A pipeline corrosion evaluation method, device, storage medium and system

Abstract

The application discloses a pipeline corrosion evaluation method, device, storage medium and system, a pipeline corrosion evaluation mathematical model under dynamic direct current stray current interference is obtained through statistical fitting regression, a mathematical physics evaluation model of pipeline corrosion is obtained through physical model correction and data fitting, and corrosion evaluation is performed through the mathematical physics evaluation model when pipeline corrosion evaluation is needed, the pipeline corrosion evaluation method, device, storage medium and system improve pipeline corrosion evaluation accuracy and provide data support for pipeline safety management.

Description

Technical Field

[0001] This invention relates to the field of pipeline corrosion assessment technology under dynamic DC stray current interference, and particularly to a pipeline corrosion assessment method, apparatus, computer-readable storage medium and system. Background Technology

[0002] With the booming development of China's economy, the energy and transportation industries have experienced rapid growth. An increasing number of oil and gas pipelines and urban rail transit systems have been built and put into operation, creating a complex network of urban rail transit and buried pipelines. Rail transit systems, such as subways or light rail, generally use DC traction with a running track for current return. Since the track cannot be completely insulated from the ground, some current inevitably leaks from the running track into the earth, interfering with surrounding buried oil and gas pipelines and other metal components. When buried pipelines are damaged, stray currents flow in from one point of damage and out from the other, accelerating metal corrosion at the outlet. This corrosion phenomenon is called dynamic DC stray current corrosion. Establishing a dynamic DC interference assessment method for rail transit is of great significance for ensuring the safe operation of oil and gas pipelines under dynamic DC stray current interference and for the coordinated development of pipeline and subway construction.

[0003] In the existing technology, the current Australian standard selects the potential deviation as a reference indicator, taking into account the metal coating condition and the interference time, and uses the proportion of the time when the pipe ground potential is positive to the protection potential to the total test time as an important reference point.

[0004] However, existing technologies still have the following drawbacks: inaccurate pipeline corrosion assessment.

[0005] Therefore, there is a current need for a pipeline corrosion assessment method, apparatus, computer-readable storage medium, and system to overcome the aforementioned deficiencies in the prior art. Summary of the Invention

[0006] This invention provides a pipeline corrosion assessment method, apparatus, computer-readable storage medium, and system, thereby improving the accuracy of pipeline corrosion assessment and providing data support for pipeline safety management.

[0007] An embodiment of the present invention provides a pipeline corrosion assessment method, the assessment method comprising: acquiring historical dynamic DC interference test data of the pipeline to be assessed; obtaining a mathematical evaluation model of the pipeline to be assessed based on the historical dynamic DC interference test data using a preset statistical fitting regression method, and correcting the mathematical evaluation model using a preset Faraday correction formula to obtain a mathematical-physical evaluation model; acquiring the voltage frequency, voltage amplitude, and potential offset of the pipeline to be assessed in real time; and conducting a corrosion assessment of the pipeline to be assessed based on the voltage frequency, voltage amplitude, and potential offset using the mathematical-physical evaluation model.

[0008] As an improvement to the above scheme, a mathematical evaluation model for the pipeline to be evaluated for corrosion is obtained based on the historical data of the dynamic DC interference test using a preset statistical fitting regression method. Specifically, this includes: setting a test voltage according to a preset electrical parameter data set, and conducting a corrosion weight loss test on a metal sample using the test voltage to obtain a test data set; the electrical parameter data set includes voltage frequency, voltage amplitude, and potential offset; calculating the corrosion rate corresponding to the electrical parameter data set based on the test data set and a preset corrosion weight loss calculation formula; and using the least squares method, performing multivariate function fitting on the voltage frequency, voltage amplitude, potential offset, and corrosion rate based on the test data set and the corresponding corrosion rate to obtain the mathematical evaluation model for the pipeline to be evaluated for corrosion.

[0009] As an improvement to the above scheme, the mathematical evaluation model is modified by a preset Faraday correction formula to obtain a mathematical physical evaluation model. Specifically, this includes: calculating the theoretical expression of corrosion rate according to the preset Faraday correction formula; and modifying the mathematical evaluation model according to the theoretical expression of corrosion rate to obtain a mathematical physical evaluation model.

