Processing device, processing method, and program

Abstract

To achieve both suppression in shape deterioration of a rolled material and high response of temperature control when a temperature of the rolled material is controlled on the outlet side of a finishing rolling machine.SOLUTION: A processor 80 calculates a correction amount δ(n) of a finishing rolling machine outlet side temperature on the basis of a measured value θF,n of the finishing rolling machine outlet side temperature, and a calculated value Tcal,n of the finishing rolling machine outlet side temperature, and determines an operation amount zk,j of temperature regulators 40 and 51-56 on the basis of the correction amount δ(n) of the finishing rolling machine outlet side temperature.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a processing apparatus, a processing method, and a program.

Background Art

[0002] Hot-rolled thin steel sheets are manufactured through the following steps. First, a slab, which is a rolling material, is heated in a heating furnace. Then, the slab is roughly rolled by a roughing mill to form a rough bar. Subsequently, the rough bar is finish-rolled by a finishing tandem rolling mill equipped with a plurality of rolling stands. In this way, hot-rolled thin steel sheets are manufactured. In finish rolling, in order to ensure the mechanical properties of the rolling material such as strength and ductility, the temperature of the rolling material is controlled at the position on the outlet side of the finishing tandem rolling mill (temperature control position). As a temperature control device for adjusting the temperature of the rolling material, for example, a rough bar heating device for heating the rough bar between the roughing mill and the finishing tandem rolling mill, a rough bar cooling device for cooling the rough bar between the roughing mill and the finishing tandem rolling mill, and a cooling spray device for cooling the rolling material between the rolling stands of the finishing tandem rolling mill are used.

[0003] As a method for controlling the temperature of the rolling material during such finish rolling, there are techniques disclosed in Patent Documents 1 to 3. In the method disclosed in Patent Document 1, a plurality of control points are set over the rolling direction on the rough bar, the temperature of each control point on the outlet side of the roughing mill is measured, and based on the measured temperature, the temperature of each control point on the outlet side of the finishing tandem rolling mill is predicted, and the rough bar heater and the cooling spray device are operated so that the temperature of each control point on the predicted outlet side of the finishing tandem rolling mill becomes the target temperature. However, the control by this method is a feed-forward control of the temperature of the rolling material on the outlet side of the roughing mill. Therefore, if there is an error in the predicted temperature of each control point, the temperature on the outlet side of the finishing tandem rolling mill for each control point does not match the target temperature. Therefore, in the methods disclosed in Patent Documents 2 and 3, the temperature of the rolling material on the outlet side of the finishing tandem rolling mill is controlled by combining the feed-forward control and the feedback control of the temperature of the rolling material on the outlet side of the finishing tandem rolling mill.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the feedback control disclosed in Patent Documents 2 and 3 corrects the operation amount of the temperature control device by performing proportional-integral control on the deviation between the measured value and the target value of the temperature of the rolled material on the outlet side of the finishing tandem rolling mill. When performing feedback control based on the deviation between the measured value and the target value in this way, what becomes important is the dead time from when the operation amount is corrected until the result appears in the measured value. Since the smaller this dead time is, the easier it is to make the control highly responsive, in the feedback control disclosed in Patent Document 2, the operation amount is corrected preferentially from the temperature control device located downstream among the plurality of temperature control devices. However, when a temperature change of the rolled material occurs, the thicker the plate thickness, the less likely a shape change of the rolled material occurs. From such a perspective, it is desirable to preferentially use the temperature control device located upstream, and actually, the feedforward control disclosed in Patent Documents 2 and 3 does so. Therefore, when applying the feedback control disclosed in Patent Document 2, the dead time becomes smaller, but there is a risk that the shape of the rolled material deteriorates.

[0006] Therefore, in the feedback control disclosed in Patent Document 3, the operation amount of the temperature control device located most upstream among the temperature control devices that have not reached the saturation state is corrected. However, in this method, although the shape of the rolled material is less likely to deteriorate compared to the method disclosed in Patent Document 2, the dead time becomes longer, so high-response control is not easy. As described above, in the method of feeding back the deviation between the measured value and the target value of the temperature of the rolled material on the outlet side of the finishing tandem rolling mill to the operation amount of the temperature control device, it is impossible to achieve both suppression of the shape deterioration of the rolled material and high responsiveness of temperature control.

[0007] The present invention has been made in view of such problems, and an object thereof is to achieve both suppression of the shape deterioration of the rolled material and high responsiveness of temperature control when controlling the temperature of the rolled material on the outlet side of the finishing rolling mill.

Means for Solving the Problems

[0008] The processing device of the present invention is a processing device that determines the operation amount of a temperature control device that adjusts the temperature of a rolled material being conveyed between the outlet side of a rough rolling mill and the outlet side of a finishing rolling mill, and includes a finishing rolling mill outlet side temperature acquisition means for acquiring a measured value of the finishing rolling mill outlet side temperature, which is the temperature of the rolled material on the outlet side of the finishing rolling mill, a temperature calculation means for calculating a calculated value of the finishing rolling mill outlet side temperature based on the latest value of the operation amount of the temperature control device, a correction amount calculation means for calculating a correction amount of the finishing rolling mill outlet side temperature based on the measured value of the finishing rolling mill outlet side temperature acquired by the finishing rolling mill outlet side temperature acquisition means and the calculated value of the finishing rolling mill outlet side temperature calculated by the temperature calculation means, and an operation amount determination means for determining the operation amount of the temperature control device with respect to the rolled material for which the measured value of the finishing rolling mill outlet side temperature has been acquired based on the correction amount of the finishing rolling mill outlet side temperature. , a plurality of control points are set for the rolled material at intervals in the conveying direction of the rolled material, and when the temperature calculation means obtains a measured value of the temperature on the outlet side of the finishing rolling mill at one of the control points, the temperature calculation means calculates a calculated value of the temperature on the outlet side of the finishing rolling mill at the control point, and the correction amount calculation means calculates a correction amount of the temperature on the outlet side of the finishing rolling mill at the control point based on the measured value of the temperature on the outlet side of the finishing rolling mill at the control point and the calculated value of the temperature on the outlet side of the finishing rolling mill at the control point, and the operation amount determination means determines the operation amount of the temperature adjustment device for all the control points located on the rear end side of the control point existing at the measurement position of the temperature on the outlet side of the finishing rolling mill based on the correction amount of the temperature on the outlet side of the finishing rolling mill at the control point, and the operation amount determination means identifies a temperature adjustment device located downstream of the position where the control point exists for all the control points located on the rear end side of the control point existing at the measurement position of the temperature on the outlet side of the finishing rolling mill, and only updates the operation amount of the temperature adjustment device located downstream of the position where the control point exists provided.

[0009] The processing method of the present invention is a processing method for determining an operation amount of a temperature adjustment device that adjusts the temperature of a rolled material being conveyed between the outlet side of a rough rolling mill and the outlet side of a finishing rolling mill. The method includes a step of obtaining a measured value of the finishing rolling mill outlet side temperature, which is the temperature of the rolled material at the outlet side of the finishing rolling mill; a temperature calculation step of calculating a calculated value of the finishing rolling mill outlet side temperature based on the latest value of the operation amount of the temperature adjustment device; a correction amount calculation step of calculating a correction amount of the finishing rolling mill outlet side temperature based on the measured value of the finishing rolling mill outlet side temperature obtained in the finishing rolling mill outlet side temperature acquisition step and the calculated value of the finishing rolling mill outlet side temperature calculated in the temperature calculation step; and an operation amount determination step of determining the operation amount of the temperature adjustment device for the rolled material for which the measured value of the finishing rolling mill outlet side temperature is obtained based on the correction amount of the finishing rolling mill outlet side temperature. , a plurality of control points are set for the rolled material at intervals in the conveying direction of the rolled material, and in the temperature calculation step, when a measured value of the temperature on the outlet side of the finishing rolling mill at one of the control points is obtained, the temperature calculation step calculates a calculated value of the temperature on the outlet side of the finishing rolling mill at the control point, and in the correction amount calculation step, a correction amount of the temperature on the outlet side of the finishing rolling mill at the control point is calculated based on the measured value of the temperature on the outlet side of the finishing rolling mill at the control point and the calculated value of the temperature on the outlet side of the finishing rolling mill at the control point, and in the operation amount determination step, the operation amount of the temperature adjustment device for all the control points located on the rear end side of the control point existing at the measurement position of the temperature on the outlet side of the finishing rolling mill is determined based on the correction amount of the temperature on the outlet side of the finishing rolling mill at the control point, and in the operation amount determination step, for all the control points located on the rear end side of the control point existing at the measurement position of the temperature on the outlet side of the finishing rolling mill, a temperature adjustment device located downstream of the position where the control point exists is identified, and only the operation amount of the temperature adjustment device located downstream of the position where the control point exists is updated is provided.

[0010] The program of the present invention is for causing each means to function as the processing device.

Advantages of the Invention

[0011] According to the present invention, a correction amount of the finishing rolling mill outlet side temperature is calculated based on the measured value of the finishing rolling mill outlet side temperature and the calculated value of the finishing rolling mill outlet side temperature, and the operation amount of the temperature adjustment device is determined based on the correction amount of the finishing rolling mill outlet side temperature. Therefore, it is possible to operate from a temperature adjustment device on the upstream side in the same manner as when performing feedforward control. Also, unlike the method of performing feedback control based on the temperature deviation between the measured value and the target value of the finishing rolling mill outlet side temperature, it is possible to perform feedback control without being affected by dead time. Thus, when controlling the temperature of the rolled material at the outlet side of the finishing rolling mill, it is possible to achieve both suppression of deterioration in the shape of the rolled material and high responsiveness of temperature control.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

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Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, when the comparison targets such as length, position, size, interval, etc. are the same, it includes not only the case of being exactly the same but also those that are different within the range not departing from the gist of the invention (for example, those that are different within the tolerance range determined at the time of design). <Rolling Equipment 100> FIG. 1 is a diagram showing an example of the configuration of rolling equipment 100. The rolling equipment 100 rolls the rolled material 1 on a conveyance path R formed in the rolling equipment 100. The conveyance path R is a space formed in the rolling equipment 100 for rolling while conveying the rolled material 1 from the upstream side D1 to the downstream side D2 in the conveyance direction D.

[0014] The rolling equipment 100 includes a rough rolling mill 10, a finishing tandem rolling mill (finishing rolling mill) 20, a tracking device 30, a rough bar cooling device 40, cooling spray devices 51 to 56, a thermometer on the exit side of the rough rolling mill 60, and a thermometer on the exit side of the finishing rolling mill 70. The rough rolling mill 10 and the finishing tandem rolling mill 20 each roll the rolled material 1 on the conveying path R. The rough rolling mill 10 roughly rolls the rolled material 1. The rolled material 1 roughly rolled by the rough rolling mill 10 is also referred to as a rough bar. The finishing tandem rolling mill 20 is installed on the downstream side D2 in the conveying direction D from the rough rolling mill 10. The finishing tandem rolling mill 20 finish-rolls the rolled material 1 roughly rolled by the rough rolling mill 10. The finishing tandem rolling mill 20 includes a plurality of (seven in this embodiment) rolling stands (rolling mills) F1 to F7. The rolling stands F1 to F7 are installed in the order of rolling stand F1, rolling stand F2, ···, rolling stand F7 from the upstream side D1 to the downstream side D2 in the conveying direction D.

