Monitoring System and Monitoring Method

Abstract

To provide a monitoring system which can monitor abnormalities of a roll and a cooling device without stopping the roll and enables early discovery of abnormalities of the cooling device.SOLUTION: A monitoring system 1 monitors a roll 2 which receives heat transmitted from a hot material and is cooled by a cooling device 3. The monitoring system 1 includes: an imaging apparatus 6 which captures thermal images of the roll 2; and a monitoring device 7 which monitors abnormalities of the cooling device 3 based on the thermal images captured by the imaging apparatus 6.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a monitoring system and a monitoring method, and more particularly to a monitoring system and a monitoring method for monitoring a roll that receives heat from a hot material and is cooled by a cooling device.

Background Art

[0002] In a manufacturing line of a steel mill, various rolls are used. Examples of such rolls include a conveying roll for conveying a hot steel sheet (hereinafter referred to as a hot material) and a rolling roll for rolling a hot material. Since this type of roll is mainly composed of a metal material, when it receives heat from the hot material and its temperature rises, it may soften, its strength may decrease, and it may be prone to wear, or abnormalities such as scratches may occur on the surface of the roll. Therefore, for example, a cooling device for cooling the roll by spraying cooling water on the roll is provided in the vicinity of the roll.

[0003] Patent Document 1 describes an example of a device for monitoring abnormalities of a roll. The device includes a camera for photographing the surface of the roll, and is configured to detect defects on the surface of the roll based on an image photographed by the camera. Further, Patent Document 2 describes a method for monitoring the surface condition of a rolling roll for monitoring the wear of the rolling roll using a roll rotation speed meter and a sheet thickness measuring device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Since the device described in Patent Document 1 monitors defects, wear, etc. on the surface of the roll, it cannot monitor abnormalities in the roll cooling device that could cause such defects and wear on the roll surface. Therefore, in order to detect abnormalities in the cooling device, it is necessary to inspect each roll's cooling device one by one. Also, since a huge number of rolls are provided in the manufacturing line of the steel mill, a great deal of labor is required for the inspection of the cooling devices. Furthermore, considering the safety of the workers who inspect the cooling devices, the inspection of the cooling devices is limited to when the roll is stopped, that is, when the conveyance and rolling of the hot material by the roll are stopped. Therefore, there is a possibility that abnormalities in the cooling device cannot be detected early. Note that the monitoring method described in Patent Document 2 also has the same problems as those described above.

[0006] The present invention has been made to solve the above problems, and an object thereof is to provide a monitoring system and a monitoring method that can monitor abnormalities in a roll and a cooling device without stopping the roll, and moreover, can detect abnormalities in the cooling device at an early stage.

Means for Solving the Problems

[0007] In order to achieve the above object, the present invention [1] A monitoring system for monitoring a roll that is heated by heat transfer from a hot material and cooled by a cooling device, the monitoring system comprising: an imaging device that captures a thermal image of the roll; and a monitoring device that monitors an abnormality in the cooling device based on the thermal image captured by the imaging device. [2] The monitoring device according to the above [1], wherein the monitoring device estimates the temperature of the roll based on the thermal image, and determines that there is an abnormality in the cooling device when the estimated temperature of the roll exceeds a preset reference temperature. [3] The cooling device is disposed below the roll and includes a pipe through which a cooling fluid flowing in the axial direction of the roll flows, and a plurality of supply parts provided at predetermined intervals in the axial direction of the pipe for supplying the cooling fluid to the roll. The monitoring device determines that there is an abnormality in the supply part located below the portion where the temperature of the roll exceeds the reference temperature, in the monitoring system according to [2] above. [4] The monitoring device detects whether the roll is in contact with the hot material, and determines whether the temperature of the roll is within the reference temperature when the roll is not in contact with the hot material, in the monitoring system according to [2] above. [5] The monitoring device further includes a notification part for notifying an abnormality of the cooling device when it is determined that there is an abnormality in the cooling device, in the monitoring system according to any one of [1] to [4] above. [6] The imaging device captures the thermal image over the entire length of the roll in the axial direction of the roll, in the monitoring system according to [1] above. [7] The roll is at least one of a conveying roll constituting a conveying conveyor for conveying the hot material and a rolling roll for rolling the hot material, in the monitoring system according to [1] above. [8] A monitoring method for monitoring a roll that receives heat transfer from a hot material and is cooled by a cooling device, the method having a photographing step of photographing a thermal image of the roll and a monitoring step of monitoring the thermal image photographed in the photographing step. In the monitoring step, the temperature of the roll is specified based on the thermal image, and when the specified temperature of the roll exceeds a preset reference temperature, it is determined that there is an abnormality in the cooling device.

