Flat valve with leak detection function

Abstract

The present application relates to the technical field of flat valve, and discloses a flat valve with leakage detection function, which comprises a valve body, a valve plate arranged in the valve body, valve seats attached to both sides of the valve plate, and a valve rod for driving the valve plate to move, wherein the valve seat comprises a leakage collection area on the inner side and a main sealing area on the outer side, the main sealing area is used for forming a main seal with the valve plate, and the leakage collection area comprises an annular collection groove arranged in the circumferential direction of the valve seat; an annular leakage collection cavity is arranged on the valve body, the leakage collection cavity is communicated with the annular collection groove through a first microchannel, and a detection interface communicated with the leakage collection cavity is arranged on the outer wall of the valve body; a leakage monitoring module is connected to the detection interface and used for detecting the leakage state of the medium entering the leakage collection cavity. The leakage medium is limited to flow in the preset collection path, direct entry into the cavity of the valve body or diffusion along the pipeline is avoided, the sensitivity and reliability of the leakage detection are improved, and the leakage monitoring module can continuously work in the online running state of the valve.

Description

Technical Field

[0001] This invention relates to the field of flat plate valve technology, and more specifically, to a flat plate valve with leakage detection function. Background Technology

[0002] Under long-term operating conditions, flat-plate valves are inevitably affected by factors such as media erosion, pressure fluctuations, temperature changes, and impurity entrainment. This inevitably leads to wear, scratches, or localized deformation of the sealing surface between the valve plate and seat, resulting in internal leakage. This type of internal leakage is typically well-hidden and initially involves small leaks. If not detected in time, it can cause media waste, environmental pollution, or even safety accidents. Therefore, effective monitoring of the sealing performance of flat-plate valves, especially the identification of early internal leakage, is of significant engineering importance.

[0003] In existing technologies, the testing methods for the sealing performance of flat valves mainly rely on shutdown testing or indirect judgment. For example, this involves periodically disassembling the valve to inspect the sealing surface, or conducting pressure holding tests while the system is shut down to determine if there are any leaks. While these methods can assess sealing performance to some extent, they generally suffer from drawbacks such as long testing cycles, high maintenance costs, and the need to interrupt system operation, making it difficult to meet the requirements for real-time monitoring of valve status under continuous operating conditions.

[0004] Therefore, it is necessary to propose a flat plate valve with leakage detection function to at least partially solve the problems existing in the prior art. Summary of the Invention

[0005] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] To at least partially solve the above problems, the present invention provides a flat plate valve with leakage detection function, including a valve body, a valve plate disposed within the valve body, valve seats attached to both sides of the valve plate, and a valve stem for driving the valve plate to move. The valve seat includes an inner leakage collection area and an outer main sealing area. The main sealing area is used to form a main seal with the valve plate. The leakage collection area includes an annular collection groove disposed along the circumference of the valve seat. An annular leakage collection cavity is disposed on the valve body. The leakage collection cavity is connected to the annular collection groove through a first microchannel. A detection interface connected to the leakage collection cavity is disposed on the outer wall of the valve body. The detection interface is connected to a leakage monitoring module for detecting the leakage status of the medium entering the leakage collection cavity.

[0007] Preferably, a flat plate valve with leakage detection function further includes an elastic element disposed between the valve seat and the valve body and located on the side away from the valve plate, for applying a pre-tightening force in the direction of the valve plate to maintain the valve seat and the valve plate in a fitted state.

[0008] Preferably, an isolation lip is provided at the opening of the annular collecting groove. The isolation lip is used to prevent the medium from directly entering the annular collecting groove under normal sealing conditions, and to guide the leaking medium across the isolation lip into the annular collecting groove when internal leakage occurs.

[0009] Preferably, the annular collecting groove is arranged in a continuous ring around the valve seat and has a V-shaped cross-section; multiple first microchannels are arranged evenly around the valve seat to guide the medium in the annular collecting groove to the leakage collecting cavity.

[0010] Preferably, two sealing rings are provided on both sides of the leakage collection cavity. The sealing rings are installed between the outer wall of the valve seat and the valve body, and the distance between the two sealing rings is greater than the inlet width of the leakage collection cavity, so as to block the direct communication between the valve body cavity and the leakage collection cavity.

[0011] Preferably, a leakage drainage assembly is provided at the bottom of the annular collecting tank, and the leakage drainage assembly includes the following components: The drainage cavity is located on the valve seat and communicates with the annular collecting groove and the first microchannel; A rotating plate is rotatably disposed within the drainage cavity. The rotating plate is configured as a fan-shaped plate, with its rotation center located at the center of the fan-shaped plate. A coil spring is provided at the connection between the rotating plate and the drainage cavity. The coil spring is used to ensure that the rotating plate always has a tendency to rotate in the direction of the annular collection groove. The drainage channel is set on the rotating plate and is used to intermittently connect the annular collection groove with the first microchannel during the rotation of the rotating plate.

[0012] Preferably, the leakage drainage assembly further includes the following components: The pressure relief channel is located on the rotating plate. Its inlet end is connected to the drainage channel, and its outlet end passes through the arc-shaped outer wall of the rotating plate. The inner wall of the drainage cavity is in intermittent contact with the outlet end of the pressure relief channel. The second microchannel is connected to the side of the drainage cavity, and its outlet end is unidirectionally connected to the valve body cavity. The third microchannel is connected to the side of the drainage cavity, and a pressure sensor is connected to its outlet end; the drainage cavity is provided with interfaces corresponding to the first microchannel, the second microchannel and the third microchannel in sequence along the depressurization rotation direction of the rotating plate.

