 and the exit side tension meter 9 installed on the entry side and the exit side of the rolling mill 1, the entry side tension control 13. Further, the tension set value is corrected by the exit tension control 14 and applied to the entry tension current converter 15 and the exit tension current converter 16. As a result, the current values set by the input side tension current converter 15 and the output side tension current converter 16 to the input side TR control device 5 and the output side TR control device 6 are changed.

  Moreover, since the plate | board thickness of the to-be-rolled material u is important on product quality, plate | board thickness control is implemented. Specifically, the roll which is the space | interval between the rolls of the rolling mill 1 when the delivery side thickness control apparatus 18 controls the roll gap control apparatus 7 based on the actual board thickness detected in the delivery side thickness gauge 17. The gap is controlled to control the thickness of the exit side of the rolling mill 1 (the right side of the rolling mill 1 in FIG. 14).

  The output side TR3 and the input side TR2 used for winding and unwinding in a single stand rolling mill are controlled by constant torque control that makes constant the torque generated by each electric motor. Specifically, control for making the tension applied to the material u to be rolled constant by correcting the motor current command based on the actual tension detected by the entry side tension meter 8 and the exit side tension meter 9 is performed. ing. In addition, since the motor torque of each motor of the entrance side TR2 and the exit side TR3 is obtained by the motor current, the constant torque control may be set as the constant current control.

  When TR (tension reel) control is performed with constant torque control, there is a problem that the sheet thickness accuracy of the delivery side deteriorates due to interference with the sheet thickness control applied to the rolling mill. Since the entry side tension has a larger influence on the exit side plate thickness than the exit side tension, problems in the rolling mill 1 and the entry side TR2 will be described below.

  FIG. 15 is a conceptual diagram showing a rolling phenomenon between the entry side TR2 and the rolling mill 1 of the single stand rolling mill S100. As shown in FIG. 15, in the entry side TR2, it is determined from the motor torque 22, which is the output of the entry side TR control device 5, the entry side tension 24 (Tb), and the machine conditions (reel diameter D and reel gear ratio Gr). Is integrated, that is, the sum of the motor torque 22 and the tension torque 25 is integrated to determine the incoming TR (tension reel) speed 20. J is the moment of inertia (kg · m2) of the entry side TR2.

  In the rolling mill 1, a value obtained by integrating a predetermined coefficient (M / (M + Q)) as illustrated in the roll gap change amount 23 (= ΔS) and a predetermined tension as illustrated in the inlet side tension 24 of the rolling mill 1 are illustrated. Based on the value obtained by integrating the coefficients ((∂P / ∂Tb) / (M + Q)), the exit side plate thickness 26 is determined, and from the determined exit side plate thickness 26, the rolling mill entrance side speed 21 is determined according to a constant mass flow rule. It is determined. The difference between the rolling mill entry side speed 21 and the entry side TR speed 20 is integrated to obtain the entry side tension 24. In FIG. 15, M is the mill constant M (kN / m), Q is the plastic constant Q (kN / m), and (∂P / ∂Tb) / (M + Q) is the input side tension Tb. It is an influence coefficient (kb) of the fluctuation of the rolling load P (kN) due to the fluctuation to the outlet side plate thickness.

In the rolling mill 1, there is a constant mass flow law as a basic law. This is because the material to be rolled u on the entrance side of the rolling mill 1 (left side of the rolling mill 1 shown in FIG. 14) and the exit side of the rolling mill 1 (right side of the rolling mill 1 shown in FIG. 14) are continuous. 1).
H ・ Ve = h ・ Vo (1)
H: Incoming plate thickness h of rolling mill 1: Outgoing plate thickness Ve of rolling mill 1 Ve: Incoming plate speed Vo of rolling mill 1 Vo: Outgoing plate speed of rolling mill 1

  From equation (1) of the constant mass flow rule, when the inlet side plate thickness is constant, it means that the outlet side plate thickness changes when the inlet side plate speed changes. In the case of a single stand rolling mill (one rolling mill 1 shown in FIG. 14), the entry side plate speed is the entry side TR speed. The entry side TR2 changes the entry side TR speed 20 so that the tension torque 25 matches the electric motor torque 22. This change is made by the inertia of the entry side TR2, the rolling mill 1, and the rolling phenomenon. There is no control means to suppress the change of

  Therefore, in the rolling mill 1, when the ΔS of the roll gap change amount 23 is operated in order to make the outlet side thickness (the thickness of the material u to be rolled out on the outlet side of the rolling mill 1) constant by controlling the thickness, rolling is performed accordingly. The machine entry side speed 21 (the conveyance speed of the material to be rolled u on the entry side of the rolling mill 1) changes, and a deviation ΔTb of the entry side tension 24 occurs. In order to suppress this, the entry side TR speed 20 fluctuates, and this fluctuation causes an exit side plate thickness fluctuation. The entry side tension suppression system 27 performed by the entry side TR2 may have a large time constant depending on the rolling conditions, and may cause variation in the exit side plate thickness having a large undulation.

  The entry side tension 24 is also suppressed by a rolling phenomenon. When the entry side tension 24 fluctuates, the rolling load P of the rolling mill 1 changes, and the rolling mill entry side speed 21 fluctuates accordingly. The entry side tension 24 also varies depending on the entry side tension rolling phenomenon system 28. Since the response of the entry side tension rolling phenomenon system 28 is much faster than that of the entry side tension suppression system 27, the entry side rolling phenomenon shown in FIG. 15 can be converted as shown in FIG.

  From FIG. 16, the roll gap change amount 23 (= ΔS) of the rolling mill 1 appears as a deviation ΔTb of the entry side tension 24 in the same phase, and the entry side TR speed 20 in the state where it is integrated at the entry side TR2. It can be seen that changes. Accordingly, the relationship between the roll gap change amount 23 (= ΔS) and the deviation ΔTb of the inlet side tension 24, the change of the inlet side TR speed 20, and the change of the outlet side plate thickness are as shown in FIG. FIG. 17 is a diagram illustrating the relationship among the roll gap change amount 23, the entry side tension 24 (Tb), the entry side TR speed 20, and the exit side plate thickness.

