High-temperature butterfly valve hard sealing test evaluation method and system

Abstract

The application relates to the technical field of sealing detection, and discloses a high-temperature butterfly valve hard sealing test evaluation method and system, which comprises the following steps: collecting thermal state closing reference data of a measured high-temperature butterfly valve, and processing the thermal state closing reference data. The valve position angle, closing torque and leakage amount in the thermal state closing process are collected, and a sealing critical angle area is determined. A thermal state micro-swing test is carried out, and a disturbance leakage increment and an abnormal torque angle section are obtained. When the disturbance leakage increment exceeds a leakage increment threshold value, the valve plate is returned to an opening side position outside the sealing critical angle area, and high-temperature medium is introduced to perform thermal equalization review. The measured high-temperature butterfly valve is closed again, the review leakage amount and the review torque are collected, the leakage type result is generated according to the review leakage amount and the review torque, and the life evaluation result is generated. The application can distinguish between recoverable thermal deformation abnormalities and unrecoverable hard sealing damage, and the accuracy of high-temperature butterfly valve hard sealing life evaluation is improved.

Description

Technical Field

[0001] This invention relates to the field of sealing testing technology, and more specifically, to a method and system for evaluating the hard seal of a high-temperature butterfly valve. Background Technology

[0002] High-temperature butterfly valves are typically used for opening, closing, shut-off, and regulation of high-temperature flue gas, high-temperature gases, or high-temperature process media. The hard seal pair must simultaneously withstand temperature cycling, media pressure differentials, opening and closing friction, and localized thermal deformation. Compared to room-temperature soft-seal valves, the hard seal performance of high-temperature butterfly valves depends not only on the single-time leakage rate but also on torque changes during hot closure, valve seat temperature distribution, the contact state between the valve plate and valve seat, and the leakage trend after multiple openings and closings. Therefore, when evaluating the hard seal of a high-temperature butterfly valve, it is necessary to obtain test results under high-temperature conditions that reflect changes in the sealing condition and the trend of lifespan degradation. This provides a basis for hard seal structure design, actuator setting, and subsequent health management.

[0003] In existing technologies, such as Chinese invention patent application CN118857717A - Valve High Temperature Testing Machine, a valve high temperature testing machine is disclosed. This machine uses a gas storage tank, gas heater, connecting pipes of different specifications, a valve testing station, temperature control sensors, and pressure sensors to perform high-temperature tests on different types of valves. It primarily addresses the problems of traditional valve high temperature testing machines, which typically can only test valves of matching models and have low testing efficiency. It can also perform valve life and sealing performance tests. While this technology can provide a high-temperature testing environment and basic leakage detection conditions, for high-temperature butterfly valve hard seal tests, leakage changes during the test may be affected by factors such as thermal deformation, changes in the closed state, local contact anomalies, or hard seal surface deterioration. If evaluation is based solely on a single leakage detection under high-temperature conditions or conventional life test results, leakage anomalies caused by different reasons may be grouped into the same evaluation conclusion, thus affecting the accuracy of hard seal life judgment, fault prediction, and health management results.

[0004] Therefore, it is necessary to design a test evaluation method and system for high-temperature butterfly valve hard seals to solve the problems existing in the current technology. Summary of the Invention

[0005] In view of this, the present invention proposes a method and system for evaluating the hard seal test of high-temperature butterfly valves, aiming to solve the problem that the evaluation of high-temperature valves based solely on conventional leakage detection or life test results is difficult to distinguish the source of abnormal leakage in the hard seal of high-temperature butterfly valves, resulting in insufficient accuracy in life assessment and health management results.

[0006] This invention proposes a method for evaluating the hard seal of a high-temperature butterfly valve, comprising: Collect hot-state shut-off baseline data of the tested high-temperature butterfly valve, process the hot-state shut-off baseline data to obtain the hot-state leakage baseline range, hot-state temperature difference baseline range, torque fluctuation threshold and leakage increment threshold; The valve position angle, closing torque, and leakage amount are collected during the hot-state closing process of the tested high-temperature butterfly valve. Based on the continuously rising position of the closing torque and the position where the leakage amount enters the hot-state leakage baseline range, the sealing critical angle zone is determined. A hot micro-oscillation test was conducted in the critical sealing angle region to obtain the disturbance leakage increment and abnormal torque angle range. When the disturbance leakage increment exceeds the leakage increment threshold, the valve plate is moved back to the open side position outside the sealing critical angle region, and a high-temperature medium is introduced for thermal equilibrium verification until the circumferential temperature difference of the valve seat enters the hot temperature difference baseline range. After thermal equilibrium verification, the tested high-temperature butterfly valve is closed again, and the verification leakage amount and verification torque are collected. Based on whether the verification leakage amount enters the hot leakage baseline range and whether the verification torque exceeds the torque fluctuation threshold in the abnormal torque angle range, a leakage type result is generated, and a life evaluation result is generated based on the leakage type result.

[0007] Furthermore, when acquiring hot-state shutdown baseline data to obtain the hot-state leakage baseline range, the hot-state temperature difference baseline range, the torque fluctuation threshold, and the leakage increment threshold, the process includes: After the tested high-temperature butterfly valve reaches the test temperature and stabilizes, the hot-state closing reference data is collected. The hot-state closing reference data includes the reference leakage, the reference valve seat circumferential temperature difference, and the reference closing torque. The hot leakage baseline range and the leakage increment threshold are obtained based on the reference leakage amount, the hot temperature difference baseline range is obtained based on the reference valve seat circumferential temperature difference, and the torque fluctuation threshold is obtained based on the reference closing torque.

