Calculation Method and Device for Fracture Damage of Pipeline Circumferential Weld

Abstract

The present invention relates to the technical field of pipeline damage calculation, and particularly relates to a calculation method and device for the fracture damage of pipeline girth welds. The method includes: obtaining the material points corresponding to the target pipeline girth weld and calculating the bond constants; calculating the single-bond force of the bonds of different material points using the bond constants, and calculating the total bond force of all material points based on the single-bond force; determining the tensile rate of the bonds of different material points according to the motion influence information generated by the total bond force on the material points; calculating the critical tensile rate based on the material information of the target pipeline girth weld; and calculating the damage value of the target pipeline girth weld based on the tensile rate of the bonds and the critical tensile rate. Thereby, it solves the problems in the related technologies that the singularity at 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 girth welds, and failing to comprehensively reflect the influence of the material characteristics of different regions under actual working conditions on crack propagation.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline damage calculation, and particularly relates to a calculation method and device for the fracture damage of pipeline girth welds. Background Art

[0002] The acceleration of the urbanization process and the continuous growth of energy demand have promoted the high-strength steel grade, large diameter, and high-pressure transmission to become an inevitable choice for natural gas pipeline projects. Some major national pipeline projects have gradually taken 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 for pipeline failure.

[0003] In the related art, the GTN model can be used to describe the ductile fracture process of materials. Starting from the microscopic perspective, the plastic deformation and damage failure of materials under stress are related to the behaviors of microvoid nucleation, growth, aggregation, etc. at the microscopic level. By controlling the evolution behavior of microvoids, the deformation and damage process of materials in the macroscopic state can be simulated; or a coupled peridynamics-finite element model can be established, load boundary conditions can be applied, and user-defined subroutines can be used to implement the calculation to predict the ultimate strain capacity of the girth welds of high-strength steel grade pipelines.

[0004] However, in the related art, when solving discontinuous problems such as crack propagation, the singularity at the crack tip cannot be effectively solved. Especially during the high-speed crack propagation process, it is difficult to accurately capture the dynamic behavior of the crack tip. Mesh distortion and singularity assumptions may lead to numerical instability, resulting in certain limitations in predicting the girth weld cracking behavior and failing to fully reflect the influence of material properties in different regions on crack propagation under actual working conditions, which urgently needs to be improved. Summary of the Invention

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

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

[0007] Optionally, in an embodiment of the present invention, the 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 on the target two-dimensional tetrahedral model to obtain base material points in the base material zone, heat-affected material points in the heat-affected zone, and weld material points in the weld zone within the near-field domain; 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 an embodiment of the present invention, the calculating the bond constants between different material points includes: using a first bond constant calculation formula to calculate the bond constant when the different material points are in the same region; and using a second bond constant calculation formula to calculate the bond constant when the different material points are in different regions.

[0009] Optionally, in an embodiment of the present invention, where

[0010] The expression of the first bond constant calculation formula can be but is not limited to:

[0011] ,

[0012] where is the bond constant, E is the elastic modulus of the corresponding region, is the distance between material points, is the radius of the near-field range;

[0013] The expression of the second bond constant calculation formula can be but is not limited to:

[0014] ,

[0015] where 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 range.

[0016] Optionally, in an embodiment of the present invention, calculating the damage value of the target pipeline girth weld based on the stretching rate of the bond and the critical stretching 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, determining that the corresponding bond is broken and counting the first number of all broken bonds; if the stretching rate of the bond is less than or equal to the critical stretching rate, determining that the corresponding bond is not broken and counting the second number of all unbroken bonds; calculating the damage value based on the first number and the second number.

[0017] Optionally, in an embodiment of the present invention, calculating the critical stretching rate corresponding to the bonds of different material points includes: when the different material points are in the same region, calculating the critical stretching rate using the first critical stretching rate calculation formula; when the different material points are in different regions, calculating the critical stretching rate using the second critical stretching rate calculation formula.

[0018] Optionally, in an embodiment of the present invention, where,

[0019] The first critical stretching rate calculation formula can be but is not limited to:

[0020] ,

[0021] where, is the tensile strength of the material, is the elastic modulus;

[0022] The second critical stretching rate calculation formula can be but is not limited to:

[0023] ,

[0024] where, and are respectively the elastic modulus and the critical stretching rate of the current material point, and are respectively the elastic modulus and the critical stretching rate of the family domain member.

[0025] Optionally, in an embodiment of the present invention, the calculation formula of the damage value can be but is not limited to:

[0026] ,

[0027] where, describes the degree of damage, represents the number of unbroken bonds of the material points within the near field range, represents the total number of bonds, represents the bond state function.

[0028] In the embodiment of the second aspect of the present invention, a calculation device for the fracture damage of a pipeline girth weld is provided, including: a first calculation module, configured to obtain at least one material point corresponding to the target pipeline girth weld and calculate the bond constants between different material points; a second calculation module, configured to calculate the single bond force of the bonds between different material points by using the bond constants and calculate the total bond force of all material points according to the single bond force; a determination module, configured to determine the tensile rate of the bonds between different material points according to the motion influence information generated by the total bond force on the at least one material point; a third calculation module, configured to calculate the critical tensile rate corresponding to the bonds between different material points based on the material information of the target pipeline girth weld; a fourth calculation module, configured to calculate the damage value of the target pipeline girth weld based on the tensile rate of the bonds and the critical tensile rate.

