JP3194447B2 - Rolled material cooling control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the cooling of a rolled material in hot rolling after finish rolling.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram of a conventional cooling device.
In FIG. 6, a rolled material 1 is rolled by a finish rolling mill 2 and then wound up by a winder 4 via a run-out table 3. During this time, the rolled material 1 is cooled by the plurality of cooling banks 5a and the fine adjustment cooling banks 5b. The finish rolling mill 2 is provided with a finish delivery speedometer 7, a thickness gauge 8, and a finish delivery thermometer 9. The detection signals of the finishing outlet speedometer 7, the thickness gauge 8 and the finishing outlet thermometer 9 are given to the cooling control device 6. The cooling bank 5a and the fine adjustment cooling bank 5b are each formed by arranging a plurality of water injection banks (not shown) over the transport path of the rolled material 1, and a cooling spray for injecting the rolled material 1 from above and below into each water injection bank. And the water injection operation is controlled for each water injection bank. The spray pattern and the water injection amount of the water injection bank to be used are respectively controlled based on the water injection command output from the cooling control device 6. A take-up thermometer 10 is provided on the output side of the run-out table 3, and a take-up speedometer 1 is provided on the take-up machine 4.
1 is installed. Each detection signal of the winding-side thermometer 10 and the winding-side speedometer 11 is given to the cooling control device 6.

Next, the operation will be described. Cooling control device 6, in order to maintain the required coiling temperature over the entire area of the strip 1 after hot rolling, to operate the cooling bank 5 a and the fine adjustment cooling bank 5b as follows. First, the speed, temperature, and thickness of the rolled material 1 after finish rolling are input from the finish output side speedometer 7, the thickness gauge 8, and the finish output side thermometer 9, respectively, and a required winding temperature is obtained from these input values. Calculate the amount of water needed to determine the spray pattern,
A water injection command is output to the cooling banks 5a and 5b. This calculation is performed for a fixed time or for a fixed distance. The moving speed of the rolled material 1 is such that the rear end of the rolled material 1 is
After being conveyed from the motor, it is detected by the take-up speedometer 11. Since it is difficult to achieve the required winding temperature over the entire area of the rolled material 1 only by the field forward control based on the above prediction, the winding-side thermometer 10
The feedback control in the bar is performed in which the actual value of the winding temperature is compared with the target winding temperature, and a water injection command is issued to the fine adjustment cooling bank 5b so as to correct the difference.

[0004]

However, even when the feedforward control and the feedback control are used together as described above, the temperature at the leading end of the rolled material is more likely to deviate from the target winding temperature than the intermediate temperature. There's a problem.
This includes a delay in response to the water injection command due to an accelerated change in the rolling speed of the leading end of the rolled material, a sudden change in heat transfer due to contact with the transport rollers of the run-out table,
Alternatively, various causes are conceivable, such as easy deviation from the required plate width. Therefore, corrections are made using the heat transfer coefficient, and adjustments such as changing the water injection amount or the target winding temperature only at the front end are performed. Since the correction is a fixed correction focusing only on the deviation, it has been difficult to stably and accurately control the cooling of the leading end of the rolled material.

The present invention has been made to solve the above problems, and has as its object to provide a method for controlling the cooling of a rolled material in which the leading end of the rolled material can be maintained at a required winding temperature. Things.

[0006]

Means for Solving the Problems] cooling control method according to a first aspect of the invention, the temperature model equation hot-finished rolled material
In the method of controlling cooling using
Of sheet speed at the tip of rolled material measured in rolling control
Based on measured values, roll speed of finishing mill and advance rate
Rate correction used for controlling the leading end of the next rolled material
Determine the coefficient, and measure the actual value of the plate speed and the initial pressure.
Based on the actual value of the transfer time of the leading end of the
Calculate the acceleration rate used to control the leading end of the rolled material.
Then, based on the above advanced rate correction coefficient,
Predict the plate speed of the part, and
At the next transport of the leading end of the rolled material based on the acceleration rate
It is characterized in that the interval is predicted. Claim 2
The cooling control method according to the present invention includes the steps of:
In the cooling control method using the temperature model formula,
Of rolled material measured in rolling control of rolled material
Sheet speed and roll speed of finishing mill
Control of the intermediate part of the current rolled material based on the rate of progress
Determine the advanced rate correction coefficient to be used and measure the above plate speed
Value and the actual value of the transport time of the leading end of the rolled material
Is used to control the intermediate part of the rolled material based on
Calculate the acceleration rate and, based on the above advanced rate correction coefficient,
Predict the plate speed after the middle part of this rolled material, and
Based on the predicted plate speed and the acceleration rate, the current pressure
The transfer time after the middle part of the rolled material is predicted.
And features.

