Method and system for evaluating the influence of stray current corrosion on metal pipelines

Abstract

The application discloses a metal pipeline stray current corrosion influence evaluation method and system, and relates to the technical field of pipeline safety evaluation, and aims at specific evaluation objects, comprehensively considers relevant factors that may have influence on evaluation results, establishes a metal pipeline stray current influence simulation calculation model under specific environment and obtains stray current distribution calculation values; meanwhile, based on soil environment of the evaluation objects, a metal stray current electrochemical corrosion test model is established and metal polarization potential offset test values are obtained; then, through a combination of simulation and test, a stray current and polarization potential offset coupling relationship under specific environment is established, and metal pipeline corrosion comprehensive evaluation indexes are determined, so as to realize accurate evaluation of stray current corrosion influence safety. The application realizes accurate evaluation of metal pipeline stray current corrosion safety from multiple aspects, and has important significance for effectiveness of stray current protection means and scientificity of monitoring methods.

Description

Technical Field

[0001] This invention belongs to the technical field of stray current protection for urban rail transit and corrosion protection for buried metal pipelines, specifically relating to a method and system for evaluating the impact of stray current corrosion on metal pipelines. Background Technology

[0002] Currently, due to urban space constraints, it is difficult for subway tunnels to have a large distance from underground facilities. Subway tunnels, station buildings, etc. are usually located in densely built-up urban areas. Subway planning faces the problem of tunnels being adjacent to or parallel to metal gas pipes, water pipes, heating pipes, sewage pipes, and power and communication pipes.

[0003] In practical engineering, stray currents are distributed in the environmental medium in the form of a current field, making them difficult to measure directly. In engineering practice, the polarization potential shift of metals affected by stray currents is usually used as an indicator of its impact. Current assessment work mainly focuses on monitoring the polarization potential at the cathodic protection terminals along the pipeline. However, there are significant differences in the limits for metal polarization potential shifts among various industry standards. Furthermore, since there is no necessary correlation between metal polarization potential shift, stray current leakage, and metal corrosion, and the relationship between these three factors varies under different environments, existing fixed assessment methods cannot accurately reflect the true impact of stray current corrosion on metal pipelines. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art. This invention provides a method and system for evaluating the impact of stray current corrosion on metal pipelines. This invention comprehensively achieves accurate assessment of the safety of stray current corrosion of metal pipelines from multiple aspects, which is of great significance for the effectiveness of stray current protection measures and the scientific nature of monitoring methods.

[0005] To achieve the desired effect, the present invention adopts the following technical solution:

[0006] This invention provides a method for evaluating the impact of stray current corrosion on metal pipelines, comprising:

[0007] A simulation model of the impact of stray current in metal pipelines was constructed, and the stray current density was simulated and calculated to obtain the simulation numerical results.

[0008] A soil environmental test model was constructed and a metal stray current electrochemical corrosion test was conducted to obtain simulation test results;

[0009] The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained based on the simulation numerical calculation results and the simulation test results.

[0010] The safety evaluation results are obtained by comparing the experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion with the corresponding preset values.

[0011] Furthermore, the experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion include at least one of the following: the influence range of the positive stray current of the metal pipeline, the total amount of the positive stray current within a preset time period, the peak hour metal polarization potential shift value, and the annual metal corrosion amount.

[0012] Furthermore, the step of comparing the experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion with the corresponding preset values ​​to obtain the safety evaluation result specifically includes:

[0013] The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion are compared with the corresponding preset values ​​in the following order: the influence range of the positive stray current of the metal pipeline, the total amount of the positive stray current within the preset time period, the peak hour metal polarization potential shift value, and the annual metal corrosion amount.

[0014] If the experimental value of any comprehensive corrosion assessment index for a metal pipeline exceeds the corresponding preset value, the safety assessment is deemed unqualified; otherwise, the safety assessment is deemed qualified.

[0015] Furthermore, when the safety assessment is deemed unqualified, relevant measures are taken to adjust the experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion until the safety assessment is deemed qualified.

[0016] Furthermore, the formula for calculating the total amount of forward stray current within the preset time period is as follows:

[0017]

[0018] In the formula, I represents the total positive stray current within a preset time period. c (t) represents the total stray current in the metal pipeline at time t, and T is the preset time period.