[0008] Furthermore, determining the critical sealing angle region includes: The valve position angle, the closing torque, and the leakage amount are continuously collected along the closing direction; The position where the increment of the relatively stable closing torque first continuously exceeds the torque fluctuation threshold is determined as the sealing contact position, the position where the leakage enters the hot leakage baseline range is determined as the sealing clamping position, and the angle range between the sealing contact position and the sealing clamping position is determined as the sealing critical angle region.

[0009] Furthermore, during the hot micro-oscillation test in the critical sealing angle region, the following steps are included: The critical sealing angle region is divided into multiple angle segments. Reciprocating micro-oscillation is performed in each angle segment. The leakage before micro-oscillation, the leakage after micro-oscillation, and the disturbance torque are collected, and the hot micro-oscillation test flow rate is recorded. The difference between the leakage after micro-oscillation and the leakage before micro-oscillation is taken as the disturbance leakage increment. The angle segment in which the disturbance torque exceeds the torque fluctuation threshold is taken as the abnormal torque angle segment.

[0010] Furthermore, the thermal equilibrium verification process includes: When the disturbance leakage increment exceeds the leakage increment threshold, the pressure difference of the tested high-temperature butterfly valve is removed, and the valve plate is retracted to the open side of the sealing contact position, so that the valve plate is released from the compressed state of the valve seat; a high-temperature medium with a flow rate lower than that of the hot micro-oscillation test is passed through the gap between the valve plate and the valve seat until the circumferential temperature difference of the valve seat enters the hot temperature difference baseline range.

[0011] Furthermore, when generating leak type results, the following are included: When the verified leakage amount enters the hot leakage baseline range, and the verified torque does not exceed the torque fluctuation threshold in the abnormal torque angle segment, a thermal deformation misalignment type leakage result is generated; When the verified leakage amount does not fall within the hot leakage baseline range, and the verified torque exceeds the torque fluctuation threshold in the abnormal torque angle segment, a hard seal damage type leakage result is generated; When the verified leakage amount enters the hot leakage baseline range, and the verified torque exceeds the torque fluctuation threshold in the abnormal torque angle segment, a critical angle zone scuff risk result is generated; When the verified leakage amount does not fall within the hot leakage baseline range and the verified torque does not exceed the torque fluctuation threshold in the abnormal torque angle segment, a verification abnormal result is generated.

[0012] Furthermore, when generating the life assessment result based on the leakage type result, it includes: The test cycle that generates the thermal deformation misalignment leakage result is marked as a thermal compensation abnormal cycle and is not considered as a hard seal failure cycle. The test cycle that first generates the collision risk result of the critical corner area is marked as a wear warning cycle; The test cycle that generates the aforementioned review anomaly result is marked as a review anomaly cycle; The test cycle that generates the hard seal damage-type leakage result is marked as an irreversible leakage candidate cycle; Based on the thermal compensation abnormal cycle, the wear warning cycle, the verification abnormal cycle, and the unrecoverable leakage candidate cycle, a life evaluation result is generated.

[0013] Furthermore, confirming the candidate cycle for irreversible leakage includes: performing a hot micro-oscillation test and a thermal equilibrium verification after the candidate cycle for irreversible leakage; if subsequent test cycles generate the hard seal damage type leakage result again, and the abnormal torque angle segment in the subsequent test cycles is the same as the abnormal torque angle segment in the candidate cycle for irreversible leakage, then the candidate cycle for irreversible leakage is determined as the initiation cycle for irreversible leakage, and a hard seal life node is generated based on the initiation cycle for irreversible leakage; if subsequent test cycles generate the hard seal damage type leakage result again, but the abnormal torque angle segment in the subsequent test cycles is different from the abnormal torque angle segment in the candidate cycle for irreversible leakage, then the subsequent test cycles are marked as new candidate cycles for irreversible leakage; if subsequent test cycles do not generate the hard seal damage type leakage result again, then the candidate cycle for irreversible leakage is remarked as a verification abnormal cycle.

[0014] Furthermore, generating the lifespan assessment results includes: A thermal compensation anomaly alert is generated based on the thermal compensation anomaly cycle; a hard seal wear warning node is generated based on the wear warning cycle; and a re-verification alert is generated based on the verification anomaly cycle. When an irreversible leakage initiation cycle exists, a hard seal life node and a hard seal failure determination result are generated based on the irreversible leakage initiation cycle. The generated thermal compensation anomaly alert, hard seal wear warning node, re-verification alert, hard seal life node, and hard seal failure determination result are used as the life evaluation result.