  As shown in FIG. 17, when the roll gap change amount 23 changes, the entry-side speed of the rolling mill 1 changes and the entry-side tension 24 changes. As the input side tension 24 changes, the input side TR2 performs constant torque control, so the input side TR speed 20 changes due to the inertia of the input side TR. When the inlet TR speed 20 fluctuates, the outlet plate thickness fluctuations are generated according to the mass flow constant law shown in the above equation (1). When the outlet side plate thickness fluctuation occurs, the outlet side plate thickness control device 18 operates the roll gap change amount 23 to keep the outlet side plate thickness constant. When these series of operations are continued, the outlet side plate thickness vibrates as shown in FIG.

  Actually, since the delivery side thickness gauge 17 is installed at a location away from the rolling mill 1, there is a delay time until the delivery side thickness is detected by the delivery side thickness control device 18, but the oscillation of the delivery side thickness is present. If the delay time is sufficiently short with respect to the period, it can be ignored.

  In order to prevent such oscillation of the exit side plate thickness, while controlling to maintain the tension between the tension reel and the rolling mill at a desired value, the deviation from the tension setting value within a preset range is performed. In the method, priority is given to the constant tension reel speed, and the tension reel speed fluctuation is suppressed by not correcting the tension deviation. However, in this method, there is a case where fluctuations in the sheet thickness on the outlet side of the rolling mill cannot be suppressed by suppressing changes in the tension reel speed.

  In a rolling mill, there are two control operation ends such as a roll gap and a roll speed, and two control state quantities such as an exit side plate thickness of the rolling mill and an entry side (or exit side) tension of the rolling mill. When two control operation ends are operated, the control state quantity changes by affecting each of the two control state quantities. FIG. 17 is a diagram showing the relationship between the control operation end and the control state quantity in the case of a single stand rolling mill. The rolling phenomenon of the single stand rolling mill is as shown in FIG. 18, and FIG. 19 conceptually describes this phenomenon.

  In the case of the single stand rolling mill 1, the control operation ends are a roll gap change amount 23 and an entry side TR speed 20. Further, the control state quantities are the outlet side plate thickness 26 and the inlet side tension 24 of the rolling mill. When the roll gap change amount 23 is changed, changes in the exit side plate thickness 26 due to the (roll gap → exit side plate thickness) influence coefficient 503 and the entry side tension 24 due to the (roll gap → enter side tension) influence coefficient 501 occur. In addition, when the entry side TR speed 20 is changed, the entry side tension 24 based on the (input side TR speed → input side tension) influence coefficient 502, and the exit side plate thickness 26 based on the (input side TR speed → exit side plate thickness) influence coefficient 504. Change occurs.

  In the single stand rolling mill 1, as shown in FIG. 19, the exit side plate thickness 26 is controlled by the exit side plate thickness control device 18 changing the roll gap change amount 23. Further, the entry side tension 24 is controlled by changing the entry side TR speed 20 by the entry side tension suppressing system 27 as shown in FIG.

  (Roll gap → exit side plate thickness) influence coefficient 503 and (input side TR speed → input side tension) influence coefficient 502 are (roll gap → input side tension) influence coefficient 501 and (input side TR speed → exit side plate thickness) influence. If the coefficient is sufficiently larger than the coefficient 504, there is no problem with this control configuration, but as shown in the known example 2, the influence coefficient 503 (roll gap → exit side plate thickness) and (input side TR speed → input side tension) are shown. ) If the influence coefficient 502 becomes smaller than the influence coefficient 501 (the roll gap → input side tension) influence coefficient 501 and the influence coefficient 504 (the input side TR speed → exit side plate thickness), there arises a problem that the control is not stably performed. To do.

  In such a state, even if the plate thickness control device 18 operates the roll gap change amount 23 to control the exit side plate thickness 26, the entry side tension 24 fluctuates greatly to control it. When the entry side tension suppression system 27 changes the entry side TR speed 20, the exit side plate thickness 26 varies greatly accordingly. When the delivery side plate thickness changes, the plate thickness controller 18 operates the roll gap change amount 23. As a result, the exit side plate thickness 26, the entry side tension 24, the entry side TR speed 20, and the roll gap change amount 23 have the same cycle. The state that vibrates will occur.

  The entrance-side rolling phenomenon of the single stand rolling mill is as shown in FIG. The entry side tension suppression system 27 by the entry side TR2 is removed, the entry side TR speed 20 and the roll gap change amount 23 are used as control operation ends, and the exit side plate thickness 26 and the entry side tension 24 are created as control state quantities. A block diagram similar to FIG. 16 is shown in FIG. As in the case of conversion from FIG. 15 to FIG. 16, the entry side tension rolling phenomenon system 28 is collectively used as the entry side tension influence coefficient 101. In FIG. 15, the first-order lag time constant Tr that is omitted because the response time is sufficiently short compared with the entry side tension suppression system 27 by the entry side TR <b> 2 is left in FIG. 16. From FIG. 16, 111, 112, 113, and 114 of FIG. 19 are obtained as corresponding to the influence coefficients 501, 502, 503, and 504 in FIG.

  Here, Ve is the entry side TR speed 20, and h is the exit side plate thickness 26 of the rolling mill. Therefore, if the exit side plate thickness 26 is thin and the entry side TR rate 20 is high, (input side TR rate → outside plate thickness). It can be seen that the influence coefficient 114 and the (incoming TR speed → incoming tension) influence coefficient 112 become smaller. Further, the first-order lag time constant Tr included in the entry-side tension influence coefficient 101 becomes small. Therefore, the influence coefficient 113 (roll gap → exit side plate thickness) becomes small. Further, the response coefficient 111 (roll gap → entry side tension) influence coefficient 111 becomes faster. That is, if the exit side plate thickness 26 is thin and the entry side TR speed 20 is fast, the exit side plate thickness 26 of the rolling mill is unlikely to change during the operation of changing the roll gap 23, and the entry side tension is likely to change. That is, the (roll gap → entry side tension) influence coefficient 111 is larger than the (roll gap → exit side plate thickness) influence coefficient 113. Further, when the entry side TR speed 20 is operated, the entry side tension 24 and the exit side plate thickness 26 are hardly changed in the same manner.

  The entry side tension includes a rolling phenomenon term kb. The kb also changes according to the rolling speed and the exit side plate thickness, but when the kb increases, the (input side TR speed → input side tension) influence coefficient 112 is compared with the (input side TR speed → exit side plate thickness) influence coefficient 114. And get smaller.