[0019] Furthermore, the formula for calculating the peak hour metal polarization potential offset is as follows:

[0020] U=k*L p (t),

[0021] In the formula, U is the peak hour metal polarization potential offset value, and I p (t) represents the average stray current during peak hours at the calculated location, and k is the ratio coefficient between the stray current density and the metal polarization potential shift in a specific environment.

[0022] Furthermore, the formula for calculating the annual corrosion amount of the metal is as follows:

[0023]

[0024] In the formula, P is the annual corrosion amount of the metal, I(t) is the total stray current at time t, K is the electrochemical equivalent of the metal, and T is the preset time period.

[0025] Furthermore, the experimental values ​​for obtaining the comprehensive evaluation index of metal pipeline corrosion based on simulation numerical calculation results and simulation test results specifically include:

[0026] The stray current density distribution data of the entire metal pipeline is extracted from the simulation numerical calculation results, and the stray current density and metal polarization potential shift ratio data are extracted from the simulation test results.

[0027] Based on the stray current density distribution data of the entire metal pipeline and the stray current density and metal polarization potential shift ratio data, experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained.

[0028] Furthermore, the specific steps of obtaining the experimental values ​​for the comprehensive corrosion assessment index of the metal pipeline based on the stray current density distribution data of the entire metal pipeline and the stray current density to metal polarization potential shift ratio data include:

[0029] The data on the stray current density distribution along the entire metal pipeline are used to obtain at least one of the following: the influence range of the positive stray current in the metal pipeline, the total amount of the positive stray current within a preset time period, and the annual metal corrosion.

[0030] The peak hour metal polarization potential offset value was obtained by using stray current density distribution data and metal polarization potential offset ratio data for the entire metal pipeline.

[0031] This invention discloses a system for evaluating the impact of stray current corrosion on metal pipelines, comprising:

[0032] The data acquisition module is used to collect various parameters for evaluating the impact of stray current corrosion on metal pipelines.

[0033] The evaluation module is used to evaluate the impact of stray current corrosion on metal pipelines according to any of the aforementioned methods.

[0034] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention provides a method and system for evaluating the impact of stray current corrosion on metal pipelines. Targeting a specific evaluation object, this invention comprehensively considers relevant factors that may affect the evaluation results, including but not limited to the soil structure of the environment where the evaluation object is located, the planning of nearby urban rail transit networks and other nearby buried metal pipeline networks, and the energy transmission process of the urban rail transit traction power supply system. It establishes a simulation calculation model of the impact of stray current on metal pipelines under specific conditions and obtains calculated values ​​of stray current distribution. Simultaneously, based on the soil environment of the evaluation object, it establishes an electrochemical corrosion test model of metal stray current and obtains test values ​​of metal polarization potential shift. Then, through a combination of simulation and experiment, it establishes the coupling relationship between stray current and polarization potential shift under specific conditions, determines the comprehensive evaluation index of metal pipeline corrosion, and achieves an accurate evaluation of the safety impact of stray current corrosion. This invention comprehensively achieves an accurate assessment of the safety of metal pipeline stray current corrosion from multiple aspects, which is of great significance for the effectiveness of stray current protection measures and the scientific nature of monitoring methods. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a flowchart of a method for evaluating the impact of stray current corrosion on metal pipelines, provided in an embodiment of the present invention.

[0037] Figure 2 This is a schematic diagram of a soil environment simulated metal stray current electrochemical corrosion test provided by an embodiment of the present invention.

[0038] Figure 3 This is a schematic diagram of a simulation model of the influence of stray current in metal pipelines provided in an embodiment of the present invention.

[0039] Figure 4 This is a schematic diagram of a soil environmental test model provided in an embodiment of the present invention.

[0040] Figure 5 This is a driving plan representation provided by an embodiment of the present invention.

[0041] Figure 6 This is a schematic diagram of stray current distribution in a metal pipeline provided by an embodiment of the present invention.

[0042] Figure 7This is a schematic diagram of a metal polarization potential shift test model under a specific environment provided by an embodiment of the present invention.

[0043] Figure 8 This is a schematic diagram of stray current density and metal polarization potential offset ratio data provided in an embodiment of the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Establishing a stray current impact model for buried metal pipelines under specific environments requires considering the soil structure of the environment in which the evaluation object is located, the planning of nearby urban rail transit networks and other nearby buried metal pipeline networks, as well as the energy transmission process of the urban rail transit traction power supply system. For the evaluation object, establishing a calculation model that closely matches actual working conditions is fundamental to ensuring an accurate assessment of the safety of stray current corrosion of metal pipelines.

