A dynamic simulation method for profile welding process

Abstract

The application discloses a profile welding process dynamic simulation method, relates to the profile welding technical field, and comprises the following steps: establishing a three-dimensional model of a profile welding process; applying a magnetic field and a thermal field environment to the three-dimensional model and simulating and calculating a heating temperature field of the profile welding process; extracting the temperature of each node on the profile after heating is completed; based on the extracted temperature of each node after heating is completed, equivalent movement of the profile in the welding process is realized by using a dynamic pointer region assignment method, so that the dynamic simulation process of the welded profile is realized, and a relatively accurate temperature field is obtained. The application improves the method of replacing workpiece movement with heating time, the load migration method and other methods in the traditional welding simulation process, introduces welding influence temperature, avoids the movement assignment of all nodes, adopts the dynamic pointer grabbing mode to only grab and assign the key nodes of the welding influence temperature, reduces the operation amount in the simulation process, and reduces the operation time.

Description

Technical Field

[0001] This invention relates to the field of profile welding technology, and in particular to a dynamic simulation method for profile welding process. Background Technology

[0002] Profiles are objects with specific geometric shapes made of iron or steel, or materials with certain strength and toughness (such as plastics, aluminum, and fiberglass), through processes such as rolling, extrusion, and casting. Ordinary profiles can be classified according to their cross-sectional shape into I-beams, channel steel, angle steel, H-beams, and round steel. The welding process for profiles is a continuous motion welding process; therefore, the speed of the profiles during production is a crucial parameter. Thus, simulating the induction welding process of profiles requires considering not only the static simulation process but also the motion speed factor, constructing a dynamic simulation model for profile welding.

[0003] Currently, methods for simulating workpiece movement include using heating time to represent workpiece movement, heat source translation, and load transfer. However, using heating time to represent profile movement essentially treats the profile as stationary throughout the simulation, which is completely inconsistent with the actual welding process. Heat source translation and load transfer methods involve moving a coil, directly altering the relative position between the coil and the workpiece. For example, if the original distance between the coil and the workpiece at the welding V-angle was 30cm, it might become 20cm after heat source translation. In reality, the coil is fixed, while the workpiece moves, but the welding process continues, so the distance between the coil and the workpiece at the welding V-angle remains constant. Therefore, these methods also contradict reality. Because these methods are inconsistent with reality, the simulation results contain significant errors. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a dynamic simulation method for profile welding processes. By using a dynamic pointer region assignment method to represent the movement of the profile during the welding process, the dynamic simulation process of the welded profile is achieved, thereby obtaining a more accurate temperature field. This method can accurately, quickly, and effectively complete the dynamic simulation of the profile welding process.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A dynamic simulation method for profile welding process includes:

[0007] Establish a three-dimensional model of the profile welding process;

[0008] A magnetic field and a thermal field environment are applied to the three-dimensional model, and the heating temperature field of the profile welding process is simulated and calculated.

[0009] Extract the temperature T of each node on the profile after heating is completed. Mi ;

[0010] Regarding the temperature T after heating is complete Mi Less than the steady-state welding temperature T of the profile W And greater than the pointer movement activation temperature T Z The node is used to calculate the temperature T after heating is complete. Mi Compared to the temperature T before heating is complete Mi’ Temperature difference ΔT Mi =T Mi -T Mi’ And the temperature difference and the welding effect temperature T X Compare and capture ΔT Mi ≥T X The corresponding node temperatures T Mi The captured node temperature is assigned to the next adjacent node, so that the next node's temperature T before the next heating cycle is completed is set. M(i+1)’ The node temperature T after this heating is completed. Mi Then proceed to the next heating cycle.

[0011] Furthermore, regarding the temperature difference ΔT Mi Less than the welding influence temperature T X For each node, the static simulation process begins. It is then determined whether the current temperature field calculation has ended. If the current temperature field calculation has ended, the temperature of all nodes remains unchanged and the next heating cycle begins. If the current temperature field calculation has not ended, a time substep t = t + Δt is added, the temperature of all nodes remains unchanged, and the next heating cycle begins.

