Method and device for calculating pipeline circumferential weld fracture damage

Abstract

The invention relates to the technical field of pipeline damage calculation, in particular to a pipeline circumferential weld fracture damage calculation method and device.The method comprises the steps that a material point corresponding to a target pipeline circumferential weld is obtained, and a key constant is calculated; calculating the single key force of different substance point keys by using the key constant, and calculating the total key force of all substance points according to the single key force; according to motion influence information generated by the total key force on the substance points, the stretching rates of the keys of the different substance points are determined; calculating a critical elongation rate based on the material information of the circumferential weld of the target pipeline; and calculating the damage value of the circumferential weld of the target pipeline based on the stretching rate and the critical stretching rate of the key. Therefore, the problems that in the related technology, the singularity of the crack tip cannot be effectively solved, and particularly, the dynamic behavior of the crack tip is difficult to accurately capture in the high-speed crack propagation process, so that certain limitation exists in the process of predicting the circumferential weld cracking behavior; the influence of the material characteristics of different areas on crack propagation under the actual working condition cannot be comprehensively reflected.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline damage calculation, and in particular to a method and device for calculating pipeline girth weld fracture damage. Background Art

[0002] The acceleration of urbanization and the continuous growth of energy demand have made high-grade steel, large-diameter, and high-pressure transmission the inevitable choice for natural gas pipeline projects. Some major national pipeline projects have gradually adopted X80 as the preferred steel grade for trunk pipelines. However, with the increase in the number of X80 steel grade pipelines and the rapid development of natural gas hydrogen blending technology, the risk of girth weld cracking has increased significantly and has become the main factor in pipeline failure.

[0003] In related technologies, the GTN model can be used to describe the ductile fracture process of materials. From a microscopic perspective, the plastic deformation and damage of materials under stress are linked to the nucleation, growth, and aggregation behaviors of micropores at the microscopic level. The deformation and damage process of materials under the macroscopic state can be simulated by controlling the evolution of micropores. It can also be achieved by establishing a peridynamics-finite element coupling model, applying load boundary conditions, and using user-defined subroutines to perform calculations to predict the ultimate strain capacity of high-grade steel pipeline girth welds.

[0004] However, in the related technologies, when solving discontinuity problems such as crack propagation, the singularity of the crack tip cannot be effectively resolved. Especially during high-speed crack propagation, it is difficult to accurately capture the dynamic behavior of the crack tip. The mesh distortion and singularity assumptions may lead to numerical instability, resulting in certain limitations in predicting the cracking behavior of circumferential welds. It fails to fully reflect the impact of material properties in different regions on crack propagation under actual working conditions, and urgently needs improvement. Summary of the invention

[0005] The present invention provides a method and device for calculating the fracture damage of a pipeline girth weld, so as to solve the problems in the related art that the singularity of the crack tip cannot be effectively solved, especially in the process of high-speed crack propagation, it is difficult to accurately capture the dynamic behavior of the crack tip, resulting in certain limitations in predicting the cracking behavior of the girth weld, and failing to fully reflect the influence of material properties in different regions on crack propagation under actual working conditions.

[0006] A first aspect of the present invention provides a method for calculating the fracture damage of a pipeline girth weld, comprising the following steps: obtaining at least one material point corresponding to a target pipeline girth weld, and calculating the bond constant between different material points; using the bond constant to calculate the single bond force of the bonds of different material points, and calculating the total bond force of all material points based on the single bond force; determining the stretch rate of the bonds of different material points based on the motion influence information generated by the total bond force on the at least one material point; based on the material information of the target pipeline girth weld, calculating the critical stretch rate corresponding to the bonds of different material points; and calculating the damage value of the target pipeline girth weld based on the stretch rate of the bond and the critical stretch rate.

[0007] Optionally, in one embodiment of the present invention, obtaining at least one material point corresponding to the target pipeline girth weld includes: simplifying the target pipeline girth weld into a target two-dimensional tetrahedral model having at least one of a base material zone, a heat-affected zone and a weld zone; performing material point discretization processing on the target two-dimensional tetrahedral model to obtain base material points located in the base material zone, heat-affected material points located in the heat-affected zone and weld material points located in the weld zone in the near field; and obtaining the at least one material point based on the base material points, the heat-affected material points and the weld material points.

[0008] Optionally, in one embodiment of the present invention, the calculating the bond constant between different material points includes: when the different material points are located in the same area, using a first bond constant calculation formula to calculate the bond constant; when the different material points are located in different areas, using a second bond constant calculation formula to calculate the bond constant.

[0009] Optionally, in one embodiment of the present invention, The expression of the first bond constant calculation formula may be, but is not limited to,: , in, is the bond constant, E is the elastic modulus of the corresponding area, is the distance between material points, is the radius of the near field; The expression of the second bond constant calculation formula may be, but is not limited to,: , in, is the elastic modulus of the current material point, is the elastic modulus of the material point of the family domain member, is the distance between material points, is the radius of the near field.

