JP2005238271A - Controller for continuous steel sheet rolling mill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a continuous steel sheet rolling mill by which the quality of a product in the nose and rear end of the product is improved by performing set changing while continuing an AGC (automatic gage control) control without performing an FGC (flying gage change) control at a setting changing point between approximate schedules. <P>SOLUTION: It is judged to use either of the FGC control or the AGC control by comparing a rolling schedule at a setting changing point which is calculated by a rolling model mechanism 5 by an FGC judging mechanism 8. In the case of using the FGC control, it is judged that an FGC suppressing mechanism 85 is the FGC control between the approximate schedules and whether it is processable by only the AGC control or not and, in the case of YES, the rolling schedule is adjusted within an allowable range of the AGC control by an FGC adjusting mechanism 10A. In the case it is not processable by only the AGC control, a rolling schedule is adjusted by an FGC adjusting mechanism 10B so that the FGC control is preferentially used at stands in the early stage of a plurality of stands which comprise the continuous rolling mill and the rolling schedule is adjusted as so to use the AGC control at the stands in the post-stage. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a control device for a steel plate continuous rolling mill, and more particularly, to a control device for a steel plate continuous cold rolling mill having a rolling model mechanism for calculating a rolling schedule.

  Conventionally, a control device for a steel sheet steel rolling mill has a rolling model mechanism, and the rolling model mechanism calculates the rolling schedule of the steel sheet from the base material dimensions of the given steel sheet, the target dimensions, and the specifications of the rolling mill to be controlled. . In steel plate rolling, there are many disturbances such as a precision error of a rolling model mechanism, a steel plate rolling instruction information error, and a sensor error, and a learning model process for calculating a learning coefficient for correcting these errors is required. The rolling model mechanism keeps the steel sheet rolling optimal by using this learning coefficient. For example, the rolling model mechanism calculates the rolling schedule (for example, rolling dimensions) of two welded preceding and succeeding steel plates, and the FGC (Flying Gage Change) changes at the setting change point based on the difference between the rolling schedules. ) Control or AGC control (Automatic Gage Control) is determined. If the FGC control is determined as a result, the AGC control is stopped and the FGC control is performed.

  As this type of prior art, for example, there is one described in JP-A-9-295020.

Japanese Patent Laid-Open No. 9-295020

  However, the above prior art has the following problems.

  In a control apparatus using a conventional rolling model mechanism, it is determined whether to perform FGC control or AGC control at a setting change point based on a difference between rolling schedules of two welded preceding steel plates and subsequent steel plates. In this case, since the rolling model mechanism uses a learning coefficient, FGC control may be determined even for rolling between steel sheets of approximate specifications (approximate schedule). If the FGC control is determined, the AGC control is stopped and the FGC control is performed. Therefore, the disturbance of the base metal at the leading end of the steel plate cannot be absorbed, and the yield deteriorates due to the quality deterioration of the front and rear end of the steel plate during the FGC control. It was connected to. Thus, if FGC control is performed between steel plates of approximate specifications that are continuous, the thickness accuracy near the joint between the two steel plates will deteriorate, so it is not desirable to frequently perform FGC control.

  However, without using the learning coefficient described above, continuing rolling in a state that includes disturbances such as accuracy errors of the rolling model mechanism, steel sheet rolling instruction information errors, and sensor errors, it is necessary to use a plurality of stands that constitute the rolling mill to be controlled. The load distribution between the stations is disturbed and the setting accuracy of each stand is reduced, which causes a reduction in production efficiency and product quality.

  A first object of the present invention is a steel plate continuous rolling mill that improves the product quality at the rear end of the product by changing the setting while continuing the AGC control without performing the FGC control at the setting change point between the approximate schedules. It is to provide a control device.

  Further, the second object of the present invention is to use the FGC control only in the front stage stand even in the case of performing the FGC control at the setting change point between the approximate schedules, and use the AGC control in the rear stage stand so that the product at the rear end of the product It is providing the control apparatus of the steel plate continuous rolling mill which improves quality.

