Air tightness test device
By designing an airtightness testing device, the problem of testing the airtightness of the cut-off valve under different temperature environments was solved, achieving efficient and accurate airtightness detection and analysis, and ensuring the normal function of the braking system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-02
- Publication Date
- 2026-04-03
AI Technical Summary
Existing technologies make it difficult to effectively test the airtightness of the cut-off valve under simulated temperature environments, which may cause it to fail under high and low temperature conditions, affecting the normal function of the braking system.
An airtightness testing device was designed, including a temperature change test chamber, a pressure measuring device, an air cylinder, a sample connecting pipe, and an air pressure source. By simulating the airtightness changes of airtight products under high and low temperature environments, automated testing is achieved using a high-precision pressure sensor and control device.
It can accurately detect changes in the airtightness of shut-off valves under high and low temperature environments, provide pressure change data, and be used to analyze and improve the internal structure of airtight products, verify their performance, and improve testing efficiency and accuracy.
Smart Images
Figure CN121783467A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of airtightness testing fixtures, and more specifically, to an airtightness testing device. Background Technology
[0002] The shut-off valve used on high-speed trains is a manual valve used to cut off or open specific air circuits in the braking system. It is an important safety component of the train braking system, directly related to the normal operation of the braking function and fault isolation. For example, when the train's braking fails to release due to various reasons or when maintenance is required, the shut-off valve needs to be operated.
[0003] Air tightness is one of the core performance indicators of the shut-off valve, directly determining whether it can effectively achieve the function of "cutting off / opening the air passage". Once the air tightness fails, the shut-off valve will lose its control function and may even cause braking system failure. The shut-off valve of the EMU is in direct contact with the external environment, and temperature has a significant impact on the air tightness of the shut-off valve. Summary of the Invention
[0004] The purpose of this invention is to provide an airtightness testing device that can simulate the airtightness changes of a shut-off gate under different temperature environments.
[0005] To achieve the above objectives, the present invention provides the following technical solution: An airtightness testing device for testing the airtightness performance of airtight products includes a temperature change test chamber, a pressure measuring device, an air cylinder, a sample connecting pipe, and an air pressure source. The air cylinder is located inside the temperature change test chamber, while the air pressure source and the pressure measuring device are located outside the temperature change test chamber; the interior of the temperature change test chamber is configured to accommodate the airtight product. One end of the sample connecting pipe is configured to connect to the inlet of the air cylinder and to the airtight product; the other end of the sample connecting pipe extends out of the temperature change test chamber and is connected to the air pressure source; the outlet pipe of the air cylinder is in a blocked state to form a closed pressure-bearing space. The outlet pipe of the air cylinder extends out of the temperature change test chamber and is equipped with the pressure measuring device, or the pressure measuring device is installed between the air pressure source and the sample connecting pipe.
[0006] In any of the above technical solutions, optionally, the pressure measuring device includes multiple pressure sensors; the air cylinder, the pressure sensors, and the sample connecting pipe form a test assembly; the number of test assemblies is multiple, and each group of test assemblies is configured to connect to one of the airtight products; the pressure sensor, the air cylinder, the airtight product, and the sample connecting pipe are connected in sequence, or the air cylinder, the airtight product, the sample connecting pipe, and the pressure sensor are connected in sequence; The airtightness testing device also includes a multi-way diverter valve; the outlet of the air pressure source is connected to the inlet of the multi-way diverter valve; each set of the test components is connected to one of the outlets of the multi-way diverter valve.
[0007] In any of the above technical solutions, optionally, each outlet of the multi-way diverter valve is sequentially connected to a manual shut-off valve and an electrically controlled valve between each group of the test components; A pressure regulating valve is connected between the air pressure source and the multi-way diversion valve; In any of the above technical solutions, optionally, the electrically controlled valve is an electrically controlled proportional valve or a switching valve; Optionally, in any of the above technical solutions, the pressure sensor is a high-precision pressure sensor; the resolution of the high-precision pressure sensor is not less than 0.01 kPa.
