Aircraft pipeline sealing detection device and method based on thermal imaging technology

Abstract

The application discloses an aircraft pipeline sealing detection device and method based on thermal imaging technology, which comprises an air tightness test system, an oil tightness test system, a thermal imaging detection assembly and a control system. The air tightness test system realizes rapid determination of the pipeline leakage point area range by introducing heated high-pressure gas into the guide pipe assembly and cooperating with the thermal imaging detection assembly. The oil tightness test system realizes key detection of the air tightness test marked leakage point area by introducing heated high-pressure hydraulic oil into the guide pipe assembly and cooperating with the thermal imaging detection assembly, thereby realizing determination of the accurate position of the pipeline leakage point. The thermal imaging detection assembly drives the thermal image sensor to move along a predetermined track through multiple sets of three-axis assemblies, and detects infrared radiation emitted by the high-temperature gas or high-temperature hydraulic oil. The control system is used for real-time driving and monitoring of the working state of the detection device. The application realizes accurate determination of the pipeline leakage point through air tightness and oil tightness double tests in combination with the thermal imaging technology.

Description

Technical Field

[0001] This invention belongs to the field of aerospace manufacturing engineering and aircraft assembly inspection technology, specifically relating to an aircraft pipeline sealing inspection device and method based on thermal imaging technology. Background Technology

[0002] Aircraft piping is an indispensable part of an aircraft. It primarily transports various media, such as fuel, hydraulic fluid, and lubricating oil. These media are crucial for the normal operation of the aircraft, ensuring the proper functioning of the engine, hydraulic system, and cooling system, guaranteeing the normal operation of all components and ensuring aircraft safety. The sealing performance of aircraft piping is paramount; seal failure can lead to serious safety problems, such as fuel leaks and hydraulic system failures, which can jeopardize flight safety and cause significant losses. Effective sealing of aircraft piping helps maintain stable system parameters such as pressure and temperature, prevents contaminants from entering the system, ensures normal system operation and extends service life, thereby improving the overall performance of the aircraft.

[0003] Aircraft fuel tanks contain numerous and complex pipelines. During the installation of pipeline components, it is necessary to conduct sealing checks on fuel lines, hydraulic lines, and other pipelines. Currently, the sealing of aircraft pipelines is mainly tested twice using two methods: air tightness testing and oil tightness testing. 1) In the air tightness test, operators use a mechanical air tightness testing machine to pressurize the pipeline with air and maintain the pressure. During the pressure holding period, inspectors check for leaks by touch and hearing. 2) In the oil tightness test, operators use a mechanical oil tightness testing machine to input high-pressure hydraulic oil into the pipeline and maintain the pressure. During the pressure holding period, inspectors visually inspect the pipeline surface to identify leaks and simultaneously wipe suspected leak points with a paper towel. If oil stains remain on the paper towel, it indicates an oil leak. Due to the large number and complexity of pipelines within the fuel tank, checking for leaks places a significant workload on inspectors. Visual inspection is prone to errors and subjectivity, resulting in low accuracy and efficiency in current pipeline sealing tests, making the methods ineffective. Furthermore, mechanical airtightness and oiltightness testing benches are difficult to operate and labor-intensive, impacting production efficiency.

[0004] To achieve rapid and accurate detection of aircraft fuel tank pipeline sealing, improve the installation efficiency of fuel tank pipelines in production units, and ensure fuel tank pipeline sealing, it is urgent to design an intelligent aircraft pipeline sealing detection device and its usage method to improve the accuracy and efficiency of fuel tank pipeline leak detection. Summary of the Invention

[0005] The purpose of this invention is to provide an aircraft pipeline sealing inspection device and method based on thermal imaging technology, aiming to solve the problems of high labor intensity, low inspection accuracy, and low inspection efficiency in the existing aircraft fuel tank pipeline sealing inspection using manual mechanical test benches.

[0006] To achieve the above objectives, the present invention employs the following technical solution: Aircraft pipeline sealing test device based on thermal imaging technology includes an airtightness test system, an oil tightness test system, and thermal imaging test components. The airtightness testing system includes an airtightness testing pipeline, on which are sequentially installed a compressed gas cylinder, a first gas solenoid valve, a gas filter, a gas pressure reducing valve, a gas pressure sensor, a gas check valve, a gas heating device, a second gas solenoid valve, an inlet, an outlet, and a solenoid exhaust valve. The conduit assembly to be tested is detachably connected between the inlet and the outlet. The airtightness testing system is used to introduce heated high-pressure gas into the conduit assembly, and in conjunction with a thermal imaging detection component, detect the location of gas leaks to quickly determine the extent of leaks in the pipeline. The oil tightness test system includes an oil tightness test pipeline, on which a hydraulic oil tank, a liquid filter, a first liquid solenoid valve, an electric pump, an overflow valve, a liquid pressure reducing valve, a pressure sensor, a liquid check valve, a liquid heating device, a third liquid solenoid valve, an oil inlet, an oil outlet, and a second liquid solenoid valve are sequentially installed. The conduit assembly to be tested is detachably connected between the oil inlet and the oil outlet. The oil tightness test system is used to introduce heated high-pressure hydraulic oil into the conduit assembly and, in conjunction with a thermal imaging detection component, detect the location of hydraulic oil leaks to accurately determine the location of pipeline leaks. The thermal imaging detection component includes a triaxial assembly that corresponds one-to-one with the detection area inside the conduit assembly. Each triaxial assembly is equipped with a thermal image sensor for thermal imaging scanning and detection of the conduit assembly. The location of the pipeline leak is determined by detecting the infrared radiation emitted by the leaking high-temperature gas and high-temperature hydraulic oil.

[0007] Furthermore, it also includes a control system; The control system includes an electrical control box, a first monitor, a second monitor, a display screen, and multiple control switches. The electrical control box contains a power supply module, a control module, and a drive module, which are used to drive and monitor the working status of the detection device in real time, control the switching of each solenoid valve, collect data from each sensor, drive the movement of the three-axis assembly, and display the detection results.

