A performance testing device for a gasket

Abstract

This invention relates to the field of sealing component testing equipment technology, and discloses a performance testing device for sealing gaskets, including a bottom base, on which a rigid guide post and a lower test flange are fixedly connected. The top end of the rigid guide post is connected to a top frame. A servo drive mechanism of the top frame is connected to a hollow shaft, and a displacement transmission rod passes through the hollow shaft. The top end of the displacement transmission rod abuts against a dial indicator, and the bottom end abuts against an upper test flange. A convex spherical self-aligning pad at the bottom of the hollow shaft is movably fitted with a concave spherical self-aligning pad on the upper test flange. A high and low temperature environment test chamber is covered outside the lower test flange and connected to a dual-cavity differential pipeline equipped with a mass flow meter. This invention utilizes spherical sliding to automatically eliminate off-center loading, ensuring that the test load is applied vertically and uniformly. The internal and external separation transmission structure eliminates interference from equipment deformation and thermal expansion, improving displacement reading accuracy. Combined with multi-media pipelines, it achieves high-precision quantitative evaluation and testing of minute leakage rates under complex working conditions.

Description

Technical Field

[0001] This invention relates to the field of sealing component testing equipment technology, specifically to a performance testing device for sealing gaskets. Background Technology

[0002] In industries such as petrochemicals, nuclear power, and special equipment manufacturing, gaskets at flange connections are critical components of piping and container systems. In actual service, gaskets often operate under prolonged conditions of high temperature, low temperature, high pressure, and alternating gaseous and liquid media. If creep relaxation or seal failure occurs, it can lead to high-pressure media leakage, causing safety accidents and economic losses. Therefore, before being put into application, it is necessary to use specialized testing equipment to simulate actual working conditions and evaluate the gasket's compression rebound, creep relaxation, and leakage rate under different media.

[0003] Currently, the industry typically uses general-purpose material testing machines or basic flange clamping fixtures for mechanical and sealing tests of gaskets. These devices often employ hydraulic cylinders or basic lead screw assemblies for linear pressurization, featuring simple mechanical structures and easy operation. When conducting routine destructive tests or basic compression tests at room temperature, they can quickly apply clamping force and collect load data, offering advantages such as low equipment cost, easy daily maintenance, and suitability for large-scale sampling inspections in factory environments.

[0004] However, existing equipment has revealed several problems during high-precision and extreme condition simulation tests. Most existing equipment uses a rigid parallel downward loading method with upper and lower flanges. Due to inevitable tolerances in flange processing and assembly, rigid downward loading is prone to uneven loading, resulting in pressure that cannot be evenly distributed on the gasket surface, causing excessive local stress or side leakage. Furthermore, during high and low temperature tests, the displacement measurement and transmission components of the equipment are often integrated with the main load-bearing structure or directly exposed inside the temperature-controlled chamber. The mechanical deformation caused by heavy loading and the thermal expansion and contraction caused by environmental temperature differences will superimpose, severely affecting the accuracy of reading micron-level creep relaxation displacement. Moreover, traditional leakage detection mainly relies on volumetric measurement methods, but fluid volume is easily affected by fluctuations in chamber temperature and pipeline pressure, leading to significant deviations in the calculated leakage rate. Additionally, during alternating gas-liquid media tests, manual purging, disassembly, and reconnection of pipelines are often required, which is not only time-consuming and labor-intensive, but repeated disassembly and reassembly can also easily create new leakage points at the interfaces, making it difficult to accurately quantify minute leaks under complex conditions. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a performance testing device for sealing gaskets, which solves the problem of distortion in the measurement of micron-level displacement of gaskets and deviation in the calculation of the actual leakage rate caused by mechanical rigidity and uneven loading, interference from thermal expansion and contraction deformation, and the influence of temperature and pressure fluctuations on fluid volume in traditional testing equipment.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a performance testing device for sealing gaskets, comprising a bottom base, a rigid guide post fixedly connected to the bottom base, a top frame fixedly connected to the top of the rigid guide post, a lower test flange for supporting sealing gasket samples fixedly connected to the center of the bottom base, a servo drive mechanism mounted on the top frame, a hollow shaft connected to the servo drive mechanism, a displacement transmission rod passing through the hollow shaft, a dial indicator abutting the top of the displacement transmission rod, an upper test flange abutting the bottom of the displacement transmission rod, an avoidance slide assembly fixedly connected to the upper part of the top frame for adjusting the position of the dial indicator, a connecting plate connected to the bottom of the hollow shaft via a pressure sensor, a convex spherical self-aligning pad fixedly connected to the bottom of the connecting plate, a concave spherical self-aligning pad connected to the top surface of the upper test flange, and the convex spherical self-aligning pad movably connected within the concave spherical self-aligning pad.