[0010] As an improvement to the above scheme, the mathematical evaluation model is expressed as: Y = 87.53 + 17.59*X1 - 0.1661*X2 + 9.105*X3; where Y represents the corrosion rate, and the unit is g / dm³. 2 .a; X1 represents amplitude, in volts (V); X2 represents frequency, in mHz; X3 represents interference current density, in amperes (A / m). 2 .

[0011] As an improvement to the above scheme, the theoretical expression for the corrosion rate is: In the formula, T represents the fluctuation period in seconds, A represents the amplitude in volts (V), ω represents the angular frequency, y represents the phase, B represents the offset in volts (V), R represents the system resistance in ohms (Ω), F represents the Faraday constant (96485 C / mol), M is the molar mass of steel (55.85 g / mol), t represents the corrosion time in seconds, and m represents the amount of corrosion in grams.

[0012] As an improvement to the above scheme, the mathematical physics evaluation model expression is as follows: In the formula, V is the corrosion rate (g / cm). 2 ·s); F is the Faraday constant (96485C / mol); M is the molar mass of steel (55.85g / mol); K1 is the correction factor for the influence of corrosion products on the corrosion rate; K2 is the current correction factor caused by capacitance; A is the amplitude of the interference potential; B is the offset; C is the critical potential under the action of dynamic stray current; R is the resistance of the soil system.

[0013] Another embodiment of the present invention provides a pipeline corrosion assessment device, which includes a data acquisition unit, a modeling correction unit, and a corrosion evaluation unit. The data acquisition unit acquires historical dynamic DC interference test data of the pipeline to be assessed, and acquires the voltage frequency, voltage amplitude, and potential offset of the pipeline in real time. The modeling correction unit uses a preset statistical fitting regression method to obtain a mathematical evaluation model of the pipeline to be assessed based on the historical dynamic DC interference test data, and corrects the mathematical evaluation model using a preset Faraday correction formula to obtain a mathematical-physical evaluation model. The corrosion evaluation unit uses the mathematical-physical evaluation model to perform corrosion assessment on the pipeline to be assessed based on the voltage frequency, voltage amplitude, and potential offset.

[0014] As an improvement to the above scheme, the modeling correction unit is further configured to: set a test voltage according to a preset electrical parameter data set, and conduct a corrosion weight loss test on a metal specimen using the test voltage to obtain a test data set; the electrical parameter data set includes voltage frequency, voltage amplitude, and potential offset; calculate the corrosion rate corresponding to the electrical parameter data set based on the test data set and a preset corrosion weight loss calculation formula; and perform multivariate function fitting on the voltage frequency, voltage amplitude, potential offset, and corrosion rate using the least squares method based on the test data set and the corresponding corrosion rate to obtain a mathematical evaluation model for the pipeline to be evaluated for corrosion.

[0015] As an improvement to the above scheme, the modeling correction unit is further used to: calculate the theoretical expression of corrosion rate according to the preset Faraday correction formula; and correct the mathematical evaluation model according to the theoretical expression of corrosion rate to obtain a mathematical physical evaluation model.

[0016] Another embodiment of the present invention provides a computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the pipeline corrosion assessment method as described above.

[0017] Another embodiment of the present invention provides a pipeline corrosion assessment system, the assessment system including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor executes the computer program to implement the pipeline corrosion assessment method as described above.

[0018] Compared with existing technologies, this technical solution has the following beneficial effects:

[0019] This invention provides a pipeline corrosion assessment method, device, computer-readable storage medium, and system. A mathematical model for pipeline corrosion assessment under dynamic DC stray current interference is obtained through statistical fitting and regression. A mathematical-physical assessment model for pipeline corrosion is obtained by correcting the physical model and combining it with data fitting. Corrosion assessment is then performed using this mathematical-physical assessment model when necessary. This pipeline corrosion assessment method, device, computer-readable storage medium, and system improve the accuracy of pipeline corrosion assessment and provide data support for pipeline safety management. Attached Figure Description

[0020] Figure 1 This is a schematic flowchart of a pipeline corrosion assessment method provided in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of a pipeline corrosion assessment device provided in an embodiment of the present invention. Detailed Implementation

[0022] 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. Specific Implementation Example 1

[0024] The present invention first describes a method for assessing pipeline corrosion. Figure 1This is a schematic flowchart of a pipeline corrosion assessment method provided in an embodiment of the present invention.