[0007]

According to the first aspect of the present invention, the pressure of the first rolled material is
In rolling control, measure the sheet speed at the tip of the rolled material,
Based on the actual measured value of the strip speed, the tip of the next rolled material
The advanced rate correction coefficient used for the control of
Between the actual measured value of the
Used to control the leading end of the next rolled material based on the actual value
Calculate the acceleration rate. Then, based on the advanced rate correction coefficient,
To predict the plate speed at the tip of the next rolled material, and
Based on the predicted plate speed and the acceleration rate, the next pressure
Since the transfer time of the leading end of the rolled material is predicted, the next rolling
The accuracy of transport time prediction at the tip of material control has been improved,
The winding temperature of the leading end of the rolled material over a long period
Control accuracy is improved. In the invention of claim 2, this time
Speed at the tip of rolled material in rolling control of rolled material
The actual rolling speed
The advanced rate correction coefficient used for control after the middle part of the material
And the measured value of the above-mentioned strip speed and the
Based on the actual value of the transfer time of the end part,
The acceleration rate used for the control after the interval is obtained. And on
Based on the advanced rate correction coefficient,
The descending plate speed is predicted, and the predicted plate speed is
Conveying the rolled material from the middle part onward based on the acceleration rate
Since the time is predicted, the transfer time after the middle part of the rolled material
Prediction accuracy is improved, and winding is performed over the entire area of the rolled material.
Temperature control accuracy is improved.

[0008]

[Example] Example1.  FIG. 1 is a configuration diagram of a cooling device showing one embodiment of the present invention.
You. In FIG. 1, a rolled material 1 is a finishing mill (rolling section)
After being rolled in 2, it is wound up through run-out table 3
It is wound by a machine (winding unit 4). During this time, the rolled material 1 is cold.
A plurality of cooling banks 5a and a fine adjustment cooling bar
It is cooled by the link 5b. Finish rolling mill 2
Outlet speedometer 7, Finishing outlet thickness gauge 8, and Finishing outlet temperature
A meter 9 is provided. Also, run-out table 3
Winding on the exit side of~ sideA thermometer 10 is installed, and the winder 4
Is provided with a take-up speedometer 11. Speed correction performance
The calculating device 12 has a finishing output speedometer 7 and a winding speed.
Each detection signal of the total 11 is input, and the acceleration rate of the rolling material speed and the
And advance rate are calculated. This acceleration rate and advanced rate
Discharge side thickness gauge 8, finish discharge side thermometer 9, and winding side temperature
It is given to the temperature calculation device 13 together with each detection signal of the total 10.
You. Spray pattern and injection volume of the injection bank used
Is a cooling pattern based on the output result of the temperature calculation device 13.
It is determined by the determining device 14. Water injection determines the cooling pattern
Valve opening / closing based on water injection command output from device 14
This is performed by the device 15. Speed correction arithmetic unit 12, temperature
Each calculation of the degree calculation device 13 and the cooling pattern determination device 14
The equipment is based on rolled material specifications such as rolled material size and components.
With the concept of different, model using rolling conditions, actual values, etc.
Calculate Model calculations are performed at regular intervals.
Shall be

The following model equations are used for cooling control. The cooling capacity model formula is shown by formula (1).
You.

[0010]

(Equation 1)

[0011] The temperature model equation is shown by equation (2).

[0012]

(Equation 2)

The transport time model formula is shown by formula (3).

[0014]

(Equation 3)

The plate speed model formula is expressed by formula (4).

