Oil and gas pipeline hoisting construction circumferential weld stress analysis method
A three-dimensional model-based method for stress analysis on girth welds during oil and gas pipeline hoisting improves accuracy and prevents damage by simulating stress and deformation conditions.
Patent Information
- Application Number
- CN202411111703.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-14
- Publication Date
- 2024-12-13
AI Technical Summary
Existing technologies are unable to accurately perform stress analysis on girth welds of oil and gas pipelines during hoisting construction, leading to potential cracking and damage due to insufficient consideration of key parameters.
A method involving the construction of a three-dimensional girth weld entity model using pipeline, trench, and hoisting process parameters to simulate and analyze stress and deformation, incorporating boundary loads to determine stress and deformation conditions.
Enhances the accuracy of stress analysis on girth welds, preventing damage by identifying vulnerable areas and improving safety during hoisting construction.
Smart Images
Figure CN119129040A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of stress analysis, and in particular to a method for analyzing the stress of a girth weld during oil and gas pipeline hoisting construction. Background Art
[0002] With the large-scale construction of high-pressure, large-diameter, and high-grade steel pipelines, higher requirements and huge challenges have been brought to the inherent safety of pipeline operation. Therefore, it is necessary to strengthen the safety verification of the oil and gas pipeline construction process from the construction period to fundamentally ensure the quality of the oil and gas pipeline project. During the construction of buried oil and gas pipelines, an important part is the lifting and trenching operation of the oil and gas pipelines.
[0003] The oil and gas pipeline will be subjected to bending and axial stress during the process of hoisting and trenching. Under unreasonable hoisting stress, the pipeline weld and parent material will undergo plastic deformation. In particular, the weld will have the possibility of forming cracks under low-temperature hoisting stress, and even cause the oil and gas pipeline to break.
[0004] At present, relevant technologies have conducted relevant research on the influence of pipeline stress during the hoisting construction process. For example, the main influencing factors of the oil and gas pipeline trenching process and the influence of the oil and gas pipeline trenching process on pipeline stress have been studied and analyzed, and a prediction method for the hoisting trenching process has been formed. However, the influence of the key parameters of the hoisting trenching on the cracking of the girth weld cannot be determined, resulting in insufficient support for stress control of the oil and gas pipeline hoisting construction. As a result, it is impossible to accurately perform stress analysis on the girth weld of the oil and gas pipeline during the hoisting construction process. Summary of the invention
[0005] The technical problem to be solved by the present invention is that it is impossible to accurately perform stress analysis on the girth weld of the oil and gas pipeline during the hoisting construction process.
[0006] In order to solve the above technical problems, the present invention provides a stress analysis method for girth welds in oil and gas pipeline hoisting construction, which specifically adopts the following technical solutions:
[0007] The present invention provides a stress analysis method for girth welds in oil and gas pipeline hoisting construction, comprising: first, obtaining pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters of the oil and gas pipeline to be hoisted. Then, according to the pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters, determine the stress condition of the oil and gas pipeline to be hoisted during the hoisting construction process, and determine the first position, which is the pipeline position corresponding to the maximum stress of the oil and gas pipeline to be hoisted during the hoisting construction process. Secondly, extract the internal force and internal moment of the truncation position, which is the pipeline position after the girth weld is pre-set at the first position and truncated. Next, construct a three-dimensional girth weld entity model according to the geometric parameters, model parameters and performance parameters of the girth weld, and apply the internal force and internal moment of the truncation position as boundary loads to the three-dimensional girth weld entity model to obtain the three-dimensional girth weld entity model after the boundary load is applied. Finally, according to the three-dimensional girth weld entity model after the boundary load is applied, determine the stress and deformation of the oil and gas pipeline to be hoisted, as well as the stress and deformation of the girth weld.
[0008] This method combines pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters to construct a three-dimensional girth weld entity model, and combines the three-dimensional girth weld entity model to simulate and analyze the oil and gas pipeline to be hoisted during the hoisting construction process to determine the stress and deformation of the oil and gas pipeline to be hoisted, as well as the stress and deformation of the girth weld. In this way, this method can effectively analyze the construction stress of the girth weld during the hoisting construction of the oil and gas pipeline, and improve the accuracy of stress analysis of the girth weld of the oil and gas pipeline during the hoisting construction, thereby preventing damage to the girth weld of the oil and gas pipeline during the construction process.