[0007] Preferably, the avoidance slide assembly includes a guide rail, which is fixedly connected to the top frame. A movable frame is slidably connected to the outside of the guide rail. The dial indicator is installed in the movable frame. A groove is formed on the surface of the top frame, and the dial indicator is slidably connected in the groove.

[0008] Preferably, positioning holes are provided on both sides of the guide rail, and positioning heads are fixedly connected to both sides of the inner wall of the movable frame, with the positioning heads engaging inside the positioning holes.

[0009] Preferably, the servo drive mechanism includes a servo motor, the output end of which is fixedly connected to a lead screw, the lead screw is externally threaded to a ball screw, and the hollow shaft is mounted and connected to the ball screw.

[0010] Preferably, the concave spherical self-aligning pad has a mounting hole on its surface, and a miniature spring is fixedly connected in the mounting hole, with the top of the miniature spring abutting against the convex spherical self-aligning pad.

[0011] Preferably, a connecting rod is fixedly connected to the outside of the upper test flange, and a floating bushing is fixedly connected to the end of the connecting rod away from the upper test flange. The floating bushing is sleeved on the outside of the rigid guide post.

[0012] Preferably, the outer cover of the lower test flange is provided with a high and low temperature environment test chamber. The hollow shaft and the displacement transmission rod pass through the top of the high and low temperature environment test chamber. The surface of the high and low temperature environment test chamber has perforations with the same number and position as the connecting rods. An elastic sealing sheet is connected inside the perforation. The connecting rod is slidably connected inside the perforation, so that the perforation is sealed by the elasticity of the elastic sealing sheet itself.

[0013] Preferably, a dual-chamber differential pipeline is connected to the side of the lower test flange, and a microfluidic integrated valve is connected to the surface of the dual-chamber differential pipeline. One end of the dual-chamber differential pipeline is connected to a Y-shaped flexible tube, one end of the Y-shaped flexible tube is connected to a liquid storage tank, and the other end of the Y-shaped flexible tube is connected to a nitrogen cylinder.

[0014] Preferably, a differential pressure transmitter is connected to the surface of the dual-cavity differential pipeline, and the two ends of the differential pressure transmitter are respectively connected to the internal channels of the dual-cavity differential pipeline.

[0015] Preferably, a laser level sensor is connected to one end of the Y-shaped hose that connects to the liquid storage tank, and a mass flow meter is installed at the connection point between the other end of the Y-shaped hose and the nitrogen cylinder.

[0016] This invention provides a performance testing device for sealing gaskets. It has the following beneficial effects: 1. This invention features a convex spherical self-aligning pad at the bottom of a hollow shaft, which mates with a concave spherical self-aligning pad on the top surface of the upper test flange. A floating bushing fitted onto a rigid guide post is connected to the outside of the upper test flange. In the initial stage of applying the test load, the upper and lower flanges can automatically adjust through the sliding of the spherical surface, eliminating non-parallelism errors generated during assembly. At the same time, the rigid guide post can limit the horizontal deflection of the flange. This ensures that the test load can be applied vertically and uniformly to the surface of the sealing gasket, solving the problems of uneven local stress and side leakage caused by the rigid off-center load of the equipment.

[0017] 2. In this invention, a displacement transmission rod is inserted inside a hollow shaft, and a high and low temperature environment test chamber is set up outside the test area. While transmitting pressure downward, the hollow shaft also provides physical isolation for the internal displacement transmission rod. In addition, the displacement transmission rod is made of Invar steel with a low coefficient of thermal expansion, so that the displacement generated by the pressure on the gasket will not be affected by the deformation of the external loading components when it is transmitted upward. This eliminates the error caused by thermal expansion and contraction due to temperature changes in the test chamber, and ensures that the dial indicator can accurately read the compression and relaxation data of the gasket under extreme temperatures.

