Plate release prevention system

Abstract

To provide a plate release prevention system capable of predecting plate releasing of a looper to use it for preventing plate releasing.SOLUTION: This plate release prevention system comprises: a camera that images a looper provided between two rolling stands and a shape of a rolling material conveyed on the looper to generate image data; and an image processing device that determines a sign of plate releasing which results in a loss of contact between the looper and the rolling material on the basis of the image data, and outputs a prescribed first command set in accordance with a detection result to a control device that controls the two rolling stands and the looper. The image processing device compares the image data with preset determination reference to determine the sign of plate releasing.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a looper strip separation prevention system for use in a rolling system.

Background Art

[0002] Finish rolling in a steel plant is an important process for performing fine processing on a rolled material. A plurality of rolling stands for rolling the rolled material are provided in a finish rolling facility, and a looper is installed between adjacent rolling stands. The looper suppresses fluctuations in the tension of the rolled material and ensures a stable strip passing state by moving up and down while supporting the rolled material conveyed between the rolling stands from below.

[0003] In finish rolling, a phenomenon in which the rolled material suddenly separates from the looper may occur, and this phenomenon is called strip separation. If the rolled material is conveyed while being separated from the looper, there arises a problem that the rolled material becomes jammed between the rolling stands and cannot pass therethrough. If such a state is left unattended, the rolled material will accumulate between the rolling stands, which not only damages the rolled material but also may cause failure to equipment. In such a case, it is necessary to stop the rolling line, which takes a long time to restore operation.

[0004] Patent Document 1 discloses a technology in which by incorporating the rotation speed of an electric motor that drives a looper into a tension control system of the looper, stable looper height control can always be achieved even if rolling conditions fluctuate. However, since this control system strongly depends on tension, it may not function when strip separation occurs and a tensionless state is reached.

[0005] Patent Document 2 discloses a technique that incorporates multivariable looper control, which controls the looper angle and rolled material tension to target values, into the looper control system. When plate separation occurs, the controller detects the abnormality and controls the looper height and stand speed to prioritize plate passage. This technique makes it possible to return to a stable plate passage state by bringing the looper into contact with the rolled material and detecting the tension again. However, when plate separation occurs, it is difficult to obtain quantitative target values ​​for controlling the looper height and stand speed, making it difficult to control them optimally. This may lead to problems such as overtension due to outputting incorrect control values. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 5-305322 [Patent Document 2] Japanese Patent Publication No. 2006-181582 [Overview of the project] [Problems that the invention aims to solve]

[0007] Thus, with conventionally known techniques, if plate separation occurs, the tension can become fixed at zero, potentially leading to an uncontrollable situation. It is desirable to avoid this uncontrollable state by predicting plate separation before it occurs and having the rolling system take measures to prevent it.

[0008] The embodiment of the present invention aims to provide a plate separation prevention system that can predict plate separation from a looper and use that prediction to help prevent plate separation. [Means for solving the problem]

[0009] Embodiments of the present invention include a looper provided between two rolling stands, a camera that captures images of the shape of a rolled material being transported on the looper and generates image data, and an image processing device that determines, based on the image data, an indication of plate separation, where contact between the looper and the rolled material is lost, and outputs a predetermined first command set according to the detection result to a control device that controls the two rolling stands and the looper. The image processing device has a determination criterion that represents the shape of the rolled material in the state of impending plate separation, and analyzes the shape of the rolled material contained in the image data by performing image processing on the image data, and determines the indication of plate separation if the analyzed shape of the rolled material is the shape of the rolled material in the state of impending plate separation represented by the determination criterion. The shape of the rolled material in the state indicating the impending separation of the plate is such that the rolled material is in contact with the looper, and at least a portion of the rolled material between the rolling stand and the looper on the upstream side in the conveying direction of the rolled material is positioned at a height that separates it from the looper. [Effects of the Invention]

[0010] According to one embodiment, a plate separation prevention system is provided that can predict plate separation from the looper and use that prediction to help prevent plate separation. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic block diagram illustrating a looper plate separation prevention system according to an embodiment. [Figure 2] Figures 2(a) to 2(c) are schematic diagrams illustrating the relationship between the position of the looper and the position of the rolled material. [Figure 3] This is an example flowchart illustrating the operation of the plate separation prevention system according to the embodiment. [Figure 4] This is an example flowchart illustrating the operation of the plate separation prevention system according to the embodiment. [Modes for carrying out the invention]

[0012] The embodiments will be described below with reference to the drawings. Please note that the drawings are schematic or conceptual, and the relationships between the thickness and width of each part, as well as the ratios of the sizes of the parts, are not necessarily identical to those of reality. Furthermore, even when representing the same part, the dimensions and ratios may differ between drawings. In this specification and in each figure, elements similar to those described above are denoted by the same reference numerals, and detailed explanations are omitted as appropriate.

