Method and system for evaluating corrosion state of inner wall of pipeline

Abstract

The application provides a pipeline inner wall corrosion state evaluation method and system, the method comprises the following steps: obtaining the corrosion type and specific service time of the pipeline inner wall to be evaluated; based on the corrosion type, a corresponding function relationship is obtained, the function relationship takes the service time of the pipeline as the independent variable and takes the self-corrosion current density of the pipeline as the dependent variable; based on the specific service time and the function relationship, the specific self-corrosion current density of the pipeline to be evaluated is calculated; the specific self-corrosion current density is compared with the preset maximum allowable self-corrosion current density, and the corrosion state of the pipeline to be evaluated is evaluated. It can be applied to the pipeline inner wall corrosion state evaluation of a specific corrosion type under a specific service time.

Description

Technical Field

[0001] This invention relates to the field of corrosion assessment technology, and in particular to a method and system for assessing the corrosion status of the inner wall of a pipeline. Background Technology

[0002] Traditional corrosion assessment methods mainly focus on metal equipment, oil and gas pipelines, and power transmission lines. In the field of metal corrosion detection, research on corrosion assessment of high-pressure air transmission pipelines for high-speed train braking systems is still lacking.

[0003] The probes of testing equipment such as magnetic leak detectors and ultrasonic detectors, which are widely used in fields such as pipe wall thickness measurement and pipeline defect detection, cannot enter the interior of the high-speed train brake steel pipe with an inner diameter of only 2cm. Therefore, they are not suitable for the research object of this invention. Furthermore, the phosphate film thickness on the inner wall of the high-speed train brake steel pipe is small. During long-term operation, the accumulation and shedding of corrosion products will lead to abnormal thickening and thinning of the pipe wall, respectively. Therefore, the use of magnetic leak detection and ultrasonic detection methods has considerable uncertainty and cannot accurately reflect the corrosion state inside the steel pipe.

[0004] The overall overhaul and maintenance of brake steel pipes for high-speed trains is a large-scale project. Current practice involves periodic shutdowns for inspection and maintenance. However, because it's impossible to quickly identify the most severely corroded pipes and predict their future corrosion status, the current maintenance process is somewhat inaccurate and delayed, leading to unnecessary economic losses and wasted manpower. Therefore, how to quantitatively and accurately assess corrosion status has become a core issue in the safe operation and management of high-speed trains.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the general background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a method and system for assessing the corrosion status of the inner wall of a pipeline.

[0007] This invention provides a method for assessing the corrosion status of the inner wall of a pipeline, the method comprising:

[0008] Obtain the type of corrosion and the specific service time of the inner wall of the pipeline to be evaluated;

[0009] Based on the corrosion type, the corresponding functional relationship is obtained, with the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable.

[0010] Based on the specific service time and the functional relationship, the specific self-corrosion current density of the pipeline to be evaluated is calculated.

[0011] The corrosion status of the pipeline to be evaluated is assessed by comparing the specific self-corrosion current density with the preset maximum allowable self-corrosion current density.

[0012] According to the present invention, a method for assessing the corrosion status of the inner wall of a pipeline is provided, which obtains the corrosion type and specific service time of the inner wall of the pipeline to be assessed, including:

[0013] Obtain the corrosion characteristics of the inner wall of the pipeline to be evaluated;

[0014] Based on the corrosion characteristics, the type of corrosion on the inner wall of the pipeline to be evaluated is determined.

[0015] According to the present invention, a method for assessing the corrosion status of the inner wall of a pipeline includes a method for obtaining the functional relationship:

[0016] Obtain multiple pipe samples with different service times for the corrosion type;

[0017] Multiple self-corrosion current densities of the multiple pipe samples were measured by potentiodynamic polarization testing.

[0018] Based on the service time and corresponding self-corrosion current density of the multiple pipe samples, the functional relationship is obtained by fitting.