Advantages of the Invention

[0008] According to the present invention, since the abnormality of the cooling device is monitored based on the thermal image of the roll captured by the imaging device, the roll does not need to be stopped. In addition, since the cooling device can be constantly monitored, the abnormality of the cooling device can be detected at an early stage.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments according to the present invention will be described. FIG. 1 is a diagram showing an example of the monitoring system according to the present invention. The monitoring system 1 shown in FIG. 1 is configured to monitor an abnormality of a cooling device 3 that cools a roll 2 by monitoring an abnormality of the roll 2 that conveys a hot steel sheet (not shown; hereinafter referred to as a hot material).

[0011] The hot material means a material such as a steel sheet or a steel pipe heated to a predetermined temperature (for example, about 850°C to 1200°C). As an example, the roll 2 can include a plurality of conveying rolls that constitute a conveying conveyor for conveying the hot material to a predetermined location, a rolling roll for rolling the hot material to a preset thickness, and the like.

[0012] The conveying conveyor may be, for example, a conventionally known roller conveyor. The conveying conveyor is composed of a plurality of conveying rolls, and the conveying rolls include a driving roll and a driven roll and and are composed of. The driving roll is configured to receive torque generated by a driving force source (not shown) and rotate. The rotation of the driving roll is configured to apply a moving force along the conveying conveyor to the hot material in contact with the driving roll. The driving force source may be a motor as an example and is connected to the driving roll so as to be able to transmit torque. The driven roll is a roll called a free roll, and the hot material is placed on the driven roll. When a moving force is applied to the hot material by the above-described driving roll and the hot material moves, the driven roll in contact with the hot material is rotated by the hot material.

[0013] Each roll such as a conveying roll or a rolling roll is preferably formed of iron or an iron alloy in terms of strength or rigidity. These rolls are inevitably heated by the heat transferred from the hot material during the process of conveying or rolling the hot material. Therefore, a cooling device 3 for cooling each roll is provided. This is because when the temperature of each roll rises, each roll may soften or its strength may decrease, making it prone to wear, and there may be abnormalities such as scratches on the surface of each roll. To avoid these, the following will describe the case where the roll 2 cooled by the cooling device 3 is a conveying roll as an example.

[0014] Although not shown in detail, a plurality of rolls 2 are arranged parallel to each other and at a certain interval. In the example shown in FIG. 1, the cooling device 3 is provided below the roll 2.

[0015] In the example shown in FIG. 1, the cooling device 3 is a water-cooled cooling device. The cooling device 3 includes a plurality of pipes 4. Each pipe 4 is disposed below each roll 2 and extends in the axial direction of the roll 2. Also, the pipes 4 are arranged parallel to each other and at a certain interval. One end of each pipe 4 is closed so as to maintain a liquid-tight state. The other end of each pipe 4 is connected to a supply source (not shown) of a cooling fluid. On the upper side of each pipe 4, supply holes 5 for supplying the cooling fluid to the roll 2 are formed to penetrate in the plate thickness direction. The supply holes 5 are formed at a certain interval in the axial direction of the pipe 4. Note that nozzles may be provided in each supply hole 5. The cooling fluid may be, for example, industrial water (hereinafter referred to as industrial water). The above-described supply holes 5 correspond to the supply portion of the present invention.

