Pneumatic control valve debugging device and method based on PLC

Abstract

The invention discloses a pneumatic control valve debugging device and debugging method based on a PLC. The debugging device comprises a movable mounting device, and the movable mounting device is provided with wheels; the PLC control module is mounted on the movable mounting device; the electric control box module is electrically connected with the PLC control module; the air source module is electrically connected with the electric control box and the PLC control module and used for providing an air source for the pneumatic control valve; the power supply module is electrically connected with the PLC control module, the electric cabinet module and the air source module, and is used for converting an external power supply into a power supply required by the PLC control module, the electric cabinet module and the air source module; the pneumatic control valve debugging device based on the PLC is provided with the air source system, meanwhile, the PLC serves as the core, air, electricity and signal systems needed by debugging of the pneumatic control valve are combined together, a complete debugging system is formed, the integrity of the debugging device is guaranteed, and the intelligent and automatic level of debugging of the pneumatic control valve is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of valve debugging, and in particular to a PLC-based pneumatic control valve debugging device and debugging method. Background Art

[0002] With the increasing automation of industrial production and the increasing precision requirements for production control, the installation and use of pneumatic control valves is increasing. Pneumatic control valves require precision adjustment before use and regular inspection during use. The typical conditions for commissioning a pneumatic control valve are: 1. The air source for the control valve is installed, the air source pressure and cleanliness meet the requirements, and the air source system is functioning properly. 2. The signal and feedback cables for the pneumatic control valve are connected and inspected to ensure proper signal transmission. 3. The PLC system is installed and the program is being debugged properly. These conditions are often achieved late in the project, leaving very limited time for pneumatic control valve commissioning, resulting in high pressure on commissioning personnel. This can sometimes affect the commissioning and production time of the entire system, hindering the overall project schedule. This is not adapted to the development of modern construction technology and actual needs, thus requiring more advanced commissioning equipment suitable for on-site installation.

[0003] In the prior art, the utility model patent with patent number ZL201821027903.9 discloses a portable intelligent valve debugging device and system, including a computer interface, a valve signal input interface, a valve data processing module, a valve control module, and a sensor assembly for measuring electric valves and pneumatic valves.

[0004] The invention patent with patent number ZL201510389303.1 discloses a portable valve debugging device, including a touch-screen human-machine interface, a PLC system, a relay group, a battery pack, and a power converter module. The output end of the battery pack is respectively connected to the power end of the touch-screen human-machine interface and the PLC system. The power converter module includes power converter No. 1 and power converter No. 2. The output end of the battery pack is respectively connected to the input end of power converter No. 1 and the input end of power converter No. 2. The signal output end of the touch-screen human-machine interface is connected to the signal input end of the PLC system. The signal output end of the PLC system is connected to the relay group. The PLC system controls the external valve through the relay group.

[0005] Both of the above-mentioned valve debugging devices have the problem of poor system integrity, lack of air source system, and inability to independently complete the debugging of pneumatic control valves, which needs further improvement. Summary of the Invention

[0006] The purpose of the present invention is to provide a PLC-based pneumatic control valve debugging device and debugging method, aiming to improve the problems of poor system integrity of existing valve debugging devices, lack of air source system, and inability to complete the debugging of pneumatic control valves completely and independently.

[0007] To achieve the above-mentioned object, according to one aspect of the present invention, there is provided a PLC-based pneumatic control valve debugging device, comprising a mobile installation device having wheels; and further comprising:

[0008] PLC control module;

[0009] The electric control box module is electrically connected to the PLC control module;

[0010] The air source module is electrically connected to the electric control box and the PLC control module and is used to provide air source for the pneumatic regulating valve;

[0011] The power module is electrically connected to the PLC control module, the electric control box module and the gas source module, and is used to convert the external power into the power required by the PLC control module, the electric control box module and the gas source module.

[0012] Furthermore, the mobile installation device also has an armrest and a wheel drive device, the power module includes a battery, the wheel drive device is electrically connected to the electric control box module, and the battery supplies power to the wheel drive device and the electric control box module.