[0015] Compared with existing technologies, the advantages of this invention are as follows: By establishing hot-state leakage baseline range, hot-state temperature difference baseline range, torque fluctuation threshold, and leakage increment threshold using hot-state shutdown reference data, the test judgment has its own hot-state reference for the same test object, reducing evaluation bias caused by differences in valve size, sealing pair processing state, coating state, and test temperature; The sealing critical angle zone is determined based on the position of continuous increase in closing torque and the position where leakage enters the hot-state leakage baseline range, focusing the test on the critical angle range between the valve plate and valve seat from contact to clamping, rather than making a rough evaluation of the entire opening and closing stroke, thus more accurately capturing the sensitive stage where hard seals rub, gnaw, locally wear, or hot-state misalignment occur at the closing end; The disturbance leakage increment and... are obtained through hot-state micro-oscillation tests. In the abnormal torque angle segment, after a leakage anomaly occurs, the hard seal failure is not directly determined. Instead, the valve plate is moved back to the open side position outside the critical angle zone of the seal, and a high-temperature medium is introduced for thermal equalization verification. The circumferential temperature difference of the valve seat is used to determine whether it returns to the baseline range of the hot temperature difference to eliminate false leakage anomalies caused by instantaneous thermal deformation or uneven temperature distribution. After the thermal equalization verification, the tested high-temperature butterfly valve is closed again. The leakage is verified to have recovered, and the torque is verified to have exceeded the torque fluctuation threshold again in the abnormal torque angle segment. The leakage type result and life evaluation result are generated. This distinguishes between recoverable thermal misalignment, critical angle zone contact anomaly, and irreversible hard seal damage, avoiding the simple classification of leakage anomalies caused by different reasons into the same failure conclusion, and improving the accuracy of the hard seal life evaluation of high-temperature butterfly valves.

[0016] On the other hand, this application also provides a high-temperature butterfly valve hard seal test evaluation system for applying the above-mentioned high-temperature butterfly valve hard seal test evaluation method, including: The data acquisition unit is configured to acquire the hot-state closing reference data, hot-state closing process data, hot-state micro-oscillation test data, and thermal equilibrium verification data of the tested high-temperature butterfly valve. The processing unit is configured to process the hot shut-off reference data to obtain the hot leakage baseline range, the hot temperature difference baseline range, the torque fluctuation threshold and the leakage increment threshold, determine the sealing critical angle zone based on the hot shut-off process data, and obtain the disturbance leakage increment and abnormal torque angle segment based on the hot micro-oscillation test data. The verification unit is configured to control the valve plate to retract and allow high-temperature medium to be introduced when the disturbance leakage increment exceeds the leakage increment threshold, so as to perform thermal equalization verification. The evaluation unit is configured to generate a leakage type result based on the verified leakage amount and verified torque, and to generate a life evaluation result based on the leakage type result.

[0017] It is understandable that the above-mentioned high-temperature butterfly valve hard seal test evaluation method and system have the same beneficial effects, and will not be elaborated here. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A flowchart of the high-temperature butterfly valve hard seal test evaluation method provided in the embodiments of the present invention; Figure 2 A flowchart for hot micro-oscillation, thermal equilibrium verification, and leakage type determination in the sealing critical angle region provided in this embodiment of the invention; Figure 3 This is a functional block diagram of the high-temperature butterfly valve hard seal test and evaluation system provided in an embodiment of the present invention. Detailed Implementation

[0019] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] In some embodiments of this application, see Figures 1-2 As shown, this application proposes a test evaluation method for the hard seal of a high-temperature butterfly valve, including: S100: Collects the hot-state closing reference data of the tested high-temperature butterfly valve, processes the hot-state closing reference data, and obtains the hot-state leakage baseline range, hot-state temperature difference baseline range, torque fluctuation threshold, and leakage increment threshold.

[0021] S200: Collects the valve position angle, closing torque, and leakage during the hot-state closing process of the tested high-temperature butterfly valve. Based on the continuous rise of the closing torque and the position where the leakage enters the hot-state leakage baseline range, the critical sealing angle zone is determined.

[0022] S300: Conduct a hot micro-oscillation test in the critical sealing angle region to obtain the disturbance leakage increment and abnormal torque angle range.

[0023] S400: When the disturbance leakage increment exceeds the leakage increment threshold, the valve plate is moved back to the open side position outside the sealing critical angle zone, and a high-temperature medium is introduced for thermal equilibrium verification until the circumferential temperature difference of the valve seat enters the hot temperature difference baseline range.

[0024] S500: After thermal equilibrium verification, the tested high-temperature butterfly valve is closed again, and the verification leakage and verification torque are collected. Based on whether the verification leakage enters the hot leakage baseline range and whether the verification torque exceeds the torque fluctuation threshold in the abnormal torque angle range, leakage type results are generated, and life evaluation results are generated based on the leakage type results.

[0025] Specifically, in this embodiment, the high-temperature butterfly valve under test is installed in a test pipeline capable of providing high-temperature medium, medium pressure difference, valve position control, torque acquisition, leakage measurement, and valve seat circumferential temperature acquisition. Before the test, the fully closed position of the valve plate is defined as the closing endpoint, and the position where the valve plate deflects in the opening direction is defined as the opening side position. The test temperature is determined according to the design operating conditions of the high-temperature butterfly valve under test, such as its rated operating temperature or a specified verification temperature. Thermal stability refers to the temperature changes at multiple temperature measurement positions around the valve seat remaining within the allowable fluctuation range within a preset time after the high-temperature butterfly valve under test reaches the test temperature. This allowable fluctuation range can be determined according to the test temperature control accuracy, for example, taking the larger of the allowable error of the temperature acquisition device and the fluctuation of the high-temperature furnace or high-temperature medium control. After thermal stability is completed, at least three hot-state closing benchmark tests are conducted under the same test temperature, the same closing speed, and the same medium pressure difference. The benchmark leakage, benchmark valve seat circumferential temperature difference, and benchmark closing torque are collected in each test to obtain the hot-state closing benchmark data.