[0016] Above the roll 2, a camera 6 corresponding to the imaging device of the present invention is installed. Specifically, the camera 6 is installed at a position where it does not contact the hot material conveyed by the conveyor and can image the entire length of the roll 2. Preferably, the camera 6 is installed at a position where it can image a plurality of rolls 2 at once. As an example, the camera 6 is a thermal camera and is configured to continuously or intermittently capture thermal image data (hereinafter simply referred to as image data) of the surface of the roll 2. In this embodiment, during the operation of the conveyor, the camera 6 continuously captures image data of the surface of the roll 2. The thermal image data captured by the camera 6 corresponds to the thermal image of the present invention.

[0017] In the monitoring system 1 shown in FIG. 1, a monitoring device 7 for determining an abnormality of the cooling device 3 based on the image data captured by the camera 6 is provided. The monitoring device 7 is mainly composed of a microcomputer, performs calculations based on pre-stored data, arithmetic expressions, acquired data, etc., and is configured to output the calculation results as output data and control command signals. In the example shown in FIG. 1, the image data captured by the camera 6 is input to the monitoring device 7. The monitoring device 7 further includes a monitor 8, a determination unit 9 that estimates the temperature of the roll 2 based on the image data and determines an abnormality of the cooling device 3, and a notification unit 10 that notifies the surrounding of the abnormality when the determination unit 9 determines that there is an abnormality in the cooling device 3.

[0018] The monitor 8 may be a conventionally known monitor. The monitor 8 is configured to display the image data captured by the camera 6. The notification unit 10 is configured to notify the surrounding of the abnormality of the cooling device 3, specifically, the operator, by, for example, voice, sound, light, or vibration. Further, the notification unit 10 may be configured to display the determination result of the abnormality of the cooling device 3 by the determination unit 9 on the monitor 8.

[0019] In the conveyor with the above-described configuration, when a hot material is conveyed, the temperature of each roll 2 rises due to receiving heat from the hot material. Therefore, at least while the hot material is being conveyed by the conveyor, a cooling fluid is supplied to each roll 2 by the cooling device 3 so that each roll 2 is cooled. In the example shown in FIG. 1, a pipe 4 is arranged below the roll 2, and a plurality of supply holes 5 are provided above the pipe 4. Therefore, industrial water is sprayed in a spray form from each supply hole 5 toward the outer peripheral surface located below the roll 2. Thereby, the roll 2 is cooled over the entire length.

[0020] FIG. 2 is a flowchart for explaining an example of control executed by the monitoring device 7 of the monitoring system 1 according to the present invention. The control example shown in FIG. 2 is repeatedly executed at predetermined short time intervals during the operation of the conveyor. In the control example shown in FIG. 2, first, the determination unit 9 determines whether or not a hot material is being conveyed by the conveyor (step S1). That is, it is determined whether or not the roll 2 to be monitored is in contact with the hot material. This can be done, for example, by providing a position sensor (not shown) on the conveyor and detecting the presence or absence of the hot material on the conveyor by the position sensor. Alternatively, it may be done by detecting the current value for the drive roll. If it is positively determined in step S1, the hot material is being conveyed by the conveyor, and the image data of the roll 2 cannot be taken. Also, while the roll 2 is in contact with the hot material, since the influence of the heat received by the roll 2 from the hot material is higher than the influence of the cooling received by the roll 2 from the cooling device 3, it is difficult to detect abnormalities in the roll 2 or the cooling device 3. Therefore, the determination in step S1 is repeatedly executed until it is negatively determined in step S1.

