Device for air closing test of exhaust valve

Abstract

The application relates to a device for air closing valve test of an exhaust valve, which comprises an air compressor, an air tank, a manual butterfly valve, a first pressure gauge, a second pressure gauge, a straight pipe and a bent pipe. The air compressor outlet is connected with the air tank air inlet, the air tank top is provided with a first pressure gauge installation interface, the air outlet is connected with the manual butterfly valve inlet through the straight pipe, the manual butterfly valve outlet is connected with the exhaust valve installation interface through the bent pipe, and the exhaust valve installation interface side wall is provided with a second pressure gauge installation interface. The air tank is a cylindrical pressure container, the two ends are provided with hemispherical heads, and the lower part of the side wall is provided with a drain valve. Flange sealing structures are adopted at the connection positions, and a sealing gasket groove is arranged at the exhaust valve installation interface. A safety valve is arranged at the air tank top, an observation window is arranged at the side wall, and a support frame is arranged at the bottom. A pressure reducing valve is arranged between the air tank outlet and the manual butterfly valve. A quick clamping mechanism is arranged at the exhaust valve installation interface. An air filter is arranged at the air compressor air inlet. The device can effectively simulate the pressure difference condition required by the air closing valve test of the exhaust valve.

Description

Technical Field

[0001] This application relates to the technical field of exhaust valve performance testing equipment, and more specifically, to a device for air closure testing of exhaust valves and its improved structure. Background Technology

[0002] With the development of exhaust valve testing technology, various exhaust valve testing devices have been widely used in the industrial field. However, in practical applications, existing technologies still have some problems, especially in the design of devices for exhaust valve air closure testing, where some technical solutions cannot fully meet the requirements for accurate testing and ease of operation.

[0003] A search revealed a testing device for an exhaust valve, publication number CN108286625B, published on May 28, 2024. This device, through the sequential connection of a gas storage area, a gas collection area, and a testing area, enables the detection of exhaust volume under different pressure differentials in a composite exhaust valve. Its structure is simple, operation is convenient, and it is suitable for performance testing of composite exhaust valves. However, this device primarily focuses on detecting exhaust volume and does not specifically simulate and measure the air-closed valve pressure differential (i.e., the exhaust pressure differential at the moment the float is blown up and the valve closes). Furthermore, its pressure control method relies on manually adjusting the flow valve, making automated testing difficult, and it has limitations when high-precision pressure differential measurement is required, failing to meet the test requirement of GB / T 36523 that the air-closed valve pressure differential of the exhaust valve should not be less than 0.09 MPa.

[0004] A search revealed a device (CN114252210B) for low-pressure sealing testing of composite high-speed intake and exhaust valves, published on July 11, 2025. This device, by employing a U-shaped flow channel and a unidirectional flow channel, can achieve a stable 0.02MPa low-pressure sealing test environment at a relatively low cost. Its structure is simple and easy to operate, making it suitable for low-pressure sealing performance testing. However, the design focus of this device is on verifying low-pressure sealing performance and does not include testing the air-closed valve pressure differential. Furthermore, because its test pressure range is limited to low-pressure sealing conditions, it cannot cover the higher pressure range required for air-closed valve testing (such as 0.09MPa and above), and therefore cannot be directly used for testing air-closed valve pressure differentials.

[0005] The aforementioned problems indicate that current exhaust valve testing devices on the market have significant shortcomings in testing air-closed valve pressure differentials, particularly in accurately simulating air-closed valve pressure differentials, achieving automated testing, and covering a wider pressure range. Therefore, this invention provides a device for testing the air-closed valve of an exhaust valve, aiming to solve the above problems and provide a more accurate, efficient, and adaptable solution. Summary of the Invention

[0006] The purpose of this application is to provide an apparatus for testing the air closure of an exhaust valve, which has the advantages of improving pressure control accuracy, enhancing safety protection capabilities, and optimizing sealing performance.

[0007] This application provides an apparatus for testing the air closure of an exhaust valve, the technical solution of which is as follows: The system includes an air compressor, an air tank, a manual butterfly valve, a first pressure gauge, a second pressure gauge, straight pipes, and bends. The outlet of the air compressor is connected to the inlet of the air tank. The top of the air tank has a mounting interface for the first pressure gauge, which is fixedly installed on the first pressure gauge mounting interface. The outlet of the air tank is connected to the inlet of the manual butterfly valve via a straight pipe. The outlet of the manual butterfly valve is connected to the mounting interface of the exhaust valve via a bend. The side wall of the exhaust valve mounting interface has a mounting interface for the second pressure gauge, which is fixedly installed on the second pressure gauge mounting interface. The air tank is a cylindrical pressure vessel with hemispherical end caps at both ends. A drain valve is located on the lower part of the side wall of the air tank. The outlet of the air compressor is connected to the inlet of the air tank via a quick connector. Flange sealing structures are used between the outlet of the air tank and the straight pipe, between the straight pipe and the inlet of the manual butterfly valve, and between the outlet of the manual butterfly valve and the bend. A sealing gasket groove is provided at the exhaust valve mounting interface, and a rubber sealing gasket is placed in the groove. The inner diameter of the exhaust valve mounting interface matches the interface size of the exhaust valve.

