A method and system for evaluating failure risk of buried pipelines in geohazard areas

Abstract

The application discloses a method and system for evaluating failure risk of a buried pipeline in a geohazard area, comprising the following steps: dividing a target pipeline into multiple sections to determine multiple sections of the pipeline to be evaluated; calculating total leakage risk probabilities of each section of the pipeline to be evaluated caused by internal corrosion risk and geohazard risk respectively, so as to obtain failure likelihoods of the corresponding pipelines; determining leakage risk consequence severities of each section of the pipeline to be evaluated; and determining risk levels of the corresponding pipelines according to the failure likelihoods and the leakage risk consequence severities of each section of the pipeline to be evaluated. The application can enhance the pertinence of the failure risk evaluation of the buried pipeline in the geohazard area, and improve the level of safe operation management and technology of the buried pipeline.

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 evaluating the failure risk of buried pipelines in disaster-stricken areas. Background Art

[0002] With the sustained development of my country's national economy and the continuous optimization of its energy structure, natural gas, as a clean, environmentally friendly, and high-quality energy source, is gaining increasing attention. Natural gas has gradually assumed a pivotal position in my country's energy mix, and its consumption has continued to rise significantly. To ensure natural gas supply, my country has continuously increased its efforts in natural gas exploration and development in recent years. Currently, my country's natural gas pipeline network continues to expand. Gas field gathering and transmission pipelines, long-distance natural gas pipelines, and urban natural gas pipelines together form a "trunk interconnected and localized network" structure, with a total mileage exceeding one million kilometers. Although gas field gathering and transmission pipelines account for a relatively small proportion of this, natural gas leaks within these pipelines are common due to their complex external environment and harsh internal working conditions. If not discovered and properly addressed in a timely manner, these leaks can easily cause fires or explosions, posing a significant threat to business safety, public life, and property.

[0003] In recent years, the Sichuan-Chongqing region has gradually become one of my country's major oil and gas production hubs, with oil and gas fields being discovered and developed on a large scale. Due to its mountainous location and consistently high rainfall, the region is also a major target for geological disasters. Statistics show that landslides, mudslides, and other geological disasters in the region account for approximately 14% of similar disasters nationwide. These disasters can cause geological shifts and ground subsidence, which can loosen natural gas pipeline connections and lead to gas leaks. Furthermore, buried pipelines constructed in these disaster-prone areas face the widespread risk of corrosion and perforation, leading to gas leaks.

[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 buried pipelines is provided. The method includes: a pre-evaluation step for detecting internal corrosion of buried pipelines; an indirect detection and evaluation step for internal corrosion of buried pipelines; a direct detection and evaluation step for internal corrosion of buried pipelines; and a step for evaluating the effectiveness of the direct internal corrosion evaluation (ICDA) of buried pipelines and determining a time for re-evaluation. This method improves the level of safe operation management and technology of buried pipelines, can reduce economic losses to personnel and facilities caused by sudden accidents, and ensure safe production.

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

[0007] However, the existing technology only considers one risk to establish calculation models and risk assessment methods, 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 and 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 proposes a technical solution for evaluating the failure risk of buried pipelines in geological disaster areas.

[0010] To address the above technical issues, an embodiment of the present invention provides a method for evaluating the failure risk of buried pipelines in geological disaster areas, comprising: step 1: dividing a target pipeline into multiple sections to determine multiple sections of pipeline to be evaluated; step 2: calculating the total probability of leakage risk caused by internal corrosion and geological disaster risk for each section of pipeline to be evaluated, thereby obtaining the failure probability of the corresponding pipeline; step 3: determining the severity of the consequences of the leakage risk for each section of pipeline to be evaluated; and step 4: determining the risk level of the corresponding pipeline based on the failure probability and the severity of the consequences of the leakage risk for each section of pipeline to be evaluated.

[0011] Preferably, the second step includes: respectively calculating the risk probability of small hole internal corrosion leakage, the risk probability of medium hole internal corrosion leakage and the risk probability of fracture internal corrosion leakage 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 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 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; based on 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, 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 based on the initial effectiveness of the internal detection, the internal detection execution time, the internal detection time increment, and the internal detection validity period of the pipeline to be evaluated, 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 corrosiveness factor of the gathering and transportation medium based on 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 corrosiveness factor of the gathering and transportation medium 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 using 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 Indicates the risk probability of corrosion leakage in the pipeline, RB 内腐蚀 Indicates the baseline probability of corrosion leakage risk in pipelines, 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 pipeline wall thickness, FPC represents the corrosiveness factor of the gathering and transportation medium, k represents the leakage degree correction factor of different failure modes, and L represents the pipeline length. The effective life of internal corrosion is expressed 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, τ b Indicates the validity period of 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 medium corrosivity factor is: when the electric fingerprint corrosion rate is less than 0.02, the gathering medium corrosivity 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 medium corrosivity 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 medium corrosivity 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 medium corrosivity factor is 5.0; when the electric fingerprint corrosion rate is greater than or equal to 2.5, the gathering medium corrosivity factor is 6.0.

[0020] Preferably, the process of calculating the total probability of geological disaster leakage risk of each section of the pipeline to be evaluated includes: determining a corresponding geological disaster warning coefficient based on the geological disaster warning level of the pipeline to be evaluated; determining a pipeline failure frequency based on the pipeline failure level of the pipeline to be evaluated; determining a pipeline connection coefficient based on the pipeline weld quality level of the pipeline to be evaluated; calculating the geological disaster leakage risk probability of different failure modes 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 modes and the pipeline length; and determining the total geological disaster leakage risk probability of the pipeline to be evaluated as 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.

[0021] Preferably, the probability of geological disaster leakage risk of different failure modes is expressed using 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 geological disaster leakage correction factors 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, the process of determining the severity of the consequences of the leakage risk of each section of the pipeline to be evaluated includes: determining the radius of the potential impact area of ​​the current pipeline according to the maximum operating pressure and pipeline specifications of the pipeline to be evaluated, 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. 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 shut-off valve chamber as the 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 sections of pipe in the same section of primary pipeline, these discontinuous sections of pipe are regarded as multiple sections of pipeline to be evaluated; if there is only one section of pipe in the same section of primary pipeline, this section of pipe 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, comprising: a pipeline segmentation module configured to divide a target pipeline into multiple sections and determine multiple sections of pipelines to be evaluated; a failure probability calculation module 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 consequences of each section of the pipeline to be evaluated; and a risk level generation module configured to determine the risk level of the corresponding pipeline based on the failure probability 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 solutions 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 existing pipeline risk assessment methods do not take into account the situation where pipeline leakage failures caused by pipeline corrosion and geological disasters. By using an internal corrosion failure probability calculation model, a geological disaster failure probability calculation model, and a 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 the pipeline leakage risk. 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 in part will become apparent from the description, or will be understood by practicing the present invention. The purposes 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 the 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 the failure risk of buried pipelines in disaster-stricken areas according to an embodiment of the present application. DETAILED DESCRIPTION

[0040] The following describes the embodiments of the present invention in detail with reference to the accompanying drawings and examples, so that the present invention can fully understand how to apply technical means to solve technical problems and achieve technical effects, and thus implement the invention accordingly. It should be noted that, as long as no conflict exists, the various embodiments of the present invention and the various features of the embodiments can be combined with each other, and the resulting technical solutions are all within the scope of protection 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 order is shown in the flowchart, in some cases, the steps shown or described can be performed in a different order than here.

[0042] The terms used herein are intended only to describe specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "a", "an", "an item" used herein are also intended to include the plural. It should also be understood that the terms "comprise" and / or "include" used herein specify the presence of stated features, integers, steps, operations, units and / or components, and do not preclude the presence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0043] In recent years, the Sichuan-Chongqing region has gradually become one of my country's major oil and gas production hubs, with oil and gas fields being discovered and developed on a large scale. Due to its mountainous location and consistently high rainfall, the region is also a major target for geological disasters. Statistics show that landslides, mudslides, and other geological disasters in the region account for approximately 14% of similar disasters nationwide. These disasters can cause geological shifts and ground subsidence, which can loosen natural gas pipeline connections and lead to gas leaks. Furthermore, buried pipelines constructed in these disaster-prone areas face the widespread risk of corrosion and perforation, leading to gas leaks.

[0044] To address the aforementioned issues, the present invention proposes a solution for assessing the failure risk of buried pipelines in disaster-stricken areas. This solution fully considers the dual risks of corrosion and geological disasters affecting buried pipelines. By using internal corrosion failure probability calculation models, geological disaster failure probability calculation models, and coupled failure probability calculation models, the solution calculates the probability of pipeline failure based on the dual risks of corrosion and geological disasters. Furthermore, by combining the severity of the consequences of pipeline leakage risks, the solution effectively quantifies the pipeline risk level, thereby enhancing the targeted nature of risk assessments and improving the safety management and technology of buried pipeline operations.

[0045] Example 1

[0046] Figure 1 Schematic diagram of the steps of a method for evaluating the 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 the embodiment of the present invention is described in detail.

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

[0048] First, the target pipeline network in the disaster-stricken area was divided into multiple primary pipeline sections using the cutoff valve chamber as the demarcation point. The primary pipeline was then further divided into multiple sections based on different laying types. Within each section, sections laid in a crossing or spanning manner were eliminated, leaving only the buried sections within each primary pipeline section, forming multiple pipeline sections to be evaluated.

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

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

[0051] Figure 3 This 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. Figure 3As shown, in step S110, the gathering and transportation pipeline network in the disaster area is first divided into n sections, using the intercepting valve chambers of the network as the dividing points. A primary pipeline section is formed between each two intercepting valve chambers. If the first section of the primary pipeline contains tunnel pipelines laid in a through-type manner and truss pipelines laid in a spanning manner, the tunnel pipelines and truss pipelines are removed, and only three sections of buried pipeline are retained as the pipeline to be evaluated, namely Section 1-1, Section 1-2, and Section 1-3. If the second section of the primary pipeline contains only one buried pipeline section, the entire section is designated as the second pipeline to be evaluated.

[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, thereby obtaining 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, internal corrosion-induced pipeline leakage occurs in three different failure modes: small-hole internal corrosion leakage, medium-hole internal corrosion leakage, and fracture internal corrosion leakage. Therefore, a pipeline internal corrosion leakage risk calculation model is needed to calculate the leakage risk probabilities of each of these three failure modes, thereby deriving the total internal corrosion leakage risk probability for the pipeline under evaluation.

[0056] That is, in step S120, the risk probabilities 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 the leakage risk probabilities of these three failure modes, 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 inspection time correction factor based on the initial effectiveness of the internal inspection, the internal inspection execution time, the internal inspection time increment, and the internal inspection validity period of the pipeline to be evaluated, and calculating the effective years of internal corrosion based on the internal inspection time correction factor in combination with the pipeline operation years and the internal inspection time increment; determining the corrosiveness factor of the gathering and transportation medium based on 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 corrosiveness factor of the gathering and transportation medium, 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 total probability of internal corrosion leakage risk of the pipeline to be evaluated as 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.

[0058] The calculation model for 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 pipelines, dimensionless; 内腐蚀 represents the proportional coefficient of the internal corrosion leakage risk model, dimensionless; τ 内腐蚀 = represents the effective lifespan of internal corrosion in pipelines; t represents the wall thickness of the pipeline in millimeters; FPC represents the corrosiveness factor of the gathering and transportation medium, which is dimensionless; k represents the leakage correction factor for different failure modes, which is dimensionless; L represents the length of the pipeline in kilometers. The effective lifespan of internal corrosion in pipelines is expressed using the following expression:

[0061] τ 内腐蚀 =λ×(τ a +Δτ) (2)

[0062]

[0063] Where λ is the internal detection time correction factor, which is dimensionless; β is 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 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 specific relationship between the electrical fingerprint corrosion rate and the gathering medium corrosivity factor is 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) Gathering and transportation medium corrosion factor 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 degree 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 small holes; R 内腐蚀中孔泄漏 Indicates 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 It represents the total probability of internal corrosion leakage risk of the pipeline to be evaluated.

[0081] Secondly, pipeline leakage caused by geological disasters can occur in three different failure modes: small-hole leakage, medium-hole leakage, and fracture leakage. Therefore, a pipeline geological disaster leakage risk calculation model is needed to calculate the leakage risk probabilities of each of these three failure modes, thereby deriving the total geological disaster leakage risk probability for the pipeline under evaluation.

[0082] That is, step S120 also needs to calculate the risk probability of small-hole geological disaster leakage, medium-hole geological disaster leakage and fracture geological disaster leakage 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 for each section of the pipeline to be evaluated includes: determining the corresponding geological disaster warning coefficient based on the geological disaster warning level of the pipeline to be evaluated; determining the pipeline failure frequency based on the pipeline failure level of the pipeline to be evaluated; determining the pipeline connection coefficient based on the pipeline weld quality level of the pipeline to be evaluated; calculating the geological disaster leakage risk probability of different failure modes 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 modes and the pipeline length; and determining the total geological disaster leakage risk probability of the pipeline to be evaluated as 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.

[0084] 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 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, from low to high, attention level, warning level, alert level, and alarm level. In one embodiment, the correspondence between the geological disaster warning level and the geological disaster warning coefficient is 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 Geological 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, from low to high, low failure level, medium failure level, and high failure level. In one embodiment, the corresponding relationship between the pipeline failure level and the pipeline failure frequency is 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 joint coefficient (FJNT) is determined by the quality of the pipeline weld. Pipeline weld quality levels, from high to low, are high-quality weld, medium-quality weld, average-quality weld, and mechanical joint. In one embodiment, the corresponding relationship between pipeline weld quality and the pipeline joint coefficient is 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 represents the risk probability of small hole geological disaster leakage; R 内腐蚀中孔泄漏 R represents the probability of leakage risk of medium-sized geological disasters; 内腐蚀断裂泄漏 Indicates the risk probability of leakage from fault disasters.

[0104] Furthermore, based on 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 leakage risk probability 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 Indicates the total probability of leakage risk of the target pipeline.

[0110] Furthermore, based on the total probability of pipeline leakage risk, the pipeline failure probability level is determined. In this embodiment of the present invention, to facilitate risk management, a range of probability levels corresponding to the probability of pipeline failure in a disaster-stricken area is defined. In one embodiment, the correspondence between the total probability of pipeline failure in a disaster-stricken area and the probability level is shown in Table 6.

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

[0112] Total probability of pipeline failure in disaster-stricken areas Likelihood level <![CDATA[Total leakage risk ≤ 10 -6 > 1 <![CDATA[10 -6 <R total leakage risk ≤ 10 -5 ]]> 2 <![CDATA[10 -5 <R total leakage risk ≤ 10 -4 ]]> 3 <![CDATA[10 -4 <R total leakage risk ≤ 10 -3 ]]> 4 <![CDATA[10 -3 <R total leakage risk ≤ 10 -2 ]]> 5 <![CDATA[10 -2 <R total 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, the radius of the potential impact area of ​​the pipeline under evaluation is first determined based on the pipeline's maximum operating pressure and pipeline specifications. A population survey is then conducted within the radius of the impact area to determine casualties. Based on the casualties, a consequence level is determined to determine the severity of the leakage risk consequences of the pipeline under evaluation.

[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 meters; d represents the outer diameter of the pipeline, in millimeters; 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 long-distance natural gas 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 based on the pipeline specifications and the maximum operating pressure of the pipeline section to be evaluated. The corresponding relationship between common pipeline specifications, operating pressures, and impact radius for 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, based on the radius of the pipeline's potential impact area, a population survey is conducted to obtain casualties of people around the target pipeline section, and then determine the consequence level.

[0126] In one embodiment, the consequence levels are divided into seven levels 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 pipeline section to be evaluated based on the failure probability and leakage risk consequence severity of each pipeline section to be evaluated.

[0131] In step S140, a risk value is determined based on the failure probability level and the severity level of the leakage risk consequence of the pipeline to be evaluated. Then, based on 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 likelihood 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, high risk, and serious risk. The correspondence between risk level and risk value is shown in Table 11.

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

[0138]

[0139]

[0140] Example 2

[0141] Based on the above-mentioned embodiment 1, a failure risk assessment method for section A of a gathering and transportation pipeline in northeastern Sichuan is given below.

[0142] S1 pipeline segmentation. Pipeline segment A is located between valve chambers 1 and 2, with a total length of 5 km. A truss is located in the middle of the segment. Pipeline segment A is divided into two sections, A-1 and A-2, with lengths of 2.0 km and 1.8 km, respectively. Section A-1 is selected for risk assessment.

[0143] S2 calculates the total probability of internal corrosion leakage risk. Based on pipeline design information, corrosion monitoring data, internal inspection data, and production and operation conditions, relevant data are comprehensively assigned values, as shown in Table 12.

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

[0145]

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

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

[0148] Substituting the above data into formula (4), formula (5) and formula (6), we can obtain the risk probability of corrosion leakage in the small hole as 4.11×10 -5 The 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 relationships of 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 13.

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

[0155]

[0156] Substituting the above data into formulas (9), (10), and (11), we can obtain 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. The total risk probability of geological disaster leakage for the A-1 pipeline is calculated as 0.0132 using formula (12).

[0157] S4 determines the failure probability level of the pipeline. According to formula (13), the total probability of leakage risk of corrosion in pipeline A-1 and the total probability of leakage risk of geological disaster in pipeline A-1 are added together to calculate the total probability of leakage risk of pipeline A-1 to be 1.325×10 -2 According to Table 6, the failure probability level of the A-1 pipeline can be determined to be level 6.

[0158] S5 determines the consequence level of pipeline failure and leakage. Based on the specifications of the A-1 pipeline, which is Φ219.110 and has an operating pressure of 8.6 MPa, and Table 8, the impact radius of a leak is 292 meters. According to population survey data, with the A-1 pipeline axis as the axis, the permanent population within 292 meters of the pipeline is 6. A pipeline leak and fire explosion would result in at least 2 deaths and 4 serious injuries. Based on Table 9, the consequence level of a pipeline failure and leakage is determined to be D.

[0159] S6 Risk Quantification and Grading. Table 10 shows that when the likelihood of a leak in the A-1 pipeline is 6 and the consequence is D, the corresponding risk value is 37. Based on the relationship between risk levels and risk values ​​given in Table 11, the risk level is determined to be orange (high risk).

[0160] Example 3

[0161] Based on the above-mentioned embodiment 1, 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. Segment B, located between valve chambers 5 and 6, is 4.3 km long. A truss and a tunnel are located in the middle of the segment. Segment B 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. Segment B-1 is selected for risk assessment.

[0163] S2 calculates the total probability of internal corrosion leakage risk. Based on pipeline design information, corrosion monitoring data, internal inspection data, and production and operation conditions, relevant data are comprehensively assigned values, as shown in Table 14.

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

[0165] Serial number parameter Representative symbols 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 operating life <![CDATA[τ a ]]> Year 7 8 Pipe diameter / wall thickness t mm Φ273*12.5 9 Electrical fingerprint corrosion rate / mm / a 1.0 10 Pipe section length L Km 1

[0166] The electric fingerprint corrosion rate CR = 1.0 mm / a, and 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 corrosion life of the pipeline is calculated to be 3.06 years.

[0168] Substituting the above data into formula (4), formula (5) and formula (6), we can obtain the risk probability of corrosion leakage in the small hole as 1.5×10 -5 The 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] Combined with the corresponding relationships of 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 on geological disaster leakage risk of pipeline B-1

[0175]

[0176] Substituting the above data into formula (9), formula (10) and formula (11), we can obtain the risk probability of small hole geological disaster leakage as 5×10 -6 The probability of leakage from a geological disaster in the middle 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 of corrosion in pipeline B-1 and the total probability of leakage risk of geological disaster in pipeline B-1 are added together to calculate the total probability of leakage risk of pipeline B-1 to be 4.5×10 -5According to Table 6, the failure probability level of the B-1 pipeline can be determined to be level 3.

[0178] S5 determines the consequence level of a pipeline failure or leakage. Based on the specifications of the B-1 pipeline (Φ273*12.5) and the operating pressure of 8.5 MPa, combined with Table 8, the impact radius of a leak is 380 meters. According to population survey data, with the B-1 pipeline as the axis, the permanent population within 380 meters of the pipeline is 2 people. A pipeline leak, fire, or explosion would result in at least two minor injuries. Combined with Table 9, the consequence level of a pipeline failure or leakage is determined to be B.

[0179] S6 Risk Quantification and Grading. Table 10 shows that when the B-1 pipeline leak probability level is 3 and the consequence level is B, the corresponding risk value is 3. Based on the corresponding relationship between risk levels and risk values ​​given in Table 11, the risk level can be determined to be blue, low risk.

[0180] Example 4

[0181] Based on the above-mentioned embodiment 1, 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. Segment C, located between valve chambers 6 and 7, is 9 km long. One truss and two tunnels are located in the middle of the segment. Segment C is divided into four sections: C-1, C-2, C-3, and C-4, with lengths of 1.0 km, 0.6 km, 4.5 km, and 1.8 km, respectively. Segment C-3 is currently selected for risk assessment.

[0183] S2 calculates the total probability of internal corrosion leakage risk. Based on pipeline design information, corrosion monitoring data, internal inspection data, and production and operation conditions, the relevant data are comprehensively assigned values, as shown in Table 16.

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

[0185]

[0186]

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

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

[0189] Substituting the above data into formula (4), formula (5) and formula (6), we can obtain the risk probability of corrosion leakage in the small hole as 6.59×10-4 The 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 relationships of 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 17.

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

[0196]

[0197] Substituting the above data into formulas (9), (10), and (11), we can obtain 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. The total risk probability of geological disaster leakage for the C-3 pipeline is calculated as 0.3168 according to formula (12).

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

[0199] S5 determines the consequence level of pipeline failure and leakage. Based on the specifications of the C-3 pipeline (Φ457*28), operating pressure of 9.3 MPa, and Table 8, the impact radius of a leak is 1050 m. According to population survey data, with the C-3 pipeline as the axis, the permanent population within a 1050-meter radius of the pipeline is 10. A pipeline leak, fire, or explosion would result in at least three deaths. Based on Table 9, the consequence level of a pipeline failure and leakage is determined to be E.

[0200] S6 Risk Quantification and Grading. Table 10 shows that when the likelihood level of the C-3 pipeline leak is 7 and the consequence level is E, the corresponding risk value is 68. Based on the corresponding relationship between risk levels and risk values ​​given in Table 11, the risk level can be determined to be a red major risk.

[0201] Example 5

[0202] Based on the above-mentioned embodiment 1, 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. Segment D is located between valve chambers 6 and 7, with a total length of 2 km. A tunnel exists in the middle of the segment. Segment D is divided into two sections, D-1 and D-2, with lengths of 0.5 km and 0.8 km, respectively. Segment D-2 is selected for risk assessment.

[0204] S2 calculates the total probability of internal corrosion leakage risk. Based on pipeline design information, corrosion monitoring data, internal inspection data, and production and operation conditions, the relevant data are comprehensively assigned values, as shown in Table 18.

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

[0206] Serial number parameter Representative symbols 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 operating 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 section length L Km 0.8

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

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

[0209] Substituting the above data into formula (4), formula (5) and formula (6), we can obtain 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 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 relationships of 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 19.

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

[0216]

[0217] Substituting the above data into formula (9), formula (10) and formula (11), we can obtain the risk probability of small hole geological disaster leakage as 8×10 -6 The probability of leakage from a geological disaster in the middle 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 due to geological disaster is calculated to be 4.4×10 -5 .

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

[0219] S5 determines the consequence level of pipeline failure and leakage. Based on the specifications of the D-2 pipeline (Φ168.3*8.8), the operating pressure (8.8 MPa), and Table 8, the impact radius of a leak is 230 meters. According to population survey data, the permanent population within 230 meters of the D-2 pipeline axis is 20. A pipeline leak, fire, or explosion would result in at least four deaths and ten serious injuries. Based on Table 9, the consequence level of a pipeline failure and leakage is determined to be E.

[0220] S6 Risk Quantification and Grading. Table 10 shows that when the D-2 pipeline leak probability level is 3 and the consequence level is E, the corresponding risk value is 15. Based on the corresponding relationship between risk levels and risk values ​​given in Table 11, the risk level can be determined to be yellow general risk.

[0221] Example 6

[0222] Based on the above-mentioned embodiment 1, a failure risk assessment method for section a of a gathering and transportation pipeline in western Sichuan is given below.

[0223] S1 pipeline segmentation. Pipeline segment a is located between valve chambers a1 and a2, with a total length of 3.9 km. A truss and a tunnel are located in the middle of the segment. Pipe segment a 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. Section a-3 is selected for risk assessment.

[0224] S2 calculates the total probability of internal corrosion leakage risk. Based on pipeline design information, corrosion monitoring data, internal inspection data, and production and operation conditions, the relevant data are comprehensively assigned values, as shown in Table 20.

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

[0226] Serial number parameter Representative symbols 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 operating life <![CDATA[τ a ]]> Year 10 8 Pipe diameter / wall thickness t mm Φ406.4*17.5 9 Electrical fingerprint corrosion rate / mm / a 1.2 10 Pipe section length L Km 1.8

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

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

[0229] Substituting the above data into formula (4), formula (5) and formula (6), we can obtain 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 relationships of 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 geological disaster leakage risk of pipeline a-3

[0236]

[0237] Substituting the above data into formula (9), formula (10) and formula (11), we can obtain the risk probability of small hole geological disaster leakage as 21.6×10 -5 The risk probability of leakage from a geological disaster in the middle 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 geological disaster is calculated to be 118.8×10 -5 .

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

[0239] S5 determines the consequence level of pipeline failure and leakage. Based on the specifications of the a-3 pipeline (Φ406.4 x 17.5 mm) and the operating pressure of 8.4 MPa, combined with Table 8, the impact radius of a leakage is 800 m. According to population survey data, with the a-3 pipeline as the axis, the permanent population within 800 meters of the pipeline is 5. A pipeline leakage, fire, or explosion would result in at least one death and three serious injuries. Combined with Table 9, the consequence level of a pipeline failure and leakage is determined to be D.

[0240] S6 Risk Quantification and Grading. Table 10 shows that when the likelihood of a-3 pipeline leakage is 5 and the consequence is D, the corresponding risk value is 25. Based on the corresponding relationship between risk levels and risk values ​​given in Table 11, the risk level is determined to be orange, high risk.

[0241] Example 7

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

[0243] S1 pipeline segmentation. Segment b, located between valve chambers b3 and b4, is 2.3 km long and contains no trusses or tunnels. A risk assessment is now underway for segment b.

[0244] S2 calculates the total probability of internal corrosion leakage risk. Based on pipeline design information, corrosion monitoring data, internal inspection data, and production and operating conditions, the relevant data are comprehensively assigned values, as shown in Table 22.

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

[0246] Serial number parameter Representative symbols 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 operating 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 section length L Km 2.3

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

[0248] According to formula (2) and formula (3), the effective corrosion life of the pipeline 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] Combined with the corresponding relationships of 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 formulas (9), (10), and (11), we can obtain 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. The total risk probability of geological disaster leakage for pipeline b is calculated using formula (12) to be 0.004554.

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

[0259] S5 determines the consequence level of a pipeline failure or leakage. Based on the specifications of the pipeline in section b (Φ323.9 x 14.2 mm) and the operating pressure of 8.4 MPa, combined with Table 8, the impact radius of a leak is 450 meters. According to population survey data, with section b as the axis, the permanent population within 450 meters of the pipeline is 3. A pipeline leak, fire, or explosion would result in at least one serious injury and three minor injuries. Combined with Table 9, the consequence level of a pipeline failure or leakage is determined to be C.

[0260] S6 Risk Quantification and Grading. Table 10 shows that when the likelihood of a leak in pipeline b is 5 and the consequence is C, the corresponding risk value is 11. Based on the corresponding relationship between risk levels and risk values ​​given in Table 11, the risk level is determined to be yellow, general risk.

[0261] Example 8

[0262] Based on the above-mentioned embodiment 1, 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 Section I is located between valve chambers H2 and H3, with a total length of 7.7 km. A truss and a tunnel are located in the middle of the section. Section I is divided into three sections: I-1, I-2, and I-3, with lengths of 2.0 km, 2.5 km, and 1.8 km, respectively. Section I-1 is currently selected for risk assessment.

[0264] S2 calculates the total probability of internal corrosion leakage risk. Based on pipeline design information, corrosion monitoring data, internal inspection data, and production and operation conditions, the relevant data are comprehensively assigned values, as shown in Table 24.

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

[0266]

[0267]

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

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

[0270] Substituting the above data into formula (4), formula (5) and formula (6), we can obtain the risk probability of corrosion leakage in the small hole as 5.974×10 -5 The probability of corrosion leakage in the middle hole is 7.03×10 -6The 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] Combined with the corresponding relationships of 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 on geological disaster leakage risk of pipeline I-1

[0277]

[0278] Substituting the above data into formulas (9), (10), and (11), we can obtain 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 for 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 corrosion leakage risk in pipeline I-1 is added to the total probability of geological disaster leakage risk in pipeline I-1, and the total probability of leakage risk in pipeline I-1 is calculated to be 4.47×10 -3 According to Table 6, the failure probability level of the Ⅰ-1 pipeline is determined to be level 5.

[0280] S5 determines the consequence level of pipeline failure and leakage. Based on the specifications of the pipeline in Section I-1 (Φ508*22.2) and the operating pressure of 9.1 MPa, combined with Table 8, the impact radius of a leak is 1350 meters. According to population survey data, with Section I-1 as the axis, the permanent population within a 1350-meter radius of the pipeline is 50. A pipeline leak, fire, or explosion would result in at least 15 deaths and 20 serious injuries. Combined with Table 9, the consequence level of a pipeline failure and leakage is determined to be F.

[0281] S6 Risk Quantification and Grading. Table 10 shows that when the likelihood of a leak in the I-1 pipeline is 5 and the consequence is F, the corresponding risk value is 43. Based on the corresponding relationship between risk levels and risk values ​​given in Table 11, the risk level is determined to be a red, significant risk.

[0282] Embodiment 9

[0283] Based on the above-described methods for assessing the failure risk of buried pipelines in disaster-stricken areas, embodiments 1 to 8, the present invention also provides a computer-readable storage medium having a computer program stored thereon. The computer program is executed to execute a method for assessing the failure risk of buried pipelines in disaster-stricken areas. The computer program is capable of executing computer instructions, which include computer program code. The computer program code may be in source code form, object code form, an executable file, or some intermediate form.

[0284] Computer-readable storage media may include: any entity or device that can carry computer program code, recording media, USB flash drives, mobile hard drives, 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 electric carrier signals and telecommunication signals.

[0286] Example 10

[0287] Based on the methods for assessing the failure risk of buried pipelines in disaster-stricken areas described in Examples 1 to 8 above, the present invention further provides a system for assessing the failure risk of buried pipelines in disaster-stricken areas. The system is used to implement the methods for assessing the failure risk of buried pipelines in disaster-stricken areas described in Examples 1 to 8 above.

[0288] Figure 4 This is a 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 according to the embodiment of the present invention includes: a pipeline segmentation module 401 , a failure probability 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 step S110 above, and is configured to divide the target pipeline into multiple sections to determine multiple sections of pipeline to be evaluated. The failure probability calculation module 402 is implemented according to the method described in step S120 above, and is configured to calculate the total probability of leakage risk caused by internal corrosion and geological disaster risks for each section of pipeline to be evaluated, thereby obtaining the failure probability of the corresponding pipeline. The risk consequence calculation module 403 is implemented according to the method described in step S130 above, and is configured to determine the severity of the leakage risk consequences of each section of pipeline to be evaluated. The risk level generation module 404 is implemented according to the method described in step S140 above, and is configured to determine the risk level of the corresponding pipeline based on the failure probability and the severity of the leakage risk consequences of each section of 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. This method and system solves the problem that existing pipeline risk assessment methods do not take into account the failure of pipelines due to leakage caused by pipeline corrosion and geological disasters. By using an internal corrosion failure probability calculation model, a geological disaster failure probability calculation model, and a 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 the pipeline leakage risk. 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.

[0291] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by anyone skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

[0292] In the description of the present invention, unless otherwise specified, "plurality" means two or more; terms such as "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," and "tail" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0293] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integral connection; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0294] It should be understood that the embodiments disclosed herein are not limited to the specific structures, processing steps, or materials disclosed herein, but should extend to equivalent substitutions of these features understood by those skilled in the relevant art. It should also be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to be limiting.

[0295] References in this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Therefore, appearances of the phrases "one embodiment" or "an embodiment" in various places throughout this specification do not necessarily refer to the same embodiment.

[0296] Although the embodiments disclosed above are for facilitating understanding of the present invention, the contents described are merely embodiments adopted for facilitating understanding of the present invention and are not intended to limit the present invention. Any person skilled in the art of the present invention may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope of the present invention. However, the scope of patent protection of the present invention shall still be subject to the scope defined by the appended 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 risk for each section of pipeline to be evaluated, thereby obtaining the failure probability of the corresponding pipeline, including: calculating the small hole internal corrosion leakage risk probability, medium hole internal corrosion leakage risk probability and fracture internal corrosion leakage risk probability caused by internal corrosion of each section of pipeline to be evaluated, based on which the total probability of internal corrosion leakage risk of each section of pipeline to be evaluated is obtained; and calculate the internal corrosion leakage risk probability of different failure modes in 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 proportional coefficient of the internal corrosion leakage risk model, the pipeline wall thickness, the internal corrosion leakage degree correction factor of different failure modes and the pipeline length. The internal corrosion leakage risk probability of different failure modes is expressed by the following expression: in, R 内腐蚀 Indicates the probability of corrosion leakage risk in the pipeline, RB 内腐蚀 Indicates the baseline probability of corrosion leakage risk in pipelines, K 内腐蚀 represents the proportional coefficient of the internal corrosion leakage risk model; τ 内腐蚀 Indicates the effective corrosion life of the pipeline. t Indicates the pipe wall thickness, FPC Indicates the corrosiveness factor of the gathering and transportation medium, k Leakage correction factors representing different failure modes, L represents the length of the pipeline, wherein the effective life of internal corrosion is expressed by the following expression: in, represents the internal detection time correction factor, Indicates the initial effectiveness of in-pipeline detection, Indicates the operating life of the pipeline, ∆τ represents the time increment, Indicates the validity period of the pipeline inspection. Indicates the execution time of corrosion detection; Step 3: Determine the severity of the leakage risk consequences of each section of pipeline to be evaluated; Step 4: Determine the risk level of the corresponding pipeline based on the failure probability and leakage risk severity of each section of the pipeline to be evaluated.

2. The method according to claim 1, characterized in that The second step also includes: Calculate the risk probability of small-hole geological disaster leakage, medium-hole geological disaster leakage and fracture geological disaster leakage caused by geological disasters for each section of the pipeline to be evaluated respectively. Based on this, the total geological disaster leakage risk probability 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 also includes: Determine an internal inspection time correction factor based on 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 based on 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 based on the electrical fingerprint corrosion rate of the pipeline to be evaluated; 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 correction factors for internal corrosion leakage levels for 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 corrosivity factor of the gathering and transportation medium is: When the electric fingerprint corrosion rate is less than 0.02, the corrosivity factor of the gathering and transportation medium is 0.04; When the electric fingerprint corrosion rate is greater than or equal to 0.02 and less than 0.1, the corrosivity 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.

5. The method according to any one of claims 1 to 4, 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 based on the pipeline failure level of the pipeline to be evaluated; Determine the pipeline connection coefficient based on the pipeline weld quality grade of 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 baseline probability of geological disaster pipeline failure risk, the correction factor of the geological disaster leakage degree of different failure modes and the pipeline length, the geological disaster leakage risk probability of different failure modes 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.

6. The method according to claim 5, characterized in that The probability of geological disaster leakage risk in different failure modes is expressed by the following expression: in, 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 pipe connection coefficient, a Indicates the leakage correction factor, L Indicates the length of the pipe.

7. The method according to claim 5, characterized in that The correction factors for the leakage degree of geological disasters for small holes, medium holes, and faults 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 grades from high to low are high-quality welds, medium-quality welds, general-quality welds and mechanical connections, the corresponding pipeline connection coefficients are 0.1, 1.0, 4.0 and 8.0 respectively.

8. The method according to any one of claims 1 to 4, characterized in that The process of determining the severity of the consequences of leakage risks for each pipeline section to be evaluated includes: Based on the maximum operating pressure and pipeline specifications of the pipeline to be evaluated, determine the radius of the current pipeline's potential impact area. The radius of the current potential impact area is calculated using the following expression: in, r represents the affected radius, d Indicates the outer diameter of the pipe, p Indicates the maximum allowable operating pressure of the pipe section; Count the casualties within the radius of the current potential impact area to determine the corresponding severity level of the consequences.

9. The method according to any one of claims 1 to 4, characterized in that The step one comprises: Dividing the target pipeline into multiple primary pipeline sections using the cutoff 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, thereby retaining 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.

10. The method according to claim 9, 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 within the same primary pipeline, these discontinuous pipe sections will be considered as multiple pipeline sections to be evaluated; If there is only one pipe section in the same primary pipeline, then this pipe section will be regarded as a pipe section to be evaluated.

11. A computer-readable storage medium, characterized in that It contains a series of instructions for executing the method steps according to any one of claims 1 to 10.

12. 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 pipeline 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 based on the failure probability and the severity of the leakage risk consequences of each section of the pipeline to be evaluated, wherein the failure probability calculation module is further configured to: The 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 pipeline to be evaluated is calculated respectively. Based on this, the total probability of internal corrosion leakage risk of each section of pipeline to be evaluated is obtained. In addition, the probability of internal corrosion leakage risk of different failure modes in the pipeline to be evaluated is calculated based on 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 proportional coefficient of the internal corrosion leakage risk model, the pipeline wall thickness, the correction factor of the internal corrosion leakage degree of different failure modes and the pipeline length. The internal corrosion leakage risk probability of different failure modes is expressed by the following expression: in, R 内腐蚀 Indicates the probability of corrosion leakage risk in the pipeline, RB 内腐蚀 Indicates the baseline probability of corrosion leakage risk in pipelines, K 内腐蚀 represents the proportional coefficient of the internal corrosion leakage risk model; τ 内腐蚀 Indicates the effective corrosion life of the pipeline. t Indicates the pipe wall thickness, FPC Indicates the corrosiveness factor of the gathering and transportation medium, k Leakage correction factors representing different failure modes, L represents the length of the pipeline, wherein the effective life of internal corrosion is expressed by the following expression: in, represents the internal detection time correction factor, Indicates the initial effectiveness of in-pipeline detection, Indicates the operating life of the pipeline, ∆τ represents the time increment, Indicates the validity period of the pipeline inspection. Indicates the execution time of corrosion detection.

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