An air pressure control device for detecting the sealing of aircraft fuel tanks in extreme climate environments

Abstract

The present application belongs to the technical field of aircraft fuel tank sealing detection in extreme climate environments, and specifically relates to an air charging control device for aircraft fuel tank sealing detection in extreme climate environments. The device can withstand the extreme climate environment in a climate laboratory. When conducting a fuel tank sealing test on an aircraft wing in an extreme climate environment, the device can be arranged near the wing with the fuel tank. After the fuel tank is fully immersed in extreme climate environments such as low temperature, high temperature, and solar radiation, the fuel tank can be inflated and exhausted according to the pressure spectrum, thereby accurately and reliably completing the fuel tank pressurization, pressure maintenance, and pressure relief.

Description

Technical Field

[0001] The present application belongs to the technical field of fuel tank seal detection for aircraft in extreme climate environments, and specifically relates to an air pressurization control device for fuel tank seal detection for aircraft in extreme climate environments. Background Art

[0002] The wing box section of modern large aircraft has a large internal space, and the wing box space is often used to arrange fuel tanks. The sealing performance of the fuel tank has a significant impact on the safe operation of the aircraft. Fuel leakage will affect the structural integrity of the aircraft. Minor leaks will increase maintenance work and costs. Major leaks can also cause fires or loss of control of the aircraft. Therefore, the aircraft structure should be designed with meticulous sealing design, good structural sealing processes, and appropriate sealants. Because aircraft operations often encounter extreme climate environments such as low temperatures, high temperatures, and solar radiation, the sealing processes and sealants used in the fuel tanks are required to be able to withstand the highest and lowest fuel temperatures and ambient temperatures that may be encountered in actual use. Within the storage and operating temperature ranges, the sealing process will not fail, and the sealant should not crack or lose viscosity, which may cause leakage in the tank or reduce its service life.

[0003] To verify the sealing performance of fuel tanks, they were usually placed in low-temperature and high-temperature environmental chambers for immersion. Air was then pressurized inside the tanks for a certain period of time. The tanks were then inspected for leaks, deformation, and to determine whether their airtightness met the design and usage requirements. However, during actual aircraft use, it was discovered that because the fuel tanks were placed in the wings of the aircraft, after the aircraft as a whole was immersed in extreme climate environments such as low temperature, high temperature, and solar radiation, the temperature environment faced by the fuel tanks inside the wings was lower or higher than the temperature when the tanks were directly exposed to the extreme climate environments. Therefore, to more accurately verify the airtightness of the fuel tanks, the entire wing with the fuel tanks is now placed in a climate laboratory, where the aircraft wings are immersed in low-temperature, high-temperature, and solar radiation environments. The fuel tanks are then pressurized with air using an air pressurization device to test their sealing properties.

[0004] Previous verification methods involved immersing the fuel tank in an environmental chamber, with the air pressure control device placed outside the chamber. However, when conducting fuel tank seal testing in a climate laboratory, the entire wing with the fuel tank is placed in the climate laboratory, and the air pressure control device needs to be placed next to the wing. The reasons for this arrangement are: first, to reduce the distance between the pressure sensor and the fuel tank, thereby improving the accuracy of internal tank pressure detection; and second, when the fuel tank pressure exceeds the limit, the closer the exhaust pipe and control device are to the fuel tank, the faster the exhaust speed, ensuring the safety of the fuel tank. Therefore, the air pressure control device that was previously placed outside the environmental chamber could not withstand extreme environments such as high temperature, low temperature, and solar radiation when used in a climate laboratory. The air intake pipe was not treated with low dew point air dehumidification, which could easily cause condensation, ice, freezing, and leakage in the low-temperature environment of the fuel tank. At the same time, the protection measures for over-limit fuel tank pressure were single, and could not guarantee the smooth implementation of fuel tank seal testing in extreme climate environments.

[0005] This application is proposed in view of the above-mentioned technical defects. Summary of the Invention

[0006] The purpose of this application is to provide an air pressure control device for detecting the seal of an aircraft fuel tank in an extreme climate environment, so as to overcome or alleviate at least one of the technical defects of the known ones.

