CN-122016197-A - Method and system for detecting internal leakage of positive pressure helium detection valve

CN122016197ACN 122016197 ACN122016197 ACN 122016197ACN-122016197-A

Abstract

The invention provides a method and a system for detecting internal leakage of a positive pressure helium detection valve, and relates to the technical field of valve sealing performance detection, wherein the method comprises the steps of applying test gas with rated working pressure to a valve to be detected, monitoring internal pressure change of the valve in real time under the rated working pressure, and performing positive pressure internal leakage pre-detection; and based on the judging result of the passing of the pre-detection, controlling the temperature condition of the valve to be tested in the continuous application process of the test gas, repeatedly executing the positive pressure internal leakage test at different temperatures, and recording the basic leakage rate at each temperature point to obtain an initial dynamic sealing performance curve. The invention can realize the accurate correction and multidimensional data fusion of the valve leakage rate detection data and improve the accuracy of the internal leakage detection of the valve under the temperature alternating working condition.

Inventors

XUE HUI
LI YUNFEI
Ding Zhaozhao

Assignees

上海聚克流体控制有限公司

Dates

Publication Date: 20260512
Application Date: 20260410

Claims (9)

1. The method for detecting the internal leakage of the positive pressure helium detection valve is characterized by comprising the following steps of: step 1, applying test gas with rated working pressure to a valve to be tested, monitoring the internal pressure change of the valve in real time under the rated working pressure, and performing positive pressure internal leakage pre-detection; step 2, controlling the temperature condition of the valve to be tested in the continuous application process of the test gas based on the judgment result of the pre-detection, repeatedly executing positive pressure internal leakage test at different temperatures, and recording the basic leakage rate at each temperature point to obtain an initial dynamic sealing performance curve; step 3, synchronously arranging a plurality of characteristic space marking points at a sealing interface of the outer surface of the valve, collecting three-dimensional space coordinates of each characteristic space marking point in real time, fitting the three-dimensional space coordinates into a space closed curved surface, and calculating the area deformation rate of the space closed curved surface relative to the initial state to obtain a coefficient of a few He Baozhen degrees of the sealing interface at a corresponding temperature; step 4, performing helium mass spectrum leak detection at each temperature point, scanning the outer surface of the valve, capturing tracer gas molecules escaping from the leak, and obtaining original leak rate detection data at the corresponding temperature point; And 5, compensating and correcting the original leak rate detection data at the corresponding temperature points by taking the geometric fidelity coefficient at the same temperature point as a correction factor to obtain corrected leak rate detection results, and fusing the corrected leak rate detection results at the temperature points with the initial dynamic sealing performance curve to obtain a temperature-corrected leak rate correlation curve.
2. The method for detecting the internal leakage of the positive pressure helium detection valve according to claim 1, wherein the method is characterized in that test gas with rated working pressure is applied to the valve to be detected, the internal pressure change of the valve is monitored in real time under the rated working pressure after the pressure is stabilized, the positive pressure internal leakage pre-detection is carried out, if the pressure is kept stable, a judgment result passing the pre-detection is obtained, and if the pressure fluctuation exceeds a set threshold value, the test is terminated and an alarm signal is sent, and the method comprises the following steps: filling test gas into the valve to be tested until the internal pressure of the valve reaches the rated working pressure, and stopping filling after the internal pressure of the valve reaches the rated working pressure to obtain an initial stable pressure value; continuously collecting pressure data in the valve based on the initial stable pressure value, and simultaneously calculating the pressure fluctuation amplitude between the current pressure value and the initial stable pressure value in real time in a preset sampling period; and comparing the pressure fluctuation amplitude with a set threshold, if the pressure fluctuation amplitude is always lower than the set threshold in a preset monitoring period, judging that the pressure is stable, obtaining a judgment result passing the pre-detection, and if the pressure fluctuation amplitude exceeds the set threshold in the preset monitoring period, judging that the pressure fluctuation exceeds an allowable range, immediately stopping the test, and outputting an alarm signal.
3. The method for detecting internal leakage of a positive pressure helium test valve according to claim 2, wherein based on the determination result of passing the preliminary detection, the temperature condition of the valve to be tested is controlled during the continuous application of the test gas, the positive pressure internal leakage test is repeatedly performed at different temperatures, the basic leakage rate at each temperature point is recorded, and an initial dynamic sealing performance curve of the leakage rate along with the temperature change is obtained, comprising: After a judging result passing the pre-detection is obtained, the internal test gas pressure of the valve is kept in a rated working pressure state, and a temperature control sequence is set, wherein the temperature control sequence comprises a plurality of target temperature points which are increased or decreased according to a preset step length; Sequentially adjusting the environmental temperature of the valve to each target temperature point, and continuously collecting pressure decay data of the internal pressure of the valve along with the change of time after each target temperature point reaches heat balance; according to the pressure attenuation data collected at each target temperature point, calculating the basic leakage rate corresponding to the temperature point, and obtaining the corresponding relation between each target temperature point and the basic leakage rate; and performing curve fitting on the basic leakage rate at each target temperature point by taking the target temperature point as an abscissa and the basic leakage rate as an ordinate to form an initial dynamic sealing performance curve of the leakage rate along with the temperature change.