[0008] Furthermore, in the airtightness testing system, a compressed gas cylinder is used to store high-pressure gas as the gas source for the airtightness test; a first gas solenoid valve is controlled to open or close via a first gas switch; a gas filter is used to filter impurities in the high-pressure gas; a gas pressure reducing valve is used to adjust the gas pressure to the specified test pressure value; a gas pressure sensor is used to monitor the gas pressure value in the airtightness test pipeline in real time, and the gas pressure value is displayed through a first monitor; a gas check valve is used to prevent gas backflow in the airtightness test pipeline; a gas heating device is equipped with a heating wire inside, which can heat the gas to a predetermined temperature; a temperature sensor is installed on the gas heating device to monitor the internal temperature of the gas heating device in real time, stopping heating when the predetermined temperature is exceeded, and continuing heating when the predetermined temperature is not reached; a second gas solenoid valve is controlled to open or close via a second gas switch, and after opening, the high-temperature gas that has reached the predetermined temperature enters the conduit assembly to be tested through the inlet; a solenoid exhaust valve is controlled to open or close via a third gas switch, and after the airtightness test is completed, the solenoid exhaust valve is opened, and the gas is discharged from the outlet.

[0009] Furthermore, in the oil tightness test system, the hydraulic oil tank is used to store hydraulic oil as the oil source for the oil tightness test, and also to recover the hydraulic oil after the test; the liquid filter is used to filter the output hydraulic oil; the first liquid solenoid valve is controlled to open or close via a first liquid switch; the electric pump is started via an electric pump switch, used to draw hydraulic oil from the hydraulic oil tank and output pressurized hydraulic oil; the overflow valve is connected to the return oil line of the hydraulic oil tank, and automatically opens when the hydraulic oil pressure output by the electric pump is too high, allowing excess hydraulic oil to flow back to the hydraulic oil tank; the liquid pressure reducing valve is used to adjust the hydraulic oil pressure to the specified test pressure value; and the pressure sensor is used to monitor the pressure value in the oil tightness test pipeline in real time, and the pressure value is determined by... The second monitor displays: a liquid check valve to prevent hydraulic oil backflow; a liquid heating device to heat the hydraulic oil to a predetermined temperature; a liquid temperature sensor is installed on the liquid heating device to monitor the internal temperature of the liquid heating device in real time, stopping heating when the predetermined temperature is exceeded and continuing heating when the predetermined temperature is not reached; a third liquid solenoid valve is opened or closed by a third liquid switch, and after opening, the high-temperature hydraulic oil that has reached the predetermined temperature enters the conduit assembly through the inlet; a second liquid solenoid valve is opened or closed by a second liquid switch, and after the oil tightness test is completed, the second liquid solenoid valve is opened, and the hydraulic oil is discharged from the outlet, filtered again by the liquid filter, and then flows back to the hydraulic oil tank.

[0010] Furthermore, the thermal imaging detection assembly also includes a frame and a base; the frame is fixed on the base, and multiple sets of triaxial components are mounted on the frame; the triaxial components include an X-axis slide, an L-shaped angle bracket, a Y-axis slide, a Z-axis slide, a thermal image sensor, and a U-shaped angle bracket; the X-axis slide is fixed on the frame; the L-shaped angle bracket is fixed on the slider of the X-axis slide; the Y-axis slide is connected to the L-shaped angle bracket; the Z-axis slide is fixed on the slider of the Y-axis slide; one end of the U-shaped angle bracket is fixed on the slider of the Z-axis slide, and the other end is connected to the thermal image sensor; through the coordinated movement of the X-axis slide, Y-axis slide, and Z-axis slide, the thermal image sensor can achieve triaxial motion detection according to a predetermined trajectory.

[0011] Furthermore, the electrical control box is fixed on the test bench; the power supply module supplies power to the testing device; the control module receives the monitoring values ​​from each sensor, as well as the operation signals from the execution key, reset key, and each switch; it can drive the opening and closing of each solenoid valve; it outputs the monitoring values ​​from the air pressure sensor and air temperature sensor to the first monitor for display, and outputs the monitoring values ​​from the pressure sensor and liquid temperature sensor to the second monitor for display; it outputs the thermal imaging images collected by the thermal image sensor to the display screen; and it outputs commands to the drive module to control the movement of the three-axis assembly.

[0012] The aircraft piping sealing inspection method based on thermal imaging technology, utilizing the aforementioned device, includes the following steps: Step 1: Turn on the power switch. The control module, drive module, test bench, and triaxial assembly will be powered on and started. Press the reset button to return the triaxial assembly to its initial position. All electrical valves should be closed before the test. Step two: Connect the air inlet and outlet to the starting and ending ends of the conduit assembly to be tested; open the first gas solenoid valve, and the high-pressure gas in the compressed gas cylinder, after being filtered by the gas filter and regulated by the gas pressure reducing valve, is heated to the predetermined temperature by the gas heating device; open the second gas solenoid valve, and the high-temperature gas enters the conduit assembly through the air inlet; press the execute button, and the drive module drives the three-axis assembly to move the thermal image sensor according to the programmed trajectory to perform thermal imaging scanning detection on the conduit assembly; when a pipeline leak is found, the thermal image sensor collects the leak information and determines the area of ​​the pipeline leak, marks the leak area, and displays the leak information on the display screen; after the detection is completed, open the electromagnetic exhaust valve, and the gas is discharged from the outlet; press the reset button to return the three-axis assembly to the initial position; Step 3: Connect the oil inlet and outlet to the starting and ending ends of the conduit assembly; open the first liquid solenoid valve, start the electric pump, and the hydraulic oil in the hydraulic tank is filtered by the liquid filter, regulated by the liquid pressure reducing valve, and then heated to the predetermined temperature by the liquid heating device. Open the third liquid solenoid valve, and the high-temperature hydraulic oil enters the conduit assembly through the oil inlet; press the execute button, and the thermal image sensor moves to the leak point area marked in the airtightness test in Step 2, slowly scanning and detecting the leaking high-temperature hydraulic oil to determine the precise location of the pipeline leak and display the leak location information on the display screen; after detecting the marked leak point area, press the execute button again to perform supplementary detection on other areas; after the detection is completed, open the second liquid solenoid valve, and the hydraulic oil is discharged from the oil outlet, flows back to the hydraulic tank through the liquid filter, and the power switch is turned off.

