A method and apparatus for predicting the lifespan of a solenoid valve.

Abstract

This invention relates to a method and apparatus for predicting the lifespan of solenoid valves, applicable to normally excited or de-excited solenoid valves. The method includes the following steps: identifying key components of the solenoid valve; performing aging tests and analysis on the coil, and determining the coil's lifespan based on the analysis results; performing compression deformation and aging tests on the rubber seal, and determining the rubber seal's lifespan based on the test results; performing stress relaxation tests and assessments on the spring, and determining the spring's lifespan based on the test results; and predicting the lifespan of the solenoid valve based on the coil's lifespan, the rubber seal's lifespan, and the spring's lifespan. This invention can effectively assess the effective service life of normally de-excited or excited solenoid valves, improving the accuracy of lifespan prediction for normally de-excited or excited solenoid valves in industrial production processes. It can also improve the equipment management level of power plants for this type of solenoid valve, enabling the development of appropriate maintenance strategies and improving the economic efficiency and safety of power plant production.

Description

Technical Field

[0001] This invention relates to the technical field of solenoid valve life prediction, and more specifically, to a method and apparatus for predicting the life of a solenoid valve. Background Technology

[0002] A solenoid valve is an automatic control device based on the principle of electromagnetic force. It controls the flow and direction of a medium by switching on and off using a current signal, thereby controlling the main equipment. Solenoid valves are widely used in industrial automation production processes, mainly for controlling the opening, closing, and flow direction of gas or liquid media.

[0003] Nuclear power plants use a large number of solenoid valves as control and protection devices. The function of some solenoid valves directly affects the production and safety of the power plant. At present, the preventive maintenance methods for solenoid valves are mainly parameter checks and periodic replacements. However, the methods for predicting the lifespan (replacement cycle) of solenoid valves for different environments and uses are relatively simple and lacking.

[0004] Currently, most market-based predictions for solenoid valve lifespan focus on the valve's operational lifespan, defining its service life by the number of reliable actuations. This method is suitable for solenoid valves with frequent control functions, but it's inaccurate for valves operating under normal energization or de-energization. For example, the turbine trip solenoid valve in a nuclear power plant is continuously energized during normal operation, only de-energizing and tripping when an abnormal situation occurs and a trip signal is triggered. This valve operates no more than a handful of times per year, and the typical lifespan of a solenoid valve ranges from tens of thousands to millions of cycles. If the lifespan of a trip solenoid valve is predicted based on its operational lifespan, its lifespan would be over a thousand years, clearly inconsistent with the actual lifespan of nuclear power plant trip solenoid valves. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method and device for predicting the lifespan of a solenoid valve, addressing the problems existing in the prior art.

[0006] The technical solution adopted by this invention to solve its technical problem is: to construct a life prediction method for solenoid valves, applicable to normally excited solenoid valves or de-excited solenoid valves, including the following steps:

[0007] Identify the key components of the solenoid valve; these key components include: coil, rubber seal, and spring.

[0008] An aging test and analysis are performed on the coil, and the lifespan of the coil is determined based on the analysis results;

[0009] Perform compression deformation and aging tests on the rubber seal, and determine the life of the rubber seal based on the test results;

[0010] Perform stress relaxation tests on the spring and determine the life of the spring based on the test results;

[0011] The lifespan of the solenoid valve is predicted based on the lifespan of the coil, the lifespan of the rubber seal, and the lifespan of the spring.

[0012] In the life prediction method for solenoid valves described in this invention, the determination of key components of the solenoid valve includes:

[0013] Obtain the component information and structural information of the solenoid valve;

[0014] The key components are determined based on the component information and the structural information.

[0015] In the life prediction method for the solenoid valve described in this invention, the step of performing an aging test and analysis on the coil, and determining the life of the coil based on the analysis results, includes:

[0016] The magnetic induction intensity of the coil was tested.

[0017] After completing the magnetic induction intensity test, the initial data of the coil are collected;

[0018] The coil was subjected to a high and low temperature alternating aging test;

[0019] Collect aging data of the coil during the aging test;

[0020] The lifespan of the coil is evaluated based on the initial data and the aging data to obtain the lifespan of the coil.

[0021] In the life prediction method for the solenoid valve described in this invention, the initial data includes: initial DC resistance, initial insulation resistance, and initial excitation temperature;

[0022] The aging data includes: aging DC resistance, aging insulation resistance, and temperature during aging excitation.