[0019] According to the present invention, a method for assessing the corrosion state of a pipeline inner wall compares the specific self-corrosion current density with a preset maximum allowable self-corrosion current density to assess the corrosion state of the pipeline to be assessed, including:

[0020] If the specific self-corrosion current density is less than the preset maximum allowable self-corrosion current density, then a scanning electron microscope and / or an energy dispersive spectrometer and / or an X-ray diffractometer are used to obtain corrosion information.

[0021] Based on the corrosion information, the corrosion status of the pipeline to be evaluated is assessed.

[0022] According to the present invention, a method for assessing the corrosion status of the inner wall of a pipeline further includes:

[0023] Based on the maximum permissible self-corrosion current density and the functional relationship, the maximum service time is calculated;

[0024] Based on the specific service time and the maximum service time, it is determined whether the pipeline to be evaluated can continue to be in service, and the remaining service life of the pipeline to be evaluated is predicted.

[0025] According to the present invention, a method for assessing the corrosion status of the inner wall of a pipeline includes a corrosion type of uniform corrosion, and the corresponding functional relationship is a linear function.

[0026] According to the present invention, a method for assessing the corrosion status of the inner wall of a pipeline includes a corrosion type of pinhole corrosion, and the corresponding functional relationship is a quadratic function.

[0027] According to the present invention, a method for assessing the corrosion status of the inner wall of a pipeline includes corrosion types such as erosion corrosion, and the corresponding functional relationship is an exponential function.

[0028] According to the present invention, a method for assessing the corrosion status of the inner wall of a pipeline is provided, wherein the pipeline to be assessed includes a high-speed train brake steel pipe.

[0029] This invention also provides a pipeline inner wall corrosion status assessment system, the system comprising:

[0030] The first acquisition module is used to acquire the corrosion type and specific service time of the inner wall of the pipeline to be evaluated;

[0031] The second acquisition module is used to acquire the corresponding functional relationship based on the corrosion type, wherein the functional relationship takes the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable.

[0032] The calculation module is used to calculate the specific self-corrosion current density of the pipeline to be evaluated based on the specific service time and the functional relationship.

[0033] The evaluation module is used to compare the specific self-corrosion current density with the preset maximum allowable self-corrosion current density to evaluate the corrosion status of the pipeline to be evaluated.

[0034] The pipeline internal wall corrosion status assessment method and system provided by the present invention can be applied to assess the pipeline internal wall corrosion status of specific corrosion types under specific service time. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in this 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 some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0036] Figure 1 A schematic flowchart of a method for assessing the corrosion status of the inner wall of a pipeline provided by the present invention;

[0037] Figure 2 A three-electrode system test circuit diagram provided by the present invention;

[0038] Figure 3This is a schematic diagram of fitting the functional relationship of the uniformly corroded steel pipe provided by the present invention;

[0039] Figure 4 This is a schematic diagram of the fitting of the functional relationship of the steel pipe with pinhole corrosion provided by the present invention;

[0040] Figure 5 This is a schematic diagram of fitting the functional relationship of the erosion corrosion of the steel pipe provided by the present invention;

[0041] Figure 6 A schematic diagram of a pipeline inner wall corrosion status assessment system provided by the present invention;

[0042] Figure 7 This is a schematic diagram of the physical structure of an electronic device provided by the present invention. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0044] The method for assessing the corrosion status of the inner wall of a pipeline provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0045] Figure 1 A flowchart illustrating a method for assessing the corrosion status of a pipeline inner wall provided by this invention is shown below. Figure 1 As shown, the present invention provides a method for assessing the corrosion status of the inner wall of a pipeline, the method comprising the following steps.

[0046] S100. Obtain the corrosion type and specific service time of the inner wall of the pipeline to be evaluated.

[0047] Optionally, the pipeline to be evaluated includes high-speed train brake steel pipes. It should be noted that this invention is applicable to high-speed train brake steel pipes with extremely small diameters, complex pipelines, and difficult-to-lay monitoring equipment. It can perform real-time inspections on steel pipes that have been in service for a certain period, and can also predict corrosion development over the next few years. Furthermore, this invention is also applicable to the evaluation of other pipelines with extremely small diameters, complex pipelines, and difficult-to-lay monitoring equipment.