  In order to achieve the above first object, the present invention uses FGC control or AGC control for a setting change point in a control apparatus for a steel plate continuous rolling mill having a rolling model mechanism for calculating a rolling schedule. A first FGC determination unit that determines whether to use, and a second FGC determination that further determines whether or not the FGC control is FGC control between approximate schedules when it is determined by the first determination unit that FGC control is to be used. And FGC adjustment means for adjusting the rolling schedule so that the setting change amount falls within the AGC control allowable range when the second FGC determination means determines that the FGC control is between the approximate schedules. To do.

  The rolling schedules of the two welded preceding and succeeding steel plates calculated by the rolling model mechanism are compared by the first FGC determination means to determine whether to use FGC control or AGC control. When it is determined that the FGC control is used, the second FGC determination unit further determines whether or not the FGC control is an FGC control between approximate schedules. When it is determined that the FGC control is between the approximate schedules, the FGC adjustment unit adjusts the rolling schedule so that the schedule fluctuation amount falls within an allowable range in which AGC control can be used. As a result, the base material disturbance can be absorbed, and the product quality at the rear end of the product can be improved.

  (2) In the above (1), preferably, when the second FGC determination unit determines that the FGC control is between the approximate schedules, the FGC adjustment unit obtains an AGC control allowable maximum plate thickness difference, A value obtained by adding the AGC control allowable maximum plate thickness difference to the plate thickness before the setting change point is set as a target plate thickness after the setting change point, and AGC control is performed based on the target plate thickness.

  (3) Moreover, in order to achieve the said 2nd objective, this invention performs FGC control with respect to a setting change point in the control apparatus of the steel plate continuous rolling mill provided with the rolling model mechanism which calculates a rolling schedule. First FGC determination means for determining whether to use or AGC control, and whether or not the FGC control is FGC control between approximate schedules when the first determination means determines that FGC control is to be used. When it is determined by the second FGC determination means to determine and the FGC control between the approximate schedules by the second FGC determination means, the priority is high according to the priority order determined for each of a plurality of stands constituting the steel continuous rolling mill. FGC adjustment means for adjusting the rolling schedule so that the AGC control is preferentially used in the stand and the FGC control is used in the other stand. To.

  The rolling schedules of the two welded preceding and succeeding steel plates calculated by the rolling model mechanism are compared by the first FGC determination means to determine whether to use FGC control or AGC control. When it is determined that the FGC control is used, the second FGC determination unit further determines whether or not the FGC control is an FGC control between approximate schedules. When it is determined that the FGC control is between the approximate schedules, the FGC adjustment means uses AGC control preferentially at the higher priority stand according to the priority order determined for each of the plurality of stands constituting the steel continuous rolling mill, and the like. Adjust the rolling schedule to use FGC control at the stand. As a result, the rolling mills subject to FGC control are limited to the low priority stands, and AGC control is partially continued on the high priority stands, so the disturbance of the base material is absorbed and the product quality at the front and rear ends of the product is improved. It becomes possible to do.

  (4) Furthermore, in order to achieve the above first and second objects, the present invention provides a control device for a steel sheet steel continuous rolling mill having a rolling model mechanism for calculating a rolling schedule. First FGC determination means for determining whether to use FGC control or AGC control, and when it is determined by the first determination means to use FGC control, the FGC control is FGC control between approximate schedules; A second FGC determination unit that further determines whether or not it can be handled only by AGC control, and a setting change amount when it is determined by the second FGC determination unit that FGC control is performed between approximate schedules and that only AGC control is available. Is approximated by the first FGC adjusting means for adjusting the rolling schedule so as to be within the AGC control allowable range and the second FGC determining means. When it is determined that the AGC control cannot be handled only by the AGC control, the AGC control is preferentially used in the high priority stand according to the priority order determined for each of the plurality of stands constituting the steel continuous rolling mill, The second FGC adjusting means for adjusting the rolling schedule so as to use the FGC control in another stand is provided.