[0010] Optionally, in one embodiment of the present invention, the damage value of the target pipe girth weld is calculated based on the stretch rate of the key and the critical stretch rate, including: judging whether the stretch rate of the key is greater than the critical stretch rate; if the stretch rate of the key is greater than the critical stretch rate, judging that the corresponding key is broken, and counting the first number of all broken keys; if the stretch rate of the key is less than or equal to the critical stretch rate, judging that the corresponding key is not broken, and counting the second number of all non-broken keys; and calculating the damage value based on the first number and the second number.

[0011] Optionally, in one embodiment of the present invention, calculating the critical stretching rate corresponding to the different material point keys includes: when the different material points are located in the same area, using a first critical stretching rate calculation formula to calculate the critical stretching rate; when the different material points are located in different areas, using a second critical stretching rate calculation formula to calculate the critical stretching rate.

[0012] Optionally, in one embodiment of the present invention, The first critical elongation calculation formula may be, but is not limited to,: , in, is the tensile strength of the material, is the elastic modulus; The second critical elongation calculation formula may be, but is not limited to,: , in, and are the elastic modulus and critical stretch rate of the current material point, and are the elastic modulus and critical elongation of the domain members, respectively.

[0013] Optionally, in one embodiment of the present invention, the calculation formula of the damage value may be but is not limited to: , in, Describe the extent of the injury, represents the number of unbroken bonds of a material point in the near field, Indicates the total number of keys, Represents a key state function.

[0014] The second aspect of the present invention provides a device for calculating the fracture damage of a pipeline girth weld, including: a first calculation module, used to obtain at least one material point corresponding to the target pipeline girth weld, and calculate the bond constant between different material points; a second calculation module, used to calculate the single bond force of the bonds of different material points using the bond constant, and calculate the total bond force of all material points based on the single bond force; a determination module, used to determine the stretch rate of the bonds of different material points based on the motion influence information generated by the total bond force on the at least one material point; a third calculation module, used to calculate the critical stretch rate corresponding to the bonds of different material points based on the material information of the target pipeline girth weld; a fourth calculation module, used to calculate the damage value of the target pipeline girth weld based on the stretch rate of the bond and the critical stretch rate.

[0015] Optionally, in one embodiment of the present invention, the first calculation module includes: a simplification unit, used to simplify the target pipeline girth weld into a target two-dimensional tetrahedral model having at least one of a base material zone, a heat-affected zone and a weld zone; a discrete unit, used to perform material point discretization processing on the target two-dimensional tetrahedral model to obtain base material points located in the base material zone, heat-affected material points located in the heat-affected zone and weld material points located in the weld zone in the near field; and a generation unit, used to obtain the at least one material point based on the base material points, the heat-affected material points and the weld material points.

[0016] Optionally, in one embodiment of the present invention, the first calculation module includes: a first calculation unit, used to calculate the bond constant using a first bond constant calculation formula when the different material points are located in the same area; and a second calculation unit, used to calculate the bond constant using a second bond constant calculation formula when the different material points are located in different areas.

[0017] Optionally, in one embodiment of the present invention, The expression of the first bond constant calculation formula may be, but is not limited to,: , in, is the bond constant, E is the elastic modulus of the corresponding area, is the distance between material points, is the radius of the near field; The expression of the second bond constant calculation formula may be, but is not limited to,: , in, is the elastic modulus of the current material point, is the elastic modulus of the material point of the family domain member, is the distance between material points, is the radius of the near field.

[0018] Optionally, in one embodiment of the present invention, the fourth calculation module includes: a judgment unit, used to judge whether the stretch rate of the key is greater than the critical stretch rate; a first statistical unit, used to judge that the corresponding key is broken when the stretch rate of the key is greater than the critical stretch rate, and count the first number of all broken keys; a second statistical unit, used to judge that the corresponding key is not broken when the stretch rate of the key is less than or equal to the critical stretch rate, and count the second number of all non-broken keys; a third calculation unit, used to calculate the damage value based on the first number and the second number.

[0019] Optionally, in one embodiment of the present invention, the third calculation module includes: a fourth calculation unit, used to calculate the critical stretch rate using the first critical stretch rate calculation formula when the different material points are located in the same area; and a fifth calculation unit, used to calculate the critical stretch rate using the second critical stretch rate calculation formula when the different material points are located in different areas.

[0020] Optionally, in one embodiment of the present invention, The first critical elongation calculation formula may be, but is not limited to,: , in, is the tensile strength of the material, is the elastic modulus; The second critical elongation calculation formula may be, but is not limited to,: , in, and are the elastic modulus and critical stretch rate of the current material point, and are the elastic modulus and critical elongation of the domain members, respectively.

[0021] Optionally, in one embodiment of the present invention, the calculation formula of the damage value may be but is not limited to: , in, Describe the extent of the injury, represents the number of unbroken bonds of a material point in the near field, Indicates the total number of keys, Represents a key state function.

[0022] A third aspect of the present invention provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for calculating the fracture damage of a pipeline girth weld as described in the above embodiment.

[0023] A fourth aspect of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned method for calculating the fracture damage of a pipeline girth weld.