[0029] Optionally, in an embodiment of the present invention, the first calculation module includes: a simplification unit, configured to simplify the target pipeline girth weld into a target two-dimensional tetrahedron model having at least one of a base metal area, a heat affected zone, and a weld zone; a discretization unit, configured to perform material point discretization processing on the target two-dimensional tetrahedron model to obtain base metal material points located in the base metal area, heat affected material points located in the heat affected zone, and weld material points located in the weld zone within the near field domain; a generation unit, configured to obtain the at least one material point based on the base metal material points, the heat affected material points, and the weld material points.

[0030] Optionally, in an embodiment of the present invention, the first calculation module includes: a first calculation unit, configured to calculate the bond constant by using a first bond constant calculation formula when the different material points are located in the same area; a second calculation unit, configured to calculate the bond constant by using a second bond constant calculation formula when the different material points are located in different areas.

[0031] Optionally, in an embodiment of the present invention,

[0032] The expression of the first bond constant calculation formula may but is not limited to:

[0033] ,

[0034] Wherein, is the bond constant, E is the elastic modulus of the corresponding area, is the distance between the material points, is the radius of the near field range;

[0035] The expression of the second key constant calculation formula can be, but is not limited to:

[0036] ,

[0037] where, is the elastic modulus of the current material point, is the elastic modulus of the material points of the family domain members, is the spacing between the material points, is the radius of the near-field range.

[0038] Optionally, in an embodiment of the present invention, the fourth calculation module includes: a judgment unit for judging whether the tensile rate of the key is greater than the critical tensile rate; a first statistics unit for determining that the corresponding key is broken when the tensile rate of the key is greater than the critical tensile rate, and counting the first number of all broken keys; a second statistics unit for determining that the corresponding key is not broken when the tensile rate of the key is less than or equal to the critical tensile rate, and counting the second number of all unbroken keys; and a third calculation unit for calculating the damage value based on the first number and the second number.

[0039] Optionally, in an embodiment of the present invention, the third calculation module includes: a fourth calculation unit for calculating the critical tensile rate using the first critical tensile rate calculation formula when the different material points are in the same region; and a fifth calculation unit for calculating the critical tensile rate using the second critical tensile rate calculation formula when the different material points are in different regions.

[0040] Optionally, in an embodiment of the present invention, where,

[0041] The first critical tensile rate calculation formula can be, but is not limited to:

[0042] ,

[0043] where, is the tensile strength of the material, is the elastic modulus;

[0044] The second critical tensile rate calculation formula can be, but is not limited to:

[0045] ,

[0046] where, and are respectively the elastic modulus and the critical tensile rate of the current material point, and are respectively the elastic modulus and the critical tensile rate of the family domain members.

[0047] Optionally, in an embodiment of the present invention, the calculation formula of the damage value may be, but is not limited to:

[0048] ,

[0049] where describes the degree of damage, represents the number of unbroken bonds of the material point within the near - field range, represents the total number of bonds, represents the bond state function.

[0050] An embodiment of the third aspect of the present invention provides an electronic device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the calculation method for the fracture damage of the pipeline girth weld as described in the above - mentioned embodiment.

[0051] An embodiment of the fourth aspect of the present invention provides a computer - readable storage medium, where the computer - readable storage medium stores a computer program, and when the program is executed by a processor, it implements the calculation method for the fracture damage of the pipeline girth weld as above.

[0052] An embodiment of the fifth aspect of the present invention provides a computer program product, including a computer program, and when the program is executed, it implements the calculation method for the fracture damage of the pipeline girth weld as above.

[0053] The embodiments of the present invention can calculate the bond constants of the material points simplified from the target pipeline girth weld, and then calculate the single - bond force and the total bond force. According to the motion influence information generated by the total bond force on the material points, determine the tensile rate of the bonds of different material points, and based on the tensile rate of the bonds and the corresponding critical tensile rate, calculate the damage value of the target pipeline girth weld. By considering the geometric structure and material property characteristics of the weld area, using the peridynamics method, a numerical model suitable for the fracture failure of the target pipeline girth weld is constructed, which can accurately simulate the brittle fracture process caused by the dynamic expansion of cracks, and fully consider the influences of the base metal area, the weld area, and the heat - affected zone, providing an efficient and reliable analysis tool for pipeline safety assessment and life prediction. Thus, it solves the problems in the related technologies that it is impossible to effectively solve the crack - tip singularity, 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 girth weld cracking behavior, and it fails to comprehensively reflect the influence of material characteristics in different regions on crack propagation under actual working conditions.