[0026] When processing the hot-state shutdown baseline data, the hot-state leakage baseline range can be determined by the center value of multiple baseline leakage quantities and the repeated sampling fluctuations. The repeated sampling fluctuations can be the difference between the maximum and minimum values ​​among the multiple baseline leakage quantities, or the maximum deviation of the baseline leakage quantity relative to the center value. The leakage increment threshold can be determined based on the repeated sampling fluctuations of the baseline leakage quantity and the minimum resolution of the leakage metering device, preferably the larger of the two, to avoid mistaking leakage metering noise for an actual increase in leakage. The hot-state temperature difference baseline range can be determined based on the fluctuations of the circumferential temperature difference of the valve seat under stable insulation conditions, used to determine whether the thermal equilibrium verification has eliminated circumferential heating unevenness. The torque fluctuation threshold can be determined based on the fluctuations of the baseline shutdown torque in the stable shutdown section, preferably based on the maximum fluctuation of the torque in the stable shutdown section or the resolution of the torque acquisition device, thereby avoiding mistaking occasional sampling spikes for abnormal hard seal contact.

[0027] In one possible implementation, the center value of the reference leakage rate can be taken as the average of multiple reference leakage rates, and the hot leakage baseline range can be taken as the range after repeatedly collecting fluctuations upward and downward from the center value. When the value after downward expansion is less than zero, zero is taken as the lower limit of the hot leakage baseline range. The leakage increment threshold can be taken as the larger of the repeated sampling fluctuations of the reference leakage rate, three times the minimum resolution of the leakage metering device, and the no-load leakage fluctuation of the test pipeline. The reference valve seat circumferential temperature difference can be taken as the difference between the highest and lowest temperatures among multiple circumferential temperature measurement positions, and the hot temperature difference baseline range can be taken as the range after expanding the center value of the reference valve seat circumferential temperature difference upward from the temperature acquisition error and temperature control fluctuations during the heat preservation stabilization stage. The torque fluctuation threshold can be taken as the larger of the maximum fluctuation of the reference closing torque stabilization section, three times the minimum resolution of the torque acquisition device, and 5% of the average value of the reference closing torque stabilization section.

[0028] When determining the critical sealing angle zone, the tested high-temperature butterfly valve is continuously operated from the open state along the closing direction, and the valve position angle, closing torque, and leakage are collected simultaneously. The closing torque is usually relatively stable before the valve plate forms a hard seal with the valve seat. Once the valve plate sealing surface begins to contact the valve seat sealing surface, the closing torque will continuously increase. To avoid misjudgment caused by a single abnormal sampling point, this embodiment defines the position where the increment of the relatively stable closing torque first continuously exceeds the torque fluctuation threshold as the sealing contact position. "Continuously exceeding" can be understood as exceeding the torque fluctuation threshold at multiple consecutive sampling points or within a continuous preset sampling period. If no further settings are made before the test, at least three consecutive sampling points can be taken, and the continuous preset sampling period can be at least three times the valve position sampling cycle. When the sampling point judgment result is inconsistent with the sampling period judgment result, the judgment result with the longer duration and the corresponding synchronous decrease in leakage is taken as the sealing contact position. During the continued closing process, the leakage decreases as the sealing pair gradually tightens. When the leakage enters the hot leakage baseline range, this position is determined as the sealing tightening position. The angular range between the sealing contact position and the sealing compression position is the sealing critical angle zone. This range reflects the actual contact process of the hard seal pair from the start of contact to the achievement of the hot sealing reference, and does not require pre-specified fixed angle boundaries.

[0029] After obtaining the critical sealing angle zone, the critical sealing angle zone is divided into multiple angle segments according to the valve position angle. The width of each angle segment is not less than three times the minimum resolution of the valve position control. When the total angle range of the critical sealing angle zone is small, it should be divided into at least two angle segments to distinguish the initial contact area near the sealing contact position and the pressing area near the sealing pressing position. The same angle segment refers to the position where the verification torque exceeds the torque fluctuation threshold and the position where the disturbance torque exceeds the torque fluctuation threshold falling into the same angle segment. The number of angle segments can be determined according to the total angle range of the critical sealing angle zone and the valve position control accuracy, preferably ensuring that each angle segment can be stably identified by the valve position acquisition device. Subsequently, reciprocating micro-oscillation is performed within each angle segment, with the micro-oscillation amplitude being less than the angle width of that angle segment, or limited by the boundary of adjacent angle segments, so that the valve plate and valve seat repeatedly contact in a state of near-pressurization but not fully stable pressurization. During the hot micro-oscillation test, the leakage before micro-oscillation, the leakage after micro-oscillation, and the disturbance torque are collected, and the hot micro-oscillation test flow rate is recorded. The increase in disturbance leakage is determined by the increase in leakage after micro-oscillation relative to leakage before micro-oscillation. Abnormal torque angle segments are those where the disturbance torque exceeds the torque fluctuation threshold. If multiple angle segments show torque exceeding the torque fluctuation threshold, the angle segment with the largest exceedance and the first occurrence of the exceedance can be recorded as abnormal torque angle segments for subsequent verification to determine if the abnormality recurs at the same contact location.

