Nonlinear finite element analysis method for crimping strength of steel wire rope of electric connector

Abstract

The invention discloses a nonlinear finite element analysis method for crimping strength of a steel wire rope of an electric connector. The nonlinear finite element analysis method comprises the following steps: establishing an actual geometric model of a winding state of the steel wire rope and performing fine grid division; defining elastic-plastic constitutive parameters and contact attributes of the material; carrying out axial tensile numerical simulation on the steel wire rope based on a dynamic explicit algorithm, and carrying out iterative calibration on constitutive parameters of a material in combination with fracture strain of the material and a minimum fracture force index of the steel wire rope to ensure simulation precision; finite element models of the pressure head and the sleeve shell are established and assembled; a dynamic explicit method is adopted to set stamping and stretching analysis steps in sequence, nonlinear numerical simulation of the whole stamping-stretching process is completed, and stress, strain and deformation results are output; and finally, evaluating whether the crimping strength meets design requirements according to a simulation result. Through parameter calibration and whole-process explicit dynamics simulation, a high-precision and high-efficiency numerical analysis tool is provided for structural design and process optimization of the aviation electric connector.

Description

A Nonlinear Finite Element Analysis Method for the Crimping Strength of Steel Wire Ropes in Electrical Connectors Technical Field

[0001] This invention relates to the field of aviation electrical connectors, and in particular to a nonlinear finite element analysis method for the crimping strength of steel wire ropes in electrical connectors. Background Technology

[0002] Steel wire rope, as a flexible helical steel structure, is widely used in the pull-out mechanism of aerospace electrical connectors due to its high strength and good flexibility. The core of the reliability of this type of connector lies in whether the steel wire rope, after being connected to the metal housing through a stamping process, can remain in place under ultimate tensile load, that is, whether the crimping strength meets the requirements.

[0003] However, due to the complex helical winding structure of the steel wire rope and the fact that the crimping process involves large plastic deformation of the material, multi-body nonlinear contact, and the coupling effect of stamping and tension, it is extremely difficult to directly and accurately determine its crimping strength through traditional physical tests. In the test, stress concentration is prone to occur at the load application point, causing the steel wire rope to often break outside the crimping zone, which cannot truly reflect the failure strength of the crimping interface.

[0004] With the development of computer technology, the finite element method has become a powerful tool for analyzing the mechanical behavior of complex structures. Currently, finite element studies on wire ropes mostly focus on the tensile properties of the rope itself or the analysis of its braiding formation. However, for its strength after assembly in specific components (such as connector housings), especially its ultimate tensile behavior after stamping plastic deformation, a systematic and high-fidelity crimping strength analysis method is still lacking. Existing technologies often simplify the process by using the linear elastic assumption of the material, which cannot accurately predict the nonlinear failure process under extreme conditions. Therefore, developing a nonlinear finite element analysis method that can accurately simulate the entire crimping-tensioning process of wire ropes and effectively evaluate their crimping strength has significant engineering value for improving the design reliability and R&D efficiency of aerospace electrical connectors. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies, such as the difficulty in directly measuring the crimping strength of steel wire ropes through experiments and the inability to accurately simulate the nonlinear failure process of steel wire ropes under ultimate tension after crimping. This invention provides a high-precision and high-efficiency nonlinear finite element analysis method for the crimping strength of steel wire ropes in electrical connectors.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a nonlinear finite element analysis method for the crimping strength of steel wire rope in an electrical connector, comprising the following steps: S1, establishing a geometric model of the steel wire rope winding state based on the actual structural characteristics of the steel wire rope, and meshing the steel wire rope based on the geometric model to construct a finite element model of the steel wire rope; S2, defining the elasto-plastic constitutive parameters and contact properties of the steel wire rope material; S3, establishing a dynamic explicit calculation and analysis step for the axial tension of the steel wire rope, setting boundary conditions at both ends of the steel wire rope to perform tensile numerical simulation, and outputting tensile force, tensile displacement, stress, and strain results; S4, based on the fracture strain of the steel wire rope material... The minimum breaking tensile force index of the wire rope is used to iteratively calibrate the elastic-plastic constitutive parameters; S5, establish the geometric model of the casing and two opposing indenters and perform mesh generation, construct the finite element model of the casing and the indenter, and complete the assembly of the finite element model of the casing and the indenter with the finite element model of the wire rope; S6, using the dynamic explicit method, establish the stamping analysis step and the tensile analysis step in sequence, define the loads and boundary conditions of the indenter, casing and wire rope in the stamping analysis step and the tensile analysis step, complete the numerical simulation of the entire stamping-tensile process, and output the simulation results; S7, evaluate the crimping strength of the wire rope based on the simulation results.