[0054] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, in which:

[0056] Figure 1 FIG. 4 is a flowchart of a method for calculating the fracture damage of a pipeline girth weld according to an embodiment of the present invention;

[0057] Figure 2 FIG. 5 is a schematic block diagram of the simplification of a pipeline structure according to an embodiment of the present invention;

[0058] Figure 3 FIG. 6 is a schematic block diagram of the regional division according to an embodiment of the present invention;

[0059] Figure 4 FIG. 7 is a schematic diagram of a storage and index array according to an embodiment of the present invention;

[0060] Figure 5 FIG. 8 is a schematic diagram of the bonds formed by material points in the same region and different regions according to an embodiment of the present invention;

[0061] Figure 6 FIG. 9 is a schematic diagram of the peridynamic forces truncating the near-field dynamics acting on the crack surface of a through crack according to an embodiment of the present invention;

[0062] Figure 7 FIG. 10 is a flowchart of the working principle of a method for calculating the fracture damage of a pipeline girth weld according to an embodiment of the present invention;

[0063] Figure 8 FIG. 11 is a schematic block diagram of a calculation device for the fracture damage of a pipeline girth weld according to an embodiment of the present invention;

[0064] Figure 9 FIG. 12 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

[0065] Reference numerals:

[0066] Among them, 201 - base metal zone, 202 - heat affected zone, 203 - weld zone; 10 - calculation device for the fracture damage of a pipeline girth weld; 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 embodiments

[0067] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0068] The calculation method and device for the fracture damage of the girth weld of a pipeline according to an embodiment of the present invention will be described below with reference to the accompanying drawings. Aiming at the problem in the above-mentioned background art that the singularity at 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 comprehensively reflect the influence of the material properties of different regions under actual working conditions on the crack propagation, the present invention provides a calculation method for the fracture damage of the girth weld of a pipeline. In this method, the bond constants of the material points simplified from the target pipeline girth weld can be calculated, and then the single bond force and the total bond force can be calculated. According to the information on the motion influence generated by the total bond force on the material points, the tensile rate of the bonds of different material points can be determined, and based on the tensile rate of the bonds and the corresponding critical tensile rate, the damage value of the target pipeline girth weld can be calculated. By considering the geometric structure and material performance characteristics of the weld area and adopting the peridynamics method, a numerical model suitable for the fracture failure of the target pipeline girth weld is constructed, which can accurately simulate the brittle fracture process caused by the dynamic propagation of cracks and fully consider the influence of the base metal area, the weld area, and the heat-affected zone, providing an efficient and reliable analysis tool for pipeline safety assessment and life prediction. Thus, the problems in the related art, such as the inability to effectively solve the singularity at the crack tip, especially in the process of high-speed crack propagation, the difficulty in accurately capturing the dynamic behavior of the crack tip, resulting in certain limitations in predicting the cracking behavior of the girth weld, and the failure to comprehensively reflect the influence of the material properties of different regions under actual working conditions on the crack propagation, are solved.

[0069] Specifically, Figure 1 FIG. is a flowchart of a calculation method for the fracture damage of the girth weld of a pipeline according to an embodiment of the present invention.

[0070] As Figure 1 shown, the calculation method for the fracture damage of the girth weld of the pipeline includes the following steps:

[0071] In step S101, at least one material point corresponding to the target pipeline girth weld is obtained, and the bond constants between different material points are calculated.

[0072] It can be understood that the embodiments of the present invention mainly calculate the fracture damage of the girth weld for high-strength steel. The girth weld is a crucial connecting part in pipeline engineering, and its quality directly affects the safe and stable operation of the pipeline system. The embodiments of the present invention can determine the corresponding material points for high-strength steel pipelines.

[0073] In some embodiments, the embodiments of the present invention can perform material point discretization based on the circumferential weld of the target pipeline, such as the circumferential weld of high-strength steel pipeline, so as to obtain at least one material point, and calculate the bond constants between different material points through corresponding calculation formulas.

[0074] Optionally, in an embodiment of the present invention, obtaining at least one material point corresponding to the circumferential weld of the target pipeline includes: simplifying the circumferential weld of the target pipeline into a target two-dimensional tetrahedron model having at least one of a base metal area, a heat-affected zone, and a weld zone; performing material point discretization on the target two-dimensional tetrahedron model to obtain base metal material points located in the base metal area, heat-affected material points located in the heat-affected zone, and weld material points located in the weld zone within the near field; and obtaining at least one material point based on the base metal material points, heat-affected material points, and weld material points.

[0075] As a possible implementation manner, the embodiments of the present invention can approximate the target pipeline as a plane stress state according to the structural characteristics of the large diameter and thin wall of the target pipeline. Therefore, the target pipeline with a three-dimensional cylindrical structure is simplified into a target two-dimensional tetrahedron model, and its schematic diagram is as Figure 2 shown. The length direction is the axial direction of the pipeline, and the width direction is the pipeline wall thickness direction. This model can but is not limited to including a base metal area 201, a heat-affected zone 202, a weld zone 203, etc., and the present invention does not make specific limitations. Among them, the base metal area 201 can represent the main material X80 steel grade of the target pipeline and is distributed on both sides of the weld; the weld zone 203 can represent the area filled with welding materials and is usually located at the center of the model; the heat-affected zone 202 can represent the area where the material properties change due to the influence of welding heating between the weld zone 203 and the base metal area 201, and the width is generally determined according to experiments.