[0024] A fifth aspect of the present invention provides a computer program product, including a computer program, which, when executed, implements the above-mentioned method for calculating the fracture damage of the pipeline girth weld.

[0025] The embodiment of the present invention can calculate the bond constant of the material point obtained by simplifying the girth weld of the target pipeline, and then calculate the single bond force and the total bond force, and determine the stretch rate of the bonds of different material points based on the motion influence information of the total bond force on the material point, and calculate the damage value of the girth weld of the target pipeline based on the stretch rate of the bond and the corresponding critical stretch rate. By considering the geometric structure of the weld area and the material performance characteristics, a near-field dynamics method is used to construct a numerical model suitable for the fracture failure of the girth weld of the target pipeline, which can accurately simulate the brittle fracture process caused by the dynamic expansion of the crack, and fully consider the influence of the parent material area, the weld area and the heat-affected zone, providing an efficient and reliable analysis tool for pipeline safety assessment and life prediction. Therefore, the problem that the singularity of the crack tip cannot be effectively solved in the related technology, especially in the process of high-speed crack expansion, it is difficult to accurately capture the dynamic behavior of the crack tip, resulting in certain limitations in predicting the cracking behavior of the girth weld, and failing to fully reflect the influence of material properties in different regions on crack expansion under actual working conditions.

[0026] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 A flow chart of a method for calculating pipeline girth weld fracture damage according to an embodiment of the present invention; Figure 2 A simplified block diagram of a pipeline structure provided according to an embodiment of the present invention; Figure 3 A block diagram of area division according to an embodiment of the present invention; Figure 4A schematic diagram of a storage and index array provided according to an embodiment of the present invention; Figure 5 A schematic diagram of material points in the same region and in different regions constituting bonds according to an embodiment of the present invention; Figure 6 A schematic diagram of truncating the peridynamic force across the crack surface provided according to an embodiment of the present invention; Figure 7 A flow chart showing the working principle of a method for calculating pipeline girth weld fracture damage according to an embodiment of the present invention; Figure 8 A schematic block diagram of a device for calculating pipeline girth weld fracture damage according to an embodiment of the present invention; Fig. 9 It is a schematic diagram of the structure of an electronic device provided according to an embodiment of the present invention.

[0028] Reference numerals: Among them, 201-parent material area, 202-heat affected zone, 203-weld area; 10-calculation device for pipeline girth weld fracture damage; 100-first calculation module, 200-second calculation module, 300-determination module, 400-third calculation module, 500-fourth calculation module; 901-memory, 902-processor, 903-communication interface. DETAILED DESCRIPTION

[0029] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0030] The following describes a method and device for calculating pipeline girth weld fracture damage according to an embodiment of the present invention with reference to the accompanying drawings. In view of the fact that the singularity of the crack tip cannot be effectively solved as mentioned in the above background technology, especially in the process of high-speed crack propagation, it is difficult to accurately capture the dynamic behavior of the crack tip, resulting in certain limitations in predicting the cracking behavior of the girth weld, and failing to fully reflect the influence of material properties in different regions on crack propagation under actual working conditions. The present invention provides a method for calculating the fracture damage of a pipeline girth weld. In this method, the bond constant of a material point simplified from the girth weld of a target pipeline can be calculated, and then the single bond force and the total bond force can be calculated. According to the motion influence information of the total bond force on the material point, the elongation of the bonds of different material points is determined, and based on the elongation of the bonds and the corresponding critical elongation, the damage value of the girth weld of the target pipeline is calculated. By considering the geometric structure of the weld area and the material performance characteristics, a near-field dynamics method is adopted to construct a numerical model for the fracture failure of the girth weld of the target pipeline, which can accurately simulate the brittle fracture process caused by the dynamic propagation of the crack, and fully consider the influence of the parent material area, the weld area and the heat-affected zone, so as to provide an efficient and reliable analysis tool for pipeline safety assessment and life prediction. As a result, the problem in related technologies that the singularity of the crack tip cannot be effectively resolved, especially during high-speed crack propagation, it is difficult to accurately capture the dynamic behavior of the crack tip, resulting in certain limitations in predicting the cracking behavior of the circumferential weld and failure to fully reflect the impact of material properties in different regions on crack propagation under actual working conditions.

[0031] Specifically, Figure 1 The present invention provides a flowchart of a method for calculating pipeline girth weld fracture damage according to an embodiment of the present invention.

[0032] like Figure 1 As shown, the calculation method of the pipeline girth weld fracture damage includes the following steps: In step S101, at least one material point corresponding to the girth weld of the target pipeline is obtained, and the bond constants between different material points are calculated.

[0033] It is understandable that the embodiment of the present invention mainly calculates the fracture damage of the girth weld of high-strength steel. The girth weld is a crucial connection part in pipeline engineering, and its quality directly affects the safe and stable operation of the pipeline system. The embodiment of the present invention can determine the corresponding material point for the high-strength steel pipeline.