[0023] The step of evaluating the lifespan of the coil based on the initial data and the aging data to obtain the lifespan of the coil includes:

[0024] The critical value of the coil aging state is determined based on the initial DC resistance, the initial insulation resistance, the aged DC resistance, and the aged insulation resistance.

[0025] The test time is determined based on the critical value of the aging state.

[0026] The lifespan of the coil is calculated based on the initial excitation temperature, the aging excitation temperature, and the test time.

[0027] In the life prediction method for the solenoid valve described in this invention, the step of performing compression deformation and aging tests on the rubber seal and determining the life of the rubber seal based on the test results includes:

[0028] Obtain the initial height of the rubber seal;

[0029] An aging test is performed on the rubber seal, and the aging height of the rubber seal is obtained after aging is completed. The aging test temperature of the rubber seal is also recorded during the aging process. The aging height is the height of the rubber seal after the aging test is completed.

[0030] Determine the evaluation parameters and failure criteria for the rubber seal; the evaluation parameter is the compression set.

[0031] After determining the evaluation parameters, the test compression ratio of the rubber seal is calculated based on the initial height and the aging height, or the test compression ratio of the rubber seal is determined based on a reference standard.

[0032] The critical time is determined based on the experimental compression ratio and the failure criterion.

[0033] The lifespan of the rubber seal is calculated based on the critical time and the aging test temperature.

[0034] In the life prediction method for the solenoid valve described in this invention, obtaining the initial height of the rubber seal includes:

[0035] Place the rubber seal in the compression clamp;

[0036] Under standard test conditions, allow to stand for the first preset time;

[0037] After opening the compression clamp, let it stand for a second preset time, and measure the current height of the rubber seal; the current height is the initial height of the rubber seal.

[0038] In the life prediction method for the solenoid valve described in this invention, the step of performing an aging test on the rubber seal and obtaining the aging height of the rubber seal after aging includes:

[0039] The rubber seal is placed in a compression set fixture;

[0040] The entire compression set fixture was placed in an aging chamber for aging.

[0041] After the aging time is reached, the compression set fixture is removed from the aging chamber, and the rubber seal is removed from the compression set fixture.

[0042] After a preset time period, the height of the rubber seal is measured to obtain the aging height of the rubber seal.

[0043] In the life prediction method for the solenoid valve described in this invention, the step of performing a stress relaxation test on the spring and determining the life of the spring based on the test results includes:

[0044] A dual-threaded single-loop loading scheme is used to compress the spring, so that the spring is compressed to the target deformation amount and then held for a fourth preset time.

[0045] Perform a heating test on the spring, and hold the spring at the target temperature for a fifth preset time;

[0046] Repeat the heating test described above and record multiple temperature data of the spring under the target deformation.

[0047] Multiple load decay curves of the spring are determined based on the multiple temperature data and the target deformation.

[0048] The lifespan of the spring is calculated based on the multiple load attenuation curves.

[0049] In the method for predicting the lifespan of a solenoid valve according to the present invention, predicting the lifespan of the solenoid valve based on the lifespan of the coil, the lifespan of the rubber seal, and the lifespan of the spring includes:

[0050] The lifespan of the coil, the lifespan of the rubber seal, and the lifespan of the spring are compared to determine the minimum lifespan.

[0051] The lifespan of the solenoid valve is predicted based on the minimum value of the lifespan.

[0052] The present invention also provides a life prediction device for a solenoid valve, comprising:

[0053] A key component identification unit is used to identify the key components of the solenoid valve; the key components include: coil, rubber seal, and spring.

[0054] A coil life analysis unit is used to perform aging tests and analyses on the coil and determine the life of the coil based on the analysis results.

[0055] A rubber seal analysis unit is used to perform compression deformation and aging tests on the rubber seal and determine the life of the rubber seal based on the test results.

[0056] The spring life analysis unit is used to perform stress relaxation tests and assessments on the spring, and determine the life of the spring based on the test results.

[0057] A life prediction unit is used to predict the life of the solenoid valve based on the life of the coil, the life of the rubber seal, and the life of the spring.