[0016]

(Equation 3)

[0017] Q: Cooling capacity α, β; constant  FT: Finishing mill exit side temperature K: Cooling capacity correction coefficientT1: Predicted winding temperature  ε; emissivity σ; Stefan-Boltzmann constant t; transport time c; specific heat ρ; specific gravity h;Tf: Atmospheric temperature  v0; initial plate speed a; acceleration rate L; transport distance vR; roll rotation speed f; advanced rate C; advanced rate correctionnumber

FIG . 2 is a block diagram showing a control state according to the first embodiment of the present invention. First, it is assumed that physical properties, model constants, initial values of variables, and the like necessary for calculation of the model formula are stored in advance in the arithmetic devices of the speed correction device 12, the temperature calculation device 13, and the cooling pattern determination device 14. . At this time, physical property values such as specific heat and specific gravity are stored as stratified data having different values depending on the size, components, and the like of the rolled material. When the leading end of the rolled material reaches the winding machine 4, the exit side speed and the winding speed of the finishing mill are given as input values to the speed correction calculating device 12, and the acceleration rate is calculated from the transport time model formula of the above formula (3). However, the advance rate is obtained from the plate speed model equation of the above equation (4). The obtained value is used as an initial value for the setup control of the rolled material to be cooled next. In the temperature calculating device 13, the plate speed and the transport time obtained by the speed correcting calculating device 12 , the target winding temperature, the finish-rolling mill exit side temperature, the finish-rolling mill exit side plate thickness, and the winding temperature are input. From the value, the temperature drop is calculated. The cooling pattern determination device 14 determines the water injection amount and the water injection pattern of each water injection bank so that the predicted winding temperature matches the target winding temperature.

The method of obtaining the advanced rate correction coefficient C is as follows. That is, the following equation (5) obtained by modifying equation (4) is used.
Can be calculated.

[0020]

(Equation 4)

[0021] In other words, the leading end of the rolled material during rolling control
Input to the speed correction arithmetic unit 12 when the
Of the plate speed (initial plate speed v0) at the tip of the rolled material
The measured value v0, the roll rotation speed vR of the finishing mill 2,
Based on the advance rate f determined by a known theoretical formula,
According to (5) above, it is used for controlling the leading end of the next rolled material.
The advanced rate correction coefficient C is found. That is, the advanced rate f
The accuracy is poor if you use only
By advanced rate (f · C) corrected by rate correction coefficient C
Formula (4) predicts the next strip speed at the leading end of the rolled material.
You. In other words, the rolled material measured during the first control of the rolled material
The advance rate is corrected by the measured value v0 of the plate speed at the tip of
To improve the accuracy of predicting the plate speed at the end of the next rolled material.
Let

The method of obtaining the acceleration rate a is as follows. That is , calculation is performed using the following equation (6) obtained by modifying the equation (3).
I can get out.

[0023]

(Equation 5)

[0024] In other words, of the distal end portion of the rolled material for the first time described above
The actual measured value v0 of the plate speed and the transport determined by the actual measured value v0
By the actual value t of the sending time, the leading end of the next rolled material is
An acceleration rate a used for control is obtained . In the rolling line, the rolled material becomes a product while being accelerated / decelerated, not at a constant speed. The acceleration rate indicates a speed change per unit time at this time.

[0025] Hereinafter, a specific description will be given. First rolled material
When the leading end reaches the winding machine 4, the winding speed,
The actual measured value v0 of the plate speed at the tip of the rolled material is corrected
It is input to the arithmetic unit 12. And this first rolled material
And the roll rotation speed v
Calculation of advanced rate correction coefficient C based on R and advanced rate f
Equation (5) is used to control the leading end of the next rolled material.
The advanced rate correction coefficient C used for control is obtained. Also, the above sheet speed
The pressure obtained from the actual measured value v0 of the degree and the distance L / the actual measured value v0
Based on the actual transfer time t of the leading end of the rolled material,
According to the equation (6), which is the equation for calculating the speed rate a, the next rolling material
An acceleration rate a used for controlling the tip portion is obtained. And on
It is a plate speed model formula using the advance rate correction coefficient C.
According to the equation (4), the sheet speed of the leading end portion of the next rolled material is
A predicted value can be determined. Also, the prediction of this plate speed
Is a transport time model formula using the value and the acceleration rate a.
According to the equation (3), the transfer time of the leading end portion of the next rolled material is
A predicted value can be determined. After that, repeat the above operation
return.

As described above, according to the first embodiment, the plate speed (initial plate speed) of the leading end portion of the first rolled material is also increased for the leading end portion of the rolled material cooled while being accelerated. Measured value of
And so performs learning calculation to correct the acceleration rate and advanced rate based on the actual value of the transport time, the tip portion of the next rolling material
The accuracy of predicting the transfer time of the rolled material can be improved, and the accuracy of controlling the winding temperature of the rolled material for a long time can be improved.

