Method and device for determining health status of storage tank siding

Abstract

The present application discloses a method and device for determining the health status of a tank siding, wherein the method comprises: obtaining a preset maximum stress calculation model for the tank, wherein the maximum stress calculation model for the tank is obtained by assigning solution conditions to a finite element model of the tank and then performing fitting processing; obtaining tank information and siding corrosion information; calculating a health status index of the tank based on the safety factor of the tank, and based on the maximum stress calculation model for the tank, the tank information, and the siding corrosion information; determining the risk level of the tank based on the correspondence between the preset health status index and the risk level, wherein the risk level is used to determine the current health status of the tank. The method and device for determining the health status of a tank siding disclosed in the present application can determine the current health status of the tank, help to reasonably predict the operating load-bearing capacity of the tank, and ensure the safety of the tank operation.

Description

Technical Field

[0001] The present application relates to the field of petrochemical technology, and in particular to a method and device for determining the health status of a storage tank wall panel. Background Art

[0002] Steel storage tanks are typically thin-walled metal structures. Tank siding is susceptible to corrosion from both the external environment and internal media, and the loads it bears are relatively complex, making it a critical component of the entire tank. Analysis of numerous tank engineering accidents both domestically and internationally indicates that siding corrosion is a primary cause of tank failure. Therefore, studying the strength and stability of large steel tanks under siding corrosion and predicting their operational load-bearing capacity are of theoretical, economic, and practical significance for ensuring the long-term safe and stable operation of tanks.

[0003] Currently, tank siding corrosion detection primarily relies on ultrasonic thickness measurement to assess the current corrosion status. This is then combined with relevant regulations in the standard to determine whether the plate requires repair welding or replacement. Safety assessments of tank siding corrosion primarily refer to the standard. The key steps include determining the corrosion location and depth through ultrasonic thickness measurement, determining the appropriate ring plate thickness based on the corrosion location, and finally assessing the tank siding according to GB / T30578-2014, "Risk-Based Inspection and Evaluation of Atmospheric Pressure Storage Tanks." This regulation states: "The average thickness of the tank siding shall not be less than the sum of the minimum calculated thickness of the ring plate and the corrosion allowance within the next inspection period. If the depth of scattered pitting on the tank siding exceeds the maximum allowable value specified in the standard, repair or replacement shall be performed." Simply put, ultrasonic thickness measurement is used to determine the corrosion status of ring plates of varying thicknesses and then compared with the allowable values ​​in the corresponding standard. If the value exceeds the maximum value specified in the standard, the tank is deemed to be in a failed state and must be immediately shut down for maintenance. If the value does not exceed the standard, the tank is deemed to be safe for continued operation.

[0004] However, the aforementioned safety assessment method for corroded tank siding has the following drawbacks: Existing evaluation standards only specify critical values ​​for allowable corrosion depths. Therefore, they can only assess the health of a tank in a given state, but cannot predict its future health. Due to the long intervals between maintenance cycles, it is difficult for staff to determine whether tanks that have not yet experienced a failure need to be repaired during the current maintenance cycle. Furthermore, the maximum allowable corrosion depth varies for sidings of varying thickness, requiring reference to different standards for comparison, a complex and non-universal process. Summary of the Invention

[0005] In view of this, the present application provides a method and device for determining the health status of a tank siding, which can determine the current health status of the tank, help to reasonably predict the operating load capacity of the tank, and ensure the safety of the tank operation.

[0006] This application specifically adopts the following technical solutions:

[0007] One aspect of the present application is to provide a method for determining the health status of a tank wall panel, the method comprising:

[0008] Acquire storage tank information and wall plate corrosion information, wherein the storage tank information includes material mechanical parameters, size parameters, and medium parameters in the storage tank, and the wall plate corrosion information includes the location and corrosion depth of each corrosion point;

[0009] Obtaining a preset maximum stress calculation model for the storage tank, wherein the maximum stress calculation model for the storage tank is obtained by assigning solution conditions to a finite element model of the storage tank and then performing a fitting process, wherein the solution conditions include load conditions and boundary conditions;

[0010] Calculating a health status index of the storage tank according to the safety factor of the storage tank, the maximum stress calculation model of the storage tank, the storage tank information, and the wall plate corrosion information;

[0011] The risk level of the storage tank is determined according to a preset correspondence between the health status index and the risk level, and the risk level is used to determine the current health status of the storage tank.

[0012] Preferably, the step of obtaining a preset storage tank maximum stress calculation model includes:

[0013] Get the maximum allowable corrosion depth t of the tank wall max , 0 <t max ≤3.5mm;

[0014] Using the dichotomy method in 0~t max Set N groups of different corrosion depths, N ≥ 8;

[0015] Constructing a geometric model of the storage tank based on the storage tank information and the wall plate corrosion information;

[0016] The geometric model is discretized using a finite element method, and the solution condition is applied to obtain the maximum stress of the storage tank corresponding to the N groups of different corrosion depths;

[0017] Fitting the relationship between the corrosion depth and the maximum stress of the storage tank to obtain a calculation model for the maximum stress of the storage tank;

[0018] Obtain a maximum stress calculation model for the storage tank.