[0025] like Figure 1 As shown, the pipeline corrosion assessment method includes:

[0026] S1: Obtain historical data of dynamic DC interference test of the pipeline to be evaluated for corrosion.

[0027] In order to evaluate the pipeline to be assessed for corrosion, historical data of the pipeline under dynamic DC stray current interference (described in this article as "Dynamic DC Interference Test Historical Data") are first collected, including but not limited to: cathodic protection potential, AC voltage, soil resistivity, voltage frequency, voltage amplitude and current density.

[0028] The dynamic DC stray current interference information of the pipeline under test is obtained by installing an automatic potential acquisition instrument at the test point of the pipeline. This instrument can be used for long-term continuous detection, measurement, and storage of pipeline cathodic protection potential, pipeline AC voltage, etc. Based on the dynamic potential fluctuation curve of the pipeline under test obtained by the automatic potential acquisition instrument, the fluctuation amplitude A (unit: V), fluctuation frequency B (unit: Hz), and potential offset C (unit: V) are obtained. For soil resistivity, a deep resistivity meter is used for measurement. The soil resistivity measurement is performed according to Section 11 of GB / T21246-2007 "Methods for Measurement of Cathodic Protection Parameters of Buried Steel Pipelines". A deep resistivity meter (ZC-8) is used at the test point, employing the Wenner four-level method, to finally obtain the soil resistivity k (unit: Ω·m).

[0029] In addition to historical data from dynamic DC interference testing, corrosion assessment also requires obtaining pipeline information for the pipeline to be evaluated. Specifically, this includes basic pipeline information and pipeline fault and maintenance information. Basic pipeline information includes the pipeline's unit of measurement, operating pressure, wall thickness, material, density, electrical conductivity, anti-corrosion coating condition, and cathodic protection status. Collecting this basic information allows for a preliminary assessment of the pipeline's overall condition, preparing for further quantitative evaluation. Pipeline fault and maintenance information includes detection time, fault cause, maintenance time, fault location, and maintenance measures. This information provides insights into pipeline faults and maintenance status, offering forward-looking information for subsequent quantitative evaluation of pipeline corrosion.

[0030] S2: Using a preset statistical fitting regression method, a mathematical evaluation model for the pipeline to be corroded is obtained based on the historical data of the dynamic DC interference test. The mathematical evaluation model is then corrected using a preset Faraday correction formula to obtain a mathematical-physical evaluation model.

[0031] In one embodiment, a mathematical evaluation model for the pipeline to be evaluated for corrosion is obtained based on the historical data of the dynamic DC interference test using a preset statistical fitting regression method. Specifically, this includes: setting a test voltage according to a preset electrical parameter data set, and conducting a corrosion weight loss test on a metal sample using the test voltage to obtain a test data set; calculating the corrosion rate corresponding to the electrical parameter data set based on the test data set and a preset corrosion weight loss calculation formula; and using the least squares method, performing multivariate function fitting on the voltage frequency, voltage amplitude, potential offset, and corrosion rate based on the test data set and the corresponding corrosion rate to obtain the mathematical evaluation model for the pipeline to be evaluated for corrosion.

[0032] The process involved conducting a corrosion weight loss test on metal specimens to obtain experimental data. Specifically, the test included: first, removing oil stains with acetone and cleaning with anhydrous ethanol before weighing the specimens to obtain their pre-corrosion mass; then, applying voltage signals of different frequencies, amplitudes, and offsets to the metal specimens and immersing them for 48 hours; after the corrosion weight loss immersion test, removing rust with a rust remover, cleaning with anhydrous ethanol, drying with a hair dryer, and weighing again to obtain the remaining mass after corrosion.

[0033] The formula for calculating corrosion weight loss is:

[0034]

[0035] In the formula, v is the corrosion rate, mm·a -1 Δm represents the weight loss, Δm = W1 - W2, where W1 is the mass before weight loss and W2 is the mass after weight loss, in grams; S represents the exposed area, in centimeters. 2 ρ is the material density, in g·cm³. -2 t represents the corrosion test time, in hours (h).