  The rolling schedules of the two welded preceding and succeeding steel plates calculated by the rolling model mechanism are compared by the first FGC determination means to determine whether to use FGC control or AGC control. When it is determined that the FGC control is used, the second FGC determination means determines whether the FGC control is FGC control between the approximate schedules and can be handled only by the AGC control, and the FGC control between the approximate schedules is performed. When it is determined that only the AGC control is available, the first FGC adjusting means adjusts the rolling schedule so that the schedule fluctuation amount is within an allowable range in which the AGC control can be used. As a result, the base material disturbance can be absorbed, and the product quality at the rear end of the product can be improved. In addition, when it is determined that the AGC control alone is not able to cope with the approximate schedule, the second FGC adjusting means preferentially performs the AGC on the higher priority stand according to the priority order determined for each of the plurality of stands constituting the steel continuous rolling mill. Use the controls to adjust the rolling schedule to use FGC controls on the other stands. As a result, the rolling mills subject to FGC control are limited to low priority stands and AGC control is partially continued on the high priority stands, so the disturbance of the base material is absorbed and the product quality at the front and rear ends of the product is improved. It becomes possible to do.

  (5) In the above (4), preferably, when the schedule difference at the setting change point is smaller than the first reference value, the second determination means performs FGC control between approximate schedules and only AGC control. If the schedule difference at the setting change point is larger than the first reference value and smaller than the first reference value, it is determined that the FGC control is performed between the approximate schedules but the AGC control alone cannot be used. To do.

  According to the present invention, even in continuous rolling of steel plates of two different base materials and product dimensions, it becomes possible to effectively operate AGC control that absorbs the base material disturbance, and it is possible to improve the quality of the product leading and trailing ends. Become.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a system configuration diagram showing an embodiment of the present invention.

  In FIG. 1, a control device 1 is a computer device that controls a metal steel plate production facility with a continuous rolling mill, for example, a cold continuous rolling mill composed of a plurality of stands, and a DDC 2 receives a control signal output from the control device 1. . The DDC 2 takes in the control state of the control object 4 from the sensor 3 and outputs a control output for performing control in accordance with the output of the control device 1.

  The control device 1 includes a rolling model mechanism 5, a control memory 6, an FGC determination mechanism 8, a DDC output processing mechanism 9, and an FGC adjustment mechanism 10.

  The rolling model mechanism 5 includes a learning model, takes in the rolling instruction information of the metal steel plate from the control memory 6, and outputs a rolling schedule 7.

  The FGC determination mechanism 8 determines whether FGC control is appropriate or AGC control is appropriate at the welding point of the steel sheet, which is the next setting change point, from two successive rolling schedules. When it is determined that the AGC control is appropriate for the setting change point, the FGC determination mechanism 8 sets the rolling schedule 7 to the DDC 2 via the DDC output process 9. Further, even when the FGC control is appropriate and the FGC control is determined when the determination result of the FGC determination mechanism 8 is appropriate, the rolling schedule 7 is set to the DDC 2 via the DDC output processing 9. When the determination result of the FGC determination mechanism 8 is that the FGC control is appropriate and the FGC control is not fixed, the rolling schedule 7 is output to the FGC adjustment mechanism 10.

  The FGC adjusting mechanism 10 adjusts the load distribution between the stands so that the rolling schedule 7 falls within the AGC allowable range, and outputs a load distribution correction 11A to the rolling model mechanism 3. Further, when the FGC adjustment process 10 determines that the adjustment to the AGC control allowable range is impossible by the FGC determination mechanism 8, the FGC adjustment process 10 determines the stand using the FGC control and the stand using the AGC control according to the priority order between the respective stands. The load distribution correction 11B is output to the rolling model mechanism 3 so as to avoid the FGC control for all the stands.