[0008] Furthermore, this application also proposes that the top of the gas storage tank is equipped with a safety valve; the set pressure of the safety valve is 0.5 MPa; the outlet of the safety valve is connected to an exhaust pipe; the safety valve adopts a spring direct load structure; the valve disc of the safety valve is a full-opening structure; the side wall of the gas storage tank is equipped with an observation window; the observation window is made of tempered glass; the edge of the observation window is sealed with a rubber sealing strip; a protective cover is provided on the outside of the observation window; and a support frame is provided at the bottom of the gas storage tank.

[0009] Furthermore, this application also proposes that the support frame is welded from four channel steels; the lower part of the support frame is provided with adjusting bolts; the bottom of the adjusting bolts is provided with anti-slip pads; a pressure reducing valve is provided between the outlet of the gas storage tank and the manual butterfly valve; the inlet pressure range of the pressure reducing valve is 0 to 0.6 MPa; the outlet pressure range of the pressure reducing valve is 0 to 0.3 MPa.

[0010] Furthermore, this application also proposes that a quick clamping mechanism be provided at the exhaust valve mounting interface; the quick clamping mechanism includes a fixed frame, a clamping rod and a handle; the fixed frame is welded to the end of the bend; the clamping rod is hinged to the fixed frame by a pin; the handle is fixed to the end of the clamping rod; and a pressure block is provided in the middle of the clamping rod.

[0011] Furthermore, this application also proposes that the air compressor's air inlet is equipped with an air filter; the air filter element is a paper filter element; a drain valve is provided at the bottom of the air filter; and a protective net is provided at the air inlet of the air filter.

[0012] The beneficial effects of this invention are reflected in the following aspects: This utility model discloses a device for testing the air closure of an exhaust valve. It establishes a stable air source through a combination of an air compressor and an air tank, forms a gas passage using straight and curved pipes, controls flow with a manual butterfly valve, and monitors the pressure in the air tank and at the exhaust valve mounting interface using a first and a second pressure gauge, respectively. The cylindrical structure of the air tank, combined with a hemispherical end cap, enhances its pressure-bearing capacity, and the drain valve facilitates the removal of condensate. Quick-connect couplings and flange sealing structures ensure airtightness at all connections. The sealing gasket groove and matching inner diameter design of the exhaust valve mounting interface guarantee a tight connection with the exhaust valve. A safety valve provides overpressure protection, an observation window facilitates internal status monitoring, and a support frame and adjusting bolts provide stable support and horizontal adjustment. The introduction of a pressure reducing valve enables precise control of the outlet pressure. A quick-clamping mechanism, through the cooperation of a fixing frame, clamping rod, and handle, enables rapid installation and fixation of the exhaust valve. An air filter ensures the cleanliness of the incoming air. The device has a reasonable structural design and clear component connection relationships. It can effectively simulate the differential pressure conditions required for the air closure test of the exhaust valve and has the characteristics of convenient operation and safety and reliability. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of a device for testing the air closure of an exhaust valve according to the present invention. Figure 2 This is a schematic diagram of the gas storage tank structure according to an embodiment of this application; Figure 3 This is a partially enlarged schematic diagram of the quick clamping mechanism of a device for testing the air closure valve of an exhaust valve according to the present invention.

[0014] Explanation of reference numerals in the attached drawings: 1. Air compressor; 2. Air tank; 3. Manual butterfly valve; 4. First pressure gauge; 5. Second pressure gauge; 6. Straight pipe; 7. Bend; 8. Handle; 11. Exhaust valve mounting interface; 12. Safety valve; 13. Drain valve; 14. Observation window; 17. Fixing bracket; 18. Quick clamping mechanism; 19. Support frame; 20. Pressure reducing valve; 21. Air filter; 22. Clamping rod; 23. Exhaust valve. Detailed Implementation

[0015] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. The components of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0016] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0017] In existing technologies, exhaust valve testing devices mostly focus on flow detection or low-pressure sealing performance verification, lacking the ability to accurately simulate the differential pressure of air-closed valves. Traditional devices rely on manually adjusting the flow valve to control pressure, making it difficult to achieve a stable air source output, resulting in insufficient test accuracy. Some solutions are limited by structural design and cannot adapt to the installation requirements of exhaust valves 23 of different specifications, making them prone to sealing failure during testing.

