JP2023147370A - Leveling control method in hot rolling, leveling controller, hot rolling equipment, and method for manufacturing hot rolled steel strip - Google Patents

Abstract

To provide a leveling control method in hot rolling capable of stably controlling a meander of a rolled material by setting the timing of control start and its controlled variable for a rolling mill which is a control object.SOLUTION: A leveling control method in hot rolling includes: a first leveling correction amount calculation step (step S2) of calculating, after the tail end part of a rolled material S has passed through a rolling mill n(any of 1-N-3) from the top, a first leveling correct ion amount ΔLv1 on and after a control object rolling mill Fn+3, on the basis of a meander amount detected by the first meander detection device 13 installed between the rolling mill Fn and the rolling mill Fn+1; and a second leveling correction amount calculation step (step S4) of calculating, after the tail end part of a rolled material S has passed through a rolling mill Fn+2, a second leveling correction amount ΔLv2 on and after a control object rolling mill Fn+3, on the basis of a meander amount detected by a second meander detection device 16 installed between the rolling mill Fn+2 and the rolling mill Fn+3.SELECTED DRAWING: Figure 2

Description

The present invention relates to a leveling control method in hot rolling, a leveling control device, hot rolling equipment, and a method for manufacturing hot rolled steel strip.

Generally, in hot rolling equipment, a slab (rolled material) is heated to a predetermined temperature in a heating furnace, and the heated slab (rolled material) is roughly rolled to a predetermined thickness in a rough rolling mill to form a sheet bar (rolled material). ), and then the sheet bar (rolled material) is finish rolled to a predetermined thickness in a finish rolling facility equipped with a plurality of rolling mills. The finish-rolled sheet bar (rolled material) becomes a hot-rolled steel strip with a predetermined thickness, and is cooled by a runout table (cooling equipment) installed downstream of the finish rolling equipment. Thereafter, the hot rolled steel strip is manufactured by winding it into a coil shape using a winding machine.

Here, when rolling a rolled material in a finishing rolling facility equipped with multiple rolling mills, a phenomenon in which the widthwise position of the rolled material meanders toward the work side or drive side with respect to the center of the rolling mill. may occur. The drive side is the side where the drive motor for the rolling rolls is attached, and the work side is the side opposite to the drive side. When meandering occurs in the rolled material, the width end portions of the rolled material come into contact with the side guides, resulting in a buckling state and a squeezing phenomenon in which the rolled material is rolled. The occurrence of the squeezing phenomenon causes scratches on the rolling rolls, requiring maintenance or replacement work on the rolling rolls, and reducing productivity. Therefore, technology to control the meandering of the rolled material during continuous rolling and to pass the material through the mill center (center of the rolling mill) as much as possible is essential to prevent the above-mentioned troubles, improve productivity and This is important from the perspective of reducing production costs.

As methods for controlling such meandering of a rolled material, for example, a method for controlling the meandering of a tail end of a steel plate in hot finish rolling as shown in Patent Document 1, and a method for controlling meandering of a rolled steel plate as shown in Patent Document 2 are conventionally known. .
In the steel plate tail end meandering control method in hot finish rolling disclosed in Patent Document 1, a meandering detection device for detecting the amount of steel plate meandering is installed approximately in the center between the stands, and the meandering is controlled using the detected meandering amount. It is.

In addition, the meandering control method for a rolled steel plate disclosed in Patent Document 2 detects the amount of meandering with a meandering meter installed on the inlet side of the rolling mill, and changes the leveling amount to the amount obtained by multiplying the amount of meandering by a control gain. In the meandering control method, the control gain is determined according to the rolling load.
Note that leveling refers to the difference in opening between the roll gap on the work side and the roll gap on the drive side of the rolling mill.

Japanese Unexamined Patent Publication No. 7-144211 Japanese Patent Application Publication No. 2004-306125

However, these conventional methods for controlling the meandering of a tail end of a steel plate in hot finish rolling shown in Patent Document 1 and the method for controlling meandering of a rolled steel plate shown in Patent Document 2 have the following problems.
That is, in the case of the steel plate tail end meandering control method in hot finish rolling shown in Patent Document 1 and the rolled steel plate meandering control method shown in Patent Document 2, the start timing of meandering control is such that the tail end of the rolled material is controlled. This is after passing through the rolling mill in front of the rolling mill.
In other words, in the case of the steel plate tail end meandering control method in hot finish rolling disclosed in Patent Document 1, a meandering detection device is installed between the stand to be controlled and the stand in front of it, and the tail end of the rolled material is After passing through the previous stand, the optimal control amount for meandering control is calculated based on the meandering amount detected by the meandering detection device, and meandering is controlled by adjusting the reduction amount of the left and right chocks of the rolling roll using the leveling device. are doing.

In addition, in the case of the meandering control method for a rolled steel plate disclosed in Patent Document 2, a meandering meter is installed on the entry side of the rolling mill to be controlled, and the tail end of the rolled material is placed in the rolling mill in front of the rolling mill to be controlled. After passing through, the leveling amount is changed to the amount obtained by multiplying the meandering amount detected by the meandering meter by the control gain.
In this way, when the meandering control is started after the tail end of the rolled material has passed through the rolling mill in front of the rolling mill to be controlled, the following problem occurs.

The maximum control amount in leveling control is determined by the residence time of the tail end of the rolled material between the rolling mill to be controlled and the rolling mill in front of it, the command value of the control amount, and the operating speed of the actuator. Generally, from the viewpoint of protecting the rolling mill, upper limits are set for the control amount and the operating speed of the actuator. When the meandering control is started after the tail end of the rolled material has passed through the rolling mill in front of the rolling mill to be controlled, the maximum control amount in the leveling control becomes small. For this reason, for example, if the rolled material has already meandered significantly by the time the tail end of the rolled material passes through the rolling mill in front of the rolling mill to be controlled, even if the maximum control is performed, the control amount will not be sufficient. This may be insufficient and troubles may occur.

Therefore, in order to stably control the meandering of the rolled material and to allow the rolled material to pass through the center of the rolling mill as much as possible, it is necessary to set the timing of starting control and the amount of control for the rolling mill that is to be controlled. Must be set appropriately.
Therefore, the present invention was made to solve this conventional problem, and its purpose is to improve the quality of rolled material rolled in a finishing rolling facility equipped with N rolling mills (N is a natural number of 4 or more). When controlling meandering, the control start timing and control amount are appropriately set for the rolling mill to be controlled, so that the meandering of the rolled material can be stably controlled, and the rolled material can be controlled as much as possible by the rolling mill. An object of the present invention is to provide a leveling control method in hot rolling, a leveling control device, hot rolling equipment, and a method for manufacturing a hot rolled steel strip, which can pass the sheet through the center of the hot rolled steel strip.

In order to solve the above problems, a leveling control method in hot rolling according to one aspect of the present invention provides a leveling control method for a rolled material rolled in a finishing rolling facility equipped with N rolling mills (N is a natural number of 4 or more). A leveling control method in hot rolling for controlling meandering, wherein after the tail end of the rolled material passes through the n-th (any one from 1 to N-3) rolling mill from the beginning, the n-th rolling a first leveling correction amount for the n+3rd and subsequent rolling mills to be controlled based on the meandering amount detected by the first meandering amount detection device installed between the rolling mill and the n+1th rolling mill; 1 leveling correction amount calculation step, and a second meandering amount installed between the n+2nd rolling mill and the n+3rd rolling mill after the tail end of the rolled material passes the n+2nd rolling mill from the top. a second leveling correction amount calculation step of calculating a second leveling correction amount in the (n+3)th and subsequent rolling mills to be controlled based on the meandering amount detected by the detection device; In the first control section from passing through the first meandering amount detection device to the n+2th rolling mill, the leveling correction of the first leveling correction amount calculated in the first leveling correction amount calculation step is applied to the rolled material. In a second control section from when the tail end of passes through the n+2-th rolling mill to the n+3-th and subsequent rolling mills to be controlled, the second leveling correction amount is calculated in the first leveling correction amount. The gist includes a leveling control step of controlling the leveling of the rolling mill to be controlled so as to perform a leveling correction of the leveling correction amount added to the second leveling correction amount calculated in the step.

Further, a leveling control device for hot rolling according to another aspect of the present invention provides a leveling control device for controlling meandering of a rolled material rolled in a finishing rolling facility equipped with N rolling mills (N is a natural number of 4 or more). A leveling control device for inter-rolling, wherein after the tail end of the rolled material passes through the n-th (any one from 1 to N-3) rolling mill from the top, the leveling control device A first leveling correction amount calculation that calculates a first leveling correction amount in the (n+3)th and subsequent rolling mills to be controlled based on the meandering amount detected by a first meandering amount detection device installed between the rolling mill and the rolling mill. After the tail end of the rolled material passes through the n+2nd rolling mill from the beginning, it is detected by a second meandering amount detection device installed between the n+2nd rolling mill and the n+3rd rolling mill. a second leveling correction amount calculation unit that calculates a second leveling correction amount in the rolling mills to be controlled from the n+3rd onwards based on the meandering amount; In a first control section from passing through the device to reaching the n+2th rolling mill, the tail end of the rolled material adjusts the leveling correction of the first leveling correction amount calculated by the first leveling correction amount calculating section. In a second control section from passing through the n+2-th rolling mill to reaching the n+3-th and subsequent rolling mills to be controlled, the first leveling correction amount is added to the second leveling correction amount calculation unit. The present invention further comprises a leveling control section that controls the leveling of the rolling mill to be controlled so as to perform a leveling correction of a leveling correction amount including a leveling correction amount of 2 leveling correction amounts.

Further, a hot rolling facility according to another aspect of the present invention is provided with the above-mentioned leveling control device.
Further, a method for manufacturing a hot rolled steel strip according to another aspect of the present invention includes a finish rolling step of finish rolling the rolled material by controlling meandering of the rolled material using the leveling control method described above. This is the summary.

According to the leveling control method in hot rolling, the leveling control device, the hot rolling equipment, and the manufacturing method of hot rolled steel strip according to the present invention, N groups (N is a natural number of 4 or more) of rolling mills are provided. When controlling the meandering of rolled material rolled in finishing rolling equipment, the timing of starting control and its control amount are appropriately set for the rolling mill to be controlled, and the meandering of the rolled material is stably controlled. It is possible to provide a leveling control method in hot rolling, a leveling control device, hot rolling equipment, and a method for manufacturing a hot rolled steel strip, which can pass the rolled material through the center of the rolling mill as much as possible.