[0007] In one embodiment, when establishing the geometric model of the wire rope winding state in step S1, a spacing is set between the circular cross-sections of each wire strand, and the spacing is 0.5%-2% of the diameter of a single wire strand.

[0008] In one embodiment, during mesh generation in step S1, the half-width of the contact surface between each wire is determined according to Hertzian contact theory. And set the minimum grid size of the contact area to / 2 to / 3.

[0009] In one embodiment, in step S2, the elastoplastic constitutive parameters are defined using a linearly strengthened ideal elastoplastic model, and the elastoplastic constitutive parameters include the initial yield stress. Ultimate stress and the fracture strain corresponding to the ultimate stress .

[0010] In one embodiment, in step S4, the iterative calibration specifically involves: repeatedly adjusting the ultimate stress. The values ​​of [value] are used to perform tensile simulations until the steel wire rope reaches the aforementioned fracture strain in the simulation. The deviation between the tensile force corresponding to the minimum breaking tensile force and the minimum breaking tensile force index is within a preset threshold.

[0011] In one embodiment, the preset threshold is 5%.

[0012] In one embodiment, in step S6, during the stamping analysis step, opposing vertical displacement loads are applied to the two pressure heads; during the tensile analysis step, a specified tensile force is applied to one end of the wire rope, and a fixed constraint is applied to the end face of the casing on one side along the tensile direction.

[0013] In one embodiment, the method further includes step S8: performing parametric simulations of different indenter displacements, punching forces, or casing geometry based on calibrated material parameters and the established finite element model, in order to optimize the pressing process.

[0014] In one embodiment, the finite element model of the wire rope, the finite element model of the pressure head, and the finite element model of the casing are all modeled using eight-node reduced integral solid elements.

[0015] In one embodiment, in step S7, if the simulation results show that the wire rope does not come out of the casing and the maximum equivalent stress does not exceed the material's ultimate stress under the specified tensile load, then the crimping strength is determined to meet the requirements.

[0016] Beneficial effects: Compared with the prior art, the beneficial effects of the present invention are as follows: By establishing a realistic geometric model, refining the mesh, and iteratively calibrating the material parameters, the present invention constructs a finite element model that can accurately simulate the entire process of steel wire rope crimping-tensioning, solving the engineering problem that physical experiments are difficult to directly measure the strength of the crimping interface, and significantly reducing the research and development cost and cycle.

[0017] This invention fully considers material nonlinearity (elastoplasticity), geometric nonlinearity (large deformation), and contact nonlinearity, and can simulate the entire process from elastic and plastic yielding to failure, overcoming the defect that traditional linear elastic analysis cannot predict the limit state.

[0018] The material parameter iterative calibration method based on minimum breaking tensile force and fracture strain proposed in this invention can ensure that the deviation between the simulated ultimate tensile force and the value specified by the national standard is less than 5% even in the absence of detailed material constitutive curves, which greatly improves the reliability and direct usability of numerical analysis results.