[0009] In an optional implementation, the above-mentioned method determines the stress conditions of the oil and gas pipeline to be hoisted during the hoisting construction process according to the pipeline specification parameters, the trench specification parameters and the pipeline hoisting process parameters, and determines the first position, specifically including: first, a finite element model is established according to the pipeline specification parameters, the trench specification parameters and the pipeline hoisting process parameters; wherein the finite element model is used to simulate the hoisting construction process of the oil and gas pipeline to be hoisted, and the trench and the ground in the finite element model are simulated by a rigid body, and the oil and gas pipeline to be hoisted is in contact with the trench and the ground. Then, according to the finite element model, the hoisting construction process of the oil and gas pipeline to be hoisted is simulated and analyzed to determine the stress conditions of the oil and gas pipeline to be hoisted during the hoisting construction process. Finally, according to the stress conditions of the oil and gas pipeline to be hoisted during the hoisting construction process, the stress distribution of the oil and gas pipeline to be hoisted is extracted to determine the first position.
[0010] In this implementation, the first position can be accurately and effectively determined through the finite element model, which can further improve the accuracy of stress analysis of the girth weld of the oil and gas pipeline during the lifting construction process.
[0011] In an optional implementation, the above-mentioned three-dimensional girth weld solid model after applying boundary load is used to determine the stress and deformation of the oil and gas pipeline to be hoisted, as well as the stress and deformation of the girth weld, including: calculating the stress and deformation of the oil and gas pipeline to be hoisted, as well as the stress and deformation of the girth weld according to the finite element model through the three-dimensional girth weld solid model after applying boundary load.
[0012] In an optional implementation, the stress and deformation conditions of the oil and gas pipeline to be hoisted, and the stress and deformation conditions of the girth weld include: the maximum stress position and stress value distribution corresponding to the pipe body, weld, and hot zone of the oil and gas pipeline to be hoisted.
[0013] In an optional implementation, the above pipeline specification parameters include one or more of the following parameters: steel grade, wall thickness, pipeline straight pipe parameters, pipeline bending parameters, lengths of each section of the pipeline, and angles of pipeline bends.
[0014] In an optional implementation, the trench specification parameters include one or more of the following parameters: depth, width, slope ratio, trench edge safety distance, and trench soil type.
[0015] In an optional implementation, the above-mentioned pipeline lifting process parameters include one or more of the following parameters: the number of pipe hangers, the specifications of the pipe hangers, the positions of the lifting points, the spacing between the pipe hangers, the distance between the pipe hangers and the ditch edge, and the lifting height of the pipe hangers.
[0016] In an optional implementation, the geometric parameters of the above-mentioned girth weld include one or more of the following parameters: pipe diameter, wall thickness, slope angle, blunt edge, turn height, and joint gap.
[0017] In an optional implementation, the model parameters of the above-mentioned girth weld include one or more of the following parameters: root weld excess width, root weld excess height, weld cap excess width, and hot zone width.
[0018] In an optional implementation, the performance parameters of the girth weld include: material constitutive curves corresponding to the pipe body, girth weld, and hot zone of the oil and gas pipeline to be hoisted. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 A schematic diagram of the principle of the girth weld stress analysis method for oil and gas pipeline hoisting construction provided in an embodiment of the present application;
[0020] Figure 2 A schematic diagram of a process flow of a girth weld stress analysis method for oil and gas pipeline hoisting construction provided in an embodiment of the present application;
[0021] Figure 3 A schematic diagram of a finite element model provided in an embodiment of the present application;
[0022] Figure 4 A schematic structural diagram of a three-dimensional girth weld solid model provided in an embodiment of the present application. DETAILED DESCRIPTION
[0023] The following embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following embodiments do not represent all implementations consistent with the present application. They are only examples of systems and methods consistent with some aspects of the present application as detailed in the claims.
[0024] With the large-scale construction of high-pressure, large-diameter, and high-grade steel pipelines, higher requirements and huge challenges have been brought to the inherent safety of pipeline operation. Therefore, it is necessary to strengthen the safety verification of the oil and gas pipeline construction process from the construction period to fundamentally ensure the quality of the oil and gas pipeline project. During the construction of buried oil and gas pipelines, an important part is the lifting and trenching operation of the oil and gas pipelines.
[0025] The oil and gas pipeline will be subjected to bending and axial stress during the process of hoisting and trenching. Under unreasonable hoisting stress, the pipeline weld and parent material will undergo plastic deformation. In particular, the weld will have the possibility of forming cracks under low-temperature hoisting stress, and even cause the oil and gas pipeline to break.