[0018] 3. This invention connects a dual-chamber differential pipeline to the side of the lower test flange, and configures a microfluidic integrated valve, mass flow meter, laser level sensor, and differential pressure transmitter on the pipeline system. The liquid storage tank and nitrogen cylinder are connected respectively through Y-shaped hoses. When performing gas-liquid dual testing, the frequent pipeline replacement is eliminated. During the test, the mass flow meter directly measures the change in fluid mass, avoiding the defects of traditional volume measurement that are easily affected by temperature and pressure. Combined with the gas-liquid interface displacement recorded by the laser level sensor and the differential pressure data monitored by the differential pressure transmitter, the leakage rate of the gasket in complex media environments can be accurately calculated. Attached Figure Description

[0019] Figure 1 This is an overall diagram of the gasket performance testing device of the present invention; Figure 2 This is a three-dimensional schematic diagram of the gasket test bench of the present invention; Figure 3 This is a schematic diagram showing the disassembled micrometer avoidance slide assembly of the present invention; Figure 4 for Figure 2 Enlarged view of point A in the middle; Figure 5 This is a schematic diagram of the clamping off-center load elimination structure of the present invention. Figure 6 for Figure 5 Enlarged view of section B in the middle.

[0020] The components include: 1. Bottom base; 2. Rigid guide post; 3. Top frame; 4. Lower test flange; 5. Upper test flange; 6. Servo drive mechanism; 601. Servo motor; 602. Lead screw; 603. Ball screw; 7. Hollow shaft; 8. Displacement transmission rod; 9. Pressure sensor; 10. Connecting plate; 11. Convex spherical self-aligning pad; 12. Concave spherical self-aligning pad; 13. Mounting hole; 14. Miniature spring; 15. 16. Dial indicator; 17. Guide rail; 18. Positioning hole; 19. Movable frame; 20. Positioning head; 21. Slide groove; 22. Connecting rod; 23. Floating bushing; 24. High and low temperature environment test chamber; 25. Elastic sealing sheet; 26. Liquid storage tank; 27. Nitrogen cylinder; 28. Y-shaped hose; 29. ​​Dual-chamber differential pipeline; 30. Microfluidic integrated valve; 31. Differential pressure transmitter; 32. Mass flow meter; 33. Laser level sensor. Detailed Implementation

[0021] The technical solutions in 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see the appendix Figure 1 -Appendix Figure 3 and attached Figure 5This invention provides a performance testing device for sealing gaskets, comprising a bottom base 1, a rigid guide post 2 fixedly connected to the bottom base 1, a top frame 3 fixedly connected to the top of the rigid guide post 2, a lower test flange 4 fixedly connected to the center of the bottom base 1 for carrying the sealing gasket sample, a servo drive mechanism 6 mounted on the top frame 3, a hollow shaft 7 connected to the servo drive mechanism 6, a displacement transmission rod 8 passing through the hollow shaft 7, a dial indicator 15 abutting the top of the displacement transmission rod 8, and an upper test flange 5 abutting the bottom of the displacement transmission rod 8; an avoidance slide assembly fixedly connected to the upper part of the top frame 3 for adjusting the position of the dial indicator 15, a connecting plate 10 connected to the bottom of the hollow shaft 7 via a pressure sensor 9, a convex spherical self-aligning pad 11 fixedly connected to the bottom of the connecting plate 10, a concave spherical self-aligning pad 12 connected to the top surface of the upper test flange 5, and the convex spherical self-aligning pad 11 movably connected within the concave spherical self-aligning pad 12.

