Shell-and-tube heat exchanger tube hole positioning method based on man-machine interaction

Abstract

The invention discloses a tubular heat exchanger tube hole positioning method based on man-machine interaction, and belongs to the technical field of heat exchanger cleaning. The method comprises the following steps: S1, equipment initialization and machinery zero returning; S2, visual parameter setting; s3, anchor point definition; through a man-machine interaction mode, the control unit collects and stores physical coordinates of the starting pipe hole and the ending pipe hole, and the physical coordinates serve as a first anchor point (Ps) and a second anchor point (Pe) respectively; s4, parameterization generation is carried out; a linear interpolation algorithm is adopted, and theoretical coordinates (Pi) of all the n middle pipe holes are automatically calculated and generated; s5, constructing an array; and the steps S2-S4 are repeated, and the upper computer processing unit forms a pipe hole distribution diagram. According to the method, a complete pipe hole distribution digital map is efficiently and accurately generated in a parameterization mode that one line is defined by two points.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of heat exchanger cleaning, and particularly relates to a tube hole positioning method for a tube heat exchanger based on human-computer interaction. BACKGROUND

[0002] The tube heat exchanger is an indispensable key equipment in the fields of petroleum, chemical industry, energy and the like. In a long-term operation process, the tube bundle inside the tube heat exchanger will have substances such as dirt and coking attached to the inner wall of the tube hole, which will cause the heat exchange efficiency to decrease significantly and increase energy consumption. Therefore, regular and efficient cleaning of the tube bundle of the heat exchanger is an important link to guarantee the safety and economic benefits of industrial production.

[0003] The current tube hole cleaning positioning technology mainly has the following several ways and limitations.

[0004] First, traditional manual cleaning: completely relying on manual operation, high safety risk, high labor intensity, poor working environment, low cleaning efficiency, and unstable cleaning quality, which is difficult to meet the requirements of modern industrial production.

[0005] Second, semi-automatic positioning equipment: the physical exertion of the operator is reduced through mechanical assistance, but the movement and hole positioning of the equipment still need to be completed manually by the operator, and the speed and accuracy of positioning are highly dependent on the proficiency and responsibility of the operator, and real automation cannot be achieved.

[0006] Third, full-automatic positioning scheme based on machine vision: this scheme is the mainstream direction of current automation upgrade, but it faces insurmountable challenges in complex industrial sites; first, poor environmental adaptability; water stains, oil stains, rust marks and irregular metal reflections are generally present on the tube plate surface, plus the complex and changeable lighting conditions in the field, which will seriously interfere with the image quality, resulting in a significant decrease in the recognition rate and positioning accuracy of the visual recognition algorithm, and even failure; second, high system cost; a high-resolution industrial camera, a professional light source system, a high-performance image processing industrial computer and complex image recognition software need to be configured, which significantly increases the manufacturing cost of the equipment and the maintenance cost in the later period; third, complex calibration and debugging; the vision system is extremely sensitive to the physical position of the equipment and the camera parameters, and after each equipment displacement, component replacement or change of the working environment, professional technicians need to perform re-calibration and debugging, the operation process is tedious, which affects the operation efficiency and the ease of use of the equipment.

[0007] In summary, the existing technology either has a low degree of automation or, although the degree of automation is high, the cost, environmental adaptability and operation convenience are difficult to balance. Therefore, the market urgently needs a new type of tube hole automatic positioning technology that can not rely on a complex machine vision system and simultaneously balance the cost, efficiency, accuracy and reliability. SUMMARY

[0008] In order to overcome the deficiencies in the background art, the present application provides a kind of based on man-machine interaction's tube hole positioning method of tube heat exchanger, it aims at, provide a kind of cost low, operation is simple, environmental adaptability is strong, positioning accurate stable tube hole positioning method, utilize the inherent regular geometric distribution (such as linear or array) of heat exchanger tube hole essence characteristics, the macroscopic guidance of operator is combined with the precise calculation of computer, by the parameterization mode of " two points determine a line", complete tube hole distribution digital map is generated efficiently and accurately.In the tube hole positioning process of tube heat exchanger, avoid the problems such as high cost, complex operation process, poor environmental adaptability and unstable positioning accuracy caused by excessive dependence on machine vision system.