[0048] Furthermore, the corrosion state of the phosphate film on the inner wall of the EMU brake steel pipe is taken as the evaluation object of this method.

[0049] Optionally, obtain the corrosion type and specific service time of the inner wall of the pipe to be evaluated, including:

[0050] Obtain the corrosion characteristics of the inner wall of the pipe to be evaluated;

[0051] Based on corrosion characteristics, determine the type of corrosion on the inner wall of the pipeline to be evaluated.

[0052] Optionally, the corrosion type includes: uniform corrosion, and the corresponding functional relationship is a linear function.

[0053] Optionally, the corrosion type includes: pitting corrosion, and the corresponding functional relationship is a quadratic function.

[0054] Optionally, the corrosion type includes erosion corrosion, and the corresponding functional relationship is an exponential function.

[0055] Preferably, based on corrosion characteristics, the type of corrosion on the inner wall of the pipe to be evaluated is determined, including:

[0056] If the following characteristics are observed: the main body of the phosphate film on the inner wall of the steel pipe is gray, with only light yellow to light red hazy corrosion, and no obvious dotted or streaky rust, it can be inferred that the ambient temperature and pressure of the pipeline are relatively stable during operation, water vapor does not easily condense into water droplets, and a humid acidic environment has not been formed; acidic oxides in the air react slowly with the base metal at the defects in the phosphate film, forming a single chemical corrosion; in summary, it is determined that the steel pipe with the above corrosion characteristics has formed uniform corrosion.

[0057] If the following characteristics are observed: localized reddish-brown dot-like corrosion pits or circular corrosion spots on the inner wall of the steel pipe, mainly concentrated on one side of the pipe, it is inferred that the pipe temperature and pressure frequently change during operation, causing water vapor to condense on one side under gravity, forming circular water droplets; acidic oxides in the air dissolve in the condensate, creating an acidic environment that reacts first with the metal substrate at the defects in the film layer. The metal easily loses electrons to form a micro-anode, but at this time the phosphating film remains regular, acting as a cathode over a large area. The two constitute an electrochemical system of "small anode and large cathode," continuously deepening the corrosion pits; in summary, steel pipes exhibiting the above corrosion characteristics are considered to have pitting corrosion.

[0058] If the following characteristics are observed: large areas of dark red to brownish-red irregular striped rust are distributed on the inner wall of the steel pipe, corrosion products accumulate and detach, and some silvery-white substrate is exposed; then it is inferred that the pipeline has been under high-pressure air supply conditions for a long time during operation, resulting in severe scouring; in the early stage of corrosion, scouring accelerates corrosion mass transfer and promotes the formation of an acidic environment; in the later stage of corrosion, scouring removes corrosion products, the main body of the phosphate film is damaged, resulting in the exposure of the metal substrate and an accelerated corrosion rate; in addition, moisture and acidic oxides in the air trigger chemical corrosion and electrochemical corrosion, forming a synergistic effect with scouring; in summary, the steel pipe with the above corrosion characteristics is determined to have scouring corrosion.

[0059] It should be noted that the above-mentioned acquisition of the corrosion type of the inner wall of the pipeline to be evaluated can be based on manual observation or on various detection information of the inner wall obtained by sensing devices. Furthermore, based on the detection information, a type judgment model is used to determine the specific corrosion type. In addition, the detection information includes image information, and the type judgment model includes neural networks.

[0060] S200. Based on the corrosion type, obtain the corresponding functional relationship. The functional relationship uses the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable.

[0061] Optionally, methods for obtaining the functional relation include:

[0062] Obtain multiple pipeline samples with different corrosion types and service times;

[0063] Multiple self-corrosion current densities of multiple pipe samples were measured by potentiodynamic polarization testing.