  From the above, when the outlet side plate thickness 26 is thin and the inlet side TR speed 20 is increased, the (roll gap → outside plate thickness) influence coefficient 113 becomes smaller than the (roll gap → inlet side tension) influence coefficient 111. It can be seen that there is a case where the influence coefficient 112 (input side TR speed → input side tension) becomes smaller than the influence coefficient 114 (input side TR speed → outside plate thickness). In such a case, if the outlet side thickness 26 is controlled by the plate thickness controller 18 and the inlet side tension 24 is controlled by the inlet side tension suppression system 27 as shown in FIG. It becomes impossible to control.

  In such a case, as shown in FIG. 22, the speed plate thickness control device 50 that controls the outlet side plate thickness 26 at the inlet side TR speed 20 and the inlet side tension 24 are controlled by the roll gap change amount 23. By applying the rolling tension control 61, the outlet side plate thickness 26 and the inlet side tension 24 can be stably controlled. In order to realize this, it is necessary to change the input side TR2 that has been operated in the conventional constant torque control (constant current control) to the operation in the constant speed control.

  Even when the response of the entry side tension suppression system 27 deteriorates, it is necessary to operate the entry side TR2 with constant speed control. The entry side tension suppression system 27 in FIG. 16 becomes a first-order lag system with a time constant Tq by equivalent conversion. Here, Tq is proportional to the incoming TR speed 20, inversely proportional to the outlet thickness 26 of the rolling mill, and proportional to the rolling phenomenon term kb. Accordingly, when the rolling phenomenon term kb is increased, the time constant Tq of the entry side tension suppression system 27 is increased, and the response of the entry side tension suppression system 27 is deteriorated. In this case, since the influence coefficient 111 (roll gap → entrance tension) in FIG. 21 does not increase, the plate thickness control by the conventional roll gap change amount 23 and the tension control by the entrance tension suppression system 27 are stable. It is thought that it can be controlled.

In rolling equipment, various materials to be rolled are rolled to various plate thicknesses, and the rolling speed is also various. Therefore, depending on the rolling state, the following three types of cases where the exit side plate thickness and the entrance side tension control can be stably performed occur.
A) Plate thickness control for manipulating the roll gap, and tension control by the entry side tension suppression system of the entry side TR operated with constant torque control.
B) Plate thickness control for manipulating the roll gap, and speed tension control for manipulating the speed of the entry side TR operated with constant speed control.
C) Rolling tension control for manipulating the roll gap, and speed plate thickness control for manipulating the speed of the entry side TR operated with constant speed control.

In order to stably carry out sheet thickness control and tension control of the rolling mill, it is necessary to switch and use the above three types of control in accordance with the rolling state. FIG. 1 shows a control configuration of a single stand rolling mill according to the present embodiment for realizing this. Using the exit side thickness deviation Δh detected by the exit side thickness gauge 17, an operation command ΔΔS _AGC for the roll gap is generated by the rolling plate thickness control 61, and an operation command ΔΔV for the entry side TR speed is generated by the speed plate thickness control 62. _AGC is generated. Further, using the deviation (entrance tension deviation) ΔTb between the actual entry side tension measured by the entry side tension meter 8 and the entry side tension setting set by the entry side tension setting device 11. , the speed tension control 63 generates an operation command DerutaderutaV _ATR to entry side TR rate, the pressure tension control 64 generates an operation command Derutaderutaesu _ATR to the roll gap.

  When the entry side TR2 is operated with constant torque control, the entry side tension set value by the entry side tension setting device 11 is added to the entry side tension according to the deviation between the entry side tension result and the entry side tension set value. The control signal from the input side tension control 13 for manipulating the set value is converted into a current command to the input side TR2 by the input side tension current conversion device 15, and the current command to the input side TR control device 66 is converted. Create

  The control method selection device 70 selects, according to the rolling state, whether the above-described A), B), or C) control method can be applied to reduce the most variation in the exit side plate thickness and the entry side tension, Based on the selection result, a roll gap operation command is output to the roll gap control device 7. When operating the incoming TR speed, a speed operation command is output to the incoming TR speed command device 65. In the incoming TR speed command device 65, an incoming TR speed command is created from the incoming TR reference speed output from the reference speed setting device 19 and the incoming TR speed change amount from the control method selection device 70. To the side TR controller 66.

  The incoming TR control device 66 has an operation mode in which constant torque control (current constant control) is performed in response to a current command and an operation mode in which constant speed control is performed in response to a speed command. Change operation according to the command.

  FIG. 2 shows an example of a block diagram of the rolling plate thickness control 61, the velocity plate thickness control 62, the speed tension control 63, and the rolling tension control 64. These are examples of each control configuration, and the control system can be configured using other methods. For example, in the example of FIG. 2, each control system is integral control (I control), but may be proportional integral (PI control) or differential proportional integral control (PID control).

Reduction gauge control 61, output as input left side thickness deviation Δh ₌ h _{fb -h ref} is the difference between the delivery thickness set value _{h ref} out with plate thickness performance _{h fb,} adjusted to side thickness deviation output is input It consists of integral control (I control) that integrates the gain and the conversion gain from the outlet side plate thickness deviation to the roll gap. The difference between the output after integration and the previous value is taken as the control output ΔΔS _AGC . Further, the speed plate thickness control 62 receives the output side plate thickness deviation Δh, and integrates the input output side plate thickness deviation multiplied by the adjustment gain and the conversion gain from the output side plate thickness deviation to the input side speed. (I control). Taking the deviation between the integrated output and the previous value, the following equation (15) or (16) is used as the control output.


Here, M is a mill constant of the rolling mill, and Q is a plastic constant of the material to be rolled. The speed plate thickness control command is output as a speed change ratio with respect to the set speed.

Reduction tension control 64 receives as input is the difference between the entry side tension actual _{T Bfbb} and entry side tension set value _{T bref} entry side tension deviation ΔTb _{= T} bfbb _{-T bref,} adjusted to the input entry side tension deviation .DELTA.Tb It consists of integral control (I control) that integrates the gain and the conversion gain to the roll gap multiplied by the input side tension deviation ΔTb. The difference between the output after integration and the previous value is taken as the control output ΔΔS _ATR .