[0013] Preferably, the leak monitoring module and the broadband ultrasonic transducer array connected to the detection interface together constitute a fluid acoustic impedance spectroscopy scanning system, which is configured as follows: The broadband ultrasonic transducer array is controlled to transmit a linear frequency-modulated scanning acoustic signal with continuously varying frequency into an acoustically closed cavity composed of a leakage collection cavity and an annular collection groove. An initial steady-state acoustic model is established using the reverberation signal generated by the reflection of a linear frequency modulated scanning acoustic signal between the metal cavity wall and the fluid interface of the valve body. The frequency response function of the acoustic closed cavity to the linear frequency-modulated scanning sound wave signal is acquired in real time, and the first resonant frequency point and the quality factor parameter corresponding to the width of the resonant peak are extracted from the frequency response function using the fast Fourier transform algorithm. The viscous damping coefficient of the fluid medium on the inner wall of the acoustic closed cavity is calculated based on the acoustic boundary layer theory. When the first resonant frequency is detected to shift towards lower frequencies and the quality factor parameter shows an exponential decay, it is determined that there is a high-viscosity liquid medium accumulating at the bottom of the acoustic closed cavity. When the first derivative of the resonance frequency and the second derivative of the quality factor parameter simultaneously satisfy the preset liquid loading characteristic matrix, a real internal leak is confirmed in the main sealing area and a leak alarm signal is triggered.

[0014] Preferably, a high-frequency piezoelectric stack actuator is coupled in series between the elastic element and the valve seat. The piezoelectric stack actuator is configured to apply micro-amplitude vibrations to the valve seat under the control of the leakage monitoring module. The leakage monitoring module is configured to execute a dynamic sealing control strategy based on micro-vibration signal injection. The dynamic sealing control strategy includes: By establishing a second-order dynamic equation that includes valve seat mass, sealing contact stiffness, and guide surface Coulomb friction, the static friction threshold during the axial feed process of the valve seat can be estimated in real time. A set of high-frequency sinusoidal disturbance signals with a frequency higher than the natural frequency of the mechanical system and an amplitude that can cause micron-level deformation is superimposed on the driving voltage of the piezoelectric stacked actuator. The inverse piezoelectric effect is used to induce micro-amplitude vibration in the ultrasonic frequency band between the valve seat and the valve body guide surface, so that the friction state of the contact interface is changed from macroscopic static friction to equivalent dynamic friction. While maintaining high-frequency micro-amplitude vibration, the DC bias component in the drive voltage is adaptively adjusted according to the real-time leakage amount, driving the valve seat to generate an axial displacement without overshoot towards the valve plate until the leakage characteristic signal detected by the leakage monitoring module disappears.

[0015] Preferably, the rotating plate includes several fluid cutting grids that are non-uniformly distributed circumferentially, causing pressure pulsation signals to be generated when the plate rotates under the drive of the leaking medium; the leak monitoring module is configured to execute mechanical fault self-diagnosis logic based on the pressure pulsation signals. When the leaking medium flows through the rotating, non-uniformly distributed fluid cutting grid, it generates a periodic on-off cutting effect on the fluid entering the leak collection cavity through the first microchannel, thereby superimposing a pressure pulsation signal with specific time-domain coding characteristics onto the fluid static pressure signal at the detection interface. The leakage monitoring module processes the collected pressure pulsation signals and demodulates the carrier frequency signal containing the real-time angular velocity information of the rotating plate and the duty cycle signal reflecting the flow channel on / off ratio. The demodulated carrier frequency signal is cross-correlated with the theoretical rotational speed calculated based on the fluid dynamics model. If the fluid static pressure is detected to be rising continuously but the corresponding carrier frequency component is missing in the pressure pulsation signal, or if the rate of change of the carrier frequency and the rate of increase of the fluid pressure do not conform to the linear relationship defined by Hooke's law of coiled springs, it is determined that mechanical jamming or failure of the elastic reset element has occurred inside the leakage drainage component.

[0016] Compared to existing technologies, this invention provides a flat plate valve with leakage detection functionality, offering at least the following advantages: By introducing a leakage collection area into the valve seat structure, and in conjunction with an annular collection groove, microchannels, and an independent leakage collection chamber, the leaking medium is confined to a preset collection path, preventing it from directly entering the valve body cavity or spreading along the pipeline, thus improving the sensitivity and reliability of leakage detection. The leakage monitoring module can operate continuously while the valve is in online operation, enabling real-time online monitoring of sealing performance without valve disassembly. This facilitates long-term monitoring and preventative maintenance of the valve's operating status, making it suitable for pipelines carrying high-risk media such as oil and gas, and chemicals, thereby enhancing system safety and intelligent operation and maintenance levels.

[0017] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a left half-sectional view of a flat plate valve with leakage detection function according to the present invention; Figure 2 This is a front half-sectional view of a flat plate valve with leakage detection function according to the present invention; Figure 3 For the present invention Figure 2 A magnified schematic diagram of the partial structure at point A in the middle; Figure 4 For the present invention Figure 3 A magnified schematic diagram of the structure at point B in the middle.

[0019] In the diagram: 1. Valve body; 2. Valve plate; 3. Valve seat; 4. Valve stem; 5. Annular collecting groove; 6. Isolation lip; 7. Leakage collecting cavity; 8. First microchannel; 9. Sealing ring; 10. Elastic element; 11. Drainage cavity; 12. Rotating plate; 13. Drainage channel; 14. Pressure relief channel; 15. Second microchannel; 16. Third microchannel; 17. Detection interface. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it based on the description.

[0021] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0022] Example 1: As Figures 1-4 As shown, the present invention provides a flat plate valve with leakage detection function, including a valve body 1, a valve plate 2 disposed within the valve body 1, valve seats 3 attached to both sides of the valve plate 2, and a valve stem 4 for driving the valve plate 2 to move. The valve seat 3 includes an inner leakage collection area and an outer main sealing area. The main sealing area is used to form a main seal with the valve plate 2. The leakage collection area includes an annular collection groove 5 disposed around the valve seat 3. An annular leakage collection cavity 7 is disposed on the valve body 1. The leakage collection cavity 7 is connected to the annular collection groove 5 through a first microchannel 8. A detection interface 17 connected to the leakage collection cavity 7 is disposed on the outer wall of the valve body 1. The detection interface 17 is connected to a leakage monitoring module for detecting the leakage status of the medium entering the leakage collection cavity 7.

[0023] The working principle and beneficial effects of the above technical solution are as follows: This embodiment provides a flat plate valve with leakage detection function. The valve stem 4 is connected to the handle through a drive assembly. By rotating the handle, the valve stem 4 is driven to move up and down, thereby moving the valve plate 2 up and down to realize the opening and closing of the valve.