[0064] Based on the service time and corresponding self-corrosion current density of multiple pipeline samples, a functional relationship was obtained by fitting.

[0065] It should be noted that selecting the corresponding functional relationship based on the type of corrosion of the steel pipe can help assessors quickly understand the corrosion development trend.

[0066] Preferably, multiple pipe samples with different corrosion types and service times are obtained, including:

[0067] 1) Steel pipe sampling - Sample pipes with service times of 3 years, 5 years, 8 years and 10 years were taken as the main research objects, and samples pipes that were not put into service and samples that were taken out of service were taken as controls. The steel pipes that were taken out of service refer to steel pipes that were determined to no longer be able to continue to serve on vehicles and were replaced.

[0068] 2) Steel pipe cutting - Use a high-speed cutting machine to evenly cut open a steel pipe with an inner diameter of about 20mm and a wall thickness of about 2mm.

[0069] 3) Surface cleaning – Remove metal debris and burrs generated during the steel pipe cutting process.

[0070] 4) Corrosion classification – Record corrosion characteristics, determine corrosion type, and classify steel pipes with different corrosion types (mainly including uniform corrosion, pitting corrosion, and erosion corrosion).

[0071] 5) Steel pipe naming – The steel pipes under investigation are grouped and named according to their service time. Uniform corrosion is named J-3, J-5, J-8, and J-10; pinhole corrosion is named X-3, X-5, X-8, and X-10; and erosion corrosion is named C-3, C-5, C-8, and C-10. Sample pipes not yet in service and those already out of service are named W and Y, respectively.

[0072] Preferably, multiple self-corrosion current densities of multiple pipe samples are measured through potentiodynamic polarization testing, including:

[0073] 1) Electrode Preparation – The aforementioned steel pipe was cut into semi-circular test pieces, 1 cm wide and 2 cm in inner diameter. The outer wall was sanded to remove the insulating paint. A copper wire was soldered onto the outer wall of the steel pipe. Both the outer wall of the steel pipe and the connection point of the copper wire were sealed with epoxy resin. The other end of the copper wire served as a connector. After the epoxy resin cured, anhydrous ethanol was used to remove grease from the sample surface. The sample was then dried at room temperature and used as a working electrode. Figure 2 A three-electrode system test circuit diagram provided by the present invention, such as Figure 2 As shown, reference electrode 3 is a saturated calomel electrode, and auxiliary electrode 1 is a platinum electrode. A standard three-electrode electrolytic cell is used, with a 3.5% sodium chloride solution as the electrolyte. The working electrode (i.e., the aforementioned cut and polished steel tube 2), reference electrode 3, and auxiliary electrode 1 are connected to the working electrode line, auxiliary electrode line, and reference electrode line of the electrochemical workstation, respectively.

[0074] 2) Potentiodynamic polarization test—Under room temperature conditions, the open-circuit potential of the working electrode is measured. The scan rate is set to 10 mV / s, and the potentiodynamic polarization curve of the electrode is tested within the range of ±0.5 V from the open-circuit potential. The corrosion current density (unit: A·cm) is obtained by fitting. -2 First, the self-corrosion current density of the un-connected and disconnected sample tubes was measured and used as the initial self-corrosion current density (9.9·10-7 A·cm). -2 ) and the maximum permissible self-corrosion current density (1.4·10-7A·cm) -2 ).

[0075] Preferably, based on the service time of multiple pipe samples and the corresponding multiple self-corrosion current densities, a functional relationship is fitted to obtain the following:

[0076] 1) Establish a database – Measure the self-corrosion current density corresponding to all the named steel pipes mentioned above, and use the self-corrosion current density of steel pipes that have not been put into service and steel pipes that have been taken out of service as a reference to screen out data that deviate significantly from the normal range.

[0077] 2) Function Fitting – Plot an XY scatter plot with service time as the x-axis (X) and self-corrosion current density as the y-axis (Y), and use the least squares method to fit the function relationship. Uniform corrosion, pitting corrosion, and erosion corrosion conform to linear, quadratic, and logarithmic functions, respectively, within a certain service time range, as shown in Table 1 below.