[0013] Furthermore, the air source module includes an air compressor, an air tank and a connecting pipeline. The air compressor and the air tank are connected through the connecting pipeline. An air supply pipeline for connecting to a pneumatic regulating valve is installed at the exhaust interface of the air tank.

[0014] Furthermore, a pressure transmitter for detecting the internal air pressure of the gas storage tank is installed on the gas storage tank, the air compressor and the electric control box module are electrically connected, and the pressure transmitter and the PLC control module are electrically connected.

[0015] Furthermore, the PLC control module includes a PLC cabinet and an operating table. A PLC system is installed in the PLC cabinet. The PLC system includes a CPU module, an AI module, an AO module, a DO module and a DI module. A control computer is provided on the operating table. The control computer and the PLC system are electrically connected.

[0016] According to a second aspect of the present invention, the present invention provides a method for debugging a pneumatic control valve, which uses the above-mentioned PLC-based pneumatic control valve debugging device to debug the pneumatic control valve.

[0017] Further, the following steps are included:

[0018] S100, inputting the technical parameters and usage requirements of the pneumatic control valve into the PLC control module;

[0019] S200, input debugging points and generate a debugging plan;

[0020] S300, connect the air source module and the pneumatic control valve;

[0021] S400: Start the PLC-based pneumatic control valve debugging device to input compressed air into the pneumatic control valve;

[0022] S500, adjusting the control pressure input to the pneumatic control valve actuator to the pressure required for the valve to operate;

[0023] S600 and PLC control modules control the pneumatic control valve for debugging according to the debugging plan.

[0024] Furthermore, in the step S100, if the technical parameters of the pneumatic control valve do not meet the usage requirements, the PLC control module outputs an alarm message; in the step S200, the debugging points include the stroke rising stage points and the stroke falling stage points, and the stroke rising stage points include the 0% stroke point, 25% stroke point, 50% stroke point, 75% stroke point and 100% stroke point in sequence, and the stroke falling stage points include the 100% stroke point, 75% stroke point, 50% stroke point, 25% stroke point and 0% stroke point in sequence; in the step S600, after the debugging of one test point is completed, the debugging of the next test point is carried out.

[0025] Furthermore, in step S600, each time the PLC control module sends a signal to the pneumatic control valve, it measures the size of the signal received by the valve positioner of the pneumatic control valve, compares the difference between the measured value and the standard value, and if the difference exceeds the allowable range, finds the cause and adjusts it to the allowable range; if the difference is within the allowable range, measures and observes whether the action of the pneumatic control valve meets the requirements; if it does not meet the requirements, finds the cause and makes corrections; if it can meet the requirements, measures the position feedback signal of the pneumatic control valve; if the feedback value does not meet the requirements, adjusts the feedback of the valve positioner until it meets the requirements.

[0026] Furthermore, in step S600, whether the action of the pneumatic control valve meets the requirements includes: the pneumatic control valve operates smoothly without sticking or shaking during the action; after the PLC control module sends a control signal, the pneumatic control valve must complete the corresponding action within a specified time;

[0027] In step S600, after completing the debugging of one stroke rising stage point and one stroke descending stage point, multiple rechecking and debugging are performed, and each test point of the stroke rising stage point and the stroke descending stage point is repeatedly tested. If there is a point that does not meet the debugging requirements, re-debugging is performed until the valve action and feedback of each test point meet the requirements; after completing all debugging, a debugging record is generated and printed.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The present invention has an air source system and, with PLC as the core, combines the air, electricity and signal systems required for the debugging of the pneumatic control valve to form a complete debugging system, thereby ensuring the integrity of the debugging device and realizing the intelligent and automated level of the debugging of the pneumatic control valve.

[0030] 2. This invention uses computer technology to create a scientific and reasonable debugging experiment plan for pneumatic control valves, and can easily adjust the plan as needed. It also automatically measures, records, and judges, improving measurement accuracy, reducing human errors, reducing personnel input, reducing costs, and increasing test speed.

