Intelligent auxiliary system and method for pressure vessel inspection

Abstract

The invention discloses an intelligent auxiliary system and method for pressure vessel inspection, and relates to the technical field of pressure vessel inspection. According to the method, the sensor group is arranged at the key position of the pressure vessel, temperature, pressure, vibration and strain data are collected regularly, and the finite element analysis theory and the comprehensive evaluation model are combined, so that potential risks can be accurately identified, and equipment operation safety is ensured; through comprehensive analysis of stress damage, fatigue failure and corrosion damage, execution signals of different risk states are automatically generated, and the execution control module is triggered to carry out corresponding control operation; according to an evaluation result, automatic shutdown, operation parameter adjustment or emergency check starting are realized, so that the management efficiency is remarkably improved, and manual operation errors are reduced; through an intelligent emergency response mechanism, early warning is carried out before a dangerous state occurs, automatic measures are taken, further damage is avoided, and equipment faults and accidents are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure vessel inspection, and specifically provides an intelligent auxiliary system and method for pressure vessel inspection. Background Art

[0002] Pressure vessels are widely used in industries such as petroleum, chemical, power, and metallurgy, and are tasked with withstanding high-pressure gases or liquids. Due to the harsh working environment and the special functions of pressure vessels themselves, faults such as cracks, corrosion, and fatigue may occur during their use. If these problems are not detected and addressed in a timely manner, serious safety accidents may be triggered. Traditional pressure vessel inspections mainly rely on regular manual inspections and external visual inspections. Although this method can detect some obvious damages and faults, it also has many deficiencies.

[0003] First of all, traditional manual inspections rely on regular checks and cannot reflect the dynamic changes of pressure vessels during operation in real time. Especially in the case of sudden damage or equipment aging, faults cannot be detected in a timely manner, increasing the risk of accidents.

[0004] Secondly, existing pressure vessel inspection technologies often focus on a single dimension (such as visual inspection, thickness measurement, etc.), making it difficult to comprehensively evaluate the overall health status of the vessel. There is a lack of systematic multi-dimensional data analysis and dynamic modeling, and potential risks cannot be accurately predicted.

[0005] In view of the above problems, it is necessary to propose an intelligent auxiliary system and method for pressure vessel inspection. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems existing in the background art and propose an intelligent auxiliary system and method for pressure vessel inspection.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] In the first aspect, the present invention provides an intelligent auxiliary system for pressure vessel inspection, including a data acquisition and transmission module, a data analysis module, a pressure vessel status evaluation module, and an execution control module.

[0009] The data acquisition and transmission module collects the operation data of the pressure vessel in real time through a sensor group arranged at various key positions of the pressure vessel.

[0010] Among them, the key positions include: the inner wall of the top of the pressure vessel, the inner wall of the bottom of the pressure vessel, the inner wall of the side of the pressure vessel, the outer wall of the top of the pressure vessel, the outer wall of the bottom of the pressure vessel, the outer wall of the side of the pressure vessel, the outlet of the pressure vessel, the inlet of the pressure vessel, and the welded surface of the inner and outer walls of the pressure vessel.

[0011] Among them, the sensor group includes: a temperature sensor, a pressure sensor, a vibration sensor, and a strain gauge.

[0012] As a preferred embodiment of the present invention, the sensor group is accessed at preset time intervals to obtain sensor data at each key position, including the temperature Hi(t), pressure Pi(t), vibration amplitude Wi(t), and strain δi(t) at each key position i. Where i is the numbering symbol of the key position, and the specific values are i = 1, 2,..., 9; corresponding to the inner wall of the top of the pressure vessel, the inner wall of the bottom of the pressure vessel, the inner wall of the side of the pressure vessel, the outer wall of the top of the pressure vessel, the outer wall of the bottom of the pressure vessel, the outer wall of the side of the pressure vessel, the outlet of the pressure vessel, the inlet of the pressure vessel, and the welded surface of the inner and outer walls of the pressure vessel respectively.

[0013] The sensor data at each key position is transmitted to the data analysis module in real time through wireless and wired transmission methods to provide data support for subsequent processing.

[0014] The data analysis module obtains the sensor data at each key position sent by the data acquisition and transmission module, and conducts data analysis based on the finite element analysis theory and the material fatigue failure assessment theory to evaluate the overall monitoring status of the pressure vessel from three aspects: stress failure, fatigue failure, and corrosion damage.

[0015] As a preferred embodiment of the present invention, a three-dimensional stress model of the pressure vessel is established based on the finite element analysis theory, and the three-dimensional stress model is obtained according to the structural design drawings of the pressure vessel. Mesh division is performed in the three-dimensional stress model, and the pressure vessel structure is divided into small units with a length, width, and height of a preset value a for calculating pressure, stress, and strain on each small unit.

[0016] As a preferred embodiment of the present invention, in the three-dimensional stress model, it is assumed that the material used for the pressure vessel is a linear elastic material, that is, the stress-strain relationship of all small units is defined to follow Hooke's law: ; where , and are the normal stresses of the small unit in the x, y, and z directions respectively; where , and are the shear stresses of the small unit on the xy, yz, and xz planes respectively; where E is the Young's modulus of the pressure vessel material, G is the shear modulus of the pressure vessel material, and v is the Poisson's ratio of the pressure vessel material; where , and are the normal strains of the small unit in the x, y, and z directions respectively; where , and They are the shear strains of the small elements on the xy, yz, and xz planes respectively.

[0017] As a preferred embodiment of the present invention, stress propagation rules between individual small elements are formulated based on changes in the displacement and stress fields, and the stiffness matrix of each small element is established: ; where K is the stiffness matrix; where B is the displacement gradient matrix, which describes the relationship between stress and strain in each small element; where D is the elastic matrix of the pressure vessel material, which describes the relationship between stress and strain in each small element, ; where Ω is the volume domain of the element.

[0018] A finite element solver is established, and its propagation rules are limited by the equilibrium equation during the stress propagation process in the small elements, and the redistribution of internal forces and stresses caused by the displacement of the pressure vessel under the action of external pressure, vibration, and temperature is calculated. The equation of the finite element solver is: ; where K is the stiffness matrix, where U is the unknown nodal displacement vector, and where F is the external force;

[0019] As a preferred embodiment of the present invention, the sensor data at each key position is used as the input of the three-dimensional force model, and is applied to the small elements at the corresponding positions of the pressure vessel in the three-dimensional force model according to their respective corresponding key position identifiers, and the stress states of all small elements in the three-dimensional force model of the pressure vessel are obtained through the finite element solver and strain states . At each preset time interval, the three-dimensional force model is updated with newly collected sensor data, and the stress states and strain states of all small elements in the three-dimensional force model are dynamically updated.