[0036] The frequency range of the dynamic stray DC current interference is 0–50 mHz, and the amplitude range of the interference voltage is 0.2 V–1.0 V. Experiments were conducted to investigate the effects of different interference voltage frequencies, amplitudes, and offsets on the pipeline corrosion rate. From the experimental data, the ranges of the dynamic stray DC current interference voltage frequency, amplitude, and offset under different corrosion severity levels were identified, which can then be converted into the corresponding corrosion severity levels of the pipeline under different interference current densities. The electrical parameter data set includes voltage frequency, voltage amplitude, and potential offset. The potential offset and voltage amplitude jointly affect the current density of the interference current; therefore, the interference current density can be used in place of the potential offset in the following text.

[0037] Based on experiments investigating the corrosion rate of test pieces under voltage interference of different frequencies, amplitudes, and offsets, the experimental data reveals the following mathematical relationships among the following factors: amplitudes of 0.2V, 0.4V, 0.6V, 0.8V, and 1.0V; frequencies of 10mHz, 20mHz, 30mHz, 40mHz, and 50mHz; interference current density (the combined effect of amplitude and offset, referred to as interference current density in this context); and corrosion rate. The corrosion rate of the test pieces increases with increasing interference voltage amplitude and exhibits a unidirectional change. Therefore, a unified mathematical model relating corrosion rate to frequency, current density, and amplitude can be obtained by fitting a multivariate function using the least squares method.

[0038] In one embodiment, the expression of the mathematical evaluation model is:

[0039] Y=87.53+17.59*X1-0.1661*X2+9.105*X3;

[0040] In the formula, Y represents the corrosion rate, and the unit is g / dm. 2 .a; X1 represents amplitude, in volts (V); X2 represents frequency, in mHz; X3 represents interference current density, in amperes (A / m). 2 GB / T 21447, "Code for External Corrosion Control of Steel Pipelines," provides a classification of pipeline corrosion rate severity: when the average corrosion rate is <1, the pipeline corrosion degree is weak; when the average corrosion rate is between 1 and 3, the pipeline corrosion degree is relatively weak; when the average corrosion rate is between 3 and 5, the pipeline corrosion degree is moderate; when the average corrosion rate is between 5 and 7, the pipeline corrosion degree is relatively strong; and when the average corrosion rate is >7, the pipeline corrosion degree is strong.

[0041] In the above process, a mathematical description of the corrosion rate and multiple factors was obtained through statistical mathematics. Although the accuracy was good, it did not provide a theoretical derivation from the perspective of corrosion mechanism. Therefore, the embodiments of the invention also focus on the corrosion mechanism, and from the perspective of physicochemical reaction and combined with the fitting formula results, to complete the physical and mathematical model of the corrosion rate and multiple factors.

[0042] Specifically, the theoretical expression for the corrosion rate of pipelines under dynamic stray DC interference is first calculated, and then the experimental results are fitted to the formula to approximate the theoretical expression.

[0043] In one embodiment, the mathematical evaluation model is modified using a preset Faraday correction formula to obtain a mathematical-physical evaluation model. Specifically, this includes: calculating a theoretical expression for the corrosion rate based on the preset Faraday correction formula; and modifying the mathematical evaluation model based on the theoretical expression for the corrosion rate to obtain the mathematical-physical evaluation model.

[0044] According to Faraday's law, the mass loss of steel under direct current can be calculated using the following formula:

[0045]

[0046] In the formula, m is the mass loss (g), i is the current density (A / cm2), t is the time (s), F is the Faraday constant (96485C / mol), and M is the molar mass of steel (55.85g / mol).

[0047] In one embodiment, the theoretical expression for the corrosion rate is:

[0048]

[0049] In the formula, T represents the fluctuation period in seconds, A represents the amplitude in volts (V), ω represents the angular frequency, y represents the phase, B represents the offset in volts (V), R represents the system resistance in ohms (Ω), F represents the Faraday constant (96485 C / mol), M is the molar mass of steel (55.85 g / mol), t represents the corrosion time in seconds, and m represents the amount of corrosion in grams.