[0031] 3. After the single-point debugging is completed, the pneumatic control valve can continuously perform continuous experimental debugging according to the operation of the program, and can automatically record the experimental debugging results, automatically judge and give conclusions, automatically print experimental records, and draw experimental curves.

[0032] 4. The present invention can reduce the input of personnel and save labor costs when used on site. During the debugging process, the device and the pneumatic control valve can be observed and operated at any time, which facilitates timely detection and resolution of problems. It reduces the inconvenience of communication between on-site personnel and indoor personnel in traditional debugging methods and improves debugging efficiency.

[0033] 5. The present invention uses PLC for control, which allows debugging and testing of PLC programs during the debugging phase, enabling loop debugging and interlocking debugging, which is impossible with traditional debugging using simple signal generators. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a block diagram of the electrical control structure of the PLC-based pneumatic control valve debugging device provided in Example 1 of the present invention;

[0035] Figure 2 This is a schematic diagram of the module principle of the PLC-based pneumatic control valve debugging device provided in Example 1 of the present invention;

[0036] Figure 3This is a flowchart of the debugging method provided in Example 2 of the present invention.

[0037] Figure numerals: 1. air compressor; 2. PLC system; 3. pressure transmitter; 4. control computer; 5. pneumatic control valve feedback terminal; 6. pneumatic control valve signal terminal. DETAILED DESCRIPTION

[0038] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0039] The following is a further description with reference to the accompanying drawings and specific embodiments:

[0040] Example 1

[0041] This embodiment provides a PLC-based pneumatic control valve debugging device, such as Figure 1 and Figure 2 As shown, the debugging device includes a PLC control module, an electrical control box module, an air source module, and a power supply module, all of which are mounted on a mobile mounting device. The mobile mounting device comprises a frame with handrails at one or both ends and wheels at the bottom to facilitate movement of the entire debugging device. The mobile mounting device can be used with a mobile trolley equipped with multiple lifting rings, making it easy to transport using a lifting device such as an overhead crane in locations where wheeled movement is inconvenient.

[0042] like Figure 1 and Figure 2 As shown, the electrical control box module is electrically connected to the PLC control module. The air source module is electrically connected to the electrical control box and PLC control module, providing air for the pneumatic control valve. The power module is electrically connected to the PLC control module, the electrical control box module, and the air source module. The power module typically has 380V and 220V terminals for connecting to a 380V power source and a 220V power source, respectively. The power module also includes a power conversion device that converts external power into the power required by the PLC control module, the electrical control box module, and the air source module.

[0043] The electrical control box module serves as the debugging device's electrical control equipment and command executor. Its internal electrical design must meet the debugging device's control requirements. The module's electrical circuits, under the control of the PLC control module, implement electrical control of the corresponding equipment. Electrical control box modules come in a variety of different configurations, a typical example of which includes the control box body and relays, contactors, circuit breakers, transformers, current transformers, voltage transformers, voltmeters, ammeters, indicator lights, and control switches mounted within and on the walls.

[0044] In some exemplary embodiments, the mobile installation device also has a wheel drive device, the power module includes a battery, the wheel drive device is electrically connected to the electrical control box module, and the battery supplies power to the wheel drive device and the electrical control box module, thereby realizing the electric drive movement of the debugging device and reducing the labor intensity of manual pushing.

[0045] The PLC control module is the control center of the debugging device. The PLC control module includes a PLC cabinet and an operating table. Figure 2 As shown, a PLC system 2 is installed in a PLC cabinet. PLC system 2 includes a CPU module, an AI module, an AO module, a DO module, a DI module, and a PLC cabinet power supply. The CPU module is the core module of PLC system 2, responsible for managing and calculating PLC system 2, collecting and processing data, and issuing instructions according to program execution. The AO module is an analog output module, responsible for issuing analog control signals. The AI ​​module is an analog data acquisition module; for example, the feedback terminal 5 of the pneumatic control valve is electrically connected to the AI ​​module. The DO module is a digital output module, responsible for issuing digital control signals, and the DI module is a digital data acquisition module. The PLC cabinet power supply is responsible for converting external power to the power required by PLC system 2. A control computer 4 is installed on the operating console and is electrically connected to PLC system 2. Control computer 4 is an auxiliary device for PLC system 2, serving as the display and operating system for PLC system 2. It displays PLC data on the screen and the operating status of the debugging device on the screen. The system is operated intuitively on the screen, and programming and program modification of PLC system 2 are performed using a mouse and keyboard.