[0007] The technical solution of this application is:

[0008] An air pressure control device for detecting the seal of an aircraft fuel tank in an extreme climate environment includes an inflation cabinet, an exhaust cabinet, an air cooling and diffuser device for the inflation cabinet, an electric heater for the inflation cabinet, an air cooling and diffuser device for the exhaust cabinet, an electric heater for the exhaust cabinet, an air source access pipeline, an inflation branch, an exhaust pipeline, a slope control exhaust branch, a switch control exhaust branch, a manually controlled exhaust branch, and an air supply branch for a pneumatic valve;

[0009] The inflation cabinet and exhaust cabinet are installed in the climate laboratory, close to the wing with the fuel tank in the climate laboratory; the inflation cabinet air cooling diffuser and inflation cabinet electric heater are installed in the inflation cabinet, and the exhaust cabinet air cooling diffuser and exhaust cabinet electric heater are installed in the exhaust cabinet;

[0010] The air source access pipeline is set in the inflation cabinet, and the inlet passes through the inflation cabinet and is connected to the compressed air source;

[0011] The inflation branch is set in the inflation cabinet, the inlet is connected to the gas source access pipeline outlet, and the outlet is connected to the oil tank. It is equipped with an inflation control pressure reducing valve, an inflation control pneumatic switch valve, and an inflation control pneumatic regulating valve;

[0012] The exhaust pipe is set in the exhaust cabinet, and the inlet is connected to the oil tank;

[0013] The slope control exhaust branch is set in the exhaust cabinet, with the inlet connected to the exhaust pipe outlet, and the outlet passes through the exhaust cabinet, on which the oil tank pressure transmitter and the slope control exhaust pneumatic regulating valve are installed;

[0014] The switch-controlled exhaust branch is set in the exhaust cabinet, the inlet is connected to the exhaust pipe outlet, and the outlet is connected to the slope-controlled exhaust branch, on which an exhaust control pneumatic switch valve is set;

[0015] The manually controlled exhaust branch is set in the exhaust cabinet, with the inlet connected to the exhaust pipe outlet, and the outlet connected to the slope controlled exhaust branch, on which an exhaust control manual valve is set;

[0016] The pneumatic valve air supply branch is set in the inflation cabinet, the inlet is connected to the outlet of the air source access pipeline, the outlet passes through the inflation cabinet and extends into the exhaust cabinet, and is provided with an air branch control pressure reducing valve. It is connected to the inflation cabinet air cooling diffuser and the exhaust cabinet air cooling diffuser through a bypass. The bypass connecting the inflation cabinet air cooling diffuser and the exhaust cabinet air cooling diffuser is provided with an inflation cabinet air cooling diffuser control pneumatic switch valve and an exhaust cabinet air cooling diffuser control pneumatic switch valve.

[0017] According to at least one embodiment of the present application, in the above-mentioned extreme climate environment aircraft tank seal detection air charging control device, a dryer and an air source pressure indicating pressure gauge are provided on the air source access pipeline.

[0018] According to at least one embodiment of the present application, in the above-mentioned extreme climate environment aircraft tank seal detection air pressure control device, an inflation branch is also provided with an inflation control manual valve, an inflation control pneumatic regulating valve, an inflation branch indicating pressure gauge, and an inflation branch pressure transmitter.

[0019] According to at least one embodiment of the present application, in the above-mentioned extreme climate environment aircraft fuel tank seal detection air charging control device, a fuel tank pressure indicating pressure gauge is further provided on the slope control exhaust branch.

[0020] According to at least one embodiment of the present application, in the above-mentioned extreme climate environment aircraft tank seal detection air pressurization control device, the pneumatic valve air supply branch is connected to the inflation control pneumatic switch valve, the inflation control pneumatic regulating valve, the slope control exhaust pneumatic regulating valve, the exhaust control pneumatic switch valve, the inflation cabinet air cooling diffuser control pneumatic switch valve, and the exhaust cabinet air cooling diffuser control pneumatic switch valve through a small branch.

[0021] This application has at least the following beneficial technical effects:

[0022] Provided is an air charging control device for testing the sealing of aircraft fuel tanks in extreme climate environments. The device can withstand the extreme climate environments in climate laboratories. When conducting sealing tests on aircraft wing fuel tanks in extreme climate environments, the device can be arranged near the wing with the fuel tank. After the fuel tank has been fully immersed in extreme climate environments such as low temperature, high temperature, and solar radiation, the device can inflate and exhaust the fuel tank according to the pressure spectrum, accurately and reliably completing the fuel tank pressurization, pressure maintenance, and pressure relief. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 2 is a schematic diagram of an air pressure control device for detecting a fuel tank seal in an extreme climate environment provided by an embodiment of the present application;