[0026] At present, relevant technologies have conducted relevant research on the influence of pipeline stress during the hoisting construction process. For example, the main influencing factors of the oil and gas pipeline trenching process and the influence of the oil and gas pipeline trenching process on pipeline stress have been studied and analyzed, and a prediction method for the hoisting trenching process has been formed. However, the influence of the key parameters of the hoisting trenching on the cracking of the girth weld cannot be determined, resulting in insufficient support for stress control of the oil and gas pipeline hoisting construction. As a result, it is impossible to accurately perform stress analysis on the girth weld of the oil and gas pipeline during the hoisting construction process.
[0027] In order to solve the above problems, the present application provides a method for analyzing the stress of the girth weld during the hoisting construction of oil and gas pipelines. Figure 1 The schematic diagram of the principle of the stress analysis method of the girth weld of the oil and gas pipeline hoisting construction provided in the embodiment of the present application. Figure 1 As shown, first, determine the pipeline position corresponding to the maximum stress of the oil and gas pipeline 100 to be hoisted. Then, pre-set the girth weld 101 at the pipeline position corresponding to the maximum stress and cut it off. Next, extract the internal force and internal moment at the cut-off position 102, that is, Figure 1M1, M2, F1, and F2 in . Further, the internal force and internal moment at the truncation position are applied to the three-dimensional girth weld solid model 103 as boundary loads. Finally, the stress and deformation of the oil and gas pipeline to be hoisted, as well as the stress and deformation of the girth weld, are determined based on the three-dimensional girth weld solid model 103 after the boundary load is applied. In this way, the method can effectively analyze the construction stress of the girth weld during the hoisting construction of the oil and gas pipeline, and improve the accuracy of the stress analysis of the girth weld of the oil and gas pipeline during the hoisting construction, thereby preventing the girth weld of the oil and gas pipeline from being damaged during the construction process.
[0028] The solution provided by the embodiment of the present application is introduced below in conjunction with the accompanying drawings.
[0029] For details, see Figure 2 , is a flow chart of a stress analysis method for a girth weld during oil and gas pipeline hoisting construction provided in an embodiment of the present application, such as Figure 2 As shown, the method for analyzing the stress of the girth weld during the hoisting construction of the oil and gas pipeline provided by the present invention comprises the following steps S101-S105:
[0030] S101. Obtain pipeline specification parameters, trench specification parameters, and pipeline hoisting process parameters of the oil and gas pipeline to be hoisted.
[0031] In some embodiments, obtaining the pipeline specification parameters of the oil and gas pipeline to be hoisted may specifically include one or more of the following parameters: steel grade, wall thickness, pipeline straight pipe parameters, pipeline bend parameters, length of each section of the pipeline, and angle of the pipeline bend.
[0032] In some embodiments, obtaining the specification parameters of the trench for the oil and gas pipeline to be hoisted includes one or more of the following parameters: depth, width, slope ratio, trench edge safety distance, and trench soil type.
[0033] In some embodiments, obtaining the pipeline lifting process parameters of the oil and gas pipeline to be lifted includes one or more of the following parameters: the number of pipe lifters, the specifications of the pipe lifters, the positions of the lifting points, the spacing between the pipe lifters, the distance between the pipe lifters and the ditch edge, and the lifting height of the pipe lifters.
[0034] S102. Determine the stress condition of the oil and gas pipeline to be hoisted during the hoisting construction process according to the pipeline specification parameters, the trench specification parameters and the pipeline hoisting process parameters, and determine the first position.
[0035] Among them, the first position is the pipeline position corresponding to the maximum stress of the oil and gas pipeline to be hoisted during the hoisting construction process.
[0036] Specifically, the first position can be determined by a finite element model, that is, the finite element model can be used to determine the first position by calculation according to pipeline specification parameters, trench specification parameters, and pipeline hoisting process parameters.
[0037] In some embodiments, S102 may specifically include the following steps S1021-S1023:
[0038] S1021. Establish a finite element model based on pipeline specification parameters, trench specification parameters and pipeline lifting process parameters.
[0039] Among them, the finite element model is used to simulate the hoisting construction process of the oil and gas pipeline to be hoisted. In the finite element model, the trench and the ground are simulated by rigid bodies, and the oil and gas pipeline to be hoisted is in contact with the trench and the ground.