[0024] The valve seat 3, along the direction of contact with the valve plate 2, forms a leakage collection area and a main sealing area sequentially from the inside to the outside. The main sealing area is equipped with a sealing ring, which forms the main sealing interface with the valve plate when the valve is normally closed, and is used to block the normal flow of the medium.

[0025] When the valve is closed and the main sealing area is well sealed, the medium is effectively blocked, and the leakage collection area does not participate in the medium flow. When internal leakage occurs in the main sealing area due to seal wear, impurity inclusion, or assembly deviation, a small amount of medium moves towards the leakage collection area along the tiny leakage channel between the valve plate 2 and the valve seat 3 under the action of pressure difference. After the leaking medium enters this area, it is actively collected in the annular collection groove 5 within the circumferential range, and will not randomly diffuse to other parts of the valve body.

[0026] Driven by its own pressure difference, the leaking medium in the annular collecting groove 5 enters the leak collecting chamber 7 through the first microchannel 8, thus forming an independent space inside the valve body 1, isolated from the central cavity of the valve body 1, for carrying the leaking medium. The leak collecting chamber 7 is connected to the detection interface 17 on the outer wall of the valve body 1. The detection interface 17 can be connected to a pressure sensor, a fluid sensor, or other leak monitoring module. Real-time acquisition of pressure or medium state changes within the leak collecting chamber 7 indirectly reflects changes in the sealing performance of the main sealing area.

[0027] This embodiment provides a flat plate valve with leakage detection function. By introducing a leakage collection area into the valve seat 3 structure, and in conjunction with an annular collection groove 5, microchannels, and an independent leakage collection chamber 7, the leakage medium is confined to a preset collection path, preventing it from directly entering the valve body 1 cavity or spreading along the pipeline, thus improving the sensitivity and reliability of leakage detection. The leakage monitoring module can work continuously while the valve is in online operation, enabling real-time online monitoring of sealing performance without disassembling the valve. This facilitates long-term monitoring and preventive maintenance of the valve's operating status, and is suitable for pipelines carrying high-risk media such as oil and gas and chemicals, improving system safety and intelligent operation and maintenance levels.

[0028] Example 2: Based on Example 1 above, the flat plate valve with leakage detection function further includes an elastic element 10. The elastic element 10 is disposed between the valve seat 3 and the valve body 1 and is located on the side away from the valve plate 2. It is used to apply a pre-tightening force in the direction of the valve plate 2 to maintain the valve seat 3 and the valve plate 2 in a fitted state.

[0029] The working principle and beneficial effects of the above technical solution are as follows: When the valve is closed, the elastic element 10 transmits the elastic preload to the valve plate 2 through the valve seat 3, ensuring that the main sealing area remains in close contact with the valve plate 2. When the valve plate 2 experiences slight axial displacement during opening and closing, the elastic element 10 can compensate for this displacement through its own elastic deformation, preventing the valve seat 3 from detaching or warping due to rigid constraints.

[0030] During the leakage detection process, even if the valve is in a state of long-term operation or frequent opening and closing, the elastic element 10 can still continuously apply a stable force to the valve seat, so that the change in the sealing state of the main sealing area mainly comes from the actual sealing wear or internal leakage, rather than structural loosening or changes in assembly gaps, which is conducive to the leakage medium entering the annular collection groove 5 according to the predetermined path.

[0031] In this embodiment, by providing an elastic element between the valve seat 3 and the valve body 1, the adaptive maintenance of the contact state between the valve seat 3 and the valve plate 2 is achieved. This enables the leakage detection structure to obtain a more stable and continuous monitoring signal, avoiding misjudgments or detection drift caused by fluctuations in the contact state. The elastic element 10 enhances the structural stability of the valve during long-term operation, allowing for continuous and reliable online monitoring of the valve without disassembly.

[0032] Example 3: Based on Example 1 above, an isolation lip 6 is provided at the opening of the annular collecting groove 5. The isolation lip 6 is used to prevent the medium from directly entering the annular collecting groove 5 under normal sealing conditions, and to guide the leaking medium across the isolation lip 6 into the annular collecting groove 5 when internal leakage occurs.

[0033] The working principle and beneficial effects of the above technical solution are as follows: When the valve is closed normally and there is no internal leakage in the main sealing area, the medium pressure mainly acts on the main sealing area. The isolation lip 6 is located outside the main sealing area. Under pressure, the medium is difficult to cross the isolation lip 6 and enter the annular collection groove, thus keeping the leakage collection area in a relatively "static" state and preventing irrelevant media from entering the detection link.

[0034] When internal leakage occurs in the main sealing area due to wear, localized damage, or impurity inclusion, the leaking medium moves outward along the interface between the valve plate 2 and the valve seat 3. When a gap appears between the main sealing area and the valve plate 2, the isolation lip 6 cannot maintain a tight seal with the valve plate 2, and may even separate. Driven by the pressure difference, the leaking medium gradually crosses the isolation lip 6 and is guided into the annular collecting groove 5. At this time, the isolation lip 6 changes from a blocking structure to a guiding structure, concentrating the leaking medium between the inner and outer isolation lips 6, allowing the leaking medium to enter the leakage collecting path in a predetermined direction.

[0035] This embodiment, by providing an isolation lip 6 at the opening of the annular collecting groove 5, can block the medium when the main sealing area is in a normal sealing state, preventing the medium from entering the collecting structure and interfering with the detection signal, and effectively distinguishing between the normal sealing state and the actual internal leakage state. This structure significantly reduces the risk of false alarms caused by pressure fluctuations, medium disturbances, or condensate accumulation, and improves the reliability of leakage detection results.

[0036] Example 4: Based on Example 1 above, the annular collecting groove 5 is arranged in a continuous annular shape along the circumference of the valve seat 3, and the cross-section is set as V-shaped; the first microchannel 8 is set as multiple and evenly arranged along the circumference of the valve seat 3, which is used to guide the medium in the annular collecting groove 5 to the leakage collecting cavity 7.