[0018] To address the aforementioned issues, researchers found that existing pressure control systems struggled to capture instantaneous pressure differential changes during valve closure, and manual adjustment was prone to human error. By analyzing the impact of gas source stability on test results, a closed-loop pressure monitoring system combining a gas storage tank and dual pressure gauges was proposed. To address the sealing challenges of the tested valve, standardized interfaces and flange sealing structures were designed to ensure test compatibility and airtightness.

[0019] Therefore, this application proposes an apparatus including an air compressor 1, an air tank 2, a manual butterfly valve 3, a first pressure gauge 4, a second pressure gauge 5, a straight pipe 6, and a bend 7. The outlet of the air compressor 1 is connected to the inlet of the air tank 2. The first pressure gauge 4 is installed on the top of the air tank 2. The outlet of the air compressor 1 is connected to the inlet of the manual butterfly valve 3 via the straight pipe 6. The outlet of the manual butterfly valve 3 is connected to the mounting interface 11 of the exhaust valve 23 via the bend 7. The second pressure gauge 5 is installed on the side wall of this interface. The air tank 2 is a cylindrical pressure vessel with a hemispherical head, and a drain valve 13 is provided on the lower part of the side wall. A quick-connect coupling is used between the air compressor 1 and the air tank 2, and flange sealing structures are used at all pipe connections. The mounting interface 11 of the exhaust valve 23 is provided with a sealing gasket groove and a matching interface size.

[0020] Among them, cylindrical pressure vessels refer to axially symmetrical closed containers, which can be made by rolling and welding Q345R steel plates. The hemispherical heads at both ends are formed by spinning. This structure can evenly distribute the internal pressure and improve the pressure resistance of the container.

[0021] Among them, the flange sealing structure refers to the pipeline connection method that is fastened by flange and bolts. Specifically, the plate flat welding flange in HG / T 20592 standard can be used, and asbestos rubber gaskets can be used to achieve high-pressure gas sealing and prevent pipeline leakage from causing pressure fluctuations.

[0022] The sealing gasket groove refers to the annular groove opened on the end face of the mounting interface 11 of the exhaust valve 23. Specifically, it can be formed into a rectangular groove with a width of 5 mm by CNC machine tool. A nitrile rubber gasket is placed in the groove, and the gasket is deformed to fill the gap by clamping force to ensure the airtightness of the valve under test.

[0023] Quick couplings refer to fluid connectors that allow for rapid assembly and disassembly. Specifically, they can be threaded locking couplings as specified in ISO 16028, with an internal one-way valve to prevent gas backflow, facilitating quick separation of the air compressor 1 from the air tank 2.

[0024] Specifically, air compressor 1 inputs compressed air into air tank 2, and the pressure inside the tank is monitored in real time by the first pressure gauge 4. When the pressure reaches the set value, the manual butterfly valve 3 is opened, allowing the gas to flow through the straight pipe 6 and the bend pipe 7 to the exhaust valve 23 under test. The second pressure gauge 5 continuously monitors the pressure before the valve. When the pressure difference triggers the valve closing action, the comparison of the data from the two pressure gauges can accurately capture the valve closing pressure difference threshold. The cylindrical structure of air tank 2, combined with the hemispherical head, enhances its pressure resistance, and the drain valve 13 periodically drains condensate to maintain stable pressure. The flange connection ensures the pipeline is airtight, preventing air leakage from interfering with the test results. The sealing gasket groove and the matching interface size ensure an effective seal after the valve under test is installed, eliminating the influence of installation gaps on pressure measurement.

[0025] Compared to existing technologies, traditional devices use a single pressure gauge to monitor the pressure of gas storage tank 2, which cannot directly obtain the pressure data before the valve, leading to errors in the calculation of the differential pressure at the valve closure. This solution uses two pressure gauges to simultaneously monitor the outlet pressure of gas storage tank 2 and the pressure before the valve, directly obtaining the differential pressure data and avoiding indirect calculation errors. In existing technologies, gas storage tank 2 often uses a rectangular structure, which can easily lead to seal failure due to localized stress concentration. This solution uses a cylindrical structure with a hemispherical head to optimize stress distribution and improve the safety of the testing process. Traditional pipelines use threaded connections that are prone to loosening and leakage. This solution's flange sealing structure uses bolts to apply pressure evenly, ensuring reliable sealing under high pressure.