1 is a schematic configuration diagram of a hot rolling facility equipped with a leveling control device according to an embodiment of the present invention. 2 is a flowchart for explaining the flow of processing of the leveling control device shown in FIG. 1. FIG. FIG. 2 is a diagram showing how a meandering amount prediction model is generated by the meandering amount prediction model generation unit of the leveling control device shown in FIG. 1; It is a figure which shows the processing flow of the meandering amount prediction model which is a neural network model. FIG. 2 is a diagram for explaining leveling control in a rolling mill that is a control target that performs leveling correction by the leveling control device shown in FIG. 1. FIG. FIG. 1 is a schematic configuration diagram of a finishing rolling facility equipped with a leveling control device according to a reference example. In the finishing rolling equipment shown in FIG. 6, the amount of meandering between the fourth rolling mill F4 from the beginning and the fifth rolling mill F5, and the amount of meandering between the fifth rolling mill F5 from the beginning and the sixth rolling mill F6. It is a graph showing the relationship between. In the finishing rolling equipment shown in FIG. 6, the amount of meandering between the fifth rolling mill F5 from the beginning and the sixth rolling mill F6, and the amount of meandering between the sixth rolling mill F6 from the beginning and the seventh rolling mill F7. It is a graph showing the relationship between.

Embodiments of the present invention will be described below with reference to the drawings. The embodiments shown below illustrate devices and methods for embodying the technical idea of the present invention. It is not limited to the embodiments described below.
Furthermore, the drawings are schematic. Therefore, it should be noted that the relationships, ratios, etc. between thickness and planar dimensions are different from those in reality, and the drawings also include portions where the relationships and ratios of dimensions are different.

FIG. 1 shows a schematic configuration of a hot rolling facility equipped with a leveling control device according to an embodiment of the present invention.
The hot rolling equipment 1 shown in FIG. 1 includes a heating furnace 2 that heats a slab (rolled material) S to a predetermined temperature, and a rough rolling of the slab (rolled material) S heated in the heating furnace 2 to a predetermined thickness. It is equipped with a rough rolling mill 3 for rolling sheet bars (rolled materials) S, and a finishing rolling facility 4 for finishing rolling the sheet bars (rolled materials) S to a predetermined thickness. The rough rolling mill 3 includes M groups (M is a natural number of 2 or more) of rough rolling stands R1 to RM.

The hot rolling equipment 1 also includes a runout table 5 that cools the finish-rolled hot rolled steel strip (rolled material) S, and a winder that winds the cooled hot rolled steel strip (rolled material) S into a coil shape. It is equipped with machine 6.
Here, the finish rolling equipment 4 includes N rolling mills F1 to FN (N is a natural number of 4 or more), and finish rolls the sheet bar (rolled material) S to a predetermined thickness by tandem rolling. Each of the rolling mills F1 to FN is equipped with a leveling device 7 (only the leveling device 7 installed in the rolling mill FN is shown) that adjusts the amount of rolling on the operating side and the driving side. The rolled material S travels (is conveyed) in the direction shown by the arrow in FIG. The drive side of each of the rolling mills F1 to FN is the side to which the drive motor for the rolling rolls is attached, and the work side is the opposite side to the drive side.

Further, the finishing rolling equipment 4 is provided with a leveling control device 10 that controls meandering of the rolled material S. The leveling control device 10 is configured so that the tail end of the traveling rolled material S passes through the first meandering amount detection device 13, which will be described later, after being installed between the n-th rolling mill Fn and the n+1-th rolling mill Fn+1 from the top. The first control section A passes through the n+2nd rolling mill Fn+2 from the head, and the tail end of the rolled material S passes through the n+2nd rolling mill Fn+2 from the head and then passes through the n+3rd rolling mill Fn+3 to be controlled. In the second control section B up to, the meandering of the rolled material S is controlled by "meandering control using a meandering meter" in the rolling mill Fn+3 to be controlled.

In the present embodiment, "meandering control using a meandering meter" refers to the amount of leveling at rolling mill Fn+3 to be controlled (operation at rolling mill Fn+3) located immediately downstream of the position where the second meandering amount detection device 16 is installed. As shown in FIG. 5, the roll opening difference Lv, which is the difference in opening between the roll gaps on the side and the drive side, is determined between the rolling mill Fn where the tail end of the rolled material S is the nth one from the top and the rolling mill where the n+1th rolling mill is the n+1th rolling mill. In the first control section A, which passes through the first meandering amount detection device 13 installed between Fn+1 and the n+2 rolling mill Fn+2 from the beginning, the first meandering is performed with respect to the preset leveling amount LvL. The tail end of the rolled material S is corrected by the first leveling correction amount ΔLv1 or the first leveling correction correction amount ΔLv1' which is proportional to the meandering amount δ1 detected by the amount detection device 13, and the tail end of the rolled material S is moved to the n+2th rolling mill Fn+2 from the top. In the second control section B from passing through to passing through the n+3rd rolling mill Fn+3 to be controlled, the above-mentioned first leveling correction amount ΔLv1 or first leveling correction correction is applied to the preset leveling amount LvL. The leveling correction amount is corrected by adding a second leveling correction amount ΔLv2 or a second leveling correction correction amount ΔLv2′ which is proportional to the meandering amount δ2 detected by the second meandering amount detection device 16 to the amount ΔLv1′.

If meandering of the rolled material S occurs on the operating side, the leveling amount Lv is corrected so that the operating side is closed (to the "-" side), and if meandering of the rolled material S occurs on the driving side, the driving side closes. The leveling amount Lv is corrected (toward the "+" side) as follows. In addition, during the period from when the tail end of the rolled material S passes through the first rolling mill F1 from the beginning until it passes through the Nth rolling mill FN, excluding the first control section A and the second control section B described above, In other words, the leveling amount Lv in the rolling mill Fn+3 to be controlled is controlled to a preset leveling amount (lock-on value) LvL.

The leveling amount Lv is the opening difference between the roll gap on the work (OP) side and the roll gap on the drive (DR) side of the rolling mills F1 to FN. When the roll gap between the upper and lower work rolls is Lv_0p, and the roll gap between the upper and lower work rolls on the driving (DR) side of the rolling mills F1 to FN is Lv_dr, it is defined as Lv=Lv_0p−Lv_dr.

In the leveling control device 10 according to the present embodiment, the leveling amount Lv at the rolling mill Fn+3 to be controlled is set so that the tail end of the rolled material S is between the n-th rolling mill Fn from the top and the n+1-th rolling mill Fn+1. In the first control section A, which passes through the first meandering amount detection device 13 installed at , and passes through the n+2-th rolling mill Fn+2 from the beginning, the first meandering amount detection device 13 is determined with respect to the preset leveling amount LvL. Correct by the first leveling correction amount ΔLv1 or the first leveling correction correction amount ΔLv1' which is proportional to the meandering amount δ1 detected in , and control after the tail end of the rolled material S passes through the n+2nd rolling mill Fn+2 from the top. In the second control section B until passing through the target n+3-th rolling mill Fn+3, the preset leveling amount LvL is changed to the above-mentioned first leveling correction amount ΔLv1 or first leveling correction correction amount ΔLv1'. The reason why the leveling correction amount is corrected by adding the second leveling correction amount ΔLv2 or the second leveling correction correction amount ΔLv2' which is proportional to the meandering amount δ2 detected by the second meandering amount detection device 16 will be described later.

The leveling control device 10 will be explained in detail below.
The leveling control device 10 includes a first meandering amount detection device 13, a second meandering amount detection device 16, a first leveling correction amount calculation section 17, a second leveling correction amount calculation section 18, a meandering amount prediction model generation section 19, and a meandering amount It includes a prediction section 20, a determination section 21, a leveling correction amount correction section 22, and a leveling control section 23.

The first meandering amount detection device 13 is installed between the n-th rolling mill Fn (n is any natural number from 1 to N-3) from the beginning and the n+1-th rolling mill Fn+1, and the first imaging device 11 and a first meandering amount calculation unit 12, which detects the meandering amount δ1 of the rolled material S after the tail end of the rolled material S has passed through the n-th rolling mill Fn. The first imaging device 11 is configured with a line sensor camera or an area sensor camera, and images the surface of the rolling material S that is traveling. Further, the first meandering amount calculation unit 12 detects the positions of both widthwise ends (driving side and working side ends) of the rolled material S based on the captured image obtained by the first imaging device 11, and The position of the center in the width direction of the rolled material S is calculated from the detected positions of both ends of the rolled material S in the width direction, and the calculated center in the width direction of the rolled material S is calculated from the center in the width direction of each rolling mill F1 to FN. The distance to the position is calculated as the meandering amount δ1 of the rolled material S.

Further, the second meandering amount detection device 16 is installed between the n+2-th rolling mill Fn+2 and the n+3-th rolling mill Fn+3 from the top, and includes a second imaging device 14 and a second meandering amount calculation unit 15. , the tail end of the rolled material S detects the meandering amount δ2 of the rolled material S after passing through the n+2-th rolling mill Fn+2. Like the first imaging device 11, the second imaging device 14 is configured with a line sensor camera or an area sensor camera, and images the surface of the rolling material S as it travels. Further, the second meandering amount calculation unit 15 detects the positions of both widthwise ends (driving side and working side ends) of the rolled material S based on the captured image obtained by the second imaging device 14, and The position of the center in the width direction of the rolled material S is calculated from the detected positions of both ends of the rolled material S in the width direction, and the calculated center in the width direction of the rolled material S is calculated from the center in the width direction of each rolling mill F1 to FN. The distance to the position is calculated as the meandering amount δ2 of the rolled material S.

Also, a first leveling correction amount calculation section 17 , a second leveling correction amount calculation section 18 , a meandering amount prediction model generation section 19 , a meandering amount prediction section 20 , a determination section 21 , a leveling correction amount correction section 22 , and a leveling control section 23 Each of these is a computer system having an arithmetic processing function, and the first leveling correction amount calculation unit 17, the second leveling correction amount calculation unit 18, and the meandering amount are calculated by instructions from various dedicated computer programs stored in advance in the hardware. Each function of the predictive model generation unit 19, meandering amount prediction unit 20, determination unit 21, leveling correction amount correction unit 22, and leveling control unit 23 (Steps S2, Steps S4 to Step S10, which will be described later) is executed on software. It has become.

The first leveling correction amount calculation unit 17 calculates the first leveling correction amount ΔLv1 at the rolling mill Fn+3, which is the n+3rd control target, based on the meandering amount δ1 detected by the first meandering amount detection device 13.
Here, the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled is calculated by the following equation (1) in relation to the meandering amount δ1 detected by the first meandering amount detection device 13.
ΔLv1=α・δ1...(1)
α is a control gain, which is determined in advance in consideration of the plate thickness and plate width on the inlet and outlet sides of the n-th rolling mill Fn, and the steel type of the rolled material S.