[0024] in:

[0025] 1-Inflatable cabinet; 2-Exhaust cabinet; 3-Wing fuel tank with fuel tank; 4-Climate laboratory; 5-Inflatable cabinet air cooling and diffusion device; 6-Inflatable cabinet electric heater; 7-Exhaust cabinet air cooling and diffusion device; 8-Exhaust cabinet electric heater; 9-Air source access pipeline; 10-Dryer; 11-Air source pressure indicating pressure gauge; 12-Pneumatic valve air supply branch control manual valve; 13-Filter; 14-Pneumatic valve air supply branch control pressure reducing valve; 15-Pneumatic valve air supply branch indicating pressure gauge; 16-Pneumatic valve air supply branch pressure transmitter; 17-Pneumatic valve air supply branch; 18-Inflation control manual valve; 19-Inflation control pressure reducing valve Valve; 20-Inflation control pneumatic switch valve; 21-Inflation control pneumatic regulating valve; 22-Inflation branch indicating pressure gauge; 23-Inflation branch pressure transmitter; 24-Oil tank pressure indicating pressure gauge; 25-Oil tank pressure transmitter; 26-Slope control exhaust pneumatic regulating valve; 27-Exhaust control pneumatic switch valve; 28-Exhaust control manual valve; 29-Slope control exhaust branch; 30-Inflation cabinet air-cooled diffuser control pneumatic switch valve; 31-Exhaust cabinet air-cooled diffuser control pneumatic switch valve; 32-Inflation branch; 33-Exhaust pipeline; 34-Switch control exhaust branch; 35-Manual control exhaust branch.

[0026] In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. In addition, the drawings are only used for illustrative purposes and should not be understood as limiting this application. DETAILED DESCRIPTION

[0027] To make the technical solution and its advantages of this application more clear, the technical solution of this application will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described here are only some of the embodiments of this application and are only used to explain this application, not to limit this application. It should be noted that for ease of description, only the parts relevant to this application are shown in the accompanying drawings, and other relevant parts can refer to the general design.

[0028] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application should have the usual meanings understood by those skilled in the art in the field to which this application belongs. The words indicating orientation used in the description of this application are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "include" used in the description of this application means that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.

[0029] In addition, it should be noted that, unless otherwise clearly stipulated and limited, the words "installation", "connection" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Technical personnel in the field can understand its specific meaning in this application according to the specific circumstances.

[0030] An air pressure control device for detecting the sealing of an aircraft fuel tank in an extreme climate environment, such as Figure 1 As shown, it includes an inflation cabinet 1, an exhaust cabinet 2, an inflation cabinet air-cooling diffuser 5, an inflation cabinet electric heater 6, an exhaust cabinet air-cooling diffuser 7, an exhaust cabinet electric heater 8, an air source access pipeline 9, an inflation branch 32, an exhaust pipeline 33, a slope-controlled exhaust branch 29, a switch-controlled exhaust branch 34, a manually-controlled exhaust branch 35, and a pneumatic valve air supply branch 17.

[0031] The inflation cabinet 1 and the exhaust cabinet 2 are set up in the climate laboratory 4, close to the wing 3 with the fuel tank in the climate laboratory 4.

[0032] The air-cooling diffuser 5 and the electric heater 6 of the inflation cabinet are arranged in the inflation cabinet 1 , and the air-cooling diffuser 7 and the electric heater 8 of the exhaust cabinet are arranged in the exhaust cabinet 2 .

[0033] The gas source access pipeline 9 is set in the inflation cabinet 1. The inlet passes through the inflation cabinet 1 to connect to the compressed air source, and can also further pass through the climate laboratory 4 to connect to the compressed air source. A dryer 10 and a gas source pressure indicating pressure gauge 11 are arranged on it in sequence.

[0034] The inflation branch 32 is arranged in the inflation cabinet 1, the inlet is connected to the outlet of the gas source access pipeline 9, and the outlet is connected to the oil tank. The inflation control manual valve 18, the inflation control pressure reducing valve 19, the inflation control pneumatic switch valve 20, the inflation control pneumatic regulating valve 21, the inflation branch indicating pressure gauge 22, and the inflation branch pressure transmitter 23 are arranged on it in sequence.

[0035] The exhaust pipe 33 is provided in the exhaust cabinet 2, and the inlet is connected to the oil tank.