[0037] The working principle and beneficial effects of the above technical solution are as follows: The cross-section of the annular collecting tank 5 is set to V-shape. After the leaking medium enters, it can guide the medium along the inclined tank wall to the bottom of the tank under pressure, reducing the lateral diffusion or retention of the medium in the tank.

[0038] Multiple first microchannels 8 are arranged circumferentially in the annular collecting groove 5. When internal leakage occurs at any position of the valve plate 2, the leaking medium enters the annular collecting groove 5, diffuses circumferentially, and enters the leakage collecting cavity 7 at the nearest first microchannel 8. The arrangement of multiple first microchannels 8 avoids the leakage signal from relying too much on a single channel, improves the system's response speed to random circumferential leakage, and is conducive to long-term online monitoring.

[0039] Example 5: Based on Example 1 above, two sealing rings 9 are provided on both sides of the leakage collection cavity 7. The sealing rings 9 are installed between the outer wall of the valve seat 3 and the valve body 1, and the distance between the two sealing rings 9 is greater than the inlet width of the leakage collection cavity 7, so as to block the direct communication between the middle cavity of the valve body 1 and the leakage collection cavity 7.

[0040] The working principle and beneficial effects of the above technical solution are as follows: In this embodiment, two sealing rings 9 are provided on both sides of the leakage collection cavity 7. In the assembled state, the two sealing rings 9 form a double radial sealing barrier between the valve body 1 and the valve seat 3, so that the leakage collection cavity 7 is isolated from the valve body cavity in both the axial and radial directions. The leakage medium can only enter the leakage collection cavity 7 through the first microchannel 8, and cannot connect with the main channel through other paths, thereby ensuring that the signal collected by the detection interface has higher authenticity and stability.

[0041] In addition, since the valve seat 3 can undergo slight axial displacement, the distance between the two sealing rings 9 is set to be greater than the inlet width of the leakage collection chamber 7, so as to ensure that the leakage collection chamber 7 can completely collect the leakage medium during the displacement process.

[0042] This embodiment significantly improves the anti-interference capability of the leakage detection system through the double sealing ring structure, making the leakage collection chamber 7 a relatively independent and controllable detection space. This effectively avoids the problem of incomplete collection of leakage medium caused by the valve seat 3 shifting due to jetting or impact caused by the pressure of the main fluid, thus improving the detection accuracy.

[0043] Example 6: Based on Example 1 above, a leakage drainage assembly is provided at the bottom of the annular collection tank 5. The leakage drainage assembly includes the following components: Drainage cavity 11 is disposed on valve seat 3 and communicates with annular collection groove 5 and first microchannel 8; Rotating plate 12 is rotatably disposed in drainage cavity 11. Rotating plate 12 is configured as a fan-shaped plate, and its rotation center is located at the center of the fan-shaped plate. A coil spring is provided at the connection between rotating plate 12 and drainage cavity 11. The coil spring is used to make rotating plate 12 always have a tendency to rotate in the direction of annular collection groove 5. The drainage channel 13 is set on the rotating plate 12 and is used to intermittently connect the annular collection groove 5 and the first microchannel 8 during the rotation of the rotating plate 12.

[0044] The working principle and beneficial effects of the above technical solution are as follows: When the leakage fluctuates or increases instantaneously, if the leaking medium continuously and in large quantities enters the detection channel, it may cause overshoot in the detection signal or even damage the detection interface. Therefore, a structure capable of intermittently diverting and slowly releasing the leaking medium is needed.

[0045] In this embodiment, a leakage drainage component is provided at the bottom of the annular collection tank 5. The rotating plate 12 forms an elastic reset relationship with the drainage cavity 11 through a coil spring, so that the rotating plate 12 maintains its initial angle position in a state of no leakage or low leakage.

[0046] When the leaking medium enters the drainage chamber 11 along the annular collecting groove 5, its pressure first acts on the flow-facing surface of the rotating plate 12. As the leakage increases, the rotating plate 12 is pushed to overcome the spring force and deflect at an angle, causing the drainage channel 13 to gradually connect with the first microchannel 8. The leaking medium then enters the subsequent leak collecting chamber 7 along the drainage channel 13 and the first microchannel 8. When the leaking medium is released, the pressure in the drainage chamber 11 decreases, and the spring drives the rotating plate 12 to rotate back to its initial position, disconnecting the drainage channel 13 from the first microchannel 8.

[0047] In this embodiment, the cooperation between the rotating plate 12 and the coil spring enables the self-regulating drainage of the leaking medium, which significantly improves the adaptability of the detection system to leakage fluctuations, effectively prevents the detection system from experiencing sensitive imbalances under conditions of instantaneous large flow and long-term low flow, and improves the stability of long-term monitoring.

[0048] Example 7: Based on Example 1 above, the leakage drainage assembly further includes the following components: Pressure relief channel 14 is provided on the rotating plate 12. Its inlet end is connected to the drainage channel 13, and its outlet end passes through the arc-shaped outer wall of the rotating plate 12. The inner wall of the drainage cavity 11 is in intermittent contact with the outlet end of the pressure relief channel 14. The second microchannel 15 is connected to the side of the drainage cavity 11, and its outlet end is unidirectionally connected to the cavity of the valve body 1. The third microchannel 16 is connected to the side of the drainage cavity 11, and a pressure sensor is connected to its outlet end; the drainage cavity 11 is provided with interfaces corresponding to the first microchannel 8, the second microchannel 15 and the third microchannel 16 in sequence along the depressurization rotation direction of the rotating plate 12.

[0049] The working principle and beneficial effects of the above technical solution are as follows: In a leak detection structure, the leak process is continuous, but when a leak occurs suddenly, the pressure of the leaking medium is too high. The detection interface 17 often directly bears the pressure impact of the leaking medium, resulting in large fluctuations in the detection data, poor repeatability, and even fatigue failure of the detection element.

[0050] When the rotating plate 12 rotates under the action of the leaking medium, there are three working states depending on the different initial leakage pressures of the leaking medium.

[0051] When the medium pressure is less than the first preset pressure value, the rotating plate 12 rotates, the first microchannel 8 connects with the drainage channel 13, and the pressure relief channel 14 is blocked by the inner wall of the drainage cavity 11, forming a stable leakage drainage path.