[0013] Furthermore, prior to step one, the following also includes: The thermal imaging detection component is placed at a preset position directly in front of the conduit component, so that each triaxial component corresponds to a detection area.

[0014] Furthermore, in step two, the gas pressure reducing valve adjusts the gas pressure to... The gas heating device heats the gas to a predetermined temperature. .

[0015] Furthermore, in step three, the liquid pressure reducing valve adjusts the hydraulic oil pressure to... The liquid heating device heats the hydraulic oil to a predetermined temperature. .

[0016] Compared with the prior art, the present invention has the following technical features: 1. The test bench can perform both airtightness and oiltightness tests. During the test, operators only need to follow the operating procedures to press switches and observe data, reducing workload and minimizing test errors caused by human error. It also improves product installation efficiency.

[0017] 2. By conducting dual tests for air tightness and oil tightness, combined with thermal imaging technology, leaks in the fuel tank pipeline can be detected accurately, avoiding detection errors caused by manual inspection and improving detection accuracy and efficiency.

[0018] 3. An intelligent control system is adopted, which can drive and monitor the working status of the test bench in real time, making it convenient for operators and inspectors to observe and judge.

[0019] 4. This invention can accurately eliminate pipeline leaks, prevent pipeline leaks, ensure the normal operation of the engine, hydraulic system and cooling system, and guarantee the normal function of each component and aircraft safety. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the airtightness test principle; Figure 2 This is a schematic diagram illustrating the principle of the oil tightness test; Figure 3 This is a schematic diagram of the airtightness and oiltightness test bench; Figure 4 This is a schematic diagram of the thermal imaging detection component; Figure 5 This is a schematic diagram of a three-axis assembly structure; Figure 6 This is a schematic diagram of the inside of the control box; Figure 7 This is a schematic diagram of the fuel tank inspection area; Figure 8 This is a schematic diagram of the detection process.

[0021] Explanation of reference numerals in the attached diagram: 1-Compressed gas cylinder, 2-First gas solenoid valve, 3-Gas filter, 4-Gas pressure reducing valve, 5-Pressure sensor, 6-Gas check valve, 7-Temperature sensor, 8-Gas heating device, 9-Second gas solenoid valve, 10-Inlet, 11-Outlet, 12-Solenoid exhaust valve, 13-Hydraulic oil tank, 14-Liquid filter, 15-First liquid solenoid valve, 16-Relief valve, 17-Pressure sensor, 18-Liquid temperature sensor, 19-Liquid heating device, 20-Oil inlet, 21-Oil outlet, 22-Second liquid solenoid valve, 23-Third liquid solenoid valve, 24-Liquid check valve, 25-Liquid pressure reducing valve, 26-Electric pump, 27-First monitor, 28-Actuation key. 29-Power switch, 30-First gas switch, 31-Second gas switch, 32-Third gas switch, 33-Hex bolt, 34-Electric control box, 35-Test bench, 36-Display screen, 37-Electric pump switch, 38-First liquid switch, 39-Second liquid switch, 40-Third liquid switch, 41-Reset button, 42-Second monitor, 43-Triaxial assembly, 44-Washer, 45-Nut, 46-Frame, 47-Base, 48-X-axis slide, 49-M5 screw, 50-L-shaped angle bracket, 51-Y-axis slide, 52-Z-axis slide, 53-Thermal image sensor, 54-M2.5 screw, 55-U-shaped angle bracket, 56-Power module, 57-Control module, 58-Drive module. Detailed Implementation

[0022] Currently, the sealing tests of aircraft fuel tank pipelines are mainly conducted manually using mechanical valves and switches to perform airtightness and oil tightness tests, which is a cumbersome process. Leakage inspection of pipelines primarily relies on human sight, hearing, and touch; however, the results are susceptible to subjective human factors, and the accuracy and efficiency of the inspections are low.

[0023] This invention provides an aircraft pipeline sealing performance testing device and method based on thermal imaging technology. By designing an intelligent airtightness and oil tightness test bench, a dual testing process for pipeline airtightness and oil tightness is achieved, and thermal imaging technology enables accurate identification of pipeline leaks. The method employs an intelligent control system that can drive and monitor the test bench's operating status in real time. A testing method for fixing the thermal imaging system is also designed. This testing method enables efficient and high-precision testing of aircraft fuel tank pipeline sealing performance, avoiding errors caused by manual inspection, achieving rapid and accurate confirmation of aircraft pipeline sealing performance, and improving production efficiency.

[0024] like Figures 1 to 6 As shown, the present invention provides an aircraft pipeline sealing test device based on thermal imaging technology, which mainly includes four parts: an airtightness test system, an oil tightness test system, a thermal imaging detection component, and a control system.

[0025] (a) Air tightness test system.