[0046] Establishing a coupling relationship between stray current and polarization potential for specific environments is crucial. In practical engineering, stray currents are distributed in the environmental medium as a current field, making direct measurement difficult. In engineering, the polarization potential shift caused by stray currents on metals is often used as an evaluation index of the degree of stray current influence. However, due to limitations imposed by reference electrodes and environmental factors, polarization potential can only be obtained through testing, not simulation calculations. The corrosion of metal pipelines of different materials in different soil environments should not be evaluated using fixed polarization potential shift values. Therefore, establishing a coupling relationship between stray current and polarization potential for specific environments is a key technical support for accurately assessing the safety of stray current corrosion of metal pipelines, and is of great significance for the safety assessment of metal pipeline corrosion.

[0047] See Figures 1 to 8 The present invention provides a method for evaluating the impact of stray current corrosion on metal pipelines, comprising:

[0048] A simulation model of the stray current impact of metal pipelines was constructed, and the stray current density was simulated and calculated to obtain the simulation numerical results. Specifically, based on the soil structure of the environment where the evaluation object is located, the planning of the urban rail transit network in the vicinity, and the planning of the buried metal pipeline network in the vicinity, a simulation model of the stray current impact of metal pipelines under specific conditions was established. The stray current density of the entire line was simulated and calculated for the simulation model of the stray current impact of metal pipelines under specific conditions, and the simulation numerical results were obtained.

[0049] A soil environment test model was constructed and a stray current electrochemical corrosion test of metal was conducted to obtain simulation test results. Specifically, based on the soil environment in which the evaluation object is located, a metal polarization potential shift test model under a specific environment was established, and a stray current electrochemical corrosion test of metal was carried out based on the metal polarization potential shift test model under a specific environment to obtain simulation test results.

[0050] The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained based on the simulation numerical calculation results and the simulation test results.

[0051] Specifically, stray current density distribution data of the entire metal pipeline is extracted from the simulation numerical calculation results, and stray current density and metal polarization potential shift ratio data are extracted from the simulation test results.

[0052] Based on the stray current density distribution data of the entire metal pipeline and the stray current density and metal polarization potential shift ratio data, experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained.

[0053] Furthermore, the specific steps of obtaining the experimental values ​​for the comprehensive corrosion assessment index of the metal pipeline based on the stray current density distribution data of the entire metal pipeline and the stray current density to metal polarization potential shift ratio data include:

[0054] The data on the stray current density distribution along the entire metal pipeline are used to obtain at least one of the following: the influence range of the positive stray current in the metal pipeline, the total amount of the positive stray current within a preset time period, and the annual metal corrosion.

[0055] The peak hour metal polarization potential offset value is obtained by using stray current density distribution data and metal polarization potential offset ratio data for the entire metal pipeline.

[0056] The safety evaluation results are obtained by comparing the experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion with the corresponding preset values.

[0057] This invention targets a specific evaluation object and comprehensively considers relevant factors that may affect the evaluation results, including but not limited to the soil structure of the evaluation object's environment, the planning of nearby urban rail transit networks and other nearby buried metal pipeline networks, and the energy transmission process of the urban rail transit traction power supply system. It establishes a simulation calculation model for the impact of stray current on metal pipelines under specific conditions and obtains calculated values ​​of stray current distribution. Simultaneously, based on the soil environment of the evaluation object, it establishes an electrochemical corrosion test model for metal stray current and obtains measured values ​​of metal polarization potential shift. Then, through a combination of simulation and experimentation, it establishes the coupling relationship between stray current and polarization potential shift under specific conditions, determines comprehensive evaluation indicators for metal pipeline corrosion, and achieves an accurate evaluation of the safety impact of stray current corrosion. This invention comprehensively achieves an accurate assessment of the safety of metal pipeline stray current corrosion from multiple aspects, which is of great significance for the effectiveness of stray current protection measures and the scientific nature of monitoring methods.

[0058] Preferably, the experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion include at least one of the following: the influence range L of the positive stray current of the metal pipeline, the total amount I of the positive stray current within a preset time period (e.g., 24 hours), the peak hour metal polarization potential offset value U, and the annual metal corrosion amount P.