[0076] Furthermore, the embodiments of the present invention can perform material point discretization on the target two-dimensional tetrahedron model to obtain base metal material points located in the base metal area 201, heat-affected material points located in the heat-affected zone 202, and weld material points located in the weld zone 203 within the near field. Its schematic diagram is as Figure 3 shown.

[0077] In addition, it should be noted that the embodiments of the present invention can determine the family domain members within the near field of each material point and store their relationships in a relevant array. Its schematic diagram is as Figure 4 shown. Among them, in Figure 4 , i is the number of the material point itself, numfam is the number of family domain members, pointfam is the starting number of the material point family domain members in the family domain group, and nodefam is the material point family domain group number.

[0078] Optionally, in an embodiment of the present invention, calculating the bond constant between different material points includes: when different material points are located in the same region, calculating the bond constant using the first bond constant calculation formula; when different material points are located in different regions, calculating the bond constant using the second bond constant calculation formula. Among them, the expression of the first bond constant calculation formula can be but is not limited to:

[0079] ,

[0080] Among them, is the bond constant, E is the elastic modulus of the corresponding region, is the distance between material points, is the radius of the near-field range.

[0081] The expression of the second bond constant calculation formula can be but is not limited to:

[0082] ,

[0083] Among them, 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 range.

[0084] It can be understood that in the embodiment of the present invention, the bond constant can be a parameter used to describe the interaction strength between two material points. Since the weld zone, heat-affected zone, and base metal zone have different material properties, the difference in bond constants can accurately reflect the mechanical differences in these regions. By calculating the bond constants of different regions, the propagation path of cracks in different material regions can be better simulated. Among them, as Figure 5 shows, the embodiment of the present invention provides bonds composed of material points in the same region and different regions. Among them, and The bond between is the bond between the heat-affected zone 202 and the weld zone 203, which belongs to a cross-region bond; while and The bond between is the bond of the weld zone 203 in the same region, which belongs to the bond of the same region.

[0085] In some embodiments, when calculating the bond constant between different material points in the embodiment of the present invention, the crack information of the target pipeline girth weld can be obtained first, and its schematic diagram can be as Figure 6 shown, and initial cracks are set at angles of 0°, 15°, 30°, 45°, 60°, 75°, and 90°.

[0086] Further, in the embodiments of the present invention, when the material points are located in the same region, the calculation formula for the bond constant is the first bond constant calculation formula, and its expression can be but is not limited to:

[0087] ,

[0088] wherein, is the bond constant, E is the elastic modulus of the corresponding region, is the distance between the material points, is the radius of the near-field range.

[0089] When the material points are located in different regions, the calculation formula for the bond constant is the second bond constant calculation formula, and its expression can be but is not limited to:

[0090] ,

[0091] wherein, is the elastic modulus of the current material point, is the elastic modulus of the material points of the family domain members, is the distance between the material points, is the radius of the near-field range.

[0092] Further, in the embodiments of the present invention, when the material points and their neighborhood members are in different regions (for example, the weld zone and the heat-affected zone), in order to better describe the interaction between two different materials, the average value of their elastic moduli can be adopted, so as to better reflect the mechanical transition between different materials and more accurately simulate the cracking behavior.

[0093] In step S102, the single bond force of the bonds between different material points is calculated using the bond constant, and the total bond force of all material points is calculated based on the single bond force.

[0094] In some embodiments, when calculating the total bond force in the embodiments of the present invention, the single bond force is first calculated according to the bond constant, and its calculation formula can be but is not limited to:

[0095] ,

[0096] wherein, represents the coordinate of the material point after deformation, represents the coordinate of the material point itself after deformation, represents the coordinate of the material point before deformation, represents the coordinate of the material point itself before deformation, represents the bond strain, i.e., the tensile rate of the bond. The denominator represents the length of the bond after deformation minus the initial length of the bond, represents the direction vector of the bond after deformation, Represents the bond constant, which is multiplied by the bond constant value corresponding to each bond when calculating the bond force. Represents the corrected volume. Represents the surface correction factor.

[0097] Furthermore, after calculating the force of a single bond in the embodiment of the present invention, integral summation can be adopted to further calculate the total bond force.

[0098] In step S103, according to the motion influence information generated by the total bond force on at least one material point, the stretching rate of the bonds of different material points is determined.

[0099] It can be understood that the stretching rate of the bond is caused by the influence of the total bond force on the motion of the material point, which in turn leads to a change in the displacement of the material point. Therefore, in the embodiment of the present invention, according to the motion influence information generated by the total bond force on at least one material point, the stretching rate of the bonds of different material points is determined. Among them, the calculation formula of the stretching rate of the bond can be, but is not limited to:

[0100] ,

[0101] Wherein, Represents the coordinate of the material point after deformation. Represents the coordinate of the material point itself after deformation. Represents the coordinate of the material point before deformation. Represents the coordinate of the material point itself before deformation.

[0102] In step S104, based on the material information of the circumferential weld of the target pipeline, the critical stretching rate corresponding to the bonds of different material points is calculated.