[0034] In some embodiments, the embodiments of the present invention can perform material point discretization based on the target pipeline girth weld, such as the high-strength steel pipeline girth weld, to obtain at least one material point, and calculate the bond constants between different material points through the corresponding calculation formula.

[0035] Optionally, in one embodiment of the present invention, obtaining at least one material point corresponding to the target pipeline girth weld includes: simplifying the target pipeline girth weld into a target two-dimensional tetrahedral model having at least one of a base material area, a heat-affected zone, and a weld area; performing material point discretization processing on the target two-dimensional tetrahedral model to obtain base material points located in the base material area, heat-affected material points located in the heat-affected zone, and weld material points located in the weld area in the near field; and obtaining at least one material point based on the base material points, the heat-affected material points, and the weld material points.

[0036] As a possible implementation method, the embodiment of the present invention can approximate the target pipeline to a plane stress state according to the structural characteristics of the target pipeline with a large diameter and thin wall, so the target pipeline with a three-dimensional cylindrical structure is simplified into a target two-dimensional tetrahedron model, as shown in the schematic diagram. Figure 2 As shown, the length direction is the axial direction of the pipeline, and the width direction is the direction of the pipeline wall thickness. The model may include, but is not limited to, a parent material area 201, a heat-affected zone 202, a weld area 203, etc., and the present invention does not impose specific restrictions. Among them, the parent material area 201 can represent the X80 steel grade of the target pipeline main body material, which is distributed on both sides of the weld; the weld area 203 can represent the area filled with welding materials, which is usually located in the center of the model; the heat-affected zone 202 can represent the area between the weld area 203 and the parent material area 201 where the material properties change due to the influence of welding heating, and the width is generally determined according to experiments.

[0037] Furthermore, the embodiment of the present invention can discretize the material points of the target two-dimensional tetrahedron model, and then obtain the parent material points located in the parent material area 201, the heat-affected material points located in the heat-affected zone 202, and the weld material points located in the weld area 203 in the near field. Figure 3 shown.

[0038] In addition, it should be noted that the embodiment of the present invention can determine the family domain members within the near field range of each material point and store their relationships in a correlation array. Figure 4 As shown. Figure 4 In the formula, i is the number of the material point, numfam is the number of family members, pointfam is the starting number of the material point family members in the family group, and nodefam is the material point family group number.

[0039] Optionally, in one embodiment of the present invention, calculating the bond constant between different material points includes: when the different material points are located in the same area, using a first bond constant calculation formula to calculate the bond constant; when the different material points are located in different areas, using a second bond constant calculation formula to calculate the bond constant. The expression of the first bond constant calculation formula may be, but is not limited to,: , in, is the bond constant, E is the elastic modulus of the corresponding area, is the distance between material points, is the radius of the near field.

[0040] The expression of the second bond constant calculation formula can be, but is not limited to,: , in, is the elastic modulus of the current material point, is the elastic modulus of the material point of the family domain member, is the distance between material points, is the radius of the near field.

[0041] It is understandable that in the embodiment of the present invention, the bond constant can be used to describe the parameter of the interaction strength between two material points. Since the weld zone, heat-affected zone and parent material zone have different material properties, the difference in bond constants can accurately reflect the mechanical differences in these zones. By calculating the bond constants in different zones, the propagation path of cracks in different material zones can be better simulated. Figure 5 As shown, the embodiment of the present invention provides a bond composed of material points in the same region and in different regions, wherein: and The bond between is the bond between the heat-affected zone 202 and the weld zone 203, which is a cross-region bond; and The keys between are keys of the same weld zone 203 and belong to the same area.

[0042] In some embodiments, when calculating the bond constants between different material points, the embodiment of the present invention can first obtain the crack information of the target pipeline girth weld, and its schematic diagram can be as follows: Figure 6 As shown, initial cracks are set along angles of 0°, 15°, 30°, 45°, 60°, 75°, and 90°.

[0043] Furthermore, in the embodiment of the present invention, when the material points are located in the same area, the calculation formula of the bond constant is the first bond constant calculation formula, and its expression can be but is not limited to: , in, is the bond constant, E is the elastic modulus of the corresponding area, is the distance between material points, is the radius of the near field.

[0044] When the material points are located in different regions, the calculation formula of the bond constant is the second bond constant calculation formula, and its expression can be but is not limited to: , in, is the elastic modulus of the current material point, is the elastic modulus of the material point of the family domain member, is the distance between material points, is the radius of the near field.

[0045] Furthermore, in the embodiment of the present invention, when the material point and its neighborhood members are in different areas (for example, the weld area and the heat-affected zone), in order to better describe the interaction between two different materials, the average value of the elastic modulus of the two materials can be used, thereby better reflecting the mechanical transition between different materials and more accurately simulating the cracking behavior.

[0046] In step S102, the single bond forces of the bonds at different material points are calculated using the bond constants, and the total bond forces of all material points are calculated based on the single bond forces.

