Method and system for evaluating failure risk of buried pipeline in geological disaster area

Abstract

The invention discloses a method and system for evaluating the failure risk of a buried pipeline in a disaster area, and the method comprises the steps: dividing a target pipeline into a plurality of segments, and determining a plurality of segments of to-be-evaluated pipelines; the total probability of leakage risks caused by the internal corrosion risk and the ground disaster risk of each to-be-evaluated pipeline is calculated, so that the failure possibility of the corresponding pipeline is obtained; determining the severity of the leakage risk consequence of each section of the to-be-evaluated pipeline; and determining the risk level of the corresponding pipeline according to the failure possibility and the leakage risk consequence severity of each section of to-be-evaluated pipeline. According to the invention, pertinence of failure risk assessment of the buried pipeline in the disaster area can be enhanced, and the level of safe operation management and technology of the buried pipeline is improved.

Description

Technical Field

[0001] The present invention relates to the field of pipeline safety risk assessment, and in particular to a method and system for assessing the failure risk of buried pipelines in disaster-stricken areas. Background Art

[0002] With the continuous development of my country's national economy, the energy structure is also being optimized. As a clean and environmentally friendly high-quality energy, natural gas is increasingly valued. Natural gas has gradually occupied a pivotal position in my country's energy structure, and its consumption has continued to rise sharply. In order to ensure the supply of natural gas, my country has continued to increase its efforts in natural gas exploration and development in recent years. At present, the scale of my country's natural gas pipeline network continues to expand. Gas field gathering and transportation pipelines, natural gas long-distance pipelines and urban natural gas pipelines have jointly formed a "trunk interconnection and local network" pattern, with a total mileage of more than 1 million kilometers. Among them, although the proportion of gas field gathering and transportation pipelines is relatively small, due to its complex external environment and harsh internal working conditions, natural gas leakage accidents in gas field gathering and transportation pipelines occur from time to time. If they are not discovered and properly handled in time, they are very likely to cause fires or explosions, posing a great threat to the safe production of enterprises and people's lives and property.

[0003] In recent years, Sichuan and Chongqing have gradually become one of the main battlefields for oil and gas production in my country. Oil and gas fields are constantly being discovered and developed on a large scale. Since Sichuan and Chongqing are located in mountainous areas and have heavy rainfall, they have also become the hardest hit areas of geological disasters in my country. According to statistics, geological disasters such as landslides and mudslides in Sichuan and Chongqing account for about 14% of the same type of geological disasters in the country. Geological disasters may cause geological changes and ground subsidence, which in turn may cause the joints of natural gas pipelines to loosen and cause natural gas leaks. In addition, the construction of buried pipelines in the geological disaster areas within Sichuan and Chongqing also faces the risk of natural gas leaks caused by widespread corrosion perforation.

[0004] In response to the above problems, there are many methods applied to natural gas pipeline failure:

[0005] In the prior art CN102156089A, a method for evaluating internal corrosion of a buried pipeline is provided, which comprises: a pre-evaluation step of internal corrosion detection of a buried pipeline; an indirect detection and evaluation step of internal corrosion of a buried pipeline; a direct detection and evaluation step of internal corrosion of a buried pipeline; an effectiveness evaluation step of a direct evaluation ICDA of internal corrosion of a buried pipeline and a step of determining a time for re-evaluation, thereby improving the level of safe operation management and technology of buried pipelines, reducing the economic losses of personnel and facilities caused by sudden accidents, and ensuring safe production.

[0006] In the prior art CN114723218A, a method for evaluating geological hazards of natural gas pipelines based on information volume-neural network is disclosed, which includes the following steps: determining the study area and dividing the grid units; conducting a geological hazard susceptibility assessment; conducting a pipeline vulnerability assessment; dividing the standards according to the failure consequences and determining the level of the failure consequences; and determining the risk level of pipeline geological hazards using the pipeline failure probability and the level of the failure consequences.

[0007] However, the existing technology only considers one kind of risk to establish the calculation model and risk assessment method, and does not give in-depth consideration to the dual coupling risks of corrosion and geological disasters faced by buried pipelines in geological disaster areas.

[0008] Therefore, in order to ensure the safe and stable operation of buried natural gas pipelines in geological disaster areas and realize the effective assessment, monitoring and early warning of the dual coupling risks of corrosion / geological disasters, the present invention needs to establish a failure probability calculation model and quantitative assessment method for natural gas pipelines in geological disaster areas. Summary of the invention

[0009] The present invention aims to address the problem that traditional technologies fail to simultaneously consider the leakage and failure of pipelines caused by corrosion and geological disasters, and propose a technical solution for evaluating the failure risk of buried pipelines in geological disaster areas.

[0010] In order to solve the above technical problems, an embodiment of the present invention provides a method for evaluating the failure risk of buried pipelines in geological disaster areas, including: step 1, dividing the target pipeline into multiple sections, and determining multiple sections of pipelines to be evaluated; step 2, calculating the total probability of leakage risk caused by internal corrosion and geological disaster risks of each section of the pipeline to be evaluated, so as to obtain the failure possibility of the corresponding pipeline; step 3, determining the severity of the consequences of the leakage risk of each section of the pipeline to be evaluated; step 4, determining the risk level of the corresponding pipeline according to the failure possibility and the severity of the consequences of the leakage risk of each section of the pipeline to be evaluated.

[0011] Preferably, the second step includes: respectively calculating the small hole internal corrosion leakage risk probability, the medium hole internal corrosion leakage risk probability and the fracture internal corrosion leakage risk probability caused by internal corrosion of each section of the pipeline to be evaluated, based on which, the total probability of internal corrosion leakage risk of each section of the pipeline to be evaluated is obtained; respectively calculating the small hole geological disaster leakage risk probability, the medium hole geological disaster leakage risk probability and the fracture geological disaster leakage risk probability caused by geological disasters of each section of the pipeline to be evaluated, based on which, the total probability of geological disaster leakage risk of each section of the pipeline to be evaluated is obtained; according to the total probability of internal corrosion leakage risk and the total probability of geological disaster leakage risk of each section of the pipeline to be evaluated, the total probability of pipeline leakage risk of the corresponding section is obtained, thereby obtaining the failure possibility of the corresponding section of the pipeline.

[0012] Preferably, in the process of calculating the total probability of internal corrosion leakage risk of each section of the pipeline to be evaluated, the process includes: determining the internal detection time correction factor according to the initial effectiveness of the internal detection of the pipeline to be evaluated, the internal detection execution time, the internal detection time increment, and the internal detection validity period, and calculating the effective years of internal corrosion according to the internal detection time correction factor in combination with the pipeline operation years and the internal detection time increment; determining the gathering medium corrosiveness factor according to the electrical fingerprint corrosion rate of the pipeline to be evaluated; calculating the internal corrosion leakage risk probability of different failure forms in the pipeline to be evaluated according to the effective years of internal corrosion of the pipeline to be evaluated and the gathering medium corrosiveness factor in combination with the internal corrosion leakage risk baseline probability, the internal corrosion leakage risk model proportional coefficient, the pipeline wall thickness, the internal corrosion leakage degree correction factor of different failure forms and the pipeline length; and determining the sum of the small hole internal corrosion leakage risk probability, the medium hole internal corrosion leakage risk probability and the fracture internal corrosion leakage risk probability as the total probability of internal corrosion leakage risk of the pipeline to be evaluated.

[0013] Preferably, the internal corrosion leakage risk probability of different failure modes is expressed by the following expression:

[0014] R 内腐蚀 =RB 内腐蚀 ×K 内腐蚀 ×(τ 内腐蚀 / t)×FPC×k×L

[0015] Among them, R 内腐蚀 Represents the risk probability of corrosion leakage in the pipeline, RB 内腐蚀 represents the baseline probability of corrosion leakage risk in the pipeline, K 内腐蚀 represents the proportional coefficient of the internal corrosion leakage risk model; τ 内腐蚀 represents the effective life of internal corrosion of pipelines, t represents the wall thickness of pipelines, FPC represents the corrosiveness factor of gathering and transportation media, k represents the leakage degree correction factor of different failure forms, and L represents the length of pipelines. The effective life of internal corrosion is represented by the following expression:

[0016] τ 内腐蚀 =λ×(τ a +Δτ)

[0017]

[0018] Among them, λ represents the internal detection time correction factor, β represents the initial effectiveness of the pipeline internal detection, and τ a represents the operating life of the pipeline, Δτ represents the time increment, and τ b represents the validity period of the in-pipeline detection, τ l Indicates the execution time of corrosion detection.

[0019] Preferably, the internal corrosion leakage correction factors of small holes, medium holes and fractures are 0.85, 0.1 and 0.05 respectively; and the corresponding relationship between the electric fingerprint corrosion rate and the gathering and transportation medium corrosive factor is: when the electric fingerprint corrosion rate is less than 0.02, the gathering and transportation medium corrosive factor is 0.04; when the electric fingerprint corrosion rate is greater than or equal to 0.02 and less than 0.1, the gathering and transportation medium corrosive factor is 0.2; when the electric fingerprint corrosion rate is greater than or equal to 0.1 and less than 0.5, the gathering and transportation medium corrosive factor is 1.0; when the electric fingerprint corrosion rate is greater than or equal to 0.5 and less than 2.5, the gathering and transportation medium corrosive factor is 5.0; when the electric fingerprint corrosion rate is greater than or equal to 2.5, the gathering and transportation medium corrosive factor is 6.0.