Further, the second leveling correction amount calculation unit 18 calculates a second leveling correction amount ΔLv2 at the rolling mill Fn+3, which is the n+3rd control target, based on the meandering amount δ2 detected by the second meandering amount detection device 16. .
Here, the second leveling correction amount ΔLv2 in the rolling mill Fn+3 to be controlled is calculated by the following equation (2) in relation to the meandering amount δ2 detected by the second meandering amount detection device 16.
ΔLv2=β・δ2…(2)
β is a control gain, which is determined in advance in consideration of the plate thickness and plate width on the inlet and outlet sides of the n+2-th rolling mill Fn+2, and the steel type of the rolled material S.

Further, as shown in FIG. 3, the meandering amount prediction model generation unit 19 generates information regarding the size of the past rolled material S, information regarding the temperature of the past rolled material S, and information regarding the past work rolls of the finishing rolling equipment 4. , the actual first leveling correction amount based on the meandering amount detected by the first meandering amount detection device 13 in the past controlled rolling mill Fn+3, and the second meandering amount in the past controlled rolling mill Fn+3. The actual second leveling correction amount based on the meandering amount detected by the detection device 16 is input data, and the actual meandering amount of the tail end of the past rolled material S in the rear rolling mill FN in the finishing rolling equipment 4 is calculated based on the input data. A meandering amount prediction model 190 is generated by performing machine learning on a plurality of pieces of learning data using the output data as output data.

Here, "information regarding the size of the rolled material S" includes the dimensions of the product (thickness, width, length), the dimensions of the slab extracted from the heating furnace 2 (thickness, width, length), and The amount of camber at the leading end and tail end of the rolled material S after rough rolling is illustrated. In addition, "information regarding the temperature of the rolled material S" includes the temperature of the slab at the time of extraction in the heating furnace (average value in the width direction, temperature at the center in the width direction, temperature at the edge in the width direction), The temperature of the sheet bar after completion (average value in the board width direction, temperature at the center in the board width direction, temperature at the ends in the board width direction) is exemplified. Furthermore, "information regarding the work rolls of the finishing rolling equipment 4" includes the number of rolling rolls after changing the work rolls in each of F1 to FN, the type of work roll in each of F1 to FN, and the replacement of work rolls in each of F1 to FN. The subsequent rolling tonnage and mill rigidity difference in each of F1 to FN are exemplified.

In addition, in the case where the finishing rolling equipment 4 has N (N is a natural number of 4 or more) rolling mills F1 to FN, the "later rolling mill" for which the meandering amount of the tail end of the rolled material S is predicted. It means at least one rolling mill after the N/2th rolling mill counted sequentially from the head in the conveyance direction of the material S. In this embodiment, the Nth and final rolling mill FN from the top is a "later rolling mill" in which the meandering amount of the tail end of the rolled material S is predicted.
Here, the meandering amount of the rolled material S refers to the distance from the center of each of the rolling mills F1 to FN in the width direction (the same direction as the width direction of the rolled material S) to the center of the rolled material S in the width direction. The meandering amount of the tail end of the rolled material S is from the center of each rolling mill F1 to FN in the width direction (the same direction as the width direction of the rolled material S) to the center of the tail end of the rolled material S in the width direction. is the distance.

Note that a plurality of learning data (information regarding the size of the past rolled material S, information regarding the temperature of the past rolling material S, information regarding the past work roll of the finishing rolling equipment 4) read into the meandering amount prediction model generation unit 19 , the actual first leveling correction amount based on the meandering amount detected by the first meandering amount detection device 13 in the past controlled rolling mill Fn+3, and the second meandering amount detection in the past controlled rolling mill Fn+3. The actual second leveling correction amount based on the meandering amount detected by the device 16 and the actual meandering amount of the tail end of the past rolled material S in the rear rolling mill FN in the finishing rolling facility 4 are calculated from the host computer 24. It is input to the quantity prediction model generation section 19.

In this embodiment, since a neural network is employed as a machine learning method, a neural network model is generated as the meandering amount prediction model 190. That is, the meandering amount prediction model generation unit 19 generates input performance data (information regarding the size of the past rolled material S, information regarding the temperature of the past rolled material S, information regarding the past work roll of the finishing rolling equipment 4) in the learning data. information, the actual first leveling correction amount based on the meandering amount detected by the first meandering amount detection device 13 in the past control target rolling mill Fn+3, and the second meandering in the past control target rolling mill Fn+3. (Actual second leveling correction amount based on the meandering amount detected by the amount detection device 16) and output performance data (Actual meandering amount of the tail end of the past rolled material S in the rear rolling mill FN in the finishing rolling facility 4) A neural network model is created as a meandering amount prediction model 190 that connects. A neural network model is expressed, for example, by a functional expression.

The meandering amount prediction unit 20 also adds information regarding the size of the rolled material S in the current rolling pass and information regarding the temperature of the rolled material S in the current rolling pass to the meandering amount prediction model 190 generated by the meandering amount prediction model generation unit 19. information, information regarding the work roll of the finishing rolling equipment 4 in the current rolling pass, the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled calculated by the first leveling correction amount calculation unit 17, and the second leveling correction amount calculation The second leveling correction amount ΔLv2 of the rolling mill Fn+3 to be controlled, calculated in section 18, is input to perform a process of predicting the meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN.
Here, among the information regarding the size of the rolled material S in the current rolling pass that is input to the meandering amount prediction model 190, the dimensions of the product (thickness, width, length) and the dimensions of the slab extracted from the heating furnace 2 ( The information (thickness, width, length) is read into the meandering amount prediction unit 20 from the host computer 24.

In addition, among the information regarding the size of the rolled material S in the current rolling pass that is input to the meandering amount prediction model 190, the amount of camber at the tip and tail end of the rolled material S after rough rolling is determined by the rough rolling mill 3 and the finishing. Information on the amount of camber (amount of lateral bending) of the leading end and tail end of the rolled material S detected by the shape detector 27 installed between the rolling equipment 4 and the rolled material S is input. The shape detector 27 includes an imaging device 25 and an image processing device 26, which are installed between the rough rolling mill 3 and the finishing rolling equipment 4. The imaging device 25 is configured with an area sensor camera, and images the surface of the rolling material S that is traveling using the area sensor camera. Then, information on the image taken by the area sensor camera is sent to the image processing device 26, and the image processing device 26 calculates the luminance distribution at both ends of the rolled material S in the width direction based on the luminance distribution in the direction orthogonal to the traveling direction of the rolled material based on the imaged image. The camber amount of the tip and tail ends of the rolled material S is calculated based on the detected positions of both ends of the rolled material S in the width direction.

In addition, among the information regarding the temperature of the rolled material S in the current rolling pass that is input to the meandering amount prediction model 190, the temperature of the slab at the time of extraction from the heating furnace (average value in the width direction, temperature at the center in the width direction, The temperature at the edge in the width direction) is input from the host computer 24 to the meandering amount prediction unit 20, and the temperature of the sheet bar after rough rolling (average value in the width direction, temperature at the center in the width direction, edge in the width direction The temperature at the rough rolling mill 3 is inputted to the meandering amount prediction section 20 from a thermometer 28 installed on the outlet side of the rough rolling mill 3. Further, information regarding the work roll of the finishing rolling equipment 4 in the current rolling pass is read from the host computer 24 into the meandering amount prediction unit 20.

FIG. 4 shows a processing flow of the meandering amount prediction model 190, which is a neural network model.
The meandering amount prediction model 190, which is a neural network model, is a machine learning model that predicts the meandering amount of the tail end of the rolled material S in the rear rolling mill FN in the finishing rolling equipment 4. It includes an intermediate layer 192 and an output layer 193.
The input layer 191 includes information regarding the size of the rolled material S in the current rolling pass, information regarding the temperature of the rolled material S in the current rolling pass, information regarding the work roll of the finishing rolling equipment 4 in the current rolling pass, and the first leveling correction amount. The first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled, calculated by the calculation unit 17, and the second leveling correction amount in the rolling mill Fn+3 to be controlled, calculated by the second leveling correction amount calculation unit 18. Information on ΔLv2 is stored.

The intermediate layer 192 is composed of a plurality of hidden layers, and each hidden layer has a plurality of neurons arranged therein. The number of hidden layers configured in the intermediate layer 192 is not particularly limited, but empirically, if there are too many hidden layers, prediction accuracy decreases, so it is preferably five or less layers.
The output layer 193 combines the neuron information transmitted by the intermediate layer 192 and outputs it as a predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN in the final finishing rolling facility 4.

Further, the determining unit 21 determines whether the predicted meandering amount of the tail end portion of the rolled material S in the subsequent rolling mill FN predicted by the meandering amount predicting unit 20 is smaller than a predetermined threshold value. The predetermined threshold value is, for example, 30 mm, which is the average value of the difference between the width of the rolled material S and the width of the rolled material S between a pair of side guides (not shown) installed on the entry side of the finishing rolling equipment 4. It is set to a certain degree.

Further, the leveling correction amount correction unit 22 determines that the determination result of the determination unit 21 indicates that the predicted meandering amount of the tail end of the rolled material S in the rear rolling mill FN predicted by the meandering amount prediction unit 20 is equal to or greater than a predetermined threshold. In this case, the first leveling correction amount is calculated so that the predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN predicted by the meandering amount prediction unit 20 is smaller than the above-mentioned predetermined threshold value. Correct the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled calculated in section 17 and the second leveling correction amount ΔLv2 in rolling mill Fn+3 to be controlled calculated in the second leveling correction amount calculation section 18. do.

Specifically, the leveling correction amount correction unit 22 adjusts the first leveling correction amount so that when the predicted meandering amount described above is equal to or greater than a predetermined threshold, the predicted meandering amount described above becomes smaller than a predetermined threshold. The control gain α at ΔLv1=α・δ1 is corrected to calculate the first leveling correction correction amount ΔLv1′, and the control gain β at the second leveling correction amount ΔLv2=β・δ2 is corrected to calculate the second leveling correction correction. Calculate the amount ΔLv2'.

Further, the leveling control unit 23 determines that the determination result of the determination unit 21 indicates that the predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN predicted by the meandering amount prediction unit 20 is lower than the above-mentioned predetermined threshold value. is also small, as shown in FIG. In one control section A, the leveling correction of the first leveling correction amount ΔLv1 calculated by the first leveling correction amount calculation unit 17 is applied to the leveling correction of the n+3rd and subsequent rolling mills after the tail end of the rolled material S passes the n+2nd rolling mill Fn+2. In the second control section B up to the rolling mill Fn+3 to be controlled, leveling is performed using a leveling correction amount obtained by adding the second leveling correction amount ΔLv2 calculated by the second leveling correction amount calculation unit 18 to the first leveling correction amount ΔLv1. In order to carry out the correction, leveling control is performed by controlling the leveling device 7 provided in the rolling mill Fn+3 to be controlled.