The speed tension control 63 receives the input side tension deviation ΔTb, and integrates the input side tension deviation ΔTb multiplied by the adjustment gain and the conversion gain from the input side tension deviation ΔTb to the input side speed. It consists of control (I control). Taking the deviation between the integrated output and the previous value, the following equation (3) is used as the control output.

  FIG. 3 shows an outline of the control method selection device 70. The control method selection device 70 includes an optimal control method determination device 71 and a control output selection device 72. The optimum control method determining device 71 determines which of the above-described control methods A), B), and C) is used for control, and the control output selecting device 72 uses the reduction plate thickness control 61, speed plate, and the like. The output of the thickness control 62, speed tension control 63, or rolling tension control 64 is selected and a control command is output to the roll gap control device 7, the incoming TR speed command device 65, and the incoming TR control device 66. To do. That is, the optimal control method determination device 71 functions as a control mode determination unit.

  FIG. 4 shows an outline of the operation of the optimum control method determination device 71. Here, when the (roll gap → entrance tension) influence coefficient 111 is large, the tension control by reduction and the plate thickness control by the reel speed are performed using the control method C), and the tension of the entrance tension suppression system 27 is corrected. When the constant is large, the sheet thickness control by reduction and the entry side tension control for operating the TR speed are performed by the control method B). In other cases, the conventional control method A) is selected.

  Which of the three control methods is selected is determined by the following. Since the optimum control method is considered to change depending on the steel type of the material to be rolled, the exit side plate thickness, and the rolling speed, if the steel type or the exit side plate thickness changes, the rolling speed is divided into three stages of low speed, medium speed, and high speed, When the corresponding rolling speed is reached during rolling, the roll gap is changed stepwise to examine changes in entry side tension and exit side plate thickness. In this case, if the roll gap change amount is changed so as not to affect the product quality of the material to be rolled, it can be implemented even during the rolling of the product material. When the roll gap is changed stepwise, the above-described control method A) is selected.

  In the present embodiment, as shown in FIG. 4, the rolling speed is changed stepwise in the order of low speed, medium speed, and high speed. This is executed to select one of the three control methods described above. However, even when the rolling operation is actually started, the rolling speed is increased stepwise as shown in FIG. Therefore, the operation as shown in FIG. 4 can be performed in conjunction with a normal rolling operation, and can be performed without reducing the productivity.

  Measure the entry side tension fluctuation amount and the exit side plate thickness fluctuation amount immediately after changing the roll gap stepwise, and the (roll gap → entry side tension) influence coefficient 114 and the (roll gap → exit side plate thickness) influence coefficient 112 Determine which is larger. The response time of the entry side tension suppression system 27 is determined from the change in the entry side tension when the roll gap is operated stepwise.

  For example, as shown in FIG. 4, low speed, medium speed, and high speed regions are determined according to the rolling speed. In this determination method, the maximum speed may be divided into three equal parts or divided according to other appropriate criteria. As the rolling speed enters these regions, a stepped disturbance is added to the roll gap. By applying a step-like disturbance, the entry side tension and the exit side plate thickness change.

  Next, as shown in FIG. 5, parameters dTb, dh, and Tbr are obtained from the results of entry side tension and exit side plate thickness deviation. These parameters can be obtained by signal processing from the fluctuation state of the actual value in the time direction. The control method A), the control method B), and the control method C) are selected from the magnitude relationship among the obtained parameters dTb, dh, and Tbr.

  When selecting each of the control method A), the control method B), and the control method C), as shown in FIG. 5, the values calculated based on the parameters dTb, dh, and Tbr described above are compared with a predetermined threshold value. Judgment. For example, if the value calculated by (dh / href) / (dTb / Tbref) is equal to or less than the control method C) selection value that is a predetermined threshold value, the control method C) is selected. Also, if Tbr is equal to or greater than the control method B) selection value that is a predetermined threshold value, control method B) is selected. The control method C) selection value and the control method B) selection value can be obtained and set in advance by past performance values, rolling mill simulations, or the like.

  This optimal control method selection process is changed to a step-like change at low speed, medium speed, and high speed. Step change 2. 2. Step change 3. In the case shown in FIG. 5, the result is that the control method A) for the low speed, the control method B) for the medium speed, and the control method C) for the high speed are selected as the optimal control methods.

  The control method selection device 70 executes such an optimum control method determination procedure and switches the control method to the obtained optimum control method. In this case, the control method A), the control method B), and the control method C) may not be switched during the rolling operation because the control method of the entry side TR is different. In that case, the rolling operation may be continued by the control method A), and the control method may be switched when a rolled material having the same steel type and the same sheet width comes next time. The optimum control method obtained is recorded in the database using the steel type, exit side plate thickness and rolling speed of the material to be rolled as search conditions, and when the same type of material to be rolled is rolled next time, the optimum control method recorded in the database. Control according to.

  An example of a database record is shown in FIG. Depending on the rolling equipment, there is a case where the switching between the control method A), the control method B) and the control method C) cannot be performed during the rolling operation, but it is also possible to use the control method B) instead of the control method A). . In this way, in the case of a material to be rolled that is control method A) at low speed but optimal control method C) at high speed, it is possible to select all of control materials by selecting control method B) at low speed and control method C) at high speed. Stable and highly accurate rolling is possible in the speed range.

  The method described above is an example of the procedure for determining the optimum control method, and other methods can be used. For example, it is possible to obtain the influence coefficient shown in FIG. 21 numerically from the rolling record using a rolling phenomenon model, and to select the optimum control method from the magnitude relationship.

  FIG. 7 shows an outline of the operation of the control output selection device 72. In the control output selection device 72, the roll reduction plate thickness control 61, the velocity plate thickness control 62, the velocity tension control 63, the output from the reduction tension control 64, and the control method selection result from the optimum control method determination device 71 are input. A control command is output to the gap control device 7, the incoming TR speed command device 65, and the incoming TR control device 66.

  As shown in FIG. 7, in the control output selection device 72, the outputs from the rolling plate thickness control 61, the speed plate thickness control 62, the speed tension control 63, and the rolling tension control 64 are respectively output to the gain controllers 73, 74, 75, 76 is input. The gain controllers 73 to 76 are signal adjusting units that apply gains to the outputs of the rolling plate thickness control 61, the speed plate thickness control 62, the speed tension control 63, and the rolling tension control 64 and output the gains. The gains of the gain controllers 73 to 76 are adjusted based on the control method selection result from the optimum control method determination device 71.

