JP3450108B2 - Hot rolled sheet cooling control device - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cooling control apparatus of hot rolled plate which definitive the cooling line for cooling the sheet material, such as a hot-rolled steel sheet.

[0002]

2. Description of the Related Art Conventionally, control of a coiling temperature of a steel sheet between a finishing step and a coiling step in a hot rolling facility is important in determining a material and is proposed in Japanese Patent Publication No. 62-22687. In addition, the transfer time is calculated from the transfer speed of the steel plate, and the steel plate temperature after the temperature drop due to the radiation of the steel plate is calculated from the transfer time and the steel plate temperature detected by the temperature detector. Calculate the cooling time using the winding temperature determined from, the steel plate thickness detected by the plate thickness detector, and calculate the cooling time and the residual cooling time associated with the transfer for each predetermined distance, The cooling device is on / off controlled until the calculated remaining cooling time becomes zero.

FIG. 17 is a diagram showing the structure of the above technique. In the figure, 1 is a rolling mill, 2 is a plate thickness gauge, 3 is a thermometer (exit side of finish rolling mill), 4 is a cooling device, 5 is a steel plate, 6 is a thermometer (winding), 7 is a winder, 8 is a speed detector, 11 is A / D
Converter, 12 is a first arithmetic unit, 13 is a shift memory, 1
Reference numeral 4 is a second arithmetic device, 15 is a valve opening / closing device, 16 is a timing generator, 17 is a predetermined length setter, and 18 is an adaptive corrector.

Next, the operation will be described. Speed detector 8
Detects the roll rotation speed of the rolling mill 1 and outputs it as a steel plate transfer speed. The A / D converter 11 converts each analog output signal of the plate thickness gauge 2, the thermometer 3 and the speed detector 8 into a digital signal and outputs the digital signal to the first arithmetic unit 12. The first arithmetic unit 12 calculates the required cooling time, and the shift memory 13
Output to. The shift memory 13 has a memory number corresponding to the number of spray banks of the cooling device 4 (generally, the cooling device 4 is composed of ten or more spray banks), and each memory stores the remaining cooling time under the spray bank. There is.

The second arithmetic unit 14 subtracts the residual cooling time stored in the i-th memory of the shift memory 13 by the elapsed time and stores the residual in the i + 1-th memory as the residual cooling time in the subsequent spray bank. . When the remaining cooling time is not 0, an output signal for opening the corresponding spray bank is output. The valve opening / closing device 15 opens / closes the spray bank according to an output signal from the second arithmetic device 14. The timing generator 16 integrates the output signal of the speed detector 8 and gives a start timing to the first and second arithmetic units 12 and 14 for every fixed length. Set the height. The adaptive corrector 18 adaptively corrects the heat transfer coefficient in the first and second arithmetic devices by using the actual temperature according to the output signal of the thermometer 6.

[0006]

As described above, in the prior art, it is difficult to control the output temperature of the finish rolling mill to the target coiling temperature by the cooling device by performing the predetermined temperature drop for the following reason. However, it has a drawback that it cannot be said to be a control method having sufficient accuracy.

Since the time for which the steel sheet is transferred between the exit side thermometer and the coiling thermometer of the finishing rolling mill is calculated only at the rolling speed and the acceleration rate at the start of cooling, the finishing is generally performed in the hot rolling equipment. The speed variation due to the temperature control on the exit side of the finishing rolling mill, which is carried out in the process, is not taken into consideration, and the control points of the steel sheet from the thermometer on the exit side of the finishing rolling mill to the coiling thermometer The control after the start of cooling is performed ignoring the change in the transfer time without knowing that the acceleration rate is changing by the time the control target point) is transferred. As a result, the desired winding temperature is not cooled and good control cannot be expected.

Further, since the cooling control system based on the time management is adopted, the time error is integrated, and similarly, the desired temperature of the steel sheet cannot be cooled.

The present invention has been made in order to solve the above problems, and improves the control accuracy over the entire length of the steel sheet from the tip to the tail end of the steel sheet for cooling, An object of the present invention is to provide a cooling control device capable of producing steel sheets of various qualities.