[0009] To achieve the above object, the present application provides the following technical scheme: a kind of based on man-machine interaction's tube hole positioning method of tube heat exchanger, including the following steps:

[0010] S1: equipment initialization and mechanical zeroing;Start control system, execute mechanical execution unit zero program, make mechanical execution unit establish unified mechanical coordinate system origin;

[0011] S2: visual parameter setting;Before positioning operation, set the visual rendering parameters of tube hole on the host computer processing unit through the man-machine interface of host computer processing unit;

[0012] S3: anchor point definition;By man-machine interaction, control the terminal of mechanical execution unit, make it align the starting tube hole and the end tube hole of a column or a row tube hole on target tube sheet in turn, and the physical coordinates of the starting tube hole and the end tube hole are collected and stored by control unit, as first anchor point (Ps) and second anchor point (Pe) respectively;

[0013] S4: parameterization generation;The operator inputs the number n of intermediate tube holes between the first anchor point and the second anchor point through the interactive interface of host computer processing unit;The system automatically calculates and generates the theoretical coordinates (Pi) of all n intermediate tube holes based on the first anchor point coordinates (Ps), the second anchor point coordinates (Pe) and the number n of intermediate tube holes using linear interpolation algorithm;

[0014] S5: array construction;Repeat steps S2-S4 to complete data acquisition and graphical identification generation of all tube holes to be positioned on target tube sheet, and the host computer processing unit forms a tube hole distribution map.

[0015] As further optimization, after step S5, it further includes step S6;S6: graphical checking and editing: compare the tube hole distribution map generated by the host computer processing unit interface with the actual heat exchanger tube sheet, and the operator edits the tube hole distribution map through the interactive interface, and the editing operation includes deleting tube hole or setting tube hole as invalid hole.

[0016] As a further optimization, in step S4, the calculation formula of the linear interpolation algorithm is:

[0017]

[0018] As a further optimization, steps S1-S5 are implemented based on a positioning system for tube holes of a shell-and-tube heat exchanger, the positioning system comprising a mechanical execution unit, a control unit and an upper computer processing unit; the mechanical execution unit has a terminal that can be positioned in a two-dimensional space, and is equipped with a servo motor and a sensor system that can accurately feedback its physical coordinates; the control unit comprises a PLC, which is used to receive instructions from the upper computer processing unit, drive the mechanical execution unit to move, and collect and upload the physical coordinates of the terminal of the mechanical execution unit; the upper computer processing unit has a human-computer interaction software running, which internally comprises at least an anchor point management module, an interpolation calculation module and a graphic rendering and interaction module; the anchor point management module is used to receive and store anchor point coordinates defined by an operator; the interpolation calculation module is used to perform linear interpolation calculation according to the anchor point coordinates and the input number of tube holes; and the graphic rendering and interaction module is used to process parameter input including visual rendering parameters, and generate a tube hole distribution diagram.

[0019] As a further optimization, the graphic rendering and interaction module is also used to provide interactive functions of point selection, deletion and marking of hole positions as invalid holes for subsequent work to avoid obstacle recognition.