[0040] In one implementation, the finite element model can be obtained by three-dimensional modeling. Figure 3 A schematic diagram of a finite element model provided in an embodiment of the present application, such as Figure 3 As shown, h is the height of the oil and gas pipeline 300 to be hoisted from the ground, f is the force of the oil and gas pipeline 300 to be hoisted in the vertical direction, L is the spacing between the lifting points (i.e., the spacing between the pipelayers), and b is the depth of the trench.
[0041] S1022. Perform simulation analysis on the lifting construction process of the oil and gas pipeline to be lifted based on the finite element model to determine the stress conditions of the oil and gas pipeline to be lifted during the lifting construction process.
[0042] For example, the simulation analysis of the lifting construction process of the oil and gas pipeline to be lifted is reversed in three steps: first, the oil and gas pipeline to be lifted is placed in the bottom of the trench as a whole and gravity is applied. Then, a lifting load is applied to the midpoint of the oil and gas pipeline to be lifted, and the oil and gas pipeline to be lifted is lifted to a preset lifting height. Finally, the oil and gas pipeline to be lifted placed on the ground is lifted to the ground height.
[0043] S1023. Extract the stress distribution of the oil and gas pipeline to be hoisted according to the stress conditions of the oil and gas pipeline to be hoisted during the hoisting construction process, and determine the first position.
[0044] Finally, according to S1022, the simulation analysis of the oil and gas pipeline to be hoisted during the hoisting construction process is performed to obtain the stress analysis simulation result, that is, the stress condition. The stress distribution of the oil and gas pipeline to be hoisted is extracted according to the stress analysis simulation result. Further, the first position can be determined according to the stress distribution.
[0045] S103, extracting the internal force and internal moment at the truncation position, where the truncation position is the position of the pipeline after the girth weld is preset at the first position and truncation.
[0046] Specifically, according to the first position determined in S102, the girth weld may be preset at the first position and the oil and gas pipeline to be hoisted may be cut off, and the internal force and internal moment at the cut-off position may be extracted at the same time.
[0047] S104, constructing a three-dimensional girth weld solid model according to the geometric parameters, model parameters and performance parameters of the girth weld, and applying the internal force and internal moment at the truncation position as boundary loads to the three-dimensional girth weld solid model to obtain the three-dimensional girth weld solid model after the boundary loads are applied.
[0048] Specifically, firstly, a three-dimensional girth weld solid model can be constructed according to the geometric parameters, model parameters and performance parameters of the girth weld.
[0049] In some embodiments, the geometric parameters of the girth weld include one or more of the following parameters: pipe diameter, wall thickness, slope angle, blunt edge, turn height, and joint gap.
[0050] The model parameters of the girth weld include one or more of the following parameters: root weld excess width, root weld excess height, weld cap excess width, and hot zone width.
[0051] The performance parameters of the girth weld include: the material constitutive curves corresponding to the pipe body, girth weld and hot zone of the oil and gas pipeline to be hoisted.
[0052] Among them, the hot zone is the heat-affected zone formed on both sides of the weld due to welding. During the welding process, high temperature will cause the structural changes of the pipeline material of the oil and gas pipeline to be hoisted, resulting in lateral diffusion and distortion. The formed area is called the heat-affected zone, also known as the hot zone.
[0053] In the embodiment of the present application, the geometric parameters, model parameters and performance parameters of the above-mentioned girth weld may be obtained in advance, and the hot zone may be preset.
[0054] Furthermore, the girth weld load is introduced into the constructed three-dimensional girth weld solid model. Specifically, the internal force and internal moment at the truncation position are applied to the three-dimensional girth weld solid model as boundary loads to obtain the three-dimensional girth weld solid model after the boundary loads are applied.
[0055] S105. Determine the stress and deformation of the oil and gas pipeline to be hoisted and the stress and deformation of the girth weld according to the three-dimensional girth weld solid model after the boundary load is applied.
[0056] In some embodiments, S105 may specifically include: based on the finite element model, by applying boundary loads to the three-dimensional girth weld solid model, the stress and deformation of the oil and gas pipeline to be hoisted and the stress and deformation of the girth weld may be calculated.
[0057] In some embodiments, the stress and deformation conditions of the oil and gas pipeline to be hoisted, and the stress and deformation conditions of the girth weld may specifically include: the maximum stress position and stress value distribution corresponding to the pipe body, weld, and hot zone of the oil and gas pipeline to be hoisted.