[0026] An airtightness testing system is used to introduce heated, high-pressure gas into the ductwork assemblies of an aircraft and use thermal imaging technology to detect the location of gas leaks, enabling rapid determination of the extent of leaks in the pipeline. For example... Figure 1 As shown, the airtightness testing system includes an airtightness testing pipeline, on which are sequentially arranged a compressed gas cylinder 1, a first gas solenoid valve 2, a gas filter 3, a gas pressure reducing valve 4, a gas pressure sensor 5, a gas check valve 6, a gas heating device 8, a second gas solenoid valve 9, an air inlet 10, an air outlet 11, and a solenoid exhaust valve 12; the conduit assembly to be tested (such as an aircraft fuel tank conduit assembly) is detachably connected between the air inlet 10 and the air outlet 11, wherein: Compressed gas cylinder 1 is used to store high-pressure gas as the gas source for the airtightness test; a first gas solenoid valve 2 is located at the outlet of compressed gas cylinder 1 and is controlled to open or close by a first gas switch 30; after the first gas solenoid valve 2 is opened, the high-pressure gas released from compressed gas cylinder 1 enters gas filter 3 to filter impurities in the high-pressure gas; a gas pressure reducing valve 4 is located after gas filter 3 to adjust the gas pressure to the gas pressure value specified for the test, which is [value missing] in this embodiment. It can also protect the pipeline; the pressure sensor 5 is used to monitor the pressure value in the airtight test pipeline in real time, and the pressure value is displayed by the first monitor 27; the gas check valve 6 is set after the pressure sensor 5 to prevent the gas in the airtight test pipeline from flowing back and avoid damage to the equipment caused by backflow.

[0027] Gas heating device 8 is installed after gas check valve 6, and contains heating wire to heat the gas to a predetermined temperature. A temperature sensor 7 is installed on the gas heating device 8 to monitor the internal temperature of the gas heating device 8 in real time. If the temperature exceeds the preset temperature, heating stops; if the preset temperature is not reached, heating continues until the gas reaches the preset temperature. A second gas solenoid valve 9 is installed on the airtightness test pipeline after the gas heating device 8, which is controlled to open or close by a second gas switch 31. The inlet 10 is connected to the starting end of the conduit assembly, and the outlet 11 is connected to the ending end of the conduit assembly. After the second gas solenoid valve 9 is opened, the high-temperature gas that has reached the preset temperature enters the conduit assembly to be tested through the inlet 10, and an airtightness test is performed with the cooperation of the thermal imaging detection component. An electromagnetic exhaust valve 12 is installed after the outlet 11 and is controlled to open or close by a third gas switch 32. After the airtightness test of the conduit assembly is completed, the electromagnetic exhaust valve 12 is opened, and the gas is discharged from the outlet 11.

[0028] (ii) Oil tightness test system.

[0029] The oil tightness testing system is used to introduce heated, high-pressure hydraulic oil into the aircraft's piping assemblies. Thermal imaging technology is then used to detect the location of hydraulic oil leaks, enabling precise determination of the leak's location. For example... Figure 2 As shown, the system includes an oil tightness test pipeline, on which a hydraulic oil tank 13, a liquid filter 14, a first liquid solenoid valve 15, an electric pump 26, an overflow valve 16, a liquid pressure reducing valve 25, a pressure sensor 17, a liquid check valve 24, a liquid heating device 19, a third liquid solenoid valve 23, an oil inlet 20, an oil outlet 21, and a second liquid solenoid valve 22 are sequentially arranged. The conduit assembly to be tested is detachably connected between the oil inlet 20 and the oil outlet 21, wherein: The hydraulic oil tank 13 is used to store hydraulic oil, serving as the oil source for the oil tightness test, and also for recovering the hydraulic oil after the test. A liquid filter 14 is located at the outlet of the hydraulic oil tank 13 to filter the output hydraulic oil, ensuring that the hydraulic oil in the oil tightness test pipeline is free of impurities. Following the liquid filter 14 is a first liquid solenoid valve 15, controlled by a first liquid switch 38, used to control the flow of hydraulic oil and regulate its flow rate. Following the first liquid solenoid valve 15 is an electric pump 26, activated by an electric pump switch 37, used to provide driving force for the flow of hydraulic oil, capable of drawing pressurized hydraulic oil from the hydraulic oil tank 13. An overflow valve 16 is installed in the oil tightness test pipeline following the electric pump 26, connected to the return oil pipeline of the hydraulic oil tank 13. When the hydraulic oil pressure output by the electric pump 26 is too high, the overflow valve 16 automatically opens, allowing excess hydraulic oil to flow back to the hydraulic oil tank 13, protecting the hydraulic components from damage.

[0030] The liquid pressure reducing valve 25 is located after the relief valve 16 and is used to adjust the hydraulic oil pressure to the specified test pressure value. In this embodiment, the pressure value is... Pressure sensor 17 is located after liquid pressure reducing valve 25 and is used to monitor the pressure value in the oil tightness test pipeline in real time. The pressure value is displayed by the second monitor 42. Liquid check valve 24 is located after pressure sensor 17 and is used to prevent hydraulic oil backflow and avoid equipment damage caused by backflow.

[0031] The liquid heating device 19 is located downstream of the liquid check valve 24 and is used to heat the hydraulic oil to a predetermined temperature. A temperature sensor 18 is installed on the liquid heating device 19 to monitor the internal temperature of the liquid heating device 19 in real time: if the predetermined temperature value is exceeded, heating stops; if the predetermined temperature value is not reached, heating continues until the hydraulic oil reaches the predetermined temperature. A third liquid solenoid valve 23, controlled by a third liquid switch 40, is installed at the outlet of the liquid heating device 19; the inlet 20 is connected to the starting end of the conduit assembly, and the outlet 21 is connected to the ending end of the conduit assembly. After the third liquid solenoid valve 23 is opened, the high-temperature hydraulic oil that has reached the predetermined temperature enters the conduit assembly through the inlet 20, and an oil tightness test is performed with the assistance of a thermal imaging detection component.

[0032] The second liquid solenoid valve 22 is located after the oil outlet 21 and is controlled to open or close by the second liquid switch 39. After the oil tightness test of the conduit assembly is completed, the second liquid solenoid valve 22 is opened, and the hydraulic oil is discharged from the oil outlet 21, filtered again by the liquid filter 14, and then flows back to the hydraulic oil tank 13.

