A method and device for real-time paper breakage monitoring of a paper machine

Abstract

This application provides a real-time paper break monitoring method and device for paper machines. By identifying whether paper break events detected by different triggers are the same event, the method can accurately calculate the position of the paper break on the production line, achieving localization and tracking of the paper break. By classifying and marking each paper break event, the method enables rapid localization of the paper break defect for each event. Furthermore, by generating a grayscale waveform from the paper break video clips and identifying abnormal jumps in the waveform, the method achieves rapid identification and tracking of paper break events. The provided client software interface displays paper break records and other information arranged according to the actual production line process flow, providing a user-friendly interface and improving the user experience.

Description

Technical Field

[0001] This application relates to the fields of industrial automation and machine vision technology, specifically to a method and device for real-time paper breakage monitoring of a paper machine. Background Technology

[0002] During the paper production process, surface defects may occur in the paper due to environmental factors and the machine itself. These defects may lead to paper breaks, reduce paper quality, cause production line jams and shutdowns, greatly reduce papermaking efficiency, and increase production costs.

[0003] In existing methods, paper breakage events are usually identified through manual monitoring. This method requires a significant investment of manpower and time, and it is difficult to achieve real-time tracking and location of paper breakage events, as well as timely analysis of the causes of paper breakage. The level of intelligence is low, which seriously affects the quality and efficiency of papermaking. Summary of the Invention

[0004] This application aims to achieve real-time tracking and location of paper breakage events, improve the intelligence level of paper breakage monitoring, and enhance papermaking quality and efficiency. It provides a real-time paper breakage monitoring method for paper machines.

[0005] To achieve this objective, the following technical solution is adopted in this application: A method for real-time paper breakage monitoring of a paper machine is provided, comprising the following steps: S1 receives the paper break trigger signal generated by the trigger in response to the currently occurring paper break event, and then sends it to the video server and client software; S2, after receiving the trigger signal, the video server extracts and saves the video clip of the paper breakage from the video captured in real time by the camera at the location where the paper breakage occurred. S3, after receiving the trigger signal, the client software generates a paper break record and then displays the paper break video clip and / or the paper break record. Preferably, the method by which the client software generates the paper break record is as follows: The client software matches the process flow in which the paper breakage event occurs based on the binding relationship between the trigger that detects the paper breakage and the process flow, and then generates a paper breakage record for the matched process flow. The method by which the client software displays the video clip corresponding to the broken paper record is as follows: Based on the binding relationship between the workstation and the camera, the camera that monitors the process flow where the paper breakage event occurs is matched, and then the paper breakage video frame or video clip captured by the matched camera at the moment the trigger detects the paper breakage event is captured and displayed.

[0006] Preferably, the paper break record includes process flow information of the paper break event and the time when the trigger sensed the paper break event.

[0007] Preferably, the paper-breaking video segment, including the paper-breaking feature frame, is converted into a waveform of grayscale changes. The grayscale of the paper-breaking feature frame differs from that of a normal video frame where no paper breaking has occurred. The method for identifying the paper-breaking feature frame in the paper-breaking video segment using the waveform is as follows: The time point when the grayscale changes in the waveform is identified, and then the papermaking video frame collected at the identified time point is extracted as the identified paper breakage feature frame.

[0008] This application also provides a real-time paper breakage monitoring device for a paper machine, which can realize the aforementioned real-time paper breakage monitoring method for a paper machine, including: The instruction receiving module is used to receive the trigger signal generated when the trigger detects a paper breakage, and then send it to the video server and client software; The video server is used to extract and save the paper breakage video clip from the video captured in real time by the camera at the location where the paper breaks after receiving the trigger signal. The client software connects to the video server and is used to generate a paper break record after receiving the trigger signal, and then display the paper break video clip and / or the paper break record.

[0009] Preferably, the method by which the client software generates the paper break record is as follows: The client software matches the process flow in which the paper breakage event occurs based on the binding relationship between the trigger that detects the paper breakage and the process flow, and then generates a paper breakage record for the matched process flow. The method by which the client software displays the video clip corresponding to the broken paper record is as follows: Based on the binding relationship between the workstation and the camera, the camera that monitors the process flow where the paper breakage event occurs is matched, and then the paper breakage video frame or video clip captured by the matched camera at the moment the trigger detects the paper breakage event is captured and displayed.