  When the control method A) is selected, the output from the rolling plate thickness control 61 is integrated and output to the roll gap control device 7. In addition, a constant torque control mode selection is output to the incoming TR control device 66. Therefore, the gains of the gain controllers 74 to 76 are set to zero and the gain of the gain controller 73 is adjusted according to the control method selection result by the optimum control method determining device 71, and the output from the rolling plate thickness control 61 is integrated. The unit 77 is set to be integrated. Further, according to the control method selection result by the optimum control method determination device 71, the constant torque control mode selection is output to the ingress TR control device 66. In this case, the entry side TR control device 66 functions as a tension reel torque control unit.

  When the control method B) is selected, the output from the rolling plate thickness control 61 is integrated and output to the roll gap control device 7, and the output from the speed tension control 63 is integrated to perform the input TR speed command device. Output to 65. Therefore, the gains of the gain controllers 74 and 75 are set to zero and the gains of the gain controllers 73 and 76 are adjusted based on the control method selection result by the optimum control method determination device 71, and the output from the rolling plate thickness control 61 is It is set so that the integration processing unit 77 performs integration processing and the output from the speed tension control 63 is integrated by the integration processing unit 78.

  When the control method C) is selected, the output from the speed plate thickness control 62 is integrated and output to the input TR speed command device 65, and the output from the rolling tension control 64 is integrated to roll the control device. 7 is output. Therefore, the gains of the gain controllers 73 and 76 are set to zero and the gains of the gain controllers 74 and 75 are adjusted according to the control method selection result by the optimum control method determining device 71, and the output from the rolling tension control 64 is integrated. Integration processing is performed by the processing unit 77 and the output from the speed plate thickness control 62 is set to be integrated by the integration processing unit 78.

  That is, the control path connected to the integration processing unit 77 and the roll gap control device 7 functions as a roll gap control unit. Further, the control path connected to the integration processing unit 78 and the incoming TR speed command device 65 functions as a speed control unit.

By using the method as shown in FIG. 7, it is possible to switch between the control methods A), B), and C) even during the rolling operation, for example, depending on the rolling speed. In the entry side TR speed command device 65, as shown in FIG. 8, the reference speed setting device 19 uses the rolling mill input side from the rolling mill speed V _MILL determined by the rolling speed setting device 10 by an operator's manual operation. Using the control command from the control method selection device 70 using the input side TR speed V _ETR created in consideration of the reverse speed b, the _input side TR speed command V _ETRref is generated and the _input side TR control device 66 Output.

  By using the method as shown in FIG. 7, the roll gap command of the rolling mill 1 and the speed command of the entry side TR2 can be smoothly changed even when the control operation ends of the sheet thickness control and the tension control are switched. However, when the control operation end is switched, there is a case where the variation in the outlet side plate thickness cannot be suppressed due to the influence of the inlet side tension control. The operation method of the single stand rolling mill which is the object of this example is shown in FIG.

  The rolling of the rolling mill is accelerated, rolled at a high speed, and finally decelerated to complete the rolling of one material to be rolled (coil). Therefore, switching from control method B) to control method C) occurs during acceleration, and switching from control method C) to control method B) occurs during deceleration. For example, when the rolling mill decelerates, switching from the control method C) to the control method B) occurs. As a result, the control of the exit side plate thickness using the speed of the entrance side TR <b> 2 is switched to the control by the roll gap of the rolling mill 1. Similarly, what controlled the entrance side tension | tensile_strength using the roll gap of the rolling mill 1 switches to control using the speed of entrance side TR2.

  When the roll speed (rolling speed) of the rolling mill increases (accelerates), as the rolling phenomenon, the exit side plate thickness decreases, and accordingly, the entrance side plate speed decreases with a constant mass flow law, and the entrance side tension decreases. In order to suppress this, in the control method B), exit side plate thickness control using the roll gap of the rolling mill 1 and entry side tension control using the speed of the entry side TR2 are performed.

  Here, the entry side tension control operates to reduce (decelerate) the speed of the entry side TR2 because the entry side tension becomes small. Decreasing the speed of the entry side TR2 results in a decrease in the exit side plate thickness. The exit side plate thickness control attempts to maintain the exit side plate thickness by opening the roll gap of the rolling mill 1. At this time, the exit side plate thickness control needs to control the exit side plate thickness reduction due to acceleration of the rolling mill 1 and the exit side plate thickness reduction due to the entry side tension control operating the speed of the entrance side TR2.

  In this case, the outlet side plate thickness control opens the roll gap of the rolling mill. As a result, the entry side tension rises, so that it operates in a good direction for entry side tension control. Therefore, in the state of the control method B), the entry side tension and the exit side plate thickness can be controlled well.

  In this state, when switching to the control method C), the entry side tension control operates the roll gap of the rolling mill 1, and the exit side plate thickness control operates the speed of the entry side TR2. In this case, when the entry side TR2 is accelerated, the entry side tension is lowered, so that the roll gap of the rolling mill is narrowed by the entry side tension control. As a result, the outlet side plate thickness decreases, and the speed of the inlet side TR2 increases by the outlet side plate thickness control.

  Increasing the speed of the entry side TR2 lowers the entry side tension. Therefore, the entry side tension control is performed by reducing the entry side tension as a rolling phenomenon and the sheet thickness control is performed by operating the speed of the entry side TR2. Both side tension drops need to be controlled. In this case, the entry side tension control attempts to increase the entry side tension by opening the roll gap of the rolling mill. However, if the influence coefficient of the roll gap change of the rolling mill 1 on the entry side tension is small, the exit side plate thickness varies in a state where the entry side tension cannot be sufficiently controlled. For example, the roll gap is excessively opened and the exit side plate thickness is increased.

  Similarly to the above, when the roll speed (rolling speed) of the rolling mill decreases (decreases), as the rolling phenomenon, the exit side plate thickness increases, and the entrance side plate speed increases according to the mass flow constant law. Tension increases. In order to suppress this, during control method C), tension control using the roll gap of the rolling mill and plate thickness control using the speed of the entry side TR2 are performed. Here, in the exit side plate thickness control, the exit side plate thickness is increased, so that the speed of the entry side TR2 is reduced (decelerated).

