JPH07303909A - Device for automaticaly correcting setup of width in rough hot rolling - Google Patents

Abstract

PURPOSE:To improve the accuracy of width of a rough bar on the outlet side of rough hot rolling and to raise the yield of rough bar rolling. CONSTITUTION:This device is provided with an estimating means 8 for estimating and calculating a spread rate alpha and an effective edging rate eta in a roughing mill which consists of a horizontal mill R2 and an edger RE using a linear combination equation based on the rolling condition, measured width and measured temp. of the rough bar, edging setting means 9, 2, 20, 3 for deciding an opening degree to be set to the edger RE based on a calculated value, setting a motor-driven opening degree as the opening degree and further adjusting the hydraulic opening degree by the amount of compensation for an error in setting and adaptive correcting means 18 for online adaptively correcting the parameters of the linear combination equation using the actual value of width on the outlet side of the roughing mill. In this way, both average value and variation of width deviation on the outlet side of the rough hot rolling are greatly reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to hot rough rolling by means of a rough rolling mill comprising a horizontal rolling mill and a width rolling mill (hereinafter referred to as edger), and more particularly to a width rolling mill equipped with a hydraulic width reduction device. The present invention relates to a strip width automatic setup correction in hot rough rolling used.

[0002]

2. Description of the Related Art Conventionally, in controlling the average strip width of a rough bar during hot rough rolling, when the initial opening of a horizontal rolling mill and an edger is calculated using a width prediction model formula, The rough width correction value (coarse width margin amount) is calculated and added to the target bar width so that the rough side bar width does not fall below the target bar width due to the modeling error in 1. But with this method,
In a mill consisting of multiple rough rolling mills, it is impossible to eliminate the model error, and it is necessary to automatically correct the setup in the middle. As for the trend of automatic setup correction, most of them use the actual values of the intermediate width gauge and edger load data to correct the edger opening of the latter stage and the hydraulic pressure reduction position of the hydraulic width reduction device (hereinafter referred to as the oil column opening). It is a method to do.

For example, in the "sheet width control method in hot rolling" disclosed in Japanese Patent Laid-Open No. 62-24809, the width variation on the final stage feeding side is predicted based on the load data of the front stage edger, and the latter stage Correct the electric opening setup of the edger. Further, Japanese Patent Application Laid-Open No. 61-249615 discloses a "plate width control device" which determines an electric opening by using intermediate width meter data.

[0004]

However, the above-mentioned JP-A-62-24809 and JP-A-61-249.
In Japanese Patent No. 615, attention is not paid to an error in the opening setting of the electric edger, and 100% of the edger opening setting in the subsequent stage is relied upon. However, an error corresponding to the precision of stopping the electric edger occurs, and sufficient precision cannot be obtained. Further, since there is no means for adaptively correcting the width expansion model using the actual width on the output side of the rough rolling mill, there is a problem that the rolling characteristics are weak against changes with time and the width accuracy deteriorates with time. .

In the conventional plate width control method as described above, as long as the stopping accuracy of the electric edger is about ± 0.5 mm,
No matter how the automatic setup correction (automatic adjustment of the opening setting) is performed, it is permanently impossible to adjust the rough bar width on the output side of the rough rolling mill in units of 0.1 mm. If automatic setup correction is performed only by the hydraulic pressure reducer without using an electric edger, it is presumed that the width reduction amount can be secured with the same accuracy as that of the present invention described later. Since the column opening greatly moves in units of several mm, the plate width control range for skid mark control, necking control, etc. in the plate cannot be taken, and the in-plate control becomes impossible. Further, since there is no adaptive correction function, once a model error occurs, the error remains permanently, and the model must be adjusted regularly.