[0030] When the disturbance leakage increment does not exceed the leakage increment threshold, it indicates that the current hot-state micro-oscillation did not cause a leakage change sufficient to warrant a review, and subsequent test cycles can continue. When the disturbance leakage increment exceeds the leakage increment threshold, it is not directly considered as hard seal damage; instead, a thermal equalization review is performed first. At the start of the thermal equalization review, the pressure differential of the tested high-temperature butterfly valve is first removed to prevent the pressure differential from continuing to act on the sealing pair and amplifying the leakage anomaly. Then, the valve plate is retracted to the open side of the sealing contact position, allowing the valve plate to disengage from the valve seat's compressed state, but still maintaining a position where the high-temperature medium can pass through the gap between the valve plate and the valve seat. Subsequently, a high-temperature medium at a flow rate lower than the hot-state micro-oscillation test flow rate is passed through this gap. The purpose of the low flow rate is to make the circumferential heating of the valve seat more uniform, while avoiding new scouring and wear on the already abnormal hard seal contact area caused by the high-flow medium. The low flow rate can be determined based on the test pipeline capacity, for example, a lower proportion of the hot-state micro-oscillation test flow rate. This proportion is not the evaluation conclusion itself; it can be set in the instruction manual according to the equipment capacity, as long as it ensures that the circumferential temperature difference of the valve seat returns to the hot-state temperature difference baseline range.

[0031] The thermal equalization verification continues until the circumferential temperature difference of the valve seat enters the baseline range of the hot temperature difference. Entering the baseline range means that the circumferential temperature difference of the valve seat is not higher than the upper limit of the baseline range and remains within this range for at least three consecutive sampling cycles. If the circumferential temperature difference of the valve seat cannot enter the baseline range of the hot temperature difference within the preset verification time, the thermal equalization verification result is marked as verification condition not met, and the thermal equalization verification is re-executed or the life node confirmation of this cycle is terminated. This setting is because a sudden increase in leakage in a high-temperature butterfly valve may be caused by instantaneous thermal deformation due to uneven heating of the valve seat circumferentially. If the influence of the circumferential temperature difference is not first ruled out, directly judging hard seal failure based on a sudden increase in leakage can easily misjudge recoverable thermal misalignment as coating wear or sealing surface damage. This embodiment, through pressure relief, retraction, and low-flow thermal equalization, allows subsequent verification of leakage and verification torque to reflect a more realistic state of the sealing pair.

[0032] After thermal equalization verification, the tested high-temperature butterfly valve is closed again according to the closing direction, closing speed, and closing torque of the previous closing process in the hot-state micro-oscillation test, and the verification leakage and verification torque are collected. If the verification leakage falls within the hot-state leakage baseline range, and the verification torque does not exceed the torque fluctuation threshold in the abnormal torque angle segment, it indicates that the leakage anomaly has been recovered after thermal equalization, and no significant torque anomaly reappears at the original abnormal contact position. Therefore, a thermal deformation misalignment type leakage result is generated. The test cycle corresponding to this result is marked as a thermal compensation abnormal cycle and is not considered a hard seal failure cycle. If the verification leakage does not fall within the hot-state leakage baseline range, and the verification torque exceeds the torque fluctuation threshold again in the abnormal torque angle segment, it indicates that the leakage has not been recovered and the abnormal torque reappears at the same contact position. Therefore, a hard seal damage type leakage result is generated, and this test cycle is marked as an unrecoverable leakage candidate cycle.

[0033] If the verified leakage amount falls within the hot leakage baseline range, but the verified torque still exceeds the torque fluctuation threshold in the abnormal torque angle segment, it indicates that the sealing result has temporarily recovered. However, there is still a risk of contact rubbing in this angle segment, generating a critical angle zone rubbing risk result. The test cycle in which this result first appears is marked as a wear warning cycle. If the verified leakage amount does not fall within the hot leakage baseline range, but the verified torque does not exceed the torque fluctuation threshold in the abnormal torque angle segment, it indicates that the leakage anomaly has not recovered. However, the anomaly does not point to the torque recurrence position of the original sealing critical angle zone. It may be related to test disturbances, metering fluctuations, non-critical position sealing conditions, or other unstable factors, generating a verification anomaly result. The test cycle is marked as a verification anomaly cycle. By using the above four judgment criteria, we can avoid simply classifying all leakage anomalies as hard seal failure and avoid ignoring the situation where the torque is abnormal but the leakage has recovered.

[0034] For candidate cycles of irreversible leakage, this embodiment does not immediately determine the hard seal life node. Instead, it continues with a hot micro-oscillation test and a thermal equilibrium verification. If subsequent test cycles generate hard seal damage leakage results again, and the abnormal torque angle segment in the subsequent test cycles is the same as the abnormal torque angle segment in the candidate cycle of irreversible leakage, it indicates that irreversible leakage and torque anomaly have occurred repeatedly at the same seal contact location. The candidate cycle of irreversible leakage is then determined as the initiation cycle of irreversible leakage, and the hard seal life node is generated accordingly. If subsequent test cycles generate hard seal damage leakage results again, but the abnormal torque angle segment is different, the subsequent test cycles are marked as new candidate cycles of irreversible leakage to avoid merging occasional anomalies at different contact locations into the same failure starting point. If subsequent test cycles do not generate hard seal damage leakage results again, the original candidate cycle of irreversible leakage is remarked as a verification anomaly cycle. Finally, a thermal compensation anomaly prompt is generated based on the thermal compensation anomaly cycle, a hard seal wear warning node is generated based on the wear warning cycle, and a repeated verification prompt is generated based on the verification anomaly cycle. When an irreversible leakage initiation cycle exists, the hard seal life node and hard seal failure judgment result are generated based on the irreversible leakage initiation cycle, and the generated content is used as the life evaluation result. When an irreversible leakage initiation cycle has not yet occurred, the life evaluation result includes the generated thermal compensation anomaly warning, hard seal wear warning node, and repeated verification warning, and outputs the result that the hard seal failure judgment condition has not been met. When an irreversible leakage initiation cycle occurs, the life evaluation result further includes the hard seal life node and hard seal failure judgment result.