[0019] This invention uses parametric simulation based on a calibrated model to systematically study the influence of process parameters such as press head stroke and punching force on the pressing strength, providing a quantitative basis for product design and process optimization. Attached Figure Description

[0020] Figure 1 is a flowchart of the nonlinear finite element analysis method for the crimping strength of the electrical connector steel wire rope according to an embodiment of the present invention; Figure 2 is a schematic diagram of the finite element model and cross-section of the steel wire rope according to an embodiment of the present invention; Figure 3 is a schematic diagram of the linearly reinforced elastic-plastic stress-strain curve of the steel wire rope material according to an embodiment of the present invention; Figure 4 is a schematic diagram of the load and axial displacement response curve of the steel wire rope under axial tension simulation according to an embodiment of the present invention; Figure 5 is a schematic diagram of the equivalent stress cloud map of the steel wire rope under different load levels during axial tension according to an embodiment of the present invention; Figure 6 is a schematic diagram of the equivalent plastic strain cloud map of the steel wire rope under different load levels during axial tension according to an embodiment of the present invention; Figure 7 is a schematic diagram of the assembly finite element model of the steel wire rope, the sleeve and the indenter according to an embodiment of the present invention; Figure 8 is a schematic diagram of the time-history load applied in the stamping analysis step and the tension analysis step according to an embodiment of the present invention; Figure 9 is a schematic diagram of the relationship curve between the tensile force and the longitudinal displacement of the steel wire rope in the tension analysis step according to an embodiment of the present invention; Figure 10 is a schematic diagram of the equivalent stress cloud map of the steel wire rope and the sleeve structure during the tension process according to an embodiment of the present invention. Detailed Implementation

[0021] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0022] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] This invention provides a nonlinear finite element analysis method for the crimping strength of steel wire ropes in electrical connectors. Taking a steel wire rope with a nominal diameter of 2mm used in a certain type of aviation electrical connector and its housing assembly as the analysis object, the implementation process of the method described in this invention is explained in detail. As shown in Figure 1, the method includes: Step S1: Establishing a geometric model and mesh generation of the steel wire rope. This step establishes a geometric model of the steel wire rope's winding state based on the actual structural characteristics of the steel wire rope, and performs mesh generation on the steel wire rope based on the geometric model to construct a finite element model of the steel wire rope. Specifically: First, based on the actual structural characteristics of the steel wire rope specified in GB / T9944-2015 standard, a geometric model of the steel wire rope's winding state is established; for example, the structural parameters of the steel wire rope are specified: the nominal diameter of the steel wire rope is 2mm, and the lay length is 7 times the rope diameter (14mm). The steel wire rope is composed of 7 strands of sub-steel wire rope wound together, and each sub-steel wire rope is composed of 7 strands of steel wire wound together, wherein the diameter of each steel wire is 0.22mm. Use the modeling module of 3D modeling software (such as SolidWorks) or finite element preprocessing software to create a geometric model of a 20mm long steel wire rope in its wound state. The key to modeling is to accurately represent the helical winding relationship of each strand of steel wire.

[0024] To effectively simulate the interaction between the wires in a wire rope, the circular cross-sections of the wires were separated during geometric modeling. A spacing was intentionally set between the circular cross-sections of each wire strand, ranging from 0.5% to 2% of the diameter of a single wire strand. In this embodiment, the spacing is set to 1% of the diameter of a single wire strand (i.e., 0.0022 mm). This spacing ensures that the wires do not interfere with each other, allowing for independent meshing of each sub-wire rope. Meshing the wire rope based on the geometric model effectively prevents element distortion during subsequent meshing and reserves space for defining the contact surface. This is an important preprocessing measure to ensure computational stability.

[0025] The geometric model is imported into finite element software (such as ABAQUS). The wire rope is meshed using eight-node reduced integral solid elements (C3D8R). To accurately calculate the contact stress between the wires, this embodiment of the invention applies Hertzian contact theory to guide local mesh refinement. Based on the wire material parameters and the estimated contact force F, the half-width of the contact surface between each wire is calculated using a formula. :

[0026] in, The contact surface width is half of the surface width. Contact force; The length of the line contact; and The coefficient of friction; and It is the elastic modulus; and The radius of a single strand of steel wire.