The present invention has been made in order to solve the above-mentioned conventional problems, and secures the width reduction amount with high accuracy and minimizes the compensation amount of the hydraulic pressure reduction device at this time. (± 1 mm or less), the first purpose is to avoid the restrictions on the strip width control in the strip and further to prevent the accuracy deterioration due to the change with time of the rolling characteristics of the rough rolling mill. The second purpose is to simultaneously reduce and improve the average bar width accuracy (average value / variation) and the yield on the output side of the rough rolling process, and the third purpose is to perform these without operator intervention. And

[0007]

SUMMARY OF THE INVENTION A strip width automatic correction device for hot rough rolling of the present invention is a horizontal rolling mill (R
2), and a rough rolling mill (R2, RE) including a width rolling mill (RE) provided with a hydraulic width reduction device; the width of the rough bar (S) rolled by the rough rolling mill (R2, RE), and Width measuring means (4,5) and temperature measuring means (6) for measuring temperature in real time and generating width information and temperature information; based on the width information and temperature information, a linear combination formula of physical property model is used Prediction means (8) for predicting and calculating the width spread ratio and the effective width reduction ratio in the rough rolling mill; based on the width spread ratio and the effective width reduction ratio, the rough rolling mill exit side width is set to a predetermined target bar. Calculate the amount of width reduction required to reach the width, determine the electric opening corresponding to the width reduction and set it in the width rolling mill, and the error of the stop accuracy in the setting of the electric opening. The width reduction setting means (9, 20, 2, 3) for adjusting the hydraulic reduction position of the hydraulic width reduction device to compensate for the The actual value of the width expansion ratio is calculated based on the actual width on the exit side of the rough rolling mill obtained from the width information in (5), and using it, the linear parameters of the linear combination equation of the physical property model are plural forgetting factors / weights. An adaptive correction means (18) for performing online adaptive correction by a sequential recursive least squares filter. In addition, in order to facilitate understanding, the function blocks shown in FIG. 1 and FIG.
The corresponding reference numerals are added for reference.

[0008]

[Operation] First, in the predicting means (8), based on the actual width and temperature of the rough rolling mill entrance side obtained from the width measuring means (4) and the temperature measuring means (6), the rough rolling mill (R2, RE) In order to set the exit side width to a predetermined target bar width, first, the width expansion rate and the effective width reduction rate are predicted and calculated. At this time, the width expansion rate is calculated using a physical property model and a linear combination formula of the size of the coarse bar.

The width reduction setting means (9, 20, 2, 3) calculates the width reduction amount of the width rolling mill (RE) based on the calculated width expansion ratio and effective width reduction ratio, and the width rolling mill The electric opening of (RE) is determined and this electric opening is set in the width rolling mill (RE). Furthermore, width rolling mill
After (RE) is moved to the opening position by electric operation, that is, when the setting of the electric opening is completed, the actual opening (actual opening) is collected and the stop error at that time, that is, the setting error is obtained, and the error is calculated. The oil column opening of the hydraulic pressure reduction device (pressure reduction position by the hydraulic cylinder; horizontal direction) is set again in order to make it zero. That is, the oil column opening is adjusted. This compensates for the electric opening setting error in units of 0.1 mm. As a result, the width reduction amount surely agrees with the calculated value.

The adaptive correcting means (18) collects the actual width of the rough bar rolled by the rough rolling mill (R2, RE) by the width measuring means (5),
The actual width expansion ratio is calculated based on the width difference (width-canceling amount) on the input and output sides of the rough rolling mill (R2, RE), the horizontal reduction amount, the width reduction amount, and the effective width reduction ratio. Then, using this actual width spread rate, the parameters of the linear combination formula for predicting the width spread rate are updated.

In this way, while compensating the electric opening stop accuracy of the electric edger (RE), that is, the setting accuracy by the oil column opening,
In addition, by adding an online adaptive correction mechanism for the width expansion ratio of the rough bar, it is possible to dramatically improve the accuracy of the average width of the rough bar on the exit side of the rough rolling mill (R2, RE).

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings. The strip width setup automatic correction device in hot rough rolling of the present invention will be described in detail below with reference to the drawings.