[0047] In some embodiments, when calculating the total bond force, the embodiments of the present invention first calculate the single bond force based on the bond constant, and the calculation formula can be but is not limited to: , in, represents the coordinates of the material point after deformation, represents the coordinates of the material point after deformation, represents the coordinates of the material point before deformation, represents the coordinates of the material point before deformation, represents the bond strain, i.e. the elongation of the bond. The denominator represents the bond length after deformation minus the initial length of the bond. represents the direction vector after the bond is deformed, Indicates the bond constant. When calculating the bond force, it is multiplied by the bond constant value corresponding to each bond. represents the corrected volume, Represents the surface correction factor.

[0048] Furthermore, after calculating the single bond force, the embodiment of the present invention can adopt integral summation to calculate the total bond force.

[0049] In step S103, the stretching rates of the bonds at different material points are determined according to the motion influence information of the total bond force on at least one material point.

[0050] It is understandable that the stretching rate of the bond is caused by the influence of the total bond force on the movement of the material point, which in turn causes the change in the displacement of the material point. Therefore, the embodiment of the present invention determines the stretching rate of the bond of different material points based on the information of the movement influence of the total bond force on at least one material point. The calculation formula of the bond stretching rate can be but is not limited to: , in, represents the coordinates of the material point after deformation, represents the coordinates of the material point after deformation, represents the coordinates of the material point before deformation, Represents the coordinates of the material point before deformation.

[0051] In step S104, based on the material information of the target pipeline girth weld, the critical elongation rates corresponding to different material point bonds are calculated.

[0052] It can be understood that, in the embodiment of the present invention, the critical stretching rate is related to the material information of the target pipeline girth weld. Therefore, the embodiment of the present invention can calculate the corresponding critical stretching rate according to the material information of the target pipeline girth weld.

[0053] Optionally, in one embodiment of the present invention, calculating the critical stretching rates corresponding to different material point keys includes: when the different material points are located in the same area, using a first critical stretching rate calculation formula to calculate the critical stretching rate; when the different material points are located in different areas, using a second critical stretching rate calculation formula to calculate the critical stretching rate. The first critical stretching rate calculation formula may be, but is not limited to: , in, is the tensile strength of the material, is the elastic modulus.

[0054] The second critical elongation calculation formula may be, but is not limited to,: , in, and are the elastic modulus and critical stretch rate of the current material point, and are the elastic modulus and critical elongation of the domain members, respectively.

[0055] In some embodiments, when calculating the critical stretch rate, for a material point and its neighborhood members in the same area, the critical stretch rate calculation formula is a first critical stretch rate calculation formula, and its expression may be, but is not limited to,: , in, is the tensile strength of the material, is the elastic modulus.

[0056] In some embodiments, when calculating the critical stretch rate in the embodiments of the present invention, for a material point and its neighborhood members in different regions, the calculation formula of the critical stretch rate is a second critical stretch rate calculation formula, and its expression may be but is not limited to: , in, and are the elastic modulus and critical stretch rate of the current material point, and are the elastic modulus and critical elongation of the domain members, respectively.

[0057] In order to reflect the mechanical properties of material points in different regions, the embodiment of the present invention can adopt a weighted average based on elastic modulus. The elastic modulus is a measure of the rigidity of the material. A larger elastic modulus corresponds to a larger deformation resistance. Therefore, the embodiment of the present invention plays a weighting role in the calculation of the critical elongation rate of different regions.

[0058] In step S105, the damage value of the target pipeline girth weld is calculated based on the key elongation rate and the critical elongation rate.

[0059] As a possible implementation method, the embodiment of the present invention can calculate the elongation rate of each key and compare it with the critical elongation rate corresponding to each key to determine whether the key is broken, thereby obtaining the damage value of the target pipeline girth weld.

[0060] Optionally, in one embodiment of the present invention, based on the elongation rate and critical elongation rate of the key, the damage value of the girth weld of the target pipeline is calculated, including: judging whether the elongation rate of the key is greater than the critical elongation rate; if the elongation rate of the key is greater than the critical elongation rate, judging that the corresponding key is broken, and counting the first number of all broken keys; if the elongation rate of the key is less than or equal to the critical elongation rate, judging that the corresponding key is not broken, and counting the second number of all unbroken keys; based on the first number and the second number, calculating the damage value. The calculation formula of the damage value can be, but is not limited to, as follows: , in, Describe the extent of the injury, represents the number of broken bonds of a material point in the near field, Indicates the total number of keys.

[0061] In some embodiments, if the stretch rate of a bond is greater than a critical stretch rate, the corresponding bond is determined to be broken, and the bond state function is set to 0, and then the first number of all broken bonds is counted.

[0062] In some embodiments, if the stretch rate of a bond is less than or equal to the critical stretch rate, the corresponding bond is determined to be not broken, and the bond state function is set to 1, and then the second number of all broken bonds is counted.

[0063] Furthermore, in the embodiment of the present invention, the damage value can be calculated according to the first quantity and the second quantity. The calculation formula of the damage value can be, but is not limited to,: , in, Describe the extent of the injury, represents the number of unbroken bonds of a material point in the near field, Indicates the total number of keys, Represents a key state function.