[0008] Optionally, in any of the above technical solutions, the airtightness testing device further includes a control device; the temperature change test chamber, the air cylinder, the air pressure source and the pressure measuring device are respectively electrically connected to the control device.
[0009] Optionally, in any of the above technical solutions, the inner wall of the temperature change test chamber is made of stainless steel. Optionally, in any of the above technical solutions, the inner wall of the temperature change test chamber is lined with high-performance thermal insulation material; In any of the above technical solutions, optionally, the temperature change test chamber is equipped with a forced air circulation system and a temperature changing device; the forced air circulation system and the temperature changing device are respectively electrically connected to the control device; The temperature-changing device includes a compressor refrigeration system and an electric heater system; the compressor refrigeration system and the electric heater system are respectively electrically connected to the control device; The temperature change test chamber is equipped with multiple temperature sensors and multiple humidity sensors. All temperature sensors and all humidity sensors are electrically connected to the control device. The temperature sensors are configured to detect the temperature inside the temperature change test chamber and send the temperature information to the control device. The humidity sensors are configured to detect the humidity inside the temperature change test chamber and send the humidity information to the control device. The control device receives the temperature information and the humidity information and controls the start and stop of the forced air circulation system, the compressor refrigeration system, and the electric heater system accordingly.
[0010] Optionally, in any of the above technical solutions, the control device and the pressure measuring device are integrated in a control box, and the control box is located outside the temperature change test chamber.
[0011] In any of the above technical solutions, optionally, the airtightness testing device further includes a support frame disposed inside the temperature change test chamber; the support frame includes a frame body, a mounting rail and a mounting plate; the mounting rail and the mounting plate are both fixedly connected to the upper part of the frame body; The air cylinder is configured to be movably connected to the mounting rail and can be locked to the mounting rail, and the mounting plate is configured to be fixedly connected to the airtight product.
[0012] In any of the above technical solutions, optionally, the air cylinder is fitted with a clamp, and bolts are connected to both ends of the clamp. The bolts pass through the clamp and the mounting guide rail in sequence and are fastened to the nut to lock the air cylinder on the mounting guide rail; the mounting guide rail is provided with a sliding groove for the bolts to slide. In any of the above technical solutions, the mounting plate may optionally be plate-shaped, L-shaped, or U-shaped; In any of the above technical solutions, optionally, the mounting plate is connected to a clamp for clamping the airtight product, or the mounting plate is provided with threaded holes for fixing the airtight product. Optionally, in any of the above technical solutions, the frame is made of welded steel sections.
[0013] Optionally, in any of the above technical solutions, the air pressure source includes a high-pressure air compressor or an integrated pressure source.
[0014] Optionally, in any of the above technical solutions, the adjustable temperature inside the temperature change test chamber is between -50°C and 50°C. The pressure resistance of the air cylinder and the pressure measuring device is not less than 1000 kPa.
[0015] The main beneficial effects of this invention are: The airtightness testing device provided by this invention is used to test the airtightness performance of airtight products such as shut-off valves. It includes a temperature change test chamber, a pressure measuring device, a cylinder, a sample connecting pipe, and a pressure source. The pressure source provides a stable gas supply; the cylinder stores low-temperature gas, ensuring the low-temperature performance of the working gas in the airtight product; the pressure measuring device monitors the pressure value of the pipeline where the airtight product is located; and the temperature change test chamber and pressure measuring device can simulate the airtightness changes of the airtight product at the switch position under high and low temperature environments or temperature change environments. The pressure value changes provided by the pressure measuring device can be used to determine the airtightness changes of the airtight product under different temperature environments. This device can be used to analyze, improve, and optimize the internal structure of the airtight product and verify its performance.