[0015] A plurality of control points are set at intervals from each other in the conveying direction D on the rolled material 1. FIG. 2 is a diagram for explaining an example of the control points. In FIG. 2, the position of the tip of the arrow line indicates the control point. The control point indicates the temperature control position (control point) on the rolled material 1 (it is not the case that information indicating the control point is attached to the rolled material 1). Here, among the plurality of control points, the k-th control point from the downstream side D2 to the upstream side D1 in the conveying direction D shall be referred to as the k-th control point. Let the number of the plurality of control points be N. That is, k is an integer of 1 or more and N or less. For example, in FIG. 2, the position of the tip of the arrow line shown below k = 1 indicates the first control point. Similarly, the positions of the tips of the arrow lines shown below k = 2, 3, ··· N - 2, N - 1, N indicate the second control point, the third control point, ···, the (N - 2)-th control point, the (N - 1)-th control point, and the N-th control point, respectively.

[0016] In FIG. 2, a case is illustrated where the first control point is the position of the tip of the rolled material 1 and the N-th control point is the position of the rear end of the rolled material 1. Also, in FIG. 2, a case is illustrated where the intervals between two adjacent control points in the conveying direction D are equal intervals. Thus, it is preferable that the plurality of control points are set at a constant pitch from the tip to the rear end in the conveying direction D of the rolled material 1. However, as long as a plurality of positions on the rolled material 1 in the conveying direction D where temperature control is performed are set as a plurality of control points, the plurality of control points do not necessarily have to be set as shown in FIG. 2.

[0017] The rough rolling mill outlet thermometer 60 is installed at the outlet (downstream side D2) of the rough rolling mill 10. The outlet of the rough rolling mill 10 refers to the downstream side D2 from the rough rolling mill 10 and the upstream side D1 from the rough bar cooling device 40 which is the most upstream temperature adjusting device. The rough rolling mill outlet thermometer 60 measures the temperature of the rolled material 1 at the outlet of the rough rolling mill 10 and outputs it to the processing device 80. The temperature measured by the rough rolling mill outlet thermometer 60 is also referred to as the rough rolling mill outlet temperature. The finish rolling mill outlet thermometer 70 is installed at the outlet of the finish tandem rolling mill 20. The outlet of the finish tandem rolling mill 20 refers to the downstream side D2 from the finish tandem rolling mill 20 (the most downstream rolling stand F7) and the upstream side D1 from a coiler (a device for winding the rolled material 1 after finish rolling) not shown. As a specific example of the upstream side D1 from the coiler not shown, for example, the upstream side D1 from a hot lance spray not shown for cooling the rolled material 1 after finish rolling before winding by the coiler can be mentioned. The finish rolling mill outlet thermometer 70 measures the temperature of the rolled material 1 at the outlet of the finish tandem rolling mill 20 and outputs it to the processing device 80. The temperature measured by the finish rolling mill outlet thermometer 70 is also referred to as the finish rolling mill outlet temperature.

[0018] The rough bar cooling device 40 and the cooling spray devices 51 to 56 are an example of temperature adjusting devices for adjusting the temperature of the rolled material 1 being conveyed between the outlet of the rough rolling mill 10 and the outlet of the finish tandem rolling mill 20. The rough bar cooling device 40 is installed between the rough rolling mill outlet thermometer 60 and the finish tandem rolling mill 20. The cooling spray devices 51, 52, 53, 54, 55, 56 are installed at the outlet positions of the rolling stands F1, F2, F3, F4, F5, F6 respectively. Here, the numbers 1 to 7 attached after F of the rolling stands F1 to F7 are represented using i. The outlet of the rolling stand Fi refers to the downstream side D2 from the rolling stand Fi and the upstream side D1 from the rolling stand Fi + 1. For example, the position of the outlet of the rolling stand F1 (Fi) is the downstream side D2 from the rolling stand F1 (= Fi) and the upstream side D1 from the rolling stand F2 (= Fi + 1).

[0019] The rough bar cooling device 40 and the cooling spray devices 51 to 56 are devices that adjust the flow rate of cooling water by operating the valve opening degree to supply the cooling water to the rolled material 1 and cool the rolled material 1. Note that the temperature control device is not limited to the rough bar cooling device 40 and the cooling spray devices 51 to 56. For example, only one of the rough bar cooling device 40 and the cooling spray devices 51 to 56 may be installed. Also, in addition to these temperature control devices, a temperature control device for heating the rolled material 1 may be installed at each installation position on the conveyance path R.

[0020] Here, the rough bar cooling device 40 and the cooling spray devices 51 to 56 are also referred to as the j-th temperature control device. j is an integer from 1 to 7 (7 is the total number of cooling control devices). Here, positive integers are assigned to j in ascending order from the temperature control device on the upstream side D1 in the conveyance direction D. Therefore, j = 1 is assigned to the rough bar cooling device 40 (the rough bar cooling device 40 becomes the first temperature control device). j = 2, 3, 4, 5, 6, 7 are respectively assigned to the cooling spray devices 51, 52, 53, 54, 55, 56 (the cooling spray devices 51, 52, 53, 54, 55, 56 become the second, third, fourth, fifth, sixth, and seventh temperature control devices, respectively). Note that the method of numbering a plurality of temperature control devices is not particularly limited. Also, in the following description, when referring to the (i + 1)-th temperature control device, the (i + 1)-th temperature control device indicates the cooling spray device 51, 52, 53, 54, 55, or 56 installed at the position on the outlet side of the rolling stand Fi.

[0021] The tracking device 30 continuously tracks the positions of each control point of the rolled material 1 in the conveying direction D, and generates tracking information including the position information and information indicating whether or not a certain control point of the rolled material 1 has newly reached the installation positions in the conveying direction D of the rough rolling mill exit thermometer 60, the first to seventh temperature control devices 40, 51 to 56, and the finish rolling mill exit thermometer 70, and outputs the tracking information to the processing device 80 and the first to seventh temperature control devices 40, 51 to 56. The tracking of the positions of each control point of the rolled material 1 in the conveying direction D is executed, for example, by using the rolling speed of the rough rolling mill 10, the rolling speed of the finish tandem rolling mill 20, and the conveying speed of the rolled material 1 between the rough rolling mill 10 and the finish tandem rolling mill 20. Here, "newly reached or not" does not mean whether it has reached at the current time, but means whether there has been a change in the reaching state where it did not reach in the previous sampling period of the tracking device 30 but has reached in the current sampling period. The hardware of the tracking device 30 is realized, for example, by an information processing device equipped with a processor, a main storage device, an auxiliary storage device, and various interfaces, a programmable logic controller, or dedicated hardware. In the following description, the installation position in the conveying direction D is also simply referred to as the installation position. Also, since the method itself of tracking (tracking) the position of the rolled material 1 by the tracking device 30 can be realized by a known method, the detailed description thereof is omitted here.

[0022] The processing device 80 executes processing including calculating a calculated value of the finish rolling mill exit temperature, calculating a correction amount of the finish rolling mill exit temperature based on the calculated calculated value of the finish rolling mill exit temperature and the measured value of the finish rolling mill exit temperature, and determining an operation amount of the temperature control device based on the calculated correction amount of the finish rolling mill exit temperature.

[0023] In this embodiment, a case where the processing device 80 determines the operation amounts of the first to seventh temperature control devices for each control point of the rolled material 1 will be exemplified. Therefore, the processing device 80 samples the temperature on the outlet side of the roughing mill of the rolled material 1 at each control point, which is measured by the thermometer 60 on the outlet side of the roughing mill. Further, the processing device 80 samples the temperature on the outlet side of the finishing mill of the rolled material 1 at each control point, which is measured by the thermometer 70 on the outlet side of the finishing mill. Further, the processing device 80 calculates the calculated value of the temperature on the outlet side of the finishing mill at each control point of the rolled material 1. For example, the processing device 80 calculates the calculated value of the temperature on the outlet side of the finishing mill at the control point based on the latest value of the operation amount of the temperature control device for the control point of the rolled material 1. Then, the processing device 80 calculates the correction amount of the temperature on the outlet side of the finishing mill at the control point based on the measured value of the temperature on the outlet side of the finishing mill at the control point of the rolled material 1 and the calculated value of the temperature on the outlet side of the finishing mill at the control point.

[0024] Then, the processing device 80 determines the operation amounts of the temperature control devices for each control point located on the rear end side of the rolled material 1 with respect to the control point based on the correction amount of the temperature on the outlet side of the finishing mill at the control point. For example, the processing device 80 determines the operation amounts of the temperature control devices for each control point located on the rear end side of the rolled material 1 with respect to the control point so that the temperature on the outlet side of the finishing mill corrected by the correction amount of the temperature on the outlet side of the finishing mill at the control point satisfies a predetermined temperature condition. Examples of the predetermined temperature condition include that the temperature on the outlet side of the finishing mill after correction is within a predetermined value or a predetermined range. The processing device 80 outputs the operation amount determined in this way to the temperature control device that executes the operation of the operation amount. In this embodiment, a case where the temperature control devices are the first to seventh temperature control devices 40, 51 to 56 and the operation amount is the valve opening degree will be exemplified. The hardware of the processing device 80 is realized, for example, by using an information processing device including a processor, a main storage device, an auxiliary storage device, and various interfaces, a programmable logic controller, or dedicated hardware such as an ASIC (Application Specific Integrated Circuit).

[0025] The rough bar cooling device 40 operates the valve opening degree of the rough bar cooling device 40 based on the operation amount (valve opening degree of the rough bar cooling device 40) for each control point of the rolled material 1 output from the processing device 80 and the tracking information output from the tracking device 30. The cooling spray devices 51 to 56 operate the valve opening degree of the cooling spray devices 51 to 56 based on the operation amount (valve opening degree of the cooling spray devices 51 to 56) for each control point of the rolled material 1 output from the processing device 80 and the tracking information output from the tracking device 30. In the present embodiment, a case where the temperature of the rolled material 1 is controlled as described above is exemplified.

[0026] <Functional configuration> Next, an example of the functional configuration of the processing device 80 will be described with reference to FIG. 3. In the present embodiment, a case where the processing device 80 includes an finish rolling machine exit side temperature acquisition unit 810, a rough rolling exit side temperature acquisition unit 820, an FF control unit 830 that executes processing for feedforward control of the temperature of the rolled material 1, and an FB control unit 840 that executes processing for feedback control of the temperature of the rolled material 1 is exemplified.

[0027] <Finish rolling machine exit side temperature acquisition unit 810> When the tracking information indicating that the control point of the rolled material 1 has newly reached the installation position of the finish rolling machine exit side thermometer 70 is given from the tracking device 30, the finish rolling machine exit side temperature acquisition unit 810 samples the measured value of the finish rolling machine exit side temperature at the control point of the rolled material 1 from the finish rolling machine exit side temperature measured by the finish rolling machine exit side thermometer 70. In the following description, the symbol for indicating the measured value of the finish rolling machine exit side temperature at the nth control point (n = 1 to N) of the rolled material 1 is θ F,n is denoted. n is the sampling number of the measured value of the finish rolling machine exit side temperature and is an integer from 1 to N (1 ≤ n ≤ N). In the present embodiment, since the measured values of the finish rolling machine exit side temperature at each control point of the rolled material 1 are sampled, n indicates the control point of the rolled material 1.

[0028] <Rough rolling exit side temperature acquisition unit 820> When the tracking device 30 gives tracking information that the control point of the rolled material 1 has newly reached the installation position of the roughing mill outlet thermometer 60, the roughing mill outlet temperature acquisition unit 820 samples the measurement value of the roughing mill outlet temperature at the control point of the rolled material 1 from the roughing mill outlet temperature measured by the roughing mill outlet thermometer 60. In the following description, the symbol indicating the measurement value of the roughing mill outlet temperature at the kth control point of the rolled material 1 is denoted as θ R,k Here, k is a sampling number of the measured value of the roughing mill outlet temperature, and is an integer of 1 to N (1≦k≦N). In this embodiment, the measured value of the roughing mill outlet temperature at each control point of the rolled material 1 is sampled, so k indicates the control point of the rolled material 1.