[0058] The method and apparatus for predicting the lifespan of solenoid valves according to the present invention have the following beneficial effects: The method includes the following steps: identifying the key components of the solenoid valve; performing aging tests and analysis on the coil, and determining the coil's lifespan based on the analysis results; performing compression deformation and aging tests on the rubber seal, and determining the rubber seal's lifespan based on the test results; performing stress relaxation tests and assessments on the spring, and determining the spring's lifespan based on the test results; and predicting the lifespan of the solenoid valve based on the coil's lifespan, the rubber seal's lifespan, and the spring's lifespan. This invention can effectively assess the effective service life of normally de-excited or excitation-excited solenoid valves, improving the accuracy of lifespan prediction for normally de-excited or excitation-excited solenoid valves in industrial production processes. It can also improve the equipment management level of power plants for this type of solenoid valve, enabling the development of appropriate maintenance strategies and improving the economic efficiency and safety of power plant production. Attached Figure Description

[0059] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0060] Figure 1 This is a flowchart illustrating the life prediction method for solenoid valves provided by the present invention.

[0061] Figure 2 This is a flowchart of the life evaluation test for the solenoid valve coil provided by the present invention;

[0062] Figure 3 This is a cross-sectional view of the life test of the solenoid valve coil provided by the present invention;

[0063] Figure 4 This is a flowchart of the life evaluation test for the rubber seal of the solenoid valve provided by the present invention;

[0064] Figure 5 This is a schematic diagram of the life prediction device for solenoid valves provided by the present invention. Detailed Implementation

[0065] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] In nuclear power plants, a large number of solenoid valves used for protection functions are in a state of normal excitation or demagnetization. They only operate when the corresponding protection signal is triggered, and their operating frequency is very low. Conventional life prediction methods based on the number of operations cannot accurately predict the life of such solenoid valves. Moreover, the functions of protection solenoid valves are very important and closely related to safety. Therefore, studying the aging failure modes of solenoid valves under normal excitation or demagnetization conditions, establishing life assessment methods and models, and realizing the life prediction of solenoid valves under normal excitation or demagnetization conditions are crucial to the economy and safety of industrial production.

[0067] To address the shortcomings of existing life prediction schemes for solenoid valves under normal excitation or demagnetization conditions, this invention provides a life prediction method applicable to solenoid valves under normal excitation or demagnetization conditions. This method predicts the service life of the solenoid valve by analyzing the life of key components of the solenoid valve under static operating conditions.

[0068] Specifically, such as Figure 1 As shown, the life prediction method for this solenoid valve includes the following steps:

[0069] Step S101: Identify the key components of the solenoid valve.

[0070] In this embodiment of the invention, the key components are the easily aging parts of the solenoid valve. These key components include: a coil, a rubber seal, and a spring. Alternatively, in some other embodiments, if the solenoid valve does not contain a spring, it is not necessary to analyze the spring's lifespan; only the lifespan of the coil and the rubber seal needs to be analyzed. In this case, the final lifespan prediction of the solenoid valve is based on the lifespan of the coil and the rubber seal.

[0071] In this embodiment of the invention, determining the key components of a solenoid valve includes: acquiring component information and structural information of the solenoid valve; and determining the key components based on the component and structural information. The component information of the solenoid valve refers to all components included in the solenoid valve, such as coils, rubber seals, and springs. The structural information of the solenoid valve refers to its specific structure. By analyzing the component and structural information of the solenoid valve, the easily aging components, i.e., the key components, can be identified.

[0072] Step S102: Perform aging tests and analyses on the coil, and determine the coil's lifespan based on the analysis results.

[0073] In this embodiment of the invention, performing aging tests and analyses on the coil and determining the coil's lifespan based on the analysis results includes: conducting a magnetic induction intensity test on the coil; collecting initial data of the coil after completing the magnetic induction intensity test; conducting a high and low temperature alternating aging test on the coil; collecting aging data of the coil during the aging test; and evaluating the coil's lifespan based on the initial data and aging data to obtain the coil's lifespan.

[0074] The initial data includes: initial DC resistance, initial insulation resistance, and initial excitation temperature; the aging data includes: aging DC resistance, aging insulation resistance, and aging excitation temperature; the coil life is evaluated based on the initial and aging data to obtain the coil life, including: determining the critical value of the coil aging state based on the initial DC resistance, initial insulation resistance, aging DC resistance, and aging insulation resistance; determining the test time based on the critical value of the aging state; and calculating the coil life based on the initial excitation temperature, aging excitation temperature, and test time.