[0010] Preferably, the paper break record includes process flow information of the paper break event and the time when the trigger detects the paper break event.

[0011] Preferably, the paper-breaking video segment, including the paper-breaking feature frame, is converted into a waveform of grayscale changes. The grayscale of the paper-breaking feature frame differs from that of a normal video frame where no paper breaking has occurred. The method for identifying the paper-breaking feature frame in the paper-breaking video segment using the waveform is as follows: The time point when the grayscale changes in the waveform is identified, and then the papermaking video frame collected at the identified time point is extracted as the identified paper breakage feature frame.

[0012] This application achieves precise calculation of the paper break's location on the production line by identifying whether different triggers detect the same paper break event, thus realizing the localization and tracking of paper breaks. By classifying and labeling each paper break event, it enables rapid localization of the paper break defect for each event. Furthermore, by generating a grayscale waveform from the paper break video clips and identifying abnormal jumps in the waveform, it achieves rapid identification and tracking of the paper break's timing. The provided client software interface displays paper break records and other information arranged according to the actual production line process flow, providing a user-friendly interface and enhancing the user experience. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly described below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a diagram illustrating the implementation steps of a real-time paper breakage monitoring method for a paper machine provided in an embodiment of this application. Figure 2 This is the overall architecture diagram of the paper breakage monitoring equipment; Figure 3 It is a schematic diagram of different stages in the process flow; Figure 4 This is a diagram showing the camera installation. Detailed Implementation

[0015] The technical solution of this application will be further described below with reference to the accompanying drawings and specific embodiments.

[0016] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual images. They should not be construed as limiting the scope of this application. To better illustrate the embodiments of this application, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0017] In the accompanying drawings of the embodiments of this application, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this application. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0018] In the description of this application, unless otherwise expressly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0019] The purpose of this application is to provide a paper breakage monitoring method and device based on real-time video and software interface display to address the paper breakage problem in paper machine production. The method first connects a video server to client software and a PLC trigger. Then, cameras and supplementary lighting devices are installed at various workstations in different papermaking processes. The client software displays the video footage captured by each camera in real time. When a paper breakage event occurs, the corresponding positional relationship between the trigger and the camera is used to extract and save the paper breakage video segment, generating a paper breakage record on the software interface. Simultaneously, the client software analyzes and processes the paper breakage video segment, automatically displaying the characteristic frames of the paper breakage defect during playback. This paper breakage monitoring device achieves effective data transmission between hardware and software, realizing functions such as recording paper breakage events and locating paper breakage defects. This facilitates production personnel's quick understanding and accurate tracking of each paper breakage event, enabling timely intervention and significantly improving the production efficiency of the paper machine.

[0020] This application provides a method for real-time paper breakage monitoring of a paper machine, such as... Figure 1 As shown, the steps include: S1 receives the paper break trigger signal generated by the trigger in response to the currently occurring paper break event, and then sends it to the video server and client software; S2, after receiving the trigger signal, the video server extracts and saves the video clip of the paper breakage from the real-time video captured by the camera at the location where the paper breakage occurred. When no paper breakage event is detected, the video server stores the video stream monitored by the camera in real time. S3: After receiving the trigger signal, the client software generates a paper break record and then displays the paper break video clip and / or the paper break record. Specifically, the real-time paper breakage monitoring method for a paper machine provided in this embodiment includes the following technical components: I. Establish a real-time intelligent paper breakage monitoring device that combines hardware and software. In this embodiment, a real-time paper breakage monitoring device combining hardware and software is constructed, such as... Figure 2 As shown, it includes: Video server. A video server has recording and storage capabilities, and is used to store real-time video data captured by cameras. Client software. The client software establishes a communication connection with the video server (preferably via UDP protocol), enabling real-time interaction and transmission of video clips and data information with the video server over the network. The client software not only provides secure and stable playback and display of the video stream captured in real-time by the camera, but also records and lists paper breakage events, and has editing functions for paper breakage video clips, such as adding a function to mark and process paper breakage defects.

[0021] The video server communicates with the paper machine's PLC paper break trigger via an I / O card. The I / O card receives the TTL signal from the PLC's paper break trigger. When a paper break event occurs, the I / O card detects the level change, and the video server immediately saves the paper break video segment in real time at high speed.