[0103] It can be understood that in the embodiment of the present invention, the critical stretching rate is related to the material information of the circumferential weld of the target pipeline. Therefore, in the embodiment of the present invention, the corresponding critical stretching rate can be calculated through the material information of the circumferential weld of the target pipeline.

[0104] Optionally, in an embodiment of the present invention, calculating the critical stretching rate corresponding to the bonds of different material points includes: when different material points are in the same region, using the first critical stretching rate calculation formula to calculate the critical stretching rate; when different material points are in different regions, using the second critical stretching rate calculation formula to calculate the critical stretching rate. Among them, the first critical stretching rate calculation formula can be, but is not limited to:

[0105] ,

[0106] Wherein, Is the tensile strength of the material. Is the elastic modulus.

[0107] The second critical stretching rate calculation formula can be, but is not limited to:

[0108] ,

[0109] Among them, and are the elastic modulus and critical tensile rate of the current material point respectively, and are the elastic modulus and critical tensile rate of the family domain members respectively.

[0110] In some embodiments, when calculating the critical tensile rate in the embodiments of the present invention, when the material point and its neighborhood members are in the same region, the calculation formula of the critical tensile rate is the first critical tensile rate calculation formula, and its expression can be but is not limited to:

[0111] ,

[0112] Among them, is the tensile strength of the material, is the elastic modulus.

[0113] In some embodiments, when calculating the critical tensile rate in the embodiments of the present invention, when the material point and its neighborhood members are in different regions, the calculation formula of the critical tensile rate is the second critical tensile rate calculation formula, and its expression can be but is not limited to:

[0114] ,

[0115] Among them, and are the elastic modulus and critical tensile rate of the current material point respectively, and are the elastic modulus and critical tensile rate of the family domain members respectively.

[0116] Among them, in order to reflect the mechanical properties of material points in different regions, the embodiments of the present invention can adopt a weighted average based on the elastic modulus. The elastic modulus is a measure of the rigidity of the material, and a larger elastic modulus corresponds to a greater resistance to deformation. Therefore, the embodiments of the present invention play a weighting role in the calculation of the critical tensile rate in different regions.

[0117] In step S105, based on the tensile rate and critical tensile rate of the bond, calculate the damage value of the target pipeline girth weld.

[0118] As a possible implementation manner, the embodiments of the present invention can compare the tensile rate of each bond with the corresponding critical tensile rate after calculating the tensile rate of each bond, determine whether the bond is broken, and further obtain the damage value of the target pipeline girth weld.

[0119] Optionally, in an embodiment of the present invention, based on the stretching rate of the bond and the critical stretching rate, calculating the damage value of the target pipeline girth weld 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, determining that the corresponding bond is broken, and counting the first number of all broken bonds; if the stretching rate of the bond is less than or equal to the critical stretching rate, determining that the corresponding bond is not broken, and counting the second number of all unbroken bonds; calculating the damage value based on the first number and the second number. Among them, the calculation formula of the damage value can be but is not limited to:

[0120] ,

[0121] Among them, describes the degree of damage, represents the number of broken bonds of the material point within the near-field range, represents the total number of bonds.

[0122] In some embodiments, if the stretching rate of the bond in the embodiment of the present invention is greater than the critical stretching rate, it is determined that the corresponding bond is broken, and the bond state function is set to 0, and then the first number of all broken bonds is counted.

[0123] In some embodiments, if the stretching rate of the bond in the embodiment of the present invention is less than or equal to the critical stretching rate, it is determined that the corresponding bond is not broken, and the bond state function is set to 1, and then the second number of all broken bonds is counted.

[0124] Furthermore, the embodiment of the present invention can calculate the damage value according to the first number and the second number. Among them, the calculation formula of the damage value can be but is not limited to:

[0125] ,

[0126] Among them, describes the degree of damage, represents the number of unbroken bonds of the material point within the near-field range, represents the total number of bonds, represents the bond state function.

[0127] Among them, in the embodiment of the present invention, the bond state function is related to the pair force between the material points and the elongation rate between the mass points. When the bond strain exceeds the critical strain, the bond will break, the pair force between the material points disappears, and the material points are damaged. Its expression can be but is not limited to:

[0128] .

[0129] Next, the working principle of the calculation method for the fracture damage of the pipeline girth weld proposed in the embodiment of the present invention will be introduced in combination with a specific embodiment.

[0130] Among them, Figure 7 is a flowchart of the working principle of the calculation method for the fracture damage of the circumferential weld of a pipeline provided according to an embodiment of the present invention.

[0131] Step S701: Obtain the material information corresponding to the circumferential weld of the pipeline.

[0132] Step S702: Simplify the circumferential weld of the pipeline into a two-dimensional tetrahedron model.

[0133] Step S703: Perform material point discretization on the two-dimensional tetrahedron model to obtain the material points corresponding to the base metal area, heat affected zone, and weld zone within the near field domain.

[0134] Step S704: Calculate the bond constant.

[0135] Among them, in the embodiment of the present invention, when different material points are in the same region, the first bond constant calculation formula is used to calculate the bond constant; when different material points are in different regions, the second bond constant calculation formula is used to calculate the bond constant.

[0136] Step S705: Load the initial boundary conditions.