[0029] <FF制御部830> The FF control unit 830 detects the roughing mill delivery temperature θ R,k Based on this, the initial values of the operation amounts of the first to seventh temperature control devices 40, 51 to 56 for each control point are calculated. R,k This corresponds to feedforward control using the above. Such feedforward control may be realized by a known method described in Patent Document 1, for example, but in this embodiment, a case where the initial values of the manipulated variables of the first to seventh temperature control devices 40, 51 to 56 for each control point are calculated by a method using mathematical programming is illustrated. The FF control unit 830 executes such calculation of the initial value every time it is determined that each control point of the rolling material 1 has newly reached the installation position of the roughing mill delivery thermometer 60 based on the tracking information output from the tracking device 30. Below, an example of detailed functions of the FF control unit 830 will be described assuming that the kth control point of the rolling material 1 has newly reached the installation position of the roughing mill delivery thermometer 60. In this embodiment, the FF control unit 830 includes an initial value calculation unit 831 and an output unit 832.

[0030] <<Initial Value Calculation Unit 831>> The initial value calculation unit 831 calculates the measured value θ of the roughing mill delivery temperature at the kth control point of the rolling material 1. R,kBased on this, the initial values of the operation amounts of the first to seventh temperature control devices 40, 51 to 56 for the k-th control point of the rolled material 1 are calculated. Further, the initial value calculation unit 831 calculates the initial value of the calculated value of the finish rolling mill exit side temperature at the k-th control point achieved by the operation of the initial value. Hereinafter, an example of the detailed function of the initial value calculation unit 831 will be described.

[0031] First, the initial value calculation unit 831 measures the value θ of the rough rolling mill exit side temperature at the k-th control point of the rolled material 1 R,k Based on this, by performing temperature calculation for the k-th control point of the rolled material 1 when the valve opening degrees (operation amounts) of the first to seventh temperature control devices 40, 51 to 56 are each set to 0 (zero), the finish rolling mill exit side temperature T- of the rolled material 1 at the k-th control point k is calculated (predicted). Setting the operation amount of each of the first to seventh temperature control devices 40, 51 to 56 to 0 (zero) means that temperature control is not performed in all of the first to seventh temperature control devices 40, 51 to 56. Note that the symbol T- corresponds to the symbol with a - above T in the various formulas described later. In the following description, the finish rolling mill exit side temperature T- at the k-th control point k is also referred to as the reference temperature T- k . For this temperature calculation, for example, a known calculation method described in Japanese Patent Application Laid-Open No. 2008-221232 can be used.

[0032] Next, the initial value calculation unit 831 measures the value θ of the rough rolling mill exit side temperature at the k-th control point of the rolled material 1 R,k Based on this, when the valve opening degree (operation amount) of the rough bar cooling device 40 is maximized and the valve opening degrees (operation amounts) of devices other than the rough bar cooling device 40 are set to 0 (zero), the finish rolling mill exit side temperature at the k-th control point of the rolled material 1 is calculated (predicted). The initial value calculation unit 831 subtracts the reference temperature T- from the calculated finish rolling mill exit side temperature at the k-th control point k and calculates the result as the maximum temperature changeable amount ΔT of the rough bar cooling device 40 k,1 . Since the rough bar cooling device 40 is a cooling device, the value of the maximum temperature changeable amount ΔT of the rough bar cooling device 40 k,1 is negative. The maximum temperature changeable amount ΔT of the rough bar cooling device 40 k,1is the temperature difference with the largest range of change that the rough bar cooling device 40, which is the first temperature adjustment device, can adjust the finish rolling mill exit temperature at the kth control point of the rolled material 1.

[0033] In addition, the initial value calculation unit 831 calculates the roughing mill delivery temperature θ R,k Based on this, the valve opening (operation amount) of the cooling spray devices 50+i (51 (=50+1), 52 (=50+2), 53 (=50+3), 54 (=50+4), 55 (=50+5), 56 (=50+6)) installed at the exit position of the rolling stand Fi (i=1 to 6) is maximized, and the valve opening (operation amount) of the cooling spray devices other than the cooling spray device 50+i is set to 0 (zero), and the finishing mill exit temperature of the rolling material 1 at the kth control point is calculated (predicted). The initial value calculation unit 831 calculates (predicts) the reference temperature T- k The value obtained by subtracting the above is the maximum temperature change amount ΔT of the cooling spray device 50+i. k,i+1 Since the cooling spray devices 51 to 56 are cooling devices, the maximum temperature changeable amount ΔT of the cooling spray device 50+i is calculated as follows: k,i+1 The values of (i=1 to 6) are negative. Incidentally, 50+i indicates that it is one of the symbols 51, 52, 53, 54, 55, and 56 in FIG. 1 according to i (hereinafter, symbols may be represented in a similar manner). The maximum temperature changeable amount ΔT of the cooling spray device 50+i k,i+1 is the temperature difference with the largest range of change that the cooling spray device 50+i, which is the (i+1)th temperature adjustment device, can adjust the finish rolling mill delivery temperature at the kth control point of the rolled material 1. For calculating the temperature change caused by the rough bar cooling device 40 and the cooling spray devices 51-56, a known calculation method described in, for example, JP 2008-221232 A can be used.

[0034] In this manner, the reference temperature T- k and the maximum temperature change amount ΔT of the coarse bar cooling device 40 k,1 and the maximum temperature change amount ΔT of the cooling spray device 50+i (i=1 to 6) k,i+1and are calculated. Using these, the calculated value T of the temperature on the delivery side of the finishing mill at the k-th control point of the rolled material 1 k is represented by the following formula (1).

[0035]

Equation

[0036] However, x k,j is the operation ratio of the j-th temperature control device with respect to the k-th control point of the rolled material 1, and is a ratio where 0 is the case when the operation amount of the j-th temperature control device with respect to the k-th control point of the rolled material 1 is 0 (zero), and 1 is the case when the operation amount is maximum. The operation ratio of the j-th temperature control device with respect to the k-th control point of the rolled material 1 is the ratio of the temperature change of the k-th control point of the rolled material 1 when the j-th temperature control device is operated with the solved operation amount to the temperature change of the k-th control point of the rolled material 1 when the j-th temperature control device is operated with the maximum operation amount. Specifically, x k,1 is the operation ratio of the rough bar cooling device 40 with respect to the k-th control point of the rolled material 1. x k,i+1 (i = 1 to 6) is the operation ratio of the cooling spray device 50 + i with respect to the k-th control point of the rolled material 1. Since the operation amounts of the rough bar cooling device 40 and the cooling spray devices 51 to 56 are continuous values, the following formula (2) holds.

[0037]

Equation

[0038] Also, the temperature condition of keeping the temperature on the delivery side of the finishing mill at the k-th control point of the rolled material 1 within the lower limit temperature and the upper limit temperature is represented by the following inequality constraint formula (3).

[0039]

Equation

[0040] Here, d and u are the lower limit temperature and the upper limit temperature of the temperature on the outlet side of the finishing rolling mill, respectively, and are determined in advance for each rolling material 1 from the mechanical properties required for the rolling material 1. When the constraint of the lower limit temperature is not necessary, the lower limit temperature may be made small, for example, 0 °C, so that the constraint of the lower limit temperature can always be satisfied. Further, when the constraint of the upper limit temperature is not necessary, the upper limit temperature may be made large, for example, 2000 °C, so that the constraint of the upper limit temperature can always be satisfied. Further, when it is desired to make the temperature as close as possible to the target temperature of a predetermined value instead of a range having a certain temperature width of the lower limit temperature and the upper limit temperature, the target temperature may be given to the lower limit temperature and the upper limit temperature, respectively.

[0041] As described in the problem to be solved by the invention, when a temperature change occurs in the rolling material 1, the thicker the plate thickness of the rolling material 1, the less likely the shape change of the rolling material 1 occurs. Therefore, under the condition of satisfying the temperature constraint condition of Equation (3), it is desirable to use the temperature control devices installed on the upstream side D1 in the transport direction D in order. In the present embodiment, it is desirable to preferentially use the temperature control devices installed on the upstream side D1 in the transport direction D from among the rough bar cooling device 40 and the cooling spray devices 51 to 56. Therefore, in the present embodiment, as shown in the following Equation (4), an objective function J including an evaluation index for evaluating the order of use of the j-th temperature control device (the first to seventh temperature control devices) used for the k-th control point of the rolling material 1 k is used as an example.

[0042]

Equation

[0043] However, w j is a positive weight coefficient, and is preset so that w j is in ascending order (w1 < w2 < ··· < w7) with respect to the subscript j. By reducing the value of the objective function J k of Equation (4), under the condition of satisfying the temperature constraint condition of Equation (3), the cooling control devices installed on the upstream side D1 in the transport direction D can be preferentially used. Thereby, the shape change of the rolling material 1 can be made less likely to occur. The initial value calculation unit 831 calculates, within the range that satisfies the inequality constraint conditional expressions of formulas (2) and (3), the operation ratio x of the j-th temperature control device with respect to the k-th control point of the rolled material 1 at which the value of the objective function J in formula (4) is minimized. k The optimal solution x of the operation ratio x of the j-th temperature control device with respect to the k-th control point of the rolled material 1 is calculated by solving an optimization problem using mathematical programming methods, where k = 1 to N and j = 1 to 7. The solution of the optimization problem using mathematical programming methods in this embodiment is realized, for example, by using a known solver for solving a linear programming problem. Here, an example is illustrated where the initial value calculation unit 831 solves a minimization problem of minimizing the value of the objective function J in formula (4). However, for example, the initial value calculation unit 831 may solve a maximization problem. In such a case, for example, the expression obtained by multiplying the right side of formula (4) by (-1) may be used as the objective function. k,j The operation ratio x of the j-th temperature control device with respect to the k-th control point of the rolled material 1 k,j The optimal solution x of the operation ratio x of the j-th temperature control device with respect to the k-th control point of the rolled material 1 is calculated by solving an optimization problem using mathematical programming methods, where k = 1 to N and j = 1 to 7. The solution of the optimization problem using mathematical programming methods in this embodiment is realized, for example, by using a known solver for solving a linear programming problem. Here, an example is illustrated where the initial value calculation unit 831 solves a minimization problem of minimizing the value of the objective function J in formula (4). However, for example, the initial value calculation unit 831 may solve a maximization problem. In such a case, for example, the expression obtained by multiplying the right side of formula (4) by (-1) may be used as the objective function. opt,k,j (k = 1 to N, j = 1 to 7). The solution of the optimization problem using mathematical programming methods in this embodiment is realized, for example, by using a known solver for solving a linear programming problem. Here, an example is illustrated where the initial value calculation unit 831 solves a minimization problem of minimizing the value of the objective function J in formula (4). However, for example, the initial value calculation unit 831 may solve a maximization problem. In such a case, for example, the expression obtained by multiplying the right side of formula (4) by (-1) may be used as the objective function.