[0022] 2. Delineate the monitoring area for paper cuts and install video acquisition equipment such as cameras and strobe lights. In this embodiment, at least one paper breakage monitoring area is set up at each papermaking station on the paper machine production line. For example, a specified type of camera is installed on both the operating side and the transmission side of each station.

[0023] like Figure 3 As shown, a paper machine production line is typically divided into four processes: wire section, press section, dryer section, and winding section. Based on function, it can be further subdivided into nine sections: wire section, suction and transfer section, press section, pre-drying section, sizing section, post-drying section, calender, winding machine, and rewinder.

[0024] Based on the structural characteristics of each section, cameras are installed at 21 locations: headbox head, headbox tail, both sides of headbox, water jet, suction roller, before the first press, after the first press, after the second press, VAC cylinder 1, VAC cylinder 2, VAC cylinder 3, before sizing, after sizing, into the drying oven, before and after sizing (3 & 4#), out of the drying oven, out of the calender, winding, winding cylinder, first rewinder, and second rewinder. One camera is installed on the operating side and one on the drive side, for a total of 42 cameras. The camera installation positions are as follows: Figure 4As shown, the three positions of the press section are: before the first press, after the first press, and after the second press. The press section consists of one or more pairs of press rollers; it is not an independent component but a continuous station in the process section. Its main function is to dewater the paper sheet as much as possible using a double-roller squeezing method. In this application, the press section of the paper machine example has two sets of press rollers, hence the terms "first press" and "second press," specifically abbreviations for the first and second sets of press rollers. "Before the first press," "after the first press," and "after the second press" indicate the inlet and outlet positions of the corresponding press rollers. VAC cylinder is an abbreviation for Vacuum Cylinder Dryer. Its function is to use vacuum adsorption to tightly adhere the paper sheet to the drying cylinder, maintaining stability and a large contact area while steam heating to achieve dewatering and drying. In this application, the paper machine example is equipped with three continuous vacuum cylinder drying cylinders, each of which can be considered a position, abbreviated as VAC cylinder 1, VAC cylinder 2, and VAC cylinder 3.

[0025] The processes before the first pressing, after the first pressing, after the second pressing, and after sizing involve significant moisture interference. Therefore, a pinhole camera is preferred over a standard camera. Both standard and pinhole cameras are monochrome area array cameras.

[0026] In addition, besides the winding and winding cylinder positions which are in sufficiently lit environments, each camera station is equipped with strobe LED lights as supplementary lighting. The strobe lights use PWM (Pulse Width Modulation) signals to control the brightness. The higher the duty cycle of the PWM signal, the brighter the strobe light will be. Furthermore, the strobe lights use indirect air cooling to maintain stable brightness. To ensure the lifespan of both the cameras and strobe lights, a water-cooled enclosure is installed for further dustproofing, waterproofing, and cooling.

[0027] 3. The client software displays the real-time camera view, while the video server receives the paper-cut signal from the trigger and displays the paper-cut video clip through the client software. In this embodiment, the client software connects to the video server to acquire real-time monitoring footage captured by the camera. The client software interface can be switched to a four-part, nine-part, or sixteen-part display, and can zoom in to view the paper production line within the field of view of each part of the screen (each part of the screen represents a camera's field of view).

[0028] The client software is equipped with recording and image capture functions, storing captured video and image data in the video server. When individual observation of video segments is required, video and image clips from the paper machine production line can be imported from the video server for viewing and editing.

[0029] In this embodiment, the paper machine speed is typically different for each process flow; for example, the speeds of the press section and the winding section are different. Triggers are installed at different locations on the paper machine body, and the trigger signals are connected to the PLC access point of the paper breakage monitoring device through the DO point of the paper machine DCS. For example: trigger a is located in the wire section, and its speed is synchronized with the 5 production line stations in the wire section; trigger b is located in the press section, and its speed is synchronized with the 3 production line stations in the press section; trigger c is located in the drying section, and its speed is synchronized with the 8 production line stations in the drying section; trigger d is located in the winding section, and its speed is synchronized with the 5 production line stations in the winding section. The specific location and number of triggers need to be determined based on the actual situation of the paper machine body. The various processes, sections, and stations of the paper machine are expressed in Table 1 below: Table 1