[0020] As a preferred embodiment of the present invention, the actual stress states of each small element in the three-dimensional force model are obtained and visually output, color-coded according to the stress states of each small element, and the corresponding color values are matched according to the specific numerical values of the normal stress and shear stress of each small element to obtain the stress field distribution map of the entire pressure vessel.

[0021] As a preferred embodiment of the present invention, the stress and strain of each small element in the three-dimensional force model are obtained and input into the stress failure model, fatigue failure model, and corrosion damage model for further data analysis to analyze the location of the dangerous section and the usage status of the pressure vessel.

[0022] Among them, the stress failure model is specifically: through a preset formula calculate the Von Mises equivalent stress of each element; where σ1, σ2, and σ3 are the principal stresses of each small element; their specific numerical values are the stress tensor characteristic equation The solutions, where λ is the unknown eigenvalue to be obtained; the expansion of the stress tensor characteristic equation is a cubic equation, and the three solutions of λ are the principal stresses σ1, σ2, and σ3. If it is recognized that the von Mises equivalent stress σVM of a small element is greater than the yield strength of the pressure vessel material, it is determined that the stress of the small element exceeds the material yield strength and enters the plastic deformation stage, and the small element fails; if it is recognized that the von Mises equivalent stress σVM of a small element is less than or equal to the yield strength of the pressure vessel material, it is determined that the small element is within the elastic range, and the strain that occurs will be fully restored as the stress state improves, and the small element does not fail.

[0023] Calculate the von Mises equivalent stress of each small element and locate the small elements where the von Mises equivalent stress σVM is greater than the yield strength of the pressure vessel material.

[0024] Among them, the fatigue failure model is specifically: through a preset formula Calculate the Miners cycle constant of each small element ; where Aσ is the normal stress amplitude; Aσ = Aσ1, Aσ2,..., Aσmax; where Aσ1, Aσ2,..., Aσmax; are the specific reference values of the preset normal stress amplitude, and Aσmax is the maximum normal stress amplitude; where is the number of cycles at each large normal stress amplitude Aσ, and its specific value is based on the stress state in the normal stress , and in the maximum value obtained. Whenever it is recognized that the specific value is greater than the normal stress amplitude Aσ or less than -Aσ, then the number of cycles at this normal stress amplitude Aσ is increased by 1; where is the preset standard number of cycles at each normal stress amplitude Aσ;

[0025] Calculate the Miners cycle constant of each small element and locate the small elements where the Miners cycle constant is greater than 1.

[0026] As a preferred method of the present invention, record the maximum value , and in the normal stress calculated at each preset time interval. Taking the normal stress amplitudes Aσ = Aσ1, Aσ2, Aσ3 as the judgment thresholds, when it is recognized that transcends ±Aσ1 from a state less than Aσ or greater than -Aσ, the number of cycles Increase the specific value by 1; when When exceeding ±Aσ2 from a state less than Aσ2 or greater than -Aσ2, let the number of cycles Increase the specific value by 1; when When exceeding ±Aσ3 from a state less than Aσ3 or greater than -Aσ3, let the number of cycles Increase the specific value by 1; and so on.

[0027] Establish a corrosion damage model: ; where t is time; vc(t) is the corrosion rate at time t; where k is a preset corrosion constant, reflecting the corrosion characteristics of the pressure vessel material itself; where is the maximum principal stress of the small element obtained from the three-dimensional stress model at time t, where is the maximum value among the temperatures Hi(t) of each key position i collected at time t; where Q is a preset activation energy constant, reflecting the chemical reaction rate of the environment where the pressure vessel material is located; where R is a preset gas constant, reflecting the gas environment where the pressure vessel is located. Where is the calculated final corrosion depth.

[0028] Calculate the final corrosion depth of each small element, and locate the small elements with a final corrosion depth greater than the preset threshold.

[0029] The pressure vessel status evaluation module evaluates the overall usage status of the pressure vessel according to the analysis results of the stress failure model, fatigue failure model, and corrosion damage model in the data analysis module, and generates corresponding execution signals.

[0030] Obtain the specific positions of the small elements where the Von Mises equivalent stress σVM of each small element is greater than the yield strength of the pressure vessel material, and mark the small elements as stress failure units; obtain the specific positions of the small elements where the Miners cycle constant is greater than 1, and mark the small elements as fatigue failure units; obtain the specific positions of the small elements where the final corrosion depth is greater than the preset threshold, and mark the small elements as corrosion failure units.

[0031] Evaluate the overall usage status of the pressure vessel according to the following rules:

[0032] When the following conditions are met, it is determined that the usage status of the pressure vessel is normal, and a green identifier is assigned:

[0033] The Von Mises equivalent stress of all small elements is less than the material yield strength;

[0034] The Miners cycle constant of all small elements is less than 1;

[0035] The corrosion depth of all small units is less than the preset threshold.

[0036] When one of the following conditions is met, the usage status of the pressure vessel is determined to be a warning, and a yellow identifier is assigned:

[0037] The von Mises equivalent stress of N1 small units is greater than the yield strength;

[0038] The Miners cycle constant of N1 small units is greater than 1;

[0039] The corrosion depth of N1 small units is greater than the preset threshold.

[0040] When the following conditions are met simultaneously, the usage status of the pressure vessel is determined to be dangerous, and a red identifier is assigned

[0041] The von Mises equivalent stress of N2 small units is greater than the yield strength, resulting in plastic deformation;

[0042] The Miners cycle constant of N2 small units is greater than 1, entering the fatigue failure stage;

[0043] The corrosion depth of N2 small units is greater than the preset threshold, affecting the structural strength of the container.

[0044] Where N1 and N2 are preset judgment thresholds for the number of small units, and N2 is greater than N1.

[0045] Send the identification color of each pressure vessel to the execution control module.

[0046] The execution control module further triggers execution control operations based on the received identification colors of each pressure vessel to perform automated management operations and alarms, and takes corresponding control measures according to different risk states.

[0047] For pressure vessels with a green identifier, maintain the existing operating parameters such as pressure and temperature, make no adjustments, and do not trigger any emergency control instructions; continue to regularly collect sensor data and monitor the status changes of the pressure vessel in real time;

[0048] For pressure vessels with a yellow identifier, start the temperature regulating device and the pressure relief device, adjust the temperature and the working pressure of the small pressure vessel to avoid excessive stress concentration. Turn on the damping device to limit the vibration amplitude and reduce the occurrence of fatigue damage.