[0019] Preferably, the maximum allowable corrosion depth t of the tank wall is obtained. max ,include:

[0020] The maximum allowable corrosion depth t is obtained according to the following relationship max :

[0021] t max =0.35T

[0022] Where, T is the thickness of the tank wall;

[0023] When t calculated by the above relationship max When it is greater than 3.5 mm, let t max =3.5mm.

[0024] Preferably, fitting the relationship between the corrosion depth and the maximum stress of the storage tank to obtain the maximum stress calculation model of the storage tank includes:

[0025] A stress-corrosion function is obtained by fitting the N groups of different corrosion depths and their corresponding maximum stresses of the storage tank;

[0026] Establishing a correction coefficient to correct the stress-corrosion function and obtain the maximum stress calculation model of the storage tank,

[0027] The expression of the maximum stress calculation model of the storage tank is:

[0028]

[0029] Wherein, σ is the maximum stress value of the tank, Pa; C is the correction coefficient; H is the height of the tank, m; D is the inner diameter of the tank, m; T is the wall thickness, m; t is the corrosion depth, m; ρ is the medium density, kg / m 3 ; g is the acceleration due to gravity, N / kg;

[0030] The correction coefficient is obtained by the following relationship:

[0031] C=C H ·C D ·C t

[0032] C H =1.15×10 3

[0033] C D =17.25 / D0

[0034] C t =T / (11.76-0.02|t|)

[0035] Among them, CH is the altitude correction factor; C D is the inner diameter correction parameter, 1 / m; D0 is the reference inner diameter, take D0 = 30m; C t is the corrosion correction parameter, m.

[0036] Preferably, the calculating of the health status index of the storage tank according to the safety factor of the storage tank, and based on the maximum stress calculation model of the storage tank, the storage tank information and the tank wall corrosion information includes:

[0037] The health status index of the storage tank is calculated according to the following relationship:

[0038]

[0039] Where Q is the health index; σ is the maximum stress value of the tank, Pa; R eL is the yield strength, Pa; K is the safety factor, take K = 1.2.

[0040] Preferably, determining the risk level of the storage tank according to a preset correspondence between the health status index and the risk level includes:

[0041] When the health status index is less than 0.6283, the risk level of the storage tank is determined to be excellent;

[0042] When the health status index is not less than 0.6283 and not greater than 0.85146, the risk level of the storage tank is determined to be medium;

[0043] When the health status index is greater than 0.85146, the risk level of the storage tank is determined to be poor.

[0044] Preferably, after determining the risk level of the storage tank, the method further comprises:

[0045] Tank handling measures are determined based on the risk level, and the tank handling measures include immediate maintenance, intensive monitoring, and normal use.

[0046] Preferably, determining the tank treatment measures based on the risk level includes:

[0047] When the risk level of the storage tank is poor, immediately maintain the storage tank;

[0048] When the risk level of the storage tank is medium, the storage tank is monitored intensively;

[0049] When the risk level of the storage tank is excellent, the storage tank is used normally.

[0050] Another aspect of the present application is to provide a device for determining the health status of a tank wall panel, the device comprising:

[0051] An acquisition module is used to acquire storage tank information and wall plate corrosion information, wherein the storage tank information includes material mechanical parameters, size parameters and medium parameters in the storage tank, and the wall plate corrosion information includes the location and corrosion depth of each corrosion point;

[0052] The acquisition module is further configured to acquire a preset maximum stress calculation model for the storage tank, wherein the maximum stress calculation model for the storage tank is obtained by assigning solution conditions to a finite element model of the storage tank and then performing a fitting process, wherein the solution conditions include load conditions and boundary conditions;

[0053] a calculation module, configured to calculate a health status index of the storage tank based on the safety factor of the storage tank, the maximum stress calculation model of the storage tank, the storage tank information, and the wall plate corrosion information;

[0054] The determination module is used to determine the risk level of the storage tank according to a preset correspondence between the health status index and the risk level, and the risk level is used to determine the health status of the storage tank.

[0055] Preferably, the determining module is further configured to:

[0056] Tank handling measures are determined based on the risk level, and the tank handling measures include immediate maintenance, intensive monitoring, and normal use.