[0030] After a paper breakage incident occurs, each process step through which the paper broke generates a paper breakage record, which is then displayed in a list on the client software interface. Simultaneously, the client software, based on the correspondence between the four process steps and the 21 papermaking stations where cameras are located, links the paper breakage record generated by the trigger signal at the start of each process step with the camera footage. For example, after trigger d emits a paper breakage signal, the software generates a paper breakage record named "Take-up Section." The "Take-up Section" record automatically includes video clips of the paper breakage captured by five cameras: calender exit, winding, winding cylinder, rewinder 1, and rewinder 2.

[0031] In addition, when a paper break occurs, the client software synchronously displays the paper break images from multiple cameras according to different workstations under the corresponding process flow, and each paper break image captures video frames or video clips with paper break characteristics.

[0032] In this embodiment, the method for extracting video clips of broken paper from real-time video is as follows: The client software internally stores the setting position information of each trigger and each camera on the paper machine, as well as the paper machine speed information at each trigger's setting position. By analyzing the relationship between the distance between the trigger and the camera and the paper machine speed, the travel time of the broken paper between the trigger and the camera can be obtained. For example, when a trigger detects a paper break and generates a paper break trigger signal, since the distance between the trigger and the camera, and the paper machine speed at each station are known, can be calculated. This time can then be added to the time when the trigger detects the paper break to obtain the instant the broken paper passes each camera. Finally, the time before and after this instant, for example, 0-120 seconds, can be extracted and saved as a video clip of the broken paper.

[0033] IV. The client software organizes paper breakage events, processes paper breakage records, and adds paper breakage information to the software interface. Different paper break events are displayed in different colors in the list on the software interface to distinguish them. A single paper break event consists of one or more paper break records.

[0034] Preferably, a single paper break record can be expanded to display video clips of paper breaks captured by all cameras under the same process flow. For example, the software interface can use a four-part, nine-part, or sixteen-part split screen to display video clips of paper breaks captured by each camera under the same process flow. More preferably, the right side of the paper break screen also shows the sequence of steps in each process flow of the paper machine production line and the positional relationship between the workstation cameras, indicating whether the camera is installed on the operating side or the drive side of the paper machine. The paper break screen is paired with camera icons. For example, when a camera icon turns red, the screen will show which side of the production line the red camera is installed on, which process flow it is operating in, and which workstation it is operating at.

[0035] Each video clip featuring a broken piece of paper can be played repeatedly at different speeds. Markers can also be added to the feature frames of the broken paper in the video, such as marking the defects in the broken paper from the image frames, to facilitate the subsequent observation and location of the broken paper features.

[0036] The client software also provides a grayscale waveform of the video clip to indicate the location of the paper breakage feature frame within the video clip. A stable waveform indicates that papermaking was normal during that time period and no paper breakage occurred. A sudden change in the waveform indicates an abnormality in papermaking at the point of change, indicating a paper breakage. In this embodiment, the paper breakage feature frame is quickly located based on the waveform. Then, the located feature frame is manually labeled with the type of paper breakage defect and named. A paper breakage bookmark is added to the video clip, and the video clip is then saved on the video server. The information in the paper breakage bookmark includes: the name of the workstation monitored by the camera that captured the paper breakage video clip, the time point when the paper breakage feature frame was generated, and the type and name of the paper breakage defect.

[0037] When reviewing the broken paper record again, you can replay the broken paper video clips that still have the broken paper bookmark, and you can directly locate and display the marked broken paper feature frames.

[0038] In summary, this application has the following beneficial effects: 1. The paper breakage monitoring device provided in this application, through the linkage of hardware and software, installs different types of cameras according to the actual situation of the papermaking process, and is equipped with strobe lights and water-cooled covers to effectively collect high-definition video while blocking interference from water mist and dust during the production process. At the same time, the cameras collect images of the entire production line, and combined with the paper breakage trigger installed at the paper machine speed, it can accurately calculate the position of the paper breakage on the production line.