[0021] On the other hand, if a negative determination is made in step S1, it is determined whether the temperature of each roll 2 is within the reference temperature based on the image data of roll 2 captured by camera 6 (step S2). This is done by detecting the presence or absence of data exceeding the reference temperature in the image data. FIG. 3 is a diagram showing an example of the image data. As shown in FIG. 3, the image data is data indicating the temperature distribution of each roll 2, and the temperature of each roll 2 is specified based on the image data. Then, the estimated temperature of roll 2 is compared with the reference temperature. If there is a portion of roll 2 that exceeds the reference temperature, or if the temperature of roll 2 exceeds the reference temperature over the entire length of roll 2, a negative determination is made in step S2. When there is a portion of roll 2 that exceeds the reference temperature, the portion appears in a streak shape as shown in FIG. 3. When the temperature of roll 2 exceeds the reference temperature over the entire length of roll 2, the portion appears over the entire roll 2 as shown by dots in FIG. 3. Note that the process of imaging roll 2 by camera 6 corresponds to the imaging process of the present invention, and the process of determining whether the temperature of each roll 2 is within the reference temperature based on the image data corresponds to the monitoring process of the present invention.

[0022] The reference temperature is, for example, the upper limit value of the temperature of roll 2 at which roll 2 can be used without degrading the durability of roll 2, and can be preset according to the material of roll 2 and experiments. In the present embodiment, as an example, the reference temperature is 100°C. If there is no data exceeding the reference temperature in the image data, that is, if the temperature of each roll 2 is within the reference temperature, a positive determination is made in step S2. In that case, the process returns to step S1.

[0023] If the determination in step S2 is negative, the determination unit 9 identifies the position of the supply hole 5 corresponding to the portion exceeding the reference temperature in roll 2 (step S3). As described above, since the supply holes 5 are located below each roll 2, based on the image data, the supply holes 5 located below the portion exceeding the reference temperature in roll 2 can be identified. Specifically, in step S2, if it is determined that there is a portion exceeding the reference temperature in any part of roll 2, it is determined that an abnormality has occurred in the supply hole 5 located below the portion exceeding the reference temperature. Also, a case where the temperature of roll 2 exceeds the reference temperature over the entire length of any one of the plurality of rolls 2 will be described. In that case, it is determined that an abnormality has occurred in each of the three cooling devices 3 for that roll 2, that is, the pipe 4 located below that roll 2, or the supply holes 5 formed in the pipe 4.

[0024] Next, the determination result in step S3 described above is input from the determination unit 9 to the notification unit 10, and the abnormality of the cooling device 3 is notified to the operator by the notification unit 10 (step S4). When notifying the operator of the abnormality of the cooling device 3 by the notification unit 10 by means of sound, sound, light, vibration, etc., the supply hole 5 specified in step S3 may be displayed on the monitor 8. Then, this flow is terminated once.

[0025] As described above, in the monitoring system 1 having the above-described configuration, by monitoring each roll 2 based on the image data of each roll 2, an abnormality in the cooling device 3 for cooling each roll 2 can be detected. Also, since the abnormality of the cooling device 3 is monitored based on the temperature of roll 2, the abnormal location of the cooling device 3 can be pinpointed, and maintenance such as inspection and repair can be promptly performed on the abnormal location. Furthermore, when there is no hot material on the conveying conveyor within the monitoring range by the camera 6, it is determined whether the temperature of roll 2 is within the reference temperature. Therefore, even when the hot material is being conveyed by the conveying conveyor, that is, without stopping the conveyance of the hot material by the conveying conveyor, the cooling abnormality of roll 2 and the abnormality of the cooling device 3 can be monitored.

[0026] Note that the present invention is not limited to the above-described embodiments. In the above-described embodiments, the monitoring device 7 determines the presence or absence of cooling abnormality of the roll 2, that is, the abnormality of the cooling device 3. Instead, the presence or absence of the abnormality of the cooling device 3 may be determined by a person. In this case, in the flowchart shown in FIG. 2, the determinations in step S1 and step S2 are made by a person. For example, the image data, that is, the temperature distribution and the maximum temperature of each roll 2 are displayed on the monitor 8, and the image data displayed on the monitor 8 is monitored by a person. Then, when it is not during the conveyance of the hot material and the surface temperature (maximum temperature) of the roll 2 exceeds a predetermined reference temperature, a person determines that there is an abnormality in the cooling device 3. When it is determined that there is an abnormality in the cooling device 3, maintenance such as inspection and repair of the cooling device 3 is performed.

