Aviation rubber static seal ring service life prediction method based on temperature analysis

Abstract

The invention belongs to the technical field of static sealing elements, and relates to a temperature analysis-based aviation rubber static sealing ring service life prediction method, which comprises the following steps: S1, carrying out an aging temperature test on an aviation rubber static sealing ring to obtain performance parameters; s2, establishing a dynamic curve performance degradation model of the aviation rubber static sealing ring, and estimating aging parameters, test parameters and aging rate parameters; s3, determining the working state of the aviation rubber static sealing ring according to the deformation rate of the aviation rubber static sealing ring; and S4, establishing an aging prediction model of the aviation rubber static sealing ring under the target working condition, and obtaining a life prediction result. According to the static seal life prediction method based on the temperature influence, the extreme high-temperature condition is injected into the dynamic curve performance degradation model, the obtained aging prediction model is high in accuracy, the test period is effectively shortened through the high-temperature acceleration test, the aging data of the seal ring can be obtained in a short time, and the method is suitable for popularization and application. The method has positive effects on product design, material optimization and process improvement.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber seal test, and in particular relates to a method for predicting the life of an aviation rubber static seal ring based on temperature analysis. Background Art

[0002] Rubber sealing rings are widely used in the field of aviation equipment due to their simple structure. However, due to the structural characteristics of the molecular chain of the rubber material itself and the influence of external environment such as temperature, humidity, oxygen, etc. during storage, they will slowly age, resulting in a decrease in their sealing performance and even causing equipment failure.

[0003] The main method for predicting the life of sealing rings is the Arrhenius model. This method is based on the relationship between chemical reaction rate and temperature. It assumes that the aging of sealing rings is mainly driven by temperature. According to the life test data at different aging temperatures, the Arrhenius model is established to estimate the aging life at the target temperature. However, this type of method only reflects the simple correspondence between the life and the test temperature value, and cannot fully consider the impact of other key factors on the life, and cannot dynamically reflect the changing trends of performance parameters such as aging deformation and stress relaxation during the test.

[0004] To solve the above problems, the present invention proposes a static seal life prediction and evaluation method taking into account the influence of temperature. By performing multiple groups of accelerated aging tests on the sealing ring at different temperatures, the Arrhenius model is improved to make the relationship between the reaction temperature and the aging rate parameter, which is injected into the kinetic curve performance degradation model. Combined with the modified kinetic model, the sealing ring life at the target temperature is predicted by extrapolation. The experimental results are compared with the predicted results of the sealing ring to evaluate the accuracy of the life prediction. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a life prediction method for aviation rubber static sealing rings based on temperature analysis. By injecting extreme high temperature conditions into the dynamic curve performance degradation model, the obtained aging prediction model has high accuracy. Through high temperature accelerated testing, the test cycle is effectively shortened, and the sealing ring aging data can be obtained in a relatively short time, which is of great significance for product design, material optimization and process improvement.

[0006] To achieve the above object, the present invention discloses the following technical solution:

[0007] A method for predicting the life of an aviation rubber static seal ring based on temperature analysis, comprising:

[0008] S1: Perform an aging temperature test on the aviation rubber static seal ring to obtain the performance parameters of the aviation rubber static seal ring;

[0009] Set the aging temperature and test time of the aviation rubber static seal ring for the aging temperature test, and obtain the temperature, time and performance parameters of the aviation rubber static seal ring;

[0010] S2: Establish the dynamic curve performance degradation model of aviation rubber static seal ring, and estimate the aging parameters, test parameters and aging rate parameters by successive approximation method and least square method;

[0011] S21: establishing a dynamic curve performance degradation model of the aviation rubber static seal ring according to the temperature, time and performance parameters of the aviation rubber static seal ring in step S1, and predicting the aging degree of the aviation rubber static seal ring;

[0012] S22: Estimate the aging parameter α of the aviation rubber static seal ring by the successive approximation method, specifically:

[0013]

[0014] in, is the predicted value of the compression set retention rate of the jth aviation rubber static seal ring; It is the experimental value of compression permanent deformation retention rate of aviation rubber static seal ring; is the predicted value of the test parameter of a single group; is the predicted value of a single group of aging rate parameters; α is the aging parameter of the aviation rubber static seal ring, 0<α<1; min I is the minimization objective function value; is the test time after data processing; i1 is the test temperature stress group ordinal number; j is the test time group ordinal number; n1 is the total number of test temperature stress groups; n2 is the total number of test time groups; e is a natural constant;

[0015] S23: Take the natural logarithm of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring in step S21, convert the dynamic curve into a straight line, analyze the regression parameters by the least squares method, and obtain the test parameter B and aging rate parameter K of the aviation rubber static seal ring:

[0016]

[0017] Among them, K is the aging rate parameter of the aviation rubber static seal ring; B is the test parameter of the aviation rubber static seal ring; n is the number of samples in the performance degradation test; i is the sample ordinal number in the performance degradation test; b is the first parameter of the linear regression model; x i is the test time after data processing, y i is the deformation rate of the sealing ring after data processing, y i =ln(1-ε i ); is the average product of the test time and the sealing ring deformation rate after data processing, is the average value of the test time after data processing, is the average value of the sealing ring deformation rate after data processing, a is the second parameter of the linear regression model;

[0018] S24: Establish the Arrhenius model of the aviation rubber static seal ring to predict the aging rate parameters at the target temperature; take the natural logarithm of both ends of the Arrhenius model of the aviation rubber static seal ring, perform regression parameter analysis by the least squares method, and then determine the predicted value of the aging rate parameter and the predicted values ​​of the test parameters

[0019] S3: Determine the working state of the aviation rubber static seal ring according to the deformation rate of the aviation rubber static seal ring; the sealing state judgment standard of the aviation rubber static seal ring based on the demand threshold is:

[0020]

[0021] Among them, ε0 is the judgment threshold of the sealing demand of the aviation rubber ring; ε i S is the deformation rate of aviation rubber static seal ring; i Represents the working state of the rubber ring, S i =1 is the normal sealing state, S i =0 means sealing failure state;

[0022] When the sealing state of the aviation rubber static seal ring is judged to be a normal sealing state S i =1, then execute step S4 to perform life prediction;

[0023] When the sealing state of the aviation rubber static seal ring is judged as a sealing failure state S i =0, then step S4 is not executed, indicating that the seal fails and a new aviation rubber static seal ring is replaced;

[0024] S4: Establish an aging prediction model for the aviation rubber static seal ring under the target working condition. The life prediction result of the aviation rubber static seal ring is:

[0025]

[0026] Among them, t is the life prediction result of aviation rubber static seal ring; is the predicted value of the aging rate parameter at the target temperature; is the predicted value of the test parameters at the target temperature.

[0027] Preferably, the requirements for obtaining the temperature, time and performance parameters of the aviation rubber static seal ring in step S1 are specifically:

[0028] The performance parameter of the aviation rubber static seal ring requires that the compression permanent deformation at each set test temperature is less than or equal to 20%;

[0029] Four detection points are evenly set on the radial and axial circumferences of the aviation rubber static seal ring, and their cross-sectional diameters are measured, and their arithmetic mean is taken as the detection result of the deformation of the aviation rubber static seal ring; the assembly of the aviation rubber static seal ring is taken out according to the set test time, cooled at room temperature for 1 hour, and then the assembly is opened, and the aviation rubber static seal ring is cooled and restored for 24 hours, and the cross-sectional heights of the four evenly distributed points on each seal ring are measured respectively, and the arithmetic mean is taken, and the initial value and the end value of the performance parameter are recorded.

[0030] Preferably, the dynamic curve performance degradation model of the aviation rubber static seal ring in step S21 is specifically:

[0031] Taking compression permanent deformation as the performance degradation parameter of aviation rubber static seal ring, a performance degradation trajectory model of compression permanent deformation and service time is established under each test temperature stress. The static seal ring aging prediction model obtained is:

[0032]

[0033] Among them, C is the compression permanent deformation degree of the aviation rubber static seal ring; h0 is the original cross-sectional diameter of the seal ring; h1 is the height of the seal groove of the test fixture; and h2 is the radial cross-sectional height of the seal ring after deformation.

[0034] Preferably, the predicted value of the single group test parameter in step S22 is for:

[0035]

[0036] in, is the predicted value of the second parameter of the linear regression model; is the predicted value of the first parameter of the linear regression model.

[0037] Preferably, the predicted value of the single group test parameter in step S22 is for:

[0038]

[0039] in, is the predicted value of the second parameter of the linear regression model.

[0040] Preferably, in step S23, the natural logarithms of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring are taken, the dynamic curve is converted into a straight line, and the regression parameters are analyzed by the least squares method, specifically:

[0041] Taking the natural logarithm of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring, the aging model of the aviation rubber static seal ring is obtained as follows:

[0042] ln(1-C)=lnB-Kt α

[0043] Let a = ln(B), b = -K, x = t α , y = ln(1-C), and the linear regression model of the aviation rubber static seal ring is obtained as follows:

[0044] y=a+b·x

[0045] The least squares method is used to analyze the regression fitting, and the linear regression model parameters are obtained as follows:

[0046]

[0047] Preferably, in step S24, the natural logarithms of both ends of the Arrhenius model of the aviation rubber static seal ring are taken, and regression parameter analysis is performed by the least squares method, specifically:

[0048] Aging rate parameter K at target temperature t The Arrhenius model that conforms to the thermodynamic temperature T is:

[0049]

[0050] Where A is the frequency factor; T is the thermodynamic target temperature of the aging test; E is the apparent activation energy; K t is the aging rate parameter at the target temperature; R is the activation energy of the failure mechanism;

[0051] By solving the aging rate parameter K at the target temperature t The relationship between the thermodynamic temperature T can be used to derive the aging rate parameter K at the target temperature. t The value of the Arrhenius model is taken as the natural logarithm of the parameters at both ends, and z=ln(K i ), c = ln(A), Establish the aging rate parameter K at the target temperature t The linear regression model between and thermodynamic temperature T is:

[0052] z=d+ck

[0053] Where k is the test temperature after data processing, z is the aging rate parameter after data processing, z = ln(K i );d is the first parameter of the Arrhenius linear regression model;c is the second parameter of the Arrhenius linear regression model;

[0054] The least squares method is used to analyze the regression fitting, and the linear regression model parameters are obtained as follows:

[0055]

[0056] Wherein, m is the number of temperature groups in the performance degradation test; i2 is the temperature sequence number in the performance degradation test; is the average product of the test temperature and aging rate parameter after data processing, is the average value of the test temperature after data processing; is the average value of the aging rate parameter after data processing,

[0057] Preferably, the predicted value of the test parameter at the target temperature in step S4 is for:

[0058]

[0059] in, is the predicted value of the test parameters at the target temperature.

[0060] Preferably, the predicted value of the aging rate parameter at the target temperature in step S4 is for:

[0061]

[0062] in, is the predicted value of the aging rate parameter at the target temperature.

[0063] Compared with the prior art, the present invention has the following beneficial effects:

[0064] (1) The present invention injects Arrhenius extreme high temperature conditions into the kinetic curve performance degradation model to establish an aging prediction model, which reflects the aging process data and realizes the life prediction of the static seal ring. In addition, through high temperature accelerated testing, the test cycle is effectively shortened, and important data on the aging of the seal ring can be obtained in a relatively short time, which is of great significance for guiding product design, optimizing material selection and improving processes.

[0065] (2) The aging prediction model established by the accelerated life prediction method for aviation static seal rings considering the temperature effect proposed in the present invention has a high accuracy rate and can accurately complete the life prediction of aviation static seal rings within an acceptable error range. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a control block diagram of the aviation rubber static seal ring life prediction method based on temperature analysis of the present invention;

[0067] Figure 2 This is a flow chart of the static seal aging temperature test of the present invention;

[0068] Figure 3 A schematic diagram of the structure of a nitrile rubber sealing ring in a preferred embodiment of the present invention;

[0069] Figure 4 It is a performance degradation curve diagram at different temperatures of the present invention;

[0070] Figure 5 This is a diagram showing the verification effect of the aging prediction model of the present invention. DETAILED DESCRIPTION

[0071] The exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0072] The embodiment of the present invention takes the compression state of a nitrile rubber sealing ring in jet fuel oil as a specific analysis case, and provides a method for predicting the life of an aviation rubber static sealing ring based on temperature analysis, such as Figure 1 As shown, an aging temperature test is performed on the aviation rubber static seal ring to obtain performance parameters; a dynamic curve performance degradation model of the aviation rubber static seal ring is established, and the aging parameters, test parameters and aging rate parameters are estimated; the working state of the aviation rubber static seal ring is determined according to the deformation rate of the aviation rubber static seal ring; an aging prediction model of the aviation rubber static seal ring under the target working condition is established to obtain the life prediction result; it includes:

[0073] Step S1: Perform an aging temperature test on the aviation rubber static seal ring to obtain performance parameters of the aviation rubber static seal ring.

[0074] like Figure 2The flowchart of the static seal aging temperature test of the present invention is shown; the aging temperature and test time of the aviation rubber static seal ring for the aging temperature test are set, and the temperature, time and performance parameters of the aviation rubber static seal ring are obtained, specifically: the performance parameter of the aviation rubber static seal ring requires that the compression permanent deformation at each set test temperature is less than or equal to 20%; 4 detection points are evenly set on the radial and axial circumferences of the aviation rubber static seal ring, and the cross-sectional diameters are measured, and the arithmetic mean is taken as the detection result of the deformation of the aviation rubber static seal ring; the assembly of the aviation rubber static seal ring is taken out according to the set test time, cooled at room temperature for 1 hour, and then the assembly is opened, and the aviation rubber static seal ring is cooled and restored for 24 hours, and the cross-sectional heights of the 4 evenly distributed points on each seal ring are measured respectively, and the arithmetic mean is taken, and the initial value and the end value of the performance parameter are recorded.

[0075] Step S2: Establish a dynamic curve performance degradation model for the aviation rubber static seal ring, and estimate the aging parameters, test parameters and aging rate parameters by successive approximation method and least square method.

[0076] Step S21: According to the temperature, time and performance parameters of the aviation rubber static seal ring in step S1, a dynamic curve performance degradation model of the aviation rubber static seal ring is established to predict the aging degree of the aviation rubber static seal ring, specifically:

[0077] Taking compression permanent deformation as the performance degradation parameter of aviation rubber static seal ring, a performance degradation trajectory model of compression permanent deformation and service time is established under each test temperature stress. The static seal ring aging prediction model obtained is:

[0078]

[0079] Among them, C is the compression permanent deformation degree of the aviation rubber static seal ring; h0 is the original cross-sectional diameter of the seal ring; h1 is the height of the seal groove of the test fixture; and h2 is the radial cross-sectional height of the seal ring after deformation.

[0080] The present invention takes the compressed state of nitrile rubber 5080 in jet fuel oil as an example. Figure 3 The structure diagram of the nitrile rubber sealing ring of the present invention is shown; an aging prediction model is established to predict the product life, verify the accelerated life prediction evaluation and failure consistency test. To simplify the calculation, the present invention selects 3 groups of sealing ring aging tests at different temperatures (50, 100, 130°C) and a group of high temperature (150°C) life verification tests. The experimental data are shown in Table 1.

[0081] Table 1 Compression set values ​​of high temperature accelerated aging test

[0082]

[0083]

[0084] Step S22: Estimate the aging parameter α of the aviation rubber static seal ring by successive approximation method, specifically:

[0085]

[0086] in, is the predicted value of the compression set retention rate of the jth aviation rubber static seal ring; It is the experimental value of compression permanent deformation retention rate of aviation rubber static seal ring; is the predicted value of the test parameter of a single group; is the predicted value of a single group of aging rate parameters; α is the aging parameter of the aviation rubber static seal ring, 0<α<1; min I is the minimization objective function value; is the test time after data processing; i1 is the test temperature stress group ordinal number; j is the test time group ordinal number; n1 is the total number of test temperature stress groups; n2 is the total number of test time groups; e is a natural constant;.

[0087] The aging constant α of this type of material is estimated using the successive approximation method. The calculation results are shown in Table 2:

[0088] Table 2 The sum of squares of deviations when different aging constants α are selected

[0089] α 0.46 0.47 0.48 0.49 0.500 I 0.1488771 0.1420603 0.1391104 0.1403987 0.1463061

[0090] From the above data, we can get that when the aging constant α is selected as 0.48, the sum of squares of the deviations between the predicted values ​​and the experimental values ​​of the three groups of experiments is the smallest, indicating that when α = 0.48 is selected for the nitrile rubber sealing ring under the working condition of jet fuel oil, the aging prediction model has the best fitting degree. Table 3 shows the aging prediction model parameters, which are the prediction model parameter values ​​at the three groups of temperatures.

[0091] Table 3 Parameters of aging prediction model

[0092] Temperature / ℃ 50 100 130 K 0.00172 0.0220 0.0684 B 0.9623 1.0387 1.1264 r 0.9686 0.9013 0.9754

[0093] Predicted values ​​of single test parameters for:

[0094]

[0095] in, is the predicted value of the second parameter of the linear regression model; is the predicted value of the first parameter of the linear regression model.

[0096] Predicted values ​​of single test parameters for:

[0097]

[0098] in, is the predicted value of the second parameter of the linear regression model.

[0099] Step S23: Take the natural logarithm of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring in step S21, convert the dynamic curve into a straight line, and analyze the regression parameters by the least squares method, specifically:

[0100] Taking the natural logarithm of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring, the aging model of the aviation rubber static seal ring is obtained as follows:

[0101] ln(1-C)=lnB-Kt α ;

[0102] Let a = ln(B), b = -K, x = t α , y = ln(1-C), and the linear regression model of the aviation rubber static seal ring is obtained as follows:

[0103] y = a + b x;

[0104] The least squares method is used to analyze the regression fitting, and the linear regression model parameters are obtained as follows:

[0105]

[0106] The test parameter B and aging rate parameter K of the aviation rubber static seal ring are obtained as follows:

[0107]

[0108] Among them, K is the aging rate parameter of the aviation rubber static seal ring; B is the test parameter of the aviation rubber static seal ring; n is the number of samples in the performance degradation test; i is the sample ordinal number in the performance degradation test; b is the first parameter of the linear regression model; χ i is the test time after data processing, y i is the deformation rate of the sealing ring after data processing, y i =ln(1-ε i ); is the average product of the test time and the sealing ring deformation rate after data processing, is the average value of the test time after data processing, is the average value of the sealing ring deformation rate after data processing, a is the second parameter of the linear regression model.

[0109] like Figure 4 The performance degradation curves of the present invention at different temperatures are shown; the aging prediction model at different temperatures is obtained according to the calculated aging rate constant K and test constant B at each temperature, and the model is as follows:

[0110] 50℃: 1-ε=0.9623e -0.00172t0.48 ;

[0111] 100℃:

[0112] 130℃:

[0113] The Arrhenius model was established based on the aging rates of three different tests. The natural logarithms on both sides of the equation were removed, and the curve was converted into a straight line. The aging rate constant K at 150°C was calculated by linear regression simulation using the least squares method. The intercept of the linear regression equation parameters is a=12.2823; the slope is b=-6.0218; and the correlation coefficient is r=0.9998, indicating that the fitting effect is very good.

[0114] Step S24: Establishing the Arrhenius model of the aviation rubber static seal ring to predict the aging rate parameters at the target temperature; taking the natural logarithm of both ends of the Arrhenius model of the aviation rubber static seal ring, performing regression parameter analysis by the least squares method, and then determining the predicted value of the aging rate parameter and the predicted values ​​of the test parameters Specifically:

[0115] Aging rate parameter K at target temperature t The Arrhenius model that conforms to the thermodynamic temperature T is:

[0116]

[0117] Where A is the frequency factor; T is the thermodynamic target temperature of the aging test; E is the apparent activation energy; K t is the aging rate parameter at the target temperature; R is the activation energy of the failure mechanism.

[0118] By solving the aging rate parameter K at the target temperature t The relationship between the thermodynamic temperature T can be used to derive the aging rate parameter K at the target temperature. t The value of the Arrhenius model is taken as the natural logarithm of the parameters at both ends, and z=ln(K i ), c = ln(A), Establish the aging rate parameter K at the target temperature t The linear regression model between and thermodynamic temperature T is:

[0119] z=d+ck;

[0120] Where k is the test temperature after data processing, z is the aging rate parameter after data processing, z = ln(K i );d is the first parameter of the Arrhenius linear regression model;c is the second parameter of the Arrhenius linear regression model.

[0121] The least squares method is used to analyze the regression fitting, and the linear regression model parameters are obtained as follows:

[0122]

[0123] Wherein, m is the number of temperature groups in the performance degradation test; i2 is the temperature sequence number in the performance degradation test; is the average product of the test temperature and aging rate parameter after data processing, is the average value of the test temperature after data processing; is the average value of the aging rate parameter after data processing,

[0124] Step S3: Determine the working state of the aviation rubber static seal ring according to the deformation rate of the aviation rubber static seal ring; the sealing state judgment standard of the aviation rubber static seal ring based on the required threshold is:

[0125]

[0126] Among them, ε0 is the judgment threshold of the sealing demand of the aviation rubber ring; ε i S is the deformation rate of aviation rubber static seal ring; i Represents the working state of the rubber ring, S i =1 is the normal sealing state, S i =0 means sealing failure state.

[0127] When the sealing state of the aviation rubber static seal ring is judged to be a normal sealing state S i =1, execute step S4 to perform life prediction.

[0128] When the sealing state of the aviation rubber static seal ring is judged as a sealing failure state S i =0, then step S4 is not executed, indicating that the seal fails and a new aviation rubber static seal ring is replaced.

[0129] Step S4: Establish an aging prediction model for the aviation rubber static seal ring under the target working condition, and the life prediction result of the aviation rubber static seal ring; the aging rate parameter prediction value K at the target temperature of 150 degrees Celsius is:

[0130]

[0131] The aging constant K at 150 degrees Celsius is calculated to be 0.1424, and the aging prediction model at 150 degrees Celsius is established:

[0132]

[0133] in:

[0134] Calculate the service life of the rubber ring at 150 degrees Celsius:

[0135]

[0136] Among them, t is the life prediction result of aviation rubber static seal ring; is the predicted value of the aging rate parameter at the target temperature; is the predicted value of the test parameters at the target temperature.

[0137] like Figure 5 The figure shows the validation effect of the aging prediction model of the present invention; according to engineering experience, 40% is taken as the failure threshold, and the life of the sealing ring is estimated to be 63h at 150°C. The model can be validated according to the experimental data, and it is found that the model accuracy rate reaches 92.64%. The specific results are shown in Table 4.

[0138] Table 4 Life prediction results

[0139] Predicted lifespan / h Actual lifespan / h Accuracy / % 63 68 92.64

[0140] The beneficial effects of the present invention are as follows: an embodiment of the present invention provides a method for predicting the life of an aviation rubber static seal ring based on temperature analysis. In the embodiment, the Arrhenius extreme high temperature condition is injected into the kinetic curve performance degradation model, and the accuracy of the established aging prediction model is 92.64%. The life prediction is accurately completed within the acceptable error range of 10%, reflecting the aging process data, realizing the static seal life prediction, and through the high temperature accelerated test, the test cycle is effectively shortened, and important data on the aging of the seal ring can be obtained in a relatively short time, which is of great significance for guiding the static seal ring product design, optimizing material selection and improving the production and manufacturing process.

[0141] The embodiments described above are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for predicting the life of an aviation rubber static seal ring based on temperature analysis, characterized in that: It includes: S1: Perform an aging temperature test on the aviation rubber static seal ring to obtain the performance parameters of the aviation rubber static seal ring; Set the aging temperature and test time for the aging temperature test of the aviation rubber static seal ring, and obtain the temperature, time and performance parameters of the aviation rubber static seal ring; S2: Establish the dynamic curve performance degradation model of aviation rubber static seal ring, and estimate the aging parameters, test parameters and aging rate parameters by successive approximation method and least square method; S21: establishing a dynamic curve performance degradation model of the aviation rubber static seal ring according to the temperature, time and performance parameters of the aviation rubber static seal ring in step S1, and predicting the aging degree of the aviation rubber static seal ring; S22: Estimate the aging parameter α of the aviation rubber static seal ring by the successive approximation method, specifically: in, is the predicted value of the compression set retention rate of the jth aviation rubber static seal ring; It is the experimental value of compression permanent deformation retention rate of aviation rubber static seal ring; is the predicted value of the test parameter of a single group; is the predicted value of a single group of aging rate parameters; α is the aging parameter of the aviation rubber static seal ring, 0<α<1; min I is the minimization objective function value; is the test time after data processing; i1 is the test temperature stress group ordinal number; j is the test time group ordinal number; n1 is the total number of test temperature stress groups; n2 is the total number of test time groups; e is a natural constant; S23: Take the natural logarithm of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring in step S21, convert the dynamic curve into a straight line, analyze the regression parameters by the least squares method, and obtain the test parameter B and aging rate parameter K of the aviation rubber static seal ring: Among them, K is the aging rate parameter of the aviation rubber static seal ring; B is the test parameter of the aviation rubber static seal ring; n is the number of samples in the performance degradation test; i is the sample ordinal number in the performance degradation test; b is the first parameter of the linear regression model; x i is the test time after data processing, y i is the deformation rate of the sealing ring after data processing, y i =ln(1-ε i ); is the average product of the test time and the sealing ring deformation rate after data processing, is the average value of the test time after data processing, is the average value of the sealing ring deformation rate after data processing, a is the second parameter of the linear regression model; S24: Establish the Arrhenius model of the aviation rubber static seal ring to predict the aging rate parameters at the target temperature; take the natural logarithm of both ends of the Arrhenius model of the aviation rubber static seal ring, perform regression parameter analysis by the least squares method, and then determine the predicted value of the aging rate parameter and the predicted values ​​of the test parameters S3: Determine the working state of the aviation rubber static seal ring according to the deformation rate of the aviation rubber static seal ring; the sealing state judgment standard of the aviation rubber static seal ring based on the demand threshold is: Among them, ε0 is the judgment threshold of the sealing demand of the aviation rubber ring; ε i S is the deformation rate of aviation rubber static seal ring; i Represents the working state of the rubber ring, S i =1 is the normal sealing state, S i =0 means sealing failure state; When the sealing state of the aviation rubber static seal ring is judged to be a normal sealing state S i =1, then execute step S4 to perform life prediction; When the sealing state of the aviation rubber static seal ring is judged as a sealing failure state S i =0, then step S4 is not executed, indicating that the seal fails and a new aviation rubber static seal ring is replaced; S4: Establish an aging prediction model for the aviation rubber static seal ring under the target working condition. The life prediction result of the aviation rubber static seal ring is: Among them, t is the life prediction result of aviation rubber static seal ring; is the predicted value of the aging rate parameter at the target temperature; is the predicted value of the test parameter at the target temperature.

2. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: The requirements for obtaining the temperature, time and performance parameters of the aviation rubber static seal ring in step S1 are specifically: The performance parameter of the aviation rubber static seal ring requires that the compression permanent deformation at each set test temperature is less than or equal to 20%; Four detection points are evenly set on the radial and axial circumferences of the aviation rubber static seal ring, and their cross-sectional diameters are measured, and their arithmetic mean is taken as the detection result of the deformation of the aviation rubber static seal ring; the assembly of the aviation rubber static seal ring is taken out according to the set test time, cooled at room temperature for 1 hour, and then the assembly is opened, and the aviation rubber static seal ring is cooled and restored for 24 hours, and the cross-sectional heights of the four evenly distributed points on each seal ring are measured respectively, and the arithmetic mean is taken, and the initial value and the end value of the performance parameter are recorded.

3. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: The dynamic curve performance degradation model of the aviation rubber static seal ring in step S21 is specifically: Taking compression permanent deformation as the performance degradation parameter of aviation rubber static seal ring, a performance degradation trajectory model of compression permanent deformation and service time is established under each test temperature stress. The static seal ring aging prediction model obtained is: Among them, C is the compression permanent deformation degree of the aviation rubber static seal ring; h0 is the original cross-sectional diameter of the seal ring; h1 is the height of the seal groove of the test fixture; and h2 is the radial cross-sectional height of the seal ring after deformation.

4. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: The predicted value of the single group test parameter in step S22 for: in, is the predicted value of the second parameter of the linear regression model; is the predicted value of the first parameter of the linear regression model.

5. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: The predicted value of the single group test parameter in step S22 for: in, is the predicted value of the second parameter of the linear regression model.

6. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: In step S23, the natural logarithms of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring are taken, the dynamic curve is converted into a straight line, and the regression parameters are analyzed by the least squares method, specifically: Taking the natural logarithm of both ends of the dynamic curve performance degradation model of the aviation rubber static seal ring, the aging model of the aviation rubber static seal ring is obtained as follows: ln(1-C)=lnB-Kt α Let a = ln(B), b = -K, x = t α , y = ln(1-C), and the linear regression model of the aviation rubber static seal ring is obtained as follows: y=a+b·x The least squares method is used to analyze the regression fitting, and the linear regression model parameters are obtained as follows:

7. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: In step S24, the natural logarithms of both ends of the Arrhenius model of the aviation rubber static seal ring are taken, and regression parameter analysis is performed by the least squares method, specifically: Aging rate parameter K at target temperature t The Arrhenius model that conforms to the thermodynamic temperature T is: Where A is the frequency factor; T is the thermodynamic target temperature of the aging test; E is the apparent activation energy; K t is the aging rate parameter at the target temperature; R is the activation energy of the failure mechanism; By solving the aging rate parameter K at the target temperature t The relationship between the thermodynamic temperature T can be used to derive the aging rate parameter K at the target temperature. t The value of the Arrhenius model is taken as the natural logarithm of the parameters at both ends, and z=ln(K i ), c = ln(A), Establish the aging rate parameter K at the target temperature t The linear regression model between and thermodynamic temperature T is: z=d+ck Where k is the test temperature after data processing, z is the aging rate parameter after data processing, z = ln(K i );d is the first parameter of the Arrhenius linear regression model;c is the second parameter of the Arrhenius linear regression model; The least squares method is used to analyze the regression fitting, and the linear regression model parameters are obtained as follows: Wherein, m is the number of temperature groups in the performance degradation test; i2 is the temperature sequence number in the performance degradation test; is the average product of the test temperature and aging rate parameter after data processing, is the average value of the test temperature after data processing; is the average value of the aging rate parameter after data processing, n is the number of samples in the performance degradation test.

8. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: The predicted values ​​of the test parameters at the target temperature in step S4 for: in, is the predicted value of the test parameter at the target temperature.

9. The method for predicting the life of an aviation rubber static seal ring based on temperature analysis according to claim 1 is characterized in that: The predicted value of the aging rate parameter at the target temperature in step S4 for: in, is the predicted value of the aging rate parameter at the target temperature; d is the first parameter of the Arrhenius linear regression model.

Images