JPH0252114A - Shape control method and apparatus for sheet stock - Google Patents

Abstract

PURPOSE:To control a sheet crown at high speed with high accuracy by measuring the crown of the sheet stock on the outlet side of a rolling mill to operate a leveling, bender and shift, based on those results, by operating roll coolant quantity. CONSTITUTION:Sheet thickness of the sheet 6 to be rolled is measured by a crown meter 7, the sheet thickness distribution in the cross direction of the sheet is enciphered by a curve fitting 87. The deviation between the reference value of the sheet thickness given to a reference value setting section 81 is calculated by an adder 83 to input into a crown control section 84. The crown control section 84 decides each operating value to minimize the integrated value to square the difference between the product and sum as to the operating values influence coefficients and weight factors of leveling 21, benders 22, 23 and shifts 24, 25 at respective positions. To eliminate the residual deviation uncontrolled by the above-mentioned operating, the operating value for the roll coolant 26 is decided by the crown control section 84. Each control is performed organically, the sheet crown control is enabled at high speed with high accuracy.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention includes leveling, bending, shifting, and roll coolant as actuators for controlling the shape of a plate material, and rolling by these actuators. The present invention relates to a method and apparatus for controlling the shape of a plate material on the exit side.

In this specification, the shape of a plate is used as a concept that encompasses both the plate crown, which is known as the plate thickness distribution in the plate width direction, and the flatness, which is known as the elongation rate difference in the plate width direction. However, in the following, explanation will be given mainly by exemplifying the former case of a plate crown.

(Prior Art) Conventionally, exit side plate crown control of a rolling mill has been carried out, for example, by a method as shown in "Tetsu to Hagane", No. 3, 1988, pp. 77-84. That is, more specifically,
Roll bending force correction amount Δ to cancel the variation of the uniform load plate crown caused by the rolling load variation ΔP
This method calculates FCOIIp according to the following formula and corrects the roll pending force accordingly.

ΔC-Cp ・ΔP+Cf ・ΔF... (1) Δ
Fcomp--(Cp/Cf) ・ΔF... (2
) Here, Cp and Cf represent influence coefficients due to rolling load and roll pending force, respectively.

Furthermore, in order to prevent minute mutual interference when the control output changes, the rolling reduction correction amount Δs age from the plate thickness control device and the roll bending force correction amount ΔF coo from equation (2) are calculated.
p is made non-interfering, and the final corrected outputs ΔS nlc and ΔF nie are determined based on equation (3).

Here, A represents a matrix (2×2 dimensions) for deinterference. Further, the suffix "-1°" indicates the value at the time of the previous sampling output.

Furthermore, as shown in the above-mentioned document, a crown control method using a bare cross mill has also been implemented. In this control system, crown control is performed by adjusting the roll cross angle and roll bender force by:J3.

(Problems to be Solved by the Invention) The above-mentioned conventional control method is not a dynamic control performed based on the 71-1 fixed number from the plate crown meter on the exit side of the rolling mill, and Each actuator for control, such as leveling, work roll bender, intermediate roll bender, work roll shift,
Because it is not a plate crown control that uses intermediate roll shift, roll coolant, etc. in an organic manner,
This was insufficient from the viewpoint of high-precision and high-speed response control.

Therefore, an object of the present invention is to provide a method and apparatus for controlling the shape of a rolling mill with higher precision and faster response.

A second object of the present invention is to provide a shape control device for a rolling mill that can perform optimal control with higher precision and faster response.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the object mentioned above, the present invention provides a method to obtain the difference between a shape reference set by dividing the shape of a plate material into a plurality of positions and a shape measurement value corresponding thereto. The minimum value is the square of the difference between the product of the shape deviation and the weighting coefficient at the relevant position and the sum of the products of the operation amount, influence coefficient, and weighting coefficient at the relevant position for leveling, bending, and shifting, and integrated for each position. Determine the leveling, bender, and shift operation amounts so that the deviation between the shape deviation for each position and the sum of each operation amount and influence coefficient is the product of the roll coolant operation amount and influence coefficient. The method is characterized in that the amount of operation of the roll coolant is determined so as to match each other.

Furthermore, the present invention is characterized in that the output of calculations in each control process is determined by inference by an inference mechanism based on a knowledge base in which knowledge and experience regarding control of the shape of plate materials are made into rules.