[0044] Based on the optimal value x of the operation ratio x of the j-th temperature control device calculated as described above, the initial value calculation unit 831 calculates the operation amount of the j-th temperature control device. k,j The optimal value x of the operation ratio x of the j-th temperature control device calculated as described above, where k = 1 to N and j = 1 to 7. opt,k,j (k = 1 to N, j = 1 to 7). Here, the temperature change of the rolled material 1 with respect to the valve opening degree z1 of the rough bar cooling device 40 can be expressed by a relationship as described in, for example, Japanese Patent Application Laid-Open No. 2008-221232. Therefore, the temperature change of the rolled material 1 at the k-th control point with respect to the valve opening degree z1 of the rough bar cooling device 40 is expressed as a function f1(z k,1 ). Let the maximum valve opening degree of the rough bar cooling device 40 be z 1max . Then, the valve opening degree z k,1 The optimal solution x of the operation ratio x of the rough bar cooling device 40 that satisfies the optimal solution x of the operation ratio x of the rough bar cooling device 40 at the k-th control point is expressed by the following formula (5). opt,k,1 (operation amount) at the k-th control point of the rough bar cooling device 40 is expressed by the following formula (5). k,1 (operation amount) is expressed by the following formula (5).

[0045]

Equation

[0046] The initial value calculation unit 831 solves equation (5) using the optimal solution x k,1 of the operation ratio x of the rough bar cooling device 40 opt,k,1 to calculate the valve opening degree z k,1 (k = 1 to N) of the rough bar cooling device 40 for the k-th control point of the rolled material 1 as the feedforward operation amount. Similar to the temperature change at the k-th control point of the rolled material 1 with respect to the valve opening degree z1 of the rough bar cooling device 40, the temperature change at the k-th control point of the rolled material 1 with respect to the valve opening degree z i+1 of the cooling spray device 50 + i installed at the outlet side (i = 1 to 6) of the rolling stand Fi is represented by the function f i+1 (z i+1 ). Assuming the maximum valve opening degree of the cooling spray device 50 + i is z (i+1)max , the valve opening degree z k,i+1 of the cooling spray device 50 + i that satisfies the optimal solution x opt,k,i+1 of the operation ratio x k,i+1 (operation amount) is represented by the following equation (6).

[0047]

Equation

[0048] The initial value calculation unit 831 solves equation (6) using the optimal solution x k,i+1 of the operation ratio x of the cooling spray device 50 + i opt,k,i+1 to calculate the valve opening degree z k,i+1 (k = 1 to N, i = 1 to 6) of the cooling spray device 50 + i for the k-th control point of the rolled material 1 as the feedforward operation amount. The initial value calculation unit 831 executes feedback control after obtaining the measured value of the temperature at the outlet side of the finishing mill at the k-th control point of the rolled material 1. Therefore, the valve opening degrees z k,1 , z k,i+1 (k = 1 to N, i = 1 to 6) of the first to seventh temperature control devices 40, 51 to 56 calculated by equations (5) and (6) are used as the initial values z (0) k,j of the valve opening degrees (operation amounts) of the respective temperature control devices 40, 51 to 56 for the k-th control point.Let (k = 1 to N, j = 1 to 7). Also, the initial value calculation unit 831 initializes the initial value δ of the correction amount δ of the temperature on the outlet side of the finishing rolling mill to 0 (zero) (δ (0) = 0). Further, the initial value calculation unit 831 substitutes the optimal solution x (0) of the operation ratios x k,j of the first to seventh temperature control devices 40, 51 to 56 (k = 1 to N, j = 1 to 7), the maximum temperature changeable amount ΔT opt,k,j of the first to seventh temperature control devices 40, 51 to 56 (k = 1 to N, j = 1 to 7), and the reference temperature T- k,j into equation (1) to calculate the initial value T k of the calculated value T k of the temperature on the outlet side of the finishing rolling mill at the k-th control point of the rolled material 1. The initial value T (0) cal,k of the calculated value T k of the temperature on the outlet side of the finishing rolling mill at the k-th control point of the rolled material 1 is the calculated value of the temperature on the outlet side of the finishing rolling mill at the k-th control point of the rolled material 1 achieved by operating each temperature control device 40, 51 to 56 with the initial value z (0) cal,k of the valve opening degree (operation amount) of each temperature control device 40, 51 to 56 with respect to the k-th control point of the rolled material 1 (j = 1 to 7). Note that the symbol z (0) k,j corresponds to the symbol with (0) above the horizontal line of z and k, j arranged below in the various equations described later. Also, the symbol T (0) k,j corresponds to the symbol with (0) above the horizontal line of T and cal, k arranged below in the various equations described later. (0) cal,k

[0049] <<Output unit 832>> The output unit 832 outputs the valve opening degree z k,j of the j-th temperature control device with respect to the k-th control point of the rolled material 1 calculated by the initial value calculation unit 831 (k = 1 to N, j = 1 to 7) to the j-th temperature control device. When the j-th temperature control device acquires tracking information indicating that the k-th control point of the rolled material 1 has newly reached its installation position from the tracking device 30, it sets its valve opening degree to the valve opening degree z k,j ​Change to this. At this time, until the first control point at the leading end of the rolled material 1 reaches the installation position of the thermometer 70 on the outlet side of the finishing rolling mill, the feedback control by the FB control unit 840 described later is not executed. Therefore, the valve opening degrees z k,j (k = 1 to N, j = 1 to 7) used in each temperature control device 40, 51 to 56 are the initial values z (0) k,j (k = 1 to N, j = 1 to 7), that is, equal to the valve opening degree z k,j (k = 1 to N, j = 1 to 7) output from the output unit 832. Further, the output unit 832 outputs various initial values calculated by the initial value calculation unit 831, the maximum temperature changeable amount ΔT k,j (k = 1 to N, j = 1 to 7), and the reference temperature T- k (k = 1 to N) to the FB control unit 840. As described above, the initial values calculated by the initial value calculation unit 831 are the initial values z of the valve opening degrees (operation amounts) of the temperature control devices 40, 51 to 56 with respect to the k-th control point of the rolled material 1 (0) k,j (k = 1 to N, j = 1 to 7), the initial value δ of the correction amount δ of the temperature on the outlet side of the finishing rolling mill, and the calculated value T of the temperature on the outlet side of the finishing rolling mill at the k-th control point of the rolled material 1 (0) k The initial value T of (0) cal,k (k = 1 to N).

[0050] <FB control unit 840> When the FB control unit 840 obtains the measured value θ of the temperature on the outlet side of the finishing rolling mill at the n-th control point of the rolled material 1 F,n the valve opening degrees (operation amounts) z of the first to seventh temperature control devices with respect to the control points located on the rear end side (upstream side D1) of the rolled material 1 from the n-th control point, that is, the k-th control points satisfying k>n k,j ​The FB control unit 840 determines the valve opening (operation amount) in this manner based on the tracking information output from the tracking device 30, each time it is determined that the nth control point (n=1 to N) of the rolling material 1 has newly reached the installation position of the finishing rolling mill delivery thermometer 70. Below, detailed functions of the FB control unit 840 will be described assuming that the nth control point of the rolling material 1 has newly reached the installation position of the finishing rolling mill delivery thermometer 70. In this embodiment, the FB control unit 840 includes a temperature calculation unit 841, a correction amount calculation unit 842, an operation amount determination unit 843, and an output unit 844.

[0051] <<Temperature calculation section 841>> When the measured value of the temperature on the delivery side of the finishing rolling mill is obtained, the temperature calculation unit 841 calculates the latest value z of the operation amount of the temperature adjustment device for the n-th control point of the rolling material 1. n,j Based on this, a calculated value of the finish rolling mill outlet temperature for the nth control point of the rolled material 1 is calculated. As described above, in this embodiment, a case is exemplified in which the processing device 80 determines the operation amount of each temperature adjustment device 40, 51 to 56 for each control point of the rolled material 1. Thus, when a measured value of the finish rolling mill outlet temperature at the nth control point of the rolled material 1 is obtained, the temperature calculation unit 841 calculates a calculated value of the finish rolling mill outlet temperature at the nth control point of the rolled material 1. An example of the detailed functions of the temperature calculation unit 841 will be described below.

[0052] The valve opening (operation amount) of each of the temperature control devices 40, 51 to 56 for the n-th control point of the rolling material 1 is set to the initial value z (0) n,j The calculated temperature of the finishing mill at the nth control point of the rolling material 1 when (n=1 to N, j=1 to 7) is T (0) cal,n However, the measured values θ of the finishing mill exit temperature at the 1st to (n-1st) control points on the front end side (downstream side D2) of the nth control point of the rolling material 1 are F,1 ~θ F,n-1When obtained, the valve opening degrees of the respective temperature control devices 40 and 51 to 56 for the n-th control point of the rolled material 1 may be updated by feedback control by the FB control unit 840 described below. Therefore, it is necessary to recalculate the calculated value of the temperature on the outlet side of the finishing mill at the n-th control point of the rolled material 1.

[0053] In this embodiment, the calculated value T of the temperature on the outlet side of the finishing mill at the n-th control point of the rolled material 1 cal,n is the initial value T of the calculated value of the temperature on the outlet side of the finishing mill at the n-th control point of the rolled material 1 (0) cal,n and the initial value z of the operation amount of each temperature control device for the n-th control point of the rolled material 1 (0) n,j and the maximum temperature changeable amount ΔT n,j (j = 1 to 7) and the latest value z of the operation amount of the temperature control device for the n-th control point of the rolled material 1 n,j are used as an example. The symbol indicating the latest value of the valve opening degree (operation amount) of each temperature control device 40 and 51 to 56 for the n-th control point of the rolled material 1 is z n,j (n = 1 to N, j = 1 to 7). The operation ratio x of each temperature control device 40 and 51 to 56 for the n-th control point of the rolled material 1 when the valve opening degree is the latest value z n,j is represented by the following formula (7). Also, the operation ratio x of each temperature control device 40 and 51 to 56 for the n-th control point of the rolled material 1 when the valve opening degree of each temperature control device 40 and 51 to 56 for the n-th control point of the rolled material 1 is the initial value z n,j (n = 1 to N, j = 1 to 7) is represented by the following formula (8). Note that the symbol x (0) n,j corresponds to the symbol with (0) above x and n, j arranged below in each formula. (0) n,j (n = 1 to N, j = 1 to 7) is represented by the following formula (8). Note that the symbol x (0) n,j corresponds to the symbol with (0) above x and n, j arranged below in each formula.

[0054]

Equation

[0055] The x in formula (7) n,j and the x in formula (8) (0) n,j Using these, from formula (1), the calculated value T of the finish rolling mill exit side temperature for the n-th control point of the rolled material 1 cal,n is represented by the following formula (9).

[0056]

Equation

[0057] The second term on the right side of formula (9) represents the change in the initial value T of the calculated value of the finish rolling mill exit side temperature at the n-th control point of the rolled material 1 when the operation ratios of the respective temperature control devices 40, 51 to 56 for the n-th control point of the rolled material 1 are changed from x (0) n,j to x n,j to the calculated value of the finish rolling mill exit side temperature at the n-th control point of the rolled material 1 when the operation ratios of the respective temperature control devices 40, 51 to 56 for the n-th control point of the rolled material 1 are changed from x (0) cal,n to the calculated value of the finish rolling mill exit side temperature at the n-th control point of the rolled material 1 when the operation ratios of the respective temperature control devices 40, 51 to 56 for the n-th control point of the rolled material 1 are changed from x The temperature calculation unit 841 calculates the operation ratio x of the respective temperature control devices 40, 51 to 56 for the n-th control point of the rolled material 1 when the valve opening degrees of the respective temperature control devices 40, 51 to 56 for the n-th control point of the rolled material 1 are the latest value z n,j by formula (7). Also, the temperature calculation unit 841 calculates the operation ratio x of the respective temperature control devices 40, 51 to 56 for the n-th control point of the rolled material 1 when the valve opening degrees of the respective temperature control devices 40, 51 to 56 for the n-th control point of the rolled material 1 are the initial value z n,j by formula (8). Then, the temperature calculation unit 841 substitutes these calculated values (x (0) k,j (0) n,j n,j (0) n,j (0) cal,n cal,n ) and the initial value T of the calculated value of the finish rolling mill exit side temperature at the n-th control point of the rolled material 1 into formula (9). Thereby, the calculated value T of the finish rolling mill exit side temperature at the n-th control point of the rolled material 1 (0) cal,n is calculated. cal,n is calculated.