[0027] Example2.  FIG. 3 is a block diagram showing a control state according to the second embodiment of the present invention.
You. First, the speed correction device 12, the temperature calculation device 13, and the cold
Each calculation unit of the rejection pattern determination unit 14 has a model formula
The physical property values, model constants, initial values of variables, etc.
It is assumed that it is stored in advance. At this time, specific heat, specific gravity
The values of physical properties such as
Stored as stratified data. Rolled material tip
When it reaches the winding machine 4, the exit speed of the finishing mill and the winding
The picking speed is given as an input value to the speed correcting device 12.
As mentioned earlier,Advanced rate correction coefficient C and acceleration rate aSought
Can be I was askedAdvanced rate correction coefficient C and acceleration rate aIs the
Calculation of temperature and determination of cooling pattern after the middle part of rolled material
Used for calculations. In the temperature calculation device 13, the speed correction performance
Plate speed and transport time obtained by the arithmetic unit 12,Goal volume
Removal temperature, finish rolling mill exit temperature, finish rolling mill exit plate
The thickness and winding temperature are entered, and the temperature
The lower volume is calculated. The cooling pattern determination device 14
Make sure that each water injection bath is set so that the measured winding temperature matches the target winding temperature.
The amount of water injected and the water injection pattern are determined.

[0028] That is, in Example 2, the leading end of the current rolled material is used.
The actual measured value v0 of the plate speed (initial plate speed) of the part and the roll speed
Based on the rotation speed vR and the advance rate f, the advance rate correction coefficient
According to equation (5), which is a calculation equation of C, the intermediate value of the rolled material of this time is
The advanced rate correction coefficient C used for the control after the part is obtained. Ma
In addition, the actual measured value v0 of the plate speed and the distance L / the actual measured value v0
The actual value t of the transport time of the leading end of the rolled material obtained this time and
Is calculated based on the following equation (6), which is an equation for calculating the acceleration rate a:
The acceleration rate a used for the control of the intermediate portion of the next rolled material and thereafter is
Ask. Then, using the advanced rate correction coefficient C, the plate speed
According to the model formula (4), the intermediate part of the rolled material
It is possible to calculate the predicted value of the plate speed (initial plate speed) after
it can. Also, the predicted value of the plate speed and the acceleration rate a are
Using the transfer time model formula (3),
Obtaining the predicted value of the transfer time after the middle part of the rolled material
Can be.

As described above, according to the second embodiment, the rolling
Actual measured value and transport of the plate speed (initial plate speed) at the tip of the material
Based on the actual value of time, the
A learning calculation to correct the acceleration rate and advance rate used for
Therefore, the prediction accuracy of the transfer time after the middle part of the rolled material is
Thus, the winding temperature control accuracy can be improved over the entire area of the rolled material.

[0030] Example3.  FIG. 4 is a block diagram showing a control state according to the third embodiment of the present invention.
You. First, the speed correction device 12, the temperature calculation device 13, and the cold
Each calculation unit of the rejection pattern determination unit 14 has a model formula
The physical property values, model constants, initial values of variables, etc.
It is assumed that it is stored in advance. At this time, specific heat, specific gravity
The values of physical properties such as
Stored as stratified data. Rolled material tip
When it reaches the winding machine 4, the exit speed of the finishing mill and the winding
The picking speed is given as an input value to the speed correcting device 12.
As mentioned earlier,Advanced rate correction coefficient C and acceleration rate aSought
Can be. RequestWas calledAdvanced rate correction coefficient C and acceleration rate aIs next
As initial value of setup control of rolled material to be cooled
Used. In the temperature calculation device 13, a speed correction calculation device
The board speed and the transport time obtained in step 12,Target winding temperature
Degree, exit temperature of finishing mill, thickness of exit side of finishing mill and
The winding temperature is entered, and from these values, the temperature drop
Is calculated. In the cooling pattern determination device 14, the predicted winding
Of each water injection bank so that the cooling temperature matches the target winding temperature.
The water injection amount and water injection pattern are determined. At this time,
Picking temperature and windingSideActual value detected by thermometer 10
To correct the cooling capacity correction coefficient K. I was asked
The value is the initial value of the setup control of the rolled material to be cooled next
Used as

As described above, according to the third embodiment, the acceleration rate of the leading end portion of the rolled material that is cooled while being accelerated is also determined based on the actual values of the previous winding speed and the winding temperature of the rolled material. Since the learning calculation for correcting the advanced rate and the cooling capacity correction coefficient is performed, it is possible to improve the winding temperature control accuracy over a long period of time.