[0052] When the medium pressure is greater than the first preset pressure value but less than the second preset pressure value, the initial pressure of the leaking medium is relatively high. At this time, the rotation angle of the rotating plate 12 increases, connecting the pressure relief channel 14 with the second microchannel 15, guiding part of the leaking medium back into the cavity of the valve body 1, reducing the direct impact on the detection element, and balancing the pressure in the leakage drainage path. After the initial pressure is released and the leakage drainage reaches a balanced state, it rotates in the opposite direction under the action of the coil spring to reset, re-sealing the pressure relief channel 14. At this time, the initial impact energy of the leaking medium has been released, and the signal collected by the sensor mainly reflects the leakage behavior itself, rather than the instantaneous pressure impact.

[0053] When the medium pressure exceeds the second preset pressure value, the initial pressure of the leaking medium is too high. At this time, the rotating plate 12 rotates significantly, connecting the pressure relief channel 14 with the third microchannel 16, while the drainage channel 13 is blocked by the inner wall of the drainage chamber 11. The pressure sensor at the end of the third microchannel 16 detects the inflow of high-pressure leaking medium and feeds back the detection signal to the control module, indicating that the leakage amount and leakage pressure exceed the safety value, triggering a leakage warning and valve closure operation.

[0054] This embodiment, through a multi-microchannel design, achieves hierarchical management of the leaking medium under different leakage pressure conditions, ensuring that the detection interface 17 always operates in a relatively stable pressure environment. This effectively avoids the leaking medium directly impacting the detection interface 17, significantly improving the stability and repeatability of the detection data, reducing reliance on high-pressure, high-cost sensors, and simultaneously enabling early warning and protection against ultra-high pressure leaks.

[0055] Example 8: Based on Example 1 above, the leak monitoring module and the broadband ultrasonic transducer array connected to the detection interface 17 together constitute a fluid acoustic impedance spectroscopy scanning system. The fluid acoustic impedance spectroscopy scanning system is configured as follows: The broadband ultrasonic transducer array is controlled to transmit a linear frequency-modulated scanning acoustic signal with continuously varying frequency into the acoustically closed cavity formed by the leakage collection cavity 7 and the annular collection groove 5. An initial steady-state acoustic model is established using the reverberation signal generated by the reflection of the linear frequency modulated scanning acoustic signal between the metal cavity wall and the fluid interface of valve body 1. The frequency response function of the acoustic closed cavity to the linear frequency-modulated scanning sound wave signal is acquired in real time, and the first resonant frequency point and the quality factor parameter corresponding to the width of the resonant peak are extracted from the frequency response function using the fast Fourier transform algorithm. The viscous damping coefficient of the fluid medium on the inner wall of the acoustic closed cavity is calculated based on the acoustic boundary layer theory. When the first resonant frequency is detected to shift towards lower frequencies and the quality factor parameter shows an exponential decay, it is determined that there is a high-viscosity liquid medium accumulating at the bottom of the acoustic closed cavity. When the first derivative of the resonance frequency and the second derivative of the quality factor parameter simultaneously satisfy the preset liquid loading characteristic matrix, a real internal leak is confirmed in the main sealing area and a leak alarm signal is triggered.

[0056] The working principle and beneficial effects of the above technical solution are as follows: In traditional petrochemical pipelines, flat valves are frequently affected by multiphase flow, rapid temperature changes, and the reciprocating motion of compressors. Existing technologies, whether relying solely on pressure sensors for monitoring or passively receiving acoustic emission signals, have inherent flaws: pressure sensors cannot distinguish between gas expansion due to temperature increases and liquid accumulation due to actual leaks; passive acoustic emission sensors have extremely low signal-to-noise ratios in high-noise industrial environments and are easily overwhelmed.

[0057] This embodiment employs an active acoustic detection mechanism. The space comprised of the valve body 1, the first microchannel 8, the leakage collection cavity 7, and the annular collection groove 5 is considered a precise acoustic resonant cavity. According to the principles of physical acoustics, any closed cavity has its inherent resonant frequency, which is only related to the cavity geometry and the sound velocity and density of the internal medium. When the cavity is dry, its acoustic impedance spectrum exhibits a high Q-value resonance peak. When a small amount of liquid leaks, the liquid covers the bottom of the annular collection groove 5. Due to the high viscosity and high density of the liquid, it significantly alters the boundary conditions when sound waves are reflected from the cavity walls, producing two significant physical effects: the mass loading effect causes the resonant frequency to drift to lower frequencies; the viscous damping effect causes the sound wave energy to be rapidly dissipated, the resonance peak to broaden, and the Q-value to drop sharply.

[0058] The leak monitoring module integrates a direct digital frequency synthesizer, which periodically transmits linear frequency modulated (LFM) acoustic signals from 20kHz to 100kHz to a broadband ultrasonic transducer installed at detection interface 17. The transducer converts the electrical signals into mechanical vibrations, and the sound waves reciprocate within the cavity. The system simultaneously acquires the echo signals and processes them to obtain the current acoustic impedance spectrum.

[0059] The initial steady-state acoustic model is established as follows: With the valve installed and leak-free, the system first performs a complete frequency scan, recording the frequency response function H0(f) as a reference. This function can be described by the Helmholtz equation: ; Where p is the sound pressure, and k = 2πf / c s f is the frequency of the actively transmitted linear frequency modulated scanning acoustic signal, and c s Let f be the speed of sound in the medium. Solving this equation using finite element analysis yields the theoretical resonant frequency f of the cavity. n0 The corresponding quality factor Q0 is obtained and calibrated with the measured value to establish an initial acoustic model.

[0060] The liquid loading feature matrix M is defined as follows: ; in, For the first First resonant frequency offset This corresponds to the change in the quality factor. This is a preset threshold. When the monitored parameters satisfy the above inequality, the system determines that a true internal leak has occurred.

[0061] Viscous damping coefficient The calculation formula is: ; in, The logarithmic decay rate, For fluid dynamic viscosity, For fluid density, Let be the density of the valve body material. This formula, based on acoustic boundary layer theory, is used to quantify the damping effect of the liquid medium on the inner wall of an acoustically closed cavity.