[0137] Among them, in the embodiment of the present invention, the initial boundary conditions can be loaded on the circumferential weld of the pipeline to simulate the stress conditions of different material points of the circumferential weld of the pipeline.

[0138] Step S706: Calculate the total bond force.

[0139] Among them, in the embodiment of the present invention, the single bond force can be calculated according to the bond constant, and after calculating the single bond force, the total bond force is calculated by integral summation.

[0140] Step S707: Calculate the tensile rate of the bond.

[0141] Among them, in the embodiment of the present invention, the tensile rate of the bond of different material points can be determined according to the motion influence information generated by the total bond force on at least one material point.

[0142] Step S708: Calculate the critical tensile rate.

[0143] Among them, in the embodiment of the present invention, when different material points are in the same region, the first critical tensile rate calculation formula is used to calculate the critical tensile rate; when different material points are in different regions, the second critical tensile rate calculation formula is used to calculate the critical tensile rate.

[0144] Step S709: Determine whether the tensile rate of the bond is greater than the critical tensile rate.

[0145] Among them, in the embodiment of the present invention, if the tensile rate of the bond is greater than the critical tensile rate, step S710 is executed; otherwise, step S711 is executed.

[0146] Step S710: The key breaks.

[0147] Step S711: The key does not break.

[0148] Among them, in the case where the key does not break in the embodiment of the present invention, the initial boundary conditions can be reloaded.

[0149] Step S712: Calculate the damage value.

[0150] Among them, in the embodiment of the present invention, the damage value of the pipeline girth weld can be calculated according to the number of broken keys.

[0151] According to the calculation method of pipeline girth weld fracture damage proposed by the embodiment of the present invention, the bond constants of the material points simplified from the target pipeline girth weld can be calculated, and then the single bond force and the total bond force can be calculated. According to the motion influence information generated by the total bond force on the material points, the stretching rate of the bonds of different material points can be determined, and based on the stretching rate of the bonds and the corresponding critical stretching rate, the damage value of the target pipeline girth weld can be calculated. By considering the geometric structure and material property characteristics of the weld area and adopting the peridynamics method, a numerical model suitable for the fracture failure of the target pipeline girth weld is constructed, which can accurately simulate the brittle fracture process caused by the dynamic propagation of cracks, and fully consider the influence of the base metal area, the weld area and the heat affected zone, providing an efficient and reliable analysis tool for pipeline safety assessment and life prediction. Thus, in the related technology, the singularity at 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 characteristics in different regions under actual working conditions on crack propagation and other problems are solved.

[0152] Next, a calculation device for pipeline girth weld fracture damage proposed according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0153] Figure 8 It is a block diagram of a calculation device for pipeline girth weld fracture damage provided according to an embodiment of the present invention.

[0154] As Figure 8 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.

[0155] Among them, the first calculation module 100 is used to obtain at least one material point corresponding to the target pipeline girth weld and calculate the bond constants between different material points;

[0156] The second calculation module 200 is configured to calculate the single bond force of the bonds of different material points by using the bond constant, and calculate the total bond force of all material points according to the single bond force;

[0157] The determination module 300 is configured to determine the stretching rate of the bonds of different material points according to the motion influence information generated by the total bond force on at least one material point;

[0158] The third calculation module 400 is configured to calculate the critical stretching rate corresponding to the bonds of different material points based on the material information of the target pipeline girth weld;

[0159] The fourth calculation module 500 is configured to calculate the damage value of the target pipeline girth weld based on the stretching rate and the critical stretching rate of the bond.

[0160] Optionally, in an embodiment of the present invention, the first calculation module 100 includes: a simplification unit, a discretization unit, and a generation unit.

[0161] Wherein, the simplification unit is configured to simplify the target pipeline girth weld into a target two-dimensional tetrahedral model having at least one of a base metal zone, a heat affected zone, and a weld zone.

[0162] The discretization unit is configured to perform material point discretization on the target two-dimensional tetrahedral model to obtain base metal material points located in the base metal zone, heat affected material points located in the heat affected zone, and weld material points located in the weld zone within the near field domain.

[0163] The generation unit is configured to obtain at least one material point based on the base metal material points, the heat affected material points, and the weld material points.

[0164] Optionally, in an embodiment of the present invention, the first calculation module 100 includes: a first calculation unit and a second calculation unit.

[0165] Wherein, the first calculation unit is configured to calculate the bond constant by using the first bond constant calculation formula when different material points are located in the same region.

[0166] The second calculation unit is configured to calculate the bond constant by using the second bond constant calculation formula when different material points are located in different regions.

[0167] Optionally, in an embodiment of the present invention, the expression of the first bond constant calculation formula may be, but is not limited to:

[0168] ,

[0169] Wherein, is the bond constant, E is the elastic modulus of the corresponding region, is the distance between material points, is the radius of the near field range.

[0170] The expression of the second key constant calculation formula can be but is not limited to:

[0171] ,

[0172] where, is the elastic modulus of the current material point, is the elastic modulus of the material points of the family domain members, is the spacing between the material points, is the radius of the near-field range.