4. The method for detecting internal leakage of a positive pressure helium detection valve according to claim 3, wherein a plurality of characteristic space marking points are synchronously distributed at a sealing interface of an outer surface of the valve, three-dimensional space coordinates of the characteristic space marking points are collected in real time and are used for fitting into a space closed curved surface, the area deformation rate of the space closed curved surface relative to an initial state is calculated, and a coefficient of a few He Baozhen degrees of the sealing interface at a corresponding temperature is obtained, and the method comprises the following steps: The method comprises the steps of calling a temperature control sequence which is set for a valve to be tested from a control end, acquiring the set temperature control sequence, and before executing positive pressure internal leakage test of each target temperature point, acquiring initial three-dimensional space coordinates of a plurality of characteristic space marking points at a sealing interface of the outer surface of the valve, wherein the characteristic space marking points are distributed in a contact ring belt area of a sealing surface of a valve seat and a valve clack and a boundary circumferential line area of a valve rod and a stuffing box; in the process of executing positive pressure internal leakage test on each target temperature point, after the target temperature points reach heat balance, synchronously collecting real-time three-dimensional space coordinates of the same group of characteristic space marking points at the current temperature; Carrying out space matching on the real-time three-dimensional space coordinates acquired at the current temperature and the initial three-dimensional space coordinates, and respectively fitting an initial space closed curved surface and a current space closed curved surface; And calculating the area deformation rate of the current space closed curved surface relative to the initial space closed curved surface, and taking the area deformation rate as the geometric fidelity coefficient of the sealing interface at the current target temperature point to obtain a few He Baozhen-degree coefficient of the sealing interface at the corresponding temperature.
5. The method for detecting the internal leakage of the positive pressure helium detection valve according to claim 4, wherein at each temperature point, scanning the outer surface of the valve by adopting a helium mass spectrum leakage detection mode, capturing tracer gas molecules escaping from the leakage, and obtaining original leakage rate detection data at the corresponding temperature point, wherein the method comprises the following steps: Acquiring a plurality of He Baozhen-degree coefficients of a sealing interface obtained at each target temperature point at a corresponding temperature, and starting a helium mass spectrum leakage detection flow after executing a positive pressure internal leakage test at the temperature point and achieving heat balance for each target temperature point; moving along a preset scanning path on the outer surface of the valve, and continuously scanning the outer surface of the valve to capture the concentration signal of trace gas molecules escaping from the leakage point in real time; Converting the captured trace gas molecular concentration signal into a leak rate value to obtain original leak rate detection data at the current temperature point; And (3) associating and storing the original leak rate detection data at the current temperature point with the geometric fidelity coefficient at the temperature point to form a corresponding relation between each target temperature point and the original leak rate detection data.
6. The method for detecting internal leakage of a positive pressure helium test valve according to claim 5, wherein the geometric fidelity coefficient at the same temperature point is used as a correction factor, the original leakage rate detection data at the corresponding temperature point is compensated and corrected to obtain corrected leakage rate detection results, the corrected leakage rate detection results at each temperature point are fused with the initial dynamic sealing performance curve to obtain a temperature-corrected leakage rate correlation curve, and the output of the test results is completed, comprising: Acquiring the corresponding relation between each formed target temperature point and the original leak rate detection data, and simultaneously acquiring the obtained initial dynamic sealing performance curve; Extracting original leak rate detection data and a corresponding geometric fidelity coefficient at each target temperature point, taking a plurality of He Baozhen-degree coefficients as correction factors, and compensating and correcting the original leak rate detection data according to a compensation and correction function positively correlated with the geometric fidelity coefficient to obtain corrected leak rate detection results at the temperature points; Fusing the corrected leak rate detection result at each target temperature point with the initial dynamic sealing performance curve at the same temperature coordinate, namely taking the corrected leak rate detection result as the real leak rate at the temperature point, replacing the original basic leak rate value of the corresponding temperature point in the initial dynamic sealing performance curve, and carrying out smooth interpolation on adjacent temperature points to reconstruct a new temperature-corrected leak rate correlation curve; and outputting the temperature-corrected leak rate correlation curve as a test result.
7. A positive pressure helium detection valve leak detection system implementing the method of any one of claims 1 to 6, comprising: The positive pressure internal leakage pre-detection module is used for applying test gas with rated working pressure to the valve to be detected, monitoring the internal pressure change of the valve in real time under the rated working pressure, and carrying out positive pressure internal leakage pre-detection; the dynamic working condition simulation module is used for controlling the temperature condition of the valve to be tested in the continuous application process of the test gas based on the judgment result of the pre-detection, repeatedly executing positive pressure internal leakage test at different temperatures, and recording the basic leakage rate at each temperature point to obtain an initial dynamic sealing performance curve of the leakage rate along with the temperature change; The sealing interface deformation detection module is used for synchronously arranging a plurality of characteristic space marking points at a sealing interface of the outer surface of the valve, collecting three-dimensional space coordinates of each characteristic space marking point in real time, fitting the three-dimensional space coordinates into a space closed curved surface, calculating the area deformation rate of the space closed curved surface relative to the initial state, and obtaining a coefficient of a few He Baozhen degrees of the sealing interface at the corresponding temperature; The helium mass spectrum leakage detection module is used for executing helium mass spectrum leakage detection at each temperature point, scanning the outer surface of the valve, capturing tracer gas molecules escaping from leakage, and obtaining original leakage rate detection data at the corresponding temperature point; The data processing and fusing module is used for compensating and correcting the original leak rate detection data at the corresponding temperature points by taking the geometric fidelity coefficient at the same temperature point as a correction factor to obtain corrected leak rate detection results, fusing the corrected leak rate detection results at the temperature points with the initial dynamic sealing performance curve, namely taking the corrected leak rate detection results as the actual leak rate at the temperature points, replacing the original basic leak rate value of the corresponding temperature points in the initial dynamic sealing performance curve, carrying out smooth interpolation on adjacent temperature points, reconstructing a new temperature-corrected leak rate correlation curve, and completing the output of the test result.
8. A computing device, comprising: one or more processors; storage means for storing one or more programs which when executed by the one or more processors cause the one or more processors to implement the method of any of claims 1 to 6.
9. A computer readable storage medium, characterized in that the computer readable storage medium has stored therein a program which, when executed by a processor, implements the method according to any of claims 1 to 6.