[0057] The beneficial effects of the embodiments of the present application are at least:

[0058] In the embodiment of the present application, the tank information and the tank wall corrosion information are obtained, which can reflect the current corrosion status of the tank; then, based on the two pieces of information obtained, as well as the preset tank maximum stress calculation model and the tank safety factor, the tank health status index can be calculated; next, by substituting the tank health status index into the preset correspondence between the status index and the risk level, the risk level corresponding to the health status index can be obtained, and then the current health status of the tank can be determined according to the risk level. The method for determining the health status of the tank wall provided in the embodiment of the present application takes into account the current corrosion status of the tank, the maximum stress status of the tank, and the corresponding safety factor. These parameters are highly referenceable for judging the health status of the tank. Therefore, the tank risk level obtained on this basis is relatively accurate, can effectively reflect the current health status of the tank, and help staff reasonably predict the operating carrying capacity of the tank, thereby ensuring the safety of the tank operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0060] Figure 1 This is a flow chart of a method for determining the health status of a tank siding provided in an embodiment of the present application;

[0061] Figure 2 This is a flow chart of another method for determining the health status of a tank siding provided in an embodiment of the present application;

[0062] Figure 3 The corresponding relationship between the health status index and the risk index provided in the embodiment of the present application;

[0063] Figure 4 This is a diagram of metal magnetic memory detection results provided by an embodiment of the present application;

[0064] Figure 5 This is a device for determining the health status of a tank wall panel provided in an embodiment of the present application. DETAILED DESCRIPTION

[0065] In order to make the technical solutions and advantages of the present application clearer, the implementation methods of the present application will be described in further detail below with reference to the accompanying drawings.

[0066] An embodiment of the present application provides a method for determining the health status of a tank wall panel. The execution subject of the method may be a computer device, which may be a terminal, a server, a processor, or any type of data processing device with data processing capabilities.

[0067] like Figure 1 As shown, the method for determining the health status of a tank wall panel provided in an embodiment of the present application includes the following steps:

[0068] S101. Acquire storage tank information and wall plate corrosion information. The storage tank information includes material mechanical parameters, size parameters, and medium parameters in the tank. The wall plate corrosion information includes the location and corrosion depth of each corrosion point.

[0069] S102, obtaining a preset maximum stress calculation model for the storage tank, wherein the maximum stress calculation model for the storage tank is obtained by assigning solution conditions to the finite element model of the storage tank and then performing a fitting process, wherein the solution conditions include load conditions and boundary conditions;

[0070] S103. Calculate the health status index of the storage tank based on the safety factor of the storage tank, the maximum stress calculation model of the storage tank, the storage tank information, and the wall plate corrosion information;

[0071] S104. Determine the risk level of the storage tank according to a preset correspondence between the health status index and the risk level. The risk level is used to determine the current health status of the storage tank.

[0072] In summary, the method for determining the health status of the tank wall plate provided in the embodiment of the present application obtains tank information and tank wall plate corrosion information, which can reflect the current corrosion condition of the tank; then based on the two pieces of information obtained, as well as the preset tank maximum stress calculation model and the tank safety factor, the health status index of the tank can be calculated; next, by substituting the health status index of the tank into the preset correspondence between the status index and the risk level, the risk level corresponding to the health status index can be obtained, and then the current health status of the tank can be determined according to the risk level. The method for determining the health status of the tank wall plate provided in the embodiment of the present application takes into account the current corrosion condition of the tank, the maximum stress condition of the tank, and the corresponding safety factor. These parameters are highly referenceable for judging the health status of the tank. Therefore, the tank risk level obtained on this basis is relatively accurate, can effectively reflect the current health status of the tank, and help staff reasonably predict the operating carrying capacity of the tank, thereby ensuring the safety of the tank operation.

[0073] Figure 2 This is a flowchart of another method for determining the health status of a tank wall provided by an embodiment of the present application. The method can be executed by a computer device, which can be a terminal, a server, a processor, or any processing module with data processing capabilities. This embodiment of the present application takes the terminal as an example to describe the method in detail. Figure 2 As shown, the method may include the following steps:

[0074] Step 201: Obtain storage tank information and wall plate corrosion information.

[0075] Tank siding is susceptible to corrosion from both the external environment and internal media, and it also bears relatively complex loads, making it a critical component of the entire tank. Corrosion in the siding can easily lead to stress concentration, potentially damaging the tank. Therefore, when determining the health of a tank siding, the primary consideration is its corrosion status.

[0076] For example, tank information and siding corrosion information can be obtained through data collection and on-site surveys. Tank information can include material mechanical parameters (e.g., elastic modulus, yield strength, etc.), dimensional parameters (e.g., inner diameter, height, etc.), and medium parameters (e.g., density, liquid level, etc.). These parameters are basic tank parameters and can be obtained by collecting tank data. Siding corrosion information can include the location and depth of each corrosion point and can be obtained through ultrasonic thickness measurement.

[0077] In some embodiments of the present application, after the above information is acquired, the above information of the storage tank may also be stored in the terminal.

[0078] Step 202: Obtain a preset storage tank maximum stress calculation model.

[0079] Corrosion in tank siding can easily lead to stress concentration, which can cause tank damage. Therefore, it's necessary to measure tank stress and determine the maximum stress the tank can withstand. Based on this, a universally applicable maximum tank stress calculation model can be pre-established and stored in the terminal.

[0080] The process of establishing the maximum stress calculation model of the storage tank includes the following steps:

[0081] Step 301: Obtain the maximum allowable corrosion depth t of the tank wall max .