[0020] The advantages of the present application are as follows: first, the cost is significantly reduced: by abandoning the expensive machine vision hardware (industrial camera, professional light source, etc.) and related image processing software, the manufacturing cost and later maintenance cost of the device are greatly reduced. In addition, abandoning the vision device also avoids the errors brought by visual recognition. Second, strong adaptability: the positioning process does not depend on optical imaging, fundamentally avoiding the interference of environmental factors such as dirt, water stains, reflection and on-site light changes on the tube plate surface, and can maintain high stability and high reliability in various harsh working conditions. In addition, for tube plates with irregular tube hole distribution, as long as they have the characteristic of straight-line uniform distribution of tube holes, the present method can be used for positioning and marking, and a program of an upper computer processing unit can adapt to the tube hole positioning and marking work of various shell-and-tube heat exchangers, and has strong universality. Third, the operation process is greatly simplified: the interactive process is intuitive, and an operator can complete the complex tube hole layout definition through the simple combination of "zeroing-setting-moving-clicking-inputting numbers-correction", which greatly improves the use convenience and operation efficiency of the device. In addition, since the present method is calculated by using the "straight-line uniform distribution characteristic", an operator who learns to use the present method can clean various shell-and-tube heat exchangers, and the requirements for the operator are reduced, which is easy to learn and operate, has good operability, and reduces labor costs. Fourth, high positioning accuracy and reliability: the uniqueness and stability of the coordinate reference are ensured through the initial mechanical zeroing, the key anchor point coordinates are directly obtained from the closed-loop position feedback of the servo system, the accuracy is high and there is no cumulative error, combined with the precise interpolation algorithm and the final manual correction, the high precision and high accuracy of all generated hole positions are ensured. In addition, since the present method is calibrated by using the "straight-line uniform distribution characteristic", only one direction coordinate needs to be moved during calibration, and the other direction coordinate remains unchanged, for example, the Y coordinate remains unchanged and only the X coordinate is moved, which can ensure that the Y coordinates of all hole positions in the same straight line direction remain unchanged, overcome the system error in the Y coordinate direction, and improve the calibration accuracy.

[0021] In summary, the present application generates a complete tube hole distribution digital map efficiently and accurately by using the "two-point-to-one-line" parameterization method. The problems of high cost, complex operation process, poor environmental adaptability and unstable positioning accuracy caused by excessive dependence on machine vision systems are avoided. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The figure is a system structure schematic diagram of an embodiment of the present application;

[0023] Figure 2 The figure is a screenshot of the human-computer interaction interface of the upper computer processing unit of an embodiment of the present application, showing the state of the generated complete tube hole distribution map;

[0024] Figure 3Another screenshot of the man-machine interactive interface of the host computer processing unit of the embodiment of the present application shows the process of generating a row of tube holes by defining two anchor points and performing linear interpolation.

[0025] In the figure: 1. heat exchanger, 11. first anchor point, 12. second anchor point, 13. invalid hole, 2. mechanical execution unit, 3. host computer processing unit, 4. control unit, 5. operator. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings of the present application. Obviously, the described embodiments are only some preferred embodiments of the present application, but not all the embodiments. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application, and are not intended to limit the protection scope of the present application.

[0027] Embodiment; please refer to Figures 1-3 .

[0028] The present embodiment provides a tube hole positioning method for tube heat exchanger based on man-machine interaction. The system used mainly includes a heat exchanger cleaning device (as a mechanical execution unit 2) installed on a truss, the movement of which is driven by a PLC (as a control unit 4) in a control cabinet, and an operator 5 performs all operations and monitoring through a host computer processing unit 3 (as a host computer processing unit 3).

[0029] Step one: system initialization and parameter setting: start the host computer processing unit 3 software, connect the PLC in the control cabinet through communication, execute the "mechanical zero" instruction, and automatically return the axes of the cleaning device to the original point to establish a stable mechanical coordinate system. The operator creates a new project on the software interface and sets the "display diameter" of the tube hole in the project settings, for example, set it to 50 pixels, so that the hole position map generated later is clear on the screen.

[0030] Step two: reference row definition and parameterized generation: the operator manually controls the execution terminal (such as the hole gun tube) of the cleaning device through the direction keys or handles on the interface, and moves to the first hole position of any row (usually the longest row for easy observation) on the tube sheet of the heat exchanger 1. After confirming the alignment, click the "current position insertion" or similar button on the interface, and the system records the current coordinates as the first anchor point 11 (Ps), and generates a prominent graphical identifier (such as a dark black dot in Figure 3 ) on the interface corresponding to the position.

[0031] Subsequently, the operator continues to move the device to the last hole position of the row, and performs the "current position insertion" operation again, and the system records the coordinates as the second anchor point 12 (Pe) and generates a second identifier on the interface.