[0013] Figure 1 is a schematic block diagram illustrating a looper plate separation prevention system according to an embodiment. As shown in Figure 1, the plate separation prevention system 100 according to this embodiment includes cameras 5a and 5b and an image processing device 8. Cameras 5a and 5b capture images of the relationship between the position of the looper 3 and the position of the rolled material 4 to generate image data Da and Db, which are output to the image processing device 8. Based on the image data Da and Db, the image processing device 8 determines whether or not plate separation has occurred and whether or not there is an abnormality in the plate shape, generates processing commands according to each state, and outputs them to controllers 10 and 11.

[0014] More specifically, if the image processing device 8 determines that a board detachment has occurred, it generates a board detachment alert and outputs it to the controllers 10 and 11. If the image processing device 8 determines that there is a possibility of a board detachment occurring, it generates a board detachment prediction alert D1 and outputs it to the controllers 10 and 11. The controllers 10 and 11 have pre-configured processing programs for when they receive these alerts, and they start the processing programs to execute appropriate accident prevention measures. Appropriate accident prevention measures include, for example, emergency stopping of the line, or switching from automatic operation to manual operation.

[0015] The configuration of the plate separation prevention system 100 according to this embodiment will be described in more detail. FIG. 1 shows a rolling stand 1, a rolling stand 2, and a looper 3. In this example, the rolling stand 1 is arranged on the upstream side of a rolling line. The rolling stand 2 is arranged downstream of the rolling stand 1. The looper 3 is arranged between the two rolling stands 1 and 2. A rolled material 4 passes through the upstream rolling stand 1, passes through the looper 3, and reaches the downstream rolling stand 2.

[0016] The rolling stand 2 is driven by a motor 12 whose speed is controlled by a drive device 13. Although not illustrated in FIG. 1, the rolling mill of the rolling stand 1 is also driven by a motor whose speed is controlled by a drive device. A controller 10 is connected to the drive device 13, and the drive device 13 controls the speed of the motor 12 and the like in accordance with a speed reference DN generated by the controller 10.

[0017] The looper 3 is arranged below the rolled material 4 between the two rolling stands 1 and 2, and supports the rolled material 4 from below. The height of the looper 3 is adjusted by an actuator 14 controlled in accordance with a height reference DH generated by a controller 11. The rolled material 4 is controlled to have a predetermined tension according to the height of the looper 3.

[0018] A camera 5a is arranged on the work side of the arrangement of the rolling stands 1, 2 and the looper 3, and images the looper 3 and the rolled material 4 supported by the looper 3 from the work side. The position of the camera 5a is set such that the looper 3 and the rolled material 4 fall within an imaging range 6a of the camera 5a.

[0019] A camera 5b is arranged on the drive side of the arrangement of the rolling stands 1, 2 and the looper 3, and images the looper 3 and the rolled material 4 supported by the looper 3 from the drive side. The position of the camera 5b is set such that the looper 3 and the rolled material 4 fall within an imaging range 6b of the camera 5b.

[0020] Cameras 5a and 5b capture images of the looper 3 and rolled material 4 within the imaging ranges 6a and 6b. Cameras 5a and 5b convert the captured images into predetermined image data Da and Db and output them to the image processing device 8. Note that three or more cameras may be arranged with different angles for capturing images of the rolled material 4, or just one camera may be used if the location for camera placement is limited. By using two or more cameras, it becomes possible to acquire image data of the inclination of the rolled material 4, which is difficult to obtain with a single imaging range, and to perform a more detailed shape determination to check for abnormalities.

[0021] Figures 2(a) to 2(c) are schematic diagrams illustrating the relationship between the position of the looper and the position of the rolled material. Figures 2(a) to 2(c) show different states of the looper 3 and rolled material 4 as captured by camera 5b installed on the drive side within its imaging range 6b. As shown in Figures 2(a) to 2(c), camera 5b captures images of the looper 3 and rolled material 4 within its imaging range 6b. Although not shown, the state of the looper 3 and rolled material 4 as captured by camera 5a installed on the work side is similar, and camera 5a captures images of the looper 3 and rolled material 4 within its imaging range 6a.