  Next, the rolling model mechanism 5 will be described with reference to FIG.

  FIG. 2 is a flowchart showing the rolling model mechanism 5 of the present invention. The initial reduction ratio is determined from conditions such as the base material dimensions and product dimensions given in advance in the initial reduction ratio determination processing 51. The tension calculation process 52 refers to the rolling schedule determined in the initial rolling reduction determination process 51 and determines the tension before and after each stand. In the rolling speed determination processing 53, the maximum rolling speed is calculated from the conditions of the motor rotation speed and rolling speed of each stand with reference to the specifications of the rolling mill that is the control object 4. In the rolling load and roll flatness calculation processing 54, conditions such as the rolling speed determined in the rolling speed calculation processing 53 are input, and the rolling load and roll flatness of each stand are determined. Torque calculation processing 55 calculates torque and horsepower. The rolling load and roll flatness calculation process 54 and the torque calculation process 55 are repeated for all the stands. These processes include calculations using learning coefficients.

  The load distribution determination mechanism 56 determines whether the load of all the stands is within the motor allowable range and whether the load distribution of all the stands is within the motor allowable range. Details thereof will be described later.

  The rolling reduction distribution correction processing 57 adjusts the rolling reduction ratio of each stand in a direction that falls within the allowable range when the load distribution determination mechanism 56 does not fall within the allowable range. The FGC stand limitation processing 58 is performed when the FGC stand limitation mode is selected (see processing 856 in FIG. 5 described later), and when the load distribution determination mechanism 56 determines that the load distribution of the target stand is appropriate. Further restrict the target stands. The reduction position calculation process 59 calculates the reduction position of each stand from the rolling load and the rolling load calculated in the roll flatness calculation process 54.

  The FGC determination mechanism 8 determines whether the FGC control is appropriate or the AGC control is appropriate at the next setting change point from the reduction position calculated in the reduction position calculation processing 59. The DDC output process 9 is performed when it is determined that the AGC control is appropriate based on the determination result of the FGC determination mechanism 8 and when the FGC control is determined.

  The DDC output process 9 edits items necessary for the DCC 2 to control the control target 4 and outputs the edited items to the DDC 2.

  The FGC adjustment processing 10 performs FGC adjustment when the determination result of the FGC determination mechanism 8 is FGC control but it is determined that adjustment is possible so that AGC control can be applied. At this time, when it is determined that the FGC control is appropriate based on the determination result of the FGC determination mechanism 8 and the rolling schedule fluctuation amount is not large and can be within the AGC control allowable range, each stand reduction rate is adjusted. Thus, the rolling schedule is adjusted, and recalculation is performed from the tension calculation processing 52. This flow is the load distribution correction 11A. On the other hand, if it is determined that the FGC control is appropriate based on the determination result of the FGC determination mechanism 8 and the FGC stand limitation mode is selected, the limitation processing of the FGC control target stand is performed. This flow is the load distribution correction 11B.

  Next, the details of the load distribution determination mechanism 56 will be described with reference to FIG.

  FIG. 3 is a flowchart showing details of the load distribution adjusting mechanism 56 of the present invention. The load distribution adjustment mechanism 56 determines whether or not load distribution determination is necessary, and if so, whether or not the loads of all the stands are within the motor allowable range, and whether the load distribution of all the stands is within the motor allowable range. This determination is performed. The FGC adjustment mode determination processing 561 proceeds to processing 564 when the FGC determination mechanism 8 determines that the FGC control is appropriate, and when it is determined that the rolling schedule fluctuation amount is not large and can be within the AGC control allowable range, the processing proceeds to step 564. It is determined that the distribution determination is unnecessary. The load distribution determination process 562 repeatedly determines whether or not the load distribution is appropriate for the necessary number of stands. If the determination result is NG, the process proceeds to the FGC stand limited mode determination process 563, and the FGC determination mechanism 8 performs the limit process of the FGC control target stand. Is determined to be necessary, the load distribution determination is determined to be NG1, and if it is not determined to be required, the process proceeds to step 566 to determine NG2.