[0023] The entire testing device is supported by the bottom base 1, ensuring the stability and reliability of the equipment during operation. The rigid guide column 2 on it works in conjunction with the upper test flange 5 to guide the linear movement, ensuring that the upper test flange 5 remains absolutely vertical and does not deviate when moving up and down. The top frame 3 on top of the rigid guide column 2 is used to support the upper drive components and provide reaction force support to avoid structural deformation of the equipment when loading with large tonnage. The lower test flange 4 at the bottom is used to place the sealing gasket sample and provides a high-rigidity support bearing surface at the bottom. The servo drive mechanism 6 at the top adopts a closed-loop system composed of a servo motor 601, a lead screw 602 and a ball screw 603 to provide high-precision, large-tonnage automated vertical loading force, accurately control the flange clamping force applied to the gasket, and solve the problems of slow manual loading and uneven force distribution. The driving force is transmitted to the hollow shaft 7. While transmitting a huge thrust, the hollow shaft 7 provides protection and isolation space for the internal displacement transmission rod 8, avoiding interference with the independent measurement of internal displacement when transmitting the load. The internal displacement transmission rod 8 is made of Invar alloy to maintain zero thermal expansion characteristics. It is responsible for transmitting the micron-level compression or creep relaxation displacement of the gasket without loss, eliminating the interference of thermal expansion and contraction caused by temperature on the data. The external pressure sensor 9 monitors the load transmitted by the hollow shaft 7 in real time and provides feedback signals to the servo drive mechanism 6 to realize automatic pressure holding and relaxation compensation. The dial indicator 15 is used to read the small displacement transmitted by the displacement transmission rod 8 with high precision. The upper test flange 5 and the lower test flange 4 are subjected to a pressing movement to uniformly apply flange surface pressure to simulate the sealing state under real working conditions. The clearance slide assembly on the upper part of the equipment is used to adjust the position of the dial indicator 15, so that the dial indicator 15 can safely retreat when the equipment is loading or unloading or moving with a large stroke, avoiding mechanical interference and damage; the connecting plate 10 at the bottom of the hollow shaft 7 is used to securely connect the self-aligning assembly below, ensuring a vertical and smooth transition of the load force; finally, the convex spherical self-aligning pad 11 and the concave spherical self-aligning pad 12 perform a small sliding and deflection movement, which automatically eliminates the micron-level non-parallelism between the upper and lower flanges in the early stage of loading, ensuring that the load is absolutely vertical and evenly applied to the entire surface of the gasket, and completely eliminating the side leakage risk caused by rigid off-center loading.

[0024] Please see the appendix Figure 3 and attached Figure 4 The avoidance slide assembly includes a guide rail 16, which is fixedly connected to the top frame 3. A movable frame 18 is slidably connected to the outside of the guide rail 16. A dial indicator 15 is installed in the movable frame 18. A slide groove 20 is opened on the surface of the top frame 3, and the dial indicator 15 is slidably connected in the slide groove 20.

[0025] The guide rail 16 uses a metal linear guide rail to provide precise linear guidance, providing a movement trajectory for the upper test flange 5 and ensuring the stability of the lifting and avoidance action; the movable frame 18 cooperates with the guide rail 16 to perform linear sliding movement, thereby driving the dial indicator 15 to move within the slide groove 20, so that the dial indicator 15 no longer obstructs the displacement transmission rod 8, restricting the lifting and lowering of the upper test flange 5, and avoiding mechanical interference and collision damage with the lower lifting structure when the equipment is opened to load and unload the gasket; at the same time, the slide groove 20 on the surface of the frame provides avoidance and passage space for the vertical movement of the dial indicator 15, avoiding the frame body from obstructing its displacement stroke.

[0026] Please see the appendix Figure 3 and attached Figure 4 The guide rail 16 has positioning holes 17 on both sides, and the movable frame 18 has positioning heads 19 fixedly connected to both sides of the inner wall. The positioning heads 19 are engaged with the inside of the positioning holes 17.

[0027] The positioning holes 17 on both sides of the guide rail provide a precise locking position for the positioning head 19, ensuring that the movable frame 18 can stably stay in the set working position after moving left and right, avoiding slippage that would affect the test accuracy. The positioning head 19 on the inner wall of the movable frame 18 is made of high-strength elastic steel pin material to provide elastic locking and restoring force. When the movable frame 18 reaches the specified height, it automatically embeds into the positioning hole 17, realizing rapid locking of the movable frame 18 and its internal dial indicator 15. The positioning head 19 cooperates with the positioning hole 17 to perform locking movement, firmly fixing the dial indicator 15 at the absolute measurement height, ensuring the stability and reliability of displacement data reading during the test.