[0020] Preferably, in the process of calculating the total probability of geological disaster leakage risk of each section of the pipeline to be evaluated, the process includes: determining the corresponding geological disaster warning coefficient according to the geological disaster warning level of the pipeline to be evaluated; determining the pipeline failure frequency according to the pipeline failure level of the pipeline to be evaluated; determining the pipeline connection coefficient according to the pipeline weld quality level of the pipeline to be evaluated; calculating the geological disaster leakage risk probability of different failure forms in the pipeline to be evaluated according to the geological disaster warning coefficient, pipeline failure frequency and pipeline connection coefficient of the pipeline to be evaluated, combined with the geological disaster pipeline failure risk baseline probability, the geological disaster leakage degree correction factor of different failure forms and the pipeline length; and determining the sum of the small hole geological disaster leakage risk probability, the medium hole geological disaster leakage risk probability and the fracture geological disaster leakage risk probability as the total probability of geological disaster leakage risk of the pipeline to be evaluated.

[0021] Preferably, the risk probability of geological disaster leakage in different failure modes is expressed by the following expression:

[0022] R 地灾 =RB 地灾 ×FYJ×RP 管道失效 ×FJNT×a×L

[0023] Among them, R 地灾 represents the probability of pipeline geological disaster leakage risk, RB 地灾 represents the baseline probability of pipeline geological disaster leakage risk, FYJ represents the geological disaster warning coefficient, RP 管道失效 represents the pipeline failure frequency, FJNT represents the pipeline connection coefficient, a represents the leakage degree correction factor, and L represents the pipeline length.

[0024] Preferably, the correction factors for the geological disaster leakage degree of small holes, medium holes and fractures are 0.2, 0.4 and 0.5 respectively; when the geological disaster warning levels are attention level, warning level, alert level and alarm level from low to high, the corresponding geological disaster warning coefficients are 0.5, 1, 1.5 and 2 respectively; when the pipeline failure levels are low failure level, medium failure level and high failure level from low to high, the corresponding pipeline failure frequencies are 0.01, 0.1 and 1 respectively; when the pipeline weld quality levels are high quality weld, medium quality weld, general quality weld and mechanical connection from high to low, the corresponding pipeline connection coefficients are 0.1, 1.0, 4.0 and 8.0 respectively.

[0025] Preferably, in the process of determining the severity of the consequences of the leakage risk of each section of the pipeline to be evaluated, the process includes: determining the radius of the potential impact area of ​​the current pipeline according to the maximum operating pressure of the pipeline to be evaluated and the pipeline specifications, wherein the radius of the current potential impact area is calculated using the following expression:

[0026]

[0027] Where r represents the affected radius, d represents the outer diameter of the pipeline, and p represents the maximum allowable operating pressure of the pipe section. The casualties within the radius of the current potential impact area are counted to determine the corresponding severity level of the consequences.

[0028] Preferably, the target pipeline is divided into multiple sections of primary pipelines with the shutoff valve chamber as a dividing point; the pipelines laid in the form of crossing and spanning in each section of the primary pipeline are removed, so as to retain the pipelines laid in the form of buried in each section of the primary pipeline, so as to form multiple sections of pipelines to be evaluated.

[0029] Preferably, in the process of eliminating each section of primary pipeline according to different laying methods, if there are multiple discontinuous pipe sections in the same section of primary pipeline, these discontinuous pipe sections are regarded as multiple sections of pipeline to be evaluated; if there is only one section of pipeline in the same section of primary pipeline, this section of pipeline is regarded as one section of pipeline to be evaluated.

[0030] On the other hand, an embodiment of the present invention provides a computer-readable storage medium comprising a series of instructions for executing the above method steps.

[0031] In addition, an embodiment of the present invention further provides a system for evaluating the failure risk of buried pipelines in geological disaster areas, including: a pipeline segmentation module, which is configured to divide the target pipeline into multiple sections and determine multiple sections of pipelines to be evaluated; a failure possibility calculation module, which is configured to calculate the total probability of leakage risk caused by internal corrosion and geological disaster risks for each section of the pipeline to be evaluated, thereby obtaining the failure possibility of the corresponding pipeline; a risk consequence calculation module, which is configured to determine the severity of the leakage risk consequences of each section of the pipeline to be evaluated; and a risk level generation module, which is configured to determine the risk level of the corresponding pipeline according to the failure possibility and the severity of the leakage risk consequences of each section of the pipeline to be evaluated.

[0032] Compared with the prior art, one or more embodiments of the above scheme may have the following advantages or beneficial effects:

[0033] The present invention proposes a method and system for evaluating the failure risk of buried pipelines in geological disaster areas. The present invention solves the problem that the existing pipeline risk assessment method does not combine the situation that pipeline leakage failure caused by pipeline corrosion and geological disasters. By using the internal corrosion failure probability calculation model, the geological disaster failure probability calculation model and the coupled failure probability calculation model, the failure probability of the pipeline is fully calculated for the dual risks of corrosion and geological disasters, and the risk level of the pipeline is effectively quantitatively assessed in combination with the severity of the consequences of pipeline leakage risks. To this end, the present invention can effectively quantitatively evaluate and grade the "internal corrosion + geological disaster" coupling risk faced by buried natural gas pipelines in geological disaster areas, enhance the pertinence of risk assessment, improve the level of safe operation management and technology of buried pipelines, and help to significantly improve the level of security for the safe and stable operation of buried pipelines in geological disaster areas.

[0034] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 Schematic diagram of the steps of a method for evaluating failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application.

[0037] Figure 2 This is a specific flow chart of a method for evaluating the failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application.

[0038] Figure 3This is an example diagram of the principle of implementing pipeline segmentation in the method for evaluating the failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application.

[0039] Figure 4 Schematic diagram of the overall structure of a system for evaluating failure risks of buried pipelines in disaster-stricken areas according to an embodiment of the present application. DETAILED DESCRIPTION

[0040] The following will describe the implementation methods of the present invention in detail with reference to the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0041] In addition, the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. Also, although a logical sequence is shown in the flowchart, in some cases, the steps shown or described can be performed in a sequence different from that here.

[0042] The terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "one", "one" and "item" used herein are also intended to include plural numbers. It should also be understood that the terms "include" and / or "comprise" used herein specify the existence of stated features, integers, steps, operations, units and / or components, without excluding the existence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0043] In recent years, Sichuan and Chongqing have gradually become one of the main battlefields for oil and gas production in my country. Oil and gas fields are constantly being discovered and developed on a large scale. Since Sichuan and Chongqing are located in mountainous areas and have heavy rainfall, they have also become the hardest hit areas of geological disasters in my country. According to statistics, geological disasters such as landslides and mudslides in Sichuan and Chongqing account for about 14% of the same type of geological disasters in the country. Geological disasters may cause geological changes and ground subsidence, which in turn may cause the joints of natural gas pipelines to loosen and cause natural gas leaks. In addition, the construction of buried pipelines in the geological disaster areas within Sichuan and Chongqing also faces the risk of natural gas leaks caused by widespread corrosion perforation.

[0044] In order to solve the above problems, the present invention proposes a scheme for evaluating the failure risk of buried pipelines in geological disaster areas. The scheme fully considers the dual risks of corrosion and geological disasters that affect buried pipelines, and uses the internal corrosion failure probability calculation model, the geological disaster failure probability calculation model and the coupled failure probability calculation model to fully calculate the failure probability of pipelines for the dual risks of corrosion / geological disasters, and effectively quantifies and evaluates the risk level of pipelines in combination with the severity of the consequences of pipeline leakage risks, thereby enhancing the pertinence of risk assessment and improving the level of safe operation management and technology of buried pipelines.

[0045] Embodiment 1

[0046] Figure 1 Schematic diagram of the steps of a method for evaluating failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application. Figure 2 This is a specific flow chart of the method for evaluating the failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application. Figure 1 and Figure 2 , the specific process of the method for evaluating the failure risk of buried pipelines in disaster-stricken areas disclosed in an embodiment of the present invention is described in detail.

[0047] Step S110: Divide the target pipeline into multiple sections, and determine multiple sections of pipelines to be evaluated.

[0048] First, for the gathering and transportation pipeline network in the disaster area, the target pipeline is divided into multiple sections of primary pipelines with the cut-off valve chamber as the dividing point. Then, the primary pipeline is further divided into multiple sections of pipelines according to different laying types, and the sections laid in the form of crossing and spanning in each section of the pipeline are eliminated, so as to retain the pipelines laid in the form of buried in each section of the primary pipeline, so as to form multiple sections of pipelines to be evaluated.

[0049] In one embodiment, if there are multiple discontinuous pipe sections in the same section of primary pipeline, these discontinuous pipe sections are respectively used as several sections of pipeline to be evaluated for evaluation.

[0050] In one embodiment, if there is only one pipe section in the same section of primary pipeline, then this pipe section is the pipe section to be evaluated.

[0051] Figure 3 This is a schematic diagram of the principle of implementing pipeline segmentation in the method for evaluating the failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application. Figure 3As shown, in step S110, the gathering and transportation pipeline network in the disaster area is first divided into n sections with the cut-off valve chamber of the gathering and transportation pipeline network as the dividing point, and a primary pipeline is formed between every two cut-off valve chambers. If there are tunnel pipelines laid in the form of crossing and truss pipelines laid in the form of spanning in the first section of the primary pipeline, the tunnel pipeline and truss pipeline parts need to be removed, and only three sections of buried pipelines are retained as the 1-1 section of the pipeline to be evaluated, the 1-2 section of the pipeline to be evaluated, and the 1-3 section of the pipeline to be evaluated. If there is only one section of buried pipeline in the second section of the primary pipeline, the entire section is the second section of the evaluation pipeline.

[0052] Step S120: Calculate the total probability of leakage risk caused by internal corrosion risk and geological disaster risk for each section of the pipeline to be evaluated, so as to obtain the failure probability of the corresponding pipeline.