[0058] <<Correction amount calculation unit 842>> The correction amount calculation unit 842 calculates a correction amount for the finish rolling mill delivery temperature based on the measured value of the finish rolling mill delivery temperature and the calculated value of the finish rolling mill delivery temperature calculated by the temperature calculation unit 841. In this embodiment, the correction amount calculation unit 842 calculates a correction amount for the finish rolling mill delivery temperature based on the measured value θ F,n and the calculated value T of the finishing mill delivery temperature at the nth control point of the rolling material 1 calculated by the temperature calculation unit 841. cal,n Based on this, the correction amount δ of the finish rolling mill delivery temperature at the nth control point of the rolling material 1 is calculated. (n) The correction amount calculation unit 842 calculates the correction amount δ of the finish rolling mill delivery temperature at the n-th control point of the rolling material 1, for example, by the following formula (10): (n) Calculate.

[0059]

number

[0060] Here, a is the correction amount δ of the finish rolling mill delivery temperature at the nth control point of the rolling material 1. (n) This is a smoothing gain to suppress large changes in the smoothing gain a at once. The smoothing gain a value should be greater than 0 and less than 1 (0 <a<1)が予め設定される。

[0061] <<Operation amount determination unit 843>> The operation amount determination unit 843 determines the correction amount δ of the finishing mill delivery temperature calculated and updated by the correction amount calculation unit 842. (n) Based on this, the measured value θ of the temperature at the exit of the finishing mill F,n In this embodiment, the operation amount determination unit 843 determines the operation amount of the temperature adjustment device for the rolled material 1 obtained by the n-th control point. (n) Based on this, the manipulated variable for the temperature adjustment device for the kth control point (k=n+1 to N) located on the rear end side of the rolled material 1 relative to the nth control point is determined. An example of the detailed functions of the manipulated variable determiner 843 will be described below. The calculated temperature at the exit of the finishing mill, T, is calculated using the formula (1). kis corrected using the correction amount δ of the finishing rolling mill outlet side temperature shown in formula (10). (n) When corrected using this, the finishing rolling mill outlet side temperature T at the k-th control point (k = n + 1 to N) of the rolled material 1 k is represented by the following formula (11).

[0062] [Number]

[0063] The operation amount determination unit 843, within the range that satisfies the inequality constraint conditional expressions of formulas (2) and (3), determines the operation ratio x of the j-th temperature adjustment device with respect to the k-th control point of the rolled material 1 at which the value of the objective function J k is minimized. The optimal solution x k,j of the operation ratio x of the j-th temperature adjustment device with respect to the k-th control point of the rolled material 1 k,j is calculated by solving the optimization problem using mathematical programming methods as the optimal solution x opt,k,j (k = n + 1 to N, j = 1 to 7). In the process in the initial value calculation unit 831, T represented by formula (1) is used as T k in formula (3). In contrast, in the process in the operation amount determination unit 843, T represented by formula (11) is used as T k in formula (3). Also, in the process in the initial value calculation unit 831, the k for which the optimal solution x k is calculated when the rough rolling mill outlet side temperature θ of the k-th control point k is obtained is one of the control points k at which the rough rolling mill outlet side temperature is measured. In contrast, in the process in the operation amount determination unit 843, the k for which the optimal solution x R,k is calculated when the finishing rolling mill outlet side temperature θ of the n-th control point opt,k,j is obtained is the control points n + 1 to N on the rear end side of the control points at which the finishing rolling mill outlet side temperature is measured. Note that also in the operation amount determination unit 843, as described in the section of <<Initial value calculation unit 831>>, the objective function J F,n may be configured so as to solve a maximization problem instead of a minimization problem. opt,k,j k

[0064] ​​The operation amount determination unit 843 calculates the operation ratio x of each of the temperature control devices 40 and 51 to 56 with respect to the k-th control point of the rolled material 1 k,j of the optimal solution x opt,k,j By solving the following equation (12) using, the valve opening degree z of the temperature control devices 40 and 51 to 56 with respect to the k-th control point of the rolled material 1 k,j (k = n + 1 to N, j = 1 to 7) is calculated and updated. In this embodiment, in this way, the valve opening degree z of each of the temperature control devices 40 and 51 to 56 when controlling the temperature of the k-th control point of the rolled material 1 k,j is calculated as the latest value of the operation amount.

[0065]

Equation

[0066] <<Output unit 844>> The output unit 844 outputs the valve opening degree z of the j-th temperature control device with respect to the k-th control point of the rolled material 1 calculated and updated by the operation amount determination unit 843 k,j (k = n + 1 to N, j = 1 to 7) to the j-th temperature control device. The j-th temperature control device replaces the valve opening degree z k,j output from the output unit 832 of the FF control unit 830 (feedforward control) with the valve opening degree z k,j output from the output unit 844 of the FB control unit 840 (feedback control), and when acquiring tracking information from the tracking device 30 indicating that the k-th control point (k = n + 1 to N) of the rolled material 1 has newly reached its installation position, changes the valve opening degree to that value. As a result, feedback control using the measured value θ F,n of the finish rolling mill outlet side temperature at the n-th control point of the rolled material 1 is realized.

[0067] <Flowchart> Next, an example of the feedforward control process by the processing device 80 (FF control unit 830) will be described with reference to the flowchart of FIG. 4. First, in step S401, the FF control unit 830 sets an initial value (= 1) for a variable k (sampling number of the rough rolling mill outlet side temperature) that identifies the control point of the rolled material 1. Next, in step S402, the rough rolling mill outlet side temperature acquisition unit 820 acquires the measured value θ of the rough rolling mill outlet side temperature at the k-th control point of the rolled material 1. R,k to obtain.

[0068] Next, in step S403, the initial value calculation unit 831 calculates, based on the measured value θ of the rough rolling mill outlet side temperature at the k-th control point of the rolled material 1, the finish rolling mill outlet side temperature T- at the k-th control point of the rolled material 1 when the valve opening degrees (operation amounts) of the respective temperature adjustment devices 40, 51 to 56 are set to 0 (zero). R,k as the reference temperature T-. k as the reference temperature T-. k and calculates it. Next, in step S404, the initial value calculation unit 831 individually calculates (predicts) for each of the temperature adjustment devices 40, 51 to 56 the finish rolling mill outlet side temperature at the k-th control point of the rolled material 1 when the valve opening degree (operation amount) of any one of the temperature adjustment devices 40, 51 to 56 is maximized and the valve opening degrees (operation amounts) of the remaining ones are set to 0 (zero), based on the rough rolling mill outlet side temperature θ at the k-th control point of the rolled material 1. Then, the initial value calculation unit 831 subtracts the reference temperature T- from the calculated finish rolling mill outlet side temperature at the k-th control point, and calculates the maximum temperature changeable amount ΔT R,k of each of the temperature adjustment devices 40, 51 to 56. k of each of the temperature adjustment devices 40, 51 to 56 as the value obtained by subtracting the reference temperature T- from the calculated finish rolling mill outlet side temperature at the k-th control point. k,j (j = 1 to 7).

[0069] Next, in step S405, the initial value calculation unit 831 calculates, within the range satisfying the inequality constraint conditional expressions of equations (2) and (3), the operation ratio x k of the j-th temperature adjustment device for the k-th control point of the rolled material 1 at which the value of the objective function J k,j of the rolled material 1 is minimized, as the optimal solution x k,j of the operation ratio x opt,k,j (j = 1 to 7) of the j-th temperature adjustment device for the k-th control point of the rolled material 1. Next, in step S406, the initial value calculation unit 831 solves equation (5) using the optimal solution x k,1 of the operation ratio x opt,k,1 of the rough bar cooling device 40, and thereby determines the valve opening degree z k,1is calculated. Further, the initial value calculation unit 831 calculates the operation ratio x of the cooling spray device 50+i k,i+1 of the optimal solution x opt,k,i+1 is used to solve equation (6) to calculate the valve opening degree z of the cooling spray device 50+i for the k-th control point of the rolled material 1 k,i+1 (i = 1 to 6). In this way, the operation ratio x of the j-th temperature control device for the k-th control point of the rolled material 1 calculated in step S405 k,j of the optimal solution x opt,k,j corresponding to the valve opening degree z of the j-th temperature control devices 40, 51 to 56 k,j (j = 1 to 7) is calculated.

[0070] Next, in step S407, the output unit 832 outputs the valve opening degree z of the j-th temperature control devices 40, 51 to 56 for the k-th control point of the rolled material 1 calculated in step S406 k,j (j = 1 to 7) to the j-th temperature control device. Next, in step S408, the initial value calculation unit 831 sets the valve opening degree z of each temperature control device 40, 51 to 56 calculated in step S406 k,j as the initial value z of the valve opening degree of each temperature control device 40, 51 to 56 for the k-th control point (0) k,j (j = 1 to 7). Further, the initial value calculation unit 831 initializes the initial value δ of the correction amount δ of the temperature on the outlet side of the finishing rolling mill to 0 (zero) (δ (0) = 0). (0)

[0071] Next, in step S409, the initial value calculation unit 831 substitutes the optimal solution x of the operation ratio x of each temperature control device 40, 51 to 56 k,j into equation (1) to calculate the calculated value T of the temperature on the outlet side of the finishing rolling mill at the k-th control point of the rolled material 1 opt,k,j of the initial value T k (0) cal,k (0) .

[0072] Next, in step 410, the output unit 832 outputs the initial value z calculated by the initial value calculation unit 831 (0) k,j(k = 1 to N, j = 1 to 7), δ (0) 、T (0) cal,k (k = 1 to N) and the maximum temperature changeable amount ΔT k,j (k = 1 to N, j = 1 to 7) and the reference temperature T- k (k = 1 to N) are output to the FB control unit 840.

[0073] Next, in step S411, the FF control unit 830 determines whether the variable k is equal to N. As a result of this determination, if the variable k is not N (NO in step S411), since the processing by the FF control unit 830 for all the control points of the rolled material 1 has not been completed, the processing proceeds to step S412. In step S412, the FF control unit 830 adds 1 to the value of the variable k to update the variable k. Then, the processing of steps S402 to S411 is executed for the updated k-th control point. And when it is determined in step S411 that the variable k is N (YES in step S411), the processing according to the flowchart of FIG. 4 ends.

[0074] Next, an example of the feedback control process by the processing device 80 (FB control unit 840) will be described with reference to the flowchart of FIG. 5. First, in step S501, the FB control unit 840 sets an initial value (= 1) to the variable n (sampling number of the finish rolling mill exit side temperature) that identifies the control point of the rolled material 1. Next, in step S502, the FB control unit 840 receives the initial value z output from the FF control unit 830 in step S410 of FIG. 4 (0) k,j (k = 1 to N, j = 1 to 7), δ (0) 、T (0) cal,k (k = 1 to N) and the maximum temperature changeable amount ΔT k,j (k = 1 to N, j = 1 to 7) and the reference temperature T- k (k = 1 to N) and obtains them.

[0075] Next, in step S503, the finish rolling mill exit side temperature acquisition unit 810 measures the measured value θ of the finish rolling mill exit side temperature at the n-th control point of the rolled material 1F,n to obtain Next, in step S504, the FB control unit 840 obtains the latest values z of the valve opening degrees (operation amounts) of the respective temperature adjustment devices 40, 51 to 56 with respect to the n-th control point of the rolled material 1 n,j (j = 1 to 7) from the respective temperature adjustment devices 40, 51 to 56.

[0076] Next, in step S505, the temperature calculation unit 841 calculates the operation ratios x of the respective temperature adjustment devices 40, 51 to 56 with respect to the n-th control point of the rolled material 1 when the valve opening degrees of the respective temperature adjustment devices 40, 51 to 56 with respect to the n-th control point of the rolled material 1 are the latest values z n,j (j = 1 to 7) according to equation (7). n,j (j = 1 to 7) are calculated by equation (7). Next, in step S506, the temperature calculation unit 841 calculates the operation ratios x of the respective temperature adjustment devices 40, 51 to 56 with respect to the n-th control point of the rolled material 1 when the valve opening degrees of the respective temperature adjustment devices 40, 51 to 56 with respect to the n-th control point of the rolled material 1 are the initial values z (0) n,j (j = 1 to 7) according to equation (8). (0) n,j (j = 1 to 7) are calculated by equation (8).

[0077] Next, in step S507, the temperature calculation unit 841 substitutes the values (x n,j , x (0) n,j ) calculated in steps S505 and S506, the initial value T of the calculated value of the temperature on the exit side of the finishing mill at the n-th control point of the rolled material 1 obtained in step S502 (0) cal,n and the maximum temperature changeable amount ΔT n,j (j = 1 to 7) into equation (9) to calculate the calculated value T of the temperature on the exit side of the finishing mill at the n-th control point of the rolled material 1. cal,n to calculate Next, in step S508, the correction amount calculation unit 842 calculates the measured value θ of the temperature on the exit side of the finishing mill at the n-th control point of the rolled material 1 obtained in step S503 F,n and the calculated value T of the temperature on the exit side of the finishing mill at the n-th control point of the rolled material 1 calculated in step S507 cal,nUsing (10), the correction amount δ of the temperature on the exit side of the finishing rolling mill at the n-th control point of the rolled material 1 is calculated according to the formula. (n) is calculated.

[0078] Next, in step S509, the operation amount determination unit 843, within the range satisfying the inequality constraint conditions of equations (2) and (3), determines the operation ratio x of the j-th temperature control device for the k-th control point of the rolled material 1 such that the value of the objective function J in equation (4) k is minimized. k,j For the operation ratio x of the j-th temperature control device with respect to the k-th control point of the rolled material 1 k,j The optimal solution x opt,k,j (k = n + 1 to N, j = 1 to 7) is calculated. Here, among the maximum temperature changeable amounts ΔT k,j (k = 1 to N, j = 1 to 7) obtained in step S502, the maximum temperature changeable amount ΔT for k = n + 1 to N, j = 1 to 7 k,j is used. Also, among the reference temperatures T- k (k = 1 to N) obtained in step S502, the reference temperature T- for k = n + 1 to N k is used. Next, in step S510, the operation amount determination unit 843 solves equation (12) using the optimal solution x of the operation ratio x of each temperature control device 40, 51 to 56 with respect to the k-th control point of the rolled material 1 k,j The optimal solution x opt,k,j to calculate and update the valve opening degree z of each temperature control device 40, 51 to 56 corresponding to the optimal solution x of the operation ratio x of each temperature control device 40, 51 to 56 with respect to the k-th control point of the rolled material 1 k,j The optimal solution x opt,k,j (k = n + 1 to N, j = 1 to 7). k,j (k = n + 1 to N, j = 1 to 7) is calculated and updated.

[0079] Next, in step S511, the output unit 844 outputs the valve opening degree z of the j-th temperature control device with respect to the k-th control point of the rolled material 1 calculated in step S510 k,j (k = n + 1 to N, j = 1 to 7) to each of the j-th temperature control devices. Next, in step S512, the FB control unit 840 determines whether the variable n is equal to N. As a result of this determination, if the variable n is not N (NO in step S512), since the processing by the FB control unit 840 for all the control points of the rolled material 1 has not been completed, the process proceeds to step S513. In step S513, the FB control unit 840 updates the variable n by adding 1 to the value of the variable n. Then, the processing from steps S502 to S512 is executed for the updated n-th control point. When it is determined in step S512 that the variable n is N (YES in step S512), the processing according to the flowchart of FIG. 5 ends.

[0080] <Summary> As described above, in the present embodiment, the processing device 80 measures the value θ of the temperature on the outlet side of the finishing rolling mill F,n and the calculated value T of the temperature on the outlet side of the finishing rolling mill cal,n Based on this, the correction amount δ of the temperature on the outlet side of the finishing rolling mill is calculated (n) Based on the correction amount δ of the temperature on the outlet side of the finishing rolling mill (n) Similar to the case of performing feedforward control, the manipulated variables z of the temperature control devices 40, 51 to 56 are determined so that the objective function of equation (4) is minimized k,j Therefore, this feedback control can be operated from the temperature control device on the upstream side. Also, unlike the method of performing feedback control based on the temperature deviation between the measured value and the target value of the temperature on the outlet side of the finishing rolling mill, feedback control can be executed without being affected by the dead time. Therefore, when controlling the temperature on the outlet side of the finishing rolling mill, it is possible to achieve both suppression of shape deterioration of the rolled material and high responsiveness of temperature control.

[0081] Also, in the present embodiment, the processing device 80 measures the value θ of the temperature on the outlet side of the rough rolling mill R,n The calculated value T of the temperature on the outlet side of the finishing rolling mill at the n-th control point where is acquired cal,n Based on the latest value z of the manipulated variables of the temperature control devices 40, 51 to 56 n,j Based on this, the correction amount δ of the temperature on the outlet side of the finishing rolling mill is calculated (n) Then, the processing device 80 calculates the correction amount δ of the temperature on the outlet side of the finishing rolling mill (n)The finish rolling mill outlet side temperature T corrected thereby k is such that the temperature control devices 40, 51 to 56 are operated so as to satisfy a predetermined temperature condition (for example, d < T k <u). Accordingly, as the finish rolling mill outlet side temperature that greatly affects the quality of the rolled material 1, a correction amount δ that reflects the state of the rolled material 1 on the downstream side of the finish tandem rolling mill 20 as feedback k,j is used to determine the operation amount z of the temperature control devices 40, 51 to 56 for the finish rolling mill outlet side temperature T corrected by (n) it. Accordingly, the operation amount z of the temperature control devices 40, 51 to 56 can be determined using the finish rolling mill outlet side temperature T corrected by the correction amount δ k . k,j

[0082] Also, in the present embodiment, the processing device 80 calculates a correction amount δ of the finish rolling mill outlet side temperature at the n-th control point based on the measured value θ F,n of the finish rolling mill outlet side temperature at the n-th control point and the calculated value T cal,n of the finish rolling mill outlet side temperature at the n-th control point. Then, the processing device 80 determines the operation amount z (n) of the temperature control device for the k-th control point (k = n + 1 to N) located on the rear end side of the n-th control point based on the correction amount δ (n) of the finish rolling mill outlet side temperature at the n-th control point. Accordingly, the finish rolling mill outlet side temperature can be controlled for each control point. Therefore, depending on the setting interval of the control points, it is possible to prioritize reducing the calculation load or to prioritize performing highly accurate control k,j .

[0083] Also, in the present embodiment, the processing device 80 calculates an initial value z R,k of the operation amount of the temperature control devices 40, 51 to 56 for the k-th control point based on the measured value θ (0) k,j (j = 1 to 7) of the rough rolling mill outlet side temperature at the k-th control point of the rolled material 1 and an initial value T (0) cal,k of the calculated value of the finish rolling mill outlet side temperature at the k-th control point achieved by the operation of the initial value. Then, the processing device 80 measures the finish rolling mill outlet side temperature at the n-th control point of the rolled material 1 F,n ​Once obtained, the initial value T of the calculated value of the temperature on the outlet side of the finishing rolling mill at the nth control point (0) cal,n and the initial value z of the operation amount of the temperature control devices 40, 51 to 56 for the nth control point (0) n,j and the latest value z of the operation amount of the temperature control devices 40, 51 to 56 for the nth control point n,j are used to calculate the calculated value T of the temperature on the outlet side of the finishing rolling mill at the nth control point cal,n . Therefore, since it is only necessary to calculate the correction amount for the initial value z of the operation amount of the temperature control devices 40, 51 to 56 for the nth control point, the load of the predictive calculation of the temperature on the outlet side of the finishing rolling mill can be reduced (0) n,j As described above, the feedback control executed by the FB control unit 840 in the present embodiment does not correct the operation amount of the temperature control devices 40, 51 to 56 based on the deviation between the measured value and the target value of the temperature on the outlet side of the finishing rolling mill, as in the techniques disclosed in Patent Documents 2 and 3. Instead, the measured value θ of the temperature on the outlet side of the finishing rolling mill at the nth control point where the temperature sensor 70 on the outlet side of the finishing rolling mill reaches

[0084] and the calculated value T of the temperature on the outlet side of the finishing rolling mill represented by the formula (9) F,n are used to calculate the correction amount δ of the temperature on the outlet side of the finishing rolling mill cal,n and update it (from δ (n) ), and the correction amount δ of the temperature on the outlet side of the finishing rolling mill is used to determine the operation amount of each temperature control device 40, 51 to 56 for each control point located on the rear end side of the rolled material 1 with respect to the nth control point. The essential difference from feedforward control in determining the operation amount of each temperature control device 40, 51 to 56 is that T in the formula (1) in feedforward control (n-1) is, in feedback control, as in the formula (11), the measured value θ of the temperature on the outlet side of the finishing rolling mill is corrected by the correction amount δ of the temperature on the outlet side of the finishing rolling mill (n) and the operation amount of each temperature control device 40, 51 to 56 for each control point located on the rear end side of the rolled material 1 with respect to the nth control point is determined. The essential difference from feedforward control in determining the operation amount of each temperature control device 40, 51 to 56 is that T in the formula (1) in feedforward control k is, in feedback control, as in the formula (11), the measured value θ of the temperature on the outlet side of the finishing rolling mill is corrected by the correction amount δ of the temperature on the outlet side of the finishing rolling mill (n) and the operation amount of each temperature control device 40, 51 to 56 for each control point located on the rear end side of the rolled material 1 with respect to the nth control point is determined. The essential difference from feedforward control in determining the operation amount of each temperature control device 40, 51 to 56 is that T in the formula (1) in feedforward control F,nIt is corrected to match. Also, the method for determining the operation amounts of the temperature control devices 40 and 51 to 56 during feedback control is the same as that for feedforward control (refer to equations (2) to (4)). Therefore, in the feedback control in this embodiment, as in the case of performing feedforward control conventionally, the temperature control devices can be used from the upstream side, so that the shape deterioration of the rolled material 1 can be suppressed. Further, the method of this embodiment is not a method of performing feedback control based on the deviation between the measured value and the target value, like the methods disclosed in Patent Documents 2 and 3. Therefore, feedback control can be executed without being affected by dead time, and high responsiveness of temperature control can be achieved. Also, when controlling so that the temperature on the outlet side of the finishing rolling mill is equal to or higher than the lower limit temperature and equal to or lower than the upper limit temperature, if the feedback control described in Patent Documents 2 and 3 is applied, the temperature deviation will be obtained with a dead zone between the lower limit temperature and the upper limit temperature. Therefore, the operation amounts of the temperature control devices 40 and 51 to 56 are not changed until the measured value θ F,n of the temperature on the outlet side of the finishing rolling mill deviates from the upper and lower limit temperatures, and there arises a problem that the response becomes slow. On the other hand, in the method of this embodiment, even when controlling so that the temperature on the outlet side of the finishing tandem rolling mill is equal to or higher than the lower limit temperature and equal to or lower than the upper limit temperature (refer to equation (3)), the correction amount δ (n) of the temperature on the outlet side of the finishing rolling mill is calculated and updated without setting a dead zone between the lower limit temperature and the upper limit temperature. Therefore, the operation amounts of the temperature control devices 40 and 51 to 56 can be changed even if the measured value θ F,n of the temperature on the outlet side of the finishing rolling mill does not deviate from the upper and lower limit temperatures.