[0082] In the embodiment of the present application, the maximum allowable corrosion depth of the tank wall is t max It can be obtained through the following relationship:

[0083] t max =0.35T

[0084] Where T is the thickness of the tank wall.

[0085] It should be noted that according to the Chinese national standard "GB / T 30578-2014 Risk-Based Inspection and Evaluation of Atmospheric Pressure Storage Tanks," "the average thickness of the tank wall shall not be less than the sum of the minimum calculated thickness of the wall and the corrosion allowance within the next inspection period. If the depth of scattered pitting on the tank wall exceeds the maximum allowable value specified in the standard, it should be repaired or replaced." The allowable pitting depths for tank wall panels specified in the standard are shown in Table 1 below.

[0086] Table 1 Permissible pitting depth of tank wall panels (mm)

[0087] Steel plate thickness Allowable pitting depth Steel plate thickness Allowable pitting depth 5 1.8 8 2.8 6 2.2 9 3.2 7 2.5 ≥10 3.5

[0088] It can be seen that when the thickness of the steel plate is not less than 10 mm, the allowable pitting depth is 3.5 mm. In order to comply with the provisions of the Chinese national standard, in the embodiment of the present application, when the maximum allowable corrosion depth t is calculated by the above relationship, max When it is greater than 3.5 mm, let t max =3.5mm, that is, t max The value range is 0 <t max ≤3.5mm.

[0089] Step 302: Use the dichotomy method to calculate themax N groups of different corrosion depths are set.

[0090] In order to ensure the fitting accuracy of the maximum stress calculation model of the storage tank, the value of N is usually not less than 8. Taking N = 8 as an example, then in 0 ~ t max You can set t max 、 These 8 groups have different corrosion depths.

[0091] Step 303: Construct a geometric model of the storage tank based on the storage tank information and the wall plate corrosion information.

[0092] The terminal can call upon the tank information and panel corrosion information acquired in step 201, and then construct a geometric model of the tank based on these two pieces of information. The geometric model of the tank includes multiple panels and multiple corrosion points, each of the multiple panels corresponding to an actual panel in the tank, and each of the multiple corrosion points corresponding to an actual corrosion point on the tank. The material mechanical parameters and dimensional parameters of each panel are the same as those of the corresponding actual panel, and the corrosion location and depth of each corrosion point are the same as those of the corresponding actual corrosion point.

[0093] Step 304: discretize the geometric model using the finite element method and apply solution conditions to obtain the maximum stress of the storage tank corresponding to N groups of different corrosion depths.

[0094] The tank geometry was imported into finite element analysis software, meshed, and constructed into a finite element model. Solution conditions were applied to the finite element model to obtain eight sets of maximum tank stresses corresponding to the eight corrosion depths mentioned above. These solution conditions included load and boundary conditions.

[0095] Step 305: Fitting is performed based on N groups of different corrosion depths and their corresponding maximum stresses of the storage tank to obtain a stress-corrosion function.

[0096] For example, the least squares method can be used to fit the data of 8 sets of corrosion depths and their corresponding maximum stresses of the storage tank to obtain a stress-corrosion function. The fitting method can also be a polynomial fitting method, an interpolation method, etc.

[0097] The expression of the fitted stress-corrosion function is:

[0098]

[0099] Where σ is the maximum stress value of the tank, Pa; H is the height of the tank, m; D is the inner diameter of the tank, m; T is the wall thickness, m; t is the corrosion depth, m; ρ is the medium density, kg / m3 ; g is the acceleration due to gravity, N / kg.

[0100] In order to further improve the accuracy of data fitting, in a possible design, the following step 306 may also be performed.

[0101] Step 306: Establish a correction coefficient to correct the stress-corrosion function.

[0102] Taking into account the actual tank placement environment, the correction of the stress-corrosion function can include correction of the tank information and the wall plate corrosion information. Specifically, it can include correction of the tank height, the tank inner diameter and the corrosion depth. After a large amount of data fitting, the correction coefficient can be obtained through the following relationship:

[0103] C=C H ·C D ·C t

[0104] C H =1.15×10 3

[0105] C D =17.25 / D0

[0106] C t =T / (11.76-0.02|t|)

[0107] Where C is the correction coefficient; C H is the altitude correction factor; C D is the inner diameter correction parameter, 1 / m; D0 is the reference inner diameter, take D0 = 30m; C t is the corrosion correction parameter, m.

[0108] Accordingly, the functional expression of the modified tank maximum stress calculation model is:

[0109]

[0110] Wherein, σ is the maximum stress value of the tank, Pa; C is the correction coefficient; H is the height of the tank, m; D is the inner diameter of the tank, m; T is the wall thickness, m; t is the corrosion depth, m; ρ is the medium density, kg / m 3 ; g is the acceleration due to gravity, N / kg.

[0111] The tank maximum stress calculation model obtained in the embodiment of the present application has good accuracy and adaptability. It can be used to calculate the tank maximum stress corresponding to different corrosion depths, thereby simplifying the process of obtaining the tank maximum stress. In the embodiment of the present application, after obtaining the tank maximum stress calculation model, the model can be stored in the terminal so that it can be called upon at any time when the tank maximum stress calculation is needed.