[0027] Subsequently, during mesh generation, local seed control is applied to the surface areas where contact may occur between the wires, ensuring that the minimum mesh size for the contact area between the wires is set to [value missing]. / 2 to / 3; For example, the grid size of the contact area along the contact normal is approximately / 2. For example, in this embodiment, the calculation is as follows: The mesh size is approximately 0.03 mm, so the mesh size for the contact area is set to 0.015 mm. For the non-contact areas and the axial direction of the wire, a relatively coarser mesh is used, such as 0.05 mm in the cross-sectional direction and 0.2 mm in the axial direction. This differentiated meshing strategy based on mechanical principles effectively controls the overall model size and improves computational efficiency while ensuring the calculation accuracy in critical areas. The final generated finite element model of the wire rope is shown in Figure 2.

[0028] Step S2: Define Material Properties and Contact Properties. This step defines the elastoplastic constitutive parameters and contact properties of the wire rope material.

[0029] Specifically, a linearly strengthened ideal elastoplastic model is used for the steel wire rope material to define its elastoplastic constitutive parameters. First, basic parameters are input: such as the density, elastic modulus (e.g., ~200 GPa), and Poisson's ratio (e.g., 0.3) of the steel wire rope material. Then, the elastoplastic constitutive parameters of the material are defined, including: initial yield stress. (Preset to 205 MPa), ultimate stress (Parameters to be calibrated) and the fracture strain corresponding to the ultimate stress (Based on material data, the value is taken as 0.4). This model implies that when the stress exceeds the initial yield stress... Subsequently, the material yields and begins to generate equivalent plastic strain, entering the plastic stage. The yield stress increases linearly with the plastic strain until the plastic strain reaches its maximum value. When the yield stress increases to The stress-strain relationship of the material is shown in Figure 3, which simulates the plastic flow of the material and keeps it constant.

[0030] Simultaneously, the contact properties between all the wires within the wire rope are defined. For example, the tangential behavior between the wires adopts a penalty function friction formula, with the contact friction coefficient set to 0.15; the normal behavior is defined as hard contact. This setting can reasonably simulate the friction and separation behavior between the wires.

[0031] Step S3: Axial Tension Simulation of Wire Rope. This step establishes the dynamic explicit calculation and analysis step for the axial tension of the wire rope. Boundary conditions are set at both ends of the wire rope to perform tensile numerical simulation, and the tensile force, tensile displacement, stress and strain results are output.

[0032] Create a dynamic explicit analysis step to simulate the axial tension of a wire rope. Set boundary conditions at both ends of the wire rope. In one embodiment, the boundary conditions include loads and boundary constraints at both ends of the wire rope; for example, constrain all degrees of freedom at one end of the wire rope and apply an axial displacement load at the other end to stretch the wire rope at a uniform speed.

[0033] After setting the boundary conditions, the tensile numerical simulation begins. Tension calculations are performed over time to obtain data on the reaction force (tensile force) and axial displacement (tensile displacement) during the tensile process, as shown in Figure 4. Simultaneously, equivalent stress and equivalent plastic strain distribution cloud maps for different load stages can be output. For example, during the wire rope tensioning process, the end tensile force reaches 0.1... 0.5 And 1.0 ( When the maximum tensile force is represented, the equivalent stress and equivalent plastic strain distribution characteristics of the structure are shown in Figures 5 and 6, respectively. Figure 6 clearly shows the process of plastic strain initiating from the contact point on the steel wire surface and gradually expanding.

[0034] Step S4: Iterative calibration of wire rope material parameters. This step iteratively calibrates the elastic-plastic constitutive parameters of the wire rope material based on the fracture strain and the minimum breaking tensile force index of the wire rope.