[0027] Further, in the above-described embodiments, the monitoring system 1 according to the present embodiment has been described by taking the conveyance roll 2 of the conveyance conveyor as an example. However, the present invention is not limited to the conveyance roll 2, and other rolls such as rolling rolls used in a manufacturing line of a steel mill may be used. Further, the cooling device 3 is not limited to the spray method or the external cooling method for injecting the cooling fluid. For example, an internal cooling type cooling device that forms a flow path for the cooling fluid inside the roll 2 and cools the roll 2 by flowing the cooling fluid through the flow path may be used. Instead of industrial water, oil, air, or the like may be used as the cooling fluid. Further, in the above-described embodiments, the abnormality of the cooling device 3 is determined based on whether or not the surface temperature of the roll 2 is within the reference temperature. Instead, the temperature difference between a plurality of rolls 2 may be monitored, and when the temperature difference exceeds a threshold value, it may be configured to determine that there is an abnormality in the cooling device 3. Alternatively, the temperature difference between a portion of the roll 2 having a higher temperature than other portions and a portion of the other portions having a lower temperature may be monitored, and when the temperature difference exceeds a threshold value, it may be configured to determine that there is an abnormality in the cooling device 3.

Explanation of Reference Numerals

[0028] 1 Monitoring system 2 Roll 3 Cooling device 4 pipes 5 supply holes (an example of a supply unit) 6 cameras (an example of an imaging device) 7 monitoring device 8 monitor 9 determination unit 10 notification unit

Claims

1. A monitoring system for monitoring a roll that is heated by heat transfer from a hot material and cooled by a cooling device, comprising: an imaging device that captures a thermal image of the roll; a monitoring device that monitors an abnormality of the cooling device based on the thermal image captured by the imaging device, wherein the monitoring device estimates the temperature of the roll based on the thermal image, and determines that there is an abnormality in the cooling device when the estimated temperature of the roll exceeds a preset reference temperature.

2. The cooling device is disposed below the roll and includes a pipe through which a cooling fluid that extends in the axial direction of the roll flows, and a plurality of supply portions that are provided at predetermined intervals in the axial direction of the pipe and supply the cooling fluid to the roll. The monitoring system according to claim 1, wherein the monitoring device determines that there is an abnormality in a supply portion located below a portion where the temperature of the roll exceeds the reference temperature.

3. The monitoring system according to claim 1, wherein the monitoring device detects whether the roll is in contact with the hot material, and determines whether the temperature of the roll is within the reference temperature when the roll is not in contact with the hot material.

4. When the monitoring device determines that there is an abnormality in the cooling device, the monitoring device further includes a notification unit that notifies the abnormality of the cooling device. The monitoring system according to any one of claims 1 to 3.

5. The monitoring system according to any one of claims 1 to 3, wherein the imaging device captures the thermal image over the entire length of the roll in the axial direction of the roll.

6. The roll is at least one of a conveying roll that constitutes a conveying conveyor for conveying the hot material and a rolling roll that rolls the hot material. The monitoring system according to any one of claims 1 to 3.

7. A monitoring method for monitoring a roll that is heated by heat transfer from a hot material and cooled by a cooling device, comprising: an imaging step of capturing a thermal image of the roll; a monitoring step of monitoring the thermal image captured in the imaging step, wherein in the monitoring step, the temperature of the roll is specified based on the thermal image, and when the specified temperature of the roll exceeds a preset reference temperature, it is determined that there is an abnormality in the cooling device. ​ ​

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