[0112] In some embodiments of the present application, the tank maximum stress calculation model may be verified by collecting other corrosion depth data and tank maximum stress data to continuously update and optimize the tank maximum stress calculation model.

[0113] Step 203: Calculate the health status index of the storage tank according to the safety factor of the storage tank, the storage tank information, the wall plate corrosion information, and the storage tank maximum stress calculation model.

[0114] The health status index of the tank can be calculated using the following relationship:

[0115]

[0116] Where Q is the health index; σ is the maximum stress value of the tank, Pa; R eL is the yield strength, Pa; K is the safety factor, usually taking the empirical value of 1.2, that is, K=1.2.

[0117] Step 204: Determine the risk level of the storage tank based on the preset correspondence between the health status index and the risk level.

[0118] In the embodiment of the present application, the risk coefficients of a large number of storage tanks can be determined by risk analysis of a large number of storage tank projects at home and abroad, and then the relationship curve between the health status index and the risk coefficient can be established by fitting the health status index and the risk coefficient. The relationship curve between the health status index and the risk coefficient established in the embodiment of the present application is as follows: Figure 3 As shown in , the greater the risk coefficient, the greater the health status index.

[0119] Based on the tank's health status under the corresponding risk factor, the risk factor can be divided into three risk levels: 0-30%, 30%-80%, and 80%-100%, corresponding to excellent, medium, and poor, respectively. This provides a corresponding relationship between the health status index and the risk level, which is stored in the terminal.

[0120] Based on this corresponding relationship curve, it can be determined that

[0121] When the health status index is less than 0.6283, the risk level of the tank is determined to be excellent;

[0122] When the health status index is not less than 0.6283 and not greater than 0.85146, the risk level of the storage tank is determined to be medium;

[0123] When the health status index is greater than 0.85146, the risk level of the tank is determined to be poor.

[0124] Step 205: Determine storage tank treatment measures based on the risk level.

[0125] The risk level reflects the health status of the tank. Tank maintenance personnel can perform different treatment measures on the tank according to the determined risk level to eliminate safety hazards.

[0126] In some embodiments of the present application, the treatment measures may include: immediate maintenance, focused monitoring, and normal use.

[0127] When the risk level of a storage tank is poor, it means that the tank has been severely corroded, its health status is poor, and its risk resistance is poor. The tank needs to be maintained immediately to ensure safe operation.

[0128] When the risk level of a storage tank is medium, it means that corrosion has occurred on the tank, but the corrosion will not affect the normal operation of the tank for the time being and is still within the controllable range. Therefore, the tank needs to be monitored closely and maintained regularly.

[0129] When the risk level of a storage tank is excellent, it means that the tank is currently in a healthy state and can be used normally.

[0130] In addition, maintenance personnel can also make adaptive adjustments to the maintenance cycle of each tank based on the tank's risk level. For example, a tank with a poor risk level will be repaired in the current maintenance cycle and its risk level will be reassessed in the next maintenance cycle. A tank with a medium risk level will not be repaired in the current cycle and its risk level will be reassessed in the next maintenance cycle. A tank with an excellent risk level will not be repaired in either the current or next maintenance cycle and its risk level will be reassessed in the next maintenance cycle. This shortens the maintenance workload and improves maintenance efficiency.

[0131] For example, Chongqing Station has eight 10,000-cubic-meter internal floating roof tanks, two 2,000-cubic-meter dome tanks, three 1,000-cubic-meter dome tanks, and several smaller storage tanks. Four of these 10,000-cubic-meter internal floating roof tanks, G31201, G31202, G31203, and G31204, were converted from existing external floating roof tanks. They have been in operation for over 10 years and have all experienced varying degrees of siding corrosion. The following uses Chongqing Station's 10,000-cubic-meter internal floating roof tank G31201 as an example to provide a detailed illustration of the method for determining the health status of the tank siding provided in this embodiment and the use of the aforementioned formula:

[0132] (1) Collect and obtain the parameters of the G31201 tank: inner diameter of 30m, height of about 15.5m, liquid level height during operation of 2-14.8m, elastic modulus of 210GPa, yield strength of 345MPa, the storage medium in the tank is diesel, and the density of diesel is 830kg / m 3 .

[0133] (2) Survey site, using ultrasonic thickness measurement technology to detect corrosion depth and determine the thickness of the tank wall where each corrosion point is located. The survey results are shown in Table 2.

[0134] Table 2 Corrosion depth of tank wall (mm)

[0135]

[0136] According to the relevant design data, the original design thickness of the first wall panel was 16 mm. Combined with the test data in Table 2, it can be seen that the first wall panel of the tank has been corroded, with the maximum corrosion depth reaching 2.9 mm.

[0137] (3) Calculate the correction factor and the maximum stress value of the tank.