[0033] (III) Thermal imaging detection component.

[0034] Thermal imaging detection components are used in conjunction with airtightness testing systems and oiltightness testing systems to perform thermal imaging scanning detection on aircraft duct assemblies. By detecting the infrared radiation emitted by leaking high-temperature gas or hydraulic oil, the location of leaks on the duct assemblies can be determined. Figure 4 , Figure 5 As shown, the component includes a frame 46, a base 47, and several sets of triaxial components 43.

[0035] Frame 46 is fixed to base 47 by four hexagonal bolts 33. Six sets of triaxial assemblies 43 are installed on frame 46, each set corresponding to a detection area inside the conduit assembly to be tested; for example... Figure 4 As shown, in this embodiment, there is a row of three-axis components 43 on the upper and lower parts of the frame 45, with three sets in each row; it should be noted that the structure of the frame 46, the number of three-axis components 43 and the fixed position are adjusted according to the actual detection requirements so that the three-axis components 43 can completely cover all areas to be detected.

[0036] The three-axis assembly 43 includes an X-axis slide 48, M5 screws 49, an L-shaped angle bracket 50, a Y-axis slide 51, a Z-axis slide 52, a thermal image sensor 53, M2.5 screws 54, and a U-shaped angle bracket 55. The X-axis slide 48 is fixed to the frame 46 by two hexagonal bolts 33, two washers 44, and two nuts 45. The L-shaped angle bracket 50 is fixed to the slider of the X-axis slide 48 by four M5 screws 49. The Y-axis slide 51 is connected to the L-shaped angle bracket 55 by four M5 screws 49. Angle piece 50 is connected; Z-axis slide 52 is fixed to the slider of Y-axis slide 51 by four M5 screws 49; one end of U-shaped angle piece 55 is fixed to the slider of Z-axis slide 52 by two M5 screws 49, and the other end is connected to thermal image sensor 53 by two M2.5 screws 54; through the coordinated movement of X-axis slide 48, Y-axis slide 51 and Z-axis slide 52 in the three-axis assembly 43, thermal image sensor 53 can realize three-axis movement detection according to a predetermined trajectory.

[0037] The thermal image sensor 53 performs thermal imaging detection based on the infrared radiation emitted by the object. In the airtightness test, if there is a leak in the pipeline of the conduit assembly, the leaking high-temperature gas diffuses in the air. The thermal image sensor 53 can detect the leaking high-temperature gas and display the thermal image on the display screen 36. Since the leaking high-temperature gas will diffuse in the air, the area of ​​the pipeline leak can be quickly determined through the thermal image. The thermal image sensor 53 will mark the area of ​​the leak to prepare for subsequent oil tightness test detection.

[0038] During the oil tightness test, the thermal image sensor 53 focuses on slowly detecting the leaking area marked by the air tightness test. By detecting the leaking high-temperature hydraulic oil, the thermal image is displayed on the display screen 36 to determine the precise location of the leak. After focusing on detecting the leaking area marked by the air tightness test, the thermal image sensor 53 will also detect other areas to prevent missed detections in the air tightness test.

[0039] (iv) Control system.

[0040] The control system is used to drive and monitor the working status of the detection device in real time, control the switching of various solenoid valves, collect data from various sensors, drive the movement of the three-axis assembly 43, and display the detection results; such as Figure 3 , Figure 6 As shown, the control system includes an electrical control box 34, a first monitor 27, a second monitor 42, a display screen 36, and various control switches.

[0041] The electrical control box 34 is fixed to the test bench 35 by two hexagonal bolts 33. Inside, there is a power module 56, a control module 57, and a drive module 58. The power module 56 supplies power to the various electric components of the testing device, including the first gas solenoid valve 2, the second gas solenoid valve 9, the electromagnetic exhaust valve 12, the first liquid solenoid valve 15, the second liquid solenoid valve 22, the third liquid solenoid valve 23, the display screen 36, the first monitor 27, the second monitor 42, the air pressure sensor 5, the air temperature sensor 7, the pressure sensor 17, the liquid temperature sensor 18, the gas heating device 8, the liquid heating device 19, the electric pump 26, the X-axis slide 48, the Y-axis slide 51, the Z-axis slide 52, the control module 57, and the drive module 58.

[0042] The control module 57 is used to receive monitoring values ​​from the pressure sensor 5, temperature sensor 7, pressure sensor 17, and liquid temperature sensor 18, as well as operation signals from the execution key 28, reset key 41, first gas switch 30, second gas switch 31, third gas switch 32, electric pump switch 37, first liquid switch 38, second liquid switch 39, and third liquid switch 40; it can drive the opening and closing of the first gas solenoid valve 2, second gas solenoid valve 9, electromagnetic exhaust valve 12, first liquid solenoid valve 15, second liquid solenoid valve 22, and third liquid solenoid valve 23; it outputs the monitoring values ​​of the pressure sensor 5 and temperature sensor 7 to the first monitor 27 for display, and outputs the monitoring values ​​of the pressure sensor 17 and liquid temperature sensor 18 to the second monitor 42 for display; it outputs the thermal imaging image collected by the thermal image sensor 53 to the display screen 36 for display; and it outputs commands to the drive module 58 to control the movement of the X-axis slide 48, Y-axis slide 51, and Z-axis slide 52 in the three-axis assembly 43.

[0043] The drive module 58 is used to control the movement of the X-axis slide 48, Y-axis slide 51 and Z-axis slide 52 in the three-axis assembly 43; the drive module 58 is switched on and off by the execution key 28, thereby driving the three-axis assembly 43 to move according to the trajectory set in the program.

[0044] The first monitor 27 displays the monitoring values ​​of the barometric pressure sensor 5 and the air temperature sensor 7. The second monitor 42 displays the monitoring values ​​of the pressure sensor 17 and the liquid temperature sensor 18. The display screen 36 displays graphic information from the thermal imaging.