[0032] Then, the operator clicks the two anchors with the mouse and clicks the "linear interpolation" function. The system pops up a dialog box prompting the input of the number of holes between the two anchors. The operator visually observes and inputs the value n and confirms. The system will automatically calculate the coordinates of all the intermediate hole positions according to the linear interpolation formula and render all the newly generated hole positions on the interface (e.g., the gray dots in FIG. 6). Figure 3 The calculation formula is as follows:

[0033]

[0034] The formula is equivalent to calculating the X and Y coordinates respectively:

[0035]

[0036]

[0037] Step three: array construction; the operator repeats step two to complete the definition of all the tube holes row by row. For the heat exchanger 1 with a very regular arrangement, the system can also provide a "fast mode": after the first row is defined, the system automatically calculates the standard horizontal and vertical hole spacing. The subsequent row only needs to define a starting point, and the system can automatically calculate the hole positions of the entire row or column. Finally, the complete tube hole distribution diagram as shown in FIG. 7 is formed on the interface of the host computer processing unit 3. Figure 2

[0038] Step four: graphical checking and editing: after all the hole positions are initially generated, the operator compares the tube hole diagram on the interface with the actual tube plate. For the hole positions in the diagram that are redundant, they can be directly selected and deleted. For the hole positions that cannot be safely accessed due to obstacles in front of the tube plate, or the hole positions that do not need to be worked on due to self-plugging, etc., they can be selected and marked as "invalid holes 13". In this way, the subsequent automatic operation program can identify and actively bypass these invalid holes 13 when planning the path, thereby effectively preventing the cleaning equipment from colliding with obstacles and ensuring the safety of the operation.

[0039] Step five: after the positioning of all the holes is completed, according to the generated tube hole distribution diagram, the control unit 4 controls the mechanical execution unit 2 to clean all the tube holes one by one according to the tube hole distribution diagram. At this time, the cleaning operation is automatically executed, and personnel are away from the tube plate, avoiding working in harsh environments and reducing labor intensity.

[0040] The advantages of the embodiment are as follows.

[0041] ​(1) Significantly reduced costs: By eliminating expensive machine vision hardware (industrial cameras, professional light sources, etc.) and related image processing software, the manufacturing cost and subsequent maintenance expenses of the equipment are greatly reduced. In addition, eliminating vision equipment also avoids errors caused by visual recognition.

[0042] (2) Excellent adaptability: The positioning process does not rely on optical imaging, fundamentally avoiding interference from environmental factors such as dirt, water stains, reflections, and changes in ambient light on the tube sheet surface. It can maintain high stability and high reliability under various harsh working conditions. In addition, for tube sheets with irregular tube hole distribution, as long as they have the characteristic of linear and uniform tube hole distribution, this method can be used for positioning and marking. A program of the host computer processing unit 3 can adapt to the tube hole positioning and marking work of various shell and tube heat exchangers 1, which has strong versatility.

[0043] (3) The operation process is greatly simplified: The interactive process is intuitive. Operators can complete the definition of complex tube hole layouts by simply combining "zeroing-setting-moving-clicking-inputting numbers-comparing and correcting", which greatly improves the ease of use and work efficiency of the equipment. In addition, since this method is calculated based on the "straight-line uniform distribution characteristic", one operator who learns to use this method can clean various shell and tube heat exchangers 1, which reduces the requirements for operators, is easy to learn and use, has good operability, and reduces labor costs.

[0044] (4) High and reliable positioning accuracy: Initial mechanical zeroing ensures the uniqueness and stability of the coordinate reference. The coordinates of key anchor points are directly derived from the closed-loop position feedback of the servo system, resulting in high accuracy and no cumulative error. Combined with precise interpolation algorithms and final manual verification, this guarantees high precision and accuracy for all generated hole positions. Furthermore, since this method utilizes the "uniform distribution of straight lines" for calibration, each calibration only requires movement in one direction while keeping the other direction unchanged. For example, if the Y-coordinate remains constant, only the X-coordinate is moved. This ensures that the Y-coordinate of all hole positions along the same straight line remains constant, overcoming systematic errors in the Y-coordinate direction and improving calibration accuracy.