[0050] In one embodiment, the mathematical physics evaluation model expression is:

[0051]

[0052] In the formula, V is the corrosion rate (g / cm). 2 ·s); F is the Faraday constant (96485C / mol); M is the molar mass of steel (55.85g / mol); K1 is the correction factor for the influence of corrosion products on the corrosion rate; K2 is the current correction factor caused by capacitance; A is the amplitude of the interference potential; B is the offset; C is the critical potential under the action of dynamic stray current; R is the resistance of the soil system.

[0053] The mathematical physics evaluation model can be integrated, and the result after integration is as follows:

[0054]

[0055] S3: Real-time acquisition of the voltage frequency, voltage amplitude, and potential offset of the pipeline to be corroded.

[0056] S4: Using the mathematical and physical evaluation model, corrosion assessment is performed on the pipeline to be assessed based on the voltage frequency, voltage amplitude, and potential offset.

[0057] After acquiring various data of the pipeline to be assessed for corrosion in real time, the data is input into the mathematical and physical evaluation model obtained in the aforementioned process to calculate the real-time corrosion rate. After averaging the real-time corrosion rate over a preset time period, the corresponding corrosion assessment result can be obtained based on the calculated average corrosion rate and the classification of the "Code for External Corrosion Control of Steel Pipelines".

[0058] Through the above steps, this embodiment of the invention obtains a mathematical model (statistical significance) for pipeline corrosion evaluation under dynamic DC stray current interference through statistical fitting regression, and obtains a mathematical model (physical significance) for pipeline corrosion evaluation through physical model analysis and data fitting. By substituting three key physical quantities—interference current density (or potential offset), potential fluctuation frequency, and potential amplitude—into the above two models, and combining them with the pipeline corrosion rate severity levels in GBT21447 "Code for External Corrosion Control of Steel Pipelines," the final classification of pipeline corrosion levels under dynamic DC stray current interference is obtained.

[0059] This invention describes a pipeline corrosion assessment method. A mathematical model for pipeline corrosion assessment under dynamic DC stray current interference is obtained through statistical fitting regression. A mathematical-physical evaluation model for pipeline corrosion is obtained by correcting the physical model and combining it with data fitting. When pipeline corrosion assessment is required, corrosion assessment is performed using the mathematical-physical evaluation model. This pipeline corrosion assessment method improves the accuracy of pipeline corrosion assessment and provides data support for pipeline safety management. Specific Implementation Example 2

[0061] In addition to the methods described above, this invention also discloses a pipeline corrosion assessment device. Figure 2 This is a schematic diagram of the structure of a pipeline corrosion assessment device provided in an embodiment of the present invention.

[0062] like Figure 2 As shown, the evaluation device includes a data acquisition unit 11, a modeling correction unit 12, and a corrosion evaluation unit 13.

[0063] The data acquisition unit 11 is used to acquire historical data of dynamic DC interference test of the pipeline to be evaluated for corrosion, and to acquire the voltage frequency, voltage amplitude and potential offset of the pipeline to be evaluated for corrosion in real time.

[0064] The modeling correction unit 12 is used to obtain the mathematical evaluation model of the pipeline to be corroded based on the historical data of the dynamic DC interference test by using a preset statistical fitting regression method, and to correct the mathematical evaluation model by using a preset Faraday correction formula to obtain a mathematical physical evaluation model.

[0065] In one embodiment, the modeling correction unit 13 is further configured to: set a test voltage according to a preset electrical parameter data set, and conduct a corrosion weight loss test on a metal specimen using the test voltage to obtain a test data set; the electrical parameter data set includes voltage frequency, voltage amplitude, and potential offset; calculate the corrosion rate corresponding to the electrical parameter data set based on the test data set and a preset corrosion weight loss calculation formula; and perform multivariate function fitting on the voltage frequency, voltage amplitude, potential offset, and corrosion rate using the least squares method based on the test data set and the corresponding corrosion rate to obtain a mathematical evaluation model for the pipeline to be evaluated for corrosion.

[0066] In one embodiment, the modeling correction unit 13 is further configured to: calculate the theoretical expression of corrosion rate according to a preset Faraday correction formula; and correct the mathematical evaluation model according to the theoretical expression of corrosion rate to obtain a mathematical physical evaluation model.