[0053] refer to Figure 2 In step S120, the total probability of internal corrosion leakage risk and the total probability of geological disaster leakage risk are calculated for each section of the pipeline to be evaluated, and the total probability of pipeline leakage risk of the corresponding pipe section is obtained, thereby obtaining the failure possibility of the corresponding section of the pipeline.

[0054] In the embodiment of the present invention, the pipeline to be evaluated is affected by both internal corrosion and geological disasters, so the total probability of internal corrosion leakage risk and the total probability of geological disaster leakage risk need to be calculated separately.

[0055] First, there are three different failure forms of pipeline leakage caused by internal corrosion, which are small hole internal corrosion leakage, medium hole internal corrosion leakage and fracture internal corrosion leakage. Therefore, it is necessary to calculate the leakage risk probability of the above three failure forms through the pipeline internal corrosion leakage risk calculation model, and then obtain the total probability of internal corrosion leakage risk of the pipeline to be evaluated.

[0056] That is to say, in step S120, the small hole internal corrosion leakage risk probability, the medium hole internal corrosion leakage risk probability and the fracture internal corrosion leakage risk probability caused by the internal corrosion of each section of the pipeline to be evaluated are calculated respectively, and based on the leakage risk probabilities of these three failure forms, the total internal corrosion leakage risk probability of each section of the pipeline to be evaluated is obtained.

[0057] The process of calculating the total probability of internal corrosion leakage risk of each section of the pipeline to be evaluated includes: determining the internal detection time correction factor according to the initial effectiveness of the internal detection of the pipeline to be evaluated, the internal detection execution time, the internal detection time increment, and the internal detection validity period, and calculating the effective years of internal corrosion based on the internal detection time correction factor in combination with the pipeline operation years and the internal detection time increment; determining the gathering and transportation medium corrosiveness factor according to the electrical fingerprint corrosion rate of the pipeline to be evaluated; calculating the internal corrosion leakage risk probability of different failure forms in the pipeline to be evaluated based on the effective years of internal corrosion and the gathering and transportation medium corrosiveness factor of the pipeline to be evaluated, in combination with the internal corrosion leakage risk baseline probability, the internal corrosion leakage risk model proportional coefficient, the pipeline wall thickness, the internal corrosion leakage degree correction factor of different failure forms and the pipeline length; and determining the sum of the small hole internal corrosion leakage risk probability, the medium hole internal corrosion leakage risk probability and the fracture internal corrosion leakage risk probability as the total probability of internal corrosion leakage risk of the pipeline to be evaluated.

[0058] Among them, the calculation model of pipeline corrosion leakage risk is as follows:

[0059] R 内腐蚀 =RB 内腐蚀 ×K 内腐蚀 ×(τ 内腐蚀 / t)×FPC×k×L (1)

[0060] Among them, R 内腐蚀 Represents the risk probability of corrosion leakage in the pipeline, dimensionless; RB 内腐蚀 K represents the baseline probability of corrosion leakage risk in the pipeline, dimensionless; 内腐蚀 represents the proportionality coefficient of the internal corrosion leakage risk model, dimensionless; τ 内腐蚀 represents the effective years of corrosion in pipelines; t represents the wall thickness of pipelines, in millimeters; FPC represents the corrosiveness factor of gathering and transportation media, dimensionless; k represents the leakage degree correction factor of different failure modes, dimensionless; L represents the length of pipelines, in kilometers. Among them, the effective years of corrosion in pipelines are expressed by the following expression:

[0061] τ 内腐蚀 =λ×(τ a +Δτ) (2)

[0062]

[0063] Among them, λ represents the internal detection time correction factor, which is dimensionless; β represents the initial effectiveness of the pipeline internal detection, which is dimensionless; τ a represents the operating life of the pipeline; Δτ represents the time increment; τ b Indicates the validity period of the in-pipeline inspection; τ l Indicates the execution time of corrosion detection.

[0064] In one embodiment, in formula (1), the value of the gathering medium corrosivity factor (FPC) is determined by the measured electrical fingerprint corrosion rate (CR). The corresponding relationship between the electrical fingerprint corrosion rate and the gathering medium corrosivity factor is specifically shown in Table 1.

[0065] Table 1 Corresponding relationship between the electric fingerprint corrosion rate and the corrosiveness factor of the gathering and transportation medium

[0066] Electric fingerprint corrosion rate (mm / a) Corrosion factor of gathering and transportation medium CR<0.02 FPC=0.04 0.02≤CR<0.1 FPC=0.2 0.1≤CR<0.5 FPC=1.0 0.5≤CR<2.5 FPC=5.0 2.5≤CR FPC=6.0

[0067] Among them, CR represents the electrical fingerprint corrosion rate (unit: mm / a), which is provided by the measurement data of the oil and gas production enterprises during the electrical fingerprint corrosion rate monitoring process.

[0068] When the pipeline failure forms are small holes, medium holes and fractures, the corresponding leakage correction factors in formula (1) are 0.85, 0.1 and 0.05 respectively.

[0069] The numerical assignment principles for the calculation model of corrosion leakage risk in pipelines are shown in Table 2.

[0070] Table 2 Numerical assignment principles for the calculation model of corrosion leakage risk in pipelines

[0071]

[0072]

[0073] Furthermore, the internal corrosion leakage risk probabilities corresponding to the three different failure modes are calculated according to the following expressions:

[0074] R 内腐蚀小孔泄漏 =RB 内腐蚀 ×K 内腐蚀 ×(τ 内腐蚀 / t)×FPC×0.85×L (4)

[0075] R 内腐蚀中孔泄漏 =RB 内腐蚀 ×K 内腐蚀 ×(τ 内腐蚀 / t)×FPC×0.1×L (5)

[0076] R 内腐蚀断裂泄漏 =RB 内腐蚀 ×K 内腐蚀 ×(τ 内腐蚀 / t)×FPC×0.05×L (6)

[0077] Among them, R 内腐蚀小孔泄漏 Indicates the risk probability of corrosion leakage in the small hole; R 内腐蚀中孔泄漏 Represents the risk probability of corrosion leakage in the hole; R 内腐蚀断裂泄漏Indicates the risk probability of corrosion leakage within the fracture.

[0078] Furthermore, the total probability of internal corrosion leakage risk of each section of pipeline to be evaluated is calculated according to the following expression:

[0079] R 总内腐蚀 =R 内腐蚀小孔泄漏 +R 内腐蚀中孔泄漏 +R 内腐蚀断裂泄漏 (7)

[0080] Among them, R 总内腐蚀 Represents the total probability of internal corrosion leakage risk of the pipeline to be evaluated.

[0081] Secondly, there are three different failure forms of pipeline leakage caused by geological disasters, which are small hole geological disaster leakage, medium hole geological disaster leakage and fracture geological disaster leakage. Therefore, it is necessary to calculate the leakage risk probability of the above three failure forms through the pipeline geological disaster leakage risk calculation model, and then obtain the total probability of geological disaster leakage risk of the pipeline to be evaluated.

[0082] That is to say, step S120 also needs to calculate the small hole geological disaster leakage risk probability, medium hole geological disaster leakage risk probability and fracture geological disaster leakage risk probability caused by geological disasters for each section of the pipeline to be evaluated, and obtain the total geological disaster leakage risk probability of each section of the pipeline to be evaluated based on the geological disaster leakage risk probabilities of these three failure modes.

[0083] The process of calculating the total probability of geological disaster leakage risk of each section of the pipeline to be evaluated includes: determining the corresponding geological disaster warning coefficient according to the geological disaster warning level of the pipeline to be evaluated; determining the pipeline failure frequency according to the pipeline failure level of the pipeline to be evaluated; determining the pipeline connection coefficient according to the pipeline weld quality level of the pipeline to be evaluated; calculating the geological disaster leakage risk probability of different failure forms in the pipeline to be evaluated based on the geological disaster warning coefficient, pipeline failure frequency and pipeline connection coefficient of the pipeline to be evaluated, combined with the geological disaster pipeline failure risk baseline probability, the geological disaster leakage degree correction factor of different failure forms and the pipeline length; and determining the sum of the small hole geological disaster leakage risk probability, the medium hole geological disaster leakage risk probability and the fracture geological disaster leakage risk probability as the total geological disaster leakage risk probability of the pipeline to be evaluated.

[0084] Among them, the pipeline geological disaster leakage risk calculation model is as follows:

[0085] R 地灾 =RB 地灾 ×FYJ×RP 管道失效 ×FJNT×a×L (8)

[0086] Among them, R 地灾 Represents the probability of pipeline geological disaster leakage risk, dimensionless; RB 地灾It represents the baseline probability of pipeline geological disaster leakage risk, which is dimensionless and usually takes a value between 0.01 and 0.001; FYJ represents the geological disaster warning coefficient, which is dimensionless; RP 管道失效 It represents the pipeline failure frequency, which is dimensionless; FJNT represents the pipeline connection coefficient, which is dimensionless; a represents the leakage degree correction factor, which is dimensionless; L represents the pipeline length.

[0087] In formula (8), the value of the geological disaster warning coefficient (FYJ) is determined by the on-site geological disaster warning level. The geological disaster warning levels are attention level, warning level, alert level and alarm level from low to high. In one embodiment, the corresponding relationship between the geological disaster warning level and the geological disaster warning coefficient is specifically shown in Table 3.

[0088] Table 3 Correspondence between geological disaster warning levels and geological disaster warning coefficients

[0089] Geological disaster warning level Geological disaster warning coefficient Disaster warning level = caution level (blue) FYJ=0.5 Geological disaster warning level = warning level (yellow) FYJ=1 Disaster warning level = Warning level (orange) FYJ=1.5 Disaster warning level = Alert level (red) FYJ=2

[0090] Among them, the geological disaster warning coefficient is dynamic data, which is updated in real time according to the geological disaster monitoring system set up by the oil and gas production enterprises and the preset alarm threshold.