  Decreasing the speed of the entry side TR2 results in an increase in entry side tension. Therefore, the entry side tension during deceleration increases due to the rolling phenomenon and due to the exit side plate thickness control operating the speed of the entry side TR2. The entry side tension control operates the roll gap of the rolling mill 1, but if the influence coefficient from the roll gap of the rolling mill 1 to the entry side tension is reduced, the increase of the entry side tension cannot be controlled, and the entry side tension is controlled. May be larger than the set tension.

  In this state, when switching to the control method B), the input side tension control operates the speed of the input side TR2, and the output side plate thickness control operates the roll gap of the rolling mill 1. In this case, since the entry side tension is larger than the set value, the entry side tension control increases the speed of the entry side TR2, and as a result, the exit side plate thickness deviation increases. The outlet side thickness control operates the roll gap of the rolling mill 1 (press close) to suppress the fluctuation of the outlet side plate thickness, but the inlet side tension control operates so that the inlet side tension is reduced and removed. However, the plate thickness deviation is not eliminated by the mass flow constant law until the speed of the entry side TR2 is restored.

  From the above, in the state where the influence coefficient from the roll gap of the rolling mill 1 to the entry side tension is sufficiently large, unless the control method B) and the control method C) are switched, the entry side tension cannot be controlled sufficiently and Side plate thickness fluctuations may occur. Therefore, when switching between the control method B) and the control method C), it is necessary to carry out while the influence coefficient from the roll gap of the rolling mill to the entry side tension is sufficiently large. However, since the reason for using the control method C) is to remove the plate thickness fluctuation caused by the speed fluctuation of the entry side TR2, it is required to use the control method C) until the speed is as low as possible.

  The lower part of FIG. 9 shows the state of the exit side thickness deviation and the entrance side tension when the above problem occurs. At the time of acceleration, the outlet side plate thickness fluctuation occurs immediately after switching from the control method B) to the control method C) and at the time of deceleration immediately after switching from the control method C) to the control method B). On the other hand, the above-mentioned phenomenon can be avoided by not performing switching between the control method B) and the control method C) during acceleration / deceleration, but performing it during rolling at a constant speed. However, there is a problem that the operation at a constant speed is necessary until the control is stabilized, and the operation efficiency is deteriorated.

  The delivery side plate thickness accuracy is important in terms of the quality of the material to be rolled, but there is no problem in operation stability as long as the exit side plate thickness is stable even if the entry side tension varies slightly. Therefore, by correcting the operation of the entrance side tension control, it is possible to maintain the exit side plate thickness accuracy even when the influence coefficient from the roll gap of the rolling mill to the entrance side tension is not sufficiently large. Necessary. Further, even in this case, if the entry side tension deviates from a certain range, plate breakage, meandering, etc. occur. Therefore, the entry side tension needs to be within an allowable value that is a predetermined range from the operational stability. .

  Therefore, in the rolling control device according to the present embodiment, an entry side tension deviation correction device 91 is provided as shown in FIG. FIG. 10 is a diagram showing an outline of the operation of the entry-side tension deviation correction apparatus. As shown in FIG. 10, the entry-side tension deviation correction device 91 includes an upper limit allowable value setting device 92, a lower limit allowable value setting device 93, and a deviation correction unit 94. Then, the deviation correction unit 94 enters the input side tension deviation value if it is within the range of the upper limit value and the lower limit value set by the upper limit allowable value setting device 92 and the lower limit allowable value setting device 93, respectively. The side tension deviation is corrected to zero and output. Thereby, the value of the input side tension deviation input to the speed tension control 63 and the reduction tension control 64 is corrected.

  As a result, even if an entry-side tension deviation occurs, the speed-tension control 63 and the rolling-down tension control 64 appear to have no deviation, and the tension control by the entry-side TR speed command device 65 is performed. Operation is suppressed. That is, the entry-side tension deviation correction device 91 functions as a tension control suppressing unit. Further, the upper limit allowable value setting device 92 and the lower limit allowable value setting device 93 function as a tension control suppression setting unit that specifies the allowable value of the tension deviation. Such an operation by the entry side tension deviation correcting device 91 is performed immediately after switching from the control method B) to the control method C) and immediately after switching from the control method C) to the control method B). Thereby, the problems as described above can be solved.

FIG. 11 is a diagram illustrating an operation concept of the entry-side tension deviation correction device 91. In FIG. 11, the target value for the tension setting is indicated by a thin broken line, and the allowable values set by the upper limit allowable value setting device 92 and the lower limit allowable value setting device 93 are indicated by a thick broken line. As shown in FIG. 11, the upper limit allowable value setting device 92 and the lower limit allowable value setting device 93 are switched from the control method B) to the control method C) or from the control method C) to the control method B). At the timing t ₀ , the upper limit allowable value ΔT _bmax and the lower limit allowable value ΔT _bmin are set for the deviation correction unit 94, respectively. The values of the upper limit allowable value ΔT _bmax and the lower limit allowable value ΔT _bmin are the allowable values of the _input side tension deviation, that is, the dead band of the input side tension control.

Thereafter, the deviation correction unit 94 decreases the upper limit allowable value ΔT _bmax and the lower limit allowable value ΔT _bmin with the passage of time. Thereby, the width | variety of the allowable entrance side tension deviation becomes small with progress of time. Then, the upper limit allowable value [Delta] T _bmax at timing t _1, the lower limit permissible value [Delta] T _bmin is zero, the state returns to the state where normal tension control from a state in which tension control is suppressed by the entering-side TR speed command device 65 is performed. A few seconds duration timing t ₁ from time t _0, for example to 10 seconds, the material and the rolling speed of the rolling stock, the optimum period by other conditions reduction ratio, etc. are different.

  FIG. 12 is a diagram illustrating a control state when processing by the entry-side tension deviation correction device 91 as illustrated in FIGS. 10 and 11 is performed, and corresponds to FIG. 9. By suppressing the entry side tension deviation at the time of switching between the control methods B) and C), as shown in FIG. 12, the variation in the exit side plate thickness deviation can be reduced as compared with the case of FIG.