[0078] Uniform corrosion <![CDATA[Y=4·10 -7 X+1·10 -6 ]]> Pitting corrosion <![CDATA[Y=2·10 -7 X 2 -1·10 -6 X+2·10 -6 ]]> Erosion and corrosion <![CDATA[Y=8·10 -7 ·and 0.2542X ]]>

[0079] Table 1

[0080] Figure 3 This is a schematic diagram of the fitting of the functional relationship of uniformly corroded steel pipes provided by the present invention, as shown in the figure. Figure 3 As shown, the uniformly corroded steel pipe, including the tread cleaning pipe, has its self-corrosion current density and service time scatter plot finally yielding the fitting function Y = 4.10. -7 X+1·10 -6 In addition, the self-corrosion current density of steel pipes under different service years can also be referred to Table 2 below.

[0081]

[0082] Table 2

[0083] Figure 4 This is a schematic diagram of the fitting of the functional relationship of the steel pipe with pinhole corrosion provided by the present invention, as shown in the figure. Figure 4 As shown, the steel pipe with pitting corrosion, including the brake main pipe, has its self-corrosion current density and service time scatter plot finally yielding the fitting function Y = 2.10. -7 X 2 -1·10 -6 X+2·10 -6 In addition, the self-corrosion current density of steel pipes under different service years can also be referred to Table 3 below.

[0084]

[0085] Table 3

[0086] Figure 5 This is a schematic diagram of the fitting of the functional relationship of the steel pipe subjected to erosion corrosion provided by the present invention, as shown in the figure. Figure 5 As shown, the steel pipes subjected to erosion corrosion include MR pipes such as those at BCU. The scatter plot of its self-corrosion current density and service time ultimately yields the fitting function Y = 8.10. -7 ·e 0.2542X In addition, the self-corrosion current density of steel pipes under different service years can also be referred to Table 4 below.

[0087]

[0088] Table 4

[0089] By looking up tables, assessors can quickly find the required self-corrosion current density based on the service time.

[0090] S300, based on the specific service time and functional relationship, calculates the specific self-corrosion current density of the pipeline to be evaluated.

[0091] Preferably, the specific service time of the independent variable (X) is input into the functional relationship, and the self-corrosion current density corresponding to the dependent variable (Y) is output.

[0092] It should be noted that the self-corrosion current density value can quantitatively and intuitively reflect the corrosion status of steel pipes with different corrosion types over a specific number of years.

[0093] S400. Compare the specific self-corrosion current density with the preset maximum allowable self-corrosion current density to assess the corrosion status of the pipeline to be evaluated.

[0094] Optionally, the specific self-corrosion current density is compared with the preset maximum allowable self-corrosion current density to assess the corrosion state of the pipeline under evaluation, including:

[0095] If the specific self-corrosion current density is less than the preset maximum allowable self-corrosion current density, then scanning electron microscopy (SEM), and / or energy dispersive spectroscopy (EDS), and / or X-ray diffraction (XRD) are used to obtain corrosion information.

[0096] Based on corrosion information, assess the corrosion status of the pipeline to be evaluated.

[0097] Preferably, the corrosion state of the pipeline under evaluation is assessed by comparing the specific self-corrosion current density with the preset maximum allowable self-corrosion current density, including:

[0098] If the specific self-corrosion current density is greater than or equal to the preset maximum allowable self-corrosion current density, the pipeline to be evaluated is determined to be unable to continue service, and the remaining service life is 0.

[0099] Preferably, assessing the corrosion status of the pipeline to be assessed includes:

[0100] By combining scanning electron microscopy (SEM), and / or energy dispersive spectroscopy (EDS), and / or X-ray diffraction (XRD), and / or steel pipe thickness measurement instruments to obtain the characterization of the inner wall of the steel pipe, the accuracy of the corrosion status assessment method is improved, potential economic losses and safety hazards are reduced, and finally, it is determined whether to take repair or replacement measures and to formulate a feasible operation plan.