[0010]

Means for Solving the Problems (1) Heat according to the present invention
Cooling control device for rolled sheet material has a plurality of control points
The hot-rolled sheet material is placed in a cooling system composed of multiple banks.
Start cooling in the hot-rolled sheet cooling control device
Finished after each control point of the plate just before passes
Cooling control based on rolling mill outlet temperature, strip speed and strip thickness
First means for deriving a pattern and this cooling control pattern
After the start of cooling due to
Rolling mill exit side of the above plate material when passing through a fixed bank position
A cooling control pattern based on temperature, plate speed and plate thickness
Second re-deriving means, the re-deriving cooling
Use the control pattern to switch the banks after the above specified bank
It is designed to be cooled again.

(2) In the above (1),
The length is the same as the control points provided at equal intervals in the longitudinal direction of the plate material.
And the control point is in a predetermined bank position.
The cooling control pattern is re-derived every time it passes through
It was done so.

(3) In the above (1) or (2),
The second means is a predetermined method before reaching the outlet side of the cooling equipment.
Of already cooled sheet material when passing through the bank position of
Obtain the actual cooling amount and temperature from the actual cooling control pattern,
Using this, the specified van before reaching the outlet side of the cooling equipment
The cooling control pattern of the
It

(4) In any of the above contracts (1) to (3)
In deriving the cooling control pattern, the temperature drop due to water cooling with the laminar spray in the cooling equipment
Amount: Temperature drop due to water cooling by side spray in ΔTL cooling equipment
: ΔTs Temperature by water cooling with vertical spray in cooling equipment
Amount of drop: ΔTv Actual winding temperature: C
Temperature of cooling equipment by TA air cooling only: C
If Ti , the i-th control point is the actual winding temperature CTA
The required cooling temperature amount ΔTi at the time of is calculated by ΔTi = CTi-CTA ----- , while the cooling amount for each bank is totaled up to N banks.
The cooling amount ΔT

[Equation 1] And obtain the maximum ΔT in the equation under the condition ΔTi ≧ ΔT.
The maximum value of N is calculated and this N is used as the number of cooling banks for cooling.
Derive the control pattern and re-create the cooling control pattern.
The derivation is based on the total number of banks of the cooling equipment : NB The predetermined bank before reaching the outlet side of the cooling equipment: NF , the range of NF is NB> NF ≧ 2 , and the i-th control point is the actual winding temperature. Become a CTA
ΔTi = CTi-CTA-ΔTx --- The required cooling temperature amount ΔTi is calculated.
When it reaches (from 1 bank to NF bank)
Of the actual cooling amount obtained from the rejection control pattern,

[Equation 2] Under the condition of ΔTi ≧ ΔT ′, N that maximizes ΔT ′ in the equation
The maximum value of is calculated, and this N is used as the number of cooling banks for cooling control.
The pattern is re-derived.

(5) In (1) above, a learning function is provided.
At the same time, divide the plate into a plurality of pieces in the longitudinal direction and
The learning function is for the rolling mill outlet temperature, strip speed, and
Learner to modify cooling control pattern based on thickness and plate thickness
Derive the number and use these learning factors to cool the next segment
The control pattern is modified.

(6) In (5) above, the learning coefficient is derived.
Output is the actual winding temperature: C
Temperature of cooling equipment by TA air cooling only: C
If Ti , the i-th control point is the actual winding temperature CTA
The amount of cooling temperature ΔTi when the temperature becomes equal to is obtained by ΔTi = CTi-CTA , and the actual cooling value when passing through all banks (NB)
Rejected temperature amount ΔTc

[Equation 3] And Ci = ΔTi / ΔTc CN = (1-α) · Ci + α · Co, where 1 ≧ α ≧ 0 Co: learning coefficient last used value This CN is derived as a learning coefficient.
It

[0016]

[0017]

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. First, the principle of control in the present invention will be described. The amount of temperature drop from the exit-side thermometer of the finishing rolling mill to the winding thermometer is calculated by the following mathematical formulas (1) to (5).・ Temperature drop due to air cooling

[0019]

[Equation 7]

[Temperature drop due to water cooling]

[0021]

[Equation 8]

The above formulas (1) to (5) are all known formulas.