[0045] The functions of each control switch are as follows: Power switch 29 is the main switch of the control system. Pressing it powers on and starts the control module 57, drive module 58, test bench 35, and triaxial assembly 43. Reset button 41 can reset the system program. When a special situation requires re-performing thermal imaging detection, pressing reset button 41 will return the triaxial assembly 43 to its initial position. First gas switch 30, second gas switch 31, and third gas switch 32 control the opening and closing of first gas solenoid valve 2, second gas solenoid valve 9, and solenoid exhaust valve 12, respectively, through control module 57. Electric pump switch 37 controls the opening and closing of electric pump 26. First liquid switch 38, second liquid switch 39, and third liquid switch 40 control the opening and closing of first liquid solenoid valve 15, second liquid solenoid valve 22, and third liquid solenoid valve 23, respectively, through control module 57. Execute button 28 is used to control the opening and closing of drive module 58, thereby driving the triaxial assembly 43 to move.

[0046] An air inlet 10, an air outlet 11, an oil inlet 20, and an oil outlet 21 are mounted on a test bench 35. The air inlet 10 connects to the starting end of the conduit assembly; during the airtightness test, heated gas enters the starting end of the conduit assembly through the air inlet 10. The air outlet 11 connects to the ending end of the conduit assembly; gas is discharged through the solenoid exhaust valve 12 after passing through the air outlet 11. The oil inlet 20 connects to the starting end of the conduit assembly; during the oiltightness test, heated hydraulic oil enters the starting end of the conduit assembly through the oil inlet 20. The oil outlet 21 connects to the ending end of the conduit assembly; hydraulic oil returns to the hydraulic oil tank 13 after passing through the second liquid solenoid valve 22 and the liquid filter 14 after passing through the oil outlet 21.

[0047] Based on the above system, this invention also provides a method for detecting the sealing performance of aircraft pipelines based on thermal imaging technology. For the conduit assembly to be tested (such as a fuel tank conduit assembly), the test procedure requires both airtightness and oil tightness tests to determine pipeline leaks. Figure 4 , Figure 7 , Figure 8 As shown, before the test, the thermal imaging detection component is placed in a preset position directly in front of the conduit assembly. In this embodiment, the conduit assembly is divided into six detection areas, each of which is filled with conduits. Correspondingly, this solution sets up six sets of triaxial components 43, each set of triaxial components 43 is used for the sealing test of the conduits in one detection area, and is one-to-one with the detection area.

[0048] Step 1: Preparation before the experiment.

[0049] Turn on the power switch 29 to power on and start the control module 57, drive module 58, test bench 35, and triaxial assembly 43; press the reset button 41 to return the triaxial assembly 43 to its initial position for testing. Before the test, all electrical valves inside the test bench 35 are closed.

[0050] Step two, airtightness test.

[0051] Connect the air inlet 10 and air outlet 11 to the starting and ending ends of the conduit assembly to be tested; press the first gas switch 30 to open the first gas solenoid valve 2, and the high-pressure gas in the compressed gas cylinder 1 passes through the gas filter 3 and is adjusted to the test pressure value through the gas pressure reducing valve 4. The air pressure sensor 5 monitors the air pressure value in real time and displays it through the first monitor 27; after passing through the gas check valve 6, the gas enters the gas heating device 8, which begins to heat the gas. The air temperature sensor 7 monitors the internal temperature of the gas heating device 8 in real time until the temperature reaches the predetermined temperature. Heating stops, and the temperature value is displayed on the first monitor 27.

[0052] Press the second gas switch 31 to open the second gas solenoid valve 9. High-temperature gas enters the duct assembly through the inlet 10 and then begins thermal imaging detection. Press the execute key 28 to start the drive module 58, which drives the X-axis slide 48, Y-axis slide 51, and Z-axis slide 52 in the three-axis assembly 43 to move according to the trajectory set in the program (such as scanning by row or by column). The six thermal image sensors 53 begin to perform thermal imaging scanning detection on each detection area.

[0053] When a pipeline leak is detected in a certain area, high-temperature gas will leak out. The thermal image sensor 53 (integrated processing unit) will collect the leak information and quickly determine the area of ​​the pipeline leak. The thermal image sensor 53 will mark the area of ​​the leak to prepare for subsequent oil tightness test and display the leak information on the display screen 36 in the form of an image for easy viewing by inspectors.

[0054] Press the third gas switch 32 to open the electromagnetic exhaust valve 12, and the gas will be discharged through the outlet 11. After the airtightness test is completed, press the reset button 41 again, and the triaxial assembly 43 will return to the initial position.

[0055] Step 3: Oil tightness test.

[0056] Connect the oil inlet 20 and oil outlet 21 to the starting and ending ends of the conduit assembly; press the first liquid switch 38 and the electric pump switch 37 to open the first liquid solenoid valve 15 and start the electric pump 26. The hydraulic oil in the hydraulic oil tank 13 passes through the electric pump 26 and outputs high-pressure hydraulic oil; when the hydraulic oil pressure output by the electric pump 26 is too high, the overflow valve 16 automatically opens to return the excess hydraulic oil to the hydraulic oil tank 13; the hydraulic oil pressure is adjusted to the test-specified pressure value through the liquid pressure reducing valve 25. Pressure sensor 17 monitors the pressure value in real time and displays it on the second monitor 42; hydraulic oil enters the liquid heating device 19 through the liquid check valve 24 to start heating until the temperature reaches the predetermined temperature. Heating stops, and the liquid temperature sensor 18 monitors the temperature in real time and displays it on the second monitor 42.