[0075] Specifically, such as Figure 2 As shown, firstly, the magnetic induction intensity of the coil is tested. Specifically, the coil is energized, and a gaussmeter is used to check if the solenoid valve coil generates magnetic force. If not, the solenoid valve is considered damaged and cannot undergo a life test. If magnetic force is generated, the life test can proceed. At this point, initial data needs to be collected, specifically using a high-precision multimeter, thermometer, and super insulation meter to measure the DC resistance, insulation resistance, and excitation temperature of the solenoid valve coil before accelerated aging—that is, the initial DC resistance, initial insulation resistance, and initial excitation temperature. Next, the coil undergoes a high-low temperature alternating aging test. Generally, a high-low temperature alternating damp heat test chamber is used to provide the aging environment for the coil for a total of 1200 hours. During the aging process, status indicators are collected, specifically using a high-precision multimeter, thermometer, and super insulation meter to measure the DC resistance, insulation resistance, and excitation temperature of the coil at the end of aging—that is, the aging DC resistance, aging insulation resistance, and aging excitation temperature. Finally, the initial DC resistance, initial insulation resistance, initial excitation temperature, aging DC resistance, aging insulation resistance, and aging excitation temperature are substituted into the life assessment model for calculation to obtain the coil's life.

[0076] Among them, the test profile of the high and low temperature alternating aging test is as follows: Figure 3 As shown.

[0077] During the aging test, the aging status indicators of the solenoid valve coil are measured periodically, specifically the DC resistance and insulation resistance of the coil. These measurements are then compared with the initial DC resistance and insulation resistance. The effective lifespan of the solenoid valve coil is calculated based on the test time at which a significant decrease in either the DC resistance or insulation resistance occurs. It should be noted that if the DC resistance and insulation resistance of the solenoid valve do not decrease significantly within the test time, the acceptable test time is used to calculate the lifespan of the solenoid valve coil. This acceptable test time is determined based on the inherent characteristics of the solenoid valve itself.

[0078] The coil's lifespan assessment model is as follows:

[0079]

[0080] (1) In the formula, T a and T b τa refers to the material's intrinsic temperature during operation, measured in °C. τb refers to the material's lifespan at temperature Ta, and τa refers to the material's lifespan at temperature Tb. In this experiment, Ta refers to the temperature of the coil insulation system of the unaged sample under operating temperature and excitation conditions, i.e., the initial excitation temperature. Tb refers to the temperature of the sample insulation system after aging was terminated under the test temperature and excitation conditions at 100 °C, i.e., the aging excitation temperature.

[0081] Step S103: Perform compression deformation and aging tests on the rubber seals, and determine the lifespan of the rubber seals based on the test results.

[0082] In this embodiment of the invention, performing compression deformation and aging tests on the rubber seal and determining the lifespan of the rubber seal based on the test results includes: obtaining the initial height of the rubber seal; conducting an aging test on the rubber seal and obtaining the aging height of the rubber seal after aging, and recording the aging test temperature of the rubber seal during the aging process; the aging height is the height of the rubber seal after completing the aging test; determining the evaluation parameters and failure criteria of the rubber seal; the evaluation parameter is the permanent compression deformation; after determining the evaluation parameters, calculating the test compression ratio of the rubber seal based on the initial height and the aging height, or determining the test compression ratio of the rubber seal based on a reference standard; determining the critical time based on the test compression ratio and the failure criteria; and calculating the lifespan of the rubber seal based on the critical time and the aging test temperature.

[0083] In this embodiment of the invention, obtaining the initial height of the rubber seal includes: placing the rubber seal in a compression clamp; allowing it to stand for a first preset time under standard test conditions; opening the compression clamp and allowing it to stand for a second preset time, and measuring the current height of the rubber seal; the current height is the initial height of the rubber seal. Optionally, both the first preset time and the second preset time can be set to 1 day. Of course, in some other embodiments, the first preset time and the second preset time can be adjusted according to actual needs.

[0084] In this embodiment of the invention, the aging test on the rubber seal and the determination of the aging height of the rubber seal after aging include: placing the rubber seal in a compression set fixture; placing the entire compression set fixture into an aging chamber for aging; after the aging time is reached, removing the compression set fixture from the aging chamber and taking the rubber seal out of the compression set fixture; and measuring the height of the rubber seal after a preset time period to obtain the aging height of the rubber seal. The preset time period can be half an hour. Of course, in some other embodiments, the preset time period can be adjusted according to actual needs.