  If it is determined that the load distribution determination is unnecessary in the FGC adjustment mode determination processing 561, the process proceeds to the reduction position calculation processing 59 in FIG. 2, and if it is determined as NG1 in the FGC stand limited mode determination processing 563 (in the FGC determination mechanism 8) If it is determined that the limitation process of the FGC control target stand is necessary) or the load distribution determination 562 determines that the load distribution of all the stands is appropriate (OK), the process proceeds to the FGC stand limitation process 58 of FIG. When it is determined as NG2 in the FGC stand limited mode determination process 563 (when it is not determined that the FGC determination mechanism 8 needs to limit the FGC control target stand), the rolling reduction distribution correction process 57 in FIG. Proceed to

  Next, the details of the FGC determination mechanism 8 will be described with reference to FIG.

FIG. 4 is a flowchart showing details of the FGC determination mechanism 8 of the present invention. The FGC determination mechanism 8 calculates the setting change amount of each stand for the next setting change point, and determines whether the FGC control is appropriate. The reduction position difference determination processing 81 determines whether or not the reduction position difference of each stand is larger than the AGC control maximum reduction position difference. If it is larger, it is determined that the FGC control is appropriate. The formula for calculating the reduction position is shown in Formula 1.

Rolling position difference = plate thickness 2−plate thickness 1 + {(load 1−load 2) / mil rigidity 2} (Formula 1)

| Driving position difference |> AGC control maximum reduction position difference (Formula 2)

Here, auxiliary numeral 1 indicates the steel sheet before the setting change point, and 2 indicates the steel sheet after the setting change point. Next, in the plate thickness variation determination process 82, is the plate thickness difference on the stand exit side larger than the AGC control maximum plate thickness difference? If it is larger, it is determined that the FGC control is appropriate. The plate thickness calculation formula is shown in Formula 3.

Thickness difference = Thickness 2-Thickness 1 (Formula 3)

| Thickness difference |> AGC control maximum thickness difference (Formula 4)

Next, in a plate thickness variation rate determination process 83, it is determined whether or not the plate thickness variation rate on the outlet side of each stand is larger than the AGC control maximum plate thickness variation rate. If it is large, it is determined that the FGC control is appropriate. . The plate thickness calculation formula is shown in Formula 5.

Plate thickness fluctuation rate = (plate thickness 2−plate thickness 1) / plate thickness 2 (Formula 5)

| Thickness variation rate |> AGC control maximum thickness variation rate (Formula 6)

If all the determination results of the rolling position difference determination processing 81, the plate thickness variation determination processing 82, and the plate thickness variation rate determination processing 83 are equal to or less than the reference value, it is determined that the AGC control is appropriate in the AGC determination determination processing 84. If any one of them is larger than the reference value, the FGC suppression mechanism 85 adjusts and determines the FGC type.

  Next, the details of the FGC suppressing mechanism 85 will be described with reference to FIG.

  FIG. 5 shows details of the FGC suppressing mechanism 85 of the present invention. The FGC suppression type determination process 851 determines whether the FGC suppression type has already been determined. If the FGC suppression type determination process 851 has already been determined, the process proceeds to the previous determination type selection process 855, ends the process with the mode determined last time being determined, and has not been processed. In the case of determination, FGC adjustment determination processing 852 is executed. The FGC adjustment determination process 852 compares the rolling schedules before and after the setting change point, and if the difference is within the reference value 1, the process proceeds to the AGC selection process 854 to select AGC control. The FGC adjusting mechanism 10 receives the result, corrects the rolling reduction of each stand as will be described later, and adjusts the rolling schedule so that AGC control can be used.