In other words, the leveling control section 23 determines that the judgment result of the judgment section 21 indicates that the predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN predicted by the meandering amount prediction section 20 is less than the above-mentioned predetermined threshold value. is also small, the corrected leveling Lv is the sum of the leveling amount (lock-on value) LvL preset in the setup calculation in the first control section A and the first leveling correction amount ΔLv1 calculated by the first leveling correction amount calculation unit 17. Leveling control of the rolling mill Fn+3 to be controlled is performed, and in the second control section B, the leveling amount (lock-on value) LvL set in advance by setup calculation is changed to the first leveling correction amount ΔLv1 to the second leveling correction amount calculation unit 18 The leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of the leveling correction amounts including the second leveling correction amount ΔLv2 calculated in . Here, the leveling amount (lock-on value) LvL, which is set in advance in the setup calculation, is set to a value that maximizes the meandering effect among the median values of the wedge variations evaluated in advance.

The tracking information of the rolled material S is sent to the leveling control section 23, and the leveling control section 23 always knows the position of the tail end of the rolled material S. Then, the leveling control unit 23 controls the leveling of the rolling mill Fn+3 to be controlled using the leveling amount LvL set in advance by setup calculation until the tail end of the rolled material S passes through the first meandering amount detection device 13. , when the tail end of the rolled material S is in the first control section A, the leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv, which is the sum of the leveling amount LvL and the first leveling correction amount ΔLv1, and the rolled material S When the tail end of is in the second control section B after passing through the first control section A, the leveling amount LvL is changed to the first leveling correction amount ΔLv1, and the second leveling correction calculated by the second leveling correction amount calculation unit 18 is added. The leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of the leveling correction amounts added by the amount ΔLv2, and after the tail end of the rolled material passes through the second control section B, the leveling control is performed using the leveling amount LvL. Performs leveling control of rolling mill Fn+3.

In addition, the leveling control unit 23, in the leveling correction amount correction unit 22, calculates the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled, calculated by the first leveling correction amount calculation unit 17, and the second leveling correction amount calculation unit. When the second leveling correction amount ΔLv2 calculated in step 18 of the rolling mill Fn+3 to be controlled is corrected, in the rolling mill Fn+3 to be controlled, the first leveling correction amount calculation unit 17 in the first control section A described above The leveling correction of the calculated first leveling correction amount ΔLv1 is not performed, and the second leveling correction amount ΔLv2 calculated by the second leveling correction amount calculation unit 18 is added to the first leveling correction amount ΔLv1 in the second control section B. Do not perform leveling correction for the leveling correction amount. Instead, when the leveling correction amount correction unit 22 corrects the first leveling correction amount ΔLv1 and the second leveling correction amount ΔLv2, the leveling control unit 23 corrects the leveling correction amount correction unit 22 in the first control section A. The leveling correction of the corrected first leveling correction correction amount ΔLv1′ is performed by adding the second leveling correction correction amount ΔLv2′ corrected by the leveling correction amount correction unit 22 to the first leveling correction correction amount ΔLv1′ in the second control section B. Leveling control is performed by controlling the leveling device 7 provided in the rolling mill Fn+3 to be controlled so as to perform the leveling correction of the leveling correction amount.

In other words, the leveling control unit 23 uses the leveling correction amount correction unit 22 to calculate the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled, calculated by the first leveling correction amount calculation unit 17, and the second leveling correction amount calculation unit 18. When the second leveling correction amount ΔLv2 of the controlled rolling mill Fn+3 calculated in is corrected, the first leveling correction correction amount is added to the leveling amount (lock-on value) LvL set in advance in the setup calculation in the first control section A. Leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of ΔLv1', and in the second control section B, the first leveling correction correction amount is added to the leveling amount (lock-on value) LvL set in advance by setup calculation. The leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv, which is the sum of the leveling correction amount obtained by adding the second leveling correction correction amount ΔLv2′ to ΔLv1′.

Therefore, the leveling control unit 23 controls the leveling of the rolling mill Fn+3 to be controlled using the leveling amount LvL set in advance by setup calculation until the tail end of the rolled material S passes through the first meandering amount detection device 13. , when the tail end of the rolled material S is in the first control section A, the leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of the leveling amount LvL and the first leveling correction correction amount ΔLv1', and the rolling When the tail end of the material S passes through the first control section A and is in the second control section B, the second leveling correction amount ΔLv2' is added to the leveling amount LvL, the first leveling correction amount ΔLv1', and the second leveling correction amount ΔLv2'. The leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of the leveling correction amounts, and after the tail end of the rolled material passes through the second control section B, the leveling control of the rolling mill Fn+3 to be controlled is performed using the leveling amount LvL. Perform leveling control.
In addition, in FIG. 5, each of the first leveling correction amount ΔLv1, the second leveling correction amount ΔLv2, the first leveling correction correction amount ΔLv1', and the second leveling correction correction amount ΔLv2' is set on the operator (OP) side. An example of tightening the roll gap is shown.

Next, the flow of processing by the leveling control device 10 will be explained with reference to the flowchart shown in FIG.
First, in step S1, the first meandering amount detection device 13 detects the meandering of the rolled material S after the tail end of the rolled material S roughly rolled by the rough rolling mill 3 passes through the n-th rolling mill Fn from the top. Detect quantity δ1. (First meandering amount detection step).
Next, in step S2, the first leveling correction amount calculation unit 17 calculates the first leveling correction amount for the n+3 rolling mill Fn+3 to be controlled based on the meandering amount δ1 detected by the first meandering amount detection device 13. Calculate ΔLv1 (first leveling correction amount calculation step).
Here, the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled is calculated by the above-mentioned equation (1).

Next, in step S3, the second meandering amount detection device 16 detects the meandering amount δ2 of the rolled material S after the tail end of the rolled material S passes through the (n+2)th rolling mill Fn+2 from the top. (Second meandering amount detection step).
Next, in step S4, the second leveling correction amount calculation unit 18 calculates the second leveling correction amount for the n+3 rolling mill Fn+3 to be controlled based on the meandering amount δ2 detected by the second meandering amount detection device 16. Calculate ΔLv2 (second leveling correction amount calculation step).
The second leveling correction amount ΔLv2 in the rolling mill Fn+3 to be controlled is calculated by the above-mentioned equation (2).

Next, in step S5, the meandering amount prediction model generation unit 19 generates information regarding the size of the past rolled material S, information regarding the temperature of the past rolled material S, information regarding the past work roll of the finishing rolling equipment 4, and past information regarding the past rolled material S size. The actual first leveling correction amount based on the meandering amount detected by the first meandering amount detection device 13 in the rolling mill Fn+3 to be controlled, and the second meandering amount detection device 16 in the past rolling mill Fn+3 to be controlled. The actual second leveling correction amount based on the meandering amount detected by is input data, and the actual meandering amount of the tail end of the past rolled material S at the rear rolling mill FN in the finishing rolling equipment 4 with respect to this input data is output data. A meandering amount prediction model 190 is generated by performing machine learning on the plurality of learning data (meandering amount prediction model generation step).

Here, "information regarding the size of the rolled material S" includes the dimensions of the product (thickness, width, length), the dimensions of the slab extracted from the heating furnace 2 (thickness, width, length), and The amount of camber at the leading end and tail end of the rolled material S after rough rolling is illustrated. In addition, "information regarding the temperature of the rolled material S" includes the temperature of the slab at the time of extraction in the heating furnace (average value in the width direction, temperature at the center in the width direction, temperature at the edge in the width direction), The temperature of the sheet bar after completion (average value in the board width direction, temperature at the center in the board width direction, temperature at the ends in the board width direction) is exemplified. Furthermore, "information regarding the work rolls of the finishing rolling equipment 4" includes the number of rolling rolls after changing the work rolls in each of F1 to FN, the type of work roll in each of F1 to FN, and the replacement of work rolls in each of F1 to FN. The subsequent rolling tonnage and mill rigidity difference in each of F1 to FN are exemplified.

In addition, in the case where the finishing rolling equipment 4 has N (N is a natural number of 4 or more) rolling mills F1 to FN, the "later rolling mill" for which the meandering amount of the tail end of the rolled material S is predicted. It means at least one rolling mill after the N/2th rolling mill counted sequentially from the head in the conveyance direction of the material S. In this embodiment, the Nth and final rolling mill FN from the top is a "later rolling mill" in which the meandering amount of the tail end of the rolled material S is predicted.

Note that a plurality of learning data (information regarding the size of the past rolled material S, information regarding the temperature of the past rolling material S, information regarding the past work roll of the finishing rolling equipment 4) read into the meandering amount prediction model generation unit 19 , the actual first leveling correction amount based on the meandering amount detected by the first meandering amount detection device 13 in the past controlled rolling mill Fn+3, and the second meandering amount detection in the past controlled rolling mill Fn+3. The actual second leveling correction amount based on the meandering amount detected by the device 16 and the actual meandering amount of the tail end of the past rolled material S in the rear rolling mill FN in the finishing rolling facility 4 are calculated from the host computer 24. It is input to the quantity prediction model generation section 19.

Next, in step S6, the meandering amount prediction unit 20 adds information regarding the size of the rolled material S in the current rolling pass and information regarding the temperature of the rolled material S in the current rolling pass to the meandering amount prediction model 190 generated in step S5. , information regarding the work roll of the finishing rolling equipment 4 in the current rolling pass, the first leveling correction amount ΔLv1 of the rolling mill Fn+3 to be controlled calculated in step S2, and the rolling mill Fn+3 to be controlled calculated in step S4. The second leveling correction amount ΔLv2 is inputted to perform a process of predicting the meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN (meandering amount prediction step).

Here, among the information regarding the size of the rolled material S in the current rolling pass that is input to the meandering amount prediction model 190, the dimensions of the product (thickness, width, length) and the dimensions of the slab extracted from the heating furnace 2 ( The information (thickness, width, length) is read into the meandering amount prediction unit 20 from the host computer 24.