[0085] Specifically, such as Figure 4 As shown, the initial compression sample height of the rubber seal is first tested. The rubber seal is placed in a compression fixture and left to stand for one day under standard test conditions. Then, the compression fixture is opened, and the seal is left to stand for another day before the initial height is measured. Next, an aging test is performed. The rubber seal is placed in a compression set fixture, and then the entire fixture is placed in an aging chamber for aging. The aging test can be conducted in an aging chamber according to "3512-2014 Accelerated Aging and Heat Resistance Test of Vulcanized Rubber or Thermoplastic Rubber in Hot Air". At the sampling time, the compression set fixture is removed from the aging chamber, and after the fixture is removed, the seal is left to stand for half an hour before its height is measured again; this is the aging height. By measuring the initial height and the aging height, the compression set rate of the rubber seal can be calculated.

[0086] Furthermore, before conducting a life assessment, it is necessary to determine the evaluation parameters and failure criteria.

[0087] Specifically, compression set and elongation at break are two of the most commonly used performance parameters for predicting the service life of rubber materials. Since the sealing function of solenoid valve rubber seals is achieved by generating strong elastic stress through compression to prevent gas or liquid leakage in the confined space, compression set is more closely approximating the actual service condition of the seal ring. Therefore, using compression set as an evaluation parameter is more appropriate. In this embodiment of the invention, according to the "Rapid Prediction Method for the Service Life of Static Sealing Rubber Products," a compression set threshold of 50% is selected as the failure criterion.

[0088] The aging test conditions are as follows: There are generally three aging test temperatures, with an interval of at least 5 percentage points between adjacent temperatures. The compression set rate can be calculated based on the aging height and initial height measured at different temperatures. The compression set rate can be calculated using the compression set calculation formula in "Determination of Compression Set of Vulcanized or Thermoplastic Rubber - Part 1: Under Normal and High Temperature Conditions". Alternatively, when the actual compression set of the rubber seal cannot be measured, it can be recommended according to "Determination of Compression Set of Vulcanized or Thermoplastic Rubber - Part 1: Under Normal and High Temperature Conditions": a compression set of 25% for rubber with an international hardness of 10–80; and 15% and 10% for rubber with an international hardness greater than 80, specifically 81–89 and 90–95, respectively.

[0089] Specifically, index tests are conducted during the aging test. At three different accelerated aging temperatures, the compression set (i.e., test compression ratio) of the rubber seal is measured every 72 hours thereafter after 24h, 48h, 96h, and 168h. The test ends when the compression set reaches 50%, and the test time is recorded. The evaluation result, i.e., the life of the rubber seal, is obtained by using the standard calculation model "Arrhenius plot for calculating life and maximum service temperature of vulcanized or thermoplastic rubber" through a two-step linear fitting.

[0090] Step S104: Perform stress relaxation tests on the spring and determine the life of the spring based on the test results.

[0091] In this embodiment of the invention, performing stress relaxation tests on the spring and determining the spring's lifespan based on the test results includes: using a dual-thread single-cycle loading scheme to compress the spring to a target deformation amount and holding it for a fourth preset time; performing a heating test on the spring and holding it at a target temperature for a fifth preset time; repeating the heating test and recording multiple temperature data points of the spring at the target deformation amount; determining multiple load decay curves of the spring based on the multiple temperature data points and the target deformation amount; and calculating the spring's lifespan based on the multiple load decay curves. Optionally, the fourth preset time can be 10 hours, and the fifth preset time can be 30 minutes. Of course, in other embodiments, the fourth and fifth preset times can be adjusted according to actual needs.

[0092] Specifically, based on the structural characteristics of the solenoid valve helical spring and the technical requirements of high-temperature stress relaxation testing, this invention requires the design of a continuous spring stress relaxation testing system (including a high-temperature furnace, spring clamps, push-pull force sensors, data acquisition cards, and a computer). The specific experiments and tests are as follows:

[0093] Step 1: Employ a dual-thread single-cycle loading scheme. First, use force loading control to apply the load required for the target deformation; then, use displacement control to ensure the spring is compressed to the target deformation (wherein, the target deformation is the deformation of the solenoid valve under normal operating conditions), and then maintain the load for 10 hours.

[0094] Step 2: Clamp the spring with spring clamps and place it into the high-temperature furnace. Then move the middle crossbeam to the appropriate position (subject to actual testing). After assembly, turn off the high-temperature furnace.