[0173] Optionally, in an embodiment of the present invention, the fourth calculation module 500 includes: a judgment unit, a first statistics unit, a second statistics unit, and a third calculation unit.

[0174] Among them, the judgment unit is used to judge whether the tensile rate of the key is greater than the critical tensile rate.

[0175] The first statistics unit is used to determine that the corresponding key is broken when the tensile rate of the key is greater than the critical tensile rate, and count the first quantity of all broken keys.

[0176] The second statistics unit is used to determine that the corresponding key is not broken when the tensile rate of the key is less than or equal to the critical tensile rate, and count the second quantity of all unbroken keys.

[0177] The third calculation unit is used to calculate the damage value based on the first quantity and the second quantity.

[0178] Optionally, in an embodiment of the present invention, the third calculation module 400 includes: a fourth calculation unit and a fifth calculation unit.

[0179] Among them, the fourth calculation unit is used to calculate the critical tensile rate by using the first critical tensile rate calculation formula when different material points are in the same region.

[0180] The fifth calculation unit is used to calculate the critical tensile rate by using the second critical tensile rate calculation formula when different material points are in different regions.

[0181] Optionally, in an embodiment of the present invention, among them, the first critical tensile rate calculation formula can be but is not limited to:

[0182] ,

[0183] where, is the tensile strength of the material, is the elastic modulus.

[0184] The second critical tensile rate calculation formula can be but is not limited to:

[0185] ,

[0186] Wherein, and are the elastic modulus and critical tensile rate of the current material point respectively, and are the elastic modulus and critical tensile rate of the domain members respectively.

[0187] Optionally, in an embodiment of the present invention, the calculation formula of the damage value may but is not limited to:

[0188] ,

[0189] Wherein, describes the degree of damage, represents the number of unbroken bonds of the material point within the near field range, represents the total number of bonds, represents the bond state function.

[0190] It should be noted that the foregoing explanation of the embodiment of the calculation method for the fracture damage of the pipeline girth weld also applies to the calculation device for the fracture damage of the pipeline girth weld in this embodiment, and will not be elaborated herein.

[0191] The calculation device for the fracture damage of the pipeline girth weld proposed according to the embodiment of the present invention can calculate the bond constants of the material points simplified from the target pipeline girth weld, and then calculate the single bond force and the total bond force. Based on the motion influence information generated by the total bond force on the material points, it determines the tensile rate of the bonds of different material points, and calculates the damage value of the target pipeline girth weld based on the tensile rate of the bonds and the corresponding critical tensile rate. By considering the geometric structure and material property characteristics of the weld area and adopting the peridynamics method, it constructs a numerical model for the fracture failure of the target pipeline girth weld, which can accurately simulate the brittle fracture process caused by the dynamic propagation of cracks, and fully consider the influences of the base metal area, the weld area and the heat affected zone, providing an efficient and reliable analysis tool for pipeline safety assessment and life prediction. Thus, it solves the problems in the related art that the crack tip singularity 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 girth weld cracking behavior and failing to fully reflect the influence of the material characteristics of different regions under actual working conditions on the crack propagation.

[0192] Figure 9 FIG. is a schematic structural diagram of an electronic device provided according to an embodiment of the present invention. The electronic device may include:

[0193] A memory 901, a processor 902, and a computer program stored on the memory 901 and executable on the processor 902.

[0194] When the processor 902 executes a program, it implements the calculation method for the fracture damage of the pipeline girth weld provided in the above embodiments.

[0195] Furthermore, the electronic device further includes:

[0196] A communication interface 903 for communication between the memory 901 and the processor 902.

[0197] A memory 901 for storing a computer program that can run on the processor 902.

[0198] The memory 901 may include a high-speed RAM memory, and may also include a non-volatile memory, such as at least one disk memory.

[0199] 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 interconnected 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, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 9 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0200] 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.

[0201] 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.

[0202] The embodiments of the present invention further provide a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, it implements the above calculation method for the fracture damage of the pipeline girth weld.

[0203] An embodiment of the present invention further provides a computer program product, including a computer program which, when executed, implements the calculation method for the fracture damage of the pipeline girth weld as described above.

[0204] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection 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 can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0205] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0206] Any process or method description shown in the flowchart or described in other ways herein can be understood as representing a module, segment, or part of code including one or N executable instructions for implementing a customized logic function or process, and the scope of the preferred embodiment of the present invention includes additional implementations, where the functions can be executed in a substantially simultaneous manner or in the reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of the present invention belong.

[0207] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definable sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or used in combination with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion (electronic device) having one or N wirings, a portable computer disk cartridge (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or other appropriate processing as necessary, and then stored in a computer memory.

[0208] It should be understood that various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, 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 in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0209] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the method of the above-described embodiments can be completed by a program instructing relevant hardware, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0210] In addition, each functional unit in various embodiments of the present invention may be integrated into a processing module, may exist separately physically for each unit, 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. When 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.