[0059] On the one hand, the comparison of experimental values ​​of comprehensive corrosion assessment indicators for metal pipelines with corresponding preset values ​​to obtain safety evaluation results specifically includes:

[0060] The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion are compared with the corresponding preset values ​​in the following order: the influence range of the positive stray current of the metal pipeline, the total amount of the positive stray current within the preset time period, the peak hour metal polarization potential shift value, and the annual metal corrosion amount.

[0061] If the experimental value of any comprehensive corrosion assessment index for a metal pipeline exceeds the corresponding preset value, the safety assessment is deemed unqualified; otherwise, the safety assessment is deemed qualified.

[0062] On the other hand, when the safety assessment is unqualified, relevant measures are taken to adjust the experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion until the safety assessment is qualified. The stray current corrosion impact assessment method for metal pipelines of this invention has an adaptive optimization function. When the safety assessment is unqualified, it can automatically take relevant measures to adjust the experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion until the safety assessment is qualified. Specifically, corresponding measures can be taken to reduce stray current leakage from rails or to strengthen the protection of metal pipelines to reduce the impact of stray current. After relevant measures are taken in the project, a reassessment is conducted to verify the effectiveness of the measures. For lines under construction, an assessment is generally required in advance, and relevant parameters are optimized based on the assessment results to guide the engineering design. For lines already in operation, the impact caused during current operation can be assessed. If the assessment result is unqualified, relevant measures need to be taken for the project to make the safety assessment result qualified.

[0063] Preferably, the relevant measures include at least one of the following: increasing the rail-to-ground transition resistance, reducing the longitudinal resistance of traction current return, using cathodic protection for metal pipelines, and strengthening the insulating coating of metal pipelines.

[0064] Specifically, for urban rail transit: maintain a clean track environment, increase the rail-to-ground transition resistance, and use parallel cables to reduce the longitudinal resistance of traction current return. For pipeline protection: adopt cathodic protection; for severely affected sections, strengthen the insulation coating, etc.

[0065] In a preferred embodiment, the preset value of the influence range of the positive stray current of the metal pipeline is the maximum stray current influence range; correspondingly, the safety evaluation condition for the influence range of the positive stray current of the metal pipeline is that the experimental value of the influence range of the positive stray current of the metal pipeline is not greater than the maximum stray current influence range.

[0066] In one embodiment, the formula for calculating the total amount of forward stray current within the preset time period is:

[0067]

[0068] In the formula, I represents the total positive stray current within a preset time period. c (t) represents the total stray current in the metal pipeline at time t, and T is the preset time period.

[0069] Specifically, the preset value of the total positive stray current within the preset time period is the total positive stray current within the maximum preset time period (e.g., within 24 hours). The safety evaluation condition corresponding to the total positive stray current within the preset time period is that the experimental value of the total positive stray current within the preset time period is not greater than the total positive stray current within the maximum preset time period.

[0070] In another embodiment, the formula for calculating the peak hour metal polarization potential offset is:

[0071] U = k * I p (t),

[0072] In the formula, U is the peak hour metal polarization potential offset value, and I p (t) represents the average stray current during peak hours at the calculated location, and k is the ratio coefficient between the stray current density in a specific environment and the metal polarization potential shift.

[0073] Specifically, the preset value of the peak hour metal polarization potential offset value is the maximum peak hour metal polarization potential offset value, and the safety evaluation condition corresponding to the peak hour metal polarization potential offset value is that the experimental value of the peak hour metal polarization potential offset value is not greater than the maximum peak hour metal polarization potential offset value.

[0074] In yet another embodiment, the formula for calculating the annual corrosion amount of the metal is:

[0075]

[0076] In the formula, P is the annual corrosion amount of the metal, I(t) is the total stray current at time t, K is the electrochemical equivalent of the metal, and T is the preset time period.

[0077] Specifically, the preset value of the annual metal corrosion amount is the maximum annual metal corrosion amount, and the safety evaluation condition corresponding to the annual metal corrosion amount is that the experimental value of the annual metal corrosion amount is not greater than the maximum annual metal corrosion amount.