Here, σ: Stefan Boltzmann coefficient ε: Width emissivity Cp: Specific heat γ: Specific gravity HF: Sheet thickness TIME: Transfer time from FDT to CT (from the finishing rolling mill outlet temperature sensor to the coiling temperature detector) Transfer time) FDT: Actual temperature at exit side of finishing rolling mill V: Plate speed K: Absolute temperature conversion value VSTATUS: Vertical spray ON / OFF status (ON: 1.0
OFF: 0.0) QX: Total heat flux of upper and lower banks QV: Vertical spray heat flux QS: Side spray heat flux LBNK: Distance between banks WVS: Vertical spray jet width LSD: Side spray jet width KX: Number of side sprays

[0024] It should be noted, TIME (V) is one in which a well-known equation of motion of the L = v0 · t + (1/2 ) · α · t 2 was solved for t. L: Distance between FDT and CT v0: Plate speed at FDT α: Acceleration of plate between FDT and CT

First, every time each control point of the steel sheet passes directly under the finish rolling mill outlet side thermometer, the actual finish rolling mill outlet side temperature, the actual strip thickness and the actual speed are sampled,
Based on these, the on / off pattern of each bank of the cooling equipment for the point is determined in the following manner. The length of each bank and the control length of the steel sheet (the length between control points) are usually matched, and the next time each point passes just under the exit side thermometer of the finishing mill and advances by this control length, For the control point, turn on / off each bank of the cooling equipment for the next point by the same processing as that point.
The off pattern is determined.

Actual rolling speed (sheet speed) at the i-th control point:
Vi The actual finish rolling mill outlet temperature at the i-th control point (cooling equipment outlet side): FDTi The actual strip thickness at the i-th control point:
hi actual result Taken temperature:
Let's call it CTA.

When the steel sheet is conveyed to the position of the winding thermometer without using any cooling equipment, it can be predicted that the air cooling of formulas (1) and (2) will bring the winding temperature to CTi.
Therefore, the i-th control point is set to the actual collection temperature CTA.
The amount of cooling temperature when it becomes is ΔTi = CTi-CTA (6). On the other hand, the cooling amount ΔT, which is the total cooling amount of each bank up to N banks, can be calculated by the equations (3), (4), and (5).
It is represented by the following formula (7).

[0028]

[Equation 9]

In this equation (7), N means the required number of banks. When N increases, ΔT increases, but when it exceeds ΔTi, it will be overcooled, so it should not exceed ΔTi. That is, it means the maximum number of banks N that maximizes ΔT under the condition that ΔTi ≧ ΔT.

For example, in the formula (6), CTi = 800 °
C and CTA = 500, ΔTi = CTi−CTA = 800−500 = 300 (°
C).

On the other hand, since the temperature drop ΔTv due to the vertical spray is always cooling operation without ON / OFF control, this cooling temperature is set to 10 ° C. and one bank of laminar spray and side spray (N = 1). If the temperature drop per hit, that is, (ΔTL i + ΔTs i) = 50 ° C.,

In 5 banks, ΔT = 50 × 5 + 10 = 2
In a 60 (° C) 6 bank, ΔT = 50 × 6 + 10 = 310 (° C). From the condition of ΔTi ≧ ΔT, N in the equation (7) is 5 banks and 300 ≧ 260, and N = 5 is the required number of banks.

When N is determined in this way, the on / off pattern of each bank of the cooling equipment for the i point is determined. Before this i point passes through any bank outlet side before reaching the outlet side of the cooling equipment, the following calculation is performed at least once, and the point normally passed directly below the finishing rolling mill outlet side thermometer. It is expected that the above control will improve the accuracy of the control that has been set and calculated only occasionally.

Next, the cooling means after the start of cooling will be described. Total number of banks of cooling equipment NB Defined as the bank before reaching the outlet side of the cooling equipment NF, the range of NF must satisfy the condition of NB> NF ≧ 2. The reason why the NF does not take 1 is that the first bank has a small error and does not require correction.

At the time of the second setting calculation for this i point, the above equations (6) and (7) are ΔTi = CTi-CTA-ΔTx (8)

[0036]

[Equation 10]

ΔTx is obtained by the equation (9), and this ΔTx
Is the actual cooling amount obtained by sampling the actual bank on / off pattern when the i point reaches the NF bank exit side. That is, it is the actual cooling amount cooled from one bank to the NF bank. Also, equation (10) is NF
Taking into account the temperature cooled down to the bank in equation (8), the NF
For the remaining banks from the +1 bank to the NB bank, the latest actual speed and actual cooling amount are used to recalculate the on / off pattern of the bank of the cooling equipment. Here, N is the maximum number of banks such that ΔT ′ is maximized under the condition that ΔTi ≧ ΔT ′. When N is determined in this way, ON / OFF of each bank of the cooling equipment with respect to i point The off pattern is determined.

As described above, since the on / off pattern of the bank of the cooling equipment is recalculated using the latest actual speed and actual cooling amount for the remaining bank, a highly accurate cooling control device is provided. It will be.