In addition, among the information regarding the size of the rolled material S in the current rolling pass that is input to the meandering amount prediction model 190, the amount of camber at the tip and tail end of the rolled material S after rough rolling is determined by the rough rolling mill 3 and the finishing. Information on the amount of camber (amount of lateral bending) of the leading end and tail end of the rolled material S detected by the shape detector 27 installed between the rolling equipment 4 and the rolled material S is input. In addition, among the information regarding the temperature of the rolled material S in the current rolling pass that is input to the meandering amount prediction model 190, the temperature of the slab at the time of extraction from the heating furnace (average value in the width direction, temperature at the center in the width direction, The temperature at the edge in the width direction) is input from the host computer 24 to the meandering amount prediction unit 20, and the temperature of the sheet bar after rough rolling (average value in the width direction, temperature at the center in the width direction, edge in the width direction The temperature at the rough rolling mill 3 is inputted to the meandering amount prediction section 20 from a thermometer 28 installed on the outlet side of the rough rolling mill 3. Further, information regarding the work roll of the finishing rolling equipment 4 in the current rolling pass is read from the host computer 24 into the meandering amount prediction unit 20.

Next, in step S7, the determination unit 21 determines whether the predicted meandering amount of the tail end of the rolled material S in the rear rolling mill FN predicted in step S6 is smaller than a predetermined threshold (determination step ). As mentioned above, the predetermined threshold value is, for example, the difference between the widthwise distance of the rolled material S and the width of the rolled material S between a pair of side guides (not shown) installed on the entry side of the finishing rolling equipment 4. It is set to an average value of about 30 mm.
If the determination result in step S7 is YES, the process moves to step S8, and if the determination result in step S7 is NO, the process moves to step S9.

In step S8, the leveling control unit 23 determines that the determination result of the determination unit 21 indicates that the predicted meandering amount of the tail end of the rolled material S in the rear rolling mill FN predicted by the meandering amount prediction unit 20 is the above-mentioned predetermined amount. Assuming that the tail end of the rolled material S is smaller than the threshold value, the first leveling correction amount calculation step ( The leveling correction of the first leveling correction amount ΔLv1 calculated in step S2) is applied until the tail end of the rolled material S passes through the n+2nd rolling mill Fn+2 and reaches the n+3rd and subsequent rolling mills Fn+3 to be controlled. In the second control section B, control is performed to perform a leveling correction of the leveling correction amount obtained by adding the second leveling correction amount ΔLv2 calculated in the second leveling correction amount calculation step (step S4) to the first leveling correction amount ΔLv1. The leveling device 7 provided in the target rolling mill Fn+3 is controlled to perform leveling control (leveling control step).

That is, in step S8, the leveling control unit 23 determines that the determination result of the determination unit 21 is that the predicted meandering amount of the tail end of the rolled material S in the rear rolling mill FN predicted by the meandering amount prediction unit 20 is The first leveling correction amount ΔLv1 calculated in the first leveling correction amount calculation step (step S2) is added to the leveling amount (lock-on value) LvL set in advance in the setup calculation in the first control section A as being smaller than a predetermined threshold value. Leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of The leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of the leveling correction amounts including the second leveling correction amount ΔLv2 calculated in the second leveling correction amount calculation step (step S4).

On the other hand, in step S9, the leveling correction amount correction unit 22 determines that the determination result in the determination unit 21 is the predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN predicted by the meandering amount prediction unit 20. is greater than or equal to the predetermined threshold, and the predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN predicted in step S6 was calculated in step S2 so that it is smaller than the predetermined threshold. The first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled and the second leveling correction amount ΔLv2 in the rolling mill Fn+3 to be controlled calculated in step S4 are corrected (leveling correction amount correction step).

Specifically, the leveling correction amount correction unit 22 adjusts the first leveling correction amount so that when the predicted meandering amount described above is equal to or greater than a predetermined threshold, the predicted meandering amount described above becomes smaller than a predetermined threshold. The control gain α at ΔLv1=α・δ1 is corrected to calculate the first leveling correction correction amount ΔLv1′, and the control gain β at the second leveling correction amount ΔLv2=β・δ2 is corrected to calculate the second leveling correction correction. Calculate the amount ΔLv2'.

Then, in step S10, the leveling control unit 23 makes the first leveling correction amount ΔLv1 and the second leveling correction in the rolling mill Fn+3 to be controlled calculated in the first leveling correction amount calculation step (step S2) in step S9. Since the second leveling correction amount ΔLv2 in the rolling mill Fn+3 to be controlled calculated in the amount calculation step (step S4) has been corrected, n+2 after the tail end of the rolled material S passes the first meandering amount detection device 13 In the first control section A up to the th rolling mill Fn+2, the leveling correction of the first leveling correction amount ΔLv1 calculated in the first leveling correction amount calculation step (step S2) is applied when the tail end of the rolled material S reaches n+2. In the second control section B after passing the rolling mill Fn+2 and reaching the rolling mill Fn+3 which is the control target from the n+3rd onwards, the first leveling correction amount ΔLv1 is changed to the second leveling correction amount calculation step (step S4). The leveling correction of the leveling correction amount added to the calculated second leveling correction amount ΔLv2 is not performed. Instead, in step 10, the leveling control unit 23 controls, in the first control section A from when the tail end of the rolled material S passes the first meandering amount detection device 13 to the n+2th rolling mill Fn+2, The leveling correction of the first leveling correction correction amount ΔLv1' corrected in the leveling correction amount correction step (step S9) is applied to the n+3rd and subsequent control targets after the tail end of the rolled material S passes through the n+2nd rolling mill Fn+2. In the second control section B up to the rolling mill Fn+3, the leveling correction amount is the sum of the first leveling correction correction amount ΔLv1' and the second leveling correction correction amount ΔLv2' corrected in the leveling correction amount correction step (step S9). The leveling of the rolling mill Fn+3 to be controlled is controlled so as to perform the leveling correction (leveling control step).

That is, in step S10, the leveling control unit 23 sets the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled calculated in step S2 and the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled calculated in step S4 in step S9. 2 Since the leveling correction amount ΔLv2 has been corrected, the control target is controlled at the corrected leveling Lv that is the sum of the leveling amount (lock-on value) LvL set in advance in the setup calculation in the first control section A and the first leveling correction correction amount ΔLv1'. Leveling control of the rolling mill Fn+3 is performed, and in the second control section B, the leveling amount (lock-on value) LvL set in advance by setup calculation is changed to the first leveling correction correction amount ΔLv1' and the second leveling correction correction amount ΔLv2'. The leveling control of the rolling mill Fn+3 to be controlled is performed using the corrected leveling Lv that is the sum of the added leveling correction amounts.

Thereby, the processing by the leveling control device 10 ends.
Here, in the leveling control device 10 according to the present embodiment, the leveling amount Lv at the rolling mill Fn+3 to be controlled is set to the rolling mill Fn whose tail end of the rolled material S is the n-th rolling mill from the top and the rolling mill Fn+1 whose tail end is the n-th rolling mill Fn+1. In the first control section A, which passes through the first meandering amount detection device 13 installed between the Corrected by the first leveling correction amount ΔLv1 or the first leveling correction correction amount ΔLv1' which is proportional to the meandering amount δ1 detected by the detection device 13, the tail end of the rolled material S passes through the n+2nd rolling mill Fn+2 from the top. In the second control section B from the time of passing through the (n+3)th rolling mill Fn+3 to be controlled, the above-mentioned first leveling correction amount ΔLv1 or first leveling correction correction amount is applied to the preset leveling amount LvL. The reason why the leveling correction amount is corrected by adding the second leveling correction amount ΔLv2 or the second leveling correction correction amount ΔLv2′ which is proportional to the meandering amount δ2 detected by the second meandering amount detection device 16 to ΔLv1′ will be explained.

FIG. 6 shows a schematic configuration of a finishing rolling facility 4 equipped with a leveling control device 100 according to a reference example.
In FIG. 6, the finishing rolling equipment 4 includes seven rolling mills F1 to F7. Further, the finishing rolling equipment 4 is provided with a leveling control device 100 that controls meandering of the rolled material S. The leveling control device 100 controls a rolling mill to be controlled in a control section B' from when the tail end of the traveling rolled material S passes through the sixth rolling mill F6 from the beginning until it passes through the seventh rolling mill F7. At F7, the meandering of the rolled material S is controlled by "meandering control using a meandering meter".

Regarding the leveling control device 100, the leveling control device 100 includes a meandering amount detection device 33, a leveling correction amount calculation section 34, and a leveling control section 35.
The meandering amount detection device 33 is installed between the sixth rolling mill F6 from the top and the seventh rolling mill F7 to be controlled, and includes an imaging device 31 and a meandering amount calculation unit 32, Detects the meandering amount δ of the rolled material S after passing through the sixth rolling mill F6.
Further, the leveling correction amount calculation unit 34 calculates the leveling correction amount for the rolling mill F7, which is the seventh control target, based on the meandering amount δ detected by the meandering amount detection device 33.

Then, the leveling control section 35 causes the leveling correction amount calculation section 34 to calculate the amount in the control section B' from when the tail end of the rolled material S passes through the sixth rolling mill F6 to the seventh rolling mill F7. The leveling control is performed by controlling the leveling device 7 provided in the rolling mill F7 to be controlled so as to perform the leveling correction of the leveling correction amount.

On the other hand, in the finishing rolling equipment 4 shown in FIG. 6, a meandering amount detection device (not shown) is installed between the fourth rolling mill F4 from the top and the fifth rolling mill F5 to A meandering amount detection device (not shown) is installed between the rolling mill F5 and the rolling mill F6 to detect the meandering amount between the rolling mill F4 and the rolling mill F5 after the part passes through the rolling mill F4. After the tail end of the rolled material S passes through the rolling mill F5, the amount of meandering between the rolling mill F5 and the rolling mill F6 is detected, and the amount of meandering between the rolling mill F4 and the rolling mill F5 and the amount of meandering between the rolling mill F5 and the rolling mill are detected. The relationship with the meandering amount between F6 was investigated. The results are shown in FIG. FIG. 7 shows the meandering amount at the time when the tail end of the rolled material S passes through the meandering amount detection device installed between rolling mill F4 and rolling mill F5, and the meandering amount at rolling mill F5 and rolling mill F6. The relationship between the amount of meandering and the amount of meandering at the time when the tail end of the rolled material S passes through the amount of meandering detection device installed between them is shown.

In addition, the meandering amount between rolling mill F5 and rolling mill F6 after the tail end of the rolled material S passes through the rolling mill F5, and the rolling distance after the tail end of the rolled material S passes through the rolling mill F6 as described above. The relationship between the meandering amount between mill F6 and rolling mill F7 was also investigated. The results are shown in FIG. FIG. 8 shows the amount of meandering at the time when the tail end of the rolled material S passes through the meandering amount detection device installed between rolling mill F5 and rolling mill F6, and the meandering amount of rolling mill F6 and rolling mill F7. The relationship between the meandering amount and the meandering amount at the time when the tail end of the rolled material S passes through the meandering amount detection device 33 installed between the two is shown.