[0067] The corrosion evaluation unit 14 is used to evaluate the corrosion of the pipeline to be evaluated based on the voltage frequency, voltage amplitude and potential offset using the mathematical physics evaluation model.

[0068] If the integrated unit of the pipeline corrosion assessment device is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. Another embodiment of the present invention provides a computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the pipeline corrosion assessment method as described above.

[0069] The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium can include any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0070] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the device embodiments provided by this invention, the connection relationships between units indicate that they have communication connections, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0071] This invention describes a pipeline corrosion assessment device and a computer-readable storage medium. A mathematical model for pipeline corrosion assessment under dynamic DC stray current interference is obtained through statistical fitting regression. A mathematical-physical evaluation model for pipeline corrosion is obtained by correcting the physical model and combining it with data fitting. When pipeline corrosion assessment is required, corrosion assessment is performed using the mathematical-physical evaluation model. This pipeline corrosion assessment device and computer-readable storage medium improve the accuracy of pipeline corrosion assessment and provide data support for pipeline safety management. Specific Implementation Example 3

[0073] In addition to the methods and apparatus described above, embodiments of the present invention also describe a pipeline corrosion assessment system.

[0074] The evaluation system includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, which, when executing the computer program, implements the pipeline corrosion evaluation method as described above.

[0075] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the device, connecting various parts of the device via various interfaces and lines.

[0076] The memory can be used to store the computer programs and / or modules. The processor implements various functions of the device by running or executing the computer programs and / or modules stored in the memory and by calling data stored in the memory. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created according to the use of the mobile phone (such as audio data, phonebook, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0077] This invention describes a pipeline corrosion assessment system. A mathematical model for pipeline corrosion assessment under dynamic DC stray current interference is obtained through statistical fitting regression. A mathematical-physical assessment model for pipeline corrosion is obtained by correcting the physical model and combining it with data fitting. When pipeline corrosion assessment is required, the mathematical-physical assessment model is used for corrosion evaluation. This pipeline corrosion assessment system improves the accuracy of pipeline corrosion assessment and provides data support for pipeline safety management.

[0078] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for assessing pipeline corrosion, characterized in that, The evaluation method includes: Obtain historical dynamic DC interference test data for the pipeline to be evaluated for corrosion; Using a pre-defined statistical fitting regression method and based on the historical data of the dynamic DC interference test, a mathematical evaluation model for the pipeline to be evaluated for corrosion is obtained. This mathematical evaluation model is then corrected using a pre-defined Faraday correction formula to obtain a mathematical-physical evaluation model. Specifically, a theoretical expression for the corrosion rate is calculated based on the pre-defined Faraday correction formula. The mathematical evaluation model is then corrected based on this theoretical expression to obtain the mathematical-physical evaluation model. The expression for the mathematical evaluation model is as follows: Y=87.53+17.59*X1-0.1661*X2+9.105*X3; In the formula, Y represents the corrosion rate, and the unit is g / dm. 2 .a; X1 represents amplitude, in volts (V); X2 represents frequency, in mHz; X3 represents interference current density, in amperes (A / m). 2 The theoretical expression for the corrosion rate is: ； In the formula, T represents the fluctuation period in seconds (s), A represents the amplitude in volts (V), ω represents the angular frequency, y represents the phase, B represents the offset in volts (V), R represents the system resistance in ohms (Ω), F represents the Faraday constant (96485 C / mol), M is the molar mass of steel (55.85 g / mol), t represents the corrosion time in seconds (s), and m represents the corrosion amount in grams (g). The mathematical physics evaluation model expression is as follows: ; In the formula, V represents the corrosion rate, with units of g / cm³. 2 •s; F is the Faraday constant 96485 C / mol; M is the molar mass of steel 55.85 g / mol; K1 is the correction factor for the effect of corrosion products on corrosion rate; K2 is the current correction factor caused by capacitance; A is the amplitude of interference potential; B is the offset; C is the critical potential under the action of dynamic stray current; R is the resistance of the soil system. The voltage frequency, voltage amplitude, and potential offset of the pipeline to be evaluated for corrosion are acquired in real time. The corrosion assessment of the pipeline to be assessed is performed using the mathematical physics evaluation model based on the voltage frequency, voltage amplitude, and potential offset.