[0101] This embodiment can be applied to assess the corrosion status of the inner wall of a pipeline with a specific corrosion type under a specific service time.

[0102] Optionally, based on the foregoing embodiments, in another embodiment, the method further includes:

[0103] The maximum service time is calculated based on the maximum permissible self-corrosion current density and the functional relationship.

[0104] Based on the specific service time and maximum service time, determine whether the pipeline under evaluation can continue to be in service, and predict the remaining service life of the pipeline under evaluation.

[0105] It should be noted that this invention can estimate the maximum service time corresponding to different corrosion types, so as to take timely measures to repair or replace the steel pipe and prevent operational failures that may be caused by the accumulation of corrosion products.

[0106] This embodiment establishes a functional relationship between corrosion current density and service time, which can serve as a simple means of assessing the corrosion status of brake steel pipes in high-speed trains, and also as a rapid method for predicting the service life of steel pipes. This method can both avoid the risks caused by the continuous aggravation of corrosion of steel pipes under long-term service conditions and maximize the normal operation time of the high-speed train.

[0107] The following describes the pipeline internal wall corrosion status assessment system provided by the present invention. The pipeline internal wall corrosion status assessment system described below can be referred to in correspondence with the pipeline internal wall corrosion status assessment method described above.

[0108] Figure 6 A schematic diagram of a pipeline inner wall corrosion status assessment system provided by the present invention is shown below. Figure 6 As shown, the present invention also provides a pipeline inner wall corrosion status assessment system, the system comprising:

[0109] The first acquisition module is used to acquire the corrosion type and specific service time of the inner wall of the pipeline to be evaluated;

[0110] The second acquisition module is used to obtain the corresponding functional relationship based on the corrosion type. The functional relationship takes the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable.

[0111] The calculation module is used to calculate the specific self-corrosion current density of the pipeline to be evaluated based on the specific service time and functional relationship.

[0112] The evaluation module is used to compare the specific self-corrosion current density with the preset maximum allowable self-corrosion current density to assess the corrosion status of the pipeline to be evaluated.

[0113] This embodiment can be applied to assess the corrosion status of the inner wall of a pipeline with a specific corrosion type under a specific service time.

[0114] Figure 7A schematic diagram of the physical structure of an electronic device provided by the present invention, such as... Figure 7 As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830, and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other via the communication bus 840. The processor 810 can call logical instructions in the memory 830 to execute a method for assessing the corrosion status of the inner wall of a pipeline, the method including:

[0115] Obtain the type of corrosion and the specific service time of the inner wall of the pipeline to be evaluated;

[0116] Based on the corrosion type, the corresponding functional relationship is obtained, with the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable.

[0117] Based on the specific service time and the functional relationship, the specific self-corrosion current density of the pipeline to be evaluated is calculated.

[0118] The corrosion status of the pipeline to be evaluated is assessed by comparing the specific self-corrosion current density with the preset maximum allowable self-corrosion current density.

[0119] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, 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.

[0120] On the other hand, the present invention also provides a computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, wherein when the program instructions are executed by a computer, the computer is able to execute the pipeline inner wall corrosion status assessment method provided by the above methods, the method comprising:

[0121] Obtain the type of corrosion and the specific service time of the inner wall of the pipeline to be evaluated;

[0122] Based on the corrosion type, the corresponding functional relationship is obtained, with the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable.

[0123] Based on the specific service time and the functional relationship, the specific self-corrosion current density of the pipeline to be evaluated is calculated.

[0124] The corrosion status of the pipeline to be evaluated is assessed by comparing the specific self-corrosion current density with the preset maximum allowable self-corrosion current density.

[0125] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the aforementioned methods for assessing the corrosion status of the inner wall of a pipe, the methods comprising:

[0126] Obtain the type of corrosion and the specific service time of the inner wall of the pipeline to be evaluated;

[0127] Based on the corrosion type, the corresponding functional relationship is obtained, with the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable.