[0035] Specifically, the minimum breaking strength specified in the standard for this specification of wire rope is 0.3 tons (approximately 2942 N), and the material's fracture strain... The yield stress of the material is calibrated to 0.4. In the current tensile simulation, the applied tensile force increases linearly with time. If the simulated tensile force does not match 2942 N when the plastic strain reaches 0.4, it is necessary to return to step S2 and adjust the ultimate stress. The numerical value (for example, if the simulated force is too small, then increase) (Conversely, reduce), and then rerun step S3.

[0036] By repeatedly adjusting the ultimate stress Tensile simulations were performed using values ​​of , until the wire rope reached its fracture strain in the simulation. The deviation between the tensile force corresponding to the minimum breaking tensile force and the minimum breaking tensile force index is within a preset threshold. In this embodiment of the invention, the preset threshold is set to 5%. Specifically, after several iterations, this embodiment of the invention determines that when... When the tensile force was set to 3250 MPa, the simulation results showed that the maximum plastic strain of the structure reached exactly 0.4 when the tensile force reached 2943 N, with a deviation from the standard-specified breaking tensile force of only about 0.03%, far below the 5% engineering allowable error. This iterative calibration process enabled the constructed finite element model to accurately predict the overall tensile failure of the wire rope in the absence of detailed material test curves, laying a reliable material foundation for subsequent compression-tension coupling analysis.

[0037] Step S5: Establish and assemble the pressure head and casing models. This step establishes the geometric models of the casing and two opposing pressure heads and performs mesh generation. It constructs the finite element models of the casing and pressure heads, and completes the assembly of the finite element models of the casing and pressure heads with the finite element model of the wire rope.

[0038] Specifically, two opposing geometric models of the indenter and the casing are established. Based on the geometric symmetry of the actual parts, only half of the structural model is established to improve the efficiency of numerical calculations, as shown in Figure 7. The assembly structure consists of a wire rope, a casing, and an indenter. For example, the casing has a thickness of 1.25 mm, a length of 9 mm, a half-width of 4.35 mm, and an inner diameter of 2.2 mm; the indenter has a length of 9 mm and a width of 1.9 mm. The inner diameter of the casing is slightly larger than the diameter of the wire rope (2 mm in this embodiment), allowing the wire rope to be placed inside the casing. Both the indenter and the casing are meshed using C3D8R elements, with an element feature size of approximately 0.25 mm. To simplify the calculation, the material parameters of the casing are the same as those of the wire rope, employing a linearly strengthened ideal elastoplastic model. The indenter is defined as an analytical rigid body, and the friction coefficient between different components is set to 0.15. This completes the construction of the finite element models of the casing and the indenter.

[0039] Then, the finite element model of the wire rope, the finite element models of the two pressure heads, and the finite element model of the casing are positioned and assembled according to the actual assembly relationship, as shown in Figure 7. Note that the wire rope should be tightly attached to the inner wall of the casing's arc surface, and the two pressure heads should be symmetrically located on both sides of the casing's plane.

[0040] Step S6: Numerical Simulation of the Entire Stamping-Tensioning Process. This step adopts the dynamic explicit method, sequentially establishing the stamping analysis step and the tensile analysis step, defining the loads and boundary conditions of the press head, sleeve, and wire rope in the stamping analysis step and the tensile analysis step, completing the numerical simulation of the entire stamping-tensileing process, and outputting the simulation results.

[0041] Specifically, the explicit dynamic method is first used to establish two consecutive explicit dynamic analysis steps: a stamping analysis step and a tensile analysis step. The first analysis step (Step-1, stamping analysis step) simulates the stamping process, and for example, its duration is set to 1 second; the second analysis step (Step-2, tensile analysis step) simulates the tensile process, and for example, its duration is set to 0.05 seconds. Then, the loads and boundary conditions for the indenter, casing, and wire rope are defined in the two analysis steps, respectively.