[0078] Preferably, a planning model for the urban rail transit network and the buried metal pipeline network of the adjacent city is established in CDEGS software (e.g., Figure 3 As shown), set the soil structure in the software (e.g. Figure 4 As shown), the train's travel schedule (including time, location, traction current, etc.) between different traction substations is used as the model input (e.g., Figure 5 As shown), the stray current distribution of the metal pipeline throughout the day was calculated (e.g. Figure 6 As shown), through data processing, the influence range L of the positive stray current, the total positive stray current I over 24 hours, and the annual metal corrosion P were obtained. Simultaneously, a metal polarization potential shift test model under specific environmental conditions was established (e.g., Figure 7 As shown, corresponding Figure 2 ), to obtain data on the stray current density and the proportionality coefficient of the metal polarization potential shift (e.g. Figure 8As shown in the diagram (i.e., the "coupling relationship"), the distribution of stray currents in the metal pipeline throughout the day is calculated. Through data processing, the peak hourly metal polarization potential shift value U is obtained, thereby enabling the assessment. Specifically, the coupling relationship refers to the polarization potential shift (mV) caused by a unit stray current (e.g., 1 mA) flowing out from a unit area, based on the specific metal material of the evaluation object and its actual soil environment. This can ultimately be expressed as **mV / mA ​​(polarization potential shift caused by a unit stray current).

[0079] CDEGS (Current Distribution, Electromagnetic Fields, Grounding and Soil Structure Analysis) is a power system design and analysis software that can quickly and accurately simulate complex electromagnetic field distributions, grounding system structures and soil characteristics in power systems, as well as communication interference issues in high-voltage transmission lines and substations.

[0080] This invention proposes a stray current corrosion evaluation method for buried metal pipelines, addressing various specific environments. It comprehensively assesses the safety of stray current corrosion from multiple perspectives, significantly enhancing the effectiveness of stray current protection measures and the scientific rigor of monitoring methods. This invention provides important guidance for urban rail transit network planning, stray current corrosion impact assessment of metal pipelines, and potential pipeline relocation. Specifically, this invention establishes targeted evaluation simulation and experimental models for particular evaluation objects, selecting multiple indicators to comprehensively evaluate the corrosion impact of stray currents, demonstrating high engineering feasibility and scalability.

[0081] Based on the same inventive concept, this invention discloses a system for evaluating the impact of stray current corrosion on metal pipelines, comprising:

[0082] The data acquisition module is used to collect various parameters for evaluating the impact of stray current corrosion on metal pipelines.

[0083] The evaluation module is used to evaluate the impact of stray current corrosion on metal pipelines according to any of the aforementioned methods.

[0084] The system embodiments described herein can be implemented one-to-one with the aforementioned method embodiments, and will not be repeated here.

[0085] This invention can accurately assess the impact of stray current corrosion on specific objects, reduce potential economic losses in the urban rail transit industry and the underground metal pipeline corrosion protection industry, and has high prospects for promotion and economic and social benefits.

[0086] Based on the same inventive concept, this invention also discloses an electronic device, which may include: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus. The processor can call logical instructions from the memory to execute a method for evaluating the impact of stray current corrosion on metal pipelines, including:

[0087] A simulation model of the impact of stray current in metal pipelines was constructed, and the stray current density was simulated and calculated to obtain the simulation numerical results.

[0088] A soil environmental test model was constructed and a metal stray current electrochemical corrosion test was conducted to obtain simulation test results;

[0089] The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained based on the simulation numerical calculation results and the simulation test results.

[0090] The safety evaluation results are obtained by comparing the experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion with the corresponding preset values.

[0091] Furthermore, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0092] On the other hand, embodiments of the present invention also provide a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, and when the program instructions are executed by a computer, the computer is able to execute a method for evaluating the impact of stray current corrosion on metal pipelines provided in the above-described method embodiments, including:

[0093] A simulation model of the impact of stray current in metal pipelines was constructed, and the stray current density was simulated and calculated to obtain the simulation numerical results.

[0094] A soil environmental test model was constructed and a metal stray current electrochemical corrosion test was conducted to obtain simulation test results;

[0095] The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained based on the simulation numerical calculation results and the simulation test results.

[0096] The safety evaluation results are obtained by comparing the experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion with the corresponding preset values.

[0097] In another aspect, embodiments of the present invention also provide a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements a method for evaluating the impact of stray current corrosion on metal pipelines provided in the above embodiments, including:

[0098] A simulation model of the impact of stray current in metal pipelines was constructed, and the stray current density was simulated and calculated to obtain the simulation numerical results.