[0049] For pressure vessels with a red label, immediately perform an automatic shutdown operation to stop the operation of the pressure vessel and prevent further damage. Close the relevant valves to ensure that the pressure inside the pressure vessel drops to a safe range. Initiate an emergency inspection process, immediately notify the management personnel, and organize a professional team to conduct a detailed on-site inspection, especially for areas where stress failure, fatigue failure, or corrosion has occurred. Start a more stringent monitoring system to monitor all key parts 24 hours a day, reduce the data collection time interval of the pressure vessel to half of the preset time interval, and improve the accuracy and density of data monitoring.

[0050] In a second aspect, the present invention provides an intelligent auxiliary method for pressure vessel inspection, including the following steps:

[0051] Step 1: Data collection and transmission;

[0052] Real-time collect temperature, pressure, vibration, and strain data through a sensor group arranged at each key position of the pressure vessel.

[0053] Every preset time interval, the sensor data is uploaded to the data analysis module via wireless and wired means for subsequent processing.

[0054] Step 2: Data analysis and three-dimensional stress model establishment;

[0055] Process the transmitted data through the data analysis module, and analyze the stress, fatigue damage, and corrosion conditions of the pressure vessel based on the finite element analysis theory and the material fatigue failure assessment theory.

[0056] According to the structural drawings of the pressure vessel, divide the mesh using the finite element method and calculate the stress and strain states of each small unit. Use the collected sensor data as input to update the model.

[0057] Step 3: Pressure vessel condition assessment;

[0058] Calculate the Von Mises equivalent stress of each small unit through the stress failure model, identify the units with stress exceeding the yield strength, and determine whether failure has occurred.

[0059] Calculate the Miners cycle constant of each small unit through the fatigue failure model, evaluate the degree of fatigue damage, and identify the fatigue failure area.

[0060] Calculate the corrosion rate and corrosion depth through the corrosion damage model, and locate the corrosion damage area. Comprehensively evaluate the overall health status of the pressure vessel based on the above three aspects and generate an evaluation result.

[0061] Step 4: Execution signal generation and condition assessment;

[0062] When the following conditions are met, it is determined that the service state of the pressure vessel is normal, and a green label is assigned:

[0063] The von Mises equivalent stress of all small elements is less than the material yield strength;

[0064] The Miners cycle constant of all small elements is less than 1;

[0065] The corrosion depth of all small elements is less than the preset threshold.

[0066] When one of the following conditions is met, it is determined that the service state of the pressure vessel is in early warning, and a yellow label is assigned:

[0067] There are N1 small elements whose von Mises equivalent stress is greater than the yield strength;

[0068] There are N1 small elements whose Miners cycle constant is greater than 1;

[0069] There are N1 small elements whose corrosion depth is greater than the preset threshold.

[0070] When the following conditions are met simultaneously, it is determined that the service state of the pressure vessel is dangerous, and a red label is assigned

[0071] There are N2 small elements whose von Mises equivalent stress is greater than the yield strength, and plastic deformation occurs;

[0072] There are N2 small elements whose Miners cycle constant is greater than 1, entering the fatigue failure stage;

[0073] There are N2 small elements whose corrosion depth is greater than the preset threshold, affecting the structural strength of the container.

[0074] Where N1 and N2 are the preset judgment thresholds for the number of small elements, and N2 is greater than N1.

[0075] Generate an execution signal according to the classification and transmit it to the execution control module.

[0076] Step Five: Execution control response;

[0077] Perform specific operation and maintenance operations according to the state evaluation result and the execution signal;

[0078] For pressure vessels with green labels, maintain the existing operating parameters such as pressure and temperature, make no adjustments, and do not trigger any emergency control instructions; continue to regularly collect sensor data and monitor the state changes of the pressure vessel in real time;

[0079] For pressure vessels with yellow identification, start the temperature regulating device and pressure relief device, adjust the temperature and the working pressure of the small pressure vessel to avoid excessive stress concentration. Turn on the damping device to limit the vibration amplitude and reduce the occurrence of fatigue damage.

[0080] For pressure vessels with red identification, immediately perform an automatic shutdown operation to stop the operation of the pressure vessel and prevent further damage. Close the relevant valves to ensure that the pressure inside the pressure vessel drops to a safe range. Start an emergency inspection process, immediately notify the management personnel, and organize a professional team to conduct a detailed on-site inspection, especially for areas where stress failure, fatigue failure, or corrosion has occurred. Start a more rigorous monitoring system to monitor each key part for 24 hours, reduce the data acquisition time interval of the pressure vessel to half of the preset time interval, and improve the accuracy and density of data monitoring.

[0081] Compared with the prior art, the beneficial effects of the present invention are:

[0082] 1. By arranging a sensor group at key positions of the pressure vessel and regularly collecting temperature, pressure, vibration, and strain data, and uploading them to the data analysis module in real time, the present invention can continuously monitor the health status of the pressure vessel. This real-time monitoring enables the timely assessment of the usage status of the pressure vessel, reducing the lag and limitations of traditional manual inspections. Through a three-dimensional stress model based on the finite element analysis theory and a comprehensive assessment of fatigue failure, stress failure, and corrosion damage, potential risks can be accurately identified to ensure the safety of equipment operation;

[0083] 2. The pressure vessel status assessment module of the present invention combines a comprehensive model of stress failure, fatigue failure, and corrosion damage, and can automatically generate corresponding execution signals according to different risk states (such as green, yellow, red), triggering the execution control module to perform corresponding control operations. According to the assessment results, the system automatically responds, enabling operations such as automatic shutdown, adjustment of operating parameters, and start of emergency inspections, greatly improving the management efficiency of pressure vessels and reducing the risk of human operation errors;

[0084] 3. By combining real-time data collection and automatic assessment, the present invention can give early warnings and trigger corresponding safety measures before dangerous states occur. When the status of the pressure vessel reaches yellow or red, the system will not only issue a warning signal but also take measures to automatically adjust the temperature, pressure, or vibration, and even perform an automatic shutdown in case of emergency to prevent further damage to the container. This automated and intelligent emergency response mechanism can ensure the safe operation of the pressure vessel, reduce the probability of equipment failures and accidents, and thus guarantee personnel safety and equipment reliability. Brief Description of the Drawings

[0085] For the convenience of those skilled in the art to understand, the present invention will be further described below in conjunction with the accompanying drawings:

[0086] Figure 1 It is the system block diagram of the present invention;

[0087] Figure 2 It is the schematic diagram of the visual output of the three-dimensional stress model proposed in the embodiment of the present invention;

[0088] Figure 3 It is the schematic diagram of the relationship between the number of cycles and the maximum normal stress proposed in the embodiment of the present invention;

[0089] Figure 4 It is the method flow chart of the present invention. Specific embodiments

[0090] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0091] Please refer to Figure 1 As shown, an intelligent auxiliary system for pressure vessel inspection includes a data acquisition and transmission module, a data analysis module, a pressure vessel status evaluation module, and an execution control module.