[0058] The girth weld stress analysis method for oil and gas pipeline hoisting construction provided in the embodiment of the present application is adopted, and the pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters are combined to construct a three-dimensional girth weld entity model, and the three-dimensional girth weld entity model is combined to simulate and analyze the oil and gas pipeline to be hoisted during the hoisting construction process to determine the stress and deformation of the oil and gas pipeline to be hoisted, as well as the stress and deformation of the girth weld. In this way, the method can effectively analyze the construction stress of the girth weld during the hoisting construction of the oil and gas pipeline, and improve the accuracy of the stress analysis of the girth weld of the oil and gas pipeline during the hoisting construction, thereby preventing the girth weld of the oil and gas pipeline from being damaged during the construction process.
[0059] In some embodiments, a method for analyzing the stress of a girth weld during the lifting construction of an oil and gas pipeline provided in an embodiment of the present application is described with specific examples.
[0060] First, obtain the pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters of the oil and gas pipeline to be hoisted.
[0061] Specifically, taking the following parameters as an example, the pipeline specification parameters include: steel grade is X80, the diameter of the straight pipe is 1422mm, and the wall thickness is 21.4mm. The pipe trench specification parameters include: depth is 2m, width is 3m, slope ratio is 0.75, and the safety distance from the trench is 1m. The pipeline hoisting process parameters are: 7 90t pipe hoists are used for hoisting. The specific pipeline hoisting process parameters are shown in Table 1 below. Among them, hoisting point 1 is the outermost hoisting point on the trench, and hoisting point 7 is the hoisting point under the trench close to the bottom of the trench.
[0062] Table 1 Pipeline hoisting process parameters
[0063] Physical quantity Hanging point 1 Hanging point 2 Hanging point 3 Hanging point 4 Hanging point 5 Hanging point 6 Hanging point 7 Horizontal force (t) -0.80 -1.10 -1.22 1.22 1.10 1.00 0.80 Vertical force(t) 26.00 25.00 25.00 13.50 11.50 10.00 3.00 Horizontal displacement(m) -1.55 -2.01 -2.50 -3.00 -3.46 -3.84 -4.14 Vertical displacement(m) 0.51 0.54 0.19 -0.49 -1.33 -2.10 -2.65
[0064] Then, according to the above pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters, the stress condition of the oil and gas pipeline to be hoisted during the hoisting construction process is determined, and the first position is determined.
[0065] In this embodiment, based on the above pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters, simulation analysis is performed to obtain the stress conditions of each pipeline during the hoisting construction of the oil and gas pipeline to be hoisted, as shown in Table 2 below.
[0066] Table 2 Stress conditions of the oil and gas pipelines to be hoisted during the hoisting construction process
[0067]
[0068] As shown in Table 2, the first position is the position of the hanging point 6.
[0069] Secondly, the girth weld is preset at the truncation position (i.e., the position of the hanging point 6) and truncation, and the internal force and internal moment at the truncation position are extracted at the same time.
[0070] In this embodiment, the internal forces and internal moments at the truncation position can be extracted and imported from the above simulation results.
[0071] Furthermore, a three-dimensional girth weld solid model is constructed according to the geometric parameters, model parameters and performance parameters of the girth weld, and the internal force and internal moment at the truncation position are applied to the three-dimensional girth weld solid model as boundary loads.
[0072] Among them, the performance parameters of the girth weld, that is, the material constitutive curves corresponding to the pipe body, girth weld, and hot zone of the oil and gas pipeline to be hoisted can be obtained from the test results of the same steel grade X80 and imported into the model for calculation.
[0073] For example, Figure 4 A schematic diagram of the structure of a three-dimensional girth weld solid model provided in an embodiment of the present application, such as Figure 4 As shown, the figure includes a pipeline joint 401 and a girth weld 402 of the oil and gas pipeline to be hoisted.
[0074] Finally, the stress and deformation of the oil and gas pipeline to be hoisted and the stress and deformation of the girth weld are determined based on the three-dimensional girth weld solid model after the boundary load is applied.
[0075] Specifically, according to the simulation analysis results, the distribution of axial stress, hoop stress, MISES stress and other parts of the pipe body, weld and hot zone can be obtained, and the stress vulnerable points of the circumferential weld during the installation of the oil and gas pipeline to be hoisted can be obtained.