[0022] Figure 2(a) shows the rolled material 4 in contact with the looper 3, with the looper 3 properly supporting the rolled material 4. Figure 2(b) shows the state in which the rolled material 4 has separated from the looper 3, resulting in plate separation. Figure 2(c) shows that although the rolled material 4 is in contact with the looper 3, the shape of the rolled material 4 is abnormal, and the looper 3 is not properly supporting the rolled material 4.

[0023] The image data Db represents the shapes of the looper 3 and rolled material 4 in Figures 2(a) to 2(c). The image processing device 8 processes this image data Db to determine whether or not there are any abnormalities.

[0024] The image processing device 8 processes the image data Db to measure the "plate separation degree DS". The image processing device 8 also processes the image data Db to determine the "plate shape". The "plate separation degree DS" is the distance between the roll of the looper 3 and the rolled material 4, and is the distance between the top of the roll of the looper 3 and the rolled material 4 vertically above the top.

[0025] The image processing device 8, for example, has a pre-defined threshold for the degree of plate separation DS, and determines that no plate separation has occurred if the measured value of the degree of plate separation DS based on the image data Db is less than the threshold. The image processing device 8 determines that plate separation has occurred if the measured value of the degree of plate separation DS is abnormally high.

[0026] Furthermore, the image processing device 8 has predetermined criteria for determining the shape of the rolled material 4. The criteria consist, for example, of criteria for determining normality and criteria for determining abnormality. The criteria for determining normality and the criteria for determining abnormality are set as training data for machine learning, and the image processing device 8 determines whether or not there is an abnormality in the shape of the rolled material 4 in the acquired image data Db.

[0027] Figure 3 is an example flowchart illustrating the operation of the plate separation prevention system according to the embodiment. The flowchart in Figure 3 shows that the image processing device 8 collects image data, including the shape of the rolled material 4 on the looper 3, captured by cameras 5a and 5b, as training data, and applies it to criteria for determining signs of plate separation.

[0028] As shown in Figure 3, in step S11, the image processing device 8 collects image data Da and Db, which include the shape of the rolled material 4 on the looper 3, captured by cameras 5a and 5b. When collecting image data, attribute information such as the material, thickness, and width of the rolled material 4 is associated with the image data and stored in a database.

[0029] In step S12, training data is created for the image processing device 8, which serves as a criterion for determining image data Da and Db. The determination criterion is set for each attribute information of the rolled material 4, for example, according to information stored in a database. The determination criterion is determined for each shape of the rolled material 4 on the looper 3, for example, as shown in Figure 2(c), by whether or not plate separation occurs. In order to collect a larger number of image data that can serve as determination criteria, the image processing device 8 may be configured to collect determinable image data collected from other rolling lines or other plants and use it as a database.

[0030] In step S13, the image processing device 8 applies the created judgment criteria, which are the learning data, to the learning model and operates the plate separation prevention system 100. The image processing device 8 adds and modifies the judgment criteria according to the set learning model and applies them to the learning model each time.

[0031] In step S14, for example, after a predetermined time has elapsed, it is evaluated whether the judgment made by the image processing device 8 was appropriate. The performance evaluation of the learning model may be performed offline by the operator using another program, or it may be done using an evaluation program installed in the image processing device 8.

[0032] In step S15, if it is determined that the performance evaluation in step S14 was sufficient, the process is terminated. If the performance evaluation in step S14 was not sufficient, the process proceeds to step S16.

[0033] In step S16, the learning model is modified based on the results of the performance evaluation.

[0034] In step S17, the modified learning model is further adjusted by modifying its parameters and applied to the plate separation prevention system 100 from step S13.

[0035] The cycle described above may be performed offline at predetermined intervals, or it may be performed online to optimize the learning model, for example, with a system in place where an operator monitors the process and can manually intervene in case of abnormalities.

[0036] Figure 4 is an example flowchart illustrating the operation of the plate separation prevention system according to the embodiment. Figure 4 shows the overall operation flow of the plate separation prevention system 100. As shown in Figure 4, in step S21, the image processing device 8 acquires image data Da and Db, which include the position and shape of the rolled material on the looper 3, captured by cameras 5a and 5b.

[0037] In step S22, the image processing device 8 processes the image data Da and Db to measure the degree of plate separation DS, which is the distance between the looper 3 and the rolled material 4 directly above the looper 3.