[0012] Furthermore, regarding the temperature T after heating is complete... Mi Less than T Z For each node, the static simulation process begins. It is then determined whether the current temperature field calculation has ended. If the current temperature field calculation has ended, the temperature of all nodes remains unchanged and the next heating cycle begins. If the current temperature field calculation has not ended, a time substep t = t + Δt is added, the temperature of all nodes remains unchanged, and the next heating cycle begins.

[0013] Furthermore, if the temperature after all nodes have been heated is greater than T... W Once the welding area of ​​the H-beam reaches the steady-state welding temperature, the simulation calculation is complete.

[0014] Furthermore, the profile is an H-beam, and a three-dimensional model of the steel profile welding process is established, including:

[0015] Determine the geometric dimensions of the H-beams, coils, and magnetic conductors required during the welding simulation process;

[0016] Based on the geometric dimensions of the H-beam, coil, and magnetic conductor, a geometric model of the H-beam, coil, and magnetic conductor is established in a 3D design software.

[0017] Import the established geometric model into the analysis software. After importation, activate the Cartesian coordinate system and complete the creation of the air model.

[0018] Furthermore, the coil is a rectangular spiral coil, and the magnetic conductor is inserted through the middle of the coil. The magnetic conductor is positioned directly opposite the weld seam, and the coil and the magnetic conductor are symmetrically distributed on both sides of the weld seam.

[0019] Furthermore, before applying the magnetic and thermal field environments to the three-dimensional model, the following steps are also included:

[0020] The geometric model is meshed;

[0021] The mesh of the weld seam area of ​​the profile is refined.

[0022] Furthermore, the mesh in the profile weld area is refined, including:

[0023] Refine the mesh for the welded V-corner section.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This invention employs a dynamic pointer region assignment method in the dynamic simulation of the profile welding process. During the simulation, the temperature of each node is continuously extracted and monitored. When the node temperature reaches the pointer movement activation temperature, the temperature data of the node affecting the welding temperature is dynamically captured and assigned to the next node until the temperature of all nodes in the welding area reaches the steady-state welding temperature. This completes the dynamic simulation of the profile welding process.

[0026] This invention introduces the influence of welding temperature, avoiding the need to assign values ​​to all nodes by moving them. It employs a dynamic pointer-based approach, capturing and assigning values ​​only to nodes whose temperature is affected by welding. Compared to traditional simulation methods that substitute heating time for billet movement or load migration, this achieves dynamic simulation of the welding process, conforming to actual welding conditions and improving the accuracy of the simulation results. Compared to existing node load movement methods (which simulate the movement of the welded pipe during welding by moving node loads), this method eliminates the need to ensure left-right symmetry of nodes at the welding V-angle or consistency of movement directions for all nodes. It has a wider range of applications, is suitable for various profiles, and has no requirements on workpiece shape. Furthermore, because it only captures and assigns values ​​to a subset of nodes, the calculation speed is faster and the efficiency is higher. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a finite element simulation flowchart of the heating process in an embodiment of the present invention;

[0029] Figure 2 This is a schematic diagram of the three-dimensional geometric model established in the embodiments of the present invention;

[0030] Figure 3 (1) is a front view of the grid division of the H-beam to be welded in an embodiment of the present invention;

[0031] Figure 3 (2) is a side view of the grid division of the H-beam to be welded in an embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram illustrating the principle of the dynamic pointer region assignment method in this embodiment of the invention;

[0033] Figure 5 This is an isotherm distribution diagram at a certain moment after heating is completed using the dynamic pointer region assignment method in this embodiment of the invention;

[0034] Figure 6 This is a temperature distribution cloud map of the weld direction section after the H-beam simulation in this embodiment of the invention;

[0035] In the attached diagram, 1-air model, 2-heating coil, 3-magnetic conductor, 4-H-beam. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] H-beams are an economical and efficient profile with a more optimized cross-sectional area distribution and a more reasonable strength-to-weight ratio. They are named for their cross-section resembling the letter "H". Because all parts of an H-beam are arranged at right angles, it possesses advantages such as high bending resistance in all directions, simple construction, cost savings, and lightweight structure, and has been widely used in the machinery and construction fields. The following section uses H-beams as an example to illustrate the dynamic simulation method for the welding process of profiles provided by this invention.