(Function) In order to control the crown or flatness of the outlet plate of the rolling mill to a predetermined value, the deviation between the shape standard and the actual shape according to each rolling schedule is determined, and the rolling mill leveling,
By using the bender and shift influence coefficients to organically determine the operation amount of the leveling, bender, and shift actuators, and determine the roll coolant operation amount in relation to this, each actuator is organically linked. It is possible to perform optimal shape control at high speed and obtain plate materials with good shapes.

In addition, by accumulating the knowledge and experience of engineers and operators regarding shape control as a knowledge base and executing intelligent control using this knowledge through an inference mechanism, better shape control can be achieved.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 2 schematically shows the overall configuration of the present invention.

Rolling mill 1 with 5 sets of stand mills arranged in tandem,
2, 3, 4, and 5 in the direction of the arrow Q, the plate 6 to be rolled is rolled into a predetermined shape, and in the embodiment described below, a predetermined plate crown.

Here, a six-high rolling mill is illustrated as the rolling mill for each stand. The plate crown of the plate material 6 to be rolled is detected by a crown 717 disposed on the exit side of the rolling mill, and is input to the crown control device 8. The crown gauge 7 is composed of, for example, an X-ray thickness gauge, and scans the plate material 6 to be rolled in the width direction of the plate material 6 to determine the plate thickness Ar1. The crown control device 8 is
The actuators 11, 12, 13 and 14, 15 are respectively controlled so that the plate crown determined by the crown nid 7 coincides with the crown standard set therein.

As shown in FIG. 3, rolling mills 1 to 5 each have a pair of work rolls wt and wb arranged in order from the inside.

Intermediate rolls It, Ib, and backup rolls Bt
, Bb. As actuators for plate crown control, leveling 21 is provided to lower the backup roll Bt on the drive side and the work side, respectively, as conceptually shown by the arrows, and the work rolls wt and wb are provided with a work roll bender. 22, an intermediate roll bender 23 is provided for the intermediate rolls It and Ib, and further a work roll wt is provided.
, wb are provided with a work roll shift 24, and intermediate rolls It, Ib are provided with an intermediate roll shift 25. Each of the leveling, roll bending and roll shifting can be constructed using a known actuator. As is well known, the roll bender acts on the rolls in the direction of the thickness of the plate material 6 to be rolled, and the roll shift acts to shift the rolls in the width direction of the plate.

Although the roll coolant provided as an actuator is not shown in FIG. 3, a large number of roll cooling water nozzles are arranged along the width direction of the sheet to cool the roll.
It is configured so that the rolls can be locally cooled by individually controlling on/off the cooling water injected from those nozzles.

FIG. 1 shows the detailed configuration of the crown control device rt8. In addition, here, the rolling mills 1 to 5 are represented by the reference numeral 10, and each actuator is represented by the reference numeral 20. Further, the roll coolant is designated by the reference numeral 26.

Generally speaking, the crown control device 8 in FIG. That is, a crown deviation is determined, and based on this crown deviation, the leveling 21, work roll bender 22, intermediate roll bender 23, and work roll shift 24 are performed so that the sum of squares or the sum of squares is minimized via the crown control unit 84 based on this crown deviation. In addition to operating the intermediate roll shift 25, the roll coolant 26 is also operated in connection therewith to control the temporary crown of the plate material 6 to be rolled.

Now, in the rolling schedule setting section 88, the steel type, plate thickness, plate width, roll gap, roll speed, actuator operation amount, etc. are set. Rolling schedule setting section 88
According to the rolling schedule set in , the crown reference setting section 81 provides a desired plate crown CR(x), that is, a plate thickness reference corresponding to the position X in the plate width direction. The curve fitting 87 formulates the plate thickness distributed in the plate width direction measured by the crown meter 7. Here, the plate thickness detection value C' (
x). Plate thickness standard CR(x) for each position
And the deviation of the plate thickness detection value C' (x), that is, the plate thickness deviation ΔC (x) is obtained in the adder 83 as ΔC (x) - CR (x) - C' (x) (1) , is input to the crown control section 84.

The crown control unit 84 first calculates the amount of operation of each actuator that minimizes J as follows.