[0016] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 This is a schematic diagram of a first structure of the airtightness testing device provided in an embodiment of the present invention; Figure 2 for Figure 1 Top view of the airtightness testing apparatus shown; Figure 3 This is a schematic diagram of a second structure of the airtightness testing device provided in an embodiment of the present invention; Figure 4 for Figure 3 The top view of the airtightness testing apparatus shown.
[0019] Icons: 1-Temperature change test chamber; 2-Pressure measuring device; 3-Support frame; 4-Air cylinder; 5-Sample connecting pipe; 6-Air pressure source; 7-Airtight product; 8-Multi-way diverter valve. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0021] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0022] It should be noted that similar labels 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.
[0023] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0024] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0025] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0026] The shut-off valve used on high-speed trains is a manual valve used to cut off or open specific air circuits in the braking system. It is an important safety component of the train braking system, directly related to the normal operation of the braking function and fault isolation. For example, when the train brakes fail to release or maintenance is required due to various reasons, the shut-off valve needs to be operated.
[0027] Air tightness is one of the core performance indicators of a shut-off valve, directly determining its ability to effectively "cut off / open the air passage." If air tightness fails, the shut-off valve will lose its control function and may even cause braking system failure. The shut-off valves of high-speed trains are in direct contact with the external environment, and temperature has a significant impact on their air tightness. To simulate the temperature effect on the shut-off valve, the air tightness testing device described in this embodiment is designed. This air tightness testing device can be used to test the air tightness of high-speed train shut-off valves, and can also be used for other air tightness products, especially those operating in low-temperature environments. It can simulate the air tightness changes of the shut-off valve in a pressurized state under high and low temperature environments or temperature variations. It can record the air tightness changes of the shut-off valve at different temperatures in real time, and can be used to analyze, improve, and optimize the internal structure of the shut-off valve, and verify its performance.
[0028] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0029] See Figures 1-4 As shown, the airtightness testing device provided in this embodiment is used to test the airtightness performance of the airtightness product 7. The airtightness product 7 is, for example, a shut-off valve or similar product.
[0030] The airtightness testing device includes a temperature change test chamber 1, a pressure measuring device 2, an air cylinder 4, a sample connecting pipe 5, and an air pressure source 6.
[0031] The air cylinder 4 is located inside the temperature change test chamber 1, while the air pressure source 6 and pressure measuring device 2 are located outside the temperature change test chamber 1. The interior of the temperature change test chamber 1 is configured to accommodate the airtight product 7. By placing the air pressure source 6 and pressure measuring device 2 outside the temperature change test chamber 1, rather than inside it, the technical requirements for the air pressure source 6 and pressure measuring device 2 can be reduced. This reduces the cost of the air pressure source 6 and pressure measuring device 2 while ensuring the normal operation of the airtightness test device, and also guarantees the working accuracy of the air pressure source 6 and pressure measuring device 2.
[0032] One end of the sample connecting pipe 5 is connected to the inlet of the air cylinder 4 to the airtight product 7; the other end of the sample connecting pipe 5 extends out of the temperature change test chamber 1 and is connected to the air pressure source 6. The outlet pipe of the air cylinder 4 is in a blocked state to form a closed pressure space, which facilitates the airtightness test of the airtight product 7.
[0033] The outlet pipe of the air cylinder 4 extends out of the temperature change test chamber 1 and is equipped with a pressure measuring device 2, or a pressure measuring device 2 is installed between the air pressure source 6 and the sample connecting pipe 5. That is, as Figure 1As shown, the air pressure source 6, sample connecting pipe 5, airtight product 7, air cylinder 4, and pressure measuring device 2 are connected in sequence, or as shown in the diagram. Figure 3 As shown, the air pressure source 6, pressure measuring device 2, sample connecting pipe 5, airtight product 7, and air cylinder 4 are connected in sequence. Through the pressure measuring device 2, the airtightness change of the airtight product 7, such as the shut-off valve, can be monitored in the inflated state. The airtightness change of the airtight product 7 at different temperatures can be recorded in real time. This can be used to analyze, improve, and optimize the internal structure of the airtight product 7 and verify its performance.