[0045] In summary, this embodiment efficiently and accurately generates a complete digital map of pipe hole distribution through a parametric method of "two points determining a line." This avoids the problems of high cost, complex operation procedures, poor environmental adaptability, and unstable positioning accuracy that arise from over-reliance on machine vision systems.

[0046] The part of the present application not described in detail is the prior art; for those skilled in the art, any combination of the technical features of the above-mentioned embodiments can be made, in order to make the description simple, all possible combinations of each technical feature in the above-mentioned embodiments are not described, however, as long as the combination of these technical features does not exist contradictory, it should be considered that it is within the scope of the present application. The scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for positioning tube holes of a shell-and-tube heat exchanger based on human-computer interaction, characterized in that, Comprising the following steps: S1: device initialization and mechanical zeroing; starting the control system, executing the mechanical execution unit (2) zeroing program, and making the mechanical execution unit (2) establish a unified mechanical coordinate system origin; S2: visual parameter setting; before positioning operation, setting the visual rendering parameters of the tube holes on the upper computer processing unit (3) through the human-computer interaction interface of the upper computer processing unit (3); S3: anchor point definition; through human-computer interaction, controlling the terminal of the mechanical execution unit (2) to align the starting tube hole and the ending tube hole of a certain column or a certain row of tube holes on the target tube sheet in turn, and collecting and storing the physical coordinates of the starting tube hole and the ending tube hole by the control unit (4), as the first anchor point (11) coordinate (Ps) and the second anchor point (12) coordinate (Pe) respectively; S4: parameterized generation; inputting the number n of intermediate tube holes between the first anchor point (11) and the second anchor point (12) by the operator through the interactive interface of the upper computer processing unit (3); based on the first anchor point (11) coordinate (Ps), the second anchor point (12) coordinate (Pe) and the number n of intermediate tube holes, the system automatically calculates and generates the theoretical coordinates (Pi) of all n intermediate tube holes by using linear interpolation algorithm; S5: array construction; repeating steps S2-S4 to complete data collection and graphical identification generation of all tube holes to be positioned on the target tube sheet, and the upper computer processing unit (3) forms a tube hole distribution map.

2. The method of claim 1, wherein, After step S5, step S6 is further included; S6: graphical checking and editing: comparing the tube hole distribution map generated by the interface of the upper computer processing unit (3) with the actual heat exchanger tube sheet, and performing editing operation on the tube hole distribution map by the operator through the interactive interface, the editing operation including deleting tube holes or setting tube holes as invalid holes (13).

3. The method of claim 1, wherein, In step S4, the calculation formula of the linear interpolation algorithm is:

4. The method of claim 1, wherein, Steps S1-S5 are realized based on a tube positioning system of a column tube heat exchanger, and the positioning system comprises a mechanical execution unit (2), a control unit (4) and an upper computer processing unit (3); The mechanical execution unit (2) has a terminal that can be positioned in a two-dimensional space, and is equipped with a servo motor and a sensor system that can accurately feedback the physical coordinates thereof; The control unit (4) comprises a PLC, which is used for receiving instructions of the upper computer processing unit (3), driving the mechanical execution unit (2) to move, and collecting and uploading the physical coordinates of the terminal of the mechanical execution unit (2); The upper computer processing unit (3) has a running human-computer interaction software, which at least includes an anchor point management module, an interpolation calculation module and a graphical rendering and interaction module; The anchor point management module is used for receiving and storing the anchor point coordinates defined by the operator; The interpolation calculation module is used for performing linear interpolation calculation according to the anchor point coordinates and the input number of tube holes; The graphical rendering and interaction module is used for processing parameter input including visual rendering parameters, and generating a tube hole distribution map.

5. The method of claim 4, wherein: The graphical rendering and interaction module is also used for providing interactive functions of point selection, deletion and invalid hole (13) marking for subsequent obstacle avoidance identification.

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