[0092] The data acquisition and transmission module collects the operation data of the pressure vessel in real time through a sensor group arranged at each key position of the pressure vessel.

[0093] Among them, the key positions include: the inner wall of the top of the pressure vessel, the inner wall of the bottom of the pressure vessel, the inner wall of the side of the pressure vessel, the outer wall of the top of the pressure vessel, the outer wall of the bottom of the pressure vessel, the outer wall of the side of the pressure vessel, the outlet of the pressure vessel, the inlet of the pressure vessel, and the welded surface of the inner and outer walls of the pressure vessel.

[0094] Among them, the sensor group includes: a temperature sensor, a pressure sensor, a vibration sensor, and a strain gauge.

[0095] Furthermore, access the sensor group at preset time intervals to obtain the sensor data of each key position, including the temperature Hi(t), pressure Pi(t), vibration amplitude Wi(t), and strain δi(t) of each key position i. Where i is the numbering symbol of the key position, and the specific value is i = 1, 2,..., 9; corresponding to the inner wall of the top of the pressure vessel, the inner wall of the bottom of the pressure vessel, the inner wall of the side of the pressure vessel, the outer wall of the top of the pressure vessel, the outer wall of the bottom of the pressure vessel, the outer wall of the side of the pressure vessel, the outlet of the pressure vessel, the inlet of the pressure vessel, and the welded surface of the inner and outer walls of the pressure vessel respectively.

[0096] The sensor data at each key position is uploaded to the data analysis module in real time through wireless and wired transmission methods, providing data support for subsequent processing.

[0097] The data analysis module obtains the sensor data at each key position sent by the data acquisition and transmission module, and conducts data analysis based on the finite element analysis theory and the material fatigue failure assessment theory, and evaluates the overall monitoring status of the pressure vessel from three aspects: stress failure, fatigue failure and corrosion damage.

[0098] Furthermore, a three-dimensional stress model of the pressure vessel is established based on the finite element analysis theory, and the three-dimensional stress model is obtained according to the structural design drawings of the pressure vessel. Mesh division is carried out in the three-dimensional stress model, and the pressure vessel structure is divided into multiple small units with a length, width and height of a preset value a, which is used to calculate the pressure, stress and strain on each small unit.

[0099] Furthermore, in the three-dimensional stress model, it is assumed that the material used for the pressure vessel is a linear elastic material, that is, it is specified that the stress-strain relationship of all small units follows Hooke's law: ; where , and are the normal stresses of the small unit in the x, y and z directions respectively; where , and are the shear stresses of the small unit on the xy, yz and xz planes respectively; where E is the Young's modulus of the pressure vessel material, G is the shear modulus of the pressure vessel material, and v is the Poisson's ratio of the pressure vessel material; where , and are the normal strains of the small unit in the x, y and z directions respectively; where , and are the shear strains of the small unit on the xy, yz and xz planes respectively.

[0100] Furthermore, based on the changes in the displacement and stress fields, the stress propagation rules between each small unit are formulated, and the stiffness matrix of each small unit is established: ; where K is the stiffness matrix; where B is the displacement gradient matrix, which describes the relationship between the stress and strain in each small unit; where D is the elastic matrix of the pressure vessel material, which describes the relationship between the stress and strain in each small unit, ; where Ω is the volume domain of the unit.

[0101] A finite element solver is established. By using the equilibrium equation during the propagation of stress in small elements to define its propagation rules, the redistribution of internal forces and stresses caused by the displacements of the pressure vessel under external pressure, vibration, and temperature is calculated. The equation of the finite element solver is: where K is the stiffness matrix, U is the unknown nodal displacement vector, and F is the external force;

[0102] Furthermore, the sensor data at each key position is used as the input of the three-dimensional stress model. According to their respective corresponding key position identifiers, it is applied to the small elements at the corresponding positions of the pressure vessel in the three-dimensional stress model. The stress states of all small elements in the three-dimensional stress model of the pressure vessel are obtained through the finite element solver and strain states . At every preset time interval, the three-dimensional stress model is updated with newly acquired sensor data, and the stress states and strain states of all small elements in the three-dimensional stress model are dynamically updated.

[0103] Please refer to Figure 2 as shown. As shown in the visualization output schematic diagram of the three-dimensional stress model, the actual stress states of each small element in the three-dimensional stress model are obtained and visually output. Color markings are made according to the stress states of each small element. According to the specific numerical values of the normal stress and shear stress of each small element, the corresponding color values are matched to obtain the stress field distribution diagram of the entire pressure vessel.

[0104] Furthermore, the stresses and strains of each small element in the three-dimensional stress model are obtained and input into the stress failure model, fatigue failure model, and corrosion damage model for further data analysis to analyze the location of the dangerous section and the usage status of the pressure vessel.

[0105] Among them, the specific stress failure model is: By using the preset formula the Von Mises equivalent stress of each element is calculated; where, σ1, σ2, and σ3 are the principal stresses of each small element; their specific numerical values are the solutions of the stress tensor characteristic equation where λ is the unknown eigenvalue to be obtained; the expansion of the stress tensor characteristic equation is a cubic equation, and the three solutions of λ are the principal stresses σ1, σ2, and σ3. If it is identified that the Von Mises equivalent stress σVM of a small element is greater than the yield strength of the pressure vessel material, it is determined that the stress of this small element exceeds the material yield strength and enters the plastic deformation stage, and this small element fails; if it is identified that the Von Mises equivalent stress σVM of a small element is less than or equal to the yield strength of the pressure vessel material, it is determined that this small element is within the elastic range, and the strain that occurs will be completely restored as the stress state improves, and this small element does not fail.

[0106] Calculate the Von Mises equivalent stress of each small element, and locate the small elements where the Von Mises equivalent stress σVM is greater than the yield strength of the pressure vessel material.