[0035] Specifically, the test procedure is as follows: First, the high-temperature butterfly valve under test is kept stable at the target test temperature, and multiple hot-state closure benchmark tests are performed continuously to establish the hot-state leakage baseline range, hot-state temperature difference baseline range, torque fluctuation threshold, and leakage increment threshold. Then, the hot-state closure process is recorded, and the sealing critical angle zone is determined based on the continuous increase in closing torque and the position where the leakage returns to the baseline range. This sealing critical angle zone is then divided into multiple angle segments, and each segment is subjected to hot-state micro-oscillation. If, after micro-oscillation, the leakage increment in a certain angle segment exceeds the leakage increment threshold, the differential pressure is removed, the valve plate is retracted, and low-flow thermal equalization is performed. After the circumferential temperature difference of the valve seat returns to the hot-state temperature difference baseline range, the valve is closed again under the original closure conditions, and the leakage and torque are recorded for verification. By verifying whether the leakage has recovered and whether the torque reappears in the same abnormal torque angle segment, the leakage type is determined for this test cycle. In the above process, the reference leakage amount is used to determine the hot leakage baseline range and leakage increment threshold, the reference valve seat circumferential temperature difference is used to determine the hot temperature difference baseline range, the reference closing torque is used to determine the torque fluctuation threshold, the valve position angle is used to locate the sealing critical angle zone and abnormal torque angle segment, the disturbance leakage increment is used to trigger thermal equilibrium verification, and the verification leakage amount and verification torque are used to generate leakage type results.

[0036] In one specific embodiment, after the tested high-temperature butterfly valve is kept stable at the target test temperature, it undergoes three consecutive hot-state closure benchmark tests to obtain benchmark leakage rates of 2.0 L / min, 2.2 L / min, and 2.1 L / min, respectively. The center value of the benchmark leakage rate is taken as 2.1 L / min, the repeated acquisition fluctuation is taken as 0.2 L / min, the minimum resolution of the leakage metering device is 0.05 L / min, and the no-load leakage fluctuation of the test pipeline is 0.1 L / min. Therefore, the hot-state leakage baseline range is taken as 1.9 L / min to 2.3 L / min, and the leakage increment threshold is taken as 0.2 L / min.

[0037] The center value of the circumferential temperature difference of the reference valve seat during the heat preservation and stabilization stage is 8℃. The combined temperature acquisition error and temperature control fluctuation is 2℃, so the upper limit of the hot temperature difference baseline range is taken as 10℃. The maximum fluctuation of the reference closing torque stabilization section is 6N·m. Three times the minimum resolution of the torque acquisition device is 3N·m, and 5% of the average value of the reference closing torque stabilization section is 5N·m. Therefore, the torque fluctuation threshold is taken as 6N·m.

[0038] During the hot-state shutdown process, the incremental change in the relatively stable shutdown torque continuously exceeded 6 N·m starting at a valve position angle of 7.2°. The leakage rate entered the hot-state leakage baseline range of 1.9 L / min to 2.3 L / min at a valve position angle of 3.6°. Therefore, the angle interval between 7.2° and 3.6° was defined as the critical sealing angle region. This critical sealing angle region was divided into four angle segments, and a hot-state micro-oscillation test was conducted. In the second angle segment, the leakage rate before micro-oscillation was 2.2 L / min, and the leakage rate after micro-oscillation was 2.7 L / min, with a disturbance leakage increment of 0.5 L / min, exceeding the leakage increment threshold of 0.2 L / min. Simultaneously, the disturbance torque in this angle segment exceeded the torque fluctuation threshold; therefore, the second angle segment was recorded as the abnormal torque angle segment. Subsequently, the pressure differential was removed, the valve plate was retracted to the open side of the sealing contact position, and a high-temperature medium with a flow rate lower than that used in the hot-state micro-oscillation test was used for thermal equalization verification. After the circumferential temperature difference of the valve seat drops below 10℃ and remains stable for three consecutive sampling cycles, the tested high-temperature butterfly valve is closed again under the original closing conditions. If the verified leakage rate is 2.2 L / min and the verified torque does not exceed 6 N·m in the second angle segment, a thermal deformation misalignment type leakage result is generated. If the verified leakage rate is 2.8 L / min and the verified torque exceeds 6 N·m again in the second angle segment, a hard seal damage type leakage result is generated, and this test cycle is marked as an unrecoverable leakage candidate cycle. If the next test cycle still generates a hard seal damage type leakage result in the second angle segment, this unrecoverable leakage candidate cycle is determined as the unrecoverable leakage initiation cycle, and hard seal life node and hard seal failure judgment results are generated.

[0039] Understandably, this embodiment makes the life evaluation results no longer solely dependent on whether the final leakage exceeds the limit, but can identify whether the leakage anomaly is recoverable after thermal equalization and whether it recurs at the same sealing contact location. This embodiment reduces the risk of misjudgment in high-temperature hard seal tests: recoverable thermal misalignment is not included in the hard seal failure cycle. Only for irrecoverable leakage and torque anomalies that repeatedly occur in the same angle segment is the hard seal life node confirmed. This allows the hard seal life node to be closer to the actual damage starting point, providing a basis for judging whether the valve seat thermal compensation is insufficient, whether there is a risk of rubbing in the sealing contact angle area, and whether irrecoverable damage has occurred on the hard seal surface.