[0138] C H =1.15×10 3

[0139]

[0140] C=C H ·C D ·C t =1.15×10 3 ×0.575×1.37×10 -3 =0.91

[0141]

[0142] (4) Calculate the health status index Q of the storage tank.

[0143]

[0144] When Q=0.873, the risk level corresponding to the tank is determined to be poor, and the tank should be repaired immediately.

[0145] (5) The results are verified based on metal magnetic memory detection technology.

[0146] Use a metal magnetic memory detector to perform metal magnetic memory detection at the corrosion location. The test results are as follows: Figure 4 shown.

[0147] This metal magnetic memory detector has multiple channels, and the odd and even channels represent the tangential and normal components of the magnetic field intensity respectively. When the test passes through the stress concentration area, the curve will have corresponding peaks or sudden changes. Figure 4 The curves at the top represent the magnetic field intensity, and the curves at the bottom represent the magnetic field gradient. The magnetic field gradient refers to the slope of the magnetic field intensity curve, and the magnetic field gradient value is a key indicator for evaluating the degree of stress concentration.

[0148] See also Figure 4 The magnetic field gradient reaches a peak near the detection point, indicating that there is an obvious stress concentration area near the detection point (in the dotted box in the figure). After calculation, the magnetic field gradient dH / dx value in the stress concentration area reaches 80 (A / m) / mm, which far exceeds the critical stress concentration threshold of 10 (A / m / mm). Therefore, the health status of the tank is poor, which is consistent with the results obtained by the health status determination method provided in the embodiment of the present application.

[0149] In summary, the method for determining the health status of a tank siding provided by the embodiments of this application not only effectively determines whether a tank is currently healthy, but also accurately determines the tank's current risk level. Compared to related art methods that only provide safety thresholds, this method can further evaluate tanks in a safe state, thereby helping personnel reasonably predict the tank's operating load capacity, thereby ensuring safe tank operation. It also reduces maintenance workload and improves maintenance efficiency.

[0150] Moreover, since a correction coefficient is established in the method provided in the embodiments of the present application, the method can be applied to storage tanks of different heights, different inner diameters, and different wall thicknesses. The process is simple to operate, and the current health status of the storage tank can be obtained by simply measuring the wall corrosion depth, which greatly shortens the detection cycle and improves detection efficiency.

[0151] like Figure 5 As shown, the embodiment of the present application further provides a device 100 for determining the health status of a tank wall panel, the device comprising:

[0152] An acquisition module 101 is used to acquire tank information and wall plate corrosion information. The tank information includes material mechanical parameters, size parameters, and medium parameters in the tank. The wall plate corrosion information includes the location and corrosion depth of each corrosion point.

[0153] The acquisition module 101 is further used to obtain a preset maximum stress calculation model for the storage tank. The maximum stress calculation model for the storage tank is obtained by assigning solution conditions to the finite element model of the storage tank and then performing a fitting process. The solution conditions include load conditions and boundary conditions.

[0154] A calculation module 102 is configured to calculate a health status index of the storage tank based on the safety factor of the storage tank, a maximum stress calculation model of the storage tank, storage tank information, and wall plate corrosion information;

[0155] The determination module 103 is used to determine the risk level of the storage tank according to a preset correspondence between the health status index and the risk level. The risk level is used to determine the health status of the storage tank.

[0156] The tank wall plate health determination device 100 provided in the embodiment of the present application obtains tank information and tank wall plate corrosion information through the acquisition module 101. These information can reflect the current corrosion status of the tank. Then, the calculation module 102 can calculate the health status index of the tank based on the two acquired information, as well as the preset tank maximum stress calculation model and the tank safety factor. Next, by substituting the tank health status index into the preset correspondence between the status index and the risk level, the risk level corresponding to the health status index can be obtained, and then the determination module 103 can determine the current health status of the tank according to the risk level. Therefore, the tank wall plate health determination device 100 provided in the embodiment of the present application takes into account the current corrosion status of the tank, the maximum stress status of the tank, and the corresponding safety factor. These parameters have a high reference value for judging the health status of the tank. Therefore, the tank risk level obtained on this basis is relatively accurate, can effectively reflect the current health status of the tank, and help staff reasonably predict the operating carrying capacity of the tank, thereby ensuring the safety of the tank operation.

[0157] In some implementations of the present application, the acquisition module 101 is further configured to acquire the maximum allowable corrosion depth t of the tank wall. max , 0 <t max ≤3.5mm.

[0158] In some implementations of the embodiments of the present application, the calculation module 102 is further configured to:

[0159] Using the dichotomy method in 0~t max Set N groups of different corrosion depths, N ≥ 8;

[0160] Construct a geometric model of the tank based on the tank information and wall corrosion information;

[0161] The finite element method is used to discretize the geometric model and impose solution conditions to obtain the maximum stress of the tank corresponding to N groups of different corrosion depths.

[0162] The relationship between corrosion depth and maximum stress of the tank is fitted to obtain the maximum stress calculation model of the tank.