[0095] Step 3: Next, slowly heat the high-temperature furnace to the target temperature over 30 minutes, and then keep it at that temperature for another 30 minutes to ensure that the spring is fully heated.

[0096] Step 4: Record the data of the spring at the target deformation and corresponding temperature to form the spring load decay curve and determine the load decay of the spring after 10 hours.

[0097] Step 5: After completing the test at this temperature, adjust the temperature of the high-temperature furnace and conduct the next test, that is, repeat steps 3 to 4 to obtain test data of spring stress relaxation test at multiple high temperatures (usually about 5), that is, multiple sets of spring load attenuation curves and corresponding load attenuation amounts.

[0098] Step 6: Calculate the spring life based on the multiple sets of spring load decay curves and corresponding load decay amounts obtained above. The specific calculation of spring life is as follows:

[0099] The continuous stress relaxation method is the main method for measuring stress relaxation in springs. Using a dynamic stress relaxation testing device, stress relaxation tests are conducted on springs at a series of different temperatures to obtain the relationship between temperature and the spring load attenuation rate.

[0100] ΔP / P=A+Blnt (2);

[0101] (2) In the formula, ΔP = P - P t P is the initial load before the spring load decays. t The load ΔP / P is the real-time load during the stress relaxation test; therefore, ΔP / P is called the load attenuation rate. t is the relaxation time, and A and B are temperature-dependent parameters. Numerous studies have shown that the load attenuation rate ΔP / P in spring stress relaxation problems exhibits a bilinear relationship with the natural logarithm of the relaxation time, lnt.

[0102] Furthermore, since the stress relaxation process can be considered as a thermal activation process of dislocations, the relaxation rate V s The relationship between absolute temperature T and the activation energy Q required for dislocations to pass through the barrier conforms to the Arrhenius equation:

[0103]

[0104] (3) In the formula, V s The relaxation rate is defined in this problem as... Q is the activation energy required for a dislocation to overcome a barrier under a certain stress. γ is a constant, and k is the Boltzmann constant (8.6 × 10⁻⁶). ―5 eV / K), where T is the absolute temperature (K).

[0105] Taking the natural logarithm of both sides of equation (3), we get:

[0106]

[0107] Therefore In a coordinate system, the logarithm of the relaxation rate is linearly related to the reciprocal of the absolute temperature. Let the slope of this line be m, then we have:

[0108]

[0109] Right now:

[0110] Q = -m × k (6);

[0111] Therefore, by determining the stress relaxation rate at different temperatures, the activation energy Q can be calculated using equation (6). Comparing the stress relaxation rate at a higher test temperature (T1) with the stress relaxation rate under the normal operating temperature condition (T0) of the spring, we can obtain:

[0112]

[0113] Therefore, the stress relaxation rate under the operating temperature T0 can be obtained:

[0114]

[0115] The result of The value is the coefficient in the stress relaxation stage II equation (2) at the operating temperature.

[0116] Furthermore, if the relaxation time t = 1h is substituted into equation (2), we can obtain:

[0117]

[0118] Therefore, the coefficient A in the relaxation equation ΔP / P=A+Blnt can be understood as the load attenuation rate after the spring stress relaxes for 1 hour. According to equation (3), we can obtain:

[0119]

[0120] Taking the natural logarithm of both sides of equation (9), we get:

[0121]

[0122] According to equation (11), lnA and The linear relationship can determine the equation for the relaxation stage II at the spring operating temperature.

[0123] Finally, by using the obtained activation energy to obtain the coefficients in the relaxation equation at the operating temperature, the life of the spring at the normal operating temperature of the solenoid valve can be predicted through stress relaxation tests at a series of temperatures.

[0124] Step S105: Predict the lifespan of the solenoid valve based on the lifespan of the coil, the rubber seal, and the spring.

[0125] In this embodiment of the invention, predicting the lifespan of the solenoid valve based on the lifespan of the coil, the rubber seal, and the spring includes: comparing the lifespans of the coil, the rubber seal, and the spring to determine the minimum lifespan; and predicting the lifespan of the solenoid valve based on the minimum lifespan. That is, the lifespan of the component with the shortest lifespan among the coil, the rubber seal, and the spring is the lifespan of the solenoid valve.

[0126] It should be noted that the aforementioned steps S102, S103, and S104 are not required to be executed in any particular order; they can be executed sequentially or in parallel. This invention does not impose any specific limitations.