[0107] Among them, the specific fatigue failure model is: through a preset formula Calculate the Miners cycle constant of each small element ; where Aσ is the normal stress amplitude; Aσ = Aσ1, Aσ2,..., Aσmax; where Aσ1, Aσ2,..., Aσmax; are the specific reference values of the preset normal stress amplitude, and Aσmax is the maximum normal stress amplitude; where is the number of cycles at each large normal stress amplitude Aσ, and its specific value is obtained according to the normal stress in the stress state , and the maximum value in is obtained. Whenever it is recognized that the specific value of is greater than the normal stress amplitude Aσ or less than -Aσ, then the number of cycles at this normal stress amplitude Aσ is increased by 1; where is the preset standard number of cycles at each normal stress amplitude Aσ;

[0108] Calculate the Miners cycle constant of each small element, and locate the small elements where the Miners cycle constant is greater than 1.

[0109] Please refer to Figure 3 as shown, as shown in the schematic diagram of the relationship between the number of cycles and the maximum normal stress, record the normal stress , and the maximum value in calculated at each preset time interval. Taking the normal stress amplitude Aσ = Aσ1, Aσ2, Aσ3 as the judgment threshold, when it is recognized that transcends ±Aσ1 from a state less than Aσ or greater than -Aσ, the number of cycles is increased by 1; when it is recognized that transcends ±Aσ2 from a state less than Aσ2 or greater than -Aσ2, the number of cycles is increased by 1; when it is recognized that transcends ±Aσ3 from a state less than Aσ3 or greater than -Aσ3, the number of cycles is increased by 1; taking Figure 2 as an example, = 22; = 13; = 8;

[0110] It should be noted that for metallic materials, under the condition of high-frequency cyclic loading, even if the cyclic load applied each time is far lower than its yield strength, it may still lead to the failure of the material structure. For example, during the process of repeatedly bending a wire, although the load applied each time is far lower than the yield strength of the wire, this repeated cyclic load can still cause damage to the structure of the wire.

[0111] It should be further noted that the significance of the Miners cycle constant is that it is a method for evaluating the fatigue life of materials under various stress amplitudes. By calculating the number of cycles of each small element under different stress amplitudes, the Miners' rule accumulates the contributions of each stress amplitude to the fatigue damage of the material, thereby predicting the cumulative damage situation of the material.

[0112] Establish a corrosion damage model: ; where t is time; vc(t) is the corrosion rate at time t; where k is a preset corrosion constant, reflecting the corrosion characteristics of the pressure vessel material itself; where is the maximum principal stress of the small element obtained from the three-dimensional stress model at time t, where is the maximum value among the temperatures Hi(t) of each key position i collected at time t; where Q is a preset activation energy constant, reflecting the chemical reaction rate of the environment where the pressure vessel material is located; where R is a preset gas constant, reflecting the gas environment where the pressure vessel is located. Where is the calculated final corrosion depth.

[0113] Calculate the final corrosion depth of each small element and locate the small elements whose final corrosion depth is greater than the preset threshold.

[0114] It should be noted that during use, the damage and rupture of a pressure vessel are not caused by a single factor, but are the result of the combined influence of multiple factors. Specifically, stress failure is one of the main factors that a pressure vessel may rupture or leak, and is used to evaluate the stress concentration of each part of the pressure vessel, especially in areas where the vessel wall is thinner. Fatigue failure is a phenomenon in which a pressure vessel gradually develops microcracks and minor damages under the action of long-term pressure changes, resulting in the overall pressure level of the pressure vessel being much lower than the conditions for pressure failure, but still experiencing structural failure. Corrosion damage will cause the reduction of the vessel wall thickness, thereby affecting the strength and safety of the vessel.

[0115] The pressure vessel status evaluation module evaluates the usage status of the entire pressure vessel based on the analysis results of the stress failure model, fatigue failure model, and corrosion damage model in the data analysis module, and generates corresponding execution signals.

[0116] Obtain the specific positions of the small elements where the von Mises equivalent stress σVM is greater than the yield strength of the pressure vessel material, and mark these small elements as stress failure elements; obtain the specific positions of the small elements where the Miners cycle constant is greater than 1, and mark these small elements as fatigue failure elements; obtain the specific positions of the small elements where the final corrosion depth is greater than the preset threshold, and mark these small elements as corrosion failure elements.

[0117] Evaluate the overall usage status of the pressure vessel according to the following rules:

[0118] When the following conditions are met, determine that the usage status of the pressure vessel is normal and assign a green label:

[0119] The von Mises equivalent stress of all small elements is less than the material yield strength;

[0120] The Miners cycle constant of all small elements is less than 1;

[0121] The corrosion depth of all small elements is less than the preset threshold.

[0122] When one of the following conditions is met, determine that the usage status of the pressure vessel is a warning and assign a yellow label:

[0123] There are N1 small elements whose von Mises equivalent stress is greater than the yield strength;

[0124] There are N1 small elements whose Miners cycle constant is greater than 1;

[0125] There are N1 small elements whose corrosion depth is greater than the preset threshold.

[0126] When the following conditions are met simultaneously, determine that the usage status of the pressure vessel is dangerous and assign a red label

[0127] There are N2 small elements whose von Mises equivalent stress is greater than the yield strength and plastic deformation occurs;

[0128] There are N2 small elements whose Miners cycle constant is greater than 1 and enter the fatigue failure stage;

[0129] There are N2 small elements whose corrosion depth is greater than the preset threshold and the structural strength of the container is affected.

[0130] Where N1 and N2 are preset judgment thresholds for the number of small elements, and N2 is greater than N1.

[0131] Send the identification color of each pressure vessel to the execution control module.

[0132] The execution control module further triggers execution control operations according to the identified colors of each pressure vessel to perform automated management operations and alarms, and takes corresponding control measures according to different risk states.

[0133] For pressure vessels with green identification, maintain the existing operating parameters such as pressure and temperature without any adjustment, and do not trigger any emergency control instructions; continue to regularly collect sensor data and monitor the state changes of the pressure vessel in real time;

[0134] For pressure vessels with yellow identification, start the temperature regulating device and the pressure relief device to adjust the temperature and the working pressure of the small pressure vessel to avoid excessive stress concentration. Turn on the damping device to limit the vibration amplitude and reduce the occurrence of fatigue damage.