[0163] The calculation module 102 calculates the maximum allowable corrosion depth t max, the calculation is performed according to the following relationship:

[0164] t max =0.35T

[0165] Where, T is the thickness of the tank wall;

[0166] If the t calculated by this relationship max When it is greater than 3.5mm, t max =3.5mm.

[0167] In some implementations of the embodiments of the present application, the computing module 102 is further configured to:

[0168] Based on N groups of different corrosion depths and their corresponding maximum stresses of the tank, a stress-corrosion function is obtained by fitting;

[0169] A correction coefficient is established to correct the stress-corrosion function and obtain the maximum stress calculation model of the storage tank.

[0170] Among them, the expression of the maximum stress calculation model of the storage tank is:

[0171]

[0172] Where σ is the maximum stress value of the tank, Pa; C is the correction coefficient; H is the height of the tank, m; D is the inner diameter of the tank, D0 = 30m; T is the wall thickness, m; t is the corrosion depth, m; ρ is the medium density, kg / m 3 ; g is the acceleration due to gravity, N / kg;

[0173] The correction factor is obtained through the following relationship:

[0174] C=C H ·C D ·C t

[0175] C H =1.15

[0176] C D =17.25 / D0

[0177] C t =T / (11.76-0.02|t|)

[0178] Among them, C H is the altitude correction factor; C D is the inner diameter correction parameter, 1 / m; D0 is the reference inner diameter, m; C t is the corrosion correction parameter, m.

[0179] In some implementations of the embodiments of the present application, the computing module 102 is further configured to:

[0180] The health index of the tank is calculated according to the following relationship:

[0181]

[0182] Where Q is the health index; σ is the maximum stress value of the tank, Pa; R eL is the yield strength, Pa; K is the safety factor, take K = 1.2.

[0183] In some implementations of the embodiments of the present application, the determining module 103 is further configured to:

[0184] When the health status index is less than 0.6283, the risk level of the tank is determined to be excellent;

[0185] When the health status index is not less than 0.6283 and not greater than 0.85146, the risk level of the storage tank is determined to be medium;

[0186] When the health status index is greater than 0.85146, the risk level of the tank is determined to be poor.

[0187] In some implementations of the embodiments of the present application, the determining module 103 is further configured to:

[0188] Determine tank treatment measures based on risk level, including:

[0189] When the risk level of the storage tank is poor, the treatment measure is determined to be immediate maintenance of the storage tank;

[0190] When the risk level of the storage tank is medium, the treatment measure is determined to be focusing on monitoring the storage tank;

[0191] When the risk level of the storage tank is excellent, the treatment measure is determined to be normal use of the storage tank.

[0192] In summary, the tank siding health status determination device provided by the embodiments of the present application can not only effectively determine whether a tank is currently healthy, but also accurately determine the tank's current risk level. Compared with the related art method that only provides a safety threshold, this device can further evaluate a tank in a safe state, thereby helping personnel to reasonably predict the tank's operating load capacity, thereby ensuring the tank's safe operation. It also reduces maintenance workload and improves maintenance efficiency.

[0193] Moreover, since the calculation module provided in the embodiment of the present application establishes a correction coefficient when establishing the maximum stress calculation model of the storage tank, the present device can be applied to storage tanks of different heights, different inner diameters, and different wall thicknesses. The process operation is simple, and the current health status of the storage tank can be obtained by only measuring the wall corrosion depth, which greatly shortens the detection cycle and improves the detection efficiency.

[0194] In this application, it should be understood that the terms "first", "second", "third", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0195] The above description is only for the purpose of facilitating those skilled in the art to understand the technical solution of this application and is not intended to limit this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.

Claims

1. A method for determining the health status of a tank wall panel, characterized in that: The method comprises: Acquire storage tank information and wall plate corrosion information, wherein the storage tank information includes material mechanical parameters, size parameters, and medium parameters in the storage tank, and the wall plate corrosion information includes the location and corrosion depth of each corrosion point; Obtaining a preset maximum stress calculation model for the storage tank, wherein the maximum stress calculation model for the storage tank is obtained by assigning solution conditions to a finite element model of the storage tank and then performing a fitting process, wherein the solution conditions include load conditions and boundary conditions; Calculating a health status index of the storage tank according to the safety factor of the storage tank, the storage tank information, the wall plate corrosion information, and the storage tank maximum stress calculation model; Determining the risk level of the storage tank according to a preset correspondence between the health status index and the risk level, wherein the risk level is used to determine the current health status of the storage tank; The maximum stress calculation model of the storage tank is obtained by the following method: Get the maximum allowable corrosion depth t of the tank wall max , 0 <t max ≤3.5mm; Using the dichotomy method in 0~t max Set N groups of different corrosion depths, N ≥ 8; Constructing a geometric model of the storage tank based on the storage tank information and the wall plate corrosion information; The geometric model is discretized using a finite element method, and the solution condition is applied to obtain the maximum stress of the storage tank corresponding to the N groups of different corrosion depths; Fitting the relationship between the corrosion depth and the maximum stress of the storage tank to obtain a calculation model for the maximum stress of the storage tank; The step of calculating the health status index of the storage tank according to the safety factor of the storage tank, the tank information, the wall plate corrosion information, and the maximum stress calculation model of the storage tank includes: The health status index of the storage tank is calculated according to the following relationship: Where Q is the health index; σ is the maximum stress value of the tank, Pa; R eL is the yield strength, Pa; K is the safety factor, take K = 1.