As can be seen from FIGS. 7 and 8, when the amount of meandering between rolling mill F4 and rolling mill F5 is large, the amount of meandering between rolling mill F5 and rolling mill F6 becomes large, and accordingly, rolling mill F6 and rolling mill It can be seen that the amount of meandering between aircraft F7 has also increased. In other words, it can be seen that if the amount of meandering is large at the front stage of the rolling mill, the amount of meandering increases as the rolling mill progresses to the later stages.
Under this situation, in the leveling control device 100 according to the reference example, after the tail end of the traveling rolled material S passes through the sixth rolling mill F6 from the beginning, it is moved to the seventh rolling mill F7 to be controlled. Leveling control is starting. In this case, the meandering amount of the rolled material S may not be reduced due to insufficient control amount.

Therefore, in the leveling control device 10 according to the present embodiment, the leveling amount Lv in the rolling mill Fn+3 to be controlled is set so that the tail end of the rolled material S at the stage where the leveling control start time is advanced is the n-th point from the top. In the first control section A from passing through the first meandering amount detection device 13 installed between the rolling mill Fn and the n+1th rolling mill Fn+1 to passing through the n+2nd rolling mill Fn+2 from the beginning, the meandering amount is set in advance. The leveling amount LvL is corrected by the first leveling correction amount ΔLv1 or the first leveling correction correction amount ΔLv1' which is proportional to the meandering amount δ1 detected by the first meandering amount detection device 13, and the leveling start time is changed from the normal leveling amount LvL. In the second control section B from when the tail end of the rolled material S passes through the n+2-th rolling mill Fn+2 until it passes through the n+3-th rolling mill Fn+3, the above-mentioned leveling amount LvL is Leveling in which a second leveling correction amount ΔLv2 or a second leveling correction amount ΔLv2' proportional to the meandering amount δ2 detected by the second meandering amount detection device 16 is added to the first leveling correction amount ΔLv1 or the first leveling correction correction amount ΔLv1'. I am trying to correct the amount of correction. In the leveling control device 10 according to the present embodiment, the leveling start time is a second control period from when the tail end of the rolled material S passes through the n+2-th rolling mill Fn+2 to when it exits the n+3-th rolling mill Fn+3. In B, since the leveling control amount can be small, the problem of not being able to reduce the meandering amount of the rolled material S due to insufficient control amount can be solved.

As described above, according to the leveling control device 10 and the leveling control method according to the present embodiment, the tail end of the rolled material S passes through the nth (any one from 1 to N-3) rolling mill Fn from the beginning. After that, based on the meandering amount δ1 detected by the first meandering amount detection device 13 installed between the nth rolling mill Fn and the n+1th rolling mill Fn+1, the n+3th rolling mill Fn+3 to be controlled is The first leveling correction amount calculation unit 17 (first leveling correction amount calculation step: step S2) calculates the first leveling correction amount ΔLv1 at After passing, the n+3rd and subsequent rolling mills become the control targets based on the meandering amount δ2 detected by the second meandering amount detection device 16 installed between the n+2nd rolling mill Fn+2 and the n+3rd rolling mill Fn+3. A second leveling correction amount calculation unit 18 (second leveling correction amount calculation step: step S4) that calculates the second leveling correction amount ΔLv2 in the rolling mill, and a first meandering amount detection device 13 in which the tail end of the rolled material S is The first leveling correction amount ΔLv1 calculated by the first leveling correction amount calculation unit 17 (first leveling correction amount calculation step: step S2) in the first control section A from passing through to the n+2th rolling mill Fn+2. The leveling correction is performed by the first leveling correction amount in the second control section B from when the tail end of the rolled material S passes through the n+2 rolling mill Fn+2 to the rolling mill Fn+3 which is the control target from the n+3rd onwards. It becomes a control target so that the leveling correction is performed by adding the second leveling correction amount ΔLv2 calculated by the second leveling correction amount calculation unit 18 (second leveling correction amount calculation step: step S4) to ΔLv1. It includes a leveling control section 23 (leveling control steps: step S8, step S10) that controls leveling of the rolling mill Fn+3.

As a result, when controlling the meandering of the rolled material S rolled in the finishing rolling equipment 4 equipped with N rolling mills F1 to FN (N is a natural number of 4 or more), the rolling mill Fn+3 to be controlled is controlled. By appropriately setting the control start timing and its control amount, it is possible to stably control the meandering of the rolled material S and to allow the rolled material S to pass through the center of the rolling mills F1 to FN as much as possible.

Further, according to the leveling control device 10 and the leveling control method according to the present embodiment, information regarding the size of the past rolled material S, information regarding the temperature of the past rolled material S, and information regarding the past work rolls of the finishing rolling equipment 4. information, the actual first leveling correction amount based on the meandering amount detected by the first meandering amount detection device 13 in the past control target rolling mill Fn+3, and the second meandering in the past control target rolling mill Fn+3. The actual second leveling correction amount based on the meandering amount detected by the amount detection device 16 is input data, and the actual meandering of the tail end of the past rolled material S at the rear rolling mill FN in the finishing rolling equipment 4 is calculated based on the input data. A meandering amount prediction model generation unit 19 (meandering amount prediction model generation step: step S5) is provided which generates a meandering amount prediction model 190 by performing machine learning on a plurality of learning data whose amounts are used as output data.

According to the leveling control device 10 and the leveling control method according to the present embodiment, the meandering amount prediction model 190 generated by the meandering amount prediction model generation unit 19 (meandering amount prediction model generation step: step S5) is Information regarding the size of the rolled material S in the rolling pass, information regarding the temperature of the rolled material S in the current rolling pass, information regarding the work roll of the finishing rolling equipment 4 in the current rolling pass, the first leveling correction amount calculation unit 17 (first leveling The first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled calculated in the correction amount calculation step: Step S2) and the second leveling correction amount calculation unit 18 (second leveling correction amount calculation step: Step S4) A meandering amount prediction unit 20 (meandering amount Prediction step: Step S6).

As a result, in the rolling mill Fn+3 to be controlled, the first The leveling correction of the first leveling correction amount ΔLv1 calculated by the leveling correction amount calculation unit 17 (first leveling correction amount calculation step: step S2) is performed after the tail end of the rolled material S passes through the n+2th rolling mill Fn+2. In the second control section B up to the second meandering amount detection device 16, the leveling correction of the second leveling correction amount ΔLv2 calculated by the second leveling correction amount calculation unit 18 (second leveling correction amount calculation step: step S4) It is possible to predict the meandering amount of the tail end portion of the rolled material S in the subsequent rolling mill FN when performing the following steps.

Further, according to the leveling control device 10 and the leveling control method according to the present embodiment, the tail end of the rolled material S in the subsequent rolling mill FN predicted by the meandering amount prediction unit 20 (meandering amount prediction step: step S6) A determination unit 21 (determination step: step S7) is provided to determine whether the predicted meandering amount is smaller than a predetermined threshold value.

According to the leveling control device 10 and the leveling control method according to the present embodiment, the determination result in the determination unit 21 (determination step: step S7) is determined by the meandering amount prediction unit 20 (meandering amount prediction step: step S6). When the predicted meandering amount of the tail end of the rolled material S in the post-rolling mill FN is greater than or equal to a predetermined threshold, the post-rolling predicted by the meandering amount prediction unit 20 (meandering amount prediction step: step S6) Calculated by the first leveling correction amount calculation unit 17 (first leveling correction amount calculation step: step S2) so that the predicted meandering amount of the tail end of the rolled material S in the machine FN is smaller than the above-mentioned predetermined threshold value. The first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled, and the first leveling correction amount ΔLv1 in the rolling mill Fn+3 to be controlled, calculated by the second leveling correction amount calculation unit 18 (second leveling correction amount calculation step: step S4). It includes a leveling correction amount correction section 22 (leveling correction amount correction step: step S9) that corrects the second leveling correction amount ΔLv2.

As a result, when the predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN is greater than or equal to a predetermined threshold, the predicted meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN is determined. The calculated first leveling correction amount ΔLv1 and second leveling correction amount ΔLv2 can be corrected so that the amount becomes smaller than a predetermined threshold value.

Further, according to the leveling control device 10 and the leveling control method according to the present embodiment, the leveling control unit 23 (leveling control step: step S8) determines that the determination result in the determination unit 21 (determination step: step S7) is meandering. In the first control section A, when the predicted meandering amount of the tail end of the rolled material S in the rear rolling mill FN predicted by the amount prediction unit 20 (meandering amount prediction step: step S6) is smaller than a predetermined threshold value, , the leveling correction of the first leveling correction amount ΔLv1 calculated by the first leveling correction amount calculation unit 17 (first leveling correction amount calculation step: step S2) is applied to the first leveling correction amount ΔLv1 in the second control section B. The rolling mill Fn+3 to be controlled is configured to perform a leveling correction of the leveling correction amount obtained by adding the second leveling correction amount ΔLv2 calculated by the second leveling correction amount calculation unit (second leveling correction amount calculation step: step S4). Control leveling.

Further, according to the leveling control device 10 and the leveling control method according to the present embodiment, the leveling control section 23 (leveling control step: step S10) is configured to perform the leveling correction amount correction section 22 (leveling correction amount correction step: step S9). , when the first leveling correction amount ΔLv1 and the second leveling correction amount ΔLv2 are corrected, the first leveling correction amount ΔLv1 in the first control section A and the second leveling correction amount ΔLv1 in the second control section B are corrected. Instead of the leveling correction of the leveling correction amount adding the leveling correction amount ΔLv2, the first leveling correction correction amount ΔLv1 corrected by the leveling correction amount correction unit 22 (leveling correction amount correction step: step S9) in the first control section A In the second control period B, the leveling correction amount ΔLv2' corrected by the leveling correction amount correction unit 22 (leveling correction amount correction step: step S9) is added to the first leveling correction correction amount ΔLv1'. The leveling of the rolling mill Fn+3 to be controlled is controlled so as to carry out the leveling correction of the added leveling correction amount.

As a result, when controlling the meandering of the rolled material S rolled in the finishing rolling equipment 4 equipped with N rolling mills F1 to FN (N is a natural number of 4 or more), the rolling mill Fn+3 to be controlled is controlled. The amount of leveling correction in the first control section A and the second control section B becomes appropriate, and the meandering amount of the tail end of the rolled material S in the subsequent rolling mill FN can be reliably suppressed within a predetermined threshold value.