[0135] For pressure vessels with red identification, immediately perform an automatic shutdown operation to stop the operation of the pressure vessel to prevent further damage. Close the relevant valves to ensure that the pressure inside the pressure vessel drops to a safe range. Start an emergency inspection process, immediately notify the management personnel, and organize a professional team to conduct a detailed on-site inspection, especially for areas where stress rupture, fatigue failure, or corrosion occur. Start a more stringent monitoring system to monitor each key part for 24 hours, reduce the data collection time interval of the pressure vessel to half of the preset time interval, and improve the accuracy and density of data monitoring.

[0136] Please refer to Figure 4 as shown, an intelligent auxiliary method for pressure vessel inspection includes the following steps:

[0137] Step 1: Data collection and transmission;

[0138] Real-time collect temperature, pressure, vibration, and strain data through a sensor group arranged at each key position of the pressure vessel.

[0139] Every preset time interval, the sensor data is uploaded to the data analysis module through wireless and wired methods for subsequent processing.

[0140] Step 2: Data analysis and three-dimensional stress model establishment;

[0141] Process the transmitted data through the data analysis module, and analyze the stress, fatigue damage, and corrosion conditions of the pressure vessel based on the finite element analysis theory and the material fatigue failure assessment theory.

[0142] According to the structural drawing of the pressure vessel, divide the mesh using the finite element method and calculate the stress and strain states of each small unit. Use the collected sensor data as input to update the model.

[0143] Step 3: Pressure vessel state assessment;

[0144] Calculate the Von Mises equivalent stress of each small element through the stress failure model, identify the elements whose stress exceeds the yield strength, and determine whether failure occurs.

[0145] Calculate the Miners cycle constant of each small element through the fatigue failure model, evaluate the degree of fatigue damage, and identify the fatigue failure area.

[0146] Calculate the corrosion rate and corrosion depth through the corrosion damage model, and locate the corrosion damage area. Comprehensively evaluate the overall health status of the pressure vessel based on these three aspects and generate an evaluation result.

[0147] Step Four: Execute signal generation and status evaluation;

[0148] When the following conditions are met, determine that the usage status of the pressure vessel is normal and assign a green label:

[0149] The Von Mises equivalent stress of all small elements is less than the material yield strength;

[0150] The Miners cycle constant of all small elements is less than 1;

[0151] The corrosion depth of all small elements is less than the preset threshold.

[0152] When one of the following conditions is met, determine that the usage status of the pressure vessel is under warning and assign a yellow label:

[0153] There are N1 small elements whose Von Mises equivalent stress is greater than the yield strength;

[0154] There are N1 small elements whose Miners cycle constant is greater than 1;

[0155] There are N1 small elements whose corrosion depth is greater than the preset threshold.

[0156] When the following conditions are met simultaneously, determine that the usage status of the pressure vessel is dangerous and assign a red label

[0157] There are N2 small elements whose Von Mises equivalent stress is greater than the yield strength and plastic deformation occurs;

[0158] There are N2 small elements whose Miners cycle constant is greater than 1 and enter the fatigue failure stage;

[0159] There are N2 small elements whose corrosion depth is greater than the preset threshold and affect the structural strength of the container.

[0160] Where N1 and N2 are preset judgment thresholds for the number of small elements, and N2 is greater than N1.

[0161] Generate an execution signal according to the classification and transmit it to the execution control module.

[0162] Step Five: Execution control response;

[0163] Perform specific operation and maintenance operations according to the status evaluation result and the execution signal;

[0164] For pressure vessels with a green label, maintain the existing operating parameters such as pressure and temperature without any adjustment and without triggering any emergency control instructions; continue to collect sensor data regularly and monitor the status change of the pressure vessel in real time;

[0165] For pressure vessels with a yellow label, start the temperature regulating device and the pressure relief device to adjust the temperature and the working pressure of the small pressure vessel to avoid excessive stress concentration. Turn on the damping device to limit the vibration amplitude and reduce the occurrence of fatigue damage.

[0166] For pressure vessels with a red label, immediately perform an automatic shutdown operation to stop the operation of the pressure vessel to prevent further damage. Close the relevant valves to ensure that the pressure inside the pressure vessel drops to a safe range. Start an emergency inspection process, immediately notify the management personnel, and organize a professional team to conduct a detailed on-site inspection, especially for areas where stress rupture, fatigue failure, or corrosion occur. Start a more stringent monitoring system to monitor each key part for 24 hours, reduce the data collection time interval of the pressure vessel to half of the preset time interval, and improve the accuracy and density of data monitoring.

[0167] It should be understood that the terms "including" and "comprising" used in the specification and claims of this disclosure indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0168] It should also be understood that the terms used in this disclosure specification are only for the purpose of describing specific embodiments and are not intended to limit this disclosure. As used in this disclosure specification and claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms. It should be further understood that the term "and / or" used in this disclosure specification and claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations;

[0169] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to only the specific embodiments. Obviously, many modifications and variations can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

[0170] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to only the specific embodiments. Obviously, many modifications and variations can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. An intelligent auxiliary system for pressure vessel inspection, comprising a data analysis module and a pressure vessel status assessment module, characterized in that: The data analysis module establishes a three-dimensional stress model of the pressure vessel based on the sensor data provided by the data acquisition module, and meshes the pressure vessel structure to obtain a number of small units; the stress state and strain state of each small unit are calculated through stress-strain analysis and the sensor data sent by the data acquisition and transmission module; the stress failure model, fatigue failure model and corrosion damage model are established through finite element analysis theory and fatigue failure assessment theory, and the stress, fatigue damage and corrosion damage of the pressure vessel are comprehensively analyzed in combination with the stress state and strain state of each small unit; The pressure vessel status assessment module combines the stress failure model, fatigue failure model and corrosion damage model to conduct a comprehensive analysis of the stress state and strain state of all small units to evaluate the overall health status of the pressure vessel; the Von Mises equivalent stress, Miners cycle constant and corrosion depth of each small unit are calculated through the stress state and strain state of each small unit to analyze the usage status of the pressure vessel; according to the analysis results, the pressure vessel is marked as different risk states, including green, yellow and red, and the corresponding execution signal is generated.