[0211] The above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disc, 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 should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A calculation method for the fracture damage of the circumferential weld of a pipeline, characterized in that, It includes the following steps: Obtain at least one material point corresponding to the girth weld of the target pipeline, and calculate the bond constants between different material points; Calculate the single bond force of the bonds between different material points by using the bond constants, and calculate the total bond force of all material points according to the single bond force; Determine the tensile rate of the bonds between different material points according to the motion influence information generated by the total bond force on the at least one material point; Calculate the critical tensile rate corresponding to the bonds between different material points based on the material information of the girth weld of the target pipeline; Calculate the damage value of the girth weld of the target pipeline based on the tensile rate of the bonds and the critical tensile rate; Among them, the obtaining of at least one material point corresponding to the girth weld of the target pipeline includes: Simplify the girth weld of the target pipeline into a target two-dimensional tetrahedral model having at least one of a base metal zone, a heat affected zone, and a weld zone; Perform material point discretization on the target two-dimensional tetrahedral model to obtain base metal material points located in the base metal zone, heat affected material points located in the heat affected zone, and weld material points located in the weld zone within the near field; Based on the base metal material points, the heat affected material points, and the weld material points, obtain the at least one material point; The calculating of the bond constants between different material points includes: When the different material points are in the same region, calculate the bond constant by using a first bond constant calculation formula; When the different material points are in different regions, calculate the bond constant by using a second bond constant calculation formula; The expression of the first bond constant calculation formula is: ， Among them, is the key constant, E is the elastic modulus of the corresponding region, is the distance between material points, is the radius of the near-field range; The expression of the second bond constant calculation formula is: ， Among them, is the elastic modulus of the current material point, is the elastic modulus of the material points of the family domain members, is the distance between material points, is the radius of the near-field range.

2. The calculation method for the fracture damage of the circumferential weld of the pipeline according to claim 1, characterized in that, The calculating of the damage value of the girth weld of the target pipeline based on the tensile rate of the bonds and the critical tensile rate includes: Judge whether the tensile rate of the bonds is greater than the critical tensile rate; If the tensile rate of the bonds is greater than the critical tensile rate, determine that the corresponding bond is broken, and count the first number of all broken bonds; If the tensile rate of the bonds is less than or equal to the critical tensile rate, determine that the corresponding bond is not broken, and count the second number of all unbroken bonds; Calculate the damage value based on the first number and the second number.

3. The calculation method for the fracture damage of the circumferential weld of the pipeline according to claim 1, characterized in that, The calculating of the critical tensile rate corresponding to the bonds between different material points includes: When the different material points are in the same region, calculate the critical tensile rate by using a first critical tensile rate calculation formula; When the different material points are in different regions, calculate the critical tensile rate by using a second critical tensile rate calculation formula.

4. The calculation method for the fracture damage of the girth weld of the pipeline according to claim 3, characterized in that Among them, The first critical tensile rate calculation formula is: ， Among them, is the tensile strength of the material, is the elastic modulus; The second critical tensile rate calculation formula is: ， Among them, and are the elastic modulus and critical tensile rate of the current material point respectively, and are the elastic modulus and critical tensile rate of the family domain members respectively.

5. The calculation method for the fracture damage of the circumferential weld of the pipeline according to claim 1, wherein, The calculation formula of the damage value is: ， Among them, Describes the degree of damage, Indicates the number of unbroken bonds of the material point within the near-field range, Indicates the total number of bonds, Indicates the bond state function.

6. A calculation device for the fracture damage of the circumferential weld of a pipeline, characterized in that, It includes: A first calculation module for obtaining at least one material point corresponding to the girth weld of the target pipeline and calculating the bond constants between different material points; A second calculation module for calculating the single bond force of the bonds between different material points by using the bond constants and calculating the total bond force of all material points according to the single bond force; A determination module for determining the tensile rate of the bonds between different material points according to the motion influence information generated by the total bond force on the at least one material point; A third calculation module, configured to calculate a critical tensile rate corresponding to the different material point bonds based on the material information of the target pipeline girth weld; A fourth calculation module, configured to calculate a damage value of the target pipeline girth weld based on the tensile rate of the bond and the critical tensile rate; Wherein, the first calculation module includes: A simplification unit, configured to simplify the target pipeline girth weld into a target two-dimensional tetrahedral model having at least one of a base metal area, a heat affected zone, and a weld zone; A discretization unit, configured to perform material point discretization processing on the target two-dimensional tetrahedral model to obtain base metal material points located in the base metal area, heat affected material points located in the heat affected zone, and weld material points located in the weld zone within the near field region; A generation unit, configured to obtain the at least one material point based on the base metal material points, the heat affected material points, and the weld material points; The first calculation module includes: A first calculation unit, configured to calculate the bond constant using a first bond constant calculation formula when the different material points are located in the same area; A second calculation unit, configured to calculate the bond constant using a second bond constant calculation formula when the different material points are located in different areas; The expression of the first bond constant calculation formula is: ， Among them, is the key constant, E is the elastic modulus of the corresponding region, is the distance between material points, is the radius of the near-field range; The expression of the second bond constant calculation formula is: ， Among them, is the elastic modulus of the current material point, is the elastic modulus of the material points of the family domain members, is the distance between the material points, is the radius of the near-field range.

7. An electronic device, characterized in that, Including: A memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the calculation method for pipeline girth weld fracture damage according to any one of claims 1-5.

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