The upper limit allowable value setting device 92 and the lower limit allowable value setting device 93 are based on the incoming TR reference speed output from the reference speed setting device 19 and refer to the optimum control method database as described in FIGS. , The switching timing of the control method B) and the control method C), and during the acceleration and deceleration of the rolling mill are recognized. Then, based on the recognition result, the upper limit allowable value ΔT _bmax and the lower limit allowable value ΔT _bmin shown in FIG. 11 are calculated and set in the deviation correction unit 94.

The setting of the upper limit allowable value ΔT _bmax and the lower limit allowable value ΔT _bmin by the upper limit allowable value setting device 92 and the lower limit allowable value setting device 93 is based on the input TR reference speed output from the reference speed setting device 19 described above. Not only the mode to be performed but also other methods can be used. For example, when the optimum control method determination device 71 of the control method selection device 70 switches the control method, the upper limit allowable value setting device 92 and the lower limit allowable value setting device 93 are respectively set to the upper limit allowable value ΔT _bmax and the lower limit allowable value ΔT _bmin. May be instructed.

The deviation correction unit 94 adjusts the upper limit allowable value ΔT _bmax and the lower limit allowable value ΔT _bmin as time passes, as shown in FIG. Then, the deviation correction unit 94 corrects a value obtained by subtracting the upper limit allowable value ΔT _bmax from the input side tension deviation if the input value of the input side tension deviation is larger than the upper limit allowable value ΔT _bmax at the time of input. Output as the subsequent entry tension deviation.

If the input entry tension deviation value is smaller than the upper limit allowable value ΔT _bmax at the time of input and greater than the lower limit allowable value ΔT _bmin , zero is output as the corrected entry tension deviation. Further, if the value of the input entry side tension deviation is smaller than the lower limit allowable value ΔT _bmin at the time of input, the value obtained by subtracting the lower limit allowable value ΔT _bmin from the input entry side tension deviation is corrected. Output as.

FIG. 13 shows an outline of the entry side TR control device 66. The input TR speed command V _ETRref from the input TR speed command device 65, the current command I _ETRset from the input tension current converter, and the constant torque control mode from the control method selection device 70 are input to the input TR2. The current is output. Here, the entry side TR2 is constituted by a TR mechanical device and an electric motor for moving the TR, and the current to the entry side TR2 indicates a current to the electric motor.

Inlet side TR control device 66 flows to the P control 661 and I control 662, the current command _{I ETRref} and entry side TR2 of motor created to create a current command to match the speed command _{V ETRref} and speed actual _{V ETRfb} The current control 663 is configured to control the current I _ETRfb so as to coincide with each other. When the constant torque control mode is selected, the I control 662 is replaced with the incoming TR current set value I _ETRset from the incoming tension current converter 15. When the constant torque control mode is not selected (constant speed control), the P control 661 and the I control 662 are changed according to the incoming TR speed deviation.

When the constant torque control mode is selected in this state, the current correction 664 corrects the _input TR current command I _ETRref so that it does not change discontinuously. By adopting such a configuration, even during rolling operation, the control mode of the entry side TR control device can be freely switched from constant torque control to constant speed control and constant speed control to constant torque control. A), control method B) and control method C) can be freely switched.

  By using the control configuration as described above, the control method A), the control method B), and the control method C) are switched according to the rolling state, and the optimum control for the outlet side plate thickness control and the inlet side plate thickness control. Since the configuration can be selected, it is possible to greatly improve the outlet side plate thickness accuracy and the operation efficiency. Further, when the control methods B) and C) are switched during acceleration / deceleration of the rolling speed, a certain tension deviation is allowed to give priority to the stability of the outlet side plate thickness. Therefore, it becomes possible to switch between the control methods B) and C) without damaging the delivery side thickness system at the acceleration / deceleration of the rolling speed, and it becomes possible to improve the operation efficiency.

  In the above embodiment, the input side tension deviation is corrected with a dead band, and the input side tension deviation correction value is created. However, the input side tension control operation such as changing the tension control gain according to the tension deviation is performed. Any method may be used as long as the tension control is performed when the control method is switched and the tension deviation is large. When changing the tension control gain, the gain of the gain controllers 74 and 76 described with reference to FIG.

  Moreover, in the said embodiment, the case where the entrance side tension meter 8 was provided for tension control was demonstrated as an example. Not limited to this, it is also possible to estimate the tension based on the difference between the actual value of the output current from the incoming TR controller 66 and the current command value output from the incoming tension current converter 15. For example, when the actual value is higher than the command value, the entry side TR control device 66 is in a state of trying to lower the tension of the material to be rolled, and the tension at that time is set by the entry side tension setting device 11. It can be estimated that the tension is higher than the tension.

  Moreover, in the said embodiment, as demonstrated in FIG. 4, FIG. 5, although the control method A), the control method B), and the control method C) were switched according to the rolling performance, machine specifications and a to-be-rolled material It is also possible to select one of the control methods in advance according to the product specifications and continuously use it. In such a case, the database described in FIG. 6 can be used.

  In the above embodiment, the control method for the ingress TR2 is described. However, the same configuration can be applied to the control method for the egress TR3. Depending on the type of the rolling mill and the material to be rolled, it may be more efficient to operate the delivery side TR when the delivery side tension has a great influence on the plate thickness.

  Further, in the above embodiment, an example assuming a single stand rolling mill has been described, but the rolling mill is not limited to a single stand rolling mill, and in a multi-stand tandem rolling mill, on the entry side or the exit side. Applicable when tension reel is installed. In other words, the entire multi-stand tandem rolling mill is regarded as a rolling mill. As an object, the same control as described above can be performed.

  Moreover, the rolling control apparatus centering on the control method selection apparatus 70 demonstrated in FIG. 1 is implement | achieved by the combination of software and hardware. Here, hardware for realizing each function of the rolling control device according to the present embodiment will be described with reference to FIG. FIG. 23 is a block diagram showing a hardware configuration of an information processing apparatus constituting the rolling control apparatus according to the present embodiment. As shown in FIG. 23, the rolling control apparatus according to the present embodiment has the same configuration as an information processing terminal such as a general server or a PC (Personal Computer).