Embodiments of the present invention will be described in detail below with reference to the drawings. This embodiment is a configuration diagram of a cooling control device using a cooling facility 1A in a winding temperature control device of a hot rolling facility as shown in FIG.

In the figure, 1A is a cooling facility, 2A is a steel plate, 3A is a finish rolling mill, 5A is a speed detector, 6A is a thermometer, 7A is a plate thickness gauge, 8A is a temperature predicting device, and 9A is a cooling bank on / An OFF determination device, 10A is a cooling bank control device, and 11A is a cooling bank ON / OFF correction determination device.

Steel plate 2A rolled by finish rolling mill 3A
Is taken up by the winding machine 4A through the cooling equipment 1A.
A speed detector 5A, a thermometer 6A, and a plate thickness gauge 7A are installed on the inlet side and the outlet side of the cooling device 1A (the outlet side is not shown) , and the inlet and outlet sides of the steel plate 2A are cooled by the cooling equipment. The actual temperature and rolling speed on the side are detected by the thermometer 6A and the speed detector 5A, and the actual plate thickness is detected by the plate thickness gauge 7A, and the above-mentioned temperature calculation is performed using the actual temperature and rolling speed at each control point i of the plate. The cooling facility control pattern is determined by the equations (1) to (7).

The cooling equipment 1A is divided into ten or more cooling zones, and each cooling zone can be independently opened / closed to control the amount of water injection and to control the temperature of the steel sheet over the entire length.

When the control point i passes the NF bank outlet side, the detection result of the speed detector 5A for the point i is input to the steel plate temperature predicting device 8A by the above-mentioned equations (8) to (10). In the cooling bank on / off determination device 9A by the temperature prediction device 8A, the steel plate 2A is the speed detector 5
The speed is detected by A, ON / OFF of the cooling bank of the cooling equipment 1A is calculated, and recalculation and determination are made so as to reach the target winding temperature.

The on / off of the determined cooling bank is controlled by the cooling bank control device 10A so that the cooling bank is cooled when the control point of the steel sheet passes. Each time the control length passes, the control pattern at the control point is input to the cooling bank on / off correction determining device 11A by the same process as described above. . Cooling bank control device 10 according to the determined on / off pattern of the cooling bank
It is controlled by A so as to be cooled when the target steel plate portion passes.

Next, the operation will be described with reference to the flow charts of FIGS. (1) The "temperature, rolling speed, plate thickness" of the tip of the steel plate 2A on the cooling equipment entrance side is input to the temperature prediction device 8A. (S
1) (2) The temperature predicting device 8A calculates the air cooling amount CTi at the i-th control point by the equations (1) and (2), and the required cooling temperature amount Δ at the i-th control point is obtained from the equation (6).
Calculate Ti. (S2)

(3) The temperature predicting device 8A calculates the equations (3), (4) and (5) for each bank, and obtains the cooling temperature amount ΔT for each bank from the equation (7). (S3) (4) The cooling bank on / off determination device 9A determines the cooling bank on / off pattern using the water cooling drop amount ΔT and inputs it to the cooling bank control device 10A. (S4)

(5) Each time the control point of the steel sheet 2A passes through the cooling equipment entrance side (finishing mill exit side), the cooling bank controller 10A controls the cooling equipment 1A to cool the steel sheet 2A. (S5) (6) It is determined whether or not the steel plate 2A has turned off the winding thermometer. If YES, the process ends, and if NO, the process proceeds to S7.
(S6)

(7) The control point i is a predetermined bank (N
It is determined whether or not F) has been passed, and if not, S5
Return. (S7) (8) From S5 to S7, the cooling operation of S5 is repeated until the control point passes the NF bank.
After passing the bank, go to S8. (S5 to S7) (9) The "temperature, rolling speed, plate thickness" of the steel plate 2A on the cooling device entrance side is input to the temperature prediction device 8A.

(10) The cooling bank on / off correction determining device 11A calculates the equations (8), (9) and (10) to obtain ΔT '.
Is derived, the cooling bank on / off pattern is corrected by this ΔT ′, and the corrected cooling bank on / off pattern is input to the cooling bank controller 10A. (S9) (11) Cooling bank on / corrected by recalculation in S9 /
According to the off pattern, cooling is executed in S5.

By correcting the cooling bank on / off pattern and cooling in this way, it is possible to obtain an accurate winding temperature. The predetermined bank (NF) in S7 is not limited to one, and a plurality of banks may be designated.