[0013]

1 shows the system configuration of an embodiment of the present invention, FIG. 2 shows the function of the control computer 1 shown in FIG. 1, and FIG. 3 shows the rough rolling machine shown in FIG. (R2 + R
E) shows the width expansion ratio α and the effective width reduction ratio η of the rough bar S, and FIG. 4 shows the setting accuracy of the electric opening of the electric edger RE shown in FIG. 1, that is, the stopping accuracy. In this embodiment, as shown in FIG. 1, a horizontal rolling mill (hereinafter referred to as horizontal mill) R
2, a width reduction device (edger) RE equipped with a hydraulic width reduction device, and a control computer 1, an electric edger control device 2, a hydraulic pressure reduction control device 3, an entrance side width gauge 4,
It is realized by the outlet side width gauge 5 and the inlet side thermometer 6, and in the control computer 1, the coarse bar S has a horizontal mill R1 / horizontal mill R.
2 / Before rolling by the edger RE, the initial opening of the horizontal mill R1 / horizontal mill R2 / edger RE is calculated in advance, and the initial opening of the edger RE is calculated via the electric edger control device 2. Set to Edger RE. The electric edger control device 2 drives a motor for driving the edger RE in the width direction so that the initial opening degree indicated by the control computer 1 is reached.

The width gauges 4 and 5 installed on the outlet side of the horizontal mills R1 and R2 are arranged so that when the rough bar S passes through the width gauges 4 and 5 during rolling on the horizontal mills R1 and R2, The width is measured using light and a CCD camera, and the measured value (actual width) is given to the control computer 1. A thermometer 6 installed at substantially the same position as the width meter 4 measures the temperature of the rough bar S during rolling by the horizontal mill R1 and gives the measured value to the control computer 1. The control computer 1 samples and collects these measurement data at regular time intervals. Then, based on the collected data, the average plate width actual values on the entrance side (the exit side of R1) and the exit side of the horizontal mill R2 are calculated, and the edger
The opening of RE is set and the parameters of the model formula (linear combination formula) are adaptively corrected online.

Next, the internal processing function of the control computer 1 for performing such plate width setup (opening setting for plate width setting) control will be described with reference to FIG. 2. First, FIG. The definition of the width expansion ratio α and the effective width reduction ratio η, and the relationship between the inlet side width and the outlet side width of the rough bar S of the rough rolling mill including the edger RE and the horizontal mill R2 will be described.

The spread ratio α ((a) in FIG. 3) shows the spread ratio of the coarse bar S in the width direction when it is rolled by a horizontal mill and is represented by the following formula: α = (W _out − W _in ) / Δh (1) Where, W _in : horizontal mill inlet side width W _out : horizontal mill outlet side width Δh: horizontal rolling reduction (= h _in −h _out ).

The effective width reduction ratio η ((b) of FIG. 3)
Shows that when the width is reduced by the edger RE, the part that rises in the thickness direction (marked with * in Fig. 3) returns to the width direction by horizontal reduction, and as a result, the initial amount of width killing cannot be secured. Yes, it is the ratio of the actual width reduction with respect to the initial width reduction amount and is represented by the following formula: η = (W _in −W _out ) / ΔE (2) where W _in : Edger entry side width W _out : Horizontal mill exit side width ΔE: Width reduction (= W _in −E) E: Edger opening degree.

The relationship between the entrance side width W _in and the exit side width W _out of the rough rolling mill composed of the edger RE and the horizontal mill R2 is expressed by the linear combination of the width expansion and the effective width reduction. It is expressed as follows: W _out = W _in −η × ΔE + α × Δh (3).

As shown in FIG. 2, the control computer 1 includes the data processing functions of the following three systems: Electric opening degree setting 19: Actual output of the coarse bar S from the mill exit side in the horizontal mill R1. The width and temperature are used to predict and calculate the width expansion rate α and the effective width reduction rate η, and using these, the horizontal mill R2 exit side width is predicted to calculate the width reduction amount, and the width reduction amount corresponding to the width reduction amount Setting the electric opening of the edger RE on the entry side of the horizontal mill R2, Oil column opening setting 20: Stop error of electric opening (setting error)
Set (adjust) the oil column opening in order to compensate for it. Learning 18: The actual width spread ratio α _REAL is calculated by taking in the average strip width actual value after rolling in the horizontal mill R2, and the width spread ratio α is calculated. The linear parameters of the linear model equation for calculation are updated sequentially.