[0039] like Figure 1 As shown in the figure, a dynamic simulation method for profile welding process in an embodiment of the present invention includes the following steps:

[0040] Step 1: Establish a three-dimensional model of the H-beam welding process;

[0041] In practice, the H-beam model, coil model, and magnetic conductor model are constructed in Solidworks 3D design software based on the dimensional parameters of the H-beam. After saving them in the corresponding format, they are imported into ANSYS software. After importing, the Cartesian coordinate system is activated and the air model is created. The air model is 2 to 3 times the volume of the H-beam model.

[0042] The parameters used in the H-beam simulation process in this embodiment are shown in the following tables: Table 1 shows the parameters of the H-beam to be welded, Table 2 shows the current parameters during the H-beam welding process, and Table 3 shows the selection of initial parameters.

[0043] Table 1

[0044]

[0045] Table 2

[0046]

[0047] Table 3

[0048]

[0049]

[0050] like Figure 2 As shown, it illustrates a three-dimensional geometric model of the simulation process of the H-beam heating device. The heating coil 2 is a rectangular spiral coil, and a magnetic conductor 3 is inserted through the middle of the heating coil 2. The magnetic conductor 3 is positioned directly opposite the weld of the H-beam 4, so that the induced current can be targeted to the area to be heated. The heating coil 2 and the magnetic conductor 3 are symmetrically distributed on both sides of the weld of the H-beam 4.

[0051] Step 2: Select the element type, establish a file library of physical property parameters such as thermal conductivity k, specific heat capacity c, resistivity ρ and relative magnetic permeability μ of Q235 material, and perform meshing on the predefined geometric model and refine the mesh of the weld area of ​​H-beam steel.

[0052] like Figure 3 As shown in (1) and 3(2), the H-beam mesh division diagram during the heating simulation process is illustrated. The calculation process is related to the number of mesh divisions. The finer the mesh division, the more accurate the simulation results. However, the consequence of mesh refinement is an increase in calculation time. More seriously, it can directly cause the computer to crash and become unable to perform calculations. In order to ensure the accuracy of the simulation data and reduce the amount of calculation and save calculation time, only the particularly important parts are refined. The specific refinement method is to use a sweeping method to refine the mesh only on the welded V-corner part of the H-beam, without refining the mesh on the entire H-beam matrix. This invention mainly studies the simulated temperature field distribution at the weld position of the H-beam. Therefore, the weld position is divided into 3 layers of mesh units. The mesh division should gradually become sparse from the near end to the far end of the weld. At the same time, considering the application of the dynamic pointer region assignment method, the H-beam should be divided into uniformly sized unit meshes along the weld direction. After the mesh is divided, nodes will be formed. The number of nodes is directly related to the number of mesh divisions. Therefore, mesh refinement is also to make the node distance smaller, and such movement is closer to a continuous process.

[0053] Step 3: Apply the magnetic field and thermal field environments in the H-beam welding simulation to complete the temperature field simulation calculation and retrieve the temperature field calculation results;

[0054] The retrieved isotherm plot is as follows Figure 5 As shown.

[0055] The following uses the dynamic pointer region assignment method to represent the movement of H-beams during the welding process, such as... Figure 4As shown, this diagram illustrates the principle of the dynamic pointer region assignment method in this embodiment of the invention. Since the simulation process only involves capturing and reassigning the node temperature along the weld length direction, the coordinates of the temperature node along the weld thickness direction remain unchanged during the capture and reassignment process. Therefore, the node temperature T... Mi In this embodiment, M represents the row number of the temperature node, where M = A, B, C, D; and i represents the column number of the temperature node, where i = 1, 2, 3, ..., 9. Therefore, T A1 The value of can be represented as the temperature value of node A1.

[0056] Step 4: Extract the temperature T of each node on the H-beam after heating is complete. Mi The temperature T after each node is heated is... Mi Steady-state welding temperature T of H-beams W =Comparison at 1450℃: Due to T Mi <1450℃, therefore proceed directly to step 5;

[0057] Among them, the steady-state welding temperature of H-beams is the optimal welding temperature for Q235 materials, with an optimal temperature range of 1350℃~1500℃.