[0062] The algorithm logic not only focuses on the pressure value but also on the "shift of spectral lines." For example, if the pressure increases by 0.1 MPa but the position of the acoustic resonance peak does not shift and the Q value remains unchanged, the system determines it to be a false pressure caused by gas thermal expansion and does not issue an alarm. Only when the pressure increase is accompanied by a significant frequency shift and broadening of the resonance peak does the system confirm the intrusion of liquid medium, greatly reducing the probability of false alarms.

[0063] Example 9: Based on Example 2 above, a high-frequency response piezoelectric stack actuator is coupled in series between the elastic element 10 and the valve seat 3. The piezoelectric stack actuator is configured to apply micro-amplitude vibration to the valve seat 3 under the control of the leakage monitoring module. The leakage monitoring module is configured to execute a dynamic sealing control strategy based on micro-vibration signal injection. The dynamic sealing control strategy includes: By establishing a second-order dynamic equation that includes the mass of valve seat 3, sealing contact stiffness, and Coulomb friction of the guide surface, the static friction threshold of valve seat 3 during axial feeding is estimated in real time. A set of high-frequency sinusoidal disturbance signals with a frequency higher than the natural frequency of the mechanical system and an amplitude that can cause micron-level deformation is superimposed on the driving voltage of the piezoelectric stacked actuator. The inverse piezoelectric effect is used to induce micro-amplitude vibration in the ultrasonic frequency band between the guide surface of valve seat 3 and valve body 1, so that the friction state of the contact interface is changed from macroscopic static friction to equivalent dynamic friction. While maintaining high-frequency micro-amplitude vibration, the DC bias component in the drive voltage is adaptively adjusted according to the real-time leakage amount, driving the valve seat 3 to generate an axial displacement without overshoot towards the valve plate 2 until the leakage characteristic signal detected by the leakage monitoring module disappears.

[0064] The working principle and beneficial effects of the above technical solution are as follows: In Example 2, although it is mentioned that the elastic element 10 provides preload, under high pressure differential conditions, the passive elastic force alone is insufficient to resist the thrust of the medium, leading to separation of the sealing surface. Therefore, an active actuator (such as a piezoelectric ceramic) is introduced for compensation. However, piezoelectric ceramic compensation encounters the classic problem of static friction creep in mechanical engineering. When the valve seat 3 is fed at the micron level, the static friction is much greater than the dynamic friction. Initially, the valve seat 3 remains stationary when the thrust is applied; once the thrust exceeds the static friction limit, the valve seat 3 will momentarily surge forward excessively, causing the sealing surface to crush or the control system to oscillate.

[0065] The second-order dynamic equation of valve seat 3 is expressed as: ; in, For the mass of valve seat 3, The mechanical damping coefficient is... For sealing contact stiffness, For displacement, External forces (mainly medium pressure) are acting on the surface. The driving force generated by the piezoelectric stack, Friction model: ; in, This represents the amplitude of static friction. Let be the amplitude of the Coulomb friction force. For Stribeck speed, The critical speed is defined as . By solving the above equations in real time, the system can accurately estimate the static friction threshold during the axial feed process of valve seat 3.

[0066] The piezoelectric stack actuator is designed with the following parameters: nominal voltage range 0-150V, resolution 0.1V, corresponding displacement resolution 10nm, and maximum stroke 100μm. Driving frequency... Set to 500Hz-1kHz, amplitude This corresponds to a displacement of 0.5-1 μm. This frequency range was determined experimentally, and the first to third natural frequencies of the valve body 1 structure must be avoided. Specifically, it can be obtained by measuring the frequency response function (FRF) of the valve body 1 using the hammer impact method.

[0067] The adaptive control algorithm employs an improved PID controller with a DC bias component. The calculation formula is: ; in, This is a leakage error signal. , , The PID control parameters are tuned using the Ziegler-Nichols method. To compensate for the voltage term and counteract the offset caused by the medium pressure, the system sets the maximum displacement rate limit to 0.1 μm / ms to avoid overshoot, and uses an S-shaped velocity curve to plan the motion trajectory of valve seat 3.

[0068] In this embodiment, a ring-shaped high-voltage piezoelectric stack is installed in series between the elastic element 10 and the valve seat 3. This stack is pre-tightened and encapsulated, with a nominal stroke of 100 μm and a resolution of 10 nm. The driver employs an AC / DC superimposed amplifier circuit constructed from high-voltage operational amplifiers.

[0069] The control algorithm is based on conventional PID control voltage. A high-frequency AC signal is superimposed on top of it. ; The frequency range is set to 500Hz-1kHz, and the low-order natural frequencies of the valve body structure should be avoided to prevent resonance. This corresponds to a piezoelectric displacement of 0.5-1 μm.

[0070] This embodiment utilizes the inverse piezoelectric effect, where a piezoelectric stack drives the valve seat 3 to generate high-frequency micro-amplitude vibrations relative to the guide surface of the valve body 1. From a tribological perspective, this micro-vibration keeps the contact surface in a "quasi-dynamic" state, disrupting the engagement of the contact micro-protrusions and thus eliminating the macroscopic static friction threshold. At this point, the relationship between friction and velocity is linearized. Due to the elimination of static friction hysteresis, the axial displacement of the valve seat 3 can linearly and smoothly follow the DC control voltage. The system can push the valve seat 3 towards the valve plate 2 with nanometer-level stepping precision, stopping the feed at the exact moment the leakage channel is cut off. This achieves sealing while avoiding excessive contact stress that could damage the sealing surface. Compared to stepper motors or hydraulic cylinders, this piezoelectric control based on micro-vibration offers high precision and is particularly suitable for micro-leakage control of valves handling high-pressure and high-risk media.