[0127] refer to Figure 5 The present invention also provides a life prediction device for a solenoid valve.

[0128] like Figure 5 As shown, the life prediction device for the solenoid valve includes:

[0129] The critical component identification unit 501 is used to identify the critical components of the solenoid valve; the critical components include: coil, rubber seal and spring;

[0130] The coil life analysis unit 502 is used to perform aging tests and analyses on the coil and determine the coil life based on the analysis results.

[0131] The rubber seal analysis unit 503 is used to perform compression deformation and aging tests on the rubber seal and determine the life of the rubber seal based on the test results.

[0132] The spring life analysis unit 504 is used to perform stress relaxation tests and assessments on the spring and determine the spring life based on the test results.

[0133] The life prediction unit 505 is used to predict the life of the solenoid valve based on the life of the coil, the life of the rubber seal, and the life of the spring.

[0134] Specifically, the specific operational process of the various units in the solenoid valve life prediction device can be referred to the solenoid valve life prediction method mentioned above, and will not be repeated here.

[0135] The solenoid valve life prediction method of this invention can effectively assess the effective service life of solenoid valves that are normally demagnetized or excited, solving the problem of inaccurate life assessment of solenoid valve operation counts for normally demagnetized or excited solenoid valves in current market methods. This improves the accuracy of life prediction for normally demagnetized or excited solenoid valves in industrial production processes, enhances equipment management for this type of solenoid valve in factories, enables the development of appropriate maintenance strategies, and improves the economy and safety of factory production.

[0136] For example, nuclear power plants use a large number of solenoid valves in their protective actuators. These solenoid valves are constantly in an energized or de-energized state, only activating to perform protective actions after a protection signal is triggered. The function of these solenoid valves directly impacts nuclear safety and power plant production. Repairing or replacing them only after a failure is unacceptable; a preventative maintenance and replacement strategy must be developed. This requires a high degree of accuracy in the replacement cycle. Current methods for predicting solenoid valve lifespan based on the number of actuations clearly do not match the actual lifespan of solenoid valves used in the field. The solenoid valve lifespan prediction method of this invention can effectively predict the lifespan of solenoid valves under static operating conditions due to factors such as coil insulation degradation, permanent compression deformation of seals, and spring stress relaxation. This allows for accurate prediction of the solenoid valve's service life under static conditions. This technology has been successfully applied to the turbine trip protection solenoid valve in a domestic nuclear power plant, accurately predicting the effective service life of the trip solenoid valve. The prediction results show a high degree of fit with the actual service life in the field, providing strong support for the formulation of turbine trip solenoid valve replacement cycles.

[0137] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0138] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0139] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0140] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They do not limit the scope of protection of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A method for predicting the lifespan of a solenoid valve, applied to a normally energized solenoid valve or a de-energized solenoid valve, characterized in that, Includes the following steps: Identify the key components of the solenoid valve; these key components include: coil, rubber seal, and spring. An aging test and analysis of the coil are performed, and the lifespan of the coil is determined based on the analysis results. This process includes: performing a magnetic flux density test on the coil; collecting initial data of the coil after the magnetic flux density test; conducting a high-low temperature alternating aging test on the coil; collecting aging data of the coil during the aging test; and evaluating the lifespan of the coil based on the initial data and the aging data to obtain the coil's lifespan. Perform compression deformation and aging tests on the rubber seal, and determine the life of the rubber seal based on the test results; Perform stress relaxation tests on the spring and determine the life of the spring based on the test results; The lifespan of the solenoid valve is predicted based on the lifespan of the coil, the lifespan of the rubber seal, and the lifespan of the spring. The initial data includes: initial DC resistance, initial insulation resistance, and initial excitation temperature; The aging data includes: aging DC resistance, aging insulation resistance, and temperature during aging excitation. The step of evaluating the lifespan of the coil based on the initial data and the aging data to obtain the lifespan of the coil includes: determining the critical value of the coil aging state based on the initial DC resistance, the initial insulation resistance, the aging DC resistance, and the aging insulation resistance; determining the test time based on the critical value of the aging state; and calculating the lifespan of the coil based on the initial excitation temperature, the aging excitation temperature, and the test time.

2. The life prediction method for a solenoid valve according to claim 1, characterized in that, The key components of the solenoid valve include: Obtain the component information and structural information of the solenoid valve; The key components are determined based on the component information and the structural information.