[0026] Through the above technical solutions, this application achieves direct and accurate measurement of the differential pressure at the closed valve of the exhaust valve 23, meeting the standard requirement of a 0.09MPa threshold detection. Simultaneous monitoring with dual pressure gauges eliminates indirect calculation errors, the flange sealing structure maintains system airtightness, and quick-connect couplings and standardized interfaces improve the efficiency of device assembly and disassembly. The structural design of the gas storage tank 2 effectively stabilizes the gas source output, and the drain valve 13 promptly removes condensate interference, ensuring accurate and reliable test data.

[0027] This application further proposes that a safety valve 12 be installed on the top of the gas storage tank 2, the safety valve 12 be set at a pressure of 0.5 MPa, the outlet of the safety valve 12 be connected to an exhaust pipe, the safety valve 12 be adopted as a direct spring load structure, the valve disc of the safety valve 12 be a full-opening structure, an observation window 14 be installed on the side wall of the gas storage tank 2, the observation window 14 be made of tempered glass, the edge of the observation window 14 be sealed with a rubber sealing strip, a protective cover be installed on the outside of the observation window 14, and a support frame 19 be installed at the bottom of the gas storage tank 2.

[0028] Among them, the spring direct load structure refers to a valve type in which the spring force acts directly on the valve disc. Specifically, it can be implemented using a structure where a pre-tensioned spring is connected to the valve stem. This structure can quickly respond to pressure changes and open automatically. The full-opening valve disc refers to a structure where the medium flow area reaches its maximum after the valve disc opens. Specifically, it can be implemented using a structure where the valve seat and valve disc mating surfaces are flat seals. This structure can achieve large-flow release when opened. The tempered glass observation window 14 refers to glass material that has undergone heat treatment to enhance its strength. Specifically, it can be made of 10mm thick tempered glass, which is not easily broken under pressure fluctuations. The rubber sealing strip refers to a sealing element made of elastic rubber material. Specifically, it can be implemented by embedding a nitrile rubber strip into the window frame groove. This method can prevent gas leakage from the edges of the observation window 14. The protective cover refers to the metal frame structure covering the outside of the observation window 14. Specifically, it can be implemented by welding a stainless steel perforated plate to a bracket. This structure can prevent external impacts from damaging the observation window 14. The support frame 19 refers to the rigid frame that bears the weight of the gas storage tank 2. Specifically, it can be achieved by welding four channel steels into a rectangular base. This structure can distribute the weight of the gas storage tank 2 and keep the device stable.

[0029] Specifically, when the internal pressure of the gas storage tank 2 exceeds 0.5 MPa, the valve disc of the spring-loaded safety valve 12 rises rapidly under the pressure of the medium, overcoming the spring preload. The full-opening structure allows the venting channel to be fully opened, and the high-pressure gas is discharged directionally through the exhaust pipe, preventing damage to the container caused by continuous pressure increases. The tempered glass of the observation window 14 can withstand pressure fluctuations inside the tank. Operators can visually monitor the gas status inside the tank in real time. The rubber sealing strip and the protective cover provide double protection, ensuring both sealing and preventing accidental glass breakage. The channel steel welded structure of the support frame 19 increases the contact area to improve overall stability. The adjusting bolts, combined with anti-slip pads, can adapt to different ground conditions, ensuring that the device does not tilt or shift during high-pressure testing.

[0030] Compared to existing technologies, traditional exhaust valve 23 testing devices often lack safety relief devices, relying solely on manual valve pressure adjustment, which poses a risk of overpressure explosion. For example, the testing device disclosed in CN108286625B, while having a gas storage area, lacks an automatic safety valve 12, resulting in insufficient pressure control accuracy. This solution, however, achieves rapid automatic relief when pressure exceeds limits through a combination of a spring-loaded direct-load safety valve 12 and a full-opening valve disc. Furthermore, existing technologies lack real-time monitoring methods for the internal state of the gas storage tank 2. This solution, through a combination of a tempered glass observation window 14 and a protective cover, achieves visual monitoring while ensuring safety. Regarding device stability, traditional support structures are mostly fixed brackets, making them unsuitable for uneven ground. This solution, through the combination of adjustable bolts and anti-slip pads, significantly improves the stability of the equipment under different operating conditions.

[0031] Through the above technical solutions, this application solves the risk of overpressure that may occur in the gas storage tank 2 during high-pressure testing and realizes automatic safety protection when the pressure exceeds the limit; through the design of the visualization observation window 14, the operator can monitor the changes in the state of the medium inside the tank in real time; through the adjustable support frame 19 structure, the stability of the device in different test environments is enhanced, while simplifying the equipment installation and commissioning process.