[0071] Example 10: The rotating plate 12 includes several fluid cutting grids that are non-uniformly distributed along the circumference, causing pressure pulsation signals to be generated when the rotating plate 12 rotates under the drive of the leaking medium; the leakage monitoring module is configured to execute mechanical fault self-diagnosis logic based on the pressure pulsation signals: When the leaking medium flows through the rotating, non-uniformly distributed fluid cutting grid, it generates a periodic on-off cutting action on the fluid entering the leak collection chamber 7 through the first microchannel 8, thereby superimposing a pressure pulsation signal with specific time-domain coding characteristics onto the fluid static pressure signal at the detection interface 17. The leakage monitoring module processes the collected pressure pulsation signal and demodulates the carrier frequency signal containing the real-time angular velocity information of the rotating plate 12 and the duty cycle signal reflecting the flow channel on / off ratio. The demodulated carrier frequency signal is cross-correlated with the theoretical rotational speed calculated based on the fluid dynamics model. If the fluid static pressure is detected to be rising continuously but the corresponding carrier frequency component is missing in the pressure pulsation signal, or if the rate of change of the carrier frequency and the rate of increase of the fluid pressure do not conform to the linear relationship defined by Hooke's law of coiled springs, it is determined that mechanical jamming or failure of the elastic reset element has occurred inside the leakage drainage component.

[0072] The working principle and beneficial effects of the above technical solution are as follows: In the aforementioned mechanical drainage scheme, the rotating plate 12 and the coil spring are enclosed inside the high-temperature and high-pressure drainage chamber 11. If impurities cause the rotating plate 12 to jam, or if metal fatigue causes the coil spring to break, the external sensor will not be able to detect it. However, if a position sensor is installed by drilling a hole in the valve body 1, the pressure-bearing integrity will be compromised, adding a new leakage point.

[0073] The fluid cutting grid on the rotating plate 12 adopts a specific non-uniform distribution design. The specific parameters are as follows: the circumference of the rotating plate 12 is divided into 8 equal regions, and the grid opening widths are distributed according to the central angle sequence [30°, 15°, 45°, 10°, 35°, 20°, 40°, 5°]. The spacing between adjacent grids is 10°. This distribution pattern, optimized through fluid dynamics simulation, can generate a time-domain encoded signal with unique identification characteristics, effectively resisting fluid noise interference.

[0074] When a leak occurs, the fluid pushes the rotating plate 12 to rotate. As the fluid flows through the rotating grid, it is periodically interrupted, resulting in pulsating flow rates. Because the grid is non-uniform, the generated pulsating pressure waveform carries specific time-domain encoded characteristics. This is equivalent to modulating mechanical motion information into the fluid pressure signal. The pressure sensor at detection interface 17 acquires pressure data at a high sampling rate of 2kHz. The leak monitoring module performs the following demodulation steps: Step 1: Raw pressure signal First, a high-pass filter with a cutoff frequency of 0.1Hz is used to remove the DC component, and then a low-pass filter with a cutoff frequency of 100Hz is used to filter out high-frequency noise, resulting in the processed signal. .

[0075] Step 2, for Perform Empirical Mode Decomposition (EMD) to decompose the signal into... One intrinsic mode function (IMF): ; in, For the first One IMF, The term is a residual. The IMF with the highest energy concentration is selected as the carrier signal. Perform a Hilbert transform on it: ; Calculate the instantaneous frequency and amplitude of the analytic signal: ; ; Finally, state inversion is performed. If the demodulated waveform envelope exhibits a periodic change consistent with the wide, narrow, wide, narrow grid design, and the carrier frequency has a square root relationship with the average static pressure (consistent with the fluid drive equation), then the leakage drainage component is determined to be in a healthy state. When the rate of continuous increase in hydrostatic pressure exceeds the threshold, However, the standard deviation of instantaneous frequency If the duration exceeds 2 seconds, the system determines that the turntable 12 is mechanically stuck; When the coil spring is working normally, according to Hooke's Law, the angular velocity of the rotating plate 12 is... With fluid pressure Satisfy linear relationship ,in This is the spring stiffness coefficient, with a theoretical value of 0.25 rad / (s·MPa). When detected... If the duration exceeds 1 second, the system determines that the coil spring has failed.

[0076] This invention, without adding any internal electronic components or damaging the structure of valve body 1, can not only determine whether there is a leak by deeply decoding the fluid waveform, but also accurately calculate the rotation speed and position of the internal rotating plate and the health status of the reset mechanism through demodulation signals, thus realizing visualized monitoring of the health status of the internal closed mechanical moving parts.

[0077] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0078] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0079] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A flat plate valve with leakage detection function, comprising a valve body (1), a valve plate (2) disposed within the valve body (1), valve seats (3) fitted to both sides of the valve plate (2), and a valve stem (4) for driving the valve plate (2) to move, characterized in that, The valve seat (3) includes an inner leakage collection area and an outer main sealing area. The main sealing area is used to form a main seal with the valve plate (2). The leakage collection area includes an annular collection groove (5) arranged around the valve seat (3). An annular leakage collection cavity (7) is provided on the valve body (1). The leakage collection cavity (7) is connected to the annular collection groove (5) through a first microchannel (8). A detection interface (17) is provided on the outer wall of the valve body (1) and is connected to the leakage collection cavity (7). The detection interface (17) is connected to a leakage monitoring module for detecting the leakage status of the medium entering the leakage collection cavity (7). The bottom of the annular collection tank (5) is equipped with a leakage drainage assembly, which includes the following components: Drainage cavity (11) is provided on valve seat (3) and communicates with annular collection groove (5) and first microchannel (8); Rotating plate (12) is rotatably disposed in drainage cavity (11). Rotating plate (12) is configured as a fan-shaped plate, and its rotation center is located at the center of the fan-shaped plate. A coil spring is provided at the connection between rotating plate (12) and drainage cavity (11). The coil spring is used to make rotating plate (12) always have the tendency to rotate in the direction of annular collection groove (5). The drainage channel (13) is set on the rotating plate (12) to allow the annular collection groove (5) to be intermittently connected with the first microchannel (8) during the rotation of the rotating plate (12); Pressure relief channel (14) is set on the rotating plate (12). Its inlet end is connected to the drainage channel (13), and its outlet end passes through the arc-shaped outer wall of the rotating plate (12). The inner wall of the drainage cavity (11) is in intermittent contact with the outlet end of the pressure relief channel (14). The second microchannel (15) is connected to the side of the drainage cavity (11), and its outlet end is unidirectionally connected to the cavity of the valve body (1). The third microchannel (16) is connected to the side of the drainage cavity (11), and a pressure sensor is connected to the outlet end; the drainage cavity (11) is provided with interfaces corresponding to the first microchannel (8), the second microchannel (15) and the third microchannel (16) in sequence along the depressurization rotation direction of the rotating plate (12).