[0046] The air source module includes an air compressor 1, an air tank, and connecting pipes. The air compressor 1 and the air tank are connected through the connecting pipes to deliver compressed air to the air tank. The exhaust interface of the air tank is installed with an air supply pipe for connecting to the pneumatic control valve. When debugging the pneumatic control valve, the air tank is connected to the pneumatic control valve through the air supply pipe to supply air to the pneumatic control valve. The air tank is installed with a pressure transmitter 3 to detect the air pressure inside the air tank, such as Figure 2As shown, air compressor 1 is electrically connected to the electrical control box module, and pressure transmitter 3 is electrically connected to the PLC control module. Pressure transmitter 3 transmits the detected pressure value to PLC system 2. When the pressure value falls below the set value, PLC system 2 activates air compressor 1, increasing the pressure inside the air tank. When the pressure inside the air tank reaches the set upper pressure limit, PLC system 2 sends a signal to control air compressor 1 to stop. This ensures that the pressure inside the air tank is always within the set range, ensuring pressure stability during the commissioning of the pneumatic control valve.

[0047] Example 2

[0048] A method for debugging a pneumatic control valve utilizes the PLC-based pneumatic control valve debugging device provided in Example 1 to perform pneumatic control valve debugging. After the debugging device is installed and debugged, it can be moved or transported to the pneumatic control valve debugging site, connected to the pneumatic control valve, and debugged. Prior to debugging, a control computer 4 receives externally input design documents, design drawings, specifications, implemented standards, contract agreements, and other construction-related information, selecting necessary information such as the project name, instrument design, automation design, flow charts, control system schematics, and instrument installation layout diagrams.

[0049] Pneumatic control valves are promptly counted and updated upon arrival. The project, position number, specification, model, valve serial number, and storage location of each pneumatic control valve are recorded. A commissioning plan is developed based on the type, usage, and travel of each pneumatic control valve. This includes wiring principles, recording point selection, commissioning data curve drawing, judgment criteria, commissioning data comparison, commissioning results, commissioning record generation, and commissioning data storage.

[0050] like Figure 3 As shown, the debugging method specifically includes the following steps:

[0051] S100. Input the technical parameters and usage requirements of the pneumatic control valve into the PLC control module. The technical parameters of the pneumatic control valve include the nameplate information of the pneumatic control valve, which includes information such as valve type, nominal diameter, rated pressure, rated flow coefficient, actuator type and specifications. Input the obtained basic parameters into the preset debugging system database to establish a basic information file for the pneumatic control valve. By collecting and organizing the detailed basic parameters of the pneumatic control valve, an accurate reference basis can be provided for subsequent debugging work, ensuring that the debugging process is based on the correct valve characteristics. Pneumatic control valves of different types and specifications have different performance characteristics and applicable ranges. Accurate basic parameters help the debugging system more reasonably plan the debugging process and set debugging parameters. If the technical parameters of the pneumatic control valve do not meet the usage requirements, the PLC control module will output an alarm message and perform replacement and rectification. When the technical parameters of the pneumatic control valve meet the usage requirements, proceed to the next step.

[0052] S200. Input debugging points and generate a debugging plan. To ensure the comprehensiveness and accuracy of the debugging results, perform multi-point debugging. The debugging points include the stroke-up phase and the stroke-down phase, with five points selected for each phase. The stroke-up phase points include, in order, 0% stroke, 25% stroke, 50% stroke, 75% stroke, and 100% stroke. The stroke-down phase points include, in order, 100% stroke, 75% stroke, 50% stroke, 25% stroke, and 0% stroke.

[0053] S300: Connect the air source module and the pneumatic control valve so that the air storage tank of the air source module can provide compressed air to the pneumatic control valve.