[0032] Example4.  FIG. 5 is a block diagram showing a control state according to the fourth embodiment of the present invention.
You. First, the speed correction device 12, the temperature calculation device 13, and the cold
Each calculation unit of the rejection pattern determination unit 14 has a model formula
The physical property values, model constants, initial values of variables, etc.
It is assumed that it is stored in advance. At this time, specific heat, specific gravity
The values of physical properties such as
Stored as stratified data. Rolled material tip
When it reaches the winding machine 4, the exit speed of the finishing mill and the winding
The picking speed is given as an input value to the speed correcting device 12.
As mentioned earlier,Advanced rate correction coefficient C and acceleration rate aSought
Can be. RequestWas calledAdvanced rate correction coefficient C and acceleration rate aIs the
Calculation of temperature and determination of cooling pattern after the middle part of rolled material
Used for calculations. In the temperature calculation device 13, the speed correction performance
Plate speed and transport time obtained by the arithmetic unit 12,Goal volume
Removal temperature, finish rolling mill exit temperature, finish rolling mill exit plate
The thickness and winding temperature are entered, and the temperature
The lower volume is calculated. The cooling pattern determination device 14
Make sure that each water injection bath is set so that the measured winding temperature matches the target winding temperature.
The amount of water injected and the water injection pattern are determined. At this time,
Predicted winding temperature and windingSideDetected by thermometer 10
By comparing the actual values, as described above, the cooling capacity correction coefficient K
To correct. The calculated value is the value after the middle part of the rolled material.
Used for cooling pattern determination calculation.

As described above, according to the fourth embodiment, the acceleration rate, the advance rate, and the cooling capacity correction coefficient are corrected based on the actual values of the winding speed and the winding temperature during the previous periodic calculation. Since the learning calculation is performed, it is possible to improve the winding temperature control accuracy over the entire area of the rolled material.

[0034]

As described above, according to the first aspect of the present invention,
Improved accuracy in predicting the transport time of the leading edge of the next rolled material
To improve the accuracy of controlling the rolling temperature of rolled material over a long period of time
Can be done. According to the invention of claim 2, a rolled material
Of the transfer time after the middle part of
To improve winding temperature control accuracy over the entire area
Can be.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a cooling device according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a control state of the cooling device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a control state of a cooling device according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a control state of a cooling device according to a third embodiment of the present invention.

FIG. 5 is a block diagram showing a control state of a cooling device according to a fourth embodiment of the present invention.

FIG. 6 is a configuration diagram of a conventional cooling device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolled material 2 Finish rolling mill (rolling part) 3 Run-out table 4 Winding machine (winding part) 5a Cooling bank (cooling part) 5b Cooling bank for fine adjustment (cooling part) 6 Cooling control device 7 Finishing exit speed meter Reference Signs List 8 Thickness gauge 9 Finishing-out side thermometer 10 Winding-side thermometer 11 Winding-side speedometer 12 Speed correction calculating device 13 Temperature calculating device 14 Cooling pattern determining device 15 Valve opening and closing device

Claims (2)

(57) [Claims] 1. Hot rolled rolled materialTemperature model formula
In the method of controlling the cooling using Rolled material tip measured in rolling control of first rolled material
Measurement of strip speed and roll speed of finishing mill
To control the leading edge of the next rolled material based on the
Determine the advanced rate correction coefficient to be used and measure the above plate speed
Value and the actual value of the transport time of the leading end of the first rolled material
Used to control the leading end of the next rolled material based on the acceleration
Rate and calculate the next rate based on the advanced rate correction coefficient.
The sheet speed at the leading end of the rolled material of
Of the next rolled material based on the obtained sheet speed and the above acceleration rate
Predict the transport time of the end part The feature is that
Control method for cooling rolled material. 2. Rolled material that has been hot finishedTemperature model formula
In the method of controlling the cooling using The tip of the rolled material measured in the rolling control of this rolled material
Measurement of strip speed and roll speed of finishing mill
Control of the middle part of the rolled material based on
Calculate the advanced rate correction coefficient used for
Actual measured values and actual results of the transport time of the leading end of the rolled material
Value to control the middle and subsequent parts of the rolled material
Acceleration rate, and then calculate the advanced rate
And predict the sheet speed after the middle part of the rolled material
Based on the predicted plate speed and the acceleration rate,
The transfer time after the middle part of the rolled material Like
A method for controlling the cooling of a rolled material.