According to this embodiment, instead of the conventional control method using the cooling time, the cooling equipment control pattern is always determined for each control point from the tip to the tail end, and the result is obtained in the middle of the cooling equipment. At least 1 recalculation with values
Since a means for performing and controlling the operation more than once is adopted, it is possible to perform highly accurate cooling control capable of producing a steel sheet of sufficient quality.

Embodiment 2. This embodiment is shown in the block diagram of the cooling control device in FIG. In the drawings, the first embodiment
1 is different from that shown in FIG. 1 in that a control point detector 15A is provided, and the control point is detected by a signal from the speed detector 5A. In the first embodiment, the recalculation is performed in a predetermined bank (NF bank), but in the present embodiment, the recalculation is performed every time the control point i passes through each bank.

The above operation will be described with reference to the flow charts of FIGS. (1) T1 to T6 are the same as the first embodiment and S1 to S6 in FIG. (2) At T7, every time the control point i passes through one bank, the "temperature, rolling speed,
The "plate thickness" is input to the temperature prediction device 8A.

(3) At T8, the cooling bank on / off correction determining device 11A calculates equations (8), (9) and (10) to derive ΔT ', and at this ΔT' the cooling bank on / off is calculated. The off pattern is modified, and the modified cooling bank on / off pattern is input to the cooling bank controller 10A.

(4) According to the cooling bank on / off pattern recalculated and corrected at T8, cooling is performed at T5,
After that, the cycle is repeated from T5 to T8, and repeated until the steel plate 2A turns off the winding thermometer (not shown) at T6 (until the steel plate 2A passes through the cooling equipment).

In the first embodiment, the cooling facility control pattern is recalculated and determined based on the upstream actual value only when the steel sheet passes through the NF bank. However, in the second embodiment,
Each time the steel sheet passes the control length (control point), the on / off pattern of the bank of the cooling equipment is finely determined by recalculation. It is possible to provide good means and perform highly accurate cooling control capable of producing a steel sheet of good quality.

Third Embodiment This embodiment is shown in the block diagram of the cooling control device of FIG. In the drawings, the first embodiment
1 is different from FIG. 1 in that a learning control device 12A is provided, and a learning coefficient is obtained from the cooled actual value, and this learning number is used when cooling the next material.

In the temperature calculation of the above equations (1) to (10), all are performed by the feedforward, that is, the predictive control. Therefore, the accuracy may be insufficient depending on the prediction accuracy of each of the above temperature predicting equations. sell. Therefore, using this temperature formula, the actual winding temperature, speed, exit-side temperature speed of the finishing rolling mill, and the on / off pattern of the bank of the cooling equipment are used to calculate the actual temperature values by the following formulas (11) to (14). ), The learning control is applied to one steel plate to be cooled next in consideration of the difference between the predicted value and the actual value, and the accuracy is improved by adaptive control.

ΔTi = CTi−CTA (11) The formula (11) is the same as the formula (6), and CTi is the winding temperature CTA of only the air cooling of the formulas (1) and (2). Regarding the temperature ΔTi, the i-th control point is the actual measured temperature CTA.
It is the amount of cooling temperature when it becomes.

[0060]

[Equation 11]

ΔTc in the equation (12) is calculated for all banks (N
It is the actual cooling temperature amount when passing through B). Ci = ΔTi / ΔTc (13) CN = (1−α) · Ci + α · Co (14) where 1 ≧ α ≧ 0 Co: learning coefficient last used value

The equation (13) is for obtaining the ratio Ci between the predicted value and the actual value when the control point i reaches the exit side of all banks (NB), and CN of the equation (14) is The learning coefficient is a learning coefficient adjusted with α to determine how much weight the learned Ci is corrected for the next material. The CN obtained by the equation (14) is multiplied by the temperature calculation ΔT when determining the control pattern of the next material, and is obtained by the equation in which the prediction accuracy is improved.
This value of CN is adopted as being constant over the entire length of each steel sheet.

The above operation will be described with reference to the flowcharts of FIGS. (1) U1, U2, U4 to U6 are the same as in the first embodiment and S1, S2, S4 to S6 in the figure, but the difference from U3 in S3 is that the learning coefficient CN is If stored, ΔT multiplied by CN is Δ
Let T. (2) At U7, the "temperature, rolling speed, plate thickness" of the steel plate 2A on the cooling device entrance side is input to the temperature prediction device 8A.