2.

2. The method for determining the health status of a tank wall panel according to claim 1, characterized in that: The maximum allowable corrosion depth t of the tank wall is obtained max ,include: The maximum allowable corrosion depth t is obtained according to the following relationship max : t max =0.35T Where, T is the thickness of the tank wall; When t calculated by the above relationship max When it is greater than 3.5 mm, let t max =3.5mm.

3. The method for determining the health status of a tank wall panel according to claim 1, wherein: The fitting process of the relationship between the corrosion depth and the maximum stress of the storage tank to obtain the maximum stress calculation model of the storage tank includes: A stress-corrosion function is obtained by fitting the N groups of different corrosion depths and their corresponding maximum stresses of the storage tank; Establishing a correction coefficient to correct the stress-corrosion function and obtain the maximum stress calculation model of the storage tank, The expression of the maximum stress calculation model of the storage tank is: Wherein, σ is the maximum stress value of the tank, Pa; C is the correction coefficient; H is the height of the tank, m; D is the inner diameter of the tank, m; T is the wall thickness, m; t is the corrosion depth, m; ρ is the medium density, kg / m 3 ; g is the acceleration due to gravity, N / kg; The correction coefficient is obtained by the following relationship: C=C H ·C D ·C t C H ＝1.15×10 3 C D =17.25 / D0 C t =T / (11.76-0.02|t|) Among them, C H is the altitude correction factor; C D is the inner diameter correction parameter, 1 / m; D0 is the reference inner diameter, take D0 = 30m; C t is the corrosion correction parameter, m.

4. The method for determining the health status of a tank wall panel according to claim 1, wherein: The step of determining the risk level of the storage tank according to the preset correspondence between the health status index and the risk level includes: When the health status index is less than 0.6283, the risk level of the storage tank is determined to be excellent; When the health status index is not less than 0.6283 and not greater than 0.85146, the risk level of the storage tank is determined to be medium; When the health status index is greater than 0.85146, the risk level of the storage tank is determined to be poor.

5. The method for determining the health status of a tank wall panel according to claim 1 or 4, characterized in that: After determining the risk level of the storage tank, the method further includes: Tank handling measures are determined based on the risk level, and the tank handling measures include immediate maintenance, intensive monitoring, and normal use.

6. The method for determining the health status of a tank wall panel according to claim 5, characterized in that: The determining of storage tank treatment measures based on the risk level includes: When the risk level of the storage tank is poor, immediately maintain the storage tank; When the risk level of the storage tank is medium, the storage tank is monitored intensively; When the risk level of the storage tank is excellent, the storage tank is used normally.

7. A device for determining the health status of a tank wall panel, characterized in that: The device comprises: An acquisition module is used to acquire storage tank information and wall plate corrosion information, wherein the storage tank information includes material mechanical parameters, size parameters and medium parameters in the storage tank, and the wall plate corrosion information includes the location and corrosion depth of each corrosion point; The acquisition module is further configured to acquire a preset maximum stress calculation model for the storage tank, wherein the maximum stress calculation model for the storage tank is obtained by assigning solution conditions to a finite element model of the storage tank and then performing a fitting process, wherein the solution conditions include load conditions and boundary conditions; a calculation module, configured to calculate a health status index of the storage tank based on the safety factor of the storage tank, the maximum stress calculation model of the storage tank, the storage tank information, and the wall plate corrosion information; a determination module, configured to determine the risk level of the storage tank according to a preset correspondence between a health status index and a risk level, wherein the risk level is used to determine the health status of the storage tank; Wherein, the acquisition module is further used for: Get the maximum allowable corrosion depth t of the tank wall max , 0 <t max ≤3.5mm; The calculation module is also used for: Using the dichotomy method in 0~t max Set N groups of different corrosion depths, N ≥ 8; Constructing a geometric model of the storage tank based on the storage tank information and the wall plate corrosion information; The geometric model is discretized using a finite element method, and the solution condition is applied to obtain the maximum stress of the storage tank corresponding to the N groups of different corrosion depths; Fitting the relationship between the corrosion depth and the maximum stress of the storage tank to obtain a calculation model for the maximum stress of the storage tank; The calculation module is further configured to: The health status index of the storage tank is calculated according to the following relationship: Where Q is the health index; σ is the maximum stress value of the tank, Pa; R eL is the yield strength, Pa; K is the safety factor, take K = 1.

2.

8. The device for determining the health status of a tank wall panel according to claim 7, wherein: The determining module is further configured to: Tank handling measures are determined based on the risk level, and the tank handling measures include immediate maintenance, intensive monitoring, and normal use.

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