[0032] This application further proposes that the support frame 19 is welded from four channel steels, and the lower part of the support frame 19 is provided with adjusting bolts. The bottom of the adjusting bolts is provided with anti-slip pads. A pressure reducing valve 20 is provided between the outlet of the gas storage tank 2 and the manual butterfly valve 3. The inlet pressure range of the pressure reducing valve 20 is zero to 0.6 MPa, and the outlet pressure range is zero to 0.3 MPa.

[0033] The support frame 19 is constructed from four welded channel steels. This means it uses four standard channel steels welded together to form a frame structure, specifically Q235B channel steel. The four channel steels are symmetrically distributed to form a stable support surface, and the welded connection ensures overall rigidity. The adjusting bolts are threaded adjustment rods, specifically M16 stainless steel bolts. Rotation adjusts the height of each support point of the support frame 19 to compensate for uneven ground. The anti-slip pads are friction-enhancing pads, specifically rubber pads with anti-slip textures, increasing the coefficient of friction to prevent slippage of the support frame 19. The pressure reducing valve 20 is a valve that reduces and stabilizes fluid pressure. A pilot-operated piston type pressure reducing valve 20 controls the outlet pressure range by adjusting the spring preload, stabilizing the pressure output from the gas storage tank 2 within a set range.

[0034] Specifically, the support frame formed by welding four channel steels is symmetrically arranged to distribute the load evenly. The web and flange structure of the channel steels provide sufficient bending strength to prevent vibration displacement of the gas storage tank 2 due to pressure fluctuations. Adjusting bolts are installed at the four corners of the bottom of the support frame 19. The extension length of each bolt is adjusted by independent rotation to keep the support frame 19 horizontal. The anti-slip pads increase friction through surface texture after contacting the ground, preventing the device from slipping due to airflow impact during the test. The pressure reducing valve 20 is installed on the outlet pipe of the gas storage tank 2. When the pressure inside the gas storage tank 2 fluctuates, the pressure reducing valve 20 automatically adjusts the valve core opening through an internal feedback mechanism to stabilize the outlet pressure within a preset range, ensuring that the pressure at the inlet of the manual butterfly valve 3 remains constant and eliminating the impact of pressure fluctuations on the accuracy of the differential pressure test.

[0035] Compared with existing technologies, traditional testing devices mostly use fixed supports and lack pressure stabilization devices, which makes them prone to displacement due to vibration during testing, and pressure fluctuations directly affect the accuracy of test results. This solution solves the stability problem of the device and achieves precise control of the output pressure by combining an adjustable support frame 19 with a pressure reducing valve 20.

[0036] Through the above technical solution, this application effectively prevents the gas storage tank 2 from tilting or displacing due to pressure changes, ensuring that the testing device maintains a stable posture during the test. At the same time, through the secondary pressure regulation function of the pressure reducing valve 20, the output pressure is stabilized within the range required for the closed valve differential pressure test, meeting the pressure threshold requirements specified in the standard, and improving the accuracy and repeatability of the test data.

[0037] This application further proposes that a quick clamping mechanism 18 is provided at the installation interface 11 of the exhaust valve 23. The quick clamping mechanism 18 includes a fixed frame 17, a clamping rod 22 and a handle 8. The fixed frame 17 is welded to the end of the bend 7, the clamping rod 22 is hinged to the fixed frame 17 by a pin, the handle 8 is fixed to the end of the clamping rod 22, and a pressure block is provided in the middle of the clamping rod 22.

[0038] The quick-clamping mechanism 18 refers to a device that achieves rapid locking and releasing through mechanical linkage. Specifically, it can be implemented using a structure where a hinged pressure rod and a fixed frame 17 cooperate. When the pressure rod 22 rotates around the pin, it drives the pressure block to apply vertical pressure to the interface. The fixed frame 17 refers to a rigid frame used to support the pressure rod 22. Specifically, it can be made of steel plate welded together and then welded to the end of the bend 7 to form a stable force-bearing fulcrum. The pressure block refers to the force-applying component located in the middle of the pressure rod 22. Specifically, it can be a metal block with anti-slip texture on its surface, which contacts the surface of the exhaust valve 23 mounting interface 11 and evenly distributes pressure during clamping.

[0039] Specifically, when the handle 8 rotates the clamping rod 22 around the pin, the pressure block moves downward with the lever movement of the clamping rod 22, applying vertical pressure to the sealing gasket groove of the mounting interface 11 of the exhaust valve 23, forcing the rubber sealing gasket to deform and fill the gap. With the clamping rod 22 fully closed, the pressure block forms surface contact with the interface surface, preventing localized stress concentration that could lead to seal failure. After the test is completed, reversing the handle 8 quickly releases the pressure, allowing for easy disassembly of the exhaust valve 23.