[0091] Furthermore, the value of the pipeline failure frequency is determined by the pipeline failure level. The pipeline failure levels are low failure level, medium failure level and high failure level from low to high. In one embodiment, the corresponding relationship between the pipeline failure level and the pipeline failure frequency is specifically shown in Table 4.

[0092] Table 4 Correspondence between pipeline failure level and pipeline failure frequency

[0093]

[0094]

[0095] Furthermore, the value of the pipeline connection coefficient (FJNT) is determined by the quality of the pipeline weld. The pipeline weld quality levels are high-quality weld, medium-quality weld, general-quality weld and mechanical connection from high to low. In one embodiment, the corresponding relationship between the pipeline weld quality and the pipeline connection coefficient is specifically shown in Table 5.

[0096] Table 5 Corresponding relationship between pipeline weld quality and pipeline connection coefficient

[0097] Pipeline weld quality grade Pipe connection coefficient FJNT high quality 0.1 Medium quality 1.0 General quality 4.0 Mechanical connection 8.0

[0098] Among them, the pipeline connection coefficient is static data, which is determined based on the girth weld inspection data after the pipeline is laid. If the pipeline is not re-welded, it will be updated in a timely manner based on the regular girth weld re-inspection results.

[0099] When the pipeline failure forms are small holes, medium holes and fractures, the corresponding leakage correction factors are 0.2, 0.4 and 0.5 respectively. Therefore, the following expressions are used to calculate the risk probability of small hole geological disaster leakage, the risk probability of medium hole geological disaster leakage and the risk probability of fracture geological disaster leakage:

[0100] R 地灾小孔泄漏 =RB 地灾 ×FYJ×RP 管道失效 ×FJNT×0.2×L (9)

[0101] R 地灾中孔泄漏 =RB 地灾 ×FYJ×RP 管道失效 ×FJNT×0.4×L (10)

[0102] R 地灾断裂泄漏 =RB 地灾 ×FYJ×RP 管道失效 ×FJNT×0.5×L (11)

[0103] Among them, R 地灾小孔泄露 R represents the risk probability of small hole geological disaster leakage; 内腐蚀中孔泄漏 R represents the risk probability of medium-hole geological disaster leakage; 内腐蚀断裂泄漏 Indicates the risk probability of leakage from fault geological disasters.

[0104] Furthermore, according to the geological disaster leakage risk probabilities corresponding to the above three different failure modes, the total geological disaster leakage risk probability of each section of the pipeline to be evaluated is calculated using the following expression:

[0105] R 总地灾 =R 地灾小孔泄漏 +R 地灾中孔泄漏 +R 地灾断裂泄漏 (12)

[0106] Among them, R 总地灾 It represents the total probability of geological disaster leakage risk of the pipeline to be evaluated.

[0107] Furthermore, this embodiment fully considers the dual risks of internal corrosion and geological disasters affecting buried pipelines, and uses a coupled failure probability calculation model to calculate the total probability of leakage risk of the target pipeline to enhance the accuracy of the assessment. The coupled failure probability calculation model is as follows:

[0108] R 总泄漏风险 =R 总内腐蚀小孔 +R 总地灾 (13)

[0109] Among them, R 总泄漏风险 Represents the total probability of leakage risk of the target pipeline.

[0110] Further, according to the total probability of pipeline leakage risk, the failure probability level of the pipeline is determined. In an embodiment of the present invention, in order to facilitate risk management, the possibility level range corresponding to the failure probability of pipelines in disaster-stricken areas is specified. In one embodiment, the corresponding relationship between the total probability of pipeline failure in disaster-stricken areas and the possibility level is specifically shown in Table 6.

[0111] Table 6 Correspondence between the total probability of pipeline failure and the probability level in the disaster area

[0112] Total probability of pipeline failure in disaster areas Probability level <![CDATA[Total leakage risk ≤ 10 -6 > 1 <![CDATA[10 -6 <RTotal leakage risk≤10 -5 ]]> 2 <![CDATA[10 -5 <RTotal leakage risk≤10 -4 ]]> 3 <![CDATA[10 -4 <RTotal leakage risk≤10 -3 ]]> 4 <![CDATA[10 -3 <RTotal leakage risk≤10 -2 ]]> 5 <![CDATA[10 -2 <RTotal leakage risk≤10 -1 ]]> 6 <![CDATA[10 -1 <R total leakage risk ≤ 1]]> 7 1<R total leakage risk 8

[0113] Step S130: Determine the severity of the leakage risk consequences of each section of the pipeline to be evaluated.

[0114] Continue to refer Figure 2 In step S130, first, the radius of the potential impact area of ​​the pipeline to be evaluated is determined according to the maximum operating pressure and pipeline specifications of the pipeline to be evaluated. Then, a population survey is conducted on the area within the radius of the current impact area to obtain the casualties. Then, the consequence level is determined based on the casualties to obtain the severity of the leakage risk consequence of the pipeline to be evaluated.

[0115] In one embodiment, the radius of the potential impact area of ​​the current pipeline is calculated using the following expression:

[0116]

[0117] Where r represents the radius of the potential impact area of ​​the pipeline to be evaluated, in m; d represents the outer diameter of the pipeline, in mm; and p represents the maximum allowable operating pressure of the pipeline section to be evaluated, in MPa.

[0118] In actual situations, the corresponding relationship between common pipe diameters, pressures and potential impact radius of natural gas long-distance pipelines is shown in Table 7.

[0119] Table 7 Correspondence between pipe diameter, pressure and potential impact radius

[0120]

[0121]

[0122] In another embodiment, the radius of the potential impact area of ​​the current pipeline is determined according to the pipeline specifications of the pipeline to be evaluated and the maximum operating pressure of the pipeline section. The corresponding relationship between common pipeline specifications, operating pressure and impact radius of long-distance natural gas pipelines is shown in Table 8.

[0123] Table 8 Correspondence between pipeline specifications, operating pressure and impact radius

[0124]

[0125] Furthermore, according to the radius of the pipeline's potential impact area, a population survey is conducted to obtain the casualties of people around the target pipeline section, and then determine the consequence level.

[0126] In one embodiment, the consequence levels are divided into 7 levels according to severity from minor to extremely serious, namely A, B, C, D, E, F and G. The corresponding relationship between the consequence levels and casualties is shown in Table 9.

[0127] Table 9 Correspondence between consequence levels and casualties

[0128]

[0129]

[0130] Step S140: Determine the risk level of each section of the pipeline to be evaluated according to the failure possibility and the severity of the leakage risk consequence of each section of the pipeline to be evaluated.

[0131] In step S140, the risk value is determined according to the failure probability level and the leakage risk consequence severity level of the pipeline to be evaluated. Then, according to the size of the risk value, a risk quantitative assessment is performed on the pipeline to be evaluated, and the risk level is finally determined.

[0132] In one embodiment, the corresponding relationship between the pipeline failure possibility level cascade and the leakage risk consequence level and the final coupled risk value is shown in Table 10.

[0133] Table 10 Correspondence between possibility level, consequence level and risk value

[0134]

[0135] Furthermore, risk levels are divided according to the range of risk values.

[0136] In one embodiment, the risk level is divided into four levels according to severity, from minor to extremely serious, namely low risk, general risk, greater risk and serious risk. The corresponding relationship between the risk level and the risk value is shown in Table 11.

[0137] Table 11 Correspondence between risk level and risk value

[0138]

[0139]

[0140] Embodiment 2

[0141] Based on the above-mentioned first embodiment, a failure risk assessment method for the gathering and transportation pipeline section A in the northeastern Sichuan region is given below.

[0142] S1 pipeline segmentation. It is known that pipe section A is located between valve chamber No. 1 and valve chamber No. 2, the total length of the pipe section is 5km, and there is a truss in the middle of the pipe section. Pipe section A is divided into two sections, A-1 and A-2, with lengths of 2.0km and 1.8km respectively. Now section A-1 is selected for risk assessment.

[0143] S2 calculates the total probability of internal corrosion leakage risk. According to the pipeline design data, corrosion monitoring data, internal inspection data and production and operation conditions, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 12.

[0144] Table 12 Data related to the risk of internal corrosion and leakage in pipeline A-1

[0145]

[0146] The electric fingerprint corrosion rate CR = 0.3 mm / a. According to Table 1, the value of the corrosiveness factor (FPC) of the gathering and transportation medium is 1.0.

[0147] According to formula (2) and formula (3), the effective life of pipeline corrosion is calculated to be 5.37 years.

[0148] Substituting the above data into formula (4), formula (5) and formula (6), we can get the risk probability of corrosion leakage in the small hole as 4.11×10 -5 The risk probability of corrosion leakage in the middle hole is 4.83×10 -6 , the risk probability of corrosion leakage inside the fracture is 2.43×10 -6 According to formula (7), the total probability of corrosion leakage risk in pipeline A-1 is 4.834×10 -5 .

[0149] S3 calculates the total probability of geological disaster leakage risk. Based on the pipeline geological disaster monitoring system data, girth weld assessment results and laying location, the following information is obtained:

[0150] 1) Geological disaster warning level: warning level (orange);

[0151] 2) Pipeline failure level: medium;

[0152] 3) Pipeline weld quality grade: general quality;

[0153] Combined with the corresponding relationship of relevant data in Table 3, Table 4 and Table 5, the relevant data are assigned values ​​comprehensively, as shown in Table 13.

[0154] Table 13 Data related to geological disaster leakage risk of pipeline A-1

[0155]

[0156] Substituting the above data into formula (9), formula (10) and formula (11), we can get the risk probability of small hole geological disaster leakage as 0.0024, the risk probability of medium hole geological disaster leakage as 0.0048, and the risk probability of fracture geological disaster leakage as 0.006. According to formula (12), the total risk probability of A-1 pipeline geological disaster leakage is 0.0132.