[0054] S400: Start the PLC-based pneumatic control valve debugging device, control air compressor 1 to start and operate, and fill the air tank with compressed air at a pressure that meets the debugging requirements. Open the air source valve of the pneumatic control valve and input compressed air into the pneumatic control valve.

[0055] S500. Adjust the pressure adjustment knob of the valve positioner of the pneumatic control valve to adjust the control pressure input to the pneumatic control valve actuator to the pressure required for the valve to work.

[0056] This step is a key step to ensure the normal, stable and efficient operation of the pneumatic control valve and achieve precise control, which is mainly reflected in the following aspects:

[0057] The first is to ensure the normal operation of the valve: Pneumatic control valves rely on compressed air to provide power to drive the actuator, thereby realizing the opening, closing or adjustment of the valve opening. Pneumatic control valves of different types and specifications, as well as different working conditions, correspond to specific working pressure ranges. Only by adjusting the pressure to the appropriate value can the actuator generate sufficient driving torque to overcome the friction resistance and medium pressure inside the valve, ensuring that the valve can operate flexibly and accurately. If the pressure is insufficient, the actuator may not be able to drive the valve to the required opening, resulting in the valve not being adjusted in place, affecting the control of medium parameters such as flow and pressure; if the pressure is too high, it will cause excessive load on the actuator, valve sealing components, etc., accelerate component wear, and even damage the valve, shortening its service life.

[0058] Second, ensure regulation accuracy and stability: Accurate operating pressure is the foundation for precise adjustment of pneumatic control valves. Only under appropriate pressure can pneumatic control valves stably control flow within the set range according to process requirements, ensuring stable operation. If the pressure is unstable or does not meet the requirements, the valve opening adjustment will deviate.

[0059] Third, it facilitates adaptation to actual working conditions: In actual industrial production, different process flows, piping systems, and media characteristics have different requirements for the working pressure of pneumatic control valves. Adjusting the pressure to the value required by the valve is to make the debugged pneumatic control valve better adapt to specific working conditions.

[0060] The S600 and PLC control modules control the pneumatic control valves for debugging according to the debugging plan. After debugging one test point, the next test point is debugged. Each time the PLC control module sends a signal to the pneumatic control valve, the debugger measures the signal received by the pneumatic control valve positioner and compares the measured value with the standard value. If the difference exceeds the allowable range, the cause is identified and the positioner is adjusted to within the allowable range. The allowable range is defined as the ratio of the difference to the standard value of 5% or less. If the difference is within the allowable range, the pneumatic control valve is measured and observed to ensure that the valve operates as expected. If not, the cause is identified and corrected.

[0061] Whether the action of the pneumatic control valve meets the requirements includes:

[0062] 1. Operational stability requirements: Pneumatic control valves must operate smoothly, without sticking or jitter, during operation. They must operate smoothly and evenly, both during the rising phase (from closed to open) and the falling phase (from open to closed). If sticking occurs, the valve may not respond to control signals in a timely manner, affecting the regulation effect. Jitter can cause fluctuations in media parameters and even damage internal valve components, shortening the valve's service life. Stable operation performance is the basis for ensuring the reliable operation of pneumatic control valves.

[0063] 2. Response speed requirements: After the PLC control module issues a control signal, the pneumatic control valve must complete the corresponding action within the specified time to meet the actual operating conditions and the demand for timely adjustment. In some rapidly changing production processes, the pneumatic control valve must respond quickly to signal changes and adjust the opening in a timely manner. Failure to do so may cause system pressure imbalance and pose a safety hazard. The response speed requirements of the pneumatic control valve vary under different operating conditions and need to be set according to the specific production process and application scenario.

[0064] If the pneumatic control valve's action meets the requirements, the tester should measure the valve's position feedback signal. If the feedback value does not meet the requirements, the valve positioner's feedback should be adjusted until it meets the requirements. The position feedback signal is the position feedback signal of the pneumatic control valve's spool or stem. It is important for ensuring the valve accurately executes control commands and ensuring stable system operation.