However, in equation (2), B: plate width η(X)1 weighting coefficient K (X), K (X), K (X), K (
X), ni5 (X):! 1i coefficient Δy1 Ni-leveling operation amount ΔY2 'Work roll bending operation amount ΔY3'
Intermediate roll bending operation amount ΔY4 'Work roll shift operation amount Y5' Intermediate roll shift operation amount From equation (2), the operation amount of each actuator can be determined as follows.

Equations (3) to (7) must be solved simultaneously, but there are five equations and the unknowns are Δy, Δy2Δy3, . Δy4. Δ
Since there are 5 pieces of y5, the solution can be found.

Next, the operation amount of the roll coolant 26 is set as follows,
I ask.

Δyl, ΔY2°Δy3. determined by equations (3) to (7).
Δ'l'4. Using Δy5, find.

In equation (8), Δε(X) is the plate crown deviation,
This is the amount that could not be controlled by the leveling 21, work roll bender 22, intermediate roll bender 23, work roll shift 24, and intermediate roll shift 25. Therefore, this amount is controlled by the roll coolant 26.

This can be expressed as a formula as follows.

Δε(x)=K(x) ・ΔY6(x)−(9
) smile Δy6 (X) is the roll coolant operation amount Ke
(x) is the plate crown influence coefficient of the roll coolant operation amount.

The operation amount of the roll coolant 26 can be determined from equation (9) as shown in step 2.

The influence coefficients in equations (2) to (9) can be calculated using well-known rolling theory. For example, it can be calculated according to the document "Theory and Practice of Plate Rolling" (September 1, 1980, Iron and Steel Institute of Japan, Tsuji Corporation).

Returning to FIG. 3, the influence coefficients of equations (2) to (9) are calculated by the influence coefficient calculation unit 8B using the rolling schedule from the rolling schedule setting unit 88 as manual input, and are input to the crown control unit 84 manually.

The crown control unit 84 controls the operation amounts Δy, Δy2°■ Δy3. Δy4. ΔY5. Δ! /6 (X) is subjected to an appropriate PID (proportional, integral, differential) operation and is provided to the selector 85. In this case, each constant of the PID is given from the influence coefficient calculating section 8B.

The selector 85 selects the actuator to be activated via the selector control unit 8C based on the rolling schedule from the rolling schedule setting unit 88 and various actual values of the rolling mill 10 manually input from the actual fAiA output unit 8F. do. In this regard, although not shown, the crown control section 84
(2) and (9) depending on the selection content of the selector 85.
Select the actuator term in Eq.

The output of the selector 85 is added to the initial setting value set by the rolling schedule setting section 88 plus the amount of manual intervention from the manual intervention section 8E by an adder 86, and is manually input to the actuator 20. The leveling 21, work roll bender 22, intermediate roll bender 23, work roll shift 24, intermediate roll shift 25, and roll coolant 26 included in the actuator 20 are operated, thereby changing the plate crown of the rolled plate material 6 to a desired crown. Control to standard CR(x).

In the following, each actuator has been described as controlling a single rolling mill [10], but in reality, as shown in FIG. 2, the output of the crown control device 8 is transmitted to the actuator 11. 12. Control 1.3°14.15. In that case, the weighting coefficient η(X) of equation (2) is given to each stand, and the calculations of equations (2) to (9) are performed by the crown control device 8 for each stand.

As described above, by controlling each actuator in conjunction with rock fishing, it is possible to realize high-speed and highly accurate board crown control.

Next, an embodiment will be described in which optimal control is performed using the knowledge and experience of engineers and operators involved in rolling.

In FIG. 1, the crown standard setting section 81 is configured to set the n
! Crown M'% is output according to the four types, plate thickness, plate width, etc. The crown standard correction unit 8A corrects the Claran standard based on the application, the plate widthwise direction (m degrees), the knowledge and requests from the product coil users, and the like. These knowledge and requests are a type of know-how, and are preferably stored in the crown reference correction unit 8A as a knowledge base, and are inferred by the inference mechanism and added by the adder 82 as necessary. In that case, the influence coefficient calculation unit 8B outputs the influence coefficient of the crown control and the control constant of the PID control unit, but depending on the steel type, plate thickness, plate width, etc., the influence coefficient calculation unit 8B uses the know-how of rolling engineers and operators as a knowledge base. 8B
The information is stored in the system, inferred by an inference mechanism as necessary, and provided to the crown control unit 84. In addition, the selection control unit 8C
The actuator to be mainly used is determined based on the threading, acceleration/deceleration, rolling speed, FV4 types, plate thickness, plate width, etc. by inferring the internally stored database of knowledge and experience of engineers and operators. . Although not shown, the crown control section 84 performs calculations for the selected actuator according to formulas (2) to (9) in accordance with the selection content of the selection control section 8C.