[0064] Among them, in the embodiment of the present invention, the key state function It is related to the point force between material points and the elongation between the material points. When the bond strain exceeds the critical strain, the bond will break, the direct point force of the material point disappears, and the material point is damaged. Its expression can be but is not limited to: .

[0065] The working principle of the method for calculating the fracture damage of a pipeline girth weld proposed in an embodiment of the present invention is introduced below in conjunction with a specific embodiment.

[0066] in, Figure 7 The present invention is a flowchart of the working principle of a method for calculating pipeline girth weld fracture damage according to an embodiment of the present invention.

[0067] Step S701: Obtain material information corresponding to the pipeline girth weld.

[0068] Step S702: simplifying the pipeline girth weld into a two-dimensional tetrahedron model.

[0069] Step S703: discretizing the material points of the two-dimensional tetrahedral model to obtain material points corresponding to the base material area, the heat affected zone and the weld area in the near field.

[0070] Step S704: Calculate the bond constant.

[0071] Among them, when different material points are located in the same area, the embodiment of the present invention uses the first bond constant calculation formula to calculate the bond constant; when different material points are located in different areas, the second bond constant calculation formula is used to calculate the bond constant.

[0072] Step S705: Load initial boundary conditions.

[0073] Among them, the embodiment of the present invention can load the initial boundary conditions on the pipeline girth weld to simulate the stress conditions of different material points on the pipeline girth weld.

[0074] Step S706: Calculate the total bond force.

[0075] The embodiment of the present invention can calculate the single bond force according to the bond constant, and after calculating the single bond force, use integral summation to calculate the total bond force.

[0076] Step S707: Calculate the stretching ratio of the key.

[0077] Among them, the embodiment of the present invention can determine the stretching rate of the bonds of different material points based on the motion influence information of the total bond force on at least one material point.

[0078] Step S708: Calculate the critical stretching rate.

[0079] Among them, the embodiment of the present invention can use the first critical stretch rate calculation formula to calculate the critical stretch rate when different material points are located in the same area; when different material points are located in different areas, the second critical stretch rate calculation formula can be used to calculate the critical stretch rate.

[0080] Step S709: Determine whether the stretching rate of the key is greater than the critical stretching rate.

[0081] In this embodiment of the present invention, if the stretching rate of the key is greater than the critical stretching rate, step S710 is executed, otherwise, step S711 is executed.

[0082] Step S710: The bond is broken.

[0083] Step S711: The bond is not broken.

[0084] In this embodiment of the present invention, when the bond is not broken, the initial boundary conditions can be reloaded.

[0085] Step S712: Calculate the damage value.

[0086] Among them, the embodiment of the present invention can calculate the damage value of the pipeline girth weld according to the number of broken keys.

[0087] According to the calculation method of pipeline girth weld fracture damage proposed in the embodiment of the present invention, the bond constant of the material point obtained by simplifying the target pipeline girth weld can be calculated, and then the single bond force and the total bond force can be calculated, and the stretching rate of the bonds of different material points can be determined according to the motion influence information of the total bond force on the material point, and the damage value of the target pipeline girth weld can be calculated based on the stretching rate of the bond and the corresponding critical stretching rate. By considering the geometric structure of the weld area and the material performance characteristics, a near-field dynamics method is used to construct a numerical model suitable for the fracture failure of the target pipeline girth weld, which can accurately simulate the brittle fracture process caused by the dynamic expansion of the crack, and fully consider the influence of the parent material area, the weld area and the heat-affected zone, so as to provide an efficient and reliable analysis tool for pipeline safety assessment and life prediction. Therefore, the problems in the related technology that the singularity of the crack tip cannot be effectively solved, especially in the process of high-speed crack expansion, it is difficult to accurately capture the dynamic behavior of the crack tip, resulting in certain limitations in predicting the cracking behavior of the girth weld, and the failure to fully reflect the influence of material properties in different regions on crack expansion under actual working conditions.

[0088] Next, a device for calculating the fracture damage of a pipeline girth weld according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0089] Figure 8 The present invention is a block diagram of a device for calculating pipeline girth weld fracture damage according to an embodiment of the present invention.

[0090] like Figure 8 As shown, the calculation device 10 for pipeline girth weld fracture damage includes: a first calculation module 100, a second calculation module 200, a determination module 300, a third calculation module 400 and a fourth calculation module 500.

[0091] The first calculation module 100 is used to obtain at least one material point corresponding to the girth weld of the target pipeline and calculate the bond constants between different material points; A second calculation module 200 is used to calculate the single bond forces of different material point bonds using the bond constants, and calculate the total bond forces of all material points based on the single bond forces; A determination module 300, for determining the stretching rates of the bonds of different material points according to the motion influence information of the total bond force on at least one material point; The third calculation module 400 is used to calculate the critical stretching rate corresponding to different material point bonds based on the material information of the target pipeline girth weld; The fourth calculation module 500 is used to calculate the damage value of the girth weld of the target pipeline based on the key elongation rate and the critical elongation rate.

[0092] Optionally, in one embodiment of the present invention, the first calculation module 100 includes: a simplification unit, a discretization unit and a generation unit.