[0065] The detailed measurement process and instructions are as follows:

[0066] 1. Signal Source: Pneumatic control valves use actuators to drive the valve core or stem, changing the valve opening and adjusting parameters such as medium flow and pressure. A position feedback device (such as a displacement sensor or potentiometer) is installed on a component linked to the valve core or stem. When the valve core or stem moves, the position feedback device converts its displacement into an electrical signal (such as a voltage or current signal) or other transmittable signal form. This is the position feedback signal, which reflects the current position of the valve core or stem, i.e., the actual valve opening, in real time.

[0067] 2. Core function: On the one hand, the position feedback signal is used to form a closed-loop control system. After the PLC control module sends a control signal to drive the valve to move, it is necessary to use the position feedback signal to confirm whether the valve has reached the expected opening. If there is a deviation between the actual position and the target position, the control device can adjust the control strategy in time according to the feedback signal, and send the control signal again to adjust the valve, thereby achieving precise control of the valve opening and ensuring that the medium parameters are stable within the process requirements. On the other hand, the position feedback signal helps to monitor the operating status of the valve. By continuously observing the changes in the feedback signal, it can be determined whether the valve has faults such as stuck or abnormal displacement. For example, if the feedback signal does not change for a long time or changes abnormally, it may mean that the valve is stuck and needs to be inspected and repaired in time.

[0068] 3. Specific measurement method: There are many common measurement methods, such as potentiometer measurement method, displacement sensor measurement method, etc. When using a potentiometer position feedback device, its rotation angle or sliding displacement is associated with the displacement of the valve core or valve stem. As the valve core or valve stem moves, the resistance value of the potentiometer changes. By measuring the voltage across the potentiometer, the corresponding valve position can be converted according to Ohm's law. When using a displacement sensor (such as a linear displacement sensor) for measurement, the sensor is directly connected to the valve core or valve stem. The sensor will convert the linear displacement of the valve core or valve stem into a corresponding electrical signal output based on its own working principle (such as magnetostriction, inductive, etc.). By reading and analyzing the electrical signal, the valve position information can be obtained.

[0069] In addition, some intelligent pneumatic control valves can also directly transmit position feedback signals in digital form to the control system through digital communication protocols (such as HART, Modbus, etc.), facilitating data processing and analysis.

[0070] In this embodiment, five points are selected for debugging in the stroke-up phase and the stroke-down phase, respectively. The stroke-up phase points include, in sequence, the 0% stroke point, the 25% stroke point, the 50% stroke point, the 75% stroke point, and the 100% stroke point, and the stroke-down phase points include, in sequence, the 100% stroke point, the 75% stroke point, the 50% stroke point, the 25% stroke point, and the 0% stroke point. After completing debugging of the stroke-up phase points and the stroke-down phase points, multiple rechecks and debugging are required. Repeated testing is performed on each test point in the stroke-up phase and the stroke-down phase. If any point does not meet the debugging requirements, re-debugging is performed until the valve action and feedback at each test point meet the requirements.

[0071] During the commissioning and operation of pneumatic control valves, the position feedback signal is closely related to the stroke. The position feedback signal is a quantitative reflection of the stroke status and provides a key basis for the precise control and status monitoring of the pneumatic control valve, which is specifically reflected in the following aspects:

[0072] First, it reflects the stroke position in real time: The stroke of a pneumatic control valve refers to the range of displacement of the valve core or valve stem from the fully closed position to the fully open position, and the position feedback signal converts this displacement change into an electrical signal or other transmittable signal. For example, when the valve core is in the fully closed position, the corresponding position feedback signal may be a 4mA current signal (taking the common 4-20mA signal as an example); as the valve core gradually opens and the stroke increases, the position feedback signal will also increase linearly according to a certain corresponding relationship. When the valve core reaches the fully open position, the position feedback signal becomes 20mA. In this way, the position feedback signal can accurately reflect the current stroke position of the pneumatic control valve in real time, allowing the control system and operator to understand the valve opening status at any time.