[0042] In the stamping analysis step (Step-1): Displacement constraints are applied only to the two indenters, allowing them to move only in the direction perpendicular to the casing (Y direction). Equal and opposite vertical displacement loads (the loads in Analysis Step 1, represented by the black lines in Figure 8) are applied to the two indenters. For example, the maximum stamping force applied to each indenter is 1.25t, causing it to move towards the center of the casing. The maximum displacement brings the indenter into contact with the outer wall of the casing and clamps the wire rope. Simultaneously, the position of the casing in space is constrained. The curve of the stamping force changing with time is shown in the first segment of the black line in Figure 8, representing a linearly increasing stamping force.

[0043] In the tensile analysis step (Step-2): After stamping is completed (Step-1 end state), keep the pressure head position unchanged. Apply a concentrated axial (X-direction) load (specified tensile force) to one end of the wire rope. For example, the maximum tensile force is 0.175t. Apply a rigid fixed constraint to the end face of the casing on one side along the tensile direction. Based on symmetry, apply symmetrical displacement boundary conditions to the symmetry plane of the casing. The tensile force increases linearly from 0 to the maximum tensile force required by the product design (0.175 tons, approximately 1715N in this embodiment), as shown by the red line segment in Figure 8.

[0044] Finally, set the field variable output request to complete the numerical simulation of the entire stamping-stretching process and output the simulation results, including the indenter displacement, tensile force, tensile displacement, stress, strain, contact pressure and other results.

[0045] Step S7: Result Analysis and Strength Evaluation. This step involves post-processing analysis after the simulation calculation is completed. The crimping strength of the wire rope is evaluated based on the simulation results output in Step S6.

[0046] Specifically, according to product design requirements, the wire rope should not detach from the casing under a maximum tensile force of 0.175t. The simulation results were examined, and the relationship curve between the axial displacement of the wire rope and the applied tensile force was extracted, as shown in Figure 9. Simultaneously, the evolution of stress and strain contour maps of the wire rope and casing during the tensile process was observed, as shown in Figure 10.

[0047] If, when the tensile force reaches the maximum design value (1715 N), the simulation results show that: a) the wire rope is not detached from the casing; b) the maximum equivalent stress of the wire rope itself does not exceed its calibrated ultimate stress. (3250 MPa); then the crimping strength of the crimping structure is determined to meet the design requirements.

[0048] The simulation results of this embodiment satisfy all the above conditions. Figure 10 shows that the stress is mainly concentrated at the edge of the casing orifice and in the flattened wire rope area. The wire rope expands due to compression deformation at the left end of the casing. Under the combined action of compression deformation and the constraint of the casing, the inner and outer twists of the wire rope on the left side of the casing undergo relative movement, causing the outer twist to diffuse and eventually block at the left end of the casing, preventing further displacement of the leftmost end of the wire rope and forming an effective mechanical interlock that prevents it from being pulled out further. The calculation results show that the stamped casing can effectively hold the wire rope in place and prevent it from being completely pulled out. This visualization process clearly reveals the formation mechanism of the crimping strength, providing deeper information that cannot be provided by simple experiments.

[0049] Step S8: Process Parameter Optimization Analysis. Based on the calibrated material parameters and the established and verified finite element model, parametric studies can be easily conducted. For example, other conditions can be fixed while systematically changing parameters such as the final displacement of the indenter (controlling the degree of compression), the diameter of the inner hole of the casing or the taper of the inner wall (geometric dimensions), the stamping speed, and the stamping force. Then, steps S6 and S7 can be rerun to analyze the influence of these parameter changes on the final pressing strength (such as pull-out force). Through a small number of different parametric simulation calculations, a better combination of process parameters can be selected to guide actual production, achieving simulation-based design optimization to optimize the pressing process.

[0050] The method of this invention fully characterizes the three major nonlinear features of the compression-tension process by introducing an elasto-plastic material model, handling the geometric nonlinearity of large deformations, and defining complex contact interactions. The nonlinear load-displacement response curves shown in Figures 4 and 9, and the stress and strain nonuniform evolution contour maps shown in Figures 5 and 6, collectively demonstrate that this method can effectively simulate and reveal the nonlinear mechanical behavior throughout the entire process from linear elasticity and plastic yielding to large deformation. This achieves accurate prediction of the ultimate limit state of compression strength, overcoming the inherent defect of traditional linear elastic analysis in predicting structural failure.