[0128] Based on the specific service time and the functional relationship, the specific self-corrosion current density of the pipeline to be evaluated is calculated.

[0129] The corrosion status of the pipeline to be evaluated is assessed by comparing the specific self-corrosion current density with the preset maximum allowable self-corrosion current density.

[0130] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. 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. Those skilled in the art can understand and implement this without any creative effort.

[0131] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for assessing the corrosion status of the inner wall of a pipeline, characterized in that, The method includes: Obtain the type of corrosion and the specific service time of the inner wall of the pipeline to be evaluated; Based on the corrosion type, the corresponding functional relationship is obtained, with the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable. The corrosion types include: Uniform corrosion, correspondingly, the functional relationship is a linear function; For pinhole corrosion, the corresponding functional relationship is a quadratic function; Erosion and corrosion, correspondingly, the functional relationship is an exponential function; Based on the corrosion type, selecting the corresponding functional relationship can help assessors quickly understand the corrosion development trend. Based on the specific service time and the functional relationship, the specific self-corrosion current density of the pipeline to be evaluated is calculated. The corrosion status of the pipeline to be evaluated is assessed by comparing the specific self-corrosion current density with the preset maximum allowable self-corrosion current density.

2. The method for assessing the corrosion status of the inner wall of a pipeline according to claim 1, characterized in that, Obtain the type of corrosion and the specific service time of the inner wall of the pipe to be evaluated, including: Obtain the corrosion characteristics of the inner wall of the pipeline to be evaluated; Based on the corrosion characteristics, the type of corrosion on the inner wall of the pipeline to be evaluated is determined.

3. The method for assessing the corrosion status of the inner wall of a pipeline according to claim 1, characterized in that, The method for obtaining the functional relation includes: Obtain multiple pipe samples with different service times for the corrosion type; Multiple self-corrosion current densities of the multiple pipe samples were measured by potentiodynamic polarization testing. Based on the service time and corresponding self-corrosion current density of the multiple pipe samples, the functional relationship is obtained by fitting.

4. The method for assessing the corrosion status of the inner wall of a pipeline according to claim 1, characterized in that, The corrosion state of the pipeline under evaluation is assessed by comparing the specific self-corrosion current density with the preset maximum allowable self-corrosion current density, including: If the specific self-corrosion current density is less than the preset maximum allowable self-corrosion current density, then a scanning electron microscope and / or an energy dispersive spectrometer and / or an X-ray diffractometer are used to obtain corrosion information. Based on the corrosion information, the corrosion status of the pipeline to be evaluated is assessed.

5. The method for assessing the corrosion status of the inner wall of a pipeline according to claim 1, characterized in that, The method further includes: Based on the maximum permissible self-corrosion current density and the functional relationship, the maximum service time is calculated; Based on the specific service time and the maximum service time, it is determined whether the pipeline to be evaluated can continue to be in service, and the remaining service life of the pipeline to be evaluated is predicted.

6. The method for assessing the corrosion status of the inner wall of a pipeline according to claim 1, characterized in that, The pipelines to be evaluated include the brake steel pipes for high-speed trains.

7. A system for assessing the corrosion status of a pipeline inner wall, characterized in that, The system, employing the pipeline internal wall corrosion status assessment method as described in any one of claims 1-6, comprises: The first acquisition module is used to acquire the corrosion type and specific service time of the inner wall of the pipeline to be evaluated; The second acquisition module is used to acquire the corresponding functional relationship based on the corrosion type, wherein the functional relationship takes the service time of the pipeline as the independent variable and the self-corrosion current density of the pipeline as the dependent variable. The calculation module is used to calculate the specific self-corrosion current density of the pipeline to be evaluated based on the specific service time and the functional relationship. The evaluation module is used to compare the specific self-corrosion current density with the preset maximum allowable self-corrosion current density to evaluate the corrosion status of the pipeline to be evaluated.

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