  If the difference in the rolling schedule is larger than the reference value 1 in the FGC adjustment determination process 852, it is determined that the FGC adjustment within the AGC allowable range is impossible, and the FGC limitation determination process 853 performs the limitation process for the FGC control target stand. If the rolling schedule difference before and after the design change point is equal to or less than the reference value 2, the FGC limitation determination processing 853 proceeds to the FGC stand limitation mode selection processing 856 and selects the FGC stand limitation mode. The FGC adjusting mechanism 10 receives the result, adjusts the rolling schedule within a range where AGC control can be applied from the rear stage stand, as will be described later, and allows the difference in the rolling schedule to be absorbed only by the front stage stand. When the rolling schedule difference before and after the design change point is larger than the reference value 2, the process proceeds to the normal FGC selection process 857, and the normal FGC is applied.

  The reference value 1 and the reference value 2 are for determining a difference in rolling schedules before and after the setting change point calculated from the base material dimensional difference, the target dimensional difference, and the steel type difference. For the reference value 1, a value smaller than the reference value 2 is applied to make the determination condition stricter.

An example of the reference values 1 and 2 is shown below.
<Reference value 1>
・ Target plate pressure difference The following values are calculated for 5 stand exit side plate pressure difference from 1 stand exit side.

0.060mm, 0.050mm, 0.040mm, 0.030mm, 0.020mm
・ Entry side pressure difference
0.100mm
・ Plate width
50mm
・ Stand pressure reduction difference (calculated by process 59 in FIG. 2)
The following values for 1 stand and 5 stands respectively.

0.080mm, 0.070mm, 0.060mm, 0.050mm, 0.040mm
・ Hardness class difference 1 (equivalent to 3.0 kg / mm ^{2 in} terms of yield point)
<Reference value 2>
・ Target plate pressure difference The following values are calculated for 5 stand exit side plate pressure difference from 1 stand exit side.

0.080mm, 0.070mm, 0.060mm, 0.050mm, 0.040mm
・ Entry side pressure difference
0.100mm
・ Plate width
50mm
・ Stand pressure reduction difference (calculated by process 59 in FIG. 2)
The following values for 1 stand and 5 stands respectively.

0.100mm, 0.090mm, 0.080mm, 0.070mm, 0.060mm
・ Hardness class difference 1 (equivalent to 3.0 kg / mm ^{2 in} terms of yield point)
Next, the details of the FGC adjustment mechanism 10 will be described with reference to FIGS. 6 and 7.

  The FGC adjustment mechanism 10 includes an FGC adjustment mechanism 10A when AGC control is selected in the AGC selection process 854 of FIG. 5 and an FGC adjustment mechanism when the FGC stand limited mode selection process 856 of FIG. 5 is selected. FIG. 6 shows details of the FGC adjustment mechanism 10A, and FIG. 7 is a flowchart showing details of the FGC adjustment mechanism 10B.

  In FIG. 6, the FGC adjusting mechanism 10A performs an AGC control allowable maximum plate thickness difference calculation process 111 and a plate thickness calculation process 112 after the setting change point.

Formula 7 shows the calculation formula of the AGC control allowable maximum plate thickness difference calculation processing 111.

AGC control maximum allowable plate thickness difference = Min (plate thickness difference 1, plate thickness difference 2) (Formula 7)

The plate thickness difference 1 is the AGC controlled maximum plate thickness difference in the above (Formula 4), and the plate thickness difference 2 is the plate obtained from the AGC controlled maximum plate thickness variation rate in the above (Formula 6) and the steel plate thickness before the next setting change point. It is a thickness difference.

Formula 8 shows the calculation formula of the plate thickness calculation process 112 after the setting change point.

Thickness 2 = Thickness 1 ± AGC control allowable maximum thickness difference (Formula 8)

As a result, the difference between the plate thickness 2 and the plate thickness 1 falls within the AGC control allowable maximum value, and the next setting change point can be processed by the AGC control.