[0076] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.
[0077] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0078] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0079] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0080] Similar parts between the embodiments provided in this application can be referenced to each other. The specific implementation methods provided above are only a few examples under the general concept of this application and do not constitute a limitation on the protection scope of this application. For those skilled in the art, any other implementation methods expanded based on the scheme of this application without creative work belong to the protection scope of this application.
Claims
1. A stress analysis method for girth welds in oil and gas pipeline hoisting construction, characterized in that: include: Obtain the pipeline specification parameters, trench specification parameters and pipeline hoisting process parameters of the oil and gas pipeline to be hoisted; Determine the stress condition of the oil and gas pipeline to be hoisted during the hoisting construction process according to the pipeline specification parameters, the trench specification parameters and the pipeline hoisting process parameters, and determine a first position, where the first position is the pipeline position corresponding to the maximum stress of the oil and gas pipeline to be hoisted during the hoisting construction process; Extracting the internal force and internal moment of the truncation position, wherein the truncation position is the position of the pipeline after the girth weld is pre-set at the first position and truncation; Constructing a three-dimensional girth weld solid model according to the geometric parameters, model parameters and performance parameters of the girth weld, and applying the internal force and internal moment at the truncation position as boundary loads to the three-dimensional girth weld solid model to obtain a three-dimensional girth weld solid model after applying the boundary loads; The stress and deformation of the oil and gas pipeline to be hoisted and the stress and deformation of the girth weld are determined based on the three-dimensional girth weld solid model after the boundary load is applied.
2. The method according to claim 1, characterized in that The step of determining the stress condition of the oil and gas pipeline to be hoisted during the hoisting construction process according to the pipeline specification parameters, the trench specification parameters and the pipeline hoisting process parameters, and determining the first position includes: A finite element model is established according to the pipeline specification parameters, the trench specification parameters and the pipeline hoisting process parameters; wherein the finite element model is used to simulate the hoisting construction process of the oil and gas pipeline to be hoisted, the trench and the ground in the finite element model are simulated by a rigid body, and the oil and gas pipeline to be hoisted is in contact with the trench and the ground; Performing simulation analysis on the oil and gas pipeline to be hoisted during the hoisting construction process according to the finite element model to determine the stress condition of the oil and gas pipeline to be hoisted during the hoisting construction process; The stress distribution of the oil and gas pipeline to be hoisted is extracted according to the stress conditions of the oil and gas pipeline to be hoisted during the hoisting construction process, and the first position is determined.
3. The method according to claim 2, characterized in that Determining the stress and deformation of the oil and gas pipeline to be hoisted and the stress and deformation of the girth weld according to the three-dimensional girth weld entity model after applying the boundary load includes: The stress and deformation of the oil and gas pipeline to be hoisted and the stress and deformation of the girth weld are calculated based on the finite element model through the three-dimensional girth weld solid model after the boundary load is applied.
4. The method according to claim 3, characterized in that The stress and deformation conditions of the oil and gas pipeline to be hoisted, and the stress and deformation conditions of the girth weld include: the maximum stress positions and stress value distributions corresponding to the pipe body, weld, and hot zone of the oil and gas pipeline to be hoisted, respectively.
5. The method according to claim 1, characterized in that The pipeline specification parameters include one or more of the following parameters: steel grade, wall thickness, pipeline straight pipe parameters, pipeline bending parameters, lengths of each section of the pipeline, and angles of pipeline bending.
6. The method according to claim 1, characterized in that The trench specification parameters include one or more of the following parameters: depth, width, slope ratio, trench side safety distance, and trench soil type.
7. The method according to claim 1, characterized in that The pipeline lifting process parameters include one or more of the following parameters: the number of pipe lifters, specifications of pipe lifters, lifting point positions, spacing between pipe lifters, distance between pipe lifters and ditch edge, and lifting height of pipe lifters.
8. The method according to claim 1, characterized in that The geometric parameters of the girth weld include one or more of the following parameters: pipe diameter, wall thickness, slope angle, blunt edge, turn height, and joint gap.
9. The method according to claim 1, characterized in that: The model parameters of the girth weld include one or more of the following parameters: root weld excess width, root weld excess height, weld cap excess width, and hot zone width.
10. The method according to claim 1, characterized in that The performance parameters of the girth weld include: the material constitutive curves corresponding to the pipe body of the oil and gas pipeline to be hoisted, the girth weld, and the hot zone respectively.