[0036] The slope control exhaust branch 29 is set in the exhaust cabinet 2, the inlet is connected to the outlet of the exhaust pipe 33, the outlet passes through the exhaust cabinet 2, and can also further pass through the climate laboratory 4. The oil tank pressure indicating pressure gauge 24, the oil tank pressure transmitter 25, and the slope control exhaust pneumatic regulating valve 26 are arranged on it in sequence.

[0037] The switch-controlled exhaust branch 34 is arranged in the exhaust cabinet 2, with its inlet connected to the outlet of the exhaust pipe 33, and its outlet connected to the slope-controlled exhaust branch 29, on which the exhaust-controlled pneumatic switch valve 27 is arranged.

[0038] The manually controlled exhaust branch 35 is provided in the exhaust cabinet 2 , with its inlet connected to the outlet of the exhaust pipe 33 , and its outlet connected to the slope controlled exhaust branch 29 , on which an exhaust control manual valve 28 is provided.

[0039] The pneumatic valve air supply branch 17 is arranged in the inflation cabinet 1, with the inlet connected to the outlet of the air source access pipeline 9, and the outlet passes through the inflation cabinet 1 and extends into the exhaust cabinet 2. The pneumatic valve air supply branch control manual valve 12, the filter 13, the pneumatic valve air supply branch control pressure reducing valve 14, the pneumatic valve air supply branch indicating pressure gauge 15, and the pneumatic valve air supply branch pressure transmitter 16 are arranged on it in sequence. It is connected to the inflation cabinet air cooling diffuser 5 and the exhaust cabinet air cooling diffuser 7 through a bypass. The bypass connecting the inflation cabinet air cooling diffuser 5 and the exhaust cabinet air cooling diffuser 7 is provided with the inflation cabinet air cooling diffuser control pneumatic switch valve 30 and the exhaust cabinet air cooling diffuser control pneumatic switch valve 31.

[0040] The pneumatic valve air supply branch 17 is connected to the inflation control pneumatic switch valve 20, the inflation control pneumatic regulating valve 21, the slope control exhaust pneumatic regulating valve 26, the exhaust control pneumatic switch valve 27, the inflation cabinet air cooling diffuser control pneumatic switch valve 30, and the exhaust cabinet air cooling diffuser control pneumatic switch valve 31 through a small branch.

[0041] The air pressure control device for detecting fuel tank seals in extreme climate environments disclosed in the above embodiment can be divided into two parts: an inflation device and an exhaust device. The inflation device mainly includes an inflation cabinet 1, an inflation cabinet air-cooled diffuser 5, an inflation cabinet electric heater 6, an air source access pipeline 9, an inflation branch 32, a pneumatic valve air supply branch 17 and related accessories. The exhaust device mainly includes an exhaust cabinet 2, an exhaust cabinet air-cooled diffuser 7, an exhaust cabinet electric heater 8, an exhaust pipeline 33, a slope-controlled exhaust branch 29, a switch-controlled exhaust branch 34, a manually-controlled exhaust branch 35 and related accessories. Through the coordinated control of the inflation device and the exhaust device, the internal pressure of the fuel tank changes according to the pressure test spectrum, thereby completing the fuel tank pressurization, pressure maintenance and pressure relief.

[0042] The charging device is used to process the compressed air of the air source to a dew point temperature of -40°C and a charging pressure of 0.2MPa to 0.8MPa.

[0043] The air source access pipeline 9 inlet passes through the inflation cabinet 1 and is connected to the compressed air source, which can be connected to the inflation device. The dryer 10 can process the compressed air to a dew point temperature of -40°C.

[0044] The compressed air pressure on the charging branch 32 can be adjusted to 0.2MPa~0.8MPa through the charging control pressure reducing valve 19, the opening of the charging control pneumatic regulating valve 21 can be controlled, and the punching rate of the fuel tank can be controlled according to the charging pressure-time curve.

[0045] The compressed air can be reduced to 0.6 MPa through the pneumatic valve air supply branch 17 to supply air to the pneumatic valves in the inflation device and the exhaust device, including the inflation control pneumatic switch valve 20, the inflation control pneumatic regulating valve 21, the slope control exhaust pneumatic regulating valve 26, the exhaust control pneumatic switch valve 27, the inflation cabinet air-cooled diffuser device control pneumatic switch valve 30, and the exhaust cabinet air-cooled diffuser device control pneumatic switch valve 31.