2. The intelligent auxiliary system for pressure vessel inspection according to claim 1 is characterized in that: It also includes a data acquisition and transmission module and an execution control module; The data acquisition and transmission module collects the operating data of the pressure vessel in real time through the sensor groups arranged at various key positions of the pressure vessel; Among them, the key positions include: the inner wall of the top of the pressure vessel, the inner wall of the bottom of the pressure vessel, the inner wall of the side of the pressure vessel, the outer wall of the top of the pressure vessel, the outer wall of the bottom of the pressure vessel, the outer wall of the side of the pressure vessel, the outlet of the pressure vessel, the inlet of the pressure vessel and the welding surface of the inner and outer walls of the pressure vessel; The sensor group includes: a temperature sensor, a pressure sensor, a vibration sensor and a strain gauge; The sensor group is accessed at preset time intervals to obtain sensor data of each key position, including temperature Hi(t), pressure Pi(t), vibration amplitude Wi(t) and strain δi(t) of each key position i; wherein i is the number of the key position, and the specific value is i=1, 2, ..., 9; corresponding to the inner wall of the top of the pressure vessel, the inner wall of the bottom of the pressure vessel, the inner wall of the side of the pressure vessel, the outer wall of the top of the pressure vessel, the outer wall of the bottom of the pressure vessel, the outer wall of the side of the pressure vessel, the outlet of the pressure vessel, the inlet of the pressure vessel and the welding surface of the inner and outer walls of the pressure vessel respectively; Upload sensor data from key locations to the data analysis module in real time through wireless and wired transmission; The execution control module triggers the execution control operation according to the identification color of each pressure vessel received to perform automated management operations and alarms, and takes corresponding control measures according to the green, yellow and red risk status.

3. The intelligent auxiliary system for pressure vessel inspection according to claim 1 is characterized in that: The specific process of establishing the three-dimensional stress model of the pressure vessel is as follows: Establish a three-dimensional stress model of the pressure vessel according to the structural design drawings of the pressure vessel, perform grid division in the three-dimensional stress model, divide the pressure vessel structure into a plurality of small units whose length, width and height are all preset values ​​a, and calculate pressure, stress and strain on each small unit; In the three-dimensional stress model, it is assumed that the material used for the pressure vessel is a linear elastic material, that is, the stress-strain relationship of all small units is limited to follow Hooke's law: ;in , and are the normal stresses of the small unit in the x, y and z directions respectively; , and are the shear stresses of the small unit on the xy, yz and xz planes respectively; E is the Young's modulus of the pressure vessel material, G is the shear modulus of the pressure vessel material, and v is the Poisson's ratio of the pressure vessel material; , and are the normal strains of the small unit in the x, y and z directions respectively; , and are the shear strains of the small unit in the xy, yz and xz planes respectively; The stress propagation rules between each small unit are formulated based on the changes in displacement and stress field.

4. The intelligent auxiliary system for pressure vessel inspection according to claim 3 is characterized in that: The stress propagation rules between each small unit are as follows: Establish the stiffness matrix of each small unit: ; K is the stiffness matrix; B is the displacement gradient matrix, which describes the relationship between stress and strain in each small unit; D is the elastic matrix of the pressure vessel material, which describes the relationship between stress and strain in each small unit, ; where Ω is the volume domain of the unit; A finite element solver is established to define the propagation rules of stress through the equilibrium equation in the process of stress propagation in small units, and to calculate the redistribution of internal force and stress caused by the displacement of the pressure vessel under the action of external pressure, vibration and temperature; the equation of the finite element solver is: ; Where K is the stiffness matrix, U is the unknown node displacement vector, and F is the external force; The sensor data at each key position is used as the input of the three-dimensional force model, and is applied to the small units at each corresponding position of the pressure vessel in the three-dimensional force model according to the corresponding key position number symbols. The stress state of all small units in the three-dimensional force model of the pressure vessel is obtained by the finite element solver. and strain state ; At every preset time interval, the three-dimensional force model is updated with the newly collected sensor data, and the stress state and strain state of all small units in the three-dimensional force model are dynamically updated.

5. The intelligent auxiliary system for pressure vessel inspection according to claim 1 is characterized in that: The stress failure model is specifically: pass Calculate the Von Mises equivalent stress of each unit; where σ1, σ2 and σ3 are the principal stresses of each small unit; their specific values ​​are the characteristic equation of the stress tensor , where λ is the unknown eigenvalue to be found; the expansion of the stress tensor characteristic equation is a cubic equation, where the three solutions of λ are the principal stresses σ1, σ2 and σ3; if it is identified that the Von Mises equivalent stress σVM of a small unit is greater than the yield strength of the pressure vessel material, it is determined that the stress of the small unit exceeds the yield strength of the material and enters the plastic deformation stage, and the small unit is damaged; if it is identified that the Von Mises equivalent stress σVM of a small unit is less than or equal to the yield strength of the pressure vessel material, it is determined that the small unit is within the elastic range, the strain will be completely recovered as the stress state improves, and the small unit is not damaged; Calculate the Von Mises equivalent stress of each small unit and locate the small units whose Von Mises equivalent stress σVM is greater than the yield strength of the pressure vessel material.

6. The intelligent auxiliary system for pressure vessel inspection according to claim 1, characterized in that: The fatigue failure model is specifically: By preset formula Calculate the Miners cycle constant for each small unit ; Where Aσ is the normal stress amplitude; Aσ=Aσ1, Aσ2, ..., Aσmax; Where Aσ1, Aσ2, ..., Aσmax; are specific reference values ​​of the preset normal stress amplitude, and Aσmax is the maximum normal stress amplitude; Where is the number of cycles at each large normal stress amplitude Aσ, and its specific value depends on the stress state Normal stress in , and The maximum value in Get, whenever you recognize When the specific value of is greater than the normal stress amplitude Aσ or less than -Aσ, let the number of cycles at the normal stress amplitude Aσ be The specific value of is increased by 1; is the preset number of Aσ standard cycles at each normal stress amplitude; Calculate the Miners cycle constant of each small unit and locate the small unit whose Miners cycle constant is greater than 1; Record the normal stress calculated at each preset time interval , and The maximum value in , taking the normal stress amplitude Aσ=Aσ1, Aσ2, Aσ3 as the judgment threshold, when the When the state exceeds ±Aσ1 from less than Aσ or greater than -Aσ, let the number of cycles The specific value of increases by 1; when it is recognized When the state exceeds ±Aσ2 from less than Aσ2 or greater than -Aσ2, let the number of cycles The specific value of increases by 1; when it is recognized When the state exceeds ±Aσ3 from less than Aσ3 or greater than -Aσ3, let the number of cycles The specific value of is increased by 1, and so on.