[0058] Step 5: After heating each node, set its temperature T. Mi Activation temperature T with pointer movement Z =760℃ for comparison: due to T B2 T B3 T C2 T C3 ≥760℃, therefore capture the temperatures of nodes B2, B3, C2, and C3, proceed to step 6, and keep the temperatures of the remaining nodes unchanged, proceed to step 7;

[0059] The pointer movement activation temperature is a user-defined activation temperature. In this embodiment, the Curie point temperature is set as the pointer movement activation temperature, specifically 760℃. During the welding heating process, the temperature rises rapidly before reaching the Curie point temperature, and then slows down after reaching the Curie point temperature. In this invention, the Curie point temperature is used as the pointer movement activation temperature. That is, when the temperature rise slows down, the system begins to search for key heating nodes with large temperature rises. A dynamic pointer region assignment method is implemented for these key heating nodes, reducing the amount of computation while ensuring the required accuracy.

[0060] Step 6: Calculate the temperature T of each captured node after heating is complete. Mi Compared to the temperature T before heating is complete Mi’ Temperature difference ΔT Mi =T Mi -T Mi’ And the temperature difference at each node and the welding influence temperature T X=Compare at 30℃: If ΔT Mi ≥T X Then capture ΔT Mi Temperatures T of all nodes corresponding to ≥30℃ Mi The captured node temperature is then assigned to the next adjacent node, ensuring that the next node's temperature T remains constant until the next heating cycle is complete. M(i+1)’ The node temperature T after this heating is completed. Mi Here we assume ΔT Mi ≥30℃, thus obtaining T B3’ =T B2 T B4’ =T B3 T C3’ =T C2 T C4’ =T C3 Then proceed to step 3 to continue heating;

[0061] If ΔT Mi <T X Then proceed to step 7;

[0062] Among them, the welding-affected temperature T X The selection of T is related to the computational efficiency and accuracy in the simulation process. The specific relationship between the two is shown in Table 4. In this embodiment, in order to improve the computational efficiency while ensuring the corresponding accuracy, T is chosen. X =30℃.

[0063] Table 4

[0064]

[0065]

[0066] Step 7: Enter the static simulation process and determine whether the current temperature field calculation process is complete. If the current temperature field calculation is complete, keep the temperature of all nodes constant, i.e., T. A1 =T A1’ T A2 =T A2’ …and proceed directly to step 3; if the temperature field calculation is not yet complete, add a time substep t = t + Δt, and proceed to step 4 after heating is complete;

[0067] In this context, the static simulation process refers to the process where node temperatures are not adjusted. Only nodes exceeding the specified criteria are moved. This approach reduces computation time and improves computational efficiency while maintaining accuracy.

[0068] The temperature field calculations are performed step-by-step through multiple iterations, with each iteration also completed in sub-steps of time. Δt represents a sub-step within the calculation time of each iteration. The end of the current temperature field calculation process refers to the gradual increase of the sub-steps of the current iteration until the heating time reaches the duration of the current iteration, thus completing the calculation of all times for the current iteration. For example, the heating time to reach a stable welding temperature is 1 minute. The heating process is to divide the 1 minute into 6 parts, each lasting 10 seconds, and heat each part 6 times (this is a cycle of dividing the 1 minute into 6 parts). Each of these 6 parts is further divided into a substep time Δt of 1 second (the substep time Δt can be arbitrary, but it must be less than the 10-second cycle time). After the 1-second heating is completed, the data is saved, and the method is used to determine whether node movement is necessary. If the temperature is not reached, all nodes remain stationary. Then, a substep time (i.e., an increase of 1 second) is added to the time of the previous second's temperature field and electromagnetic field. This continues until the heating time reaches 10 seconds, completing the calculation of the temperature field for this cycle. The next 10 seconds continues heating based on the previous 10 seconds, entering the second cycle, until all cycles are completed, thus completing the calculation of the entire temperature field.