3. The life prediction method for a solenoid valve according to claim 1, characterized in that, The process of performing compression deformation and aging tests on the rubber seal and determining the lifespan of the rubber seal based on the test results includes: Obtain the initial height of the rubber seal; An aging test is performed on the rubber seal, and the aging height of the rubber seal is obtained after aging is completed. The aging test temperature of the rubber seal is also recorded during the aging process. The aging height is the height of the rubber seal after the aging test is completed. Determine the evaluation parameters and failure criteria for the rubber seal; the evaluation parameter is the compression set. After determining the evaluation parameters, the test compression ratio of the rubber seal is calculated based on the initial height and the aging height, or the test compression ratio of the rubber seal is determined based on a reference standard. The critical time is determined based on the experimental compression ratio and the failure criterion. The lifespan of the rubber seal is calculated based on the critical time and the aging test temperature.

4. The life prediction method for a solenoid valve according to claim 3, characterized in that, The process of obtaining the initial height of the rubber seal includes: Place the rubber seal in the compression clamp; Under standard test conditions, allow to stand for the first preset time; After opening the compression clamp, let it stand for a second preset time, and measure the current height of the rubber seal; the current height is the initial height of the rubber seal.

5. The life prediction method for a solenoid valve according to claim 3, characterized in that, The step of conducting an aging test on the rubber seal and obtaining the aging height of the rubber seal after aging includes: The rubber seal is placed in a compression set fixture; The entire compression set fixture was placed in an aging chamber for aging. After the aging time is reached, the compression set fixture is removed from the aging chamber, and the rubber seal is removed from the compression set fixture. After a preset time period, the height of the rubber seal is measured to obtain the aging height of the rubber seal.

6. The life prediction method for a solenoid valve according to claim 1, characterized in that, The process of performing stress relaxation tests on the spring and determining the lifespan of the spring based on the test results includes: A dual-threaded single-loop loading scheme is used to compress the spring, so that the spring is compressed to the target deformation amount and then held for a fourth preset time. Perform a heating test on the spring, and hold the spring at the target temperature for a fifth preset time; Repeat the heating test described above and record multiple temperature data of the spring under the target deformation. Multiple load decay curves of the spring are determined based on the multiple temperature data and the target deformation. The lifespan of the spring is calculated based on the multiple load attenuation curves.

7. The life prediction method for a solenoid valve according to claim 1, characterized in that, Predicting the lifespan of the solenoid valve based on the lifespan of the coil, the lifespan of the rubber seal, and the lifespan of the spring includes: The lifespan of the coil, the lifespan of the rubber seal, and the lifespan of the spring are compared to determine the minimum lifespan. The lifespan of the solenoid valve is predicted based on the minimum value of the lifespan.

8. A life prediction device for a solenoid valve, characterized in that, include: Key component identification unit, used to identify the key components of the solenoid valve; The key components include: coil, rubber seal, and spring; A coil life analysis unit is used to perform aging tests and analyses on the coil, and determine the coil's lifespan based on the analysis results. The process of performing aging tests and analyses on the coil and determining the coil's lifespan based on the analysis results includes: performing a magnetic induction intensity test on the coil; collecting initial data of the coil after completing the magnetic induction intensity test; performing a high-low temperature alternating aging test on the coil; collecting aging data of the coil during the aging test; and evaluating the coil's lifespan based on the initial data and the aging data to obtain the coil's lifespan. A rubber seal analysis unit is used to perform compression deformation and aging tests on the rubber seal and determine the life of the rubber seal based on the test results. The spring life analysis unit is used to perform stress relaxation tests and assessments on the spring, and determine the life of the spring based on the test results. A life prediction unit is used to predict the life of the solenoid valve based on the life of the coil, the life of the rubber seal, and the life of the spring. The initial data includes: initial DC resistance, initial insulation resistance, and initial excitation temperature; The aging data includes: aging DC resistance, aging insulation resistance, and temperature during aging excitation. The step of evaluating the lifespan of the coil based on the initial data and the aging data to obtain the lifespan of the coil includes: determining the critical value of the coil aging state based on the initial DC resistance, the initial insulation resistance, the aging DC resistance, and the aging insulation resistance; determining the test time based on the critical value of the aging state; and calculating the lifespan of the coil based on the initial excitation temperature, the aging excitation temperature, and the test time.

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