[0028] Please see the appendix Figure 1 and attached Figure 2The servo drive mechanism 6 includes a servo motor 601, the output end of which is fixedly connected to a lead screw 602, and the lead screw 602 is externally threaded to a ball screw 603. The hollow shaft 7 is installed and connected to the ball screw 603.

[0029] The servo motor 601 uses a high-torque AC servo motor to provide a precise and controllable rotational power source. It accurately outputs torque and speed according to the instructions of the control system, providing a stable and accurate initial power input for the subsequent flange pressurization action. The lead screw 602 at its output end is used to extend and transmit the rotational power downward, avoiding power loss during transmission. The ball screw 603 outside the lead screw 602 works with the lead screw 602 to perform helical transmission motion, efficiently and with low friction converting the rotational motion of the servo motor 601 into vertical linear thrust. Finally, the hollow shaft 7 works with the ball screw 603 to perform vertical downward linear motion, smoothly transmitting the converted huge linear thrust to the test component below, realizing the automated loading of the gasket.

[0030] Please see the appendix Figure 5 and attached Figure 6 The surface of the concave spherical self-aligning pad 12 is provided with a mounting hole 13, and a miniature spring 14 is fixedly connected in the mounting hole 13. The top of the miniature spring 14 abuts against the convex spherical self-aligning pad 11.

[0031] Mounting hole 13 provides built-in receiving and positioning space for miniature spring 14, preventing lateral slippage or bending failure of miniature spring 14 under pressure, and ensuring stable release of elastic force. The internal miniature spring 14 is made of spring steel with high fatigue limit to provide durable elastic support force. In the unloaded state, it lifts the convex spherical self-aligning pad 11 upward, keeping a small gap between the upper and lower spherical surfaces, reducing the frictional resistance in the initial alignment sliding. Finally, the miniature spring 14 cooperates with the convex spherical self-aligning pad 11 to perform elastic reset movement. After the test is unloaded, it automatically pushes the deflected convex spherical self-aligning pad 11 back to the horizontal initial centering state, providing a standard initial position for self-alignment in the next test, thereby improving the work efficiency of continuous testing.

[0032] Please see the appendix Figure 1 Appendix Figure 2 and attached Figure 5 A connecting rod 21 is fixedly connected to the outside of the upper test flange 5. A floating bushing 22 is fixedly connected to the end of the connecting rod 21 away from the upper test flange 5. The floating bushing 22 is sleeved on the outside of the rigid guide post 2.

[0033] The connecting rod 21 on the outside of the upper test flange 5 is used to connect the upper test flange 5 to the external guide structure, thereby preventing the upper test flange 5 from rotating or shifting horizontally during its up-and-down movement and self-alignment, ensuring the stability of the test posture. The floating bushing 22 at the end of the connecting rod 21 is made of wear-resistant metal material with an internal self-lubricating coating to provide low-friction sliding guidance. While transmitting vertical guiding force, it provides a certain radial floating clearance to avoid the phenomenon of up-and-down guide jamming caused by machining and assembly errors or micro-deformation of the equipment under stress, ensuring the smoothness of the loading process. Finally, the floating bushing 22 cooperates with the rigid guide post 2 to perform low-resistance vertical linear sliding motion, which can guide the upper test flange 5 to rise and fall smoothly, and also allow it to follow the self-aligning pad to make micron-level posture adjustments, further improving the uniformity of the force on the sealing gasket.

[0034] Please see the appendix Figure 1 The outer cover of the lower test flange 4 is equipped with a high and low temperature environment test chamber 23. The hollow shaft 7 and the displacement transmission rod 8 pass through the top of the high and low temperature environment test chamber 23. The surface of the high and low temperature environment test chamber 23 has perforations with the same number and position as the connecting rod 21. An elastic sealing sheet 24 is connected inside the perforation. The connecting rod 21 is slidably connected inside the perforation, so that the perforation is sealed by the elasticity of the elastic sealing sheet 24 itself.