[0040] Compared with existing technologies, traditional exhaust valve 23 test devices mostly use bolt fastening to fix the valve under test, which requires tightening multiple bolts one by one and it is difficult to apply force evenly, resulting in unstable sealing performance and time-consuming operation. This solution replaces multi-bolt fastening with single-point operation of a hinged pressure rod, and uses the lever principle to convert the operating force of the handle 8 into uniform pressure of the pressure block on the interface, which simplifies the clamping steps and improves sealing reliability.

[0041] Through the above technical solution, this application solves the problems of insufficient sealing of the installation interface 11 of the exhaust valve 23 and cumbersome operation, realizes quick clamping and reliable sealing of the interface during the test, avoids pressure leakage caused by uneven manual force application, and reduces the installation time of a single valve to less than one-fifth of the traditional method.

[0042] This application further proposes that the air compressor 1 is provided with an air filter 21 at the air inlet, the filter element of the air filter 21 is a paper filter element, the bottom of the air filter 21 is provided with a drain valve 13, and the air inlet of the air filter 21 is provided with a protective net.

[0043] The air filter 21 is a filtration device installed in the air intake channel of the air compressor 1. It can be implemented using a multi-layer filtration structure to intercept solid particles in the air. The paper filter element is a filter medium made of cellulose material, which can be implemented using a pleated structure design to balance filtration efficiency and airflow by increasing the filtration area. The drain valve 13 is a liquid discharge device installed at the bottom of the filter, which can be implemented using a manual stopcock valve structure to periodically drain accumulated liquid water. The protective net is a mesh structure covering the outer layer of the air intake, which can be implemented using stainless steel woven mesh to prevent large foreign objects such as leaves and insects from entering.

[0044] Specifically, air filter 21 uses a paper filter element to finely filter the intake air, effectively trapping fine particles such as dust. A protective mesh acts as a primary barrier, preventing larger foreign objects from clogging the filter element prematurely. Drain valve 13 periodically opens to discharge condensate, preventing liquid water from entering the compression system. The pleated structure of the paper filter element forms a high-density filter layer within a limited space, maintaining sufficient airflow while ensuring filtration accuracy. These components form a multi-level protection system, achieving comprehensive air purification from physical interception to moisture removal, preventing impurities from damaging the internal components of air compressor 1, and ensuring the cleanliness of the compressed air used in the test.

[0045] Compared to existing technologies, traditional exhaust valve 23 testing devices typically lack an intake filtration system or use only a single-layer metal filter for simple protection. This solution achieves multi-stage purification through a combined filtration structure, with the paper filter element significantly improving the interception capability for micron-sized particles compared to a metal filter. The addition of the drain valve 13 solves the problem of condensate buildup leading to corrosion of pneumatic components in traditional devices. The synergistic effect of the protective mesh and filter extends the filter element's lifespan and reduces maintenance frequency compared to a single filtration structure.

[0046] Through the above technical solutions, this application effectively prevents external impurities from entering the compression system of air compressor 1, avoiding wear of cylinders and valve plates by particulate matter and reducing equipment failure rate. By eliminating liquid water and solid contaminants, the purity of the compressed air used for testing is ensured, so that the differential pressure test data with closed valves is not affected by gas quality, significantly improving the accuracy of test results. The multi-stage protection structure achieves continuous filtration while maintaining normal air intake, ensuring the stability of the test device operation.

[0047] This application further proposes that the air compressor 1 is provided with an air filter 21 at the air inlet, the filter element of the air filter 21 is a paper filter element, the bottom of the air filter 21 is provided with a drain valve 13, and the air inlet of the air filter 21 is provided with a protective net.

[0048] Among them, the air filter 21 refers to a device used to intercept solid particles in the air, which can be implemented by adopting a multi-layer filtration structure. Its function is to prevent impurities from entering the compressed air system.

[0049] Among them, paper filter cartridges refer to replaceable filter elements made of cellulose materials. Specifically, they can be implemented using a pleated design. Their function is to balance filtration accuracy and cost, while also facilitating replacement and maintenance.

[0050] Among them, drain valve 13 is a valve used to drain liquid residue. Specifically, it can be implemented by a manual plug structure. Its function is to periodically remove accumulated water or oil stains to prevent filter element blockage.

[0051] The protective netting refers to the mesh structure covering the outside of the air inlet, which can be made of woven stainless steel wire. Its function is to block large particles of foreign matter from entering the filter and extend the service life of the filter element.