  In FIG. 7, the FGC adjustment mechanism 10B performs AGC control according to the priority order determined for each stand when the determination result of the FGC determination processing 8 is not AGC control and the product plate thickness is approximate. . First, the rolling model mechanism input process 121 fixes the setting of the priority stand N machine within the AGC control application range based on the steel plate before the next setting change point, and inputs it to the rolling model mechanism 5. The load distribution determination process 122 determines whether or not the load distribution of the rolling schedule obtained as a result is within the allowable range, and if it is within the allowable range, the rolling schedule is adopted as effective. This process starts from the highest priority stand and repeats until the second highest priority stand. As a result, it is possible to obtain a schedule that is closest to the steel plate before the next setting change point within a proper range of load distribution. The load distribution determination process 122 and the rolling schedule update process 123 use the functions of the load distribution determination mechanism 56 and the FGC stand limitation process 58 of the rolling model mechanism.

  The above is AGC control according to the priority order determined for each stand. However, the front stand may be preferentially FGC controlled and the rear stand may be AGC controlled. In this case, first, the rolling model mechanism input process 121 fixes the setting of the rear stage N machine to a range where AGC control can be applied based on the steel plate before the next setting change point, and inputs it to the rolling model mechanism 5. The load distribution determination process 122 determines whether the load distribution of the rolling schedule obtained as a result is within the allowable range. If the load distribution is within the allowable range, the rolling schedule update process 123 sets the setting of the rear stage N machine. A fixed rolling schedule is adopted as effective. This process starts from the last fixed stand number only, and repeats until the second stand is fixed. As a result, it is possible to obtain a schedule that is closest to the steel plate before the next setting change point within a proper range of load distribution.

  In the present embodiment configured as described above, the FGC determination mechanism 8 compares the rolling schedules of the two welded preceding and subsequent steel plates calculated by the rolling model mechanism 5 and uses the FGC control or the AGC control. Determine whether to use. If the FGC determination mechanism 8 determines that the FGC control is to be used, the FGC determination mechanism 8 further uses the FCG suppression determination mechanism 85 to determine whether the FGC control is FGC control between approximate schedules and only AGC control is possible. If it is determined that the FGC control is performed between the approximate schedules and it is determined that only the AGC control is available, the FGC adjustment mechanism 10A has a schedule fluctuation amount that falls within an allowable range in which the AGC control can be used. Adjust the rolling schedule. As a result, the base material disturbance can be absorbed, and the product quality at the rear end of the product can be improved. In addition, when it is determined that the AGC control is not possible only with the approximate schedule, the FGC adjustment mechanism 10B preferentially performs the AGC on the higher priority stand according to the priority order determined for each of the plurality of stands constituting the steel continuous rolling mill. Use the controls to adjust the rolling schedule to use FGC controls on the other stands. As a result, the FGC controlled rolling mill is limited to a high-priority stand (for example, a front-stage stand) and AGC control is partially continued at a low-priority stand (for example, a rear-stage stand). It becomes possible to improve the product quality at the rear end of the product.

  Therefore, according to the present embodiment, AGC control that absorbs the disturbance of the base material can be effectively performed even in continuous rolling of steel plates having two different base materials and product dimensions, and the quality of the front and rear ends of the product can be improved. Improvement is possible.

  In the above-described embodiment, two FGC adjustment mechanisms, that is, the FGC adjustment mechanism 10A when performing AGC control and the FGC adjustment mechanism 10B when performing FGC stand-limited processing are used as the FGC adjustment mechanism. Even in this case, the base material disturbance can be absorbed and the product quality at the rear end of the product can be improved as compared with the case where no FGC adjustment mechanism is used.