[0093] The simplified unit is used to simplify the target pipeline girth weld into a target two-dimensional tetrahedron model having at least one of a base material area, a heat-affected zone and a weld area.

[0094] The discrete unit is used to discretize the material points of the target two-dimensional tetrahedral model to obtain the parent material points located in the parent material area, the heat-affected material points located in the heat-affected zone, and the weld material points located in the weld area in the near field.

[0095] The generating unit is used to obtain at least one material point based on the base material point, the heat affected material point and the weld material point.

[0096] Optionally, in one embodiment of the present invention, the first calculation module 100 includes: a first calculation unit and a second calculation unit.

[0097] The first calculation unit is used to calculate the bond constant using the first bond constant calculation formula when different material points are located in the same area.

[0098] The second calculation unit is used to calculate the bond constant using the second bond constant calculation formula when different material points are located in different areas.

[0099] Optionally, in one embodiment of the present invention, the expression of the first bond constant calculation formula may be, but is not limited to,: , in, is the bond constant, E is the elastic modulus of the corresponding area, is the distance between material points, is the radius of the near field.

[0100] The expression of the second bond constant calculation formula can be, but is not limited to,: , in, is the elastic modulus of the current material point, is the elastic modulus of the material point of the family domain member, is the distance between material points, is the radius of the near field.

[0101] Optionally, in one embodiment of the present invention, the fourth calculation module 500 includes: a judgment unit, a first statistical unit, a second statistical unit and a third calculation unit.

[0102] The judging unit is used to judge whether the stretching rate of the key is greater than the critical stretching rate.

[0103] The first statistical unit is used to determine that the corresponding bond is broken when the stretching rate of the bond is greater than the critical stretching rate, and to count a first number of all broken bonds.

[0104] The second statistical unit is used to determine that the corresponding bond is not broken when the stretching rate of the bond is less than or equal to the critical stretching rate, and to count the second number of all the bonds that are not broken.

[0105] The third calculation unit is used to calculate the damage value based on the first quantity and the second quantity.

[0106] Optionally, in one embodiment of the present invention, the third calculation module 400 includes: a fourth calculation unit and a fifth calculation unit.

[0107] The fourth calculation unit is used to calculate the critical stretch rate using the first critical stretch rate calculation formula when different material points are located in the same area.

[0108] The fifth calculation unit is used to calculate the critical stretch rate by using the second critical stretch rate calculation formula when different material points are located in different areas.

[0109] Optionally, in one embodiment of the present invention, the first critical stretch rate calculation formula may be, but is not limited to,: , in, is the tensile strength of the material, is the elastic modulus.

[0110] The second critical elongation calculation formula may be, but is not limited to,: , in, and are the elastic modulus and critical stretch rate of the current material point, and are the elastic modulus and critical elongation of the domain members, respectively.

[0111] Optionally, in one embodiment of the present invention, the calculation formula of the damage value may be, but is not limited to,: , in, Describe the extent of the injury, represents the number of unbroken bonds of a material point in the near field, Indicates the total number of keys, Represents a key state function.

[0112] It should be noted that the above explanation of the embodiment of the method for calculating the fracture damage of the pipeline girth weld is also applicable to the device for calculating the fracture damage of the pipeline girth weld of this embodiment, and will not be repeated here.

[0113] According to the calculation device for pipeline girth weld fracture damage proposed in the embodiment of the present invention, the bond constant of the material point obtained by simplifying the target pipeline girth weld can be calculated, and then the single bond force and the total bond force can be calculated, and the stretching rate of the bonds of different material points can be determined according to the motion influence information of the total bond force on the material point, and the damage value of the target pipeline girth weld can be calculated based on the stretching rate of the bond and the corresponding critical stretching rate. By considering the geometric structure of the weld area and the material performance characteristics, a near-field dynamics method is adopted to construct a numerical model suitable for the fracture failure of the target pipeline girth weld, which can accurately simulate the brittle fracture process caused by the dynamic expansion of the crack, and fully consider the influence of the parent material area, the weld area and the heat-affected zone, so as to provide an efficient and reliable analysis tool for pipeline safety assessment and life prediction. Therefore, the problems in the related technology that the singularity of the crack tip cannot be effectively solved, especially in the process of high-speed crack expansion, it is difficult to accurately capture the dynamic behavior of the crack tip, resulting in certain limitations in predicting the cracking behavior of the girth weld, and the failure to fully reflect the influence of material properties in different regions on crack expansion under actual working conditions.

[0114] Fig. 9 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of the present invention. The electronic device may include: A memory 901 , a processor 902 , and a computer program stored in the memory 901 and executable on the processor 902 .

[0115] When the processor 902 executes the program, the calculation method of pipeline girth weld fracture damage provided in the above embodiment is implemented.

[0116] Furthermore, the electronic device further comprises: The communication interface 903 is used for communication between the memory 901 and the processor 902 .

[0117] The memory 901 is used to store computer programs that can be executed on the processor 902 .