2. A flat plate valve with leakage detection function according to claim 1, characterized in that, It also includes an elastic element (10), which is disposed between the valve seat (3) and the valve body (1) and located on the side away from the valve plate (2), and is used to apply a pre-tightening force in the direction of the valve plate (2) to maintain the fit between the valve seat (3) and the valve plate (2).

3. A flat plate valve with leakage detection function according to claim 1, characterized in that, An isolation lip (6) is provided at the opening of the annular collecting groove (5). The isolation lip (6) is used to prevent the medium from directly entering the annular collecting groove (5) under normal sealing conditions, and to guide the leaking medium across the isolation lip (6) into the annular collecting groove (5) when internal leakage occurs.

4. A flat plate valve with leakage detection function according to claim 1, characterized in that, The annular collecting groove (5) is arranged in a continuous annular shape along the circumference of the valve seat (3), and the cross-section is set as V-shaped; the first microchannel (8) is set as multiple and evenly arranged along the circumference of the valve seat (3) to guide the medium in the annular collecting groove (5) to the leakage collecting cavity (7).

5. A flat plate valve with leakage detection function according to claim 1, characterized in that, Two sealing rings (9) are provided on both sides of the leakage collection cavity (7). The sealing rings (9) are installed between the outer wall of the valve seat (3) and the valve body (1), and the distance between the two sealing rings (9) is greater than the inlet width of the leakage collection cavity (7) to block the direct connection between the middle cavity of the valve body (1) and the leakage collection cavity (7).

6. A flat plate valve with leakage detection function according to claim 1, characterized in that, The leakage monitoring module and the broadband ultrasonic transducer array connected to the detection interface (17) together constitute a fluid acoustic impedance spectroscopy scanning system, which is configured as follows: The broadband ultrasonic transducer array is controlled to emit a linear frequency-modulated scanning acoustic signal with continuously changing frequency into the acoustic closed cavity formed by the leakage collection cavity (7) and the annular collection groove (5); An initial steady-state acoustic model is established by using the reverberation signal formed by the reflection of the linear frequency modulated scanning acoustic signal between the metal cavity wall and the fluid interface of the valve body (1); The frequency response function of the acoustic closed cavity to the linear frequency-modulated scanning sound wave signal is acquired in real time, and the first resonant frequency point and the quality factor parameter corresponding to the width of the resonant peak are extracted from the frequency response function using the fast Fourier transform algorithm. The viscous damping coefficient of the fluid medium on the inner wall of the acoustic closed cavity is calculated based on the acoustic boundary layer theory. When the first resonant frequency is detected to shift towards lower frequencies and the quality factor parameter shows an exponential decay, it is determined that there is a high-viscosity liquid medium accumulating at the bottom of the acoustic closed cavity. When the first derivative of the resonance frequency and the second derivative of the quality factor parameter simultaneously satisfy the preset liquid loading characteristic matrix, a real internal leak is confirmed in the main sealing area and a leak alarm signal is triggered.

7. A flat plate valve with leakage detection function according to claim 2, characterized in that, A high-frequency piezoelectric stack actuator is coupled in series between the elastic element (10) and the valve seat (3). The piezoelectric stack actuator is configured to apply micro-amplitude vibration to the valve seat (3) under the control of the leakage monitoring module. The leakage monitoring module is configured to execute a dynamic sealing control strategy based on micro-vibration signal injection. The dynamic sealing control strategy includes: By establishing a second-order dynamic equation that includes the mass of the valve seat (3), the sealing contact stiffness, and the Coulomb friction of the guide surface, the static friction threshold of the valve seat (3) during the axial feeding process is estimated in real time. A set of high-frequency sinusoidal disturbance signals with a frequency higher than the inherent frequency of the mechanical system and an amplitude that can cause micron-level deformation is superimposed on the driving voltage of the piezoelectric stack actuator. The inverse piezoelectric effect is used to induce micro-amplitude vibration in the ultrasonic frequency band between the guide surface of the valve seat (3) and the valve body (1), so that the friction state of the contact interface changes from macroscopic static friction to equivalent dynamic friction. While maintaining high-frequency micro-amplitude vibration, the DC bias component in the drive voltage is adaptively adjusted according to the real-time leakage amount, driving the valve seat (3) to generate an axial displacement without overshoot towards the valve plate (2) until the leakage characteristic signal detected by the leakage monitoring module disappears.

8. A flat plate valve with leakage detection function according to claim 1, characterized in that, The rotating plate (12) contains several fluid cutting grids that are non-uniformly distributed along the circumference, causing the rotating plate (12) to generate pressure pulsation signals when it rotates under the drive of the leaking medium; the leakage monitoring module is configured to execute mechanical fault self-diagnosis logic based on the pressure pulsation signals: When the leaking medium flows through the rotating, non-uniformly distributed fluid cutting grid, it generates a periodic on-off cutting action on the fluid entering the leak collection chamber (7) through the first microchannel (8), thereby superimposing a pressure pulsation signal with specific time-domain coding characteristics on the fluid static pressure signal at the detection interface (17). The leakage monitoring module processes the collected pressure pulsation signal and demodulates the carrier frequency signal containing the real-time angular velocity information of the rotating plate (12) and the duty cycle signal reflecting the flow channel on / off ratio. The demodulated carrier frequency signal is cross-correlated with the theoretical rotational speed calculated based on the fluid dynamics model. If the fluid static pressure is detected to be rising continuously but the corresponding carrier frequency component is missing in the pressure pulsation signal, or if the rate of change of the carrier frequency and the rate of increase of the fluid pressure do not conform to the linear relationship defined by Hooke's law of coiled springs, it is determined that mechanical jamming or failure of the elastic reset element has occurred inside the leakage drainage component.

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