[0046] The electric heater 6 of the aeration cabinet can be activated in the low temperature environment of the climate laboratory 4 to maintain the interior of the aeration device cabinet 1 at 20°C to 30°C.

[0047] The air-cooled diffuser 5 of the inflatable cabinet can be activated in the high-temperature environment of the climate laboratory 4. The pneumatic valve air supply branch 17 branches off a compressed air path to supply the air-cooled diffuser 5 of the inflatable cabinet. The compressed air at room temperature can keep the interior of the inflatable device cabinet 1 at 20°C to 30°C.

[0048] The exhaust device is used to control the pressure relief rate after the fuel tank pressure maintenance is completed, or to provide emergency pressure relief after the pressure in the fuel tank exceeds the limit.

[0049] The slope of the exhaust branch 29 can be controlled by controlling the slope to control the opening of the exhaust pneumatic regulating valve 26, and the pressure relief rate in the fuel tank can be controlled according to the pressure relief-time curve.

[0050] The exhaust branch 34 can be controlled by opening the exhaust control pneumatic switch valve 27 to quickly release the pressure of the fuel tank.

[0051] The exhaust control manual valve 28 can be opened on the manual control exhaust branch 35 to quickly release the pressure of the fuel tank.

[0052] The exhaust cabinet electric heater 8 can be activated in the low temperature environment of the climate laboratory 4 to maintain the interior of the exhaust device cabinet 2 at 20°C to 30°C.

[0053] The exhaust cabinet air-cooling diffuser 7 can be activated in the high-temperature environment of the climate laboratory 4. The pneumatic valve air supply branch 17 branches off a path of compressed air to supply the exhaust cabinet air-cooling diffuser 7. The interior of the exhaust device cabinet 2 can be maintained at 20°C to 30°C by compressed air at room temperature.

[0054] The air pressure control device for detecting the seal of an aircraft fuel tank in an extreme climate environment disclosed in the above embodiment can be specifically applied when conducting a fuel tank seal detection test in an extreme climate environment in a climate laboratory 4.

[0055] The inflation cabinet 1 and the exhaust cabinet 2 are arranged near the wing 3 with the fuel tank, close to the fuel tank.

[0056] The inflatable cabinet 1 is connected to a compressed air source through an air source access pipe 9, and the compressed air is treated to a dew point temperature of -40°C by a dryer 10. The pressure of the compressed air after drying can be observed through an air source pressure indicating pressure gauge 11.

[0057] A pneumatic valve air supply branch 17 is provided in the inflation cabinet 1. When the pneumatic valve air supply branch control manual valve 12 is opened, the compressed air can pass through the filter 13 and the pneumatic valve air supply branch control pressure reducing valve 14 to reduce the compressed air to 0.6MPa, that is, the air pressure in the pneumatic valve air supply branch 17 is 0.6MPa, which is supplied to the pneumatic valves inside the inflation cabinet 1 and the exhaust cabinet 2. The pressure of the pneumatic valve air supply branch 17 can be monitored by the pneumatic valve air supply branch indicating pressure gauge 15 and the pneumatic valve air supply branch pressure transmitter 16.

[0058] An inflatable cabinet air-cooling diffuser 5 is provided in the inflatable cabinet 1, and the inflatable cabinet air-cooling diffuser 5 is connected to the pneumatic valve air supply branch 17. When the climate laboratory 4 is in a high temperature environment above 40°C, the inflatable cabinet air-cooling diffuser can be opened to control the pneumatic switch valve 30, and the interior of the inflatable cabinet 1 can be maintained at 20°C ~ 30°C by compressed air at normal temperature.

[0059] An electric heater 6 is provided in the aeration cabinet 1. When the climate laboratory 4 is in a low temperature environment below 0°C, the electric heater 6 can be turned on to keep the temperature inside the aeration cabinet 1 at 20°C to 30°C.

[0060] An exhaust cabinet air-cooling diffuser 7 is provided in the exhaust cabinet 2, and the exhaust cabinet air-cooling diffuser 7 is connected to the pneumatic valve air supply branch 17. When the climate laboratory 4 is in a high temperature environment above 40°C, the exhaust cabinet air-cooling diffuser 7 can be opened to control the pneumatic switch valve 31, and the interior of the exhaust cabinet 2 can be kept at 20°C to 30°C by compressed air at room temperature.

[0061] An exhaust cabinet electric heater 8 is provided in the exhaust cabinet 2. When the climate laboratory 4 is in a low temperature environment below 0°C, the exhaust cabinet electric heater 8 can be turned on to maintain the interior of the exhaust cabinet 2 at 20°C to 30°C.