[0035] The high and low temperature environment test chamber 23, which covers the lower test flange 4, is made of a metal box material with a heat insulation layer to provide a controllable extreme temperature test environment. It encloses the test flange and gasket sample in a closed, temperature-controlled space, thus simulating the extreme temperature conditions of the sealing gasket in a real industrial environment and ensuring the consistency of temperature test conditions. The hollow shaft 7 and displacement transmission rod 8 pass through the top of the high and low temperature environment test chamber 23. Perforations on the surface of the high and low temperature environment test chamber 23 provide a channel for external connection components to penetrate the chamber, ensuring the smooth operation of the drive components located outside the high and low temperature environment test chamber 23. The moving and guiding mechanism can smoothly connect to the internal structure of the high and low temperature environment test chamber 23; the elastic sealing sheet 24 connected inside the perforation is made of high and low temperature resistant silicone to provide deformation sealing and block the structural gap between the perforation and the moving parts, so as to prevent heat loss inside the high and low temperature environment test chamber 23 or the intrusion of external airflow; finally, the connecting rod 21 cooperates with the elastic sealing sheet 24 to perform a close sliding movement, which allows the connecting rod 21 to move freely up and down while maintaining the dynamic heat preservation of the equipment, so that the perforation can be reliably sealed under the elastic action of the elastic sealing sheet 24 itself.

[0036] Please see the appendix Figure 1 and attached Figure 2The lower test flange 4 is connected to a dual-chamber differential pipeline 28 on its side. Each surface of the dual-chamber differential pipeline 28 is connected to a microfluidic integrated valve 29. One end of the dual-chamber differential pipeline 28 is connected to a Y-shaped hose 27. One end of the Y-shaped hose 27 is connected to a liquid storage tank 25. The other end of the Y-shaped hose 27 is connected to a nitrogen cylinder 26.

[0037] The dual-cavity differential pipeline 28 connected to the side of the lower test flange 4 is made of high-pressure corrosion-resistant stainless steel to provide a safe channel for the delivery of high-pressure media. It independently introduces the test media into different cavities inside the test structure to avoid mixing of gas and liquid media, thereby ensuring the accuracy of differential pressure test data. The microfluidic integrated valve 29 connected to the pipeline surface is used to precisely control the on / off state and flow rate of the medium in the pipeline, avoiding the impact damage to the sealing gasket caused by excessive instantaneous air or liquid pressure, thus ensuring stable loading. It works with the dual-cavity differential pipeline 28 to throttle and cut off the medium movement, achieving precise pressure assurance inside the test flange.

[0038] The Y-shaped hose 27 connected to the end of the dual-chamber differential pipeline 28 guides the two different media sources to the main pipeline, avoiding frequent plugging and unplugging and pipeline replacement during gas-liquid dual testing, thus improving the efficiency of media switching. The liquid storage tank 25 connected to one end of the Y-shaped hose 27 is made of high-strength transparent resin material for safe storage and easy observation of liquid volume, providing a sufficient and stable hydraulic medium source for liquid sealing testing, avoiding test interruption due to insufficient liquid supply. The nitrogen cylinder 26 connected to the other end works with the Y-shaped hose 27 to carry out high-pressure gas delivery and injection, providing a stable, high-pressure and dry test gas source for the gasket gas sealing performance test.

[0039] Please see the appendix Figure 1 A differential pressure transmitter 30 is connected to the surface of the dual-chamber differential pipeline 28, and the two ends of the differential pressure transmitter 30 are respectively connected to the internal channels of the dual-chamber differential pipeline 28.

[0040] The differential pressure transmitter 30 connected to the surface of the dual-chamber differential pipeline 28 uses high-precision single-crystal silicon piezoresistive material to accurately sense minute pressure difference changes. It is used to monitor minute pressure fluctuations between the two pipelines in real time, avoiding test result errors caused by undetected minute leaks, and improving the accuracy of sealing performance evaluation. The two ends of the differential pressure transmitter 30 are respectively connected to the internal channels of the dual-chamber differential pipeline 28, and work with the dual-chamber differential pipeline 28 to collect and compare pressure signals in real time, ultimately achieving the effect of accurately calculating the leakage rate and dynamic sealing characteristics of the sealing gasket in complex media environments.

[0041] Please see the appendix Figure 1 A laser level sensor 32 is connected to one end of the Y-shaped hose 27 that connects to the liquid storage tank 25, and a mass flow meter 31 is installed at the other end of the Y-shaped hose 27 where it connects to the nitrogen cylinder 26.

[0042] The laser level sensor 32, connected to the storage tank 25 at one end of the Y-shaped hose 27, uses non-contact optical sensing technology for high-precision displacement and liquid level measurement. This is used to monitor the minute displacements of the gas-liquid interface inside the storage tank in real time during liquid or gas-liquid dual-medium testing, preventing test pressure instability due to undetected liquid level fluctuations and ensuring stable and controllable loading. The laser level sensor 32, in conjunction with the storage tank 25, performs dynamic interface tracking, enabling accurate quantitative assessment of minute leaks in the liquid medium. Simultaneously, the mass flow meter 31, connected to the nitrogen cylinder 26 and installed at the other end of the Y-shaped hose 27, uses non-contact optical sensing material for high-precision displacement and liquid level measurement. This is used to monitor the minute displacements of the gas-liquid interface inside the pipeline in real time during pneumatic or gas-liquid dual-medium testing, preventing test pressure instability due to undetected gas-liquid interface fluctuations and ensuring stable and controllable pneumatic loading. Finally, the mass flow meter 31, in conjunction with the nitrogen cylinder 26, performs dynamic flow monitoring and transmission, achieving accurate auxiliary calculation of medium consumption and airtightness under pneumatic driving conditions.

[0043] Working principle: The gasket to be tested is placed on the lower test flange 4. To prevent interference during loading and unloading, the movable frame 18 is slid along the guide rail 16 to allow the dial indicator 15 to retract to a safe position. After assembly, the movable frame 18 is reset, and the dial indicator 15 is fixed in the reference measurement position by engaging the positioning head 19 with the positioning hole 17. After the test starts, the servo motor 601 runs, and the power is converted into vertical thrust through the lead screw 602 and the ball screw 603, which drives the hollow shaft 7 to press down. In the initial stage of pressing down, the convex spherical self-aligning pad 11 under the connecting plate 10 produces a slight deflection in the concave spherical self-aligning pad 12, eliminating the slight non-parallelism error between the flanges. During this period, the connecting rod 21 on the side of the upper test flange 5 drives the floating bushing 22 to slide along the rigid guide post 2, restricting horizontal rotation, so that the load can be pressed vertically and evenly on the surface of the gasket.

[0044] During the loading and pressure holding stages, the high and low temperature environment test chamber 23 is opened to simulate the target test temperature; the elastic sealing sheet 24 at the perforation of the chamber wall allows the connecting rod 21 to move up and down while maintaining the seal; the pressure sensor 9 at the bottom of the hollow shaft 7 continuously monitors the load and feeds it back to the system for automatic compensation; since the displacement transmission rod 8 inside the hollow shaft 7 has an extremely low coefficient of thermal expansion of Invar steel, it eliminates the interference of ambient temperature, and can directly transmit the compression and relaxation displacement generated by the pressure on the gasket to the dial gauge 15 above the slide 20 for reading.

[0045] After reaching the set temperature and load parameters, the medium leakage test begins. The test medium is output from the liquid storage tank 25 or nitrogen cylinder 26, enters the dual-chamber differential pipeline 28 through the Y-shaped hose 27, and the microfluidic integrated valve 29 controls the injection of the medium into the inner cavity of the lower test flange 4 at the specified pressure and flow rate. During the test, the differential pressure transmitter 30 monitors the pressure difference fluctuation between the two pipelines. When conducting liquid tests, the laser level sensor 32 continuously tracks the minute displacement of the gas-liquid interface inside the liquid storage tank to achieve accurate assessment of minute leaks in the liquid medium. When conducting gas pressure or gas-liquid dual-medium tests, the mass flow meter 31 directly measures the mass flow rate of the gas medium, avoiding the influence of temperature and pressure on volume measurement. The system integrates the differential pressure, mass flow rate, and liquid level data to finally calculate the leakage rate of the gasket. After the test is completed, the equipment is unloaded, and the miniature spring 14 in the concave spherical surface pushes the convex spherical self-aligning gasket 11 back to the center position, resetting it for the next test.

Claims

1. A performance testing device for sealing gaskets, characterized in that, The system includes a bottom base (1), on which a rigid guide post (2) is fixedly connected. A top frame (3) is fixedly connected to the top of the rigid guide post (2). A lower test flange (4) for supporting the sealing gasket sample is fixedly connected to the center of the bottom base (1). A servo drive mechanism (6) is installed on the top frame (3). A hollow shaft (7) is connected to the servo drive mechanism (6). A displacement transmission rod (8) passes through the hollow shaft (7). A dial indicator (15) abuts at the top of the displacement transmission rod (8). The bottom end of the displacement transmission rod (8) abuts against the upper test flange (5). The upper part of the top frame (3) is fixedly connected to the clearance slide assembly, which is used to adjust the position of the dial indicator (15). The bottom end of the hollow shaft (7) is connected to the connecting plate (10) through the pressure sensor (9). The bottom of the connecting plate (10) is fixedly connected to the convex spherical self-aligning pad (11). The top surface of the upper test flange (5) is connected to the concave spherical self-aligning pad (12). The convex spherical self-aligning pad (11) is movably connected inside the concave spherical self-aligning pad (12).

2. The performance testing device for a sealing gasket according to claim 1, characterized in that, The avoidance slide assembly includes a guide rail (16), which is fixedly connected to the top frame (3). A movable frame (18) is slidably connected to the outside of the guide rail (16). The dial indicator (15) is installed in the movable frame (18). A groove (20) is opened on the surface of the top frame (3), and the dial indicator (15) is slidably connected in the groove (20).

3. The performance testing device for a sealing gasket according to claim 2, characterized in that, The guide rail (16) has positioning holes (17) on both sides, and the movable frame (18) has positioning heads (19) fixedly connected to both sides of the inner wall. The positioning heads (19) are engaged and connected inside the positioning holes (17).

4. The performance testing device for a sealing gasket according to claim 1, characterized in that, The servo drive mechanism (6) includes a servo motor (601), the output end of which is fixedly connected to a lead screw (602), and the lead screw (602) is externally threaded to a ball screw (603). The hollow shaft (7) is installed and connected to the ball screw (603).

5. The performance testing device for a sealing gasket according to claim 1, characterized in that, The concave spherical self-aligning pad (12) has an installation hole (13) on its surface. A miniature spring (14) is fixedly connected in the installation hole (13), and the top of the miniature spring (14) abuts against the convex spherical self-aligning pad (11).

6. The performance testing device for a sealing gasket according to claim 1, characterized in that, A connecting rod (21) is fixedly connected to the outside of the upper test flange (5). A floating bushing (22) is fixedly connected to one end of the connecting rod (21) away from the upper test flange (5). The floating bushing (22) is sleeved on the outside of the rigid guide post (2).

7. The performance testing device for a sealing gasket according to claim 6, characterized in that, The lower test flange (4) is covered with a high and low temperature environment test chamber (23). The hollow shaft (7) and the displacement transmission rod (8) pass through the top of the high and low temperature environment test chamber (23). The surface of the high and low temperature environment test chamber (23) has the same number and position as the connecting rod (21). An elastic sealing sheet (24) is connected inside the perforation. The connecting rod (21) is slidably connected inside the perforation, so that the perforation is sealed by the elasticity of the elastic sealing sheet (24).

8. The performance testing device for a sealing gasket according to claim 1, characterized in that, The lower test flange (4) is connected to a dual-chamber differential pipeline (28) on its side. Each of the surfaces of the dual-chamber differential pipeline (28) is connected to a microfluidic integrated valve (29). One end of the dual-chamber differential pipeline (28) is connected to a Y-shaped hose (27). One end of the Y-shaped hose (27) is connected to a liquid storage tank (25). The other end of the Y-shaped hose (27) is connected to a nitrogen cylinder (26).

9. The performance testing device for a sealing gasket according to claim 8, characterized in that, A differential pressure transmitter (30) is connected to the surface of the dual-cavity differential pipeline (28), and the two ends of the differential pressure transmitter (30) are respectively connected to the internal channels of the dual-cavity differential pipeline (28).

10. The performance testing device for a sealing gasket according to claim 8, characterized in that, A laser level sensor (32) is connected to one end of the Y-shaped hose (27) that connects to the liquid storage tank (25), and a mass flow meter (31) is installed at the other end of the Y-shaped hose (27) where it connects to the nitrogen cylinder (26).

Images