The knowledge base and inference mechanism described above for the crown reference correction section 8A, influence coefficient calculation section 8B, and selection control section 8C will be further explained with reference to FIG.

In Figure 4, experts 91 such as engineers and operators
knowledge and experience are stored in the knowledge base 92. The knowledge and experience stored in the knowledge base 92 are converted by the knowledge compiler 93 into a knowledge internal representation 94 suitable for inference. The inference mechanism 95 performs matching of this knowledge internal representation 94 with the knowledge internal representation 94 in response to a request from the input/output section 96, and outputs the inference result to the input/output section 96.

An example of the contents of the knowledge base 92 and inference mechanism 94 in the above crown reference correction section 8A, influence coefficient calculation section 8B, and selection control section 8C will be described next.

First, make the rules modular and make them look like this: Note that "TDE33" at the beginning is the name of the tool.

Example of rule modularization: (1) Description rule module Plate crown in TDR33 Plate crown (Plate crown reference correction (Crown influence coefficient (Crown control constant) (Mode selection: Rule Plate crown reference correction (Plate thickness 2.51) (Plate width 1 [1001] (Application: Automobile) ?Th1cknass f<-2,0&&>-? w
fdth (<-L4001i>.

(call 5ub-2) ; Hereafter omitted (note) ;Comments are shown below.

; Procedure declaration (rulC Plate crown reference correction; Start-up conditions for correcting plate crown (schcm
a (Steel grade number crown standard correction calculation normal n4) (Note) ? Th1ckness etc.? Those with asterisks represent variables.

(procedure 5ub-2 ntry “SUB 2 ″ 0-Nle ” “00.0' type subroutine language r77 ); object-rlle (2) F called with the TDES3 expert system
ORTI? AN program Sυ13ROtJTI~l:sLll12COMMON
/TDIESDATA/CR(100), MO
DT (100) CRR (100) DO101-1,100 CR (+) - No T (+) This CRR (100) to
C0NTINUE ND (3) Calling the expert system in the main program REAL C1? (Ion), MODT (100),
CRI? (+00)COMMON/TDESDAT^
/CR, MODT, CRRCMODT, CRI?
SET (Omitted) Call the CTDES3 expert system and calculate CR(+).

CALL TDES3 TOP ND As described above, it is possible to achieve optimum round control for each rolling shape using the knowledge and experience of engineers and operators as a knowledge base.

In order to control the strip crown on the exit side of the rolling mill to a predetermined value, we will develop the strip crown standard according to the rolling schedule and the ability to correct it based on the knowledge and experience of engineers and operators. Calculate the temporary crown deviation using equation (1) by curve fitting the actual All value of the plate crown, and level it so that the value of equation (2) is minimized using the influence coefficients of rolling mill leveling, bender, and shift. , each operation port of the pengu shift is determined and the residual shown by equation (8) is controlled by the roll coolant operation amount shown by equation (9), and the influence coefficient, PID gain, control mode, etc. are also determined by engineers and operators. The knowledge and experience of the rolling mill can be utilized depending on the rolling conditions, and as a result, each actuator of the rolling mill can be controlled more optimally to obtain an optimal temporary crown.

Although the embodiment described above concerns plate crown control, by changing the temporary round meter 7 in the same embodiment to a flatness needle, flatness control can be performed in exactly the same manner as above. .

In addition, although it was explained that the target rolling mill was a 6-high mill (60-high mill), this could be a mill with any number of stages, such as a 2-high mill, 4-high mill, 8-high mill, 12-high mill, or 20-high mill. There may be.