[0085] <Modification Example> In this embodiment, during the feedback control by the FB control unit 840, the optimum solution x k,j of the operation ratio x opt,k,j of all the temperature control devices 40 and 51 to 56 is calculated, and the valve opening degree z k,j of all the temperature control devices 40 and 51 to 56 is set to the optimum solution x opt,k,jThe case of changing to a value according to [a certain condition] was exemplified. However, among the temperature control devices 40, 51 to 56, even if the operation amount of the temperature control device through which the k-th control point of the rolled material 1 has already passed is changed, the temperature at the k-th control point cannot be changed. Therefore, it is preferable to change only the operation amount of the temperature control device through which the k-th control point has not yet passed. In this case, for example, the following may be done. In the present embodiment, the processing device 80 is given tracking information representing the positions of the respective control points of the rolled material 1 from the tracking device 30. Therefore, the operation amount determination unit 843 specifies a temperature control device located on the downstream side D2 (the tip side of the rolled material 1) from the position where the k-th control point exists, based on the tracking information. The operation amount determination unit 843 calculates the subscript m(k) corresponding to j of the operation ratio x k,j corresponding to the operation amount of the temperature control device located most upstream (the most rear end side of the rolled material 1) among them. In the present embodiment, when the temperature control device located most upstream is the first temperature control device (rough bar cooling device 40), m(k)=1, and when it is the (i + 1)-th temperature control device (cooling spray device 50 + i, i = 1 to 6), m(k)=i + 1. Using m(k), equation (11) is expressed as the following equation (13).

[0086]

Equation

[0087] In equation (13), x k,j (k = n + 1 to N, j = 1 to m(k) - 1) is the operation ratio of the temperature control device located on the upstream side D1 (the temperature control device through which the k-th control point of the rolled material 1 has already passed) from the position where the k-th control point of the rolled material 1 exists. The operation amount determination unit 843 does not update the valve opening degree (operation amount) z k,j (k = n + 1 to N, j = 1 to m(k) - 1) of the temperature control device located on the upstream side D1 from the position where the k-th control point of the rolled material 1 exists. Therefore, the operation amount determination unit 843 sets the operation ratio x k,j (k = n + 1 to N, j = 1 to m(k) - 1) of the temperature control device located on the upstream side D1 from the position where the k-th control point of the rolled material 1 exists to the latest value z of the valve opening degree (operation amount) of the said temperature control device k,jRecalculate using the following formula (14) with (k = n + 1 to N, j = 1 to m(k) - 1). On the other hand, x k,j (k = n + 1 to N, j = m(k) to 7) is the operation ratio of the temperature control device (the temperature control device through which the k-th control point of the rolled material 1 has not yet passed) on the downstream side D2 from the position where the k-th control point of the rolled material 1 exists. The operation amount determination unit 843 is the operation ratio x of the temperature control device on the downstream side from the position where the k-th control point of the rolled material 1 exists k,j The optimal solution x of opt,k,j (k = n + 1 to N, j = m(k) to 7) is calculated by solving the optimization problem using mathematical programming methods. At this time, the operation amount determination unit 843 is the operation ratio x of the temperature control device on the upstream side from the position where the k-th control point of the rolled material 1 exists k,j (k = n + 1 to N, j = 1 to m(k) - 1) is fixed to the value calculated by the following formula (14) and treated as a constant. Also, as the inequality constraint condition formula, instead of formulas (2) and (3), formula (2) and the following formula (15) are used. Then, the operation amount determination unit 843 is the operation ratio x of the temperature control device on the downstream side D2 from the position where the k-th control point of the rolled material 1 exists k,j The optimal solution x of opt,k,j By solving the following formula (16) using the optimal solution x, the valve opening degrees z of the temperature control devices 40, 51 to 56 for the k-th control point of the rolled material 1 k,j (k = n + 1 to N, j = m(k) to 7) are calculated and updated. Note that when all the k-th control points of the rolled material 1 have passed through the installation positions of all the temperature control devices 40, 51 to 56 (when it is on the downstream side D2 from all the temperature control devices 40, 51 to 56), m(k) cannot be obtained. In this case, the operation amount determination unit 843 does not update the valve opening degrees z of the temperature control devices 40, 51 to 56 for the k-th control point k,j (k = n + 1 to N, j = 1 to 7).

[0088] [Number]

[0089] In this way, the processing device 80 measures the measured value θ of the temperature on the outlet side of the finishing rolling mill F,nFor each control point located on the trailing end side of the rolled material 1 with respect to the obtained control points, identify the temperature control device downstream of the position where the control point is located, and update only the operation amount of the temperature control device downstream of the position where the control point is located, so that it is possible to update only the operation amount of the temperature control device that affects the temperature on the exit side of the finishing rolling mill at the control point. Therefore, it is possible to improve the performance of the feedback control of the temperature on the exit side of the finishing rolling mill (for example, shortening the time until the temperature on the exit side of the finishing rolling mill reaches a steady state, and / or the temperature on the exit side of the finishing rolling mill approaching the target value, etc.).

[0090] In the present embodiment, the FB control unit 840 (temperature calculation unit 841) uses the initial value T of the calculated value of the temperature on the exit side of the finishing rolling mill calculated by the FF control unit 830 in order to reduce the calculation load (0) cal,n and the initial value z of the operation amount of each temperature control device (0) n,j and the maximum temperature changeable amount ΔT n,j (j = 1 to 7) to illustrate the case of calculating the calculated value T of the temperature on the exit side of the finishing rolling mill. However, the FB control unit 840 (temperature calculation unit 841) may obtain the temperature θ on the exit side of the rough rolling mill at the nth control point of the rolled material 1 cal,n and calculate the calculated value T of the temperature on the exit side of the finishing rolling mill at the nth control point of the rolled material 1 R,n cal,n and calculate the calculated value T of the temperature on the exit side of the finishing rolling mill at the nth control point of the rolled material 1

[0091] <Example> Next, examples will be described. Hereinafter, the examples and comparative examples of the present invention will be specifically shown and described in more detail, but the present invention is not limited to the following examples. ​In this embodiment, the results of computer simulation by the method described in this embodiment will be described. In both the inventive example and the comparative example, the lower limit temperature d of the temperature on the outlet side of the finishing rolling mill was set to 860°C, and the upper limit temperature u was set to 900°C. Also, the sampling pitch of the temperature on the outlet side of the roughing mill for the rough bar was set to 0.5 m, and the temperature on the outlet side of the roughing mill at each sampled control point was taken as the temperature on the outlet side of the roughing mill shown in FIG. 6. The distance from the tip of the rough bar on the horizontal axis of FIG. 6 represents the distance from the tip of the rolled material 1 in the state of the rough bar to each control point. Also, in order to show the difference due to the presence or absence of feedback control, the measured value θ of the temperature on the outlet side of the roughing mill at each control point R,k was set to be 10°C higher than the temperature calculated by computer simulation.

[0092] FIGS. 7, 8, and 9 show the simulation conditions and results of Comparative Example 1, Comparative Example 2, and the inventive example, respectively. The finishing rolling speed on the vertical axis in (a) of FIGS. 7 to 9 represents the rolling speed of the finishing tandem rolling mill 20 (the peripheral speed of the rolling rolls of the rolling stand F7) when each control point passes through the rolling stand F7. As shown in (a) of FIGS. 7 to 9, the finishing rolling speed was set to a pattern that accelerates from the middle of rolling and becomes constant. The valve openings in (c) to (i) of FIGS. 7 to 9 are represented by relative values with 1 when fully open and 0 (zero) when fully closed. Also, the F1 outlet side spray device, F2 outlet side spray device, F3 outlet side spray device, F4 outlet side spray device, F5 outlet side spray device, and F6 outlet side spray device on the vertical axis in (d), (e), (f), (g), (h), and (i) of FIGS. 7 to 9 represent the cooling spray devices 51, 52, 53, 54, 55, and 56, respectively.

[0093] In Comparative Example 1, which is an example of the conventional method, as described in Patent Document 2, the feedforward operation amount of the temperature control device at each control point is obtained based on the measured value of the temperature on the outlet side of the rough rolling mill at each control point. Then, after the temperature on the outlet side of the finishing rolling mill is measured, the temperature deviation between the measured value and the target value of the temperature on the outlet side of the finishing rolling mill is integrated, and the feedback operation amount of the temperature control device is obtained so as to take precedence over the temperature control device located downstream. The sum of the feedforward operation amount and the feedback operation amount is used as the operation amount of the temperature control device. The results of the computer simulation of Comparative Example 1 are shown in FIGS. 7(b) to 7(i).

[0094] In Comparative Example 2, which is another example of the conventional method, as described in Patent Document 3, until the temperature on the outlet side of the finishing rolling mill is measured, the initial operation amount of the temperature control device is obtained as the feedforward operation amount so as to preferentially use it based on the measured value of the temperature on the outlet side of the rough rolling mill from the temperature control device located upstream. Then, when the temperature on the outlet side of the finishing rolling mill is measured, the feedforward operation amount is fixed at that value. After the temperature on the outlet side of the finishing rolling mill is measured, the temperature deviation between the measured value and the target value of the temperature on the outlet side of the finishing rolling mill is integrated, and the operation amount of the temperature control device located most downstream among the temperature control devices that output a non-zero operation amount is used as the feedback operation amount, and the operation amount of the temperature control device is corrected by adding it to the feedforward operation amount fixed as described above. The results of the computer simulation of Comparative Example 2 are shown in FIGS. 8(b) to 8(i).

[0095] In the inventive example, as described in this embodiment, the initial value of the operation amount of the temperature control device for each control point is determined as the feedforward operation amount based on the measured value of the temperature on the outlet side of the rough rolling mill at each control point. Then, after the temperature on the outlet side of the finishing rolling mill is measured, a correction amount for the temperature on the outlet side of the finishing rolling mill is calculated based on the measured value of the temperature on the outlet side of the finishing rolling mill and the calculated value of the temperature on the outlet side of the finishing rolling mill, and the operation amount of each temperature control device is replaced with the feedback operation amount based on the calculated correction amount for the temperature on the outlet side of the finishing rolling mill and the feedforward operation amount. The results of the computer simulation of the inventive example are shown in FIGS. 9(b) to 9(i). In FIGS. 7 to 9, the case where the operation amount of the temperature control device using the measured value of the temperature on the outlet side of the finishing rolling mill is not changed (that is, the addition of the feedback operation amount) is indicated by a dotted line, and the case where it is performed is indicated by a solid line. Also, the time on the horizontal axis is the time when the tip of the rolled material 1 reaches the installation position of the rough bar cooling device 40 is set to 0 (zero).