[0062] When the fuel tank begins charging, the charging control manual valve 18 and the charging control pressure reducing valve 19 adjust the compressed air pressure to 0.2MPa-0.8MPa, then the charging control pneumatic on / off valve 20 opens. The slope control exhaust pneumatic regulating valve 26, exhaust control pneumatic on / off valve 27, and exhaust control manual valve 28 in the exhaust cabinet 2 are closed. The monitoring device uses the detection value of the fuel tank pressure transmitter 25 as the fuel tank pressure control feedback value to control the fuel tank charging rate by adjusting the opening of the charging control pneumatic regulating valve 21 in the charging cabinet 1. The pressure of the charging branch line 32 can be monitored via the charging branch line indicating pressure gauge 22 and the charging branch line pressure transmitter 23, and the fuel tank pressure can be monitored via the tank pressure indicating pressure gauge 24 and the tank pressure transmitter 25.

[0063] When the fuel tank needs to be depressurized, the inflation control pneumatic switch valve 20 and the inflation control pneumatic regulating valve 21 in the inflation cabinet 1 are closed, and the exhaust control pneumatic switch valve 27 and the exhaust control manual valve 28 in the exhaust cabinet 2 are closed. Using the monitor, the detection value of the fuel tank pressure transmitter 25 is used as the fuel tank pressure control feedback value, and the opening of the exhaust pneumatic regulating valve 26 is controlled by adjusting the slope to control the pressure relief rate of the fuel tank.

[0064] When emergency pressure relief is required for the fuel tank, close the inflation control pneumatic switch valve 20 and the inflation control pneumatic regulating valve 21 in the inflation cabinet 1, and perform emergency pressure relief on the slope control exhaust pneumatic regulating valve 26 and the exhaust control pneumatic switch valve 27 in the exhaust cabinet 2. Emergency pressure relief can also be performed by opening the exhaust control manual valve 28.

[0065] The air pressure control device for detecting the seal of an aircraft fuel tank in an extreme climate environment disclosed in the above embodiment has the following advantages:

[0066] Equipped with an air-cooling diffuser 5 for the inflation cabinet, an electric heater 6 for the inflation cabinet, an air-cooling diffuser 7 for the exhaust cabinet, and an electric heater 8 for the exhaust cabinet, the inflation cabinet 1 and the exhaust cabinet 2 can maintain a temperature of 20°C to 30°C, and can withstand the extreme environment of the climate laboratory 4. They can be arranged near the fuel tank in the climate laboratory 4, reducing the distance between the connecting pipe between the fuel tank pressure transmitter 25 and the fuel tank, improving the accuracy of the internal pressure detection of the fuel tank, and when the fuel tank pressure exceeds the limit, the exhaust-related pipes and control devices are close to the fuel tank, allowing for faster exhaust, which can effectively ensure the safety of the fuel tank sealing detection test;

[0067] The design has a triple over-pressure protection measure for the fuel tank. When the fuel tank pressure exceeds the limit, it can be relieved in three ways: one is to control the opening of the exhaust pneumatic regulating valve 26 by controlling the slope to use slope control to relieve pressure; the second is to quickly complete the pressure relief by opening the exhaust control pneumatic switch valve 27; the third is to manually complete the pressure relief by opening the exhaust control manual valve 28;

[0068] It supports two control modes: automatic and manual charging and pressure relief. One is to automatically control the charging and pressure relief rates of the fuel tank according to the charging-time curve and the pressure relief-time curve by using the charging control pneumatic regulating valve 21 and the slope control exhaust pneumatic regulating valve 26. The other is to manually control the charging control pneumatic switch valve 20, the charging control pneumatic regulating valve 21, and the slope control exhaust pneumatic regulating valve 26 to manually charge and relieve the pressure of the fuel tank.

[0069] The compressed air intake is dehumidified and a dryer 10 is installed on the air source access pipeline 9 to treat the compressed air to a dew point temperature of -40°C, which can reduce the risk of condensation and freezing of the compressed air when the oil tank is immersed in a low-temperature environment.

[0070] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or replacements to the relevant technical features, and the technical solutions after these changes or replacements will fall within the scope of protection of the present application.