[0069] Step 8: The welding area of ​​the H-beam reaches the steady-state welding temperature, i.e., T. Mi Simulation calculation completed at ≥1450℃.

[0070] like Figure 6 As shown, it illustrates the temperature distribution cloud map of the weld direction section after the simulation of the H-beam in an embodiment of the present invention. The temperature cloud map shows that the dynamic simulation of the H-beam under the dynamic pointer region assignment method ultimately made the area to be welded reach the steady-state welding temperature.

[0071] The present invention provides a dynamic simulation method for the induction welding process of H-beams, which improves the simulation accuracy by 37% compared to the traditional method of increasing the heating time to equivalent workpiece movement. The dynamic pointer region capture and reassignment method used in the present invention only captures and reassigns the temperature data of nodes affected by the welding temperature. Although the accuracy is reduced by 3.2% compared to all node movement calculation methods, the method provided by the present invention has a large reduction in calculation volume compared to the method of moving all nodes as a whole because the welding temperature is concentrated and the area is small. Therefore, the method provided by the present invention can reduce the calculation time by 63%.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dynamic simulation method for profile welding process, characterized in that, include: A three-dimensional model of the profile welding process is established; the profile is an H-beam; the coil is a rectangular spiral coil, and a magnetic conductor is inserted through the middle of the coil. The magnetic conductor is positioned directly opposite the weld seam, and the coil and the magnetic conductor are symmetrically distributed on both sides of the weld seam. A magnetic field and a thermal field environment are applied to the three-dimensional model, and the heating temperature field of the profile welding process is simulated and calculated. Extract the temperature T of each node on the profile after heating is completed. Mi ; Regarding the temperature T after heating is complete Mi Less than the steady-state welding temperature T of the profile W And greater than the pointer movement activation temperature T Z The node is used to calculate the temperature T after heating is complete. Mi Compared to the temperature T before heating is complete Mi’ Temperature difference ΔT Mi =T Mi -T Mi’ And the temperature difference and the welding effect temperature T X Compare and capture ΔT Mi ≥T X The corresponding node temperatures T Mi The captured node temperature is assigned to the next adjacent node, so that the next node's temperature T before the next heating cycle is completed is set. M（i+1）’ The node temperature T after this heating is completed. Mi And then proceed to the next heating cycle; Regarding the temperature difference ΔT Mi Less than the welding influence temperature T X For each node, the static simulation process begins. It is determined whether the current temperature field calculation has ended. If the current temperature field calculation has ended, the temperature of all nodes remains unchanged and the next heating cycle begins. If the current temperature field calculation has not ended, a time substep t = t + Δt is added, the temperature of all nodes remains unchanged, and the next heating cycle begins. Regarding the temperature T after heating is complete Mi Less than T Z For each node, the static simulation process begins. It is determined whether the current temperature field calculation has ended. If the current temperature field calculation has ended, the temperature of all nodes remains unchanged and the next heating cycle begins. If the current temperature field calculation has not ended, a time substep t = t + Δt is added, the temperature of all nodes remains unchanged, and the next heating cycle begins. If the temperature after all nodes have been heated is greater than T W Once the welding area of ​​the H-beam reaches the steady-state welding temperature, the simulation calculation is complete.

2. The dynamic simulation method for profile welding process according to claim 1, characterized in that, Establish a three-dimensional model of the steel profile welding process, including: Determine the geometric dimensions of the H-beams, coils, and magnetic conductors required during the welding simulation process; Based on the geometric dimensions of the H-beam, coil, and magnetic conductor, a geometric model of the H-beam, coil, and magnetic conductor is established in a 3D design software. Import the established geometric model into the analysis software. After importation, activate the Cartesian coordinate system and complete the creation of the air model.

3. The dynamic simulation method for profile welding process according to claim 2, characterized in that, Before applying the magnetic and thermal field environment to the three-dimensional model, the following steps are also included: The geometric model is meshed; The mesh of the profile weld area is refined.

4. The dynamic simulation method for profile welding process according to claim 3, characterized in that, The mesh of the profile weld area is refined, including: Refine the mesh for the welded V-corner section.

Images