It is a system block diagram of the control apparatus of the steel plate continuous rolling mill concerning one embodiment of this invention. It is a flowchart which shows the detail of a rolling model mechanism. It is a flowchart which shows the detail of a load distribution determination mechanism. It is a flowchart which shows the detail of a FGC determination mechanism. It is a flowchart which shows the detail of a FGC suppression mechanism. It is a flowchart which shows the detail of the FGC adjustment mechanism in the case of selecting AGC control. It is a flowchart which shows the detail of the FGC adjustment mechanism in the case of selecting FGC stand only mode.

Explanation of symbols

1 Controller 2 DDC
3 Sensor 4 Control object 5 Rolling model mechanism 6 Control memory 7 Rolling schedule 8 FGC determination mechanism 9 DDC output processing mechanism 10 (10A, 10B) FGC adjustment mechanism 111 AGC control allowable maximum plate thickness difference calculation process 112 After setting change point Sheet thickness calculation process 112
121 Rolling model mechanism input processing 122 Load distribution determination processing 123 Rolling schedule update processing

Claims (5)

In the control device of a steel plate continuous rolling mill equipped with a rolling model mechanism for calculating the rolling schedule,
First FGC determination means for determining whether to use FGC control or AGC control for the setting change point;
Second FGC determination means for further determining whether or not the FGC control is FGC control between approximate schedules when it is determined by the first determination means to use FGC control;
FGC adjustment means for adjusting the rolling schedule so that the set change amount falls within the AGC control allowable range when the second FGC determination means determines that the FGC control is between the approximate schedules. Control device for continuous rolling mill for steel and steel plate.   2. The control apparatus for a steel sheet continuous rolling mill according to claim 1, wherein the FGC adjustment means determines that the AGC control allowable maximum plate thickness difference is determined by the second FGC determination means to be FGC control between approximate schedules. The value obtained by adding the AGC control allowable maximum plate thickness difference to the plate thickness before the setting change point is used as the target plate thickness after the setting change point, and AGC control is performed by this target plate thickness. Control device for continuous rolling mills. In the control device of a steel plate continuous rolling mill equipped with a rolling model mechanism for calculating the rolling schedule,
First FGC determination means for determining whether to use FGC control or AGC control for the setting change point;
Second FGC determination means for further determining whether or not the FGC control is FGC control between approximate schedules when it is determined by the first determination means to use FGC control;
When it is determined by the second FGC determination means that the FGC control is between approximate schedules, the AGC control is preferentially performed at a higher priority stand according to the priority order determined for each of the plurality of stands constituting the steel continuous rolling mill. A control apparatus for a steel and steel sheet continuous rolling mill, comprising: an FGC adjusting means that adjusts a rolling schedule so as to use FGC control in another stand. In the control device of a steel plate continuous rolling mill equipped with a rolling model mechanism for calculating the rolling schedule,
First FGC determination means for determining whether to use FGC control or AGC control for the setting change point;
Second FGC determination means for further determining whether or not the FGC control is FGC control between approximate schedules and can be handled only by AGC control when the first determination means determines that FGC control is used;
The first FGC adjusting means for adjusting the rolling schedule so that the setting change amount falls within the AGC control allowable range when it is determined by the second FGC determining means that the FGC control is performed between the approximate schedules and only the AGC control is available. When,
When the second FGC determination means determines that FGC control between approximate schedules is not possible only by AGC control, a stand having a high priority according to a priority determined for each of a plurality of stands constituting the steel continuous rolling mill. And a second FGC adjusting means for adjusting the rolling schedule so that the AGC control is preferentially used and the FGC control is used in another stand. 5. The control apparatus for a steel sheet continuous rolling mill according to claim 4, wherein when the schedule difference at the setting change point is smaller than the first reference value, the second determination means is FGC control between approximate schedules and AGC. When it is determined that only the control can cope, and the schedule difference at the setting change point is larger than the first reference value and smaller than the first reference value, the FGC control is performed between the approximate schedules, but the AGC control alone is available. A control device for a steel plate continuous rolling mill characterized in that it is determined that it cannot be performed.

Images