[0099] A soil environmental test model was constructed and a metal stray current electrochemical corrosion test was conducted to obtain simulation test results;

[0100] The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained based on the simulation numerical calculation results and the simulation test results.

[0101] The safety evaluation results are obtained by comparing the experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion with the corresponding preset values.

[0102] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for evaluating the impact of stray current corrosion on metal pipelines, characterized in that, include: A simulation model of the impact of stray current in metal pipelines was constructed, and the stray current density was simulated and calculated to obtain the simulation numerical results. A soil environmental test model was constructed and a metal stray current electrochemical corrosion test was conducted to obtain simulation test results; The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained based on the simulation numerical calculation results and the simulation test results. The experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion include at least one of the following: the influence range of positive stray current in the metal pipeline, the total amount of positive stray current within a preset time period, the peak hour metal polarization potential shift value, and the annual metal corrosion amount. The formula for calculating the total amount of positive stray current within the preset time period is: ； In the formula, I represents the total positive stray current within a preset time period. The total stray current in the metal pipeline at time t is T, where T is the preset time period. The formula for calculating the peak hour metal polarization potential offset is as follows: ， In the formula, U is the peak hour metal polarization potential offset value. To calculate the average stray current during peak hours at a given location, k is the ratio of stray current density in a specific environment to the metal polarization potential shift. The formula for calculating the annual corrosion amount of the metal is: ； In the formula, P represents the annual corrosion rate of the metal. Let t be the total stray current in the metal pipeline, K be the metal electrochemical equivalent, and T be the preset time period; The experimental values ​​for obtaining the comprehensive evaluation index of metal pipeline corrosion based on simulation numerical calculation results and simulation test results specifically include: The stray current density distribution data of the entire metal pipeline is extracted from the simulation numerical calculation results, and the stray current density and metal polarization potential shift ratio data are extracted from the simulation test results. Based on the stray current density distribution data of the entire metal pipeline and the stray current density and metal polarization potential shift ratio data, experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion were obtained. The safety evaluation results are obtained by comparing the experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion with the corresponding preset values.

2. The method for evaluating the impact of stray current corrosion on metal pipelines as described in claim 1, characterized in that, The process of comparing the experimental values ​​of the comprehensive evaluation index for metal pipeline corrosion with the corresponding preset values ​​to obtain the safety evaluation results specifically includes: The experimental values ​​of the comprehensive evaluation index of metal pipeline corrosion are compared with the corresponding preset values ​​in the following order: the influence range of the positive stray current of the metal pipeline, the total amount of the positive stray current within the preset time period, the peak hour metal polarization potential shift value, and the annual metal corrosion amount. If the experimental value of any comprehensive corrosion assessment index for a metal pipeline exceeds the corresponding preset value, the safety assessment is deemed unqualified; otherwise, the safety assessment is deemed qualified.

3. The method for evaluating the impact of stray current corrosion on metal pipelines as described in claim 2, characterized in that, When the safety assessment is deemed unqualified, relevant measures shall be taken to adjust the experimental values ​​of the comprehensive evaluation index for corrosion of metal pipelines until the safety assessment is deemed qualified.

4. The method for evaluating the impact of stray current corrosion on metal pipelines as described in claim 1, characterized in that, The experimental values ​​for obtaining the comprehensive evaluation index of metal pipeline corrosion based on the stray current density distribution data of the entire metal pipeline and the stray current density to metal polarization potential shift ratio data specifically include: The data on the stray current density distribution along the entire metal pipeline are used to obtain at least one of the following: the influence range of the positive stray current in the metal pipeline, the total amount of the positive stray current within a preset time period, and the annual metal corrosion. The peak hour metal polarization potential offset value is obtained by using stray current density distribution data and metal polarization potential offset ratio data for the entire metal pipeline.

5. A system for evaluating the impact of stray current corrosion on metal pipelines, characterized in that, include: The data acquisition module is used to collect various parameters for evaluating the impact of stray current corrosion on metal pipelines. The evaluation module is used to evaluate the impact of stray current corrosion on metal pipelines according to any one of the methods for evaluating the impact of stray current corrosion on metal pipelines as described in claims 1-4.

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