[0057] Press the third liquid switch 40 to open the third liquid solenoid valve 23, and high-temperature hydraulic oil enters the conduit assembly through the inlet 20. Thermal imaging detection begins. Press the execute key 28, and the thermal image sensor 53, via the triaxial assembly 43, moves to the leak area marked in the airtightness test in step two, slowly scanning the leaking high-temperature hydraulic oil to determine the precise location of the pipeline leak. The specific leak location information is then displayed on the screen 36 in image form, facilitating the inspector's accurate identification of the leak. After detecting the leak area in the airtightness test, press the execute key 28 again, and the triaxial assembly 43 will re-detect other areas to prevent missed leaks in the airtightness test.

[0058] Press the second liquid switch 39 to open the second liquid solenoid valve 22. The hydraulic oil returns to the hydraulic oil tank 13 through the oil outlet 21 and the liquid filter 14, and the oil tightness test is completed. Turn off the power switch 29 and tidy up the equipment.

[0059] After the above airtightness and oiltightness tests and thermal imaging detection are completed, the inspectors finally determine the location of the pipeline leak, and the operators troubleshoot the leak.

[0060] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An aircraft pipeline sealing inspection device based on thermal imaging technology, characterized in that, This includes an airtightness testing system, an oil tightness testing system, and thermal imaging detection components; The airtightness test system includes an airtightness test pipeline, on which a compressed gas cylinder (1), a first gas solenoid valve (2), a gas filter (3), a gas pressure reducing valve (4), a gas pressure sensor (5), a gas check valve (6), a gas heating device (8), a second gas solenoid valve (9), an air inlet (10), an air outlet (11), and an electromagnetic exhaust valve (12) are sequentially installed. The conduit assembly to be tested is detachably connected between the air inlet (10) and the air outlet (11). The airtightness test system is used to introduce heated high-pressure gas into the conduit assembly and, in conjunction with a thermal imaging detection component, detect the gas leak location to achieve rapid determination of the leak area of ​​the pipeline. The oil tightness test system includes an oil tightness test pipeline, on which a hydraulic oil tank (13), a liquid filter (14), a first liquid solenoid valve (15), an electric pump (26), an overflow valve (16), a liquid pressure reducing valve (25), a pressure sensor (17), a liquid check valve (24), a liquid heating device (19), a third liquid solenoid valve (23), an oil inlet (20), an oil outlet (21), and a second liquid solenoid valve (22) are sequentially installed. The conduit assembly to be tested is detachably connected between the oil inlet (20) and the oil outlet (21). The oil tightness test system is used to introduce heated high-pressure hydraulic oil into the conduit assembly and, in conjunction with a thermal imaging detection component, detect the location of hydraulic oil leakage to achieve precise determination of the location of pipeline leaks. The thermal imaging detection assembly includes a triaxial assembly (43) that corresponds one-to-one with the detection area inside the conduit assembly. Each triaxial assembly (43) is equipped with a thermal image sensor (53) for thermal imaging scanning detection of the conduit assembly. The location of the pipeline leak is determined by detecting the infrared radiation emitted by the leaking high-temperature gas and high-temperature hydraulic oil.

2. The aircraft pipeline sealing inspection device based on thermal imaging technology according to claim 1, characterized in that, It also includes the control system; The control system includes an electrical control box (34), a first monitor (27), a second monitor (42), a display screen (36), and multiple control switches. The electrical control box (34) is equipped with a power supply module (56), a control module (57), and a drive module (58) for real-time driving and monitoring of the working status of the detection device, controlling the switches of each solenoid valve, collecting data from each sensor, driving the movement of the three-axis assembly (43), and displaying the detection results.

3. The aircraft pipeline sealing inspection device based on thermal imaging technology according to claim 1, characterized in that, In the airtightness test system, a compressed gas cylinder (1) is used to store high-pressure gas as the gas source for the airtightness test; a first gas solenoid valve (2) is controlled to open or close by a first gas switch (30); a gas filter (3) is used to filter impurities in the high-pressure gas; a gas pressure reducing valve (4) is used to adjust the gas pressure to the test pressure value; a gas pressure sensor (5) is used to monitor the gas pressure value in the airtightness test pipeline in real time, and the gas pressure value is displayed by a first monitor (27); a gas check valve (6) is used to prevent gas backflow in the airtightness test pipeline; and a gas heating device (8) is equipped with a heating wire to heat the gas. Heat to the predetermined temperature; A temperature sensor (7) is installed on the gas heating device (8) to monitor the internal temperature of the gas heating device (8) in real time. When the predetermined temperature is exceeded, heating stops, and heating continues when the predetermined temperature is not reached; The second gas solenoid valve (9) is controlled to open or close by the second gas switch (31). After opening, the high temperature gas that has reached the predetermined temperature enters the inside of the conduit assembly to be tested through the air inlet (10); The electromagnetic exhaust valve (12) is controlled to open or close by the third gas switch (32). After the air tightness test is completed, the electromagnetic exhaust valve (12) is opened, and the gas is discharged from the air outlet (11).

4. The aircraft pipeline sealing inspection device based on thermal imaging technology according to claim 1, characterized in that, In the oil tightness test system, the hydraulic oil tank (13) is used to store hydraulic oil as the oil source for the oil tightness test and to recover the hydraulic oil after the test; the liquid filter is used to filter the output hydraulic oil; the first liquid solenoid valve (15) is controlled to open or close by the first liquid switch (38); the electric pump (26) is started by the electric pump switch (37) to draw hydraulic oil from the hydraulic oil tank (13) and output pressurized hydraulic oil; the overflow valve (16) is connected to the return oil line of the hydraulic oil tank (13) and automatically opens when the hydraulic oil pressure output by the electric pump (26) is too high, so that the excess hydraulic oil flows back to the hydraulic oil tank (13); the liquid pressure reducing valve (25) is used to adjust the hydraulic oil pressure to the test specified pressure value; the pressure sensor (17) is used to monitor the pressure value in the oil tightness test line in real time, and the pressure value is monitored by the second monitor (42). The display shows that the liquid check valve (24) is used to prevent hydraulic oil backflow; the liquid heating device (19) is used to heat the hydraulic oil to a predetermined temperature; a liquid temperature sensor (18) is installed on the liquid heating device (19) to monitor the internal temperature of the liquid heating device (19) in real time, and stops heating when the predetermined temperature is exceeded, and continues heating when the predetermined temperature is not reached; the third liquid solenoid valve (23) is controlled to open or close by the third liquid switch (40), and the high-temperature hydraulic oil that has reached the predetermined temperature after opening enters the conduit assembly through the oil inlet (20); the second liquid solenoid valve (22) is controlled to open or close by the second liquid switch (39), and the second liquid solenoid valve (22) is opened after the oil tightness test is completed, and the hydraulic oil is discharged from the oil outlet (21), filtered again by the liquid filter (14) and then flows back to the hydraulic oil tank (13).