2. The pipeline corrosion assessment method according to claim 1, characterized in that, Using a pre-defined statistical fitting regression method, a mathematical evaluation model for the pipeline to be assessed for corrosion is obtained based on the historical data of the dynamic DC interference test. This model specifically includes: The test voltage is set according to the preset electrical parameter data set, and the metal specimen is subjected to corrosion weight loss test through the test voltage to obtain the test data set; the electrical parameter data set includes voltage frequency, voltage amplitude and potential offset; Based on the experimental data set and the preset corrosion weight loss calculation formula, calculate the corrosion rate corresponding to the electrical parameter data set; Using the least squares method, based on the experimental data set and the corresponding corrosion rate, a multivariate function fitting is performed on the voltage frequency, voltage amplitude, potential offset, and corrosion rate to obtain a mathematical evaluation model for the pipeline to be evaluated for corrosion.

3. A pipeline corrosion assessment device, characterized in that, The evaluation device includes a data acquisition unit, a modeling and correction unit, and a corrosion evaluation unit, wherein... The data acquisition unit is used to acquire historical data of dynamic DC interference test of the pipeline to be evaluated for corrosion, and to acquire the voltage frequency, voltage amplitude and potential offset of the pipeline to be evaluated for corrosion in real time. The modeling correction unit is used to obtain a mathematical evaluation model of the pipeline to be corroded based on the historical data of the dynamic DC interference test using a preset statistical fitting regression method, and to correct the mathematical evaluation model using a preset Faraday correction formula to obtain a mathematical-physical evaluation model; wherein, according to the preset Faraday correction formula, the theoretical expression of corrosion rate is calculated; and the mathematical evaluation model is corrected according to the theoretical expression of corrosion rate to obtain the mathematical-physical evaluation model; the expression of the mathematical evaluation model is: Y=87.53+17.59*X1-0.1661*X2+9.105*X3; In the formula, Y represents the corrosion rate, and the unit is g / dm. 2 .a; X1 represents amplitude, in volts (V); X2 represents frequency, in mHz; X3 represents interference current density, in amperes (A / m). 2 The theoretical expression for the corrosion rate is: ； In the formula, T represents the fluctuation period in seconds (s), A represents the amplitude in volts (V), ω represents the angular frequency, y represents the phase, B represents the offset in volts (V), R represents the system resistance in ohms (Ω), F represents the Faraday constant (96485 C / mol), M is the molar mass of steel (55.85 g / mol), t represents the corrosion time in seconds (s), and m represents the corrosion amount in grams (g). The mathematical physics evaluation model expression is as follows: ; In the formula, V represents the corrosion rate, with units of g / cm³. 2 •s; F is the Faraday constant 96485 C / mol; M is the molar mass of steel 55.85 g / mol; K1 is the correction factor for the effect of corrosion products on corrosion rate; K2 is the current correction factor caused by capacitance; A is the amplitude of interference potential; B is the offset; C is the critical potential under the action of dynamic stray current; R is the resistance of the soil system. The corrosion evaluation unit is used to evaluate the corrosion of the pipeline to be evaluated based on the voltage frequency, voltage amplitude, and potential offset using the mathematical physics evaluation model.

4. The pipeline corrosion assessment device according to claim 3, characterized in that, The modeling correction unit is also used for: The test voltage is set according to the preset electrical parameter data set, and the metal specimen is subjected to corrosion weight loss test through the test voltage to obtain the test data set; the electrical parameter data set includes voltage frequency, voltage amplitude and potential offset; Based on the experimental data set and the preset corrosion weight loss calculation formula, calculate the corrosion rate corresponding to the electrical parameter data set; Using the least squares method, based on the experimental data set and the corresponding corrosion rate, a multivariate function fitting is performed on the voltage frequency, voltage amplitude, potential offset, and corrosion rate to obtain a mathematical evaluation model for the pipeline to be evaluated for corrosion.

5. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the pipeline corrosion assessment method as described in any one of claims 1 to 2.

6. A pipeline corrosion assessment system, characterized in that, The evaluation system includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor executes the computer program to implement the pipeline corrosion evaluation method as described in any one of claims 1 to 2.

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