[0034] Optionally, the temperature inside the temperature change test chamber 1 is adjustable to provide different temperature environments for testing the airtightness of the product 7.
[0035] In some embodiments, when the airtight product 7 is a shut-off valve, the air cylinder 4 is a compressed air storage container, which stabilizes the air pressure and stores the air source. The air cylinder 4 can ensure the low-temperature performance of the working gas when the shut-off valve is filled.
[0036] Optionally, the airtightness testing device further includes a support frame 3, which is installed inside the temperature change test chamber 1. The air cylinder 4 is connected to the support frame 3, and the support frame 3 is configured to fix the airtightness product 7. The air cylinder 4 and the airtightness product 7 are connected in a good supporting manner through the support frame 3.
[0037] The airtightness testing device described in this embodiment is used to test the airtightness performance of airtight products 7 such as shut-off valves. It includes a temperature change test chamber 1, a pressure measuring device 2, a blower 4, a sample connecting pipe 5, and a pressure source 6. The pressure source 6 provides stable gas; the blower 4 stores low-temperature gas, ensuring the low-temperature performance of the working gas of the airtight product 7; the pressure measuring device 2 monitors the pressure value of the pipeline where the airtight product 7 is located; the temperature change test chamber 1 and the pressure measuring device 2 can simulate the airtightness changes of the airtight product 7 in the switch position under high and low temperature environments or temperature change environments. The pressure value change provided by the pressure measuring device 2 can be used to determine the airtightness changes of the airtight product 7 under different temperature environments, which can be used to analyze, improve and optimize the internal structure of the airtight product 7 and verify the performance of the airtight product 7.
[0038] See Figures 1-4 As shown, in the optional embodiment, the pressure measuring device 2 includes multiple pressure sensors. The air cylinder 4, pressure sensors, and sample connecting pipe 5 form a test assembly. There are multiple test assemblies, and each set of test assemblies is configured to connect to one airtight product 7. Within a single test assembly, such as... Figure 4 As shown, the pressure sensor, sample connecting pipe 5, airtight product 7, and air cylinder 4 of the pressure measuring device 2 are connected in sequence, or as shown in the diagram. Figure 2 As shown, the sample connecting pipe 5, the airtight product 7, the air cylinder 4, and the pressure sensor of the pressure measuring device 2 are connected in sequence. That is, as... Figure 4 As shown, the air pressure source 6, the multi-way diverter valve 8, the pressure sensor of the pressure measuring device 2, the sample connecting pipe 5, the airtight product 7, and the air cylinder 4 are connected in sequence, or as shown in the diagram. Figure 2 As shown, the pressure source 6, the multi-way diversion valve 8, the sample connecting pipe 5, the airtight product 7, the air cylinder 4, and the pressure sensor of the pressure measuring device 2 are connected in sequence.
[0039] The airtightness testing device also includes a multi-way diverter valve 8; the outlet of the pressure source 6 is connected to the inlet of the multi-way diverter valve 8, and each set of test components is connected to one of the outlets of the multi-way diverter valve 8. Optionally, the number of test components and the number of pressure sensors correspond to the number of outlets of the multi-way diverter valve 8.
[0040] In this embodiment, the airtightness testing device uses a multi-way diverter valve 8, which can realize synchronous and parallel testing of multiple airtightness products 7, greatly improving the testing efficiency.
[0041] In an optional embodiment, each outlet of the multi-way diverter valve 8 is sequentially connected to a manual shut-off valve and an electrically controlled valve between each group of test components. The manual shut-off valve allows for manual isolation of the test of that group of test components and facilitates the installation, disassembly, and maintenance of the airtight product 7. The electrically controlled valve allows for precise control of the gas flow rate and on / off state of the gas supplied to the airtight product 7 in that group of test components.
[0042] Optionally, the electrically controlled valve may be an electrically controlled proportional valve or an on / off valve, or other valves.