[0040] In summary, by establishing hot-state leakage baseline range, hot-state temperature difference baseline range, torque fluctuation threshold, and leakage increment threshold using hot-state shutdown benchmark data, the test judgment has its own hot-state benchmark for the same test object, reducing evaluation bias caused by differences in valve size, sealing pair processing condition, coating condition, and test temperature. The sealing critical angle zone is determined based on the position of continuous torque increase during shutdown and the position where leakage enters the hot-state leakage baseline range. This focuses the test on the critical angle range between the valve plate and valve seat from contact to clamping, rather than making a rough evaluation of the entire opening and closing stroke. This allows for more accurate capture of the sensitive stage where the hard seal pair experiences rubbing, seizing, local wear, or hot-state misalignment at the end of the shutdown. The disturbance leakage increment and abnormal torque angle segment are obtained through hot-state micro-oscillation tests. After an abnormal leakage occurs, the hard seal is not directly judged as failing. Instead, the valve plate is returned to the open side position outside the sealing critical angle zone, and a high-temperature medium is introduced for thermal equalization verification. Whether the circumferential temperature difference of the valve seat returns to the hot-state temperature difference baseline range is used to eliminate false leakage anomalies caused by instantaneous thermal deformation or uneven temperature distribution. After thermal equilibrium verification, the tested high-temperature butterfly valve is closed again. By combining the verification of whether the leakage has recovered and whether the verification torque exceeds the torque fluctuation threshold again in the abnormal torque angle range, leakage type results and life evaluation results are generated. This distinguishes between recoverable thermal misalignment, critical angle contact abnormality and irreversible hard seal damage, avoiding the simple classification of leakage abnormalities caused by different reasons into the same failure conclusion, and improving the accuracy of hard seal life evaluation of high-temperature butterfly valves.

[0041] Based on another preferred embodiment described above, see [link to preferred embodiment]. Figure 3 As shown, this embodiment provides a high-temperature butterfly valve hard seal test and evaluation system for applying the above-mentioned high-temperature butterfly valve hard seal test and evaluation method, including: The acquisition unit is configured to acquire the hot-state closing reference data, hot-state closing process data, hot-state micro-oscillation test data, and thermal equilibrium verification data of the tested high-temperature butterfly valve.

[0042] The processing unit is configured to process the hot shut-off baseline data to obtain the hot leakage baseline range, hot temperature difference baseline range, torque fluctuation threshold and leakage increment threshold, determine the sealing critical angle zone based on the hot shut-off process data, and obtain the disturbance leakage increment and abnormal torque angle segment based on the hot micro-oscillation test data.

[0043] The verification unit is configured to control the valve plate to retract and allow high-temperature medium to be introduced when the disturbance leakage increment exceeds the leakage increment threshold, in order to perform thermal equilibrium verification.

[0044] The evaluation unit is configured to generate leakage type results based on the verified leakage amount and verified torque, and to generate life evaluation results based on the leakage type results.

[0045] It is understandable that the above-mentioned high-temperature butterfly valve hard seal test evaluation method and system have the same beneficial effects, and will not be elaborated here.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for evaluating the hard seal of a high-temperature butterfly valve, characterized in that, include: Collect hot-state shut-off baseline data of the tested high-temperature butterfly valve, process the hot-state shut-off baseline data to obtain the hot-state leakage baseline range, hot-state temperature difference baseline range, torque fluctuation threshold and leakage increment threshold; The valve position angle, closing torque, and leakage amount are collected during the hot-state closing process of the tested high-temperature butterfly valve. Based on the continuously rising position of the closing torque and the position where the leakage amount enters the hot-state leakage baseline range, the sealing critical angle zone is determined. A hot micro-oscillation test was conducted in the critical sealing angle region to obtain the disturbance leakage increment and abnormal torque angle range. When the disturbance leakage increment exceeds the leakage increment threshold, the valve plate is moved back to the open side position outside the sealing critical angle region, and a high-temperature medium is introduced for thermal equilibrium verification until the circumferential temperature difference of the valve seat enters the hot temperature difference baseline range. After thermal equilibrium verification, the tested high-temperature butterfly valve is closed again, and the verification leakage amount and verification torque are collected. Based on whether the verification leakage amount enters the hot leakage baseline range and whether the verification torque exceeds the torque fluctuation threshold in the abnormal torque angle range, a leakage type result is generated, and a life evaluation result is generated based on the leakage type result.

2. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 1, characterized in that, When acquiring hot-state shutdown baseline data to obtain the hot-state leakage baseline range, the hot-state temperature difference baseline range, the torque fluctuation threshold, and the leakage increment threshold, the following is included: After the tested high-temperature butterfly valve reaches the test temperature and stabilizes, the hot-state closing reference data is collected. The hot-state closing reference data includes the reference leakage, the reference valve seat circumferential temperature difference, and the reference closing torque. The hot leakage baseline range and the leakage increment threshold are obtained based on the reference leakage amount, the hot temperature difference baseline range is obtained based on the reference valve seat circumferential temperature difference, and the torque fluctuation threshold is obtained based on the reference closing torque.

3. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 1, characterized in that, Determining the critical sealing angle region includes: The valve position angle, the closing torque, and the leakage amount are continuously collected along the closing direction; The position where the increment of the relatively stable closing torque first continuously exceeds the torque fluctuation threshold is determined as the sealing contact position, the position where the leakage enters the hot leakage baseline range is determined as the sealing clamping position, and the angle range between the sealing contact position and the sealing clamping position is determined as the sealing critical angle region.

4. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 3, characterized in that, The hot micro-oscillation test in the critical sealing angle region includes: The critical sealing angle region is divided into multiple angle segments. Reciprocating micro-oscillation is performed in each angle segment. The leakage before micro-oscillation, the leakage after micro-oscillation, and the disturbance torque are collected, and the hot micro-oscillation test flow rate is recorded. The difference between the leakage after micro-oscillation and the leakage before micro-oscillation is taken as the disturbance leakage increment. The angle segment in which the disturbance torque exceeds the torque fluctuation threshold is taken as the abnormal torque angle segment.

5. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 4, characterized in that, The thermal equilibrium verification process includes: When the disturbance leakage increment exceeds the leakage increment threshold, the pressure difference of the tested high-temperature butterfly valve is removed, and the valve plate is retracted to the open side of the sealing contact position, so that the valve plate is released from the compressed state of the valve seat; a high-temperature medium with a flow rate lower than that of the hot micro-oscillation test is passed through the gap between the valve plate and the valve seat until the circumferential temperature difference of the valve seat enters the hot temperature difference baseline range.

6. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 1, characterized in that, When generating leak type results, the following are included: When the verified leakage amount enters the hot leakage baseline range, and the verified torque does not exceed the torque fluctuation threshold in the abnormal torque angle segment, a thermal deformation misalignment type leakage result is generated; When the verified leakage amount does not fall within the hot leakage baseline range, and the verified torque exceeds the torque fluctuation threshold in the abnormal torque angle segment, a hard seal damage type leakage result is generated; When the verified leakage amount enters the hot leakage baseline range, and the verified torque exceeds the torque fluctuation threshold in the abnormal torque angle segment, a critical angle zone scuff risk result is generated; When the verified leakage amount does not fall within the hot leakage baseline range and the verified torque does not exceed the torque fluctuation threshold in the abnormal torque angle segment, a verification abnormal result is generated.

7. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 6, characterized in that, When generating life assessment results based on the leakage type results, the following are included: The test cycle that generates the thermal deformation misalignment leakage result is marked as a thermal compensation abnormal cycle and is not considered as a hard seal failure cycle. The test cycle that first generates the collision risk result of the critical corner area is marked as a wear warning cycle; The test cycle that generates the aforementioned review anomaly result is marked as a review anomaly cycle; The test cycle that generates the hard seal damage-type leakage result is marked as an irreversible leakage candidate cycle; Based on the thermal compensation abnormal cycle, the wear warning cycle, the verification abnormal cycle, and the unrecoverable leakage candidate cycle, a life evaluation result is generated.

8. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 7, characterized in that, When confirming the candidate cycle for irreversible leakage, the process includes: performing a hot micro-oscillation test and a thermal equilibrium verification after the candidate cycle for irreversible leakage; if subsequent test cycles generate the hard seal damage type leakage result again, and the abnormal torque angle segment in the subsequent test cycles is the same as the abnormal torque angle segment in the candidate cycle for irreversible leakage, then the candidate cycle for irreversible leakage is determined as the initiation cycle for irreversible leakage, and a hard seal life node is generated based on the initiation cycle for irreversible leakage; if subsequent test cycles generate the hard seal damage type leakage result again, but the abnormal torque angle segment in the subsequent test cycles is different from the abnormal torque angle segment in the candidate cycle for irreversible leakage, then the subsequent test cycles are marked as new candidate cycles for irreversible leakage; if subsequent test cycles do not generate the hard seal damage type leakage result again, then the candidate cycle for irreversible leakage is remarked as a verification abnormal cycle.

9. The method for evaluating the hard seal of a high-temperature butterfly valve according to claim 8, characterized in that, Generating the life assessment results includes: A thermal compensation anomaly alert is generated based on the thermal compensation anomaly cycle; a hard seal wear warning node is generated based on the wear warning cycle; and a re-verification alert is generated based on the verification anomaly cycle. When an irreversible leakage initiation cycle exists, a hard seal life node and a hard seal failure determination result are generated based on the irreversible leakage initiation cycle. The generated thermal compensation anomaly alert, hard seal wear warning node, re-verification alert, hard seal life node, and hard seal failure determination result are used as the life evaluation result.

10. A high-temperature butterfly valve hard seal test and evaluation system, used for applying the high-temperature butterfly valve hard seal test and evaluation method as described in any one of claims 1-9, characterized in that, include: The data acquisition unit is configured to acquire the hot-state closing reference data, hot-state closing process data, hot-state micro-oscillation test data, and thermal equilibrium verification data of the tested high-temperature butterfly valve. The processing unit is configured to process the hot shut-off reference data to obtain the hot leakage baseline range, the hot temperature difference baseline range, the torque fluctuation threshold and the leakage increment threshold, determine the sealing critical angle zone based on the hot shut-off process data, and obtain the disturbance leakage increment and abnormal torque angle segment based on the hot micro-oscillation test data. The verification unit is configured to control the valve plate to retract and allow high-temperature medium to be introduced when the disturbance leakage increment exceeds the leakage increment threshold, so as to perform thermal equalization verification. The evaluation unit is configured to generate a leakage type result based on the verified leakage amount and verified torque, and to generate a life evaluation result based on the leakage type result.

Images