[0038] In step S23, the image processing device 8 compares the measured plate separation degree DS with a predetermined threshold. If the plate separation degree DS is less than the threshold, the image processing device 8 determines that plate separation has not occurred and proceeds to step S24. If the plate separation degree DS is greater than or equal to the threshold, the image processing device 8 determines that plate separation has occurred and proceeds to step S27.

[0039] In step S24, the image processing device 8, having determined that plate separation has not occurred, analyzes the shape of the rolled material 4 on the looper 3. In analyzing the shape of the rolled material 4, the device monitors how the shape of the rolled material 4 changes over time.

[0040] In step S25, the image processing device 8 uses a learned model to determine whether the shape of the rolled material and any changes in its shape indicate a precursor to plate separation. If the image processing device 8 determines that there is no possibility of plate separation, it terminates the process. If the image processing device 8 determines that there is a possibility of plate separation, it proceeds to step S26.

[0041] In step S26, the image processing device 8 determines that the shape of the rolled material 4 indicates an abnormal state that suggests the occurrence of plate separation, and sends a command to the controllers 10 and 11 to switch to manual intervention after a predetermined time. The controllers 10 and 11 also send a command to the HMI terminal to display a message prompting manual intervention.

[0042] If it is determined in step S23 that plate separation has occurred, in step S27 the image processing device 8 outputs a value for the degree of plate separation DS.

[0043] In step S28, the image processing device 8 generates an alarm indicating that plate separation has occurred and the rolling condition is abnormal, and sends it to the controllers 10 and 11. Upon receiving the alarm, the controllers 10 and 11 execute pre-set processes. When plate separation occurs, control becomes difficult, and if left unattended, the rolled material 4 may pile up between the rolling stands 1 and 2, potentially causing damage to the rolled material 4 and equipment. For example, the controllers 10 and 11 generate a command to emergency stop the rolling line in question and output it to each piece of equipment.

[0044] The effects of the plate separation prevention system 100 according to this embodiment will be explained. The plate separation prevention system 100 according to this embodiment includes an image processing device 8, which monitors the shape of the rolled material 4 on the looper 3 and uses image processing to determine whether the shape is a sign of an abnormality in the rolling state. The image processing device 8 determines whether the shape of the rolled material 4 is a sign of an abnormality in the rolling state abnormality If it is determined that there are signs of board separation, an alarm is output indicating that board separation is expected. Upon receiving the alarm, controllers 10 and 11 can then execute processes to prevent board separation.

[0045] The alarm generated and output by the image processing device 8, which indicates a precursor to plate separation, is not limited to one type, but can be of multiple types depending on the time-series pattern of changes in the shape of the rolled material 4. The image processing device 8 outputs the alarm set for each of these patterns to the controllers 10 and 11. The controllers 10 and 11 execute the processing set for each pattern to prevent plate separation, so that appropriate processing is performed before an abnormal condition that could cause plate separation occurs occurs.

[0046] In this way, a board separation prevention system that predicts board separation from the looper can be realized.

[0047] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]

[0048] 1, 2…Rolling stand, 3…Louper, 4…Rolled material, 5a, 5b…Camera, 8…Image processing device, 10, 11…Controller, 12…Motor, 13…Drive device, 14…Actuator, 100…Sheet release prevention system

Claims

1. A looper is installed between two rolling stands, and a camera captures the shape of the rolled material being transported on the looper to generate image data. An image processing device that, based on the aforementioned image data, determines signs of plate separation where contact between the looper and the rolled material is lost, and outputs a predetermined first command set according to the detection result to a control device that controls the two rolling stands and the looper. Equipped with, The image processing apparatus has a determination criterion that represents the shape of the rolled material in the state of impending plate separation, and by performing image processing on the image data, it analyzes the shape of the rolled material contained in the image data, and if the analyzed shape of the rolled material is the shape of the rolled material in the state of impending plate separation represented by the determination criterion, it determines that there is an impending plate separation. A plate separation prevention system in which the shape of the rolled material in the state of impending plate separation is such that the rolled material is in contact with the looper, and at least a portion of the rolled material between the rolling stand and the looper on the upstream side in the conveying direction of the rolled material is positioned at a height away from the looper.

2. The plate separation prevention system according to claim 1, wherein the image processing device measures the degree of plate separation, which is the distance between the looper and the rolled material, based on the image data, and outputs a predetermined second command to the control device, which is set to prevent accidents caused by plate separation, when the degree of plate separation is greater than or equal to a predetermined threshold.

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