[0096] In Comparative Example 1, as shown in FIG. 7, after 36.7 s when the measured value of the temperature on the outlet side of the finishing rolling mill in (b) exceeded the upper limit temperature of 900°C, in the order of the F6 outlet spray device in (i), the F5 outlet spray device in (h), and the F4 outlet spray device in (g) (in the order of the cooling spray devices 56, 55, 54), by changing the valve opening degree in the opening direction, the measured value of the temperature on the outlet side of the finishing rolling mill in (b) was changed within the range of 860 to 900°C, which is the range of the upper and lower limit temperatures, at about 52.8 s. However, in this method, since the operation amount of the downstream cooling spray device is greatly corrected, there is a high possibility that the shape of the rolled material 1 deteriorates. Also, although the tip of the rolled material 1 reaches the installation position of the temperature gauge 70 on the outlet side of the finishing rolling mill and the measurement of the temperature on the outlet side of the finishing rolling mill starts at 22.3 s, there is a problem that the operation amount (valve opening degree) of the rough bar cooling device 40 and the operation amounts of the cooling spray devices 51 to 56 (valve opening degrees of the F1 to F6 outlet spray devices) are not changed until 36.7 s when the measured value of the temperature on the outlet side of the finishing rolling mill exceeds the upper limit temperature of 900°C.

[0097] In Comparative Example 2, as shown in Fig. 8, after 36.7 s (point A) when the measured value of the temperature on the outlet side of the finishing rolling mill in (b) exceeded the upper limit temperature of 900°C, the rough bar cooling device in (c), the spray device on the F1 outlet side in (d), the spray device on the F2 outlet side in (e), the spray device on the F3 outlet side in (f), the spray device on the F4 outlet side in (g), and the spray device on the F5 outlet side in (h) were adjusted in the order of the rough bar cooling device 40, the cooling spray devices 51, 52, 53, 54, 55 (in the order of the spray devices on the F1 to F5 outlet sides) by changing the valve opening degree in the opening direction. As a result, the measured value of the temperature on the outlet side of the finishing rolling mill in (b) was corrected to the range of 860 to 900°C, which is the upper and lower limit temperatures, at about 59.9 s. However, in this method, the waste time from operating the upstream cooling control device, which is the object of the operation amount change at the initial stage of the feedback control, until the result appears in the measured value of the temperature on the outlet side of the finishing rolling mill is very long. Specifically, the control point (refer to point A) where the temperature control is first executed at the time of 36.7 s (point A) when the measured value of the temperature on the outlet side of the finishing rolling mill in (b) exceeded the upper limit temperature of 900°C takes 15.3 s to move to the installation position of the temperature gauge 70 on the outlet side of the finishing rolling mill and appear as the measured value of the temperature on the outlet side of the finishing rolling mill in (b) (refer to point B) (this 15.3 s period is the period from point A to point B). Therefore, not only is the time required for the measured value of the temperature on the outlet side of the finishing rolling mill in (b) to reach the range of 860 to 900°C, which is the upper and lower limit temperatures, slower than that in Comparative Example 1, but also a large temperature drop occurs thereafter. Also, similar to Comparative Example 1, there is a problem that the operation amount (valve opening degree) of the rough bar cooling device 40 and the operation amounts (valve opening degrees of the spray devices on the F1 to F6 outlet sides in (d) to (i) of Fig. 8) of the cooling spray devices 51 to 56 are not changed until 36.7 s when the measured value of the temperature on the outlet side of the finishing rolling mill exceeds the upper limit temperature of 900°C.

[0098] In the inventive examples as compared with Comparative Examples 1 and 2, as shown in Fig. 9, after 22.3 s from the start of measurement of the temperature on the outlet side of the finishing rolling mill, the valve opening degree is preferentially changed in the opening direction from the temperature control device located upstream with respect to each control point. Therefore, the measured value of the temperature on the outlet side of the finishing rolling mill in Fig. 9(b) is within the range of the upper and lower limit temperatures of 860 to 900 °C over the entire length of the rolled material 1. In Comparative Example 2, in order to more clearly show the difference from the inventive example, a case where the feedforward operation amount is fixed is exemplified, which is different from Comparative Example 1 and the inventive example. However, the lengthening of the idle time in Comparative Example 2 does not depend on the form of the feedforward control.

[0099] As described above, in the inventive example, by preferentially correcting the operation amount from the temperature control device located upstream, it is possible to suppress the deterioration of the shape of the rolled material. Further, feedback control can be executed without being affected by the idle time. Also, when the temperature on the outlet side of the finishing rolling mill is within the range of the upper and lower limit temperatures, even if the measured value of the temperature on the outlet side of the finishing rolling mill is within the lower limit temperature or higher and the upper limit temperature or lower, the correction amount of the temperature on the outlet side of the finishing rolling mill is calculated and the operation amount of the temperature control device is redetermined, so that high responsiveness of temperature control can be achieved.

[0100] Note that the embodiments of the present invention described above can be realized by a computer executing a program. Also, a computer-readable recording medium recording the program and a computer program product such as the program can also be applied as embodiments of the present invention. As the recording medium, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, etc. can be used. In addition, the embodiments of the present invention described above are merely examples of the concretization in implementing the present invention, and the technical scope of the present invention should not be construed in a limited manner by these. That is, the present invention can be implemented in various forms without departing from its technical idea or its main features.

Explanation of Reference Numerals

[0101] 1 Rolled material 10 Rough rolling mill 20 Finishing tandem rolling mill 30 Tracking device 40 Rough bar cooling device 51 - 56 Cooling spray device 60 Thermometer on the outlet side of the rough rolling mill 70 Thermometer on the outlet side of the finishing rolling mill 80 Processing device 100 Rolling equipment 810 Temperature acquisition part on the outlet side of the finishing rolling mill 820 Temperature acquisition part on the outlet side of the rough rolling mill 830 FF control part 831 Initial value calculation part 832 Output part 840 FB control part 841 Temperature calculation part 842 Correction amount calculation part 843 Manipulation amount determination part 844 Output part D1 Upstream side D2 Downstream side F1 - F7 Rolling stands R Conveyor path

Claims

1. A processing device that determines an operation amount of a temperature adjustment device for adjusting the temperature of a rolled material during conveyance from the outlet side of a rough rolling mill to the outlet side of a finish rolling mill, a finish rolling mill outlet temperature acquisition means for acquiring a measured value of the finish rolling mill outlet temperature, which is the temperature of the rolled material at the outlet side of the finish rolling mill, a temperature calculation means for calculating a calculated value of the finish rolling mill outlet temperature based on the latest value of the operation amount of the temperature adjustment device, a correction amount calculation means for calculating a correction amount of the finish rolling mill outlet temperature based on the measured value of the finish rolling mill outlet temperature acquired by the finish rolling mill outlet temperature acquisition means and the calculated value of the finish rolling mill outlet temperature calculated by the temperature calculation means, an operation amount determination means for determining the operation amount of the temperature adjustment device for the rolled material for which the measured value of the finish rolling mill outlet temperature was acquired based on the correction amount of the finish rolling mill outlet temperature, comprising: a plurality of control points are set for the rolled material at intervals in the conveyance direction of the rolled material, when a measured value of the finish rolling mill outlet temperature at one of the control points is acquired, the temperature calculation means calculates a calculated value of the finish rolling mill outlet temperature at the control point, the correction amount calculation means calculates a correction amount of the finish rolling mill outlet temperature at the control point based on the measured value of the finish rolling mill outlet temperature at the control point and the calculated value of the finish rolling mill outlet temperature at the control point, the operation amount determination means determines the operation amount of the temperature adjustment device for all the control points located on the rear end side of the control point existing at the measurement position of the finish rolling mill outlet temperature based on the correction amount of the finish rolling mill outlet temperature at the control point, The operation amount determination means identifies a temperature adjustment device located downstream of the position where the control point exists for all the control points located on the rear end side of the control point existing at the measurement position of the finish rolling mill outlet temperature, and updates only the operation amount of the temperature adjustment device located downstream of the position where the control point exists. A processing device.

2. a rough rolling mill outlet temperature acquisition means for acquiring a measured value of the rough rolling mill outlet temperature, which is the temperature of the rolled material at the outlet side of the rough rolling mill, further comprising: the temperature calculation means calculates a calculated value of the finish rolling mill outlet temperature at the position of the rolled material where the measured value of the rough rolling mill outlet temperature is acquired by the rough rolling mill outlet temperature acquisition means based on the latest value of the operation amount of the temperature adjustment device, The processing device according to claim 1, wherein the operation amount determination means determines the operation amount of the temperature control device so that the finish rolling machine outlet side temperature corrected by the correction amount of the finish rolling machine outlet side temperature satisfies a predetermined temperature condition.

3. Initial value calculation means for calculating an initial value of the operation amount of the temperature control device for the control point and an initial value of the calculated value of the finish rolling machine outlet side temperature at the control point achieved by the operation of the initial value based on the measured value of the rough rolling machine outlet side temperature which is the temperature of the rolled material on the outlet side of the rough rolling machine. further comprising The temperature calculation means calculates the calculated value of the finish rolling machine outlet side temperature at the control point by using the initial value of the calculated value of the finish rolling machine outlet side temperature at the control point, the initial value of the operation amount of the temperature control device for the control point, and the latest value of the operation amount of the temperature control device for the control point when the measured value of the finish rolling machine outlet side temperature at the control point is obtained. The processing device according to claim 1 or 2.

4. The operation amount determination means determines the operation amount of the temperature control device so that the finish rolling machine outlet side temperature corrected by the correction amount of the finish rolling machine outlet side temperature is equal to or higher than a preset lower limit temperature and equal to or lower than an upper limit temperature. The processing device according to any one of claims 1 to 3.

5. A processing method for determining the operation amount of a temperature control device for adjusting the temperature of a rolled material during conveyance from the outlet side of a rough rolling machine to the outlet side of a finish rolling machine, a finish rolling machine outlet side temperature acquisition step of acquiring a measured value of the finish rolling machine outlet side temperature which is the temperature of the rolled material on the outlet side of the finish rolling machine; a temperature calculation step of calculating a calculated value of the finish rolling machine outlet side temperature based on the latest value of the operation amount of the temperature control device; a correction amount calculation step of calculating a correction amount of the finish rolling machine outlet side temperature based on the measured value of the finish rolling machine outlet side temperature acquired in the finish rolling machine outlet side temperature acquisition step and the calculated value of the finish rolling machine outlet side temperature calculated in the temperature calculation step; an operation amount determination step of determining the operation amount of the temperature control device for the rolled material for which the measured value of the finish rolling machine outlet side temperature is acquired based on the correction amount of the finish rolling machine outlet side temperature; comprising a plurality of control points are set for the rolled material at intervals in the conveyance direction of the rolled material. In the temperature calculation step, when a measured value of the temperature on the outlet side of the finishing rolling mill at one of the control points is acquired, a calculated value of the temperature on the outlet side of the finishing rolling mill at the control point is calculated. In the correction amount calculation step, based on the measured value of the temperature on the outlet side of the finishing rolling mill at the control point and the calculated value of the temperature on the outlet side of the finishing rolling mill at the control point, a correction amount of the temperature on the outlet side of the finishing rolling mill at the control point is calculated. In the operation amount determination step, based on the correction amount of the temperature on the outlet side of the finishing rolling mill at the control point, the operation amount of the temperature control device for all the control points located on the rear end side of the control point existing at the measurement position of the temperature on the outlet side of the finishing rolling mill is determined. In the operation amount determination step, for all the control points located on the rear end side of the control point existing at the measurement position of the temperature on the outlet side of the finishing rolling mill, a temperature control device located downstream of the position where the control point exists is specified, and only the operation amount of the temperature control device located downstream of the position where the control point exists is updated.

6. A program for causing each means to function as the processing device according to any one of Claims 1 to 4.

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