[0043] Optionally, a pressure regulating valve is connected between the air pressure source 6 and the multi-way diverter valve 8; the pressure regulating valve can make the gas pressure output by the air pressure source 6 more stable, and the airflow more stable, which is beneficial for the airtightness product 7 test.
[0044] Optionally, the pressure sensor is a high-precision pressure sensor or other pressure sensor.
[0045] Optionally, the high-precision pressure sensor has a resolution of not less than 0.01 kPa.
[0046] In an optional embodiment, the airtightness testing device further includes a control device; the temperature change test chamber 1, the air cylinder 4, the air pressure source 6, and the pressure measuring device 2 are all electrically connected to the control device. The electrical connection between the temperature change test chamber 1 and the control device allows the control device to receive temperature and humidity information from the temperature change test chamber 1, and also allows the temperature change test chamber 1 to receive instructions from the control device to change the temperature and humidity values within the temperature change test chamber 1. The electrical connection between the air cylinder 4 and the control device allows the control device to control the on / off state of the air cylinder 4. The electrical connection between the air pressure source 6 and the control device allows the control device to control the pressure output by the air pressure source 6. The electrical connection between the pressure measuring device 2 and the control device allows the control device to receive the pressure values monitored by the pressure measuring device 2.
[0047] In an optional embodiment, the inner wall of the temperature change test chamber 1 is made of stainless steel or other materials.
[0048] In an optional embodiment, the inner wall of the temperature change test chamber 1 is lined with high-performance thermal insulation material to maintain the temperature inside the temperature change test chamber 1.
[0049] In an optional embodiment, the temperature change test chamber 1 is equipped with a forced air circulation system and a temperature control device; the forced air circulation system and the temperature control device are electrically connected to a control device; the forced air circulation system ensures uniform temperature within the temperature change test chamber 1; the temperature control device changes the temperature within the temperature change test chamber 1.
[0050] Optionally, the temperature-changing device includes a compressor refrigeration system and an electric heater system; the compressor refrigeration system and the electric heater system are electrically connected to the control device, so that the compressor refrigeration system and the electric heater can work under the control of the control device, and thus the temperature-changing device can work under the control of the control device.
[0051] In an optional embodiment, the temperature change test chamber 1 is equipped with multiple temperature sensors and multiple humidity sensors. All temperature and humidity sensors are electrically connected to a control device. The temperature sensors are configured to detect the internal temperature of the test chamber and send the temperature information to the control device. The humidity sensors are configured to detect the internal humidity of the test chamber and send the humidity information to the control device. The control device receives the temperature and humidity information and accordingly controls the start and stop of the forced air circulation system, the compressor refrigeration system, and the electric heater system. By setting multiple temperature and humidity sensors, the temperature and humidity inside the temperature change test chamber 1 can be better monitored. The electrical connection of all temperature and humidity sensors to the control device allows for real-time transmission of temperature and humidity signals. This enables the control device to control the start and stop of the forced air circulation system, the compressor refrigeration system, and the electric heater system based on the received temperature and humidity information, forming a closed-loop control system. This achieves precise temperature and humidity control and allows for programmed temperature control according to a set temperature change rate.
[0052] Optionally, multiple temperature sensors and multiple humidity sensors are evenly distributed inside the temperature change test chamber 1.
[0053] In an optional embodiment, the control device and pressure measuring device 2 are integrated into a control box, which is located outside the temperature change test chamber 1. Integrating the control device and pressure measuring device 2 into the control box facilitates assembly and disassembly.
[0054] In an optional embodiment, the support frame 3 includes a frame body, mounting rails, and mounting plates; both the mounting rails and mounting plates are fixedly connected to the upper part of the frame body. The mounting rails and mounting plates enable modular mounting of products such as the air cylinder 4 and the airtight product 7.