[0051] In summary, the embodiments of the present invention provide a complete, precise, and reliable numerical analysis process for the crimping strength of steel wire ropes. This process can not only replace complex physical tests for strength verification, but also deeply reveal the failure mechanism and guide process optimization. It has important application value in the research and development of high-end equipment such as aviation electrical connectors.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A nonlinear finite element analysis method for the crimping strength of steel wire ropes in electrical connectors, characterized in that, Includes the following steps: S1. Based on the actual structural characteristics of the wire rope, establish a geometric model of the wire rope winding state, and based on the geometric model, mesh the wire rope to construct a finite element model of the wire rope. S2. Define the elastic-plastic constitutive parameters and contact properties of the wire rope material; S3. Establish a dynamic explicit calculation and analysis step for the axial tension of the wire rope, set the boundary conditions at both ends of the wire rope to perform tensile numerical simulation, and output the tensile force, tensile displacement, stress and strain results; S4. According to the fracture strain of the wire rope material and the minimum breaking tensile force index of the wire rope, perform iterative calibration of the elastic-plastic constitutive parameters. S5. Establish the geometric model of the casing and two opposing indenters and perform mesh generation. Construct the finite element model of the casing and the indenter, and assemble the finite element model of the casing and the indenter with the finite element model of the wire rope. S6. Using the dynamic explicit method, establish the stamping analysis step and the tensile analysis step in sequence. Define the loads and boundary conditions of the indenter, casing and wire rope in the stamping analysis step and the tensile analysis step. Complete the numerical simulation of the entire stamping-tensile process and output the simulation results. S7. Evaluate the crimping strength of the wire rope based on the simulation results.

2. The method according to claim 1, characterized in that, In step S1, when establishing the geometric model of the wire rope winding state, a spacing is set between the circular cross-sections of each wire strand, and the spacing is 0.5%-2% of the diameter of a single wire strand.

3. The method according to claim 1, characterized in that, In step S1, during mesh generation, the half-width of the contact surface between each steel wire is determined according to Hertzian contact theory. And set the minimum grid size of the contact area to / 2 to / 3。 4. The method according to claim 1, characterized in that, In step S2, the elastoplastic constitutive parameters are defined using a linearly strengthened ideal elastoplastic model, and the elastoplastic constitutive parameters include the initial yield stress. Ultimate stress and the fracture strain corresponding to the ultimate stress 。 5. The method according to claim 4, characterized in that, In step S4, the iterative calibration specifically involves repeatedly adjusting the limiting stress. The values ​​of [value] are used to perform tensile simulations until the steel wire rope reaches the aforementioned fracture strain in the simulation. The deviation between the tensile force corresponding to the minimum breaking tensile force and the minimum breaking tensile force index is within a preset threshold.

6. The method according to claim 5, characterized in that, The preset threshold is 5%.

7. The method according to claim 1, characterized in that, In step S6, during the stamping analysis step, opposing vertical displacement loads are applied to the two pressure heads; during the tensile analysis step, a specified tensile force is applied to one end of the wire rope, and a fixed constraint is applied to the end face of the casing on one side along the tensile direction.

8. The method according to claim 1, characterized in that, The method further includes step S8: based on the calibrated material parameters and the established finite element model, perform parametric simulations of different indenter displacements, punching forces, or casing geometry to optimize the pressing process.

9. The method according to claim 1, characterized in that, The finite element models of the wire rope, pressure head, and casing are all modeled using eight-node reduced integral solid elements.

10. The method according to claim 1, characterized in that, In step S7, if the simulation results show that the wire rope does not come out of the casing and the maximum equivalent stress does not exceed the material's ultimate stress under the specified tensile load, then the crimping strength is determined to meet the requirements.

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