Regarding actuators, leveling, work roll bender, intermediate roll bender, work roll shift,
Although a case has been described in which six intermediate roll shifts and six roll coolants are provided, these may be increased or decreased as appropriate. For example, there may be three such as leveling, work roll bender, and work roll shift, or conversely, a roll local deformation actuator, a backup roll bender, etc. may be added in addition to the above six.

〔Effect of the invention〕

As described above, according to the present invention, each actuator is organically related and controlled according to the calculation result of the calculation formula so as to reduce the deviation to zero based on the deviation related to the shape of the plate crown, etc., and has high precision with high speed response. Temporary crown control or instep flatness control can be performed.

In addition, we store the knowledge and experience of rolling engineers and operators involved in rolling as a knowledge base, and use it to correct standard values for plate crown or flatness, determine influence coefficients and PID gains, and select modes and process plate crowns or flatness. In flatness control, by inferring and using the W4 type, plate thickness, plate width, rolling conditions, etc., it is possible to achieve a more optimal $ control of plate crown or flatness.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing one embodiment of the present invention, Figure 2 is a layout diagram showing the overall configuration of a rolling mill and actuator control device, and Figure 3 is a front view showing the relationship between the rolling mill and actuator of each stand. 4 are explanatory diagrams of the knowledge base and the inference mechanism. 1 to 5, 10...Rolling mill, Wt, Wb...Work roll, It, Ib...Intermediate roll, Bt, Bb...
Backup roll, 6... Wave rolled plate material, 7... Crown meter, 8... Crown control device, 10... Rolling machine, 11 to 15. 20... Actuator, 21...
Leveling, 22... Work roll bender, 23.
... Intermediate roll bender, 24... Work roll shift, 25... Intermediate roll shift, 26... Roll coolant, 81... Crown standard setting section, 82. 8
3゜8D...addition section, 84...crown control section, 8
5... Selector, 86... Adder, 87... Curve fitting, 88... Rolling schedule setting section,
8A... Crown reference correction section, 8B... Influence coefficient calculation section, 8C... Selection control section, 8E... Manual intervention section,
8F...Achievement detection 92...Knowledge base,

Claims (1)

[Claims] 1. A method for controlling the shape of a plate, which includes a leveling, a bender, a shift, and a coolant as actuators for controlling the shape of the plate, and uses these actuators to control the shape of the plate on the exit side of a rolling mill, The product of the shape deviation obtained as the difference between the shape reference set by dividing the shape of the plate material into multiple positions and the corresponding shape measurement value, the weighting coefficient at the relevant position, and the leveling, bender, and shift operations at the relevant position. The amount of operation for leveling, bending, and shifting is determined so that the value obtained by integrating the square of the difference between the sum of the products of the amount, influence coefficient, and weighting coefficient for each position is minimized,
The operation amount of the roll coolant is determined so that the deviation between the shape deviation for each position and the sum of the products of the operation amounts and the influence coefficients matches the product of the operation amount of the roll coolant and the influence coefficient. A method for controlling the shape of plate materials. 2. The shape control of the plate material according to claim 1, wherein the output of the calculation in each control process is determined by inference by an inference mechanism based on a knowledge base in which knowledge and experience regarding shape control of the plate material is made into rules. Method. 3. In a plate shape control device that is equipped with leveling, bender, shift, and coolant as actuators for controlling the shape of the plate, and controls the shape of the plate on the exit side of the rolling mill by these actuators, it is possible to control the shape of the plate at multiple positions. The product of the shape deviation obtained as the difference between the shape standard set by dividing and the corresponding shape measurement value and the weighting coefficient at the relevant position, and the operation amount, influence coefficient, and weight at the relevant position of leveling, bender, and shift a first calculation means for determining each operation amount of leveling, bender, and shift such that the value obtained by integrating the square of the difference between the sum of the products of the coefficients for each position is minimized; a second calculation means for determining the manipulated variable of the roll coolant such that the deviation between the shape deviation and the sum of the products of the manipulated variables and the influence coefficients matches the product of the manipulated variable of the roll coolant and the influence coefficient; A plate shape control device characterized by comprising: 4. The first calculation means and the second calculation means each include a knowledge base that expresses knowledge and experience regarding shape control of plate materials as rules, and an inference mechanism that infers calculation outputs in each control process based on the knowledge base. 4. The plate shape control device according to claim 3, further comprising: