Flange sealing surface damage assessment method and device based on leakage rate

Abstract

The invention provides a flange sealing surface damage assessment method and device based on a leakage rate. The method comprises the following steps: obtaining a leakage rate formula reflecting the influence of a flange sealing surface defect according to a seepage principle; performing a leakage experiment on the customized damaged flange to fit correction parameters in a leakage rate formula to obtain a corrected leakage rate formula; and flange damage parameters are sampled through a Bayesian formula, sampling data are substituted into the corrected leakage rate formula to obtain a leakage rate calculation value, posterior distribution of the damage parameters under the given leakage rate is determined, and the damage grade corresponding to the posterior distribution of the damage parameter with the maximum probability is selected as an evaluation result. According to the method, the damage of the flange sealing surface can be quickly evaluated based on the direct observation data of the leakage rate, a complicated surface appearance scanning step is not needed, the evaluation process is simplified, the practical engineering application is facilitated, the sealing and safety performance of equipment can be guaranteed, and the method has high application and popularization values.

Description

Technical Field

[0001] The present invention relates to the technical field of sealing device damage assessment, and particularly to a method and device for flange sealing surface damage assessment based on leakage rate. Background Art

[0002] Leakage is one of the main causes of accidents in chemical production plants. As a key connecting component for fluid transmission and exchange between two pipelines or equipment in petrochemical plants, the sealing effect of the flange is directly related to production safety, public safety, and social and economic development. Taking a 300,000-ton / year chlor-alkali plant as an example, hundreds of its sealing points fail every year, and some gaskets need to be replaced once a month, with serious "leakage" of the medium.

[0003] The main reason for the above problems is that the flanges of chemical plants usually need to face strong acid and alkali medium environments. Even if they meet the strength design requirements, damage such as pitting corrosion, crevice corrosion, and crack corrosion is likely to occur on the flange sealing surface, resulting in pores between the flange sealing surface and the gasket, and further leading to sealing failure.

[0004] Current research on flange sealing has considered the influence of many factors, such as bolt preloading conditions, high and low temperature sealing environments, gasket models, and load vibration, but has not considered the influence of sealing surface damage on the leakage rate. In addition, since the determination of flange sealing strength by gasket factor and minimum gasket preloading specific pressure was proposed, flange leakage rate assessment methods based on seepage theory, fractal theory, etc. have been frequently reported, but there is still a lack of an assessment method that correlates the damage characteristics of the flange sealing surface with the leakage rate. Summary of the Invention

[0005] In view of this, the present invention provides a method and device for flange sealing surface damage assessment based on leakage rate to solve at least one of the above-mentioned problems.

[0006] To achieve the above object, the present invention adopts the following solutions:

[0007] According to a first aspect of the present invention, there is provided a method for flange sealing surface damage assessment based on leakage rate, the method comprising:

[0008] Obtaining a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle;

[0009] Customizing damage on the flange sealing surface, and performing a leakage experiment on the damaged flange to fit the correction parameters in the leakage rate formula to obtain a corrected leakage rate formula;

[0010] Under a determined flange damage rating, based on the measured leakage rate value of the flange to be evaluated, sample the flange damage parameters through Bayes' formula, substitute the sampled data into the corrected leakage rate formula to obtain the calculated leakage rate value, thereby determining the posterior distribution of the damage parameters under a given leakage rate, and select the damage level corresponding to the posterior distribution of the damage parameters with the highest probability as the evaluation result of the damage of the flange sealing surface to be evaluated.

[0011] As an embodiment of the present invention, in the above method, the leakage rate formula reflecting the influence of the flange sealing surface defect obtained according to the seepage principle includes:

[0012] Determine the contact radius of the contact point based on Hertz contact mechanics theory;

[0013] Obtain the porosity based on the contact radius;

[0014] Based on the porosity, calculate the permeability using the Kozeny-Carman formula;

[0015] Based on the permeability, obtain the gas seepage velocity using Darcy's law;

[0016] Based on the gas seepage velocity and the seepage cross-sectional area of the flange sealing interface, obtain the flange leakage rate formula, and the flange leakage rate formula is as follows:

[0017] Q = u×S;

[0018] Wherein, Q is the flange leakage rate; u is the gas seepage velocity; S is the seepage cross-sectional area of the flange sealing interface;

[0019] Introduce damage parameters to correct the flange leakage rate, and obtain the following leakage rate formula reflecting the influence of the flange sealing surface defect:

[0020]

[0021] Wherein, α is a correction parameter added to consider the error between theory and practice; Collectively referred to as damage parameters, is the dimensionless damage area opening angle, is the average depth of the sealing surface damage, is the average radial projection of the sealing surface damage; k is the permeability; k' is the permeability after considering the porosity correction; R is the average radius of the flange sealing surface; μ is the viscosity coefficient of the sealing medium; Δp is the pressure difference between the sealing medium and the external environment; L is the contact width of the sealing surface.

[0022] As an embodiment of the present invention, in the above method, the damage parameter is divided into several levels, and the damage level is the highest rating among the three damage parameters when the overall damage of the flange sealing surface is rated.

[0023] As an embodiment of the present invention, in the above method, customizing damage to the flange sealing surface and performing a leakage test on the damaged flange to fit the correction parameters in the leakage rate formula includes:

[0024] Customizing pits or scratch damages with different degrees on the flange sealing surface to obtain known damage parameters and flange specimens;

[0025] Performing a leakage test on the flange specimens to measure the leakage rate Q under different damage degrees;

[0026] Substituting the measured leakage rate Q and the corresponding damage parameters and into the leakage rate formula reflecting the influence of flange sealing surface defects, and using the least squares method to fit the value of the correction parameter α.

[0027] As an embodiment of the present invention, in the above method, under a determined flange damage rating, based on the measured leakage rate value of the flange to be evaluated, sampling the flange damage parameters through the Bayesian formula, substituting the sampled data into the corrected leakage rate formula to obtain a leakage rate calculated value, thereby determining the posterior distribution of the damage parameters under a given leakage rate, and selecting the damage level corresponding to the posterior distribution of the damage parameters with the maximum probability as the evaluation result of the flange sealing surface damage to be evaluated includes:

[0028] Using the Bayesian formula to correlate the leakage rate and the flange sealing surface damage level:

[0029]

[0030] In the above formula: Q represents the leakage rate; d represents the flange sealing surface damage level; P(d|Q) represents the probability that the flange sealing surface damage level is d under the condition that the leakage rate is Q, that is, the posterior probability; P(d) represents the probability that the flange sealing surface damage level is d, that is, the prior probability; P(Q) represents the probability of monitoring a leakage rate of Q; P(Q|d) represents the probability that the leakage rate is Q when the flange sealing surface damage level is d, that is, the likelihood probability;

[0031] According to the distribution of the posterior probability P(d|Q), select the damage level corresponding to the posterior distribution of the damage parameters with the maximum probability as the evaluation result of the flange sealing surface damage to be evaluated.

[0032] According to the second aspect of the present invention, there is provided a flange sealing surface damage evaluation device based on the leakage rate, and the device includes:

[0033] A formula acquisition unit for obtaining a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle;

[0034] A formula correction unit, configured to customize damages on a flange sealing surface, and perform a leakage test on the flange after the customization of damages to fit correction parameters in the leakage rate formula, so as to obtain a corrected leakage rate formula;

[0035] A damage assessment unit, configured to, under a determined flange damage rating, sample flange damage parameters through a Bayesian formula based on the measured leakage rate value of the flange to be evaluated, substitute the sampled data into the corrected leakage rate formula to obtain a leakage rate calculated value, thereby determining the posterior distribution of the damage parameters at a given leakage rate, and selecting the damage level corresponding to the posterior distribution of the damage parameters with the maximum probability as the evaluation result of the damage of the flange sealing surface to be evaluated.

[0036] As an embodiment of the present invention, the above formula acquisition unit includes:

[0037] A contact parameter determination module, configured to determine the contact radius of a contact point based on the Hertz contact mechanics theory;

[0038] A porosity acquisition module, configured to obtain the porosity based on the contact radius;

[0039] A permeability acquisition module, configured to calculate and obtain the permeability based on the porosity by using the Kozeny-Carman formula;

[0040] A seepage velocity acquisition module, configured to obtain the gas seepage velocity based on the permeability by using Darcy's law;

[0041] A leakage rate formula acquisition module, configured to obtain a flange leakage rate formula based on the gas seepage velocity and the seepage cross-sectional area of the flange sealing interface, and the flange leakage rate formula is as follows:

[0042] Q = u×S;

[0043] wherein, Q is the flange leakage rate; u is the gas seepage velocity; S is the seepage cross-sectional area of the flange sealing interface;

[0044] A leakage rate formula correction module, configured to correct the flange leakage rate by introducing damage parameters to obtain a leakage rate formula reflecting the influence of flange sealing surface defects as follows:

[0045]

[0046] wherein, α is a correction parameter added to consider the error between theory and practice; collectively referred to as damage parameters, is a dimensionless damage area opening angle, is the average depth of the sealing surface damage, The radial average projection of the seal surface damage; k is the permeability; k′ is the permeability after considering the porosity correction; R is the average radius of the flange seal surface; μ is the viscosity coefficient of the sealing medium; Δp is the pressure difference between the sealing medium and the external environment; L is the contact width of the seal surface.

[0047] As an embodiment of the present invention, the above damage parameters are divided into several levels, and the damage level in the overall damage rating of the flange seal surface is the highest rating among the three damage parameters.

[0048] As an embodiment of the present invention, the above formula correction unit includes:

[0049] A damage customization module for customizing different degrees of pits or scratches on the flange seal surface to obtain a flange specimen with known damage parameters and ;

[0050] A leakage experiment module for controlling a leakage experiment on the flange specimen and measuring the leakage rate Q under different damage degrees;

[0051] A correction parameter acquisition module for substituting the measured leakage rate Q and the corresponding damage parameters and into the leakage rate formula reflecting the influence of the flange seal surface defect, and obtaining the value of the correction parameter α by using the least squares method for fitting.

[0052] As an embodiment of the present invention, the above damage assessment unit is specifically used for:

[0053] Associating the leakage rate and the flange seal surface damage level by using the Bayesian formula:

[0054]

[0055] In the above formula: Q represents the leakage rate; d represents the flange seal surface damage level; P(d|Q) represents the probability that the flange seal surface damage level is d under the condition that the leakage rate is Q, that is, the posterior probability; P(d) represents the probability that the flange seal surface damage level is d, that is, the prior probability; P(Q) represents the probability of monitoring the leakage rate Q; P(Q|d) represents the probability that the leakage rate is Q when the flange seal surface damage level is d, that is, the likelihood probability;

[0056] According to the distribution of the posterior probability P(d|Q), select the damage level corresponding to the posterior distribution of the damage parameter with the maximum probability as the evaluation result of the damage of the flange seal surface to be evaluated.

[0057] According to a third aspect of the present invention, there is provided an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the steps of the above method are implemented.

[0058] According to a fourth aspect of the present invention, there is provided a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above method are implemented.

[0059] According to a fifth aspect of the present invention, there is provided a computer program product, including a computer program / instructions. When the computer program / instructions are executed by a processor, the steps of the above method are implemented.

[0060] As can be seen from the above technical solutions, a method and device for evaluating flange sealing surface damage based on leakage rate provided by this application first obtain a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle; then customize damage to the flange sealing surface, and conduct a leakage experiment on the customized damaged flange to fit the correction parameters in the leakage rate formula, obtaining a corrected leakage rate formula; finally, under the determined flange damage rating, based on the measured leakage rate value of the flange to be evaluated, sample the flange damage parameters through the Bayesian formula, substitute the sampled data into the corrected leakage rate formula to obtain a leakage rate calculation value, thereby determining the posterior distribution of the damage parameters at a given leakage rate, and selecting the damage level corresponding to the posterior distribution of the damage parameters with the maximum probability as the evaluation result of the flange sealing surface damage to be evaluated. Therefore, this application can quickly evaluate the damage of the flange sealing surface based on the direct observation data of the leakage rate, without the need for complex surface topography scanning (such as scanning electron microscope scanning) steps, simplifies the evaluation process, is convenient for engineering practical applications, can ensure the sealing and safety performance of the equipment, and has high application and promotion value. Description of the Drawings

[0061] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. In the drawings:

[0062] Figure 1 is a schematic flow chart of a method for evaluating flange sealing surface damage based on leakage rate provided by an embodiment of this application;

[0063] Figure 2 is a schematic flow chart of a method for obtaining a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle provided by an embodiment of this application;

[0064] Figure 3 It is an evaluation diagram of flange sealing surface damage with three levels provided by an embodiment of the present application;

[0065] Figure 4 It is a schematic flow diagram of correcting parameters to obtain a corrected leakage rate formula provided by an embodiment of the present application;

[0066] Figure 5 It is a schematic structural diagram of a leakage experiment device provided by an embodiment of the present application;

[0067] Figure 6 It is a schematic diagram of the final evaluation result provided by an embodiment of the present application;

[0068] Figure 7 It is a schematic structural diagram of a flange sealing surface damage evaluation device based on leakage rate provided by an embodiment of the present application;

[0069] Figure 8 It is a schematic structural diagram of a formula acquisition unit provided by an embodiment of the present application;

[0070] Figure 9 It is a schematic structural diagram of a formula correction unit provided by an embodiment of the present application;

[0071] Figure 10 It is a schematic block diagram of the system composition of an electronic device provided by another embodiment of the present application. Detailed implementation manners

[0072] The data migration method and device of the distributed cache system provided by the embodiments of the present invention can be used in the financial field and other fields. It should be noted that the data migration method and device of the distributed cache system of the present invention can be used in the financial field and can also be used in any field other than the financial field. The present invention does not limit the data migration method and device of the distributed cache system.

[0073] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer and more understandable, the following further describes the embodiments of the present invention in detail with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but do not limit the present invention.

[0074] As Figure 1 shown is a schematic flow diagram of a flange sealing surface damage evaluation method based on leakage rate provided by an embodiment of the present application. The method includes the following steps:

[0075] Step S101: Obtain a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle.

[0076] The core of this step S101 is to establish a mathematical relationship between the leakage rate and the flange sealing surface damage parameters, thereby reflecting the influence of the flange sealing surface defects on the leakage rate. In the embodiment of the present application, based on the seepage theory, considering the influence of the flange sealing surface damage (such as pits, scratches) on the seepage channel, a leakage rate formula including damage parameters (including the dimensionless damage area angle average depth of the sealing surface damage average radial projection of the sealing surface damage ) and correction parameters is derived. The derivation process of this formula involves Hertz contact mechanics theory, Kozeny-Carman formula, and Darcy's law, etc., which are used to calculate the contact point geometric parameters, permeability, and gas seepage velocity respectively.

[0077] The following further details how to obtain the leakage rate formula reflecting the influence of the flange sealing surface defects according to the seepage principle in this step:

[0078] As Figure 2 shown in the flow chart of obtaining the leakage rate formula reflecting the influence of the flange sealing surface defects according to the seepage principle provided by the embodiment of the present application, it includes the following sub-steps:

[0079] Step S1011: Determine the contact radius of the contact point based on Hertz contact mechanics theory.

[0080] In this embodiment, for the sake of simplifying the calculation, it is assumed that the contact of the flange sealing surface is the contact between a rigid rough surface and a smooth plane. Each contact point or micro-convex body on the rough surface is approximately a spherical body with a radius of R, and the sealing force received is F. The calculation formula of the contact radius is as follows:

[0081]

[0082] where, a represents the contact radius, and E represents the equivalent composite elastic modulus of the sealing material.

[0083] Step S1012: Obtain the porosity based on the contact radius.

[0084] The calculation formula of the porosity here is as follows:

[0085]

[0086] where, ε represents the porosity.

[0087] Step S1013: Calculate the permeability based on the porosity using the Kozeny-Carman formula.

[0088] The Kozeny-Carman formula is an empirical formula for calculating the permeability of porous media. It relates the permeability to the porosity of the porous media, the pore structure, and the fluid viscosity. In this embodiment, the calculation formula for permeability is as follows:

[0089]

[0090] Where k represents the permeability; k′ represents the permeability after considering the porosity correction, p represents the medium pressure under the sealed condition, and b represents the gas slip factor.

[0091] Step S1014: Based on the permeability, use Darcy's law to obtain the gas seepage velocity.

[0092] Darcy's law describes the basic law of fluid seepage in porous media. In this embodiment, the formula for the gas seepage velocity obtained using Darcy's law is as follows:

[0093]

[0094] Where u represents the gas seepage velocity; μ represents the viscosity coefficient of the sealing medium; L represents the contact width of the sealing surface; Δp represents the pressure difference between the sealing medium and the external environment.

[0095] Step S1015: Based on the gas seepage velocity and the seepage cross-sectional area of the flange sealing interface, obtain the flange leakage rate formula, and the flange leakage rate formula is as follows:

[0096] Q = u × S;

[0097] Where Q is the flange leakage rate; u is the gas seepage velocity; S is the seepage cross-sectional area of the flange sealing interface.

[0098] Step S1016: Introduce a damage parameter to correct the flange leakage rate to obtain the following leakage rate formula reflecting the influence of flange sealing surface defects:

[0099]

[0100] Where α is a correction parameter added to account for the error between theory and practice; Collectively referred to as the damage parameter, Is the dimensionless damage area opening angle, Is the average depth of the sealing surface damage, Is the average radial projection of the sealing surface damage; k is the permeability; k′ is the permeability after considering the porosity correction; R is the average radius of the flange sealing surface; μ is the viscosity coefficient of the sealing medium; Δp is the pressure difference between the sealing medium and the external environment; L is the contact width of the sealing surface.

[0101] Through the above steps S1011 - S1016, a leakage rate formula containing the unknown correction parameter α can be obtained, which can reflect the influence of flange sealing surface defects on the leakage rate.

[0102] Preferably, the above damage parameters are divided into several levels, and the damage level during the overall damage rating of the flange sealing surface is the highest rating among the three damage parameters. For example, in an embodiment of the present application, the above damage parameters are divided into three levels: primary loss, secondary loss, and tertiary damage. The final overall damage level of the flange sealing surface is the highest level among these three parameter levels. This means that if is secondary damage, is primary damage, is tertiary damage, then the final overall damage level of the flange sealing surface will be rated as tertiary damage. As Figure 3 shown, this is the flange sealing surface damage evaluation diagram with three levels provided for the flange pipe diameter of 15mm - 75mm in this embodiment, where φ, and are each divided into three levels.

[0103] Step S102: Customize damage on the flange sealing surface, and conduct a leakage experiment on the damaged flange to fit the correction parameter in the leakage rate formula, obtaining a corrected leakage rate formula.

[0104] To determine the unknown correction parameter in the leakage rate formula derived in step S101, a leakage experiment needs to be conducted. In the solution of the present application, different degrees of pit or scratch damage are artificially created on the flange sealing surface first, and then a leakage experiment is carried out. During the experiment, the leakage rate under different damage degrees needs to be measured, and these experimental data are fitted with the leakage rate formula derived in step S101. Fitting methods such as the least squares method can be used. Finally, the value of the unknown correction parameter in the formula is obtained, thereby obtaining a corrected leakage rate formula, which can more accurately predict the leakage rate under the actual flange sealing surface damage situation.

[0105] Therefore, preferably, as Figure 4 shown, this step can further include the following sub - steps:

[0106] Step S1021: Customize different degrees of pit or scratch damage on the flange sealing surface to obtain a flange specimen with known damage parameters and of.

[0107] Step S1022: Conduct a leakage experiment on the flange specimen to measure the leakage rate Q under different damage degrees.

[0108] AsFigure 5 The following is a schematic structural diagram of a leakage experiment device provided by an embodiment of the present application, including a helium gas cylinder, a mass spectrometer leak detector, a flange structure specimen to be inspected, a leak detection chamber, a vacuum pump, a data acquisition system (computer), etc. During the test, the bolt pre-tightening force of the flange seal can be adjusted through a strain gauge. After the pre-tightening force is given, the valve of the helium gas cylinder is opened, and the mass spectrometer leak detector can automatically detect the current helium gas leakage rate.

[0109] Step S1023: The measured leakage rate Q and the corresponding damage parameters and are substituted into the leakage rate formula reflecting the influence of flange seal surface defects, and the value of the correction parameter α is obtained by least squares fitting.

[0110] The experimental parameters such as pre-tightening force, pressure, temperature, etc. and the corresponding damage parameters and are substituted into the leakage rate correction formula to obtain the theoretical value of the leakage rate containing unknowns. Subsequently, a fitting method such as the least squares method is used to obtain the leakage rate distribution curve closest to the experimental value, so as to obtain the approximate value of α.

[0111] Step S103: Under the determined flange damage rating, based on the measured value of the leakage rate of the flange to be evaluated, the flange damage parameters are sampled through the Bayesian formula. The sampled data is substituted into the corrected leakage rate formula to obtain the leakage rate calculation value, so as to determine the posterior distribution of the damage parameters at a given leakage rate. The damage level corresponding to the posterior distribution of the damage parameter with the highest probability is selected as the evaluation result of the flange seal surface damage to be evaluated.

[0112] This step is to evaluate the flange seal surface damage level using Bayesian inference. Preferably, this step may specifically include:

[0113] Relate the leakage rate and the flange seal surface damage level using the Bayesian formula:

[0114]

[0115] In the above formula: Q represents the leakage rate; d represents the flange seal surface damage level; P(d|Q) represents the probability that the flange seal surface damage level is d under the condition that the leakage rate is Q, that is, the posterior probability; P(d) represents the probability that the flange seal surface damage level is d, that is, the prior probability; P(Q) represents the probability of monitoring a leakage rate of Q; P(Q|d) represents the probability that the leakage rate is Q when the flange seal surface damage level is d, that is, the likelihood probability.

[0116] The integral term in the denominator of Bayesian inference is usually difficult to calculate. In this embodiment, the following proportional relationship can be introduced:

[0117] P(d|Q) ∝ P(Q|d)P(d).

[0118] Meanwhile, to calculate the posterior probability, further consider that P(d) is the prior probability of flange sealing surface damage. Since any information about the damage is unknown, in this embodiment, the prior probability P(d) of flange sealing surface damage is defined as a uniform probability within a specified interval.

[0119] For the likelihood probability P(Q|d), it is simplified to a normal distribution as follows:

[0120]

[0121] where Q i represents the measured value of the leakage rate, C i represents the calculated value obtained through the leakage rate correction formula. It is obtained by sampling the flange damage parameters through Bayes' formula and then substituting the sampled data into the corrected leakage rate formula. The σ 2 represents the variance of Q i in several measurements.

[0122] Multiply the prior probability and the likelihood probability to obtain the posterior probability P(d|Q).

[0123] Obtain the distribution of the posterior probability P(d|Q) through sampling. For example, methods such as Markov chain Monte Carlo method and Gaussian sampling can be used for sampling.

[0124] According to the distribution of the posterior probability P(d|Q), select the damage level corresponding to the posterior distribution of the damage parameter with the maximum probability as the evaluation result of the flange sealing surface damage to be evaluated. In an embodiment of the present application, the final evaluation result is as Figure 6 shown. It can be seen that the damage levels corresponding to the three damage parameters are grade two, grade two, and grade one respectively. Therefore, the grade two damage is taken as the evaluation result of the current flange sealing surface damage.

[0125] As can be seen from the above technical solutions, a method for evaluating the damage of a flange sealing surface based on the leakage rate provided by the present application first obtains a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle; then customizes damage to the flange sealing surface, and conducts a leakage experiment on the damaged flange to fit the correction parameters in the leakage rate formula to obtain a corrected leakage rate formula; finally, under the determined flange damage rating, based on the measured leakage rate value of the flange to be evaluated, samples the flange damage parameters through the Bayesian formula, substitutes the sampled data into the corrected leakage rate formula to obtain a leakage rate calculation value, thereby determining the posterior distribution of the damage parameters at a given leakage rate, and selects the damage level corresponding to the posterior distribution of the damage parameters with the highest probability as the evaluation result of the damage of the flange sealing surface to be evaluated. Therefore, the present application can quickly evaluate the damage of the flange sealing surface based on the direct observation data of the leakage rate, without the need for complex surface topography scanning (such as scanning electron microscope scanning) steps, simplifies the evaluation process, is convenient for engineering practical applications, can ensure the sealing and safety performance of equipment, and has high application and promotion value.

[0126] As Figure 7 shown in the structural schematic diagram of a device for evaluating the damage of a flange sealing surface based on the leakage rate provided by an embodiment of the present application, the device includes: a formula acquisition unit 710, a formula correction unit 720, and a damage evaluation unit 730, which are connected in sequence. Among them:

[0127] The formula acquisition unit 710 is used to obtain a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle.

[0128] The formula correction unit 720 is used to customize damage to the flange sealing surface, and conduct a leakage experiment on the damaged flange to fit the correction parameters in the leakage rate formula to obtain a corrected leakage rate formula.

[0129] The damage evaluation unit 730 is used to, under the determined flange damage rating, based on the measured leakage rate value of the flange to be evaluated, sample the flange damage parameters through the Bayesian formula, substitute the sampled data into the corrected leakage rate formula to obtain a leakage rate calculation value, thereby determining the posterior distribution of the damage parameters at a given leakage rate, and selecting the damage level corresponding to the posterior distribution of the damage parameters with the highest probability as the evaluation result of the damage of the flange sealing surface to be evaluated.

[0130] Preferably, as Figure 8 shown, the above formula acquisition unit 710 includes:

[0131] The contact parameter determination module 711 is used to determine the contact radius of the contact point based on the Hertz contact mechanics theory.

[0132] The porosity acquisition module 712 is used to obtain the porosity based on the contact radius.

[0133] A permeability acquisition module 713, configured to calculate the permeability based on the porosity by using the Kozeny-Carman formula.

[0134] A seepage velocity acquisition module 714, configured to obtain the gas seepage velocity based on the permeability by using Darcy's law.

[0135] A leakage rate formula acquisition module 715, configured to obtain a flange leakage rate formula based on the gas seepage velocity and the seepage cross-sectional area of the flange sealing interface. The flange leakage rate formula is as follows:

[0136] Q = u × S;

[0137] where Q is the flange leakage rate; u is the gas seepage velocity; and S is the seepage cross-sectional area of the flange sealing interface.

[0138] A leakage rate formula correction module 716, configured to correct the flange leakage rate by introducing a damage parameter to obtain a leakage rate formula reflecting the influence of the flange sealing surface defect as follows.

[0139]

[0140] where α is a correction parameter added to consider the error between theory and practice; collectively referred to as damage parameters, is the dimensionless damage area opening angle, is the average depth of the sealing surface damage, is the average radial projection of the sealing surface damage; k is the permeability; k' is the permeability after considering the porosity correction; R is the average radius of the flange sealing surface; μ is the viscosity coefficient of the sealing medium; Δp is the pressure difference between the sealing medium and the external environment; and L is the contact width of the sealing surface.

[0141] Preferably, the above damage parameters are divided into several levels, and the damage level is the highest rating among the three damage parameters when the overall damage of the flange sealing surface is rated.

[0142] Preferably, as Figure 9 shown, the above formula correction unit 720 includes:

[0143] A damage customization module 721, configured to customize different degrees of pit or scratch damage on the flange sealing surface to obtain a flange specimen with known damage parameters and of.

[0144] A leakage experiment module 722, configured to control a leakage experiment on the flange specimen and measure the leakage rate Q under different damage degrees.

[0145] The correction parameter acquisition module 723 is configured to use the measured leakage rate Q and the corresponding damage parameter and substitute them into the leakage rate formula reflecting the influence of the flange sealing surface defect, and use the least squares method to fit to obtain the value of the correction parameter α.

[0146] Preferably, the above-mentioned damage assessment unit 730 is specifically configured to:

[0147] Use Bayes' formula to correlate the leakage rate and the flange sealing surface damage level:

[0148]

[0149] In the above formula: Q represents the leakage rate; d represents the flange sealing surface damage level; P(d|Q) represents the probability that the flange sealing surface damage level is d under the condition that the leakage rate is Q, that is, the posterior probability; P(d) represents the probability that the flange sealing surface damage level is d, that is, the prior probability; P(Q) represents the probability of monitoring the leakage rate of Q; P(Q|d) represents the probability that the leakage rate is Q when the flange sealing surface damage level is d, that is, the likelihood probability;

[0150] Define the prior probability P(d) of the flange sealing surface damage as a uniform probability within a specified interval;

[0151] For the likelihood probability P(Q|d), simplify it to a normal distribution as follows:

[0152]

[0153] Where Q i represents the measured value of the leakage rate, C i represents the calculated value obtained through the leakage rate correction formula, and σ 2 represents the variance of Q i in several measurements;

[0154] Multiply the prior probability and the likelihood probability to obtain the posterior probability P(d|Q);

[0155] Obtain the distribution of the posterior probability P(d|Q) through sampling;

[0156] According to the distribution of the posterior probability P(d|Q), select the damage level corresponding to the posterior distribution of the damage parameter with the maximum probability as the evaluation result of the damage of the flange sealing surface to be evaluated.

[0157] As can be seen from the above technical solution, a flange seal surface damage assessment device provided by the present application first obtains a leakage rate formula reflecting the influence of flange seal surface defects according to the seepage principle; then customizes damage on the flange seal surface, and conducts a leakage experiment on the damaged flange to fit the correction parameters in the leakage rate formula to obtain a corrected leakage rate formula; finally, under the determined flange damage rating, based on the measured leakage rate value of the flange to be evaluated, samples are taken for the flange damage parameters through the Bayesian formula, and the sampled data is substituted into the corrected leakage rate formula to obtain a leakage rate calculation value, thereby determining the posterior distribution of the damage parameters at a given leakage rate, and selecting the damage level corresponding to the posterior distribution of the damage parameters with the highest probability as the evaluation result of the flange seal surface damage to be evaluated. Therefore, the present application can quickly evaluate the damage of the flange seal surface based on the direct observation data of the leakage rate, without the need for complex surface topography scanning (such as scanning electron microscope scanning) steps, simplifies the evaluation process, is convenient for engineering practical applications, can ensure the equipment sealing and safety performance, and has high application and promotion value.

[0158] An embodiment of the present invention further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the above method is implemented.

[0159] An embodiment of the present invention further provides a computer program product, including computer programs / instructions. When the computer programs / instructions are executed by a processor, the steps of the above method are implemented.

[0160] An embodiment of the present invention further provides a computer-readable storage medium, which stores a computer program for executing the above method.

[0161] As Figure 10 shown, the electronic device 600 may further include: a communication module 110, an input unit 120, an audio processor 130, a display 160, and a power supply 170. It should be noted that the electronic device 600 does not necessarily have to include Figure 10 all the components shown in Figure 10 ; in addition, the electronic device 600 may further include

[0162] As Figure 10 shown, the central processing unit 100 is sometimes also referred to as a controller or an operation control, and may include a microprocessor or other processor devices and / or logic devices. The central processing unit 100 receives inputs and controls the operations of the various components of the electronic device 600.

[0163] Among them, the memory 140 can be, for example, one or more of a buffer, a flash memory, a hard drive, a removable medium, a volatile memory, a non-volatile memory, or other suitable devices. The above information related to failures can be stored, and in addition, a program for executing relevant information can also be stored. And the central processing unit 100 can execute the program stored in the memory 140 to implement information storage or processing, etc.

[0164] The input unit 120 provides an input to the central processing unit 100. The input unit 120 is, for example, a key or a touch input device. The power supply 170 is used to supply power to the electronic device 600. The display 160 is used to display display objects such as images and texts. The display can be, for example, an LCD display, but is not limited thereto.

[0165] The memory 140 can be a solid-state memory. For example, it can be a read-only memory (ROM), a random access memory (RAM), a SIM card, etc. It can also be a memory that stores information even when powered off, can be selectively erased and has more data. An example of this memory is sometimes called an EPROM, etc. The memory 140 can also be some other type of device. The memory 140 includes a buffer memory 141 (sometimes called a buffer). The memory 140 can include an application / function storage unit 142, which is used to store application programs and function programs or the processes for operating the electronic device 600 through the central processing unit 100.

[0166] The memory 140 can also include a data storage unit 143, which is used to store data, such as contacts, digital data, pictures, sounds, and / or any other data used by the electronic device. The driver storage unit 144 of the memory 140 can include various drivers of the electronic device for communication functions and / or for executing other functions of the electronic device (such as a messaging application, an address book application, etc.).

[0167] The communication module 110 is a transmitter / receiver that transmits and receives signals via the antenna 111. The communication module 110 (transmitter / receiver) is coupled to the central processing unit 100 to provide input signals and receive output signals, which can be the same as in the case of a conventional mobile communication terminal.

[0168] Based on different communication technologies, in the same electronic device, multiple communication modules 110 can be provided, such as a cellular network module, a Bluetooth module, and / or a wireless local area network module, etc. The communication module 110 (transmitter / receiver) is also coupled to the speaker 131 and the microphone 132 via the audio processor 130 to provide an audio output via the speaker 131 and receive an audio input from the microphone 132, thereby implementing normal telecommunication functions. The audio processor 130 can include any suitable buffers, decoders, amplifiers, etc. In addition, the audio processor 130 is also coupled to the central processor 100, so that recording can be performed on the local machine through the microphone 132, and the sound stored on the local machine can be played through the speaker 131.

[0169] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) containing computer-usable program code.

[0170] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one or more of the flows Figure 1 or multiple flows and / or blocks

[0171] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including instruction means, and the instruction means implements the functions specified in Figure 1 one or more of the flows Figure 1 or multiple flows and / or blocks

[0172] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus, so that a series of operation steps are performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one process or a plurality of processes and / or blocks Figure 1 one process or a plurality of processes and / or blocks Figure 1 steps for implementing the functions specified in one block or a plurality of blocks.

[0173] Specific embodiments are used in the present invention to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; meanwhile, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A flange sealing surface damage assessment method based on leakage rate, characterized in that: The method comprises: Based on the seepage principle, the leakage rate formula reflecting the influence of flange sealing surface defects is obtained; Customized damage is performed on the flange sealing surface, and a leakage test is performed on the flange after customized damage to fit the correction parameters in the leakage rate formula to obtain a corrected leakage rate formula; Under the determined flange damage rating, based on the measured leakage rate value of the flange to be evaluated, the flange damage parameters are sampled using the Bayesian formula, and the sampled data are substituted into the modified leakage rate formula to obtain the calculated leakage rate value, thereby determining the posterior distribution of the damage parameters under the given leakage rate, and selecting the damage level corresponding to the posterior distribution of the damage parameters with the maximum probability as the evaluation result of the sealing surface damage of the flange to be evaluated.

2. The flange sealing surface damage assessment method based on leakage rate according to claim 1, characterized in that: The leakage rate formula reflecting the influence of flange sealing surface defects obtained according to the seepage principle includes: Determine the contact radius of the contact point based on Hertz contact mechanics theory; Obtaining a porosity based on the contact radius; Based on the porosity, the permeability is calculated using the Kozeny-Carman formula; Based on the permeability, the gas seepage velocity is obtained using Darcy's law; The flange leakage rate formula is obtained based on the gas seepage velocity and the seepage cross-sectional area of ​​the flange sealing interface. The flange leakage rate formula is as follows: Q = u × S; Wherein, Q is the flange leakage rate; u is the gas seepage velocity; S is the seepage cross-sectional area of ​​the flange sealing interface; The damage parameter is introduced to correct the flange leakage rate, and the following leakage rate formula reflecting the influence of flange sealing surface defects is obtained: Among them, α is the correction parameter added to consider the error between theory and practice; Collectively referred to as damage parameters, is the dimensionless damage area angle, is the average depth of damage to the sealing surface, is the radial average projection of the sealing surface damage; k is the permeability; k' is the permeability after porosity correction; R is the average radius of the flange sealing surface; μ is the viscosity coefficient of the sealing medium; Δp is the pressure difference between the sealing medium and the external environment; L is the contact width of the sealing surface.

3. The flange sealing surface damage assessment method based on leakage rate according to claim 2 is characterized in that: The damage parameters It is divided into several levels, and the damage level of the flange sealing surface overall damage rating is the highest rating among the three damage parameters.

4. The flange sealing surface damage assessment method based on leakage rate according to claim 2, characterized in that: The customizing of damage on the flange sealing surface and performing a leakage test on the flange after customizing the damage to fit the correction parameters in the leakage rate formula include: Customize different degrees of pits or scratches on the flange sealing surface to obtain known damage parameters and Flange test piece; A leakage test is performed on the flange specimen to measure the leakage rate Q at different damage degrees; The measured leakage rate Q and the corresponding damage parameter and Substituting into the leakage rate formula reflecting the influence of flange sealing surface defects, the value of the correction parameter α is obtained by using the least squares method for fitting.

5. The flange sealing surface damage assessment method based on leakage rate according to claim 1, characterized in that: The flange damage rating is determined, based on the measured leakage rate of the flange to be evaluated, the flange damage parameters are sampled by the Bayesian formula, and the sampled data is substituted into the modified leakage rate formula to obtain the leakage rate calculation value, so as to determine the posterior distribution of the damage parameter under the given leakage rate, and select the damage level corresponding to the posterior distribution of the damage parameter with the maximum probability as the evaluation result of the flange sealing surface damage to be evaluated, including: The Bayesian formula is used to correlate the leakage rate and the flange sealing surface damage level: In the above formula: Q represents the leakage rate; d represents the damage level of the flange sealing surface; P(d|Q) represents the probability that the damage level of the flange sealing surface is d under the condition that the leakage rate is Q, that is, the posterior probability; P(d) represents the probability that the damage level of the flange sealing surface is d, that is, the prior probability; P(Q) represents the probability of monitoring the leakage rate to be Q; P(Q|d) represents the probability that the leakage rate is Q when the damage level of the flange sealing surface is d, that is, the likelihood probability; According to the distribution of the posterior probability P(d|Q), the damage level corresponding to the posterior distribution of the damage parameter with the maximum probability is selected as the evaluation result of the damage of the flange sealing surface to be evaluated.

6. A flange sealing surface damage assessment device based on leakage rate, characterized in that: The device comprises: A formula acquisition unit, used to obtain a leakage rate formula reflecting the influence of flange sealing surface defects according to the seepage principle; A formula correction unit, used for customizing damage on the flange sealing surface, and performing a leakage experiment on the flange after customizing the damage to fit the correction parameters in the leakage rate formula to obtain a corrected leakage rate formula; The damage assessment unit samples the flange damage parameters through the Bayesian formula based on the actual leakage rate value of the flange to be assessed under the determined flange damage rating, substitutes the sampled data into the modified leakage rate formula to obtain the leakage rate calculation value, thereby determining the posterior distribution of the damage parameters under the given leakage rate, and selects the damage level corresponding to the posterior distribution of the damage parameters with the maximum probability as the assessment result of the damage to the sealing surface of the flange to be assessed.

7. The flange sealing surface damage assessment device based on leakage rate according to claim 6, characterized in that: The formula acquisition unit comprises: The contact parameter determination module is used to determine the contact radius of the contact point based on the Hertz contact mechanics theory; A porosity acquisition module, used for obtaining the porosity based on the contact radius; A permeability acquisition module, used to calculate the permeability based on the porosity using the Kozeny-Carman formula; A seepage velocity acquisition module, used for obtaining the gas seepage velocity based on the permeability by using Darcy's law; The leakage rate formula acquisition module is used to obtain the flange leakage rate formula based on the gas seepage velocity and the seepage cross-sectional area of ​​the flange sealing interface. The flange leakage rate formula is as follows: Q = u × S; Wherein, Q is the flange leakage rate; u is the gas seepage velocity; S is the seepage cross-sectional area of ​​the flange sealing interface; The leakage rate formula correction module is used to introduce damage parameters to correct the flange leakage rate, and obtain the following leakage rate formula that reflects the influence of flange sealing surface defects: Among them, α is the correction parameter added to consider the error between theory and practice; Collectively referred to as damage parameters, is the dimensionless damage area angle, is the average depth of damage to the sealing surface, is the radial average projection of the sealing surface damage; k is the permeability; k' is the permeability after porosity correction; R is the average radius of the flange sealing surface; μ is the viscosity coefficient of the sealing medium; Δp is the pressure difference between the sealing medium and the external environment; L is the contact width of the sealing surface.

8. The flange sealing surface damage assessment device based on leakage rate according to claim 7, characterized in that: The damage parameters It is divided into several levels, and the damage level of the flange sealing surface overall damage rating is the highest rating among the three damage parameters.

9. The flange sealing surface damage assessment device based on leakage rate according to claim 7, characterized in that: The formula correction unit comprises: The damage customization module is used to customize different degrees of pits or scratch damage on the flange sealing surface to obtain known damage parameters and Flange test piece; A leakage test module is used to control the leakage test of the flange specimen and measure the leakage rate Q under different damage degrees; Correction parameter acquisition module, used to measure the leakage rate Q and the corresponding damage parameter and Substituting into the leakage rate formula reflecting the influence of flange sealing surface defects, the value of the correction parameter α is obtained by using the least squares method for fitting.

10. The flange sealing surface damage assessment device based on leakage rate according to claim 6, characterized in that: The damage assessment unit is specifically used for: The Bayesian formula is used to correlate the leakage rate and the flange sealing surface damage level: In the above formula: Q represents the leakage rate; d represents the damage level of the flange sealing surface; P(d|Q) represents the probability that the damage level of the flange sealing surface is d under the condition that the leakage rate is Q, that is, the posterior probability; P(d) represents the probability that the damage level of the flange sealing surface is d, that is, the prior probability; P(Q) represents the probability of monitoring the leakage rate to be Q; P(Q|d) represents the probability that the leakage rate is Q when the damage level of the flange sealing surface is d, that is, the likelihood probability; According to the distribution of the posterior probability P(d|Q), the damage level corresponding to the posterior distribution of the damage parameter with the maximum probability is selected as the evaluation result of the damage of the flange sealing surface to be evaluated.

11. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

13. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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