In the electric opening setting block 19, the width measurement value (width actual value) by the width meter 4 and the temperature measurement value (temperature actual value) by the width meter 4 collected during rolling of the rough bar S by the horizontal mill R1. Value) from the output width of the horizontal mill R1 / temperature collection unit 1
At 0, data processing (noise removal, filtering) is performed to obtain an average value, and based on the actual average width and the actual average temperature,
The width spread rate predicting unit 8 predicts the width spread rate α by the linear combination formula shown below. At this time, the learning parameter file 1
Adaptive correction parameters from 1 to slab data file 7
Material, roll diameter and thickness data are extracted from.

[0021]

[Equation 4]

Here, D _H : horizontal roll diameter A: constant B: terms caused by material and temperature C ₁ , C ₂ : adaptive correction parameters (three types are prepared corresponding to the target bar width).

At this time, the effective width reduction η is also predicted at the same time, which is a static (fixed parameter) mathematical expression.

[0024]

[Equation 5]

C ₁ , C ₂ : Constants (3 classifications are prepared corresponding to the target bar width).

Based on the predicted width expansion ratio α and effective width reduction ratio η, in order to obtain the target bar width on the outlet side of the horizontal mill R2,
The width reduction amount at the edger RE is calculated (back calculation of Expression 3).

ΔE = (W _in −W _out + α × Δh) / η (6) Then, in the electric opening setting unit 9, the coarse bar S is set to the target bar width on the exit side of the horizontal mill R2. The edger RE opening amount to be calculated is calculated by the following formula, and the value is given to the electric edger control device 2,
The opening represented by the opening amount is set: E = W _in −ΔE (7).

Next, in the oil column opening degree setting block 20, the actual opening degree is collected at the timing when the opening degree setting is completed by the electric edger control device 2 and the target opening degree set by the electric opening degree setting unit 9 is set. Is calculated (stop error calculation unit 16): ε = actual opening-opening target (8).

The value of ε calculated here is a cause of variation in the output width of the horizontal mill R2, and the actual value is about 0.34 mm, as shown in FIG. Therefore, in order to set ε → 0, the oil column opening degree setting unit 17 calculates the oil column opening degree P _oil1 as follows, and supplies this to the hydraulic pressure reduction device 3 to set the oil column opening degree: P _oil1 = P _oil1 + ε (9) P _{oil1 in} the first term on the right side is the oil column opening before this setting, ε is the adjustment amount that should be changed for this setting, and P _{oil1 on} the left side is the current It is the oil column opening set value.

Finally, in the learning block 18, the actual width of the rough bar S rolled by the horizontal mill R2 is collected via the above two setting blocks 19 and 20, and the horizontal mill R1 is collected.
The average width is calculated in the same manner as the data processing of the output side width of, and the actual width spread rate α _REAL is calculated based on the average width (actual width spread rate calculation unit 13): α _REAL = {η × ΔE− (W _out −W _in )} / Δh (10) Here, W _out : Outer side actual width (average value) of the horizontal mill R2 W _in : Inward side actual width of the horizontal mill R2 (Average value).

Based on the actual width spread rate α _REAL and the predicted width spread rate α predicted by the width spread rate predicting section 8, the adaptive parameters (C ₁ , C ₂ ) of the equation (4) are calculated by the online adaptive correcting section 14.
Is adaptively corrected by the recursive least squares method with a forgetting factor. However, at this time, the parameters are modified only when the following adaptive modification conditions are satisfied.

[Adaptive correction conditions] The collection of the outlet width (average value) of the horizontal mill R2 is normal, the outlet width of the horizontal mill R1 is normally collected, | R2 output side actual width-calculation width | < 5 mm: Due to abnormal data deletion, predicted α value -10% ≤ actual value α _REAL value ≤ predicted α value + 10
%, And | RE electric opening setting calculation value−actual value | ≦ 1 mm.