Claims

1. An air pressure control device for detecting the sealing of an aircraft fuel tank in an extreme climate environment, characterized in that: It comprises an inflation cabinet (1), an exhaust cabinet (2), an inflation cabinet air cooling and dispersing device (5), an inflation cabinet electric heater (6), an exhaust cabinet air cooling and dispersing device (7), an exhaust cabinet electric heater (8), an air source access pipeline (9), an inflation branch (32), an exhaust pipeline (33), a slope control exhaust branch (29), a switch control exhaust branch (34), a manually controlled exhaust branch (35), and a pneumatic valve air supply branch (17); The inflation cabinet (1) and the exhaust cabinet (2) are arranged in a climate laboratory (4), close to a wing (3) with an oil tank in the climate laboratory (4); the inflation cabinet air cooling diffuser (5) and the inflation cabinet electric heater (6) are arranged in the inflation cabinet (1); the exhaust cabinet air cooling diffuser (7) and the exhaust cabinet electric heater (8) are arranged in the exhaust cabinet (2); An air source access pipeline (9) is provided in the inflation cabinet (1), and an inlet passes through the inflation cabinet (1) and is connected to a compressed air source; The inflation branch (32) is provided in the inflation cabinet (1), the inlet of which is connected to the outlet of the gas source access pipeline (9), and the outlet of which is connected to the oil tank. The inflation branch (32) is provided with an inflation control pressure reducing valve (19), an inflation control pneumatic switch valve (20), and an inflation control pneumatic regulating valve (21); An exhaust pipe (33) is provided in the exhaust cabinet (2), and its inlet is connected to the oil tank; The slope-controlled exhaust branch (29) is provided in the exhaust cabinet (2), the inlet of which is connected to the outlet of the exhaust pipe (33), and the outlet of which passes through the exhaust cabinet (2). The oil tank pressure transmitter (25) and the slope-controlled exhaust pneumatic regulating valve (26) are provided on the branch. The switch-controlled exhaust branch (34) is provided in the exhaust cabinet (2), the inlet of which is connected to the outlet of the exhaust pipe (33), and the outlet of which is connected to the slope-controlled exhaust branch (29), on which an exhaust-controlled pneumatic switch valve (27) is provided; A manually controlled exhaust branch (35) is provided in the exhaust cabinet (2), the inlet of which is connected to the outlet of the exhaust pipe (33), and the outlet of which is connected to the slope-controlled exhaust branch (29), on which an exhaust control manual valve (28) is provided; A pneumatic valve air supply branch (17) is provided in the inflation cabinet (1), the inlet of which is connected to the outlet of the air source access pipeline (9), the outlet of which passes through the inflation cabinet (1) and extends into the exhaust cabinet (2), and an air branch control pressure reducing valve (14) is provided on the pneumatic valve supply branch. The pneumatic valve supply branch (17) is connected to the inflation cabinet air cooling diffuser (5) and the exhaust cabinet air cooling diffuser (7) through a bypass, and an inflation cabinet air cooling diffuser control pneumatic switch valve (30) and an exhaust cabinet air cooling diffuser control pneumatic switch valve (31) are provided on the bypass connecting the inflation cabinet air cooling diffuser (5) and the exhaust cabinet air cooling diffuser (7).

2. The air pressure control device for detecting the sealing of an aircraft fuel tank in an extreme climate environment according to claim 1 is characterized in that: A dryer (10) and a gas source pressure indicating pressure gauge (11) are provided on the gas source access pipeline (9).

3. The air pressure control device for detecting the sealing of an aircraft fuel tank in an extreme climate environment according to claim 1 is characterized in that: The inflation branch (32) is also provided with an inflation control manual valve (18), an inflation control pneumatic regulating valve (21), an inflation branch indicating pressure gauge (22), and an inflation branch pressure transmitter (23).

4. The air pressure control device for detecting the sealing of an aircraft fuel tank in an extreme climate environment according to claim 1 is characterized in that: The slope control exhaust branch (29) is also provided with a tank pressure indicating pressure gauge (24).

5. The air pressure control device for detecting the sealing of an aircraft fuel tank in an extreme climate environment according to claim 1 is characterized in that: The pneumatic valve air supply branch (17) is connected to the inflation control pneumatic switch valve (20), the inflation control pneumatic regulating valve (21), the slope control exhaust pneumatic regulating valve (26), the exhaust control pneumatic switch valve (27), the inflation cabinet air cooling diffuser control pneumatic switch valve (30), and the exhaust cabinet air cooling diffuser control pneumatic switch valve (31) through a small branch.

Images