[0118] The memory 901 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0119] If the memory 901, the processor 902 and the communication interface 903 are implemented independently, the communication interface 903, the memory 901 and the processor 902 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig. 9 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0120] Optionally, in a specific implementation, if the memory 901, the processor 902 and the communication interface 903 are integrated on a chip, the memory 901, the processor 902 and the communication interface 903 can communicate with each other through an internal interface.

[0121] The processor 902 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0122] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned method for calculating the fracture damage of a pipeline girth weld.

[0123] An embodiment of the present invention further provides a computer program product, including a computer program, which implements the above-mentioned method for calculating the fracture damage of the pipeline girth weld when executed.

[0124] 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 N 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.

[0125] In addition, 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 the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0126] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0127] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or N wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0128] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of multiple of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0129] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0130] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0131] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for calculating the fracture damage of a pipeline girth weld, characterized in that: The following steps are involved: Obtain at least one material point corresponding to the girth weld of the target pipeline, and calculate the bond constants between different material points; Calculating the single bond forces of different material point bonds using the bond constants, and calculating the total bond forces of all material points based on the single bond forces; Determining the stretching rates of the bonds at different material points according to the motion influence information of the total bond force on the at least one material point; Based on the material information of the target pipeline girth weld, calculating the critical elongation rates corresponding to the different material point bonds; Based on the key elongation and the critical elongation, a damage value of the target pipeline girth weld is calculated.

2. The calculation method of pipeline girth weld fracture damage according to claim 1 is characterized in that: The obtaining of at least one material point corresponding to the girth weld of the target pipeline includes: Simplifying the target pipeline girth weld into a target two-dimensional tetrahedron model having at least one of a base metal region, a heat-affected zone, and a weld region; Performing material point discretization processing on the target two-dimensional tetrahedron model to obtain parent material points located in the parent material area, heat-affected material points located in the heat-affected zone, and weld material points located in the weld area in the near field; The at least one material point is obtained based on the parent material point, the heat-affected material point and the weld material point.

3. The calculation method of pipeline girth weld fracture damage according to claim 1 is characterized in that: The calculation of the bond constants between different material points includes: When the different material points are located in the same area, the bond constant is calculated using a first bond constant calculation formula; When the different material points are located in different regions, the bond constant is calculated using a second bond constant calculation formula.

4. The method for calculating pipeline girth weld fracture damage according to claim 3 is characterized in that: in, The expression of the first bond constant calculation formula is: ， in, is the bond constant, E is the elastic modulus of the corresponding area, is the distance between material points, is the radius of the near field; The expression of the second bond constant calculation formula is: ， in, is the elastic modulus of the current material point, is the elastic modulus of the material point of the family domain member, is the distance between material points, is the radius of the near field.

5. The calculation method of pipeline girth weld fracture damage according to claim 1 is characterized in that: The step of calculating the damage value of the target pipeline girth weld based on the key elongation rate and the critical elongation rate includes: determining whether the stretching rate of the bond is greater than the critical stretching rate; If the stretching rate of the bond is greater than the critical stretching rate, it is determined that the corresponding bond is broken, and a first number of all broken bonds is counted; If the stretching rate of the bond is less than or equal to the critical stretching rate, it is determined that the corresponding bond is not broken, and a second number of all the bonds that are not broken is counted; The damage value is calculated based on the first number and the second number.

6. The calculation method of pipeline girth weld fracture damage according to claim 1 is characterized in that: The calculating the critical stretching rates corresponding to the different material point bonds includes: When the different material points are located in the same area, the critical stretch rate is calculated using a first critical stretch rate calculation formula; When the different material points are located in different regions, the critical stretch rate is calculated using a second critical stretch rate calculation formula.

7. The calculation method of pipeline girth weld fracture damage according to claim 6 is characterized in that: in, The first critical elongation calculation formula is: ， in, is the tensile strength of the material, is the elastic modulus; The second critical elongation rate calculation formula is: ， in, and are the elastic modulus and critical stretch rate of the current material point, and are the elastic modulus and critical elongation of the domain members, respectively.

8. The method for calculating pipeline girth weld fracture damage according to claim 1, characterized in that: The damage value is calculated as follows: ， in, Describe the extent of the injury, represents the number of unbroken bonds of a material point in the near field, Indicates the total number of keys, Represents a key state function.

9. A calculation device for pipeline girth weld fracture damage, characterized in that: include: A first calculation module is used to obtain at least one material point corresponding to the girth weld of the target pipeline and calculate the bond constants between different material points; A second calculation module is used to calculate the single bond force of different material point bonds using the bond constant, and calculate the total bond force of all material points according to the single bond force; A determination module, configured to determine the stretching rates of the bonds of different material points according to the motion influence information of the total bond force on the at least one material point; A third calculation module is used to calculate the critical elongation rate corresponding to the different material point bonds based on the material information of the target pipeline girth weld; The fourth calculation module is used to calculate the damage value of the target pipeline girth weld based on the key stretch rate and the critical stretch rate.

10. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for calculating the fracture damage of a pipeline girth weld as described in any one of claims 1 to 8.

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