[0157] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of leakage risk due to corrosion in the A-1 pipeline is added to the total probability of leakage risk due to geological disasters in the A-1 pipeline, and the total probability of leakage risk due to geological disasters in the A-1 pipeline is calculated to be 1.325×10 -2 According to Table 6, it can be determined that the failure probability level of the A-1 pipeline is level 6.

[0158] S5 determines the consequence level of pipeline failure leakage. According to the specification of the A-1 pipe section, which is Φ219.110 and the operating pressure is 8.6MPa, combined with Table 8, it can be obtained that the impact radius after leakage is 292m. According to the population survey data, with the A-1 pipe section as the axis, the permanent population within 292 meters around the pipeline is 6 people. Pipeline leakage and fire explosion will cause at least 2 deaths and 4 serious injuries. Combined with Table 9, it can be determined that the consequence level of pipeline failure leakage is D.

[0159] S6 Risk Quantification Evaluation and Classification. According to Table 10, when the possibility level of A-1 pipeline leakage is level 6 and the consequence level is level D, the corresponding risk value is 37. Based on the corresponding relationship between risk level and risk value given in Table 11, it can be determined that the risk level is orange, which indicates a high risk.

[0160] Embodiment 3

[0161] Based on the above-mentioned first embodiment, a failure risk assessment method for the gathering and transportation pipeline section B in the northeastern Sichuan region is given below.

[0162] S1 pipeline segmentation. It is known that the B pipe section is located between valve chambers 5 and 6, with a total length of 4.3 km. There is a truss and a tunnel in the middle of the pipe section. The B pipe section is divided into three sections: B-1, B-2 and B-3, with lengths of 1.0 km, 0.6 km and 1.8 km respectively. The B-1 section is now selected for risk assessment.

[0163] S2 calculates the total probability of internal corrosion leakage risk. According to the pipeline design data, corrosion monitoring data, internal inspection data and production and operation conditions, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 14.

[0164] Table 14 Data related to internal corrosion leakage risk of pipeline B-1

[0165] Serial number parameter Representative symbol unit Value 1 Internal corrosion benchmark failure frequency <![CDATA[RB 内腐蚀 ]]> times / km·year 0.0004 2 Internal corrosion model scale factor <![CDATA[K 内腐蚀 ]]> / 0.18 3 Initial validity of internal testing β ％ 95 4 Internal detection execution time <![CDATA[τ l ]]> Year 0.4(146 days ago) 5 Time increment Δτ Year 0.8 6 Internal test validity period <![CDATA[τ b ]]> Year 2 7 Pipeline operation life <![CDATA[τ a ]]> Year 7 8 Pipe diameter / wall thickness t mm Φ273*12.5 9 Electric fingerprint corrosion rate / mm / a 1.0 10 Pipe length L Km 1

[0166] The electric fingerprint corrosion rate CR = 1.0 mm / a, and the value of the corrosiveness factor (FPC) of the gathering and transportation medium is 5.0 according to Table 1.

[0167] According to formula (2) and formula (3), the effective life of pipeline corrosion is calculated to be 3.06 years.

[0168] Substituting the above data into formula (4), formula (5) and formula (6), we can get the risk probability of corrosion leakage in the small hole as 1.5×10 -5 The risk probability of corrosion leakage in the middle hole is 1.76×10 -6 , the risk probability of corrosion leakage inside the fracture is 8.81×10 -6 According to formula (7), the total probability of corrosion leakage risk in pipeline B-1 is 1.76×10 -5 .

[0169] S3 calculates the total probability of geological disaster leakage risk. Based on the pipeline geological disaster monitoring system data, girth weld assessment results and laying location, the following information is obtained:

[0170] 1) Geological disaster warning level: caution level (blue);

[0171] 2) Pipeline failure level: low;

[0172] 3) Pipeline weld quality grade: medium quality;

[0173] Based on the corresponding relationship between the relevant data in Table 3, Table 4 and Table 5, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 15.

[0174] Table 15 Data related to geological disaster leakage risk of pipeline B-1

[0175]

[0176] Substituting the above data into formula (9), formula (10) and formula (11), we can get the risk probability of small hole geological disaster leakage as 5×10 -6 The risk probability of leakage from a medium-sized hole is 1×10 -5 The probability of leakage from fault disasters is 1.25×10 -5 According to formula (12), the total probability of B-1 pipeline geological disaster leakage risk is calculated to be 2.75×10 -5 .

[0177] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of leakage risk due to corrosion in the B-1 pipeline is added to the total probability of leakage risk due to geological disasters in the B-1 pipeline, and the total probability of leakage risk due to geological disasters in the B-1 pipeline is calculated to be 4.5×10 -5According to Table 6, it can be determined that the failure probability level of the B-1 pipeline is level 3.

[0178] S5 determines the consequence level of pipeline failure leakage. According to the specifications of the B-1 pipe section, which is Φ273*12.5 and the operating pressure is 8.5MPa, combined with Table 8, it can be obtained that the impact radius after leakage is 380m. According to the population survey data, with the B-1 pipe section as the axis, the permanent population within 380 meters around the pipeline is 2 people. Pipeline leakage and fire explosion will cause at least 2 people to be slightly injured. Combined with Table 9, it can be determined that the consequence level of pipeline failure leakage is Class B.

[0179] S6 Risk quantification and classification. According to Table 10, when the possibility level of B-1 pipeline leakage is level 3 and the consequence level is level B, the corresponding risk value is 3. Based on the corresponding relationship between risk level and risk value given in Table 11, it can be determined that the risk level is blue low risk.

[0180] Embodiment 4

[0181] Based on the above-mentioned first embodiment, a failure risk assessment method for the gathering and transportation pipeline section C in the northeastern Sichuan region is given below.

[0182] S1 pipeline segmentation. It is known that the C pipe section is located between valve chamber No. 6 and valve chamber No. 7, the total length of the pipe section is 9km, there is a truss and 2 tunnels in the middle of the pipe section, and the C pipe section is divided into four sections: C-1, C-2, C-3 and C-4, with lengths of 1.0km, 0.6km, 4.5km and 1.8km respectively. The C-3 section is now selected for risk assessment.

[0183] S2 calculates the total probability of internal corrosion leakage risk. According to the pipeline design data, corrosion monitoring data, internal inspection data and production and operation conditions, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 16.

[0184] Table 16 Data related to the risk of internal corrosion and leakage in pipeline C-3

[0185]

[0186]

[0187] The electric fingerprint corrosion rate CR = 0.6 mm / a. According to Table 1, the value of the corrosiveness factor (FPC) of the gathering and transportation medium is 5.0.

[0188] According to formula (2) and formula (3), the effective life of pipeline corrosion is calculated to be 6.03 years.

[0189] Substituting the above data into formula (4), formula (5) and formula (6), we can get the risk probability of corrosion leakage in the small hole as 6.59×10-4 The risk probability of corrosion leakage in the middle hole is 7.75×10 -5 , the risk probability of corrosion leakage inside the fracture is 3.88×10 -5 According to formula (7), the total probability of corrosion leakage risk in C-3 pipeline is 7.75×10 -4 .

[0190] S3 calculates the total probability of geological disaster leakage risk. Based on the pipeline geological disaster monitoring system data, girth weld assessment results and laying location, the following information is obtained:

[0191] 1) Geological disaster warning level: Alert level (red);

[0192] 2) Pipeline failure level: high;

[0193] 3) Pipeline weld quality grade: general quality;

[0194] Combined with the corresponding relationship of relevant data in Table 3, Table 4 and Table 5, the relevant data are assigned values ​​comprehensively, as shown in Table 17.

[0195] Table 17 Data related to geological disaster leakage risk of pipeline C-3

[0196]

[0197] Substituting the above data into formula (9), formula (10) and formula (11), we can get the risk probability of small hole geological disaster leakage as 0.0576, the risk probability of medium hole geological disaster leakage as 0.1152, and the risk probability of fracture geological disaster leakage as 0.144. According to formula (12), the total risk probability of geological disaster leakage of C-3 pipeline is calculated to be 0.3168.

[0198] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of corrosion leakage risk in the C-3 pipeline is added to the total probability of geological disaster leakage risk in the C-3 pipeline, and the total probability of leakage risk of the C-3 pipeline is calculated to be 0.3176. According to Table 6, the failure probability level of the C-3 pipeline can be determined to be level 7.

[0199] S5 determines the consequence level of pipeline failure and leakage. According to the specifications of the C-3 pipe section, which is Φ457*28 and the operating pressure is 9.3MPa, combined with Table 8, it can be obtained that the impact radius after leakage is 1050m. According to the population survey data, with the C-3 pipe section as the axis, the permanent population within 1050 meters around the pipeline is 10 people. Pipeline leakage and fire explosion will cause at least 3 deaths. Combined with Table 9, it can be determined that the consequence level of pipeline failure and leakage is E.

[0200] S6 Risk quantification and classification. According to Table 10, when the probability level of C-3 pipeline leakage is 7 and the consequence level is E, the corresponding risk value is 68. Based on the corresponding relationship between risk level and risk value given in Table 11, it can be determined that the risk level is red major risk.

[0201] Embodiment 5

[0202] Based on the above-mentioned first embodiment, a failure risk assessment method for the gathering and transportation pipeline section D in the northeastern Sichuan region is given below.

[0203] S1 pipeline segmentation. It is known that the D pipeline segment is located between valve chambers 6 and 7, with a total length of 2 km. There is a tunnel in the middle of the pipeline segment. The D pipeline segment is divided into two sections, D-1 and D-2, with lengths of 0.5 km and 0.8 km respectively. The D-2 section is now selected for risk assessment.

[0204] S2 calculates the total probability of internal corrosion leakage risk. According to the pipeline design data, corrosion monitoring data, internal inspection data and production and operation conditions, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 18.

[0205] Table 18 Data related to the risk of internal corrosion and leakage in pipeline D-2

[0206] Serial number parameter Representative symbol unit Value 1 Internal corrosion benchmark failure frequency <![CDATA[RB 内腐蚀 ]]> times / km·year 0.0005 2 Internal corrosion model scale factor <![CDATA[K 内腐蚀 ]]> / 0.3 3 Initial validity of internal testing β ％ 90 4 Internal detection execution time <![CDATA[τ l ]]> Year 0.7(256 days ago) 5 Time increment Δτ Year 1.0 6 Internal test validity period <![CDATA[τ b ]]> Year 3 7 Pipeline operation life <![CDATA[τ a ]]> Year 7 8 Pipe diameter / wall thickness t mm Φ168.3*8.8 9 Electrical fingerprint corrosion rate / mm / a 0.25 10 Pipe length L Km 0.8

[0207] The electric fingerprint corrosion rate CR = 1.0 mm / a. According to Table 1, the value of the corrosiveness factor (FPC) of the gathering and transportation medium is 1.0.

[0208] According to formula (2) and formula (3), the effective life of pipeline corrosion is calculated to be 3.112 years.

[0209] Substituting the above data into formula (4), formula (5) and formula (6), we can get the risk probability of corrosion leakage in the small hole as 3.6×10 -5 The risk probability of corrosion leakage in the middle hole is 4.24×10 -6 , the risk probability of corrosion leakage inside the fracture is 2.12×10 -6 According to formula (7), the total probability of corrosion leakage risk in the D-2 pipeline is 4.24×10 -5 .

[0210] S3 calculates the total probability of geological disaster leakage risk. Based on the pipeline geological disaster monitoring system data, girth weld assessment results and laying location, the following information is obtained:

[0211] 1) Geological disaster warning level: warning level (yellow);

[0212] 2) Pipeline failure level: medium;

[0213] 3) Pipeline weld quality grade: high quality;

[0214] Combined with the corresponding relationship of relevant data in Table 3, Table 4 and Table 5, the relevant data are assigned values ​​comprehensively, as shown in Table 19.

[0215] Table 19 Data related to geological disaster leakage risk of pipeline D-2

[0216]

[0217] Substituting the above data into formula (9), formula (10) and formula (11), we can get the risk probability of small hole geological disaster leakage as 8×10 -6 The risk probability of leakage from a medium-sized hole is 1.6×10 -5 The probability of leakage from fault disasters is 2×10 -5 According to formula (12), the total probability of leakage risk of D-2 pipeline is 4.4×10 -5 .

[0218] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of leakage risk due to corrosion in the D-2 pipeline is added to the total probability of leakage risk due to geological disasters in the D-2 pipeline, and the total probability of leakage risk due to geological disasters in the D-2 pipeline is calculated to be 8.64×10 -5 According to Table 6, it can be determined that the failure probability level of the D-2 pipeline is level 3.

[0219] S5 determines the consequence level of pipeline failure leakage. According to the specifications of the D-2 pipe section, which is Φ168.3*8.8 and the operating pressure is 8.8MPa, combined with Table 8, it can be obtained that the impact radius after leakage is 230m. According to the population survey data, with the D-2 pipe section as the axis, the permanent population within 230 meters around the pipeline is 20 people. Pipeline leakage and fire explosion will cause at least 4 deaths and 10 serious injuries. Combined with Table 9, it can be determined that the consequence level of pipeline failure leakage is E.

[0220] S6 Risk quantification and classification. According to Table 10, when the D-2 pipeline leakage possibility level is level 3 and the consequence level is level E, the corresponding risk value is 15. Based on the corresponding relationship between risk level and risk value given in Table 11, it can be determined that the risk level is yellow general risk.

[0221] Embodiment 6

[0222] Based on the above-mentioned first embodiment, a failure risk assessment method for the gathering and transportation pipeline section a in the western Sichuan region is given below.

[0223] S1 pipeline segmentation. It is known that the a pipe segment is located between the a1 valve chamber and the a2 valve chamber, the total length of the pipe segment is 3.9 km, there is a truss and a tunnel in the middle of the pipe segment, the a pipe segment is divided into three sections: a-1, a-2, and a-3, with lengths of 1.0 km, 0.6 km, and 1.8 km respectively. Now the a-3 section is selected for risk assessment.

[0224] S2 calculates the total probability of internal corrosion leakage risk. According to the pipeline design data, corrosion monitoring data, internal inspection data and production and operation conditions, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 20.

[0225] Table 20 Data related to the risk of internal corrosion and leakage in pipeline a-3

[0226] Serial number parameter Representative symbol unit Value 1 Internal corrosion benchmark failure frequency <![CDATA[RB 内腐蚀 ]]> times / km·year 0.002 2 Internal corrosion model scale factor <![CDATA[K 内腐蚀 ]]> / 0.5 3 Initial validity of internal testing β ％ 80 4 Internal detection execution time <![CDATA[τ l ]]> Year 0.2(73 days ago) 5 Time increment Δτ Year 1.0 6 Internal test validity period <![CDATA[τ b ]]> Year 2 7 Pipeline operation life <![CDATA[τ a ]]> Year 10 8 Pipe diameter / wall thickness t mm Φ406.4*17.5 9 Electric fingerprint corrosion rate / mm / a 1.2 10 Pipe length L Km 1.8

[0227] The electric fingerprint corrosion rate CR = 1.2 mm / a. According to Table 1, the value of the corrosiveness factor (FPC) of the gathering and transportation medium is 5.0.

[0228] According to formula (2) and formula (3), the effective life of pipeline corrosion is calculated to be 5.368 years.

[0229] Substituting the above data into formula (4), formula (5) and formula (6), we can get the risk probability of corrosion leakage in the small hole as 46.93×10 -5 , the risk probability of corrosion leakage in the middle hole is 55.21×10 -6 , the risk probability of corrosion leakage inside the fracture is 27.61×10 -6 According to formula (7), the total probability of corrosion leakage risk in pipeline a-3 is 55.214×10 -5 .

[0230] S3 calculates the total probability of geological disaster leakage risk. Based on the pipeline geological disaster monitoring system data, girth weld assessment results and laying location, the following information is obtained:

[0231] 1) Geological disaster warning level: warning level (yellow);

[0232] 2) Pipeline failure level: medium;

[0233] 3) Pipeline weld quality grade: medium quality;

[0234] Combined with the corresponding relationship between the relevant data in Table 3, Table 4 and Table 5, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 20.

[0235] Table 21 Data related to the risk of geological disaster leakage in pipeline a-3

[0236]

[0237] Substituting the above data into formula (9), formula (10) and formula (11), we can get the risk probability of small hole geological disaster leakage as 21.6×10 -5 The risk probability of leakage from a medium-sized hole is 43.2×10 -5 The probability of leakage from fault disasters is 54×10 -5 According to formula (12), the total probability of leakage risk of a-3 pipeline is 118.8×10 -5 .

[0238] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of leakage risk due to corrosion in the a-3 pipeline is added to the total probability of leakage risk due to geological disasters in the a-3 pipeline, and the total probability of leakage risk due to geological disasters in the a-3 pipeline is calculated to be 1.28×10 -3 According to Table 6, it can be determined that the failure probability level of the a-3 pipeline is level 5.

[0239] S5 determines the consequence level of pipeline failure and leakage. According to the specifications of the a-3 pipe section, which is Φ406.4*17.5 and the operating pressure is 8.4MPa, combined with Table 8, it can be obtained that the impact radius after leakage is 800m. According to the population survey data, with the a-3 pipe section as the axis, the permanent population within 800 meters around the pipeline is 5 people. Pipeline leakage and fire explosion will at least cause 1 death and 3 serious injuries. Combined with Table 9, it can be determined that the consequence level of pipeline failure and leakage is D.

[0240] S6 Risk Quantification Evaluation and Classification. According to Table 10, when the possibility level of a-3 pipeline leakage is 5 and the consequence level is D, the corresponding risk value is 25. Based on the corresponding relationship between risk level and risk value given in Table 11, it can be determined that the risk level is orange, which is a high risk.

[0241] Embodiment 7

[0242] Based on the above-mentioned embodiment 1, a failure risk assessment method for the gathering and transportation pipeline section b in the western Sichuan region is given below.

[0243] S1 pipeline segmentation. It is known that the b pipeline segment is located between the b3 valve chamber and the b4 valve chamber, the total length of the pipeline segment is 2.3 km, and there are no trusses and tunnels in the pipeline segment. Now, a risk assessment is conducted on the b pipeline segment.

[0244] S2 calculates the total probability of internal corrosion leakage risk. According to the pipeline design data, corrosion monitoring data, internal inspection data and production and operation conditions, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 22.

[0245] Table 22 Data related to corrosion and leakage risk in pipeline b

[0246] Serial number parameter Representative symbol unit Value 1 Internal corrosion benchmark failure frequency <![CDATA[RB 内腐蚀 ]]> times / km·year 0.008 2 Internal corrosion model scale factor <![CDATA[K 内腐蚀 ]]> / 0.45 3 Initial validity of internal testing β ％ 95 4 Internal detection execution time <![CDATA[τ l ]]> Year 0.6(219 days ago) 5 Time increment Δτ Year 1.0 6 Internal test validity period <![CDATA[τ b ]]> Year 2 7 Pipeline operation life <![CDATA[τ a ]]> Year 2 8 Pipe diameter / wall thickness t mm Φ323.9*14.2 9 Electrical fingerprint corrosion rate / mm / a 0.09 10 Pipe length L Km 2.3

[0247] The electric fingerprint corrosion rate CR = 0.4 mm / a. According to Table 1, the value of the corrosiveness factor (FPC) of the gathering and transportation medium is 1.0.

[0248] According to formula (2) and formula (3), the effective life of pipeline corrosion is calculated to be 1.97 years.

[0249] Substituting the above data into formula (4), formula (5) and formula (6), we can obtain the risk probability of corrosion leakage in small holes as 0.0009784, the risk probability of corrosion leakage in medium holes as 0.0001151, and the risk probability of corrosion leakage in fractures as 57.55×10 -6 According to formula (7), the total probability of corrosion leakage risk in pipeline b is 0.001151.

[0250] S3 calculates the total probability of geological disaster leakage risk. Based on the pipeline geological disaster monitoring system data, girth weld assessment results and laying location, the following information is obtained:

[0251] 1) Geological disaster warning level: warning level (orange);

[0252] 2) Pipeline failure level: medium;

[0253] 3) Pipeline weld quality grade: general quality;

[0254] Based on the corresponding relationship between the relevant data in Table 3, Table 4 and Table 5, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 22.

[0255] Table 23 Data related to geological disaster leakage risk of pipeline b

[0256]

[0257] Substituting the above data into formula (9), formula (10) and formula (11), we can get the risk probability of small hole geological disaster leakage as 0.000828, the risk probability of medium hole geological disaster leakage as 0.001656, and the risk probability of fracture geological disaster leakage as 0.00207. According to formula (12), the total risk probability of geological disaster leakage of pipeline b is calculated to be 0.004554.

[0258] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of leakage risk of pipeline b due to corrosion is added to the total probability of leakage risk of pipeline b due to geological disasters, and the total probability of leakage risk of pipeline b is calculated to be 6.105×10 -3 According to Table 6, it can be determined that the failure probability level of pipeline b is level 5.

[0259] S5 determines the consequence level of pipeline failure leakage. According to the specifications of the pipe in section b, which is Φ323.9*14.2 and the operating pressure is 8.4MPa, combined with Table 8, it can be obtained that the impact radius after leakage is 450m. According to the population survey data, with section b as the axis, the permanent population within 450 meters around the pipeline is 3 people. Pipeline leakage and fire explosion will cause at least 1 person to be seriously injured and 3 people to be slightly injured. Combined with Table 9, it can be determined that the consequence level of pipeline failure leakage is C.

[0260] S6 Risk quantification and classification. According to Table 10, when the probability level of pipeline b leakage is 5 and the consequence level is C, the corresponding risk value is 11. Based on the corresponding relationship between risk level and risk value given in Table 11, it can be determined that the risk level is yellow general risk.

[0261] Embodiment 8

[0262] Based on the above-mentioned first embodiment, a failure risk assessment method for the gathering and transportation pipeline section I in North China is given below.

[0263] S1 pipeline segmentation. It is known that the Ⅰ section is located between the H2 valve room and the H3 valve room, the total length of the section is 7.7km, there is a truss and a tunnel in the middle of the section, the Ⅰ section is divided into Ⅰ-1, Ⅰ-2 and Ⅰ-3, the lengths are 2.0km, 2.5 and 1.8km respectively, and the Ⅰ-1 section is selected for risk assessment.

[0264] S2 calculates the total probability of internal corrosion leakage risk. According to the pipeline design data, corrosion monitoring data, internal inspection data and production and operation conditions, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 24.

[0265] Table 24 Data related to the risk of internal corrosion and leakage in pipeline Ⅰ-1

[0266]

[0267]

[0268] The electric fingerprint corrosion rate CR = 0.15 mm / a. According to Table 1, the value of the corrosiveness factor (FPC) of the gathering and transportation medium is 1.0.

[0269] According to formula (2) and formula (3), the effective life of pipeline corrosion is calculated to be 3.12 years.

[0270] Substituting the above data into formula (4), formula (5) and formula (6), we can get the risk probability of corrosion leakage in the small hole as 5.974×10 -5 The risk probability of corrosion leakage in the middle hole is 7.03×10 -6, the risk probability of corrosion leakage inside the fracture is 3.51×10 -6 According to formula (7), the total probability of corrosion leakage risk in pipeline Ⅰ-1 is 7.028×10 -5 .

[0271] S3 calculates the total probability of geological disaster leakage risk. Based on the pipeline geological disaster monitoring system data, girth weld assessment results and laying location, the following information is obtained:

[0272] 1) Geological disaster warning level: Alert level (red);

[0273] 2) Pipeline failure level: high;

[0274] 3) Pipeline weld quality grade: high quality;

[0275] Based on the corresponding relationship between the relevant data in Table 3, Table 4 and Table 5, the relevant data are assigned values ​​in a comprehensive manner, as shown in Table 25.

[0276] Table 25 Data related to geological disaster leakage risk of pipeline Ⅰ-1

[0277]

[0278] Substituting the above data into formula (9), formula (10) and formula (11), we can get the risk probability of small hole geological disaster leakage as 0.0008, the risk probability of medium hole geological disaster leakage as 0.0016, and the risk probability of fracture geological disaster leakage as 0.002. According to formula (12), the total risk probability of geological disaster leakage of pipeline Ⅰ-1 is calculated to be 0.0044.

[0279] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of pipeline leakage due to corrosion in Ⅰ-1 pipeline is added to the total probability of pipeline leakage due to geological disasters in Ⅰ-1 pipeline, and the total probability of pipeline leakage due to geological disasters in Ⅰ-1 pipeline is calculated to be 4.47×10 -3 According to Table 6, it can be determined that the failure probability level of the Ⅰ-1 pipeline is level 5.

[0280] S5 determines the consequence level of pipeline failure and leakage. According to the specifications of the pipeline in section Ⅰ-1, which is Φ508*22.2 and the operating pressure is 9.1MPa, combined with Table 8, it can be obtained that the impact radius after leakage is 1350m. According to the population survey data, with section Ⅰ-1 as the axis, the permanent population within 1350 meters around the pipeline is 50 people. Pipeline leakage and fire explosion will cause at least 15 deaths and 20 serious injuries. Combined with Table 9, it can be determined that the consequence level of pipeline failure and leakage is F.

[0281] S6 Risk quantification and classification. According to Table 10, when the probability level of pipeline leakage in I-1 is 5 and the consequence level is F, the corresponding risk value is 43. Based on the corresponding relationship between risk level and risk value given in Table 11, it can be determined that the risk level is a red major risk.

[0282] Embodiment 9

[0283] Based on the above-mentioned method for evaluating the failure risk of buried pipelines in disaster-stricken areas in Embodiments 1 to 8, the present invention also provides a computer-readable storage medium, on which a computer program is stored, and the computer program is executed to run a method for evaluating the failure risk of buried pipelines in disaster-stricken areas. The computer program can run computer instructions, and the computer instructions include computer program code, which can be in source code form, object code form, executable file or some intermediate form, etc.

[0284] Computer-readable storage media may include: any entity or device that can carry computer program code, recording media, USB flash drives, mobile hard disks, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0285] It should be noted that the content contained in computer-readable storage media can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, the content contained in computer-readable storage media does not include electrical carrier signals and telecommunication signals.

[0286] Embodiment 10

[0287] Based on the method for evaluating the failure risk of buried pipelines in disaster-stricken areas described in the first to eighth embodiments, the present invention also provides a system for evaluating the failure risk of buried pipelines in disaster-stricken areas. The system is used to implement the method for evaluating the failure risk of buried pipelines in disaster-stricken areas described in the first to eighth embodiments.

[0288] Figure 4 Schematic diagram of the overall structure of the system for evaluating the failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application. Figure 4 As shown, the system described in the embodiment of the present invention includes: a pipeline segmentation module 401, a failure possibility calculation module 402, a risk consequence calculation module 403 and a risk degree generation module 404.

[0289] Specifically, the pipeline segmentation module 401 is implemented according to the method described in the above step S110, and is configured to divide the target pipeline into multiple sections to determine multiple sections of pipelines to be evaluated; the failure possibility calculation module 402 is implemented according to the method described in the above step S120, and is configured to calculate the total probability of leakage risk caused by internal corrosion and geological disaster risks for each section of the pipeline to be evaluated, thereby obtaining the failure possibility of the corresponding pipeline; the risk consequence calculation module 403 is implemented according to the method described in the above step S130, and is configured to determine the severity of the leakage risk consequences of each section of the pipeline to be evaluated; the risk level generation module 404 is implemented according to the method described in the above step S140, and is configured to determine the risk level of the corresponding pipeline according to the failure possibility and the severity of the leakage risk consequences of each section of the pipeline to be evaluated.

[0290] The present invention discloses a method and system for evaluating the failure risk of buried pipelines in geological disaster areas. The method and system solve the problem that the existing pipeline risk assessment method does not combine the situation that pipeline leakage failures caused by pipeline corrosion and geological disasters. By using the internal corrosion failure probability calculation model, the geological disaster failure probability calculation model and the coupled failure probability calculation model, the failure probability of the pipeline is fully calculated for the dual risks of corrosion and geological disasters, and the risk level of the pipeline is effectively quantitatively assessed in combination with the severity of the consequences of pipeline leakage risks. To this end, the present invention can effectively quantitatively evaluate and grade the "internal corrosion + geological disaster" coupling risks faced by buried natural gas pipelines in geological disaster areas, enhance the pertinence of risk assessment, improve the level of safe operation management and technology of buried pipelines, and help to significantly improve the level of security for the safe and stable operation of buried pipelines in geological disaster areas.

[0291] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any person familiar with the technology within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0292] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0293] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0294] It should be understood that the embodiments disclosed in the present invention are not limited to the specific structures, processing steps or materials disclosed herein, but should be extended to equivalent substitutions of these features understood by ordinary technicians in the relevant field. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not meant to be limiting.

[0295] The "one embodiment" or "embodiment" mentioned in the specification means that the specific features, structures or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment" or "embodiment" appearing in various places throughout the specification do not necessarily refer to the same embodiment.

[0296] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for evaluating the failure risk of buried pipelines in disaster-stricken areas, characterized in that: include: Step 1: Divide the target pipeline into multiple sections and determine multiple sections of pipelines to be evaluated; Step 2: Calculate the total probability of leakage risk caused by internal corrosion and geological disaster risks for each section of the pipeline to be evaluated, so as to obtain the failure probability of the corresponding pipeline; Step 3: Determine the severity of the consequences of leakage risk for each section of pipeline to be evaluated; Step 4: Determine the risk level of the corresponding pipeline based on the failure possibility and the severity of the leakage risk consequences of each section of the pipeline to be evaluated.

2. The method according to claim 1, characterized in that The step 2 includes: The risk probability of small hole internal corrosion leakage, medium hole internal corrosion leakage and fracture internal corrosion leakage caused by internal corrosion of each section of the pipeline to be evaluated are calculated respectively, and based on this, the total probability of internal corrosion leakage risk of each section of the pipeline to be evaluated is obtained; The risk probability of small-hole geological disaster leakage, medium-hole geological disaster leakage and fracture geological disaster leakage caused by geological disasters in each section of the pipeline to be evaluated are calculated respectively, and based on this, the total probability of geological disaster leakage risk of each section of the pipeline to be evaluated is obtained; According to the total probability of internal corrosion leakage risk and the total probability of geological disaster leakage risk of each section of pipeline to be evaluated, the total probability of pipeline leakage risk of the corresponding section is obtained, thereby obtaining the failure possibility of the corresponding section of pipeline.

3. The method according to claim 2, characterized in that The process of calculating the total probability of internal corrosion leakage risk for each section of pipeline to be evaluated includes: Determine the internal inspection time correction factor according to the initial effectiveness of the internal inspection of the pipeline to be evaluated, the internal inspection execution time, the internal inspection time increment, and the internal inspection validity period, and calculate the effective years of internal corrosion according to the internal inspection time correction factor, combined with the pipeline operation years and the internal inspection time increment; Determine the corrosiveness factor of the gathering and transportation medium according to the electrical fingerprint corrosion rate of the pipeline to be evaluated; According to the effective years of internal corrosion of the pipeline to be evaluated and the corrosiveness factor of the gathering and transportation medium, combined with the internal corrosion leakage risk baseline probability, the internal corrosion leakage risk model proportionality coefficient, the pipeline wall thickness, the internal corrosion leakage degree correction factor of different failure forms and the pipeline length, the internal corrosion leakage risk probability of different failure forms in the pipeline to be evaluated is calculated; The sum of the small hole internal corrosion leakage risk probability, the medium hole internal corrosion leakage risk probability and the fracture internal corrosion leakage risk probability is determined as the total internal corrosion leakage risk probability of the pipeline to be evaluated.

4. The method according to claim 3, characterized in that The risk probability of internal corrosion leakage in different failure modes is expressed by the following expression: R 内腐蚀 =RB 内腐蚀 ×K 内腐蚀 ×(t 内腐蚀 / t)×FPC×k×L Among them, R 内腐蚀 Represents the risk probability of corrosion leakage in the pipeline, RB 内腐蚀 represents the baseline probability of corrosion leakage risk in the pipeline, K 内腐蚀 represents the proportional coefficient of the internal corrosion leakage risk model; τ 内腐蚀 represents the effective life of pipeline internal corrosion, t represents the pipeline wall thickness, FPC represents the corrosiveness factor of the gathering and transportation medium, k represents the leakage degree correction factor of different failure forms, and L represents the pipeline length, wherein the effective life of internal corrosion is expressed by the following expression: t 内腐蚀 =λ×(τ a +Δt) Among them, λ represents the internal detection time correction factor, β represents the initial effectiveness of the pipeline internal detection, and τ a represents the operating life of the pipeline, Δτ represents the time increment, τ b represents the validity period of the in-pipeline detection, τ l Indicates the execution time of corrosion detection.

5. The method according to claim 3 or 4, characterized in that: The correction factors for internal corrosion leakage of small holes, medium holes and fractures are 0.85, 0.1 and 0.05 respectively; and The corresponding relationship between the electrical fingerprint corrosion rate and the corrosiveness factor of the gathering and transportation medium is: When the electrical fingerprint corrosion rate is less than 0.02, the corrosivity factor of the gathering and transportation medium is 0.04; When the electrical fingerprint corrosion rate is greater than or equal to 0.02 and less than 0.1, the corrosiveness factor of the gathering and transportation medium is 0.2; When the electrical fingerprint corrosion rate is greater than or equal to 0.1 and less than 0.5, the corrosivity factor of the gathering and transportation medium is 1.0; When the electrical fingerprint corrosion rate is greater than or equal to 0.5 and less than 2.5, the corrosivity factor of the gathering and transportation medium is 5.0; When the electrical fingerprint corrosion rate is greater than or equal to 2.5, the corrosivity factor of the gathering and transportation medium is 6.

0.

6. The method according to any one of claims 2 to 5, characterized in that: The process of calculating the total probability of geological disaster leakage risk for each section of pipeline to be evaluated includes: Determine the corresponding geological disaster warning coefficient according to the geological disaster warning level of the pipeline to be evaluated; Determine the pipeline failure frequency according to the pipeline failure level of the pipeline to be evaluated; Determine the pipeline connection coefficient according to the pipeline weld quality grade of the pipeline to be evaluated; According to the geological disaster warning coefficient, pipeline failure frequency and pipeline connection coefficient of the pipeline to be evaluated, combined with the baseline probability of geological disaster pipeline failure risk, the correction factor of geological disaster leakage degree of different failure forms and pipeline length, the geological disaster leakage risk probability of different failure forms in the pipeline to be evaluated is calculated; The sum of the small-hole geological disaster leakage risk probability, the medium-hole geological disaster leakage risk probability and the fracture geological disaster leakage risk probability is determined as the total geological disaster leakage risk probability of the pipeline to be evaluated.

7. The method according to claim 6, characterized in that The risk probability of geological disaster leakage in different failure modes is expressed by the following expression: R 地灾 =RB 地灾 ×FYJ×RP 管道失效 ×FJNT×a×L Among them, R 地灾 represents the probability of pipeline geological disaster leakage risk, RB 地灾 represents the baseline probability of pipeline geological disaster leakage risk, FYJ represents the geological disaster warning coefficient, RP 管道失效 represents the pipeline failure frequency, FJNT represents the pipeline connection coefficient, a represents the leakage degree correction factor, and L represents the pipeline length.

8. The method according to claim 6 or 7, characterized in that: The correction factors for the degree of geological disaster leakage of small holes, medium holes and faults are 0.2, 0.4 and 0.5 respectively; When the geological disaster warning levels are from low to high, namely, attention level, warning level, alert level and alarm level, the corresponding geological disaster warning coefficients are 0.5, 1, 1.5 and 2 respectively; When the pipeline failure levels are low failure level, medium failure level and high failure level from low to high, the corresponding pipeline failure frequencies are 0.01, 0.1 and 1 respectively; When the quality grades of pipeline welds are high-quality welds, medium-quality welds, general-quality welds and mechanical connections from high to low, the corresponding pipeline connection coefficients are 0.1, 1.0, 4.0 and 8.0 respectively.

9. The method according to any one of claims 1 to 8, characterized in that: The process of determining the severity of the consequences of a leak for each pipeline section to be evaluated includes: According to the maximum operating pressure and pipeline specifications of the pipeline to be evaluated, the radius of the potential impact area of ​​the current pipeline is determined. The radius of the current potential impact area is calculated using the following expression: Where r represents the affected radius, d represents the outer diameter of the pipeline, and p represents the maximum allowable operating pressure of the pipeline section; Count the casualties within the radius of the current potential impact area to determine the corresponding severity level of the consequences.

10. The method according to any one of claims 1 to 9, characterized in that: The step one comprises: Dividing the target pipeline into multiple sections of primary pipelines using the cut-off valve chamber as a dividing point; The pipelines laid in the form of crossing and spanning in each section of the primary pipeline are removed, so as to retain the pipelines laid in the form of buried in each section of the primary pipeline, so as to form the multiple sections of pipelines to be evaluated.

11. The method according to claim 10, characterized in that In the process of removing each section of primary pipeline according to different laying methods, If there are multiple discontinuous pipe sections in the same primary pipeline, these discontinuous pipe sections will be regarded as multiple pipeline sections to be evaluated; If there is only one pipe section in the same section of primary pipeline, then this pipe section is regarded as a pipe section to be evaluated.

12. A computer-readable storage medium, characterized in that: It contains a series of instructions for executing the method steps as claimed in any one of claims 1 to 11.

13. A system for evaluating the failure risk of buried pipelines in disaster-stricken areas, characterized in that: The system comprises: A pipeline segmentation module configured to divide the target pipeline into multiple segments and determine multiple segments of pipelines to be evaluated; A failure probability calculation module is configured to calculate the total probability of leakage risk caused by internal corrosion and geological disaster risks for each section of the pipeline to be evaluated, thereby obtaining the failure probability of the corresponding pipeline; a risk consequence calculation module configured to determine the severity of the leakage risk consequence of each section of the pipeline to be evaluated; The risk level generation module is configured to determine the risk level of the corresponding pipeline according to the failure possibility and leakage risk consequence severity of each section of the pipeline to be evaluated.

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