[0073] The second is to ensure stroke control accuracy: In a closed-loop control system, the PLC control module sends a control signal to the pneumatic control valve to set the target stroke position. The position feedback signal continuously feeds back the actual stroke position of the valve to the control device, forming a feedback loop. If there is a deviation between the actual stroke and the target stroke, the control device will adjust the output signal based on the difference between the position feedback signal and the target signal, and adjust the valve until the actual stroke reaches the target stroke position, thereby ensuring high-precision valve stroke control. For example, during the flow regulation process, by continuously comparing the position feedback signal and the target signal, the valve opening can be accurately fine-tuned to stabilize the medium flow at the set value.

[0074] The third is to monitor abnormal stroke conditions: The position feedback signal can also be used to monitor abnormal stroke conditions of pneumatic control valves. Under normal circumstances, there is a fixed correspondence between the position feedback signal and the stroke. If during operation, the position feedback signal experiences sudden changes, fluctuations, or fails to follow the stroke changes, it may indicate problems such as valve jamming, component damage, or feedback device failure. For example, when the valve core is stuck and cannot move normally due to impurities, the stroke stops changing, but the control signal is still being output. At this time, the deviation between the position feedback signal and the control signal will continue to increase. The system can then promptly issue an alarm and take appropriate measures to prevent the fault from expanding.

[0075] Fourth, assisting with stroke calibration and commissioning: During the commissioning process of a pneumatic control valve, stroke calibration is required to ensure that the actual valve stroke is consistent with the theoretical stroke. Position feedback signals play a crucial role in this process. Commissioning personnel can determine stroke accuracy by comparing the position feedback signal with the standard signal corresponding to the theoretical stroke. If any deviation exists, adjustments can be made to the valve positioner and feedback device to ensure that the correspondence between the position feedback signal and stroke meets the requirements, thus ensuring control accuracy and reliability during subsequent valve operation.

[0076] After all the debugging is completed, the debugging record is generated and printed. After the debugging of one pneumatic control valve is completed, the debugging device is moved to the vicinity of the next pneumatic control valve to debug the next pneumatic control valve.

[0077] In summary, the present invention provides a PLC-based pneumatic control valve debugging device, which has an air source system and, with the PLC as its core, integrates the gas, electrical, and signal systems required for pneumatic control valve debugging to form a complete debugging system. This ensures the integrity of the debugging device and achieves intelligent and automated debugging of pneumatic control valves. The present invention uses computer technology to scientifically and rationally plan debugging experiments for the debugging of pneumatic control valves, and can conveniently adjust the plan as needed. It also automatically measures, records, and judges. This improves measurement accuracy, reduces human errors, reduces personnel input, reduces costs, and increases testing speed. After single-point debugging is completed, the present invention can continuously perform continuous experimental debugging of the pneumatic control valve according to the operation of the program, and can automatically record the experimental debugging results, automatically judge and draw conclusions, automatically print experimental records, and draw experimental curves. When used on-site, the present invention can reduce personnel input and save labor costs. During the debugging process, the device and pneumatic control valve can be observed and operated at any time, making it easy to identify and address problems in a timely manner. This reduces the inconvenience of communication between on-site and in-house personnel (the traditional method is that a person on site debugs the pneumatic control valve, and someone in the operation room operates a computer to send signals), reduces communication misunderstandings, and improves debugging efficiency. In addition, the present invention uses a PLC for control, which allows the PLC program to be debugged and tested during the debugging phase, completes loop debugging, and allows for interlocking debugging. This is impossible with traditional debugging using simple signal generators.

[0078] The above is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A PLC-based pneumatic control valve debugging device, characterized in that: The invention comprises a mobile installation device having wheels; and further comprising: PLC control module; The electric control box module is electrically connected to the PLC control module; The air source module is electrically connected to the electric control box and the PLC control module and is used to provide air source for the pneumatic regulating valve; The power module is electrically connected to the PLC control module, the electric control box module and the gas source module, and is used to convert the external power into the power required by the PLC control module, the electric control box module and the gas source module.