[0055] In an optional embodiment, the air cylinder 4 is configured to be movably connected to the mounting rail, and the air cylinder 4 can be locked onto the mounting rail to fix the air cylinder 4 to the mounting rail. For example, the air cylinder 4 is covered with a clamp, and bolts are connected to both ends of the clamp. The bolts pass through the clamp and the mounting rail in sequence and are fastened with nuts to lock the air cylinder 4 onto the mounting rail; the mounting rail is provided with a sliding groove for the bolts to slide. In some embodiments, the air cylinder 4 can also be fixedly connected to the mounting rail in other ways.
[0056] In an optional embodiment, the mounting plate is configured to fix the airtight product 7. For example, the mounting plate is equipped with a clamp for clamping the airtight product 7, or the mounting plate is provided with threaded holes for fixing the airtight product 7, or other methods are used to fix the airtight product 7.
[0057] In the optional embodiments of this example, the mounting plate is plate-shaped, L-shaped, U-shaped, or other shapes.
[0058] In an optional embodiment, the frame is constructed by welding structural steel. In some embodiments, the frame can be formed in other ways, such as by connecting steel members with screws.
[0059] In some embodiments, the support frame 3 serves as the mounting base for the entire airtightness testing device. The frame is welded from structural steel, providing sufficient rigidity and stability. The upper part of the support frame 3 is equipped with modular mounting rails and quick-change mounting plates for securing the air cylinder 4, piping, and the airtightness product 7 to be tested, such as the shut-off valve. The air cylinder 4 is fastened to its designated position on the support frame 3 using clamps and bolts; the shut-off valve is secured to the quick-change mounting plate via its own mounting flange or interface using clamps, ensuring its stable position and preventing loosening under temperature changes and pressure shocks.
[0060] In the optional embodiments of this example, the air pressure source 6 includes a high-pressure air compressor or an integrated pressure source, or other air pressure sources may be used.
[0061] In the optional embodiment, the adjustable temperature inside the temperature change test chamber 1 is between -50°C and 50°C.
[0062] In an optional embodiment, the pressure resistance of the air cylinder 4 and the pressure measuring device 2 is not less than 1000 kPa. Optionally, the pressure resistance of the airtightness testing device is not less than 1000 kPa.
[0063] The airtightness testing device provided in this embodiment is a highly automated and integrated testing platform, and its core advantage is: 1. Realistic Environment Simulation: The temperature change test chamber can accurately simulate the extreme high and low temperatures and temperature cycling conditions that airtight products such as cut-off valves may encounter in actual operation.
[0064] 2. High-efficiency parallel testing: Based on the mounting rails and mounting plates of the support frame 3, products such as air cylinders 4 and airtight products 7 are installed in a modular manner; based on the multiple air path design of the multi-way diversion valve 8, multiple airtight products 7 such as shut-off plugs can be tested synchronously and in parallel, which greatly improves the testing efficiency.
[0065] 3. High Precision and Automation: The integrated control system for the temperature change test chamber 1, air cylinder 4, air pressure source 6, and pressure measuring device 2 enables complete automation of the testing process, eliminating human error. High-precision pressure sensors ensure the accuracy and reliability of pressure data.
[0066] 4. Comprehensive testing capabilities: It can accurately test the airtightness of airtight products 7 such as shut-off valves in both the open position (i.e., the airtight product 7 is placed in the open pipeline position) and the closed position (i.e., the airtight product 7 is placed in the closed pipeline position).
[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. An airtightness testing device for detecting the airtightness performance of airtight products, characterized in that, Includes a temperature change test chamber, pressure measuring device, air cylinder, sample connecting pipe, and air pressure source; The air cylinder is located inside the temperature change test chamber, while the air pressure source and the pressure measuring device are located outside the temperature change test chamber; the interior of the temperature change test chamber is configured to accommodate the airtight product. One end of the sample connecting pipe is configured to connect to the inlet of the air cylinder and to the airtight product; the other end of the sample connecting pipe extends out of the temperature change test chamber and is connected to the air pressure source; the outlet pipe of the air cylinder is in a blocked state to form a closed pressure-bearing space. The outlet pipe of the air cylinder extends out of the temperature change test chamber and is equipped with the pressure measuring device, or the pressure measuring device is installed between the air pressure source and the sample connecting pipe.