(3) At U8, the cooling bank on / off correction determining device 11A calculates equations (8), (9) and (10) to derive ΔT ', and at this ΔT', the cooling bank on / off is calculated. The off pattern is modified, and the modified cooling bank on / off pattern is input to the cooling bank controller 10A.

(4) U9, steel plate 2A on the inlet side of the cooling equipment
"Temperature / rolling speed / sheet thickness" is input to the learning control device 12A. (5) In U10, in the learning control device 12A, the expression (1
1) to (14) are calculated, and the learning coefficient CN is obtained and stored. In step U3, this CN is multiplied by the temperature calculation value for cooling the next material.

As described above, in the third embodiment, the temperature formula used for the calculation is corrected by using the actual value to improve the prediction accuracy, and then the steel plate is finely tuned from the tip to the tail. It is possible to provide more precise control means and perform highly precise cooling control capable of producing a steel sheet of good quality.

Fourth Embodiment This embodiment is shown in the block diagram of the cooling control device in FIG. In the figure, the difference from FIG. 7 of the third embodiment is that a learning thermometer 14A that is input to the learning control device 12A is provided, and the temperature of the steel sheet 2A that is scraped off (or the output of the cooling equipment 1A). Side temperature).

In the fourth embodiment, a steel plate is divided into at least two parts in the longitudinal direction to obtain a learning coefficient for each section, and the learning coefficient corresponding to each section of the steel sheet is used when cooling the next material. is there.

C obtained by the equation (14) of the third embodiment
Although N is multiplied by the temperature calculation when determining the control pattern of the next material to improve the prediction accuracy, in this embodiment, the steel plate is divided into at least two parts in the longitudinal direction and the learning coefficient is calculated for each section. The coefficient corresponding to each section of the steel plate is obtained and adopted by (14). The method of division may be, for example, a distance of several meters from the tip and beyond, or may be divided into three to divide into tip / center / tail end. In general, when cooling a steel sheet, the amount of cooling at the tip end and the amount of cooling at the tail end often differ from the amount of cooling at the center. Therefore, the learning coefficient CN is obtained by dividing into the tip portion / center portion / tail end portion and applied to the next material.

The above operation will be described with reference to the flow charts of FIGS. This flowchart is obtained by adding step V9 to the flowchart of the third embodiment.

(1) In V9, when a predetermined portion of the steel plate 2A (divided into two at least one portion at the tip portion / central portion / tail end portion, etc.) comes to the cooling equipment entrance side, (2) cooling at V10 "Temperature / rolling speed / sheet thickness" of the steel sheet 2A on the equipment entry side is input to the learning control device 12A, and (3) the learning control device 12A calculates the equations (11) to (14) to obtain the learning coefficient CN. Seek and memorize. This CN is multiplied by the calculated temperature value at the time of cooling the next material. In this way, the cooling amount in the longitudinal direction of the rolled material can be controlled using the learning function.

In the third embodiment, the temperature formula used for the calculation is corrected by using the actual values, and the learning accuracy of one point per steel sheet is used to improve the prediction accuracy. The behavior is not always constant over the course of the temperature cooling process. In the fourth embodiment, at least two learning coefficients are calculated from the tip to the tail and are applied to each point of the steel sheet, so that finer and more precise control can be performed, and therefore, good High-precision cooling control that can produce high-quality steel plates can be performed.

Embodiment 5. This embodiment is shown in the block diagram of the cooling control device of FIG. The configuration of FIG. 13 is the same as that of FIG. 10 of the fourth embodiment. In the fourth embodiment, the steel plate is divided into at least two parts in the longitudinal direction, the learning coefficient CN is obtained for each section by the equation (14), and the obtained learning coefficient CN is applied when the next material is cooled. In the form 5, the learning coefficient CN obtained during cooling is also applied to the uncooled portion of the steel plate 2A during cooling.

In the fifth embodiment, similarly to the fourth embodiment, CN obtained by the equation (14) is multiplied by the temperature calculation when determining the control pattern of the next material, and the prediction accuracy is improved by the equation. Ask. This value is obtained by dividing the steel plate into at least two parts in the longitudinal direction to obtain the learning coefficient for each section by the formula (14), and obtaining and adopting the coefficient corresponding to each section of the steel sheet.

The method of division may be, for example, a distance of several meters from the tip and thereafter, or may be divided into three to divide into tip / center / tail.