5. The aircraft pipeline sealing inspection device based on thermal imaging technology according to claim 1, characterized in that, The thermal imaging detection assembly also includes a frame (46) and a base (47); the frame (46) is fixed on the base (47), and multiple sets of triaxial components (43) are installed on the frame (46); the triaxial components (43) include an X-axis slide (48), an L-shaped angle bracket (50), a Y-axis slide (51), a Z-axis slide (52), a thermal image sensor (53), and a U-shaped angle bracket (55); the X-axis slide (48) is fixed on the frame (46); the L-shaped angle bracket (50) is fixed on the X-axis slide. The slider of the X-axis slide (48) is connected to the L-shaped angle (50); the Z-axis slide (52) is fixed on the slider of the Y-axis slide (51); one end of the U-shaped angle (55) is fixed on the slider of the Z-axis slide (52), and the other end is connected to the thermal image sensor (53); through the coordinated movement of the X-axis slide (48), the Y-axis slide (51) and the Z-axis slide (52), the thermal image sensor (53) can realize three-axis motion detection according to a predetermined trajectory.

6. The aircraft pipeline sealing inspection device based on thermal imaging technology according to claim 2, characterized in that, In the control system, the electrical control box (34) is fixed on the test bench (35); the power supply module (56) is used to power the detection device; the control module (57) is used to receive the monitoring values ​​of each sensor, as well as the operation signals of the execution key (28), the reset key (41), and each switch; it can drive the opening and closing of each solenoid valve; it outputs the monitoring values ​​of the air pressure sensor (5) and the air temperature sensor (7) to the first monitor (27) for display, and outputs the monitoring values ​​of the pressure sensor (17) and the liquid temperature sensor (18) to the second monitor (42) for display; it outputs the thermal imaging image collected by the thermal image sensor (53) to the display screen (36) for display; and it outputs commands to the drive module (58) to control the movement of the triaxial assembly (43).

7. A method for detecting the airtightness of aircraft pipelines based on thermal imaging technology, utilizing the apparatus of any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Turn on the power switch (29). The control module (57), drive module (58), test bench (35), and triaxial assembly (43) are powered on and started. Press the reset button (41) to return the triaxial assembly (43) to the initial position. Before the test, all electrical valves are closed. Step 2: Connect the inlet (10) and outlet (11) to the starting and ending ends of the conduit assembly to be tested; open the first gas solenoid valve (2), and the high-pressure gas in the compressed gas cylinder (1) is filtered by the gas filter (3) and regulated by the gas pressure reducing valve (4), and then heated to the predetermined temperature by the gas heating device (8). Open the second gas solenoid valve (9), and the high-temperature gas enters the conduit assembly through the inlet (10); press the execute key (28), and the drive module (58) drives the triaxial assembly (43) to move the thermal image sensor (53) according to the trajectory set in the program, and perform thermal imaging scanning detection on the conduit assembly; when a pipeline leak occurs, the thermal image sensor (53) collects the leakage information and determines the area of ​​the pipeline leak, marks the area of ​​the leak, and displays the leakage information on the display screen (36); after the detection is completed, open the electromagnetic exhaust valve (12), and the gas is discharged from the outlet (11). Press the reset key (41) to return the triaxial assembly (43) to the initial position; Step 3: Connect the oil inlet (20) and oil outlet (21) to the starting and ending ends of the conduit assembly; open the first liquid solenoid valve (15), start the electric pump (26), and the hydraulic oil in the hydraulic tank (13) is filtered by the liquid filter (14), regulated by the liquid pressure reducing valve (25), and heated to the predetermined temperature by the liquid heating device (19). Open the third liquid solenoid valve (23), and the high-temperature hydraulic oil enters the conduit assembly through the oil inlet (20); press the execution key (28), and the thermal image sensor (5) activates. 3) Move to the leak area marked in step two, slowly scan and detect the leaking high-temperature hydraulic oil, determine the precise location of the pipeline leak, and display the leak location information on the display screen (36); after detecting the marked leak area, press the execution key (28) again to perform supplementary detection on other areas; after the detection is completed, open the second liquid solenoid valve (22), the hydraulic oil is discharged from the oil outlet (21), flows back to the hydraulic oil tank (13) through the liquid filter (14), and the power switch (29) is turned off.

8. The aircraft pipeline sealing inspection method based on thermal imaging technology according to claim 7, characterized in that, Before step one, the following also applies: The thermal imaging detection component is placed at a preset position directly in front of the conduit component, so that each set of triaxial components (43) corresponds to a detection area.

9. The aircraft pipeline sealing inspection method based on thermal imaging technology according to claim 7, characterized in that, In step two, the gas pressure reducing valve (4) adjusts the gas pressure to... The gas heating device (8) heats the gas to a predetermined temperature. .

10. The aircraft pipeline sealing inspection method based on thermal imaging technology according to claim 7, characterized in that, In step three, the liquid pressure reducing valve (25) adjusts the hydraulic oil pressure to... The liquid heating device (19) heats the hydraulic oil to a predetermined temperature. .

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