Description

Method and system for detecting internal leakage of positive pressure helium detection valve Technical Field The invention relates to the technical field of valve sealing performance detection, in particular to a method and a system for detecting internal leakage of a positive pressure helium detection valve. Background In the field of detection of sealing performance of industrial valves, a positive pressure helium detection technology becomes a main flow technical means of detecting leakage in the valves due to the tracing characteristic of helium, and is widely applied to the fields of energy sources, aerospace and the like with strict requirements on the sealing reliability of the valves. When the existing positive pressure helium detection valve internal leakage detection method is used for carrying out temperature working condition simulation detection on the valve, the related leakage rate data is obtained only through pressure monitoring and helium mass spectrum scanning, and the technical defect that the influence of geometrical deformation of a valve sealing interface caused by temperature change on a leakage rate detection result is not considered is generally faced. Because the leak rate data obtained by detection are uncorrected original data, whether the leak rate change is caused by the failure of the actual sealing performance of the valve or the geometric deformation caused by the expansion and contraction of a sealing interface is difficult to distinguish, the leak rate detection result has deviation from the actual sealing state of the valve, and accurate quantitative evaluation of tiny internal leakage is difficult to realize. Meanwhile, the existing detection method has the problem that the basic leak rate data of positive pressure internal leak pre-detection and the leak rate data of helium mass spectrum leak detection are not effectively fused, the detection data are only output in a single dimension, a correlation analysis curve of temperature-leak rate is difficult to form, the sealing performance evolution characteristic of the valve under the temperature change is difficult to effectively represent from a dynamic view angle, and the reference value of the detection data to the operation and maintenance decision of the valve is reduced. Disclosure of Invention The invention provides a detection method and a detection system for internal leakage of a positive pressure helium detection valve, which can realize accurate correction of valve leakage rate detection data and multi-dimensional data fusion, improve the accuracy of internal leakage detection of the valve under a temperature alternating working condition and provide a basis for valve sealing performance evaluation and long-term operation leakage trend pre-judgment. In order to solve the technical problems, the technical scheme of the invention is as follows: in a first aspect, a method for detecting an internal leak of a positive pressure helium test valve, the method comprising: Applying test gas with rated working pressure to the valve to be tested, monitoring the internal pressure change of the valve in real time under the rated working pressure, and performing positive pressure internal leakage pre-detection; Based on the judging result of the pre-detection, controlling the temperature condition of the valve to be tested in the continuous application process of the test gas, repeatedly executing positive pressure internal leakage test at different temperatures, and recording the basic leakage rate at each temperature point to obtain an initial dynamic sealing performance curve of the leakage rate along with the temperature change; in the process of executing the test of each temperature point, a plurality of characteristic space marking points are synchronously distributed at a sealing interface of the outer surface of the valve, three-dimensional space coordinates of each characteristic space marking point are collected in real time and are used for fitting into a space closed curved surface, the area deformation rate of the space closed curved surface relative to the initial state is calculated, and a coefficient of a few He Baozhen degrees of the sealing interface at the corresponding temperature is obtained; Scanning the outer surface of the valve in a helium mass spectrum leak detection mode at each temperature point, capturing tracer gas molecules escaping from leakage, and executing helium mass spectrum leak detection to obtain original leak rate detection data at the corresponding temperature point; and taking the geometric fidelity coefficient at the same temperature point as a correction factor, carrying out compensation correction on the original leak rate detection data at the corresponding temperature point according to a compensation correction function positively correlated with the geometric fidelity coefficient to obtain corrected leak rate detection results, fusing the corrected leak rate detection resul