Further, in the feed forward control, BA
Even if the adaptive control by learning R T0 BAR (the result of learning with one plate is reflected in the next plate) is introduced, it is not always possible to secure sufficient accuracy from the front end to the tail end of the steel plate. Therefore, when trying to obtain the learning coefficient by dividing the steel plate into at least two parts, every time the control point passes through at least one control length (distance between the control points) after the control of the tip part ends except for the tip part. , Dynamically learning the controlled point (cooled portion) with respect to the control point of the upstream (uncooled portion) steel sheet whose control is not yet finished by dynamically using the equation (14). By reflecting the coefficient, the control accuracy of the central portion of the steel sheet is improved.

The tip portion is excluded here because it is often excluded from the calculation because the tip portion has a different cooling effect from other portions. However, when the cooling effect of the tip portion is not so different from that of the other portions, the tip portion may be used for the calculation.

The above operation will be described with reference to the flow charts of FIGS. This flowchart is the same as the fourth embodiment and the flowchart of FIG. 12 and step W11 of FIG. 15 in place of step V11, and is otherwise the same.

(1) In W9, if a predetermined portion of the steel plate 2A (divided into two at least one portion at the tip portion / center portion / tail end portion) comes to the cooling equipment entrance side, (2) cooling at W10 Input the "temperature, rolling speed, plate thickness" of the steel plate 2A at the equipment entry side into the learning control device 12A,

(3) In the learning control device 12A, the equations (11) to (14) are calculated, and the learning coefficient CN is calculated and stored. The obtained CN is multiplied by the calculated temperature value of the uncooled steel plate 2A during cooling. Also, the obtained CN is multiplied by the temperature calculated value at the time of cooling the next material. In this way, the cooling amount in the longitudinal direction of the rolled material can be controlled for both the uncooled portion of the member being cooled and the next material by using the learning function.

In the fifth embodiment, since the learning coefficient is reflected in the second half of the steel sheet by using the result of the first half of the steel sheet, the steel sheet of higher quality than the fourth embodiment can be produced. Accurate cooling control can be performed.

Sixth Embodiment This embodiment is shown in the block diagram of the cooling control device in FIG. In the figure, the difference from FIG. 13 of the fifth embodiment is that the feedback control device 1
3A is provided.

High-precision control is possible to some extent by using the predictive control shown in the first to fifth embodiments. However, if the precision is not sufficient by this control, the feedback control device 13A is used.
By introducing, the accuracy of the actual cooling temperature with respect to the target cooling temperature is further improved.

[0084] feedback controller 13A in response to the difference between the target卷取<br/> temperature and actual coiling temperature CTA, to cooling bank controllers 10A, commands to adjust the amount of cooling,
The cooling amount is adjusted by the cooling bank controller 10A. Normally, the cooling equipment 1A has a dozen or more banks, but the final bank is a bank that is not subject to on / off control (called a vernier bank), and the feedback control described above is used to finely adjust the cooling amount in this bank. By.

As described above, in the sixth embodiment, since the feedback control is introduced so as to absorb the poor feedforward accuracy, the cooling control can be performed with high accuracy.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a cooling control device for hot-rolled sheet material according to Embodiment 1 of the present invention.

FIG. 2 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the first embodiment of the present invention.

FIG. 3 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram of a cooling control device for hot-rolled sheet material according to Embodiment 2 of the present invention.

FIG. 5 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the second embodiment of the present invention.

FIG. 6 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the second embodiment of the present invention.

FIG. 7 is a configuration diagram of a cooling control device for hot-rolled sheet material according to Embodiment 3 of the present invention.

FIG. 8 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the third embodiment of the present invention.

FIG. 9 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the third embodiment of the present invention.

FIG. 10 is a configuration diagram of a cooling control device for hot-rolled sheet material according to Embodiment 4 of the present invention.

FIG. 11 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the fourth embodiment of the present invention.

FIG. 12 is a flowchart of the operation of the hot-rolled sheet material cooling control device according to the fourth embodiment of the present invention.

FIG. 13 is a configuration diagram of a cooling control device for hot-rolled sheet material according to Embodiment 5 of the present invention.

FIG. 14 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the fifth embodiment of the present invention.

FIG. 15 is a flowchart of the operation of the hot-rolled sheet material cooling control apparatus according to the fifth embodiment of the present invention.

FIG. 16 is a configuration diagram of a cooling control device for hot-rolled sheet material according to Embodiment 6 of the present invention.

FIG. 17 is a configuration diagram of a conventional cooling control device for a hot rolled sheet material.