Further, the method for manufacturing a hot rolled steel strip according to the present embodiment includes a finish rolling step of finish rolling the rolled material S by controlling the meandering of the rolled material S using the leveling control method described above; The method includes a cooling step in which the rolled material S, which has become a hot rolled steel strip, is cooled using a runout table (cooling equipment), and a winding step in which the cooled hot rolled steel strip is wound into a coil shape using a winder. Thereby, the amount of meandering of the rolled material S to be finish rolled can be reduced, and the productivity and yield in hot rolling of the hot rolled steel strip can be improved.

Although the embodiments of the present invention have been described above, the present invention is not limited thereto, and various changes and improvements can be made.
For example, in the leveling control device 10 and leveling control method according to the present embodiment, the meandering amount prediction model generation section 19 (meandering amount prediction model generation step: step S5), the meandering amount prediction section 20 (meandering amount prediction step: step S6) , the determination unit 21 (determination step: step S7) and the leveling correction amount correction unit 22 (leveling correction amount correction step: step S9) are omitted, and the meandering amount is not predicted, determined, and leveling correction amount correction is performed. In the leveling control section 23 (leveling control step: step S8), in the first control section A, the first leveling correction amount ΔLv1 calculated by the first leveling correction amount calculation section 17 (first leveling correction amount calculation step: step S2) In the second control period B, the second leveling correction amount ΔLv2 calculated by the second leveling correction amount calculation unit 18 (second leveling correction amount calculation step: step S4) is added to the first leveling correction amount ΔLv1. The leveling of the rolling mill Fn+3 to be controlled may be controlled so as to perform the leveling correction of the leveling correction amount.

Further, the rolling mill to be controlled is not limited to the n+3rd rolling mill Fn+3 from the top, but may be any one or more rolling mills after the n+3rd rolling mill.
In addition, in the case where the finishing rolling equipment 4 has N (N is a natural number of 4 or more) rolling mills F1 to FN, the "later rolling mill" for which the meandering amount of the tail end of the rolled material S is predicted. This means at least one rolling mill after the N/2nd rolling mill counting sequentially from the head in the conveyance direction of the material S, and the Nth final rolling mill FN from the head is the tail end of the rolled material S. This is not limited to cases where the rolling mill is a "second rolling mill" where the amount of meandering in the section is predicted.

In addition to the first leveling correction amount ΔLv1 and the second leveling correction amount ΔLv2, in the leveling control device 10 and the leveling control method according to the present embodiment, in addition to the first leveling correction amount ΔLv1 and the second leveling correction amount ΔLv2, Based on the meandering amount detected by the meandering amount detection device installed in between, the leveling correction amount at the n+3th rolling mill Fn+3 to be controlled is calculated, and the tail end of the rolled material S is the n+1th rolling mill. Even if the leveling of the rolling mill Fn+3 to be controlled is controlled so that the leveling correction of the calculated leveling correction amount is carried out in the interval from passing through to the n+2th rolling mill Fn+2. good.

Furthermore, in the leveling control device 10 and the leveling control method according to the present embodiment, the machine learning method is a neural network, and the meandering amount prediction model 190 is a prediction model constructed by a neural network. For example, it may be a decision tree.

In FIG. 1, in order to verify the effect of the leveling control method according to the present invention, Comparative Example 1, Comparative Example 2, the present invention The amount of meandering in the rear rolling mill F7 in each case of Example 1 and Inventive Example 2 was measured.
In Comparative Example 1, after the tail end of the rolled material S passes through the sixth rolling mill F6 from the beginning, the meandering amount detection device installed between the sixth rolling mill F6 and the seventh rolling mill F7 The amount of leveling correction at the seventh rolling mill F7 to be controlled is calculated based on the meandering amount detected by , and after the tail end of the rolled material S passes through the sixth rolling mill F6, it becomes the control target. In the control section up to the seventh rolling mill F7, the leveling of the rolling mill F7 to be controlled was controlled so as to implement the leveling correction of the calculated leveling correction amount.

In Comparative Example 2, after the tail end of the rolled material S passes through the i-th (i=4, 5)-th rolling mill Fi from the beginning, the i-th rolling mill Fi and the i+1-th rolling mill Fi Based on the meandering amount detected by the meandering amount detection device installed between the In the control section from when the end passes through the i-th rolling mill Fi to the i+1-th rolling mill Fi+1, the leveling correction is performed by the calculated leveling correction amount. Leveling of rolling mill Fi+1 was controlled.

In Example 1 of the present invention, after the tail end of the rolled material S passes through the fourth rolling mill F4 from the beginning, a third rolling mill F4 is installed between the fourth rolling mill F4 and the fifth rolling mill F5. The first leveling correction amount in the seventh rolling mill F7 to be controlled is calculated based on the meandering amount detected by the meandering amount detection device 13, and the tail end of the rolled material S is the sixth rolling mill from the top. After passing through the rolling mill F6, the seventh rolling mill to be controlled is based on the meandering amount detected by the second meandering amount detection device 16 installed between the sixth rolling mill F6 and the seventh rolling mill F7. The second leveling correction amount in the rolling mill F7 is calculated, and in the first control section A from when the tail end of the rolled material S passes through the fourth rolling mill F4 to the sixth rolling mill F6, the second leveling correction amount is calculated. The leveling correction amount of one leveling correction amount is changed to the first leveling correction amount in the second control section B from when the tail end of the rolled material S passes through the sixth rolling mill F6 to the seventh rolling mill F7. The leveling of the rolling mill F7 to be controlled was controlled so as to perform the leveling correction of the leveling correction amount including the second leveling correction amount ΔLv2.

In Example 2 of the present invention, after the tail end of the rolled material S passes through the fourth rolling mill F4 from the beginning, the rolling mill F4 is installed between the fourth rolling mill F4 and the fifth rolling mill F5. The first leveling correction amount in the seventh rolling mill F7 to be controlled is calculated based on the meandering amount detected by the meandering amount detection device 13, and the tail end of the rolled material S is the sixth rolling mill from the top. After passing through the rolling mill F6, the seventh rolling mill to be controlled is based on the meandering amount detected by the second meandering amount detection device 16 installed between the sixth rolling mill F6 and the seventh rolling mill F7. The second leveling correction amount at rolling mill F7 was calculated. Further, in the second embodiment of the present invention, a meandering amount prediction model generation step (step S5), a meandering amount prediction step (step S6), a determination step (step S7), a leveling control step (step S8), a leveling correction amount correction step (Step S9), and a leveling control step (Step S10) was executed.

In Example 2 of the present invention, in the meandering amount prediction model generation step (step S5), the meandering amount prediction model 190 was generated by performing machine learning using Chainer, a known deep learning framework. Data from 30,000 operations was used as the learning data. A batch normalization method (batch size was set to 256) was used for machine learning, and the Adam method was used to set the learning rate. The input performance data of the learning data includes information about the size of past rolled material S, "product dimensions (thickness, width, length), dimensions of the slab extracted from the heating furnace 2 (thickness, width, length)" information on the temperature of the rolled material S), the amount of camber at the tip and tail ends of the rolled material S after rough rolling, and the information regarding the temperature of the rolled material S, "the temperature of the slab at the time of extraction from the heating furnace (average value in the width direction, temperature at the center, temperature at the edge in the strip width direction), and temperature of the sheet bar after rough rolling (average value in the strip width direction, temperature at the center in the strip width direction, temperature at the edge in the strip width direction). Information regarding the work rolls of the finishing rolling equipment 4: "Number of rolls rolled after changing the work rolls in each of F1 to F7, type of work roll in each of F1 to F7, tonnage rolled after changing the work rolls in each of F1 to F7" , and the mill rigidity difference in each of F1 to F7, the actual first leveling correction amount based on the meandering amount detected by the first meandering amount detection device 13 in the past controlled rolling mill F7, and the past control The actual second leveling correction amount is based on the meandering amount detected by the second meandering amount detection device 16 in the target rolling mill F7. Moreover, the output performance data of the learning data is the past actual meandering amount of the tail end of the rolled material S in the subsequent rolling mill F7 in the finishing rolling facility 4.

In Example 2 of the present invention, in the meandering amount prediction step (step S6), information regarding the size of the rolled material S in the current rolling pass is added to the meandering amount prediction model 190 generated in the meandering amount prediction model generation step (step S5). "Dimensions of the product (thickness, width, length), dimensions of the slab extracted from the heating furnace 2 (thickness, width, length), and the tip and tail ends of the rolled material S after rough rolling. camber amount", information regarding the temperature of the rolled material in the current rolling pass, "temperature of the slab at the time of extraction from the heating furnace (average value in the strip width direction, temperature at the center in the strip width direction, temperature at the edges in the strip width direction), Temperature of the sheet bar after rolling (average value in the strip width direction, temperature at the center in the strip width direction, temperature at the ends in the strip width direction)", information regarding the work rolls of the finishing rolling equipment 4 in the current rolling pass "F1 ~ The number of rolling rolls after changing the work rolls in each of F7, the type of work roll in each of F1 to F7, the rolling tonnage after changing the work rolls in each of F1 to F7, and the mill rigidity difference in each of F1 to F7. , the calculated first leveling correction amount ΔLv1 in the rolling mill F7 to be controlled and the calculated second leveling correction amount ΔLv2 in the rolling mill F7 to be controlled are input, and the rolled material in the subsequent rolling mill F7 is calculated. The amount of meandering at the tail end of S was predicted.

Furthermore, in the second embodiment of the present invention, the predetermined threshold applied in the determination step (step S7) is the distance in the width direction of the rolled material between a pair of side guides (not shown) installed on the entry side of the finishing rolling equipment 4. The width of the rolled material S was set to 30 mm, which is the average value of the difference interval between the width of the rolled material S and the width of the rolled material S.
In the latter rolling mill F7 when the leveling control of Comparative Example 1, Comparative Example 2, Invention Example 1, and Invention Example 2 was performed on 100 pieces each of rolled material S with a finished plate thickness of 4 mm or less and a plate width of 1600 mm or less. Table 1 shows the measurement results of the meandering amount.

In Table 1, absolute values were used to calculate the average value μ (mm) and standard deviation 3σ of the meandering amount of the tail end of the rolled material S in the subsequent rolling mill F7. This is because meandering x mm toward the work side and meandering x mm toward the drive side have the same risk of trouble with the aperture.
As shown in Table 1, in the case of Inventive Example 1 and Inventive Example 2, both the average value μ and standard deviation 3σ of the meandering amount of the tail end of the rolled material S in the rear rolling mill F7 are the same as in Comparative Example 1 and This was improved compared to the case of Comparative Example 2, and the effect of reducing the meandering amount of the rolled material S in the rear rolling mill F7 was confirmed.