2. A PLC-based pneumatic control valve debugging device according to claim 1, characterized in that: The mobile installation device also has an armrest and a wheel drive device, the power module includes a battery, the wheel drive device is electrically connected to the electric control box module, and the battery supplies power to the wheel drive device and the electric control box module.

3. The PLC-based pneumatic control valve debugging device according to claim 1 is characterized in that: The air source module comprises an air compressor (1), an air storage tank and a connecting pipeline. The air compressor (1) and the air storage tank are connected via the connecting pipeline. An air supply pipeline for connecting to a pneumatic regulating valve is installed at the exhaust interface of the air storage tank.

4. A PLC-based pneumatic control valve debugging device according to claim 3, characterized in that: The gas storage tank is equipped with a pressure transmitter (3) for detecting the internal air pressure of the gas storage tank. The air compressor (1) is electrically connected to the electric control box module, and the pressure transmitter (3) is electrically connected to the PLC control module.

5. The PLC-based pneumatic control valve debugging device according to claim 1 is characterized in that: The PLC control module includes a PLC cabinet and an operating console. A PLC system (2) is installed in the PLC cabinet. The PLC system (2) includes a CPU module, an AI module, an AO module, a DO module, and a DI module. A control computer (4) is provided on the operating console. The control computer (4) and the PLC system (2) are electrically connected.

6. A method for debugging a pneumatic control valve, characterized in that: The pneumatic control valve is debugged using the PLC-based pneumatic control valve debugging device as described in any one of claims 1 to 5.

7. The method for debugging a pneumatic control valve according to claim 6, characterized in that: The steps include: S100, inputting the technical parameters and usage requirements of the pneumatic control valve into the PLC control module; S200, input debugging points and generate a debugging plan; S300, connect the air source module and the pneumatic control valve; S400: Start the PLC-based pneumatic control valve debugging device to input compressed air into the pneumatic control valve; S500, adjusting the control pressure input to the pneumatic control valve actuator to the pressure required for the valve to operate; S600 and PLC control modules control the pneumatic control valve for debugging according to the debugging plan.

8. The method for debugging a pneumatic control valve according to claim 7, characterized in that: In the step S100, if the technical parameters of the pneumatic control valve do not meet the usage requirements, the PLC control module outputs an alarm message; in the step S200, the debugging points include the stroke rising stage points and the stroke falling stage points, and the stroke rising stage points include the 0% stroke point, 25% stroke point, 50% stroke point, 75% stroke point and 100% stroke point in sequence, and the stroke falling stage points include the 100% stroke point, 75% stroke point, 50% stroke point, 25% stroke point and 0% stroke point in sequence; in the step S600, after the debugging of one test point is completed, the debugging of the next test point is carried out.

9. The method for debugging a pneumatic control valve according to claim 8, characterized in that: In step S600, each time the PLC control module sends a signal to the pneumatic control valve, it measures the size of the signal received by the valve positioner of the pneumatic control valve, compares the difference between the measured value and the standard value, and if the difference exceeds the allowable range, finds the cause and adjusts it to the allowable range; if the difference is within the allowable range, measures and observes whether the action of the pneumatic control valve meets the requirements; if not, finds the cause and makes corrections; if it meets the requirements, measures the position feedback signal of the pneumatic control valve; if the feedback value does not meet the requirements, adjusts the feedback of the valve positioner until it meets the requirements.

10. The method for debugging a pneumatic control valve according to claim 9, characterized in that: In step S600, whether the action of the pneumatic control valve meets the requirements includes: The pneumatic control valve operates smoothly without any sticking or jittering during operation. After the PLC control module sends a control signal, the pneumatic control valve must complete the corresponding action within the specified time. In step S600, after completing the debugging of the stroke ascending stage point and the stroke descending stage point, multiple rechecking and debugging are performed, and each test point of the stroke ascending stage point and the stroke descending stage point is repeatedly tested. If there is a point that does not meet the debugging requirements, the debugging is repeated until the valve action and feedback of each test point meet the requirements; After all debugging is completed, a debugging record is generated and printed.

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