[0052] Specifically, during the air intake process of air compressor 1, air first passes through a protective mesh to intercept large particles such as leaves and insects, and then enters air filter 21. The paper filter element, with its pleated structure, increases the filtration area, effectively adsorbing dust and fine particles to ensure the cleanliness of the compressed air. During filtration, moisture and oil in the air settle to the bottom of the filter under gravity and are discharged periodically by opening the drain valve 13, preventing liquid residue from causing a decline in filter element performance. The easy replacement of the paper filter element simplifies maintenance, and the presence of the protective mesh further reduces the contamination load on the filter element, thereby reducing the frequency of maintenance.

[0053] Compared to existing technologies, current solutions typically only have a single-layer filter structure or no protective measures at the air compressor inlet, making it easy for impurities to enter the system and affect testing accuracy, and requiring frequent filter replacements. This solution, through the coordinated design of a protective mesh, multi-stage filtration, and drain valve 13, improves filtration efficiency, significantly extends filter life, and simplifies maintenance procedures.

[0054] Through the above technical solutions, this application effectively prevents impurities from entering the compressed air system and avoids test data deviation; the drain valve 13 removes liquid residue in a timely manner, maintaining the stable performance of the filter; the combined design of the protective net and the paper filter element reduces the rate of filter element contamination and the number of maintenance operations, thereby ensuring the long-term reliability of the test device.

[0055] This application further proposes to install an air filter 21 at the air inlet of the air compressor 1. The filter element of the air filter 21 is a paper filter element. A drain valve 13 is provided at the bottom of the air filter 21. A protective net is provided at the air inlet of the air filter 21.

[0056] The air filter 21 refers to the filter device installed in the air intake channel of the air compressor 1. It can be implemented using a multi-layer composite filter structure to intercept solid particles in the air. The paper filter element is a replaceable filter element made of cellulose material, which can be implemented using a pleated structure to reduce airflow resistance while ensuring filtration accuracy. The drain valve 13 is a liquid discharge device installed at the bottom of the filter, which can be implemented using a manual stopcock valve to periodically drain accumulated liquid water. The protective mesh is a metal mesh structure covering the air inlet of the filter, which can be implemented using a perforated stainless steel plate to prevent large foreign objects from entering.

[0057] Specifically, the protective net, acting as a primary filtration barrier, effectively intercepts large particles such as leaves and fibers. The paper filter element inside the air filter 21, with its micron-sized pore structure, further filters fine dust particles. When moisture entrained in the compressed air condenses inside the filter, the accumulated water can be periodically drained through the bottom drain valve 13. This multi-stage filtration mechanism prevents impurities from entering the air compressor 1 cylinder and causing piston wear, and also prevents liquid water from mixing into the compressed air and causing pressure fluctuations in the air tank 2.

[0058] Compared with existing technologies, the testing device in publication number CN108286625B lacks an air intake filtration system, which can easily lead to the air compressor 1 drawing in impurities when operating in dusty environments. While the low-pressure sealing test device in publication number CN114252210B involves pressure control, it does not mention air intake filtration design. This solution constructs a complete air intake purification system through a combination of a protective mesh and a paper filter element, combined with the liquid separation function of the drain valve 13.

[0059] Through the above technical solution, this application solves the problems of test data deviation and equipment wear caused by impurities sucked into the air compressor 1. Multi-stage filtration and liquid water separation ensure the quality of compressed air, improve the pressure stability of the air tank 2, and extend the maintenance cycle of the air compressor 1.

[0060] This application further proposes that the air compressor 1 is provided with an air filter 21 at the air inlet, the filter element of the air filter 21 is a paper filter element, the bottom of the air filter 21 is provided with a drain valve 13, and the air inlet of the air filter 21 is provided with a protective net.

[0061] The air filter 21 is a filtration device installed at the front end of the air intake channel of the air compressor 1. It can be implemented using a multi-layer metal frame and filter element combination structure to intercept particulate impurities in the outside air. The paper filter element is a filter medium formed by stacking multiple layers of fiber paper, which can be implemented using a pleated structure to intercept small particles through the fiber gaps. The drain valve 13 is a liquid discharge device installed at the bottom of the air filter 21, which can be implemented using a manual stopcock valve structure to periodically drain moisture condensed inside the filter. The protective net is a mesh structure covering the air intake of the air filter 21, which can be implemented using a stainless steel wire mesh to prevent large particles such as leaves or insects from entering.