[Explanation of symbols]

1A cooling equipment, 2A steel plate, 3A finishing rolling mill, 5
A Speed detector, 6A Thermometer, 7A Plate thickness gauge, 8A
Temperature prediction device, 9A cooling bank on / off determination device,
10A cooling bank control device, 11A cooling bank on / off correction determining device, 12A learning function computing device, 13
A feedback controller, 14A winding thermometer, 1
5A Control point detector.

Claims (6)

(57) [Claims] 1. A hot rolled sheet material having a plurality of control points
Is cooled by a cooling system composed of multiple banks.
In the cooling control device for hot rolled sheet material,
The finish rolling mill is released every time each control point of the plate material passes.
Cooling control pattern based on side temperature, plate speed and plate thickness
By the first means for deriving and the cooling control pattern
After the start of cooling, the specified van before reaching the outlet side of the above cooling equipment
Temperature of the above-mentioned plate when passing through the rolling mill
Re-derive cooling control pattern based on speed and plate thickness
And a second means for controlling the cooling control pattern.
Re-cools the banks above the specified bank
A cooling control device for hot-rolled sheet material. 2. A cooling control device for a hot-rolled sheet material according to claim 1.
In the table, the length of the bank is the longitudinal direction of the plate material.
The length between control points provided at
Each time the point passes a predetermined bank position, the cooling control
Hot rolled sheet material characterized by re-deriving turns to cool
Cooling control device. 3. A cooling control device for a hot-rolled sheet material according to claim 1.
In the above arrangement, the second means is provided on the outlet side of the cooling equipment.
Already cooled when passing through the prescribed bank position before reaching
From the actual cooling control pattern of the
Obtain the temperature and use it to reach the outlet side of the cooling equipment
To re-derive the cooling control pattern for a given bank of
A cooling control device for hot-rolled sheet material. 4. A hot rolled sheet according to claim 1.
In the material cooling control device, the above cooling control pattern is derived by the following: Temperature drop due to water cooling with laminar spray in cooling equipment: ΔTL Temperature drop due to water cooling with side spray in cooling equipment: ΔTs Vertical temperature in cooling equipment Temperature drop due to water cooling by spray: ΔTv Actual picking temperature: C
TA Outlet temperature only by air cooling: C
Assuming Ti, the required cooling temperature amount ΔTi when the i-th control point reaches the actual winding temperature CTA is obtained by ΔTi = CTi-CTA -----, while the cooling amount for each bank is N The total cooling amount ΔT to the bank is Then, the maximum value of N that maximizes ΔT in the equation is found under the condition of ΔTi ≧ ΔT, and the cooling control pattern is derived using this N as the number of cooling banks. Total number of banks: NB Predetermined bank before reaching the outlet side of the cooling equipment: NF, the range of NF is NB> NF ≧ 2, and the i-th control point becomes the actual winding temperature CTA. The required cooling temperature amount ΔTi is obtained by calculating ΔTi = CTi-CTA-ΔTx -----, and ΔTx in the formula is the actual cooling control when the i point reaches the NF bank exit side (1 bank to NF bank). The actual cooling amount obtained from the pattern is used to obtain the following formula: Under the condition of ΔTi ≧ ΔT ′, N that maximizes ΔT ′ in the equation
Is obtained and the cooling control pattern is re-derived by using this N as the number of cooling banks, and a cooling control apparatus for hot-rolled sheet material. 5. A cooling control device for hot-rolled sheet material according to claim 1.
In the installation, the learning function is provided and the plate material is divided into a plurality of pieces in the longitudinal direction, and the learning function corrects the cooling control pattern based on the rolling mill outlet side temperature, the sheet speed and the sheet thickness for each of the sections. A cooling control device for a hot-rolled sheet material, wherein a learning coefficient is derived and a cooling control pattern of the next section is modified using these learning coefficients. 6. A cooling control for a hot rolled sheet material according to claim 5.
In the device, the learning coefficient is derived by the actual winding temperature: C
TA Outlet temperature only by air cooling: C
Assuming Ti, the cooling temperature amount ΔTi when the i-th control point reaches the actual winding temperature CTA is obtained by ΔTi = CTi−CTA, and the actual cooling temperature amount ΔTc when passing through all banks (NB). Is given by Ci = ΔTi / ΔTc CN = (1−α) · Ci + α · Co, where 1 ≧ α ≧ 0 Co: learning coefficient last used value This CN is derived as a learning coefficient of the hot-rolled sheet material. Cooling control device.