In addition, in the case of Inventive Example 2, the average value μ and standard deviation 3σ of the meandering amount of the tail end of the rolled material S in the rear rolling mill F7 are improved compared to Inventive Example 1. , the meandering amount prediction model generation step (step S5), the meandering amount prediction step (step S6), the determination step (step S7), and the leveling correction amount correction step (step S9), the meandering amount of the rolled material S can be determined. was confirmed to be further reduced.
Furthermore, according to the method for manufacturing a hot rolled steel strip according to the present invention, the amount of meandering of the rolled material S to be finish rolled can be reduced, and the productivity and yield in hot rolling of the hot rolled steel strip can be improved. can be improved.

1 Hot rolling equipment 2 Heating furnace 3 Rough rolling mill 4 Finish rolling equipment 5 Runout table 6 Winder 7 Leveling device 10 Leveling control device 11 First imaging device 12 First meandering amount calculation unit 13 First meandering amount detection device 14 Second imaging device 15 Second meandering amount calculation section 16 Second meandering amount detection device 17 First leveling correction amount calculation section 18 Second leveling correction amount calculation section 19 Meandering amount prediction model generation section 20 Meandering amount prediction section 21 Judgment section 22 Leveling correction amount correction unit 23 Leveling control unit 24 Host computer 25 Imaging device 26 Image processing device 27 Shape detector A First control section B Second control section R1 to RM Rough rolling stand F1 to FN Rolling machine S Rolled material

Claims (14)

A leveling control method in hot rolling for controlling meandering of a rolled material rolled in a finishing rolling facility equipped with N rolling mills (N is a natural number of 4 or more),
After the tail end of the rolled material passes through the nth (any one from 1 to N-3) rolling mill from the beginning, the tail end of the rolled material passes through the nth rolling mill installed between the nth rolling mill and the n+1th rolling mill. a first leveling correction amount calculation step of calculating a first leveling correction amount in the (n+3)th and subsequent rolling mills to be controlled based on the meandering amount detected by the meandering amount detection device;
A meandering amount detected by a second meandering amount detection device installed between the n+2nd rolling mill and the n+3rd rolling mill after the tail end of the rolled material passes through the n+2nd rolling mill from the top. a second leveling correction amount calculation step of calculating a second leveling correction amount for the rolling mill to be controlled from the n+3rd onwards based on the above;
The first leveling correction calculated in the first leveling correction amount calculation step in the first control section from when the tail end of the rolled material passes the first meandering amount detection device to the n+2th rolling mill. The first leveling correction is performed in a second control section from when the tail end of the rolled material passes through the n+2-th rolling mill until reaching the n+3-th and subsequent rolling mills to be controlled. a leveling control step of controlling the leveling of the rolling mill to be controlled so as to perform a leveling correction of a leveling correction amount obtained by adding a second leveling correction amount calculated in the second leveling correction amount calculation step to the amount of the second leveling correction amount calculated in the second leveling correction amount calculation step; A leveling control method in hot rolling, comprising: Information regarding the size of the rolled material in the past, information regarding the temperature of the rolled material in the past, information regarding the work roll of the finishing rolling equipment in the past, and detection of the first meandering amount in the rolling mill to be controlled in the past. An actual first leveling correction amount based on the amount of meandering detected by the device, and an actual second leveling correction amount based on the amount of meandering detected by the second meandering amount detection device in the past rolling mill to be controlled. Meandering amount is predicted by machine learning a plurality of pieces of learning data, in which input data is input data, and output data is the actual meandering amount of the tail end of the rolled material in the past in the rear rolling mill of the finishing rolling equipment. 2. The leveling control method in hot rolling according to claim 1, further comprising the step of generating a meandering amount prediction model. The meandering amount prediction model includes information regarding the size of the rolled material in the current rolling pass, information regarding the temperature of the rolled material in the current rolling pass, information regarding the work roll of the finishing rolling equipment in the current rolling pass, and the first leveling. A first leveling correction amount in the rolling mill to be controlled, calculated in the correction amount calculation step, and a second leveling correction amount in the rolling mill to be controlled, calculated in the second leveling correction amount calculation step. 3. The leveling control method in hot rolling according to claim 2, further comprising a meandering amount prediction step of inputting and predicting the meandering amount of the tail end of the rolled material in the post-rolling mill. Claim comprising a determination step of determining whether the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted in the meandering amount prediction step is smaller than a predetermined threshold value. 3. The leveling control method in hot rolling according to 3. If the determination result in the determination step is that the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted in the meandering amount prediction step is greater than or equal to the predetermined threshold, the meandering amount prediction is performed. The control target calculated in the first leveling correction amount calculation step is set such that the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted in the step is smaller than the predetermined threshold value. It is characterized by including a leveling correction amount correction step of correcting a first leveling correction amount in the rolling mill and a second leveling correction amount in the rolling mill to be controlled, which is calculated in the second leveling correction amount calculation step. The leveling control method in hot rolling according to claim 4. In the leveling control step, if the determination result in the determination step is that the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted in the meandering amount prediction step is smaller than the predetermined threshold value. In the first control period, the leveling correction of the first leveling correction amount calculated in the first leveling correction amount calculating step is applied to the second leveling correction amount in the second control period. Controlling the leveling of the rolling mill to be controlled so as to perform a leveling correction of the leveling correction amount including the second leveling correction amount calculated in the amount calculation step, and in the leveling correction amount correction step, When the leveling correction amount and the second leveling correction amount are corrected, the leveling correction of the first leveling correction amount in the first control section and the second leveling correction amount are added to the first leveling correction amount in the second control section. In place of the leveling correction of the leveling correction amount with the addition of The leveling of the rolling mill to be controlled is controlled so as to perform a leveling correction of a leveling correction amount obtained by adding a second leveling correction correction amount corrected in the leveling correction amount correction step to the leveling correction correction amount. The leveling control method in hot rolling according to claim 5. A leveling control device in hot rolling that controls meandering of a rolled material rolled in a finishing rolling facility equipped with N rolling mills (N is a natural number of 4 or more),
After the tail end of the rolled material passes through the nth (any one from 1 to N-3) rolling mill from the beginning, the tail end of the rolled material passes through the nth rolling mill installed between the nth rolling mill and the n+1th rolling mill. a first leveling correction amount calculation unit that calculates a first leveling correction amount in the (n+3)th and subsequent rolling mills to be controlled based on the meandering amount detected by the meandering amount detection device;
A meandering amount detected by a second meandering amount detection device installed between the n+2nd rolling mill and the n+3rd rolling mill after the tail end of the rolled material passes through the n+2nd rolling mill from the top. a second leveling correction amount calculating unit that calculates a second leveling correction amount in the rolling mills to be controlled from the n+3rd onwards based on the above;
A first leveling correction calculated by the first leveling correction amount calculation unit in a first control section from when the tail end of the rolled material passes the first meandering amount detection device to the n+2th rolling mill. The first leveling correction is performed in a second control section from when the tail end of the rolled material passes through the n+2-th rolling mill until reaching the n+3-th and subsequent rolling mills to be controlled. a leveling control unit that controls leveling of the rolling mill to be controlled so as to perform a leveling correction of a leveling correction amount obtained by adding a second leveling correction amount calculated by the second leveling correction amount calculation unit to the leveling correction amount calculated by the second leveling correction amount calculation unit; A leveling control device for hot rolling, characterized by comprising: Information regarding the size of the rolled material in the past, information regarding the temperature of the rolled material in the past, information regarding the work roll of the finishing rolling equipment in the past, and detection of the first meandering amount in the rolling mill to be controlled in the past. An actual first leveling correction amount based on the amount of meandering detected by the device, and an actual second leveling correction amount based on the amount of meandering detected by the second meandering amount detection device in the past rolling mill to be controlled. Meandering amount is predicted by machine learning a plurality of pieces of learning data, in which input data is input data, and output data is the actual meandering amount of the tail end of the rolled material in the past in the rear rolling mill of the finishing rolling equipment. 8. The leveling control device for hot rolling according to claim 7, further comprising a meandering amount prediction model generating section that generates a model. The meandering amount prediction model includes information regarding the size of the rolled material in the current rolling pass, information regarding the temperature of the rolled material in the current rolling pass, information regarding the work roll of the finishing rolling equipment in the current rolling pass, and the first leveling. A first leveling correction amount in the rolling mill to be controlled, which is calculated by the correction amount calculation unit, and a second leveling correction amount in the rolling mill, which is to be controlled, which is calculated by the second leveling correction amount calculation unit. 9. The leveling control device for hot rolling according to claim 8, further comprising a meandering amount prediction unit that inputs and predicts the meandering amount of the tail end of the rolled material in the post-rolling mill. . The method is characterized by comprising a determination unit that determines whether the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted by the meandering amount prediction unit is smaller than a predetermined threshold value. The leveling control device for hot rolling according to claim 9. The meandering amount prediction is performed when the determination result in the determination unit is that the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted by the meandering amount prediction unit is equal to or greater than the predetermined threshold value. The control target is calculated by the first leveling correction amount calculation unit so that the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted by the part is smaller than the predetermined threshold value. A leveling correction amount correction unit that corrects a first leveling correction amount in the rolling mill and a second leveling correction amount in the rolling mill to be controlled calculated by the second leveling correction amount calculation unit. The leveling control device for hot rolling according to claim 10. The leveling control unit determines that the determination result in the determination unit is that the predicted meandering amount of the tail end of the rolled material in the rear rolling mill predicted by the meandering amount prediction unit is smaller than the predetermined threshold value. In the first control period, the leveling correction of the first leveling correction amount calculated by the first leveling correction amount calculation unit is applied to the second leveling correction amount in the second control period. The leveling of the rolling mill to be controlled is controlled so as to perform a leveling correction of the leveling correction amount added to the second leveling correction amount calculated by the amount calculation unit, and the leveling correction amount correction unit When the leveling correction amount and the second leveling correction amount are corrected, the leveling correction of the first leveling correction amount in the first control section and the second leveling correction amount are added to the first leveling correction amount in the second control section. In place of the leveling correction of the leveling correction amount with the addition of The leveling of the rolling mill to be controlled is controlled so as to perform a leveling correction of a leveling correction amount obtained by adding a second leveling correction correction amount corrected by the leveling correction amount correction unit to the leveling correction correction amount. The leveling control device for hot rolling according to claim 11. A hot rolling facility comprising the leveling control device according to any one of claims 7 to 12. A hot rolled steel comprising a finish rolling step of controlling the meandering of the rolled material using the leveling control method according to any one of claims 1 to 6 and finish rolling the rolled material. How to make obi.

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