[0039] 2. Compared to traditional paper machine monitoring equipment that lacks data analysis and historical playback functions, this application utilizes a video server for data storage and interaction, classifying and marking each paper breakage event to achieve rapid location of paper breakage defects for each event. Furthermore, by generating grayscale waveforms from the paper breakage video clips, the time point of the paper breakage is identified through abnormal jumps in the waveform, enabling rapid identification and tracking of paper breakage times.

[0040] 3. The client software interface provided in this application displays information such as paper breakage records in accordance with the actual production line process flow, which is user-friendly and improves the user experience.

[0041] It should be stated that the above-described specific embodiments are merely preferred embodiments and technical principles applied in this application. Those skilled in the art should understand that various modifications, equivalent substitutions, and variations can be made to this application. However, such variations, as long as they do not depart from the spirit of this application, should be within the scope of protection of this application. Furthermore, some terminology used in this application's specification and claims is not limiting but merely for ease of description.

Claims

1. A method for real-time paper breakage monitoring of a paper machine, characterized in that the steps include... include: S1 receives the paper break trigger signal generated by the trigger in response to the currently occurring paper break event, and then sends it to the video server and client software; S2, after receiving the trigger signal, the video server extracts and saves the video clip of the paper breakage from the video captured in real time by the camera at the location where the paper breakage occurred. S3, after receiving the trigger signal, the client software generates a paper break record and then displays the paper break video clip and / or the paper break record; The method by which the client software generates the paper break record is as follows: The client software matches the process flow in which the paper breakage event occurs based on the binding relationship between the trigger that detects the paper breakage and the process flow, and then generates a paper breakage record for the matched process flow. The method by which the client software displays the video clip corresponding to the broken paper record is as follows: Based on the binding relationship between the workstation and the camera, the camera that monitors the process flow where the paper breakage event occurs is matched, and then the paper breakage video frame or paper breakage video clip captured by the matched camera at the moment when the trigger detects the paper breakage event is captured and displayed. The paper-breaking video clip, including the paper-breaking feature frame, is converted into a waveform of grayscale changes. The grayscale of the paper-breaking feature frame differs from that of a normal video frame where no paper breakage has occurred. The method for identifying the paper-breaking feature frame in the paper-breaking video clip using the waveform is as follows: The time point when the grayscale changes in the waveform is identified, and then the papermaking video frame collected at the identified time point is extracted as the identified paper breakage feature frame.

2. The real-time paper breakage monitoring method for a paper machine according to claim 1, characterized in that, The paper break record includes process flow information of the paper break event and the time when the trigger sensed the paper break event.

3. A real-time paper breakage monitoring device for a paper machine, capable of implementing the real-time paper breakage monitoring method for a paper machine as described in any one of claims 1-2, characterized in that, include: The instruction receiving module is used to receive the trigger signal generated when the trigger detects a paper breakage, and then send it to the video server and client software; The video server is used to extract and save the paper breakage video clip from the video captured in real time by the camera at the location where the paper breaks after receiving the trigger signal. The client software connects to the video server and is used to generate a paper break record after receiving the trigger signal, and then display the paper break video clip and / or the paper break record.

4. The real-time paper breakage monitoring device for a paper machine according to claim 3, characterized in that, The method by which the client software generates the paper break record is as follows: The client software matches the process flow in which the paper breakage event occurs based on the binding relationship between the trigger that detects the paper breakage and the process flow, and then generates a paper breakage record for the matched process flow. The method by which the client software displays the video clip corresponding to the broken paper record is as follows: Based on the binding relationship between the workstation and the camera, the camera that monitors the process flow where the paper breakage event occurs is matched, and then the paper breakage video frame or video clip captured by the matched camera at the moment the trigger detects the paper breakage event is captured and displayed.

5. A real-time paper breakage monitoring device for a paper machine according to claim 4, characterized in that, The paper break record includes process flow information of the paper break event and the time when the trigger detected the paper break event.

6. The real-time paper breakage monitoring device for a paper machine according to claim 4, characterized in that, The paper-breaking video clip, including the paper-breaking feature frame, is converted into a waveform of grayscale changes. The grayscale of the paper-breaking feature frame differs from that of a normal video frame where no paper breakage has occurred. The method for identifying the paper-breaking feature frame in the paper-breaking video clip using the waveform is as follows: The time point when the grayscale changes in the waveform is identified, and then the papermaking video frame collected at the identified time point is extracted as the identified paper breakage feature frame.

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