2. The airtightness testing device according to claim 1, characterized in that, The pressure measuring device includes multiple pressure sensors; the air cylinder, the pressure sensors, and the sample connecting pipe form a test assembly; there are multiple test assemblies, and each set of test assemblies is configured to connect to one of the airtight products; the pressure sensor, the air cylinder, the airtight product, and the sample connecting pipe are connected in sequence, or the air cylinder, the airtight product, the sample connecting pipe, and the pressure sensor are connected in sequence. The airtightness testing device also includes a multi-way diverter valve; the outlet of the air pressure source is connected to the inlet of the multi-way diverter valve; each set of the test components is connected to one of the outlets of the multi-way diverter valve.
3. The airtightness testing apparatus according to claim 2, characterized in that, Each outlet of the multi-way diverter valve is sequentially connected to a manual shut-off valve and an electrically controlled valve between each group of the test components. A pressure regulating valve is connected between the air pressure source and the multi-way diversion valve.
4. The airtightness testing apparatus according to claim 3, characterized in that, The electrically controlled valve is an electrically controlled proportional valve or an on / off valve; The pressure sensor is a high-precision pressure sensor; the resolution of the high-precision pressure sensor is not less than 0.01 kPa.
5. The airtightness testing apparatus according to claim 1, characterized in that, It also includes a control device; the temperature change test chamber, the air cylinder, the air pressure source and the pressure measuring device are respectively electrically connected to the control device.
6. The airtightness testing apparatus according to claim 5, characterized in that, The inner wall of the temperature change test chamber is lined with high-performance thermal insulation material; The temperature change test chamber is equipped with a forced air circulation system and a temperature control device; the forced air circulation system is electrically connected to the control device. The temperature-changing device includes a compressor refrigeration system and an electric heater system; the compressor refrigeration system and the electric heater system are respectively electrically connected to the control device; The temperature change test chamber is equipped with multiple temperature sensors and multiple humidity sensors. All temperature sensors and all humidity sensors are electrically connected to the control device. The temperature sensors are configured to detect the temperature inside the temperature change test chamber and send the temperature information to the control device. The humidity sensors are configured to detect the humidity inside the temperature change test chamber and send the humidity information to the control device. The control device receives the temperature information and the humidity information and controls the start and stop of the forced air circulation system, the compressor refrigeration system, and the electric heater system accordingly.
7. The airtightness testing apparatus according to claim 1, characterized in that, It also includes a support frame installed inside the temperature change test chamber; The support frame includes a frame body, mounting rails, and mounting plate; both the mounting rails and the mounting plate are fixedly connected to the upper part of the frame body. The air cylinder is configured to be movably connected to the mounting rail and can be locked to the mounting rail, and the mounting plate is configured to be fixedly connected to the airtight product.
8. The airtightness testing apparatus according to claim 7, characterized in that, The air cylinder is fitted with a clamp, and bolts are connected to both ends of the clamp. The bolts pass through the clamp and the mounting guide rail in sequence and are fastened to the nut to lock the air cylinder on the mounting guide rail. The mounting guide rail is provided with a sliding groove for the bolts to slide.
9. The airtightness testing apparatus according to claim 7, characterized in that, The mounting plate is plate-shaped, L-shaped, or U-shaped; The mounting plate is connected to a clamp for clamping the airtight product, or the mounting plate is provided with threaded holes for fixing the airtight product.
10. The airtightness testing apparatus according to claim 1, characterized in that, The pressure source includes a high-pressure air compressor or an integrated pressure source; The adjustable temperature inside the temperature change test chamber is between -50°C and 50°C. The pressure resistance of the air cylinder and the pressure measuring device is not less than 1000 kPa.