The parameters updated by the adaptive correction are
It is stored in the learning parameter file 11. The adaptive correction by the recursive least squares method with a forgetting factor is effective when the model parameter of the target process is time-varying (temporal change: for example, roll diameter fluctuation due to roll temperature rise).

In this way, the model correction is automatically performed on-line, and the width variation of the coarse bar S on the output side of the horizontal mill R2,
That is, the width deviation is suppressed.

[0035]

In the hot rough rolling strip width automatic setup apparatus of the present invention, the rough rolling mill (RE + R2) is used based on the measured value (actual value) of the intermediate sensor (width gauge 4, thermometer 6). The width spread rate α and the effective width reduction rate η are predicted and calculated so that the edger (R
E) The opening that should be set is calculated, and the stop accuracy (setting accuracy) of the electric opening is compensated by modifying the oil column opening, so the calculated set opening and the actual set opening (actual) Error is reduced (mean value x of error ≈0 is realized), and variation in preset opening is reduced (error deviation value σ is reduced). Further, since the actual width data measured by the width gauge (5) installed on the output side of the rough rolling mill is used, the linear combination linear parameter for predictive calculation of the width spread rate is adaptively corrected online. The width deviation of the bar (S) substantially converges to zero.

Since the present invention combines these,
Both the average value and the variation of the width deviation on the output side of the hot rolling process are dramatically reduced, that is, the accuracy of the width of the rough bar plate is dramatically improved, and the yield in the rough bar rolling is improved.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing functions of a control computer 1 shown in FIG.

FIG. 3 (a) is a plan view and a side view of a rough bar during rolling in a horizontal mill, showing the dimensions of each rough bar that defines the width spread rate α. (B) is an edger before rolling,
It is a transverse cross-sectional view of the rough bar during and after rolling, showing the dimensions of each part of the rough bar, which defines the effective width reduction η.

FIG. 4 is a graph showing a statistical value of a stop accuracy record, that is, an electric opening setting error of the electric edger RE shown in FIG.

[Explanation of symbols]

S: Coarse bar R1: NO. 1 horizontal mill R2: NO. 2 Horizontal mill RE: Edger 1: Control computer 2: Electric edger control device 3: Hydraulic pressure reduction device 4: Width gauge 5: Width gauge 6: Thermometer 7: Slab data file 8: Width spread prediction unit 9: Electric opening Setting unit 10: Output side width / temperature collection unit 11: Learning parameter file 12: Output side width collection unit 13: Actual width spread rate calculation unit 14: Online adaptive correction unit 15: Electric opening degree actual result collection unit 16: Stop error calculation Part 17: Oil column opening setting part 18: Learning block 19: Electric opening setting block 20: Oil column opening setting block

Claims (1)

[Claims] 1. A rough rolling mill including a horizontal rolling mill and a width rolling mill provided with a hydraulic width reduction device; a width and a temperature of a rough bar rolled by the rough rolling mill are measured in real time, and width information and Width measuring means and temperature measuring means for generating temperature information; based on the width information and the temperature information, a width spread rate and an effective width reduction rate in the rough rolling mill are predicted and calculated using a linear combination equation of a physical property model. Prediction means: Calculates a width reduction amount required to bring the rough rolling mill output side width to a predetermined target bar width based on the width expansion ratio and the effective width reduction ratio, and determines the width reduction amount. Width reduction setting means for determining the corresponding electric opening and setting it in the width rolling mill, and adjusting the hydraulic pressure reduction position of the hydraulic width reduction device by the amount that compensates for the stop accuracy error in setting the electric opening. And the width information of the width measuring means The actual value of the width spread ratio was calculated based on the actual width of the rough rolling mill exit side obtained from the report, and the linear parameters of the linear combination equation of the physical property model were used to calculate multiple forgetting factors / weighted recursive least squares. An automatic plate width setup correction device in hot rough rolling, which comprises an adaptive correction means for performing online adaptive correction by a filter.