  That is, the rolling control apparatus according to the present embodiment includes a CPU (Central Processing Unit) 201, a RAM (Random Access Memory) 202, a ROM (Read Only Memory) 203, an HDD (Hard Disk Drive) 204, and an I / F 205. Connected through. Further, an LCD (Liquid Crystal Display) 206 and an operation unit 207 are connected to the I / F 205.

  The CPU 201 is a calculation means and controls the operation of the entire rolling control apparatus. The RAM 202 is a volatile storage medium capable of reading and writing information at high speed, and is used as a work area when the CPU 201 processes information. The ROM 203 is a read-only nonvolatile storage medium and stores a program such as firmware.

  The HDD 204 is a nonvolatile storage medium that can read and write information, and stores an OS (Operating System), various control programs, application programs, and the like. The I / F 205 connects and controls the bus 208 and various hardware and networks. The I / F 205 is also used as an interface for each device to exchange information or input information to the rolling mill.

  The LCD 206 is a visual user interface for the operator to check the state of the rolling control device. The operation unit 207 is a user interface such as a keyboard and a mouse for an operator to input information to the rolling control device. In such a hardware configuration, a program stored in a recording medium such as the ROM 203, the HDD 204, or an optical disk (not shown) is read to the RAM 202, and the CPU 201 performs an operation according to the program, thereby configuring a software control unit. . The function of the rolling control apparatus according to the present embodiment is realized by a combination of the software control unit configured as described above and hardware.

  In the above embodiment, the case where all the functions are included in the rolling control device has been described as an example. In this way, all functions may be realized in one information processing apparatus, or each function may be distributed and realized in more information processing apparatuses.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, it is possible to replace a part of the configuration of a certain embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of a certain embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

1 Rolling machine 2 Incoming TR
3 Outgoing TR
4 Mill speed control device 6 Delivery side TR control device 7 Roll gap control device 8 Entrance side tension meter 9 Exit side tension meter 10 Rolling speed setting device 11 Entrance side tension meter 12 Exit side tension meter 13 Entrance side tension control 14 Exit side tension Control 15 Incoming tension current converter 16 Outlet tension current converter 17 Outlet thickness gauge 18 Outlet thickness controller 19 Standard speed setting device 61 Reduction plate thickness control 62 Speed plate thickness control 63 Speed tension control 64 Reduction tension control 65 Incoming TR speed command device 66 Incoming TR control device 70 Control method selecting device 71 Optimal control method determining device 72 Control output selecting devices 73, 74, 75, 76 Gain controllers 77, 78 Integration processing unit 91 Incoming tension deviation correcting device 92 Upper limit allowable value setting device 93 Lower limit allowable value setting device 94 Deviation correction unit 201 CPU
202 ROM
203 RAM
204 HDD
205 I / F
206 LCD
207 Operation unit

Claims (10)

A roll gap control unit for controlling a distance between rolls of the roll pair in a rolling mill that rolls the material to be rolled with the roll pair;
A speed control unit for controlling a conveyance speed of the material to be rolled inserted into the rolling mill;
A first control method for controlling a conveying speed of the material to be rolled based on the tension of the material to be rolled and controlling the roll gap based on a plate thickness of the material to be rolled; and the material to be rolled Control method switching for switching between the second control method for controlling the roll gap of the material to be rolled based on the tension of the material and controlling the conveyance speed of the material to be rolled based on the thickness of the rolled material to be rolled And
A tension control suppression unit that suppresses the control value of the control based on the fluctuation of the tension of the material to be rolled when switching between the first control method and the second control method; Rolling control device.   The tension control suppression unit suppresses the control value of the control based on the fluctuation of the tension of the material to be rolled down by correcting the deviation of the actually measured value with respect to the target value of the tension of the material to be rolled. The rolling control apparatus according to claim 1, wherein   The rolling according to claim 2, wherein the tension control suppressing unit outputs the deviation as zero when the deviation of the measured value with respect to the target value of the tension of the material to be rolled is within a predetermined range. Control device.   The said tension control suppression part outputs the value which deducted the predetermined value from the said deviation, when the deviation of the measured value with respect to the target value of the tension | tensile_strength of the said rolling material exceeds a predetermined range, It is characterized by the above-mentioned. The rolling control apparatus described in 1.   The rolling control device according to claim 3, further comprising a tension control suppression setting unit that specifies the predetermined range.   The tension control suppression setting unit, when switching between the first control method and the second control method, the predetermined control based on whether the conveyance speed of the material to be rolled is accelerating or decelerating. The rolling control device according to claim 5, wherein a range is designated.   5. The tension control suppressing unit according to claim 3, wherein the tension control suppressing unit narrows the predetermined range in accordance with a lapse of time after switching between the first control method and the second control method. 6. Rolling control device.   The tension control suppression unit suppresses the control value of the control based on the fluctuation of the tension of the material to be rolled to be small by adjusting the gain with respect to the deviation of the actually measured value with respect to the target value of the tension of the material to be rolled. The rolling control apparatus according to claim 1. In the rolling mill that rolls the material to be rolled with a roll pair, the interval between the rolls of the roll pair is controlled,
Control the conveying speed of the material to be rolled inserted into the rolling mill,
A first control method for controlling a conveying speed of the material to be rolled based on the tension of the material to be rolled and controlling the roll gap based on a plate thickness of the material to be rolled; and the material to be rolled The second control method for controlling the roll gap of the material to be rolled based on the tension of the material and controlling the conveyance speed of the material to be rolled based on the thickness of the rolled material to be rolled is switched.
A rolling control method characterized in that, when switching between the first control method and the second control method, a control value of control based on fluctuations in tension of the material to be rolled is suppressed to be small. Controlling the distance between the rolls of the roll pair in a rolling mill that rolls the material to be rolled with the roll pairs;
Controlling the conveying speed of the material to be rolled inserted into the rolling mill;
A first control method for controlling a conveying speed of the material to be rolled based on the tension of the material to be rolled and controlling the roll gap based on a plate thickness of the material to be rolled; and the material to be rolled A step of switching between a second control method of controlling a roll gap of the material to be rolled based on the tension of the material and controlling a conveyance speed of the material to be rolled based on a thickness of the rolled material to be rolled,
When switching between the first control method and the second control method, causing the information processing apparatus to execute a step of suppressing the control value of the control based on the fluctuation of the tension of the material to be rolled to be small. A rolling control program characterized.