[0062] Specifically, when air compressor 1 is running, outside air first undergoes primary filtration through a protective mesh, blocking large particles outside the air inlet. The air then enters the paper filter element, where the fiber layer further intercepts smaller particles. The filtered clean air then enters air compressor 1 for compression, preventing impurities from contaminating the compressed air and affecting test accuracy. During air compression, some moisture condenses at the bottom of the filter due to temperature changes; this water can be drained from the system periodically by opening the drain valve 13. The pleated structure of the paper filter element increases the effective filtration area, extending the replacement cycle while ensuring filtration efficiency.

[0063] Compared to existing technologies, the traditional exhaust valve 23 test device lacks a pre-filtration system, allowing impurities and moisture in the air to directly enter the test pipeline, affecting the accuracy of pressure measurements. This solution addresses this issue by adding a multi-stage protective air filter to intercept particulate matter and separate moisture before compressed air enters the system, thus resolving the problem of environmental interference with test data in existing technologies.

[0064] Through the above technical solutions, this application effectively prevents external foreign objects from entering the test system, ensures the cleanliness of compressed air, improves the accuracy of valve-closed differential pressure testing, and extends the service life of the equipment and reduces the frequency of system maintenance through the design of maintainable filter components.

Claims

1. An apparatus for testing the air closure of an exhaust valve, characterized in that, The system includes an air compressor (1), an air tank (2), a manual butterfly valve (3), a first pressure gauge (4), a second pressure gauge (5), a straight pipe (6), and a bend pipe (7); the outlet of the air compressor (1) is connected to the inlet of the air tank (2); the top of the air tank (2) is provided with a first pressure gauge mounting interface, and the first pressure gauge (4) is fixedly installed on the first pressure gauge mounting interface; the outlet of the air tank (2) is connected to the inlet of the manual butterfly valve (3) through the straight pipe (6); the outlet of the manual butterfly valve (3) is connected to the exhaust valve (23) mounting interface (11) through the bend pipe (7); the side wall of the exhaust valve (23) mounting interface (11) is provided with a second pressure gauge mounting interface, and the second pressure gauge... Table (5) is fixedly installed on the second pressure gauge mounting interface; the air tank (2) is a cylindrical pressure vessel with hemispherical end caps at both ends; a drain valve (13) is provided on the lower side wall of the air tank (2); the outlet of the air compressor (1) is connected to the air inlet of the air tank (2) through a quick connector; the air outlet of the air tank (2) and the straight pipe (6), the straight pipe (6) and the inlet of the manual butterfly valve (3), and the outlet of the manual butterfly valve (3) and the bend pipe (7) are all sealed with flanges; a sealing gasket groove is provided at the mounting interface (11) of the exhaust valve (23), and a rubber sealing gasket is placed in the groove; the inner diameter of the mounting interface (11) of the exhaust valve (23) matches the interface size of the exhaust valve (23).

2. The apparatus for testing the air closure of an exhaust valve according to claim 1, characterized in that, The gas storage tank (2) is equipped with a safety valve (12) at the top; the set pressure of the safety valve (12) is 0.5 MPa; the outlet of the safety valve (12) is connected to an exhaust pipe; the safety valve (12) adopts a spring direct load structure; the valve disc of the safety valve (12) is a full-opening structure; the side wall of the gas storage tank (2) is equipped with an observation window (14); the observation window (14) is made of tempered glass; the edge of the observation window (14) is sealed with a rubber sealing strip; a protective cover is provided on the outside of the observation window (14); and a support frame (19) is provided at the bottom of the gas storage tank (2).

3. The apparatus for testing the air closure of an exhaust valve according to claim 2, characterized in that, The support frame (19) is welded from four channel steels; the lower part of the support frame (19) is provided with adjusting bolts; the bottom of the adjusting bolts is provided with anti-slip pads; a pressure reducing valve (20) is provided between the outlet of the gas storage tank (2) and the manual butterfly valve (3); the inlet pressure range of the pressure reducing valve (20) is 0 to 0.6 MPa; the outlet pressure range of the pressure reducing valve (20) is 0 to 0.3 MPa.

4. The apparatus for testing the air closure of an exhaust valve according to claim 1, characterized in that, The exhaust valve (23) is provided with a quick clamping mechanism (18) at the mounting interface (11); the quick clamping mechanism (18) includes a fixed frame (17), a clamping rod (22) and a handle (8); the fixed frame is welded to the end of the bent pipe (7); the clamping rod is hinged to the fixed frame by a pin; the handle is fixed to the end of the clamping rod; a pressure block is provided in the middle of the clamping rod.

5. The apparatus for testing the air closure of an exhaust valve according to claim 1, characterized in that, The air compressor (1) is equipped with an air filter (21) at its air inlet; the filter element of the air filter (21) is a paper filter element; a drain valve is provided at the bottom of the air filter (21); and a protective net is provided at the air inlet of the air filter (21).

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