7. The intelligent auxiliary system for pressure vessel inspection according to claim 1, characterized in that: The corrosion damage model is specifically: By preset formula Calculate the final corrosion depth of each small unit; where t is time; vc(t) is the corrosion rate at time t; where k is the preset corrosion constant, reflecting the corrosion characteristics of the pressure vessel material itself; where is the maximum normal stress of the small unit obtained from the analysis of the three-dimensional force model at time t, where is the maximum value of the temperature Hi(t) of each key position i collected at time t; Q is the preset activation energy constant, which reflects the chemical reaction rate of the environment in which the pressure vessel material is located; R is the preset gas constant, which reflects the gas environment in which the pressure vessel is located; is the calculated final corrosion depth; The final corrosion depth of each small unit is calculated, and the small units whose final corrosion depth is greater than a preset threshold are located.

8. The intelligent auxiliary system for pressure vessel inspection according to claim 1 is characterized in that: The specific process of analyzing the results and marking the pressure vessel into different risk states is as follows: Obtain the specific location of each small unit whose Von Mises equivalent stress σVM is greater than the yield strength of the pressure vessel material, and mark the small unit as a stress damage unit; obtain the specific location of the small unit whose Miners cycle constant is greater than 1, and mark the small unit as a fatigue damage unit; obtain the specific location of the small unit whose final corrosion depth is greater than a preset threshold, and mark the small unit as a corrosion damage unit; The overall service status of the pressure vessel is evaluated according to the following rules: When the following conditions are met, the pressure vessel is considered to be in normal use and is given a green logo: The Von Mises equivalent stress of all small units is less than the material yield strength; The Miners cycle constant of all small units is less than 1; The corrosion depth of all small units is less than the preset threshold; When one of the following conditions is met, the use status of the pressure vessel is judged as a warning and a yellow mark is given: There are N1 small units whose Von Mises equivalent stress is greater than the yield strength; There are N1 small units whose Miners cycle constant is greater than 1; There are N1 small units whose corrosion depth is greater than the preset threshold; When the following conditions are met at the same time, the pressure vessel is judged to be in dangerous use and is marked red. There are N2 small units where the Von Mises equivalent stress is greater than the yield strength, and plastic deformation occurs; There are N2 small units with a Miners cycle constant greater than 1, entering the fatigue failure stage; There are N2 small units whose corrosion depth is greater than the preset threshold, affecting the structural strength of the container; N1 and N2 are preset small unit number judgment thresholds, and N2 is greater than N1.

9. The intelligent auxiliary system for pressure vessel inspection according to claim 2, characterized in that: The specific process of taking corresponding control measures according to the green, yellow and red risk status is: For pressure vessels with green labels, maintain the existing pressure and temperature operating parameters without making any adjustments or triggering any emergency control instructions; continue to collect sensor data regularly and monitor the status changes of the pressure vessels in real time; For pressure vessels with yellow markings, start the temperature regulating device and pressure relief device, adjust the temperature, reduce the working pressure of the pressure vessel, and start the damping device to limit the vibration amplitude; For pressure vessels with red marks, immediately perform automatic shutdown operations, stop the operation of the pressure vessels, and close related valves; Initiate the emergency inspection process, immediately notify the management personnel, organize a professional team to conduct a detailed on-site inspection, activate the monitoring system for areas where stress damage, fatigue failure or corrosion occurs, monitor each key part 24 hours a day, and reduce the data collection time interval for the pressure vessel to half of the preset time interval.

10. An intelligent auxiliary method for pressure vessel inspection, characterized in that An intelligent auxiliary system for pressure vessel inspection applied to any one of claims 1 to 9, comprising the following steps: Step 1: Data collection and transmission; The temperature, pressure, vibration and strain data are collected in real time by the sensor groups arranged at various key positions of the pressure vessel; at preset time intervals, the sensor data is uploaded to the data analysis module by wireless and wired means; Step 2: Data analysis and establishment of three-dimensional force model; The transmitted data is processed through the data analysis module, and the stress, fatigue damage and corrosion condition of the pressure vessel are analyzed based on the finite element analysis theory and material fatigue failure assessment theory. According to the structural drawings of the pressure vessel, the finite element method is used to divide the grid and calculate the stress and strain state of each small unit. The collected sensor data is used as input to update the model. Step 3: Pressure vessel status assessment; The Von Mises equivalent stress of each small unit is calculated through the stress failure model, and the units whose stress exceeds the yield strength are identified to determine whether failure occurs; The Miners cycle constant of each small unit is calculated through the fatigue failure model to evaluate the degree of fatigue damage and identify the fatigue failure area; The corrosion rate and corrosion depth are calculated through the corrosion damage model to locate the corrosion damage area; the overall health status of the pressure vessel is evaluated by combining the three factors to generate the evaluation results; Step 4: Execution signal generation and state evaluation; When the following conditions are met, the pressure vessel is considered to be in normal use and is given a green logo: The Von Mises equivalent stress of all small units is less than the material yield strength; The Miners cycle constant of all small units is less than 1; The corrosion depth of all small units is less than the preset threshold; When one of the following conditions is met, the use status of the pressure vessel is judged as a warning and a yellow mark is given: There are N1 small units whose Von Mises equivalent stress is greater than the yield strength; There are N1 small units whose Miners cycle constant is greater than 1; There are N1 small units whose corrosion depth is greater than the preset threshold; When the following conditions are met at the same time, the pressure vessel is judged to be in dangerous use and is marked red. There are N2 small units where the Von Mises equivalent stress is greater than the yield strength, and plastic deformation occurs; There are N2 small units with a Miners cycle constant greater than 1, entering the fatigue failure stage; There are N2 small units whose corrosion depth is greater than the preset threshold, affecting the structural strength of the container; Where N1 and N2 are preset small unit number judgment thresholds, and N2 is greater than N1; Generate an execution signal based on the classification and transmit it to the execution control module; Step 5: Execute control response; Execute specific operation and maintenance operations based on status assessment results and execution signals; For pressure vessels with green labels, maintain the existing pressure and temperature operating parameters without making any adjustments or triggering any emergency control instructions; continue to collect sensor data regularly and monitor the status changes of the pressure vessels in real time; For pressure vessels with yellow markings, start the temperature regulating device and pressure relief device, adjust the temperature, the working pressure of the small pressure vessel, and start the damping device to limit the vibration amplitude; For pressure vessels with red markings, automatic shutdown operations will be performed immediately to stop the operation of the pressure vessel, close relevant valves, start the emergency inspection process, immediately notify the management personnel, organize a professional team to conduct a detailed on-site inspection, and start the monitoring system for areas where stress damage, fatigue failure or corrosion occurs. All key parts will be monitored 24 hours a day, and the data collection time interval for the pressure vessel will be reduced to half of the preset time interval.

Images