A droplet heat source ring welding analysis method, device, equipment and medium

Abstract

The application discloses a kind of molten droplet heat source ring welding analysis method, device, equipment and medium, it is related to pipeline welding, metal micro-spray molten droplet drop, spread deposition forming additive manufacturing technical field, including obtaining material welding information, molten droplet heat source initial information, melt movement information, calculate melt flow information;Carry out ring welding model establishment, obtain pipeline ring welding three-dimensional model, carry out finite element mesh division, carry out simulation calculation, based on simulation calculation result constructs simulation weld area, compare simulation weld area with actual weld area, based on the result of comparison molten droplet heat source initial information and melt movement information update;The simulation weld area is updated, temperature field calculation, stress value calculation and forming topography evolution law summary are carried out, to realize the quality analysis and forming topography analysis of molten droplet heat source ring welding.Can determine the temperature field variation law after ring weld multi-pass welding in real time, effectively carry out process parameter adjustment, improve molten droplet heat source ring welding quality.

Description

Technical Field

[0001] This invention relates to the fields of pipeline welding, metal micro-spray molten droplet formation, and additive manufacturing technology, and particularly to a method, apparatus, equipment, and medium for analyzing circumferential welding using a molten droplet heat source. Background Technology

[0002] Compared to mainstream 3D printing technologies such as SLS, SLM, LCD, and EBM, additive manufacturing technologies involving pipe welding, metal micro-spraying molten droplet deposition, and spreading deposition modeling offer advantages such as lower equipment costs and readily available raw materials. They have broad application prospects in areas such as complex metal component fabrication, electronic packaging, and integrated structural and functional manufacturing. Metal micro-spraying molten droplet deposition technology involves heating and melting metal in a crucible using a resistance wire to form molten metal. A pressure is applied via a solenoid valve, causing the molten metal to be ejected from a nozzle. Under computer control, the uniformly sprayed metal droplets are precisely positioned on the heated substrate wall, accumulating point by point and layer by layer to form complex geometric shapes. To prevent metal oxidation, the entire device is under gas protection. Compared to rapid prototyping technologies such as lasers and electron beams, this technology does not require expensive equipment and offers advantages such as lower processing costs and higher precision parts, showing broad application prospects. However, the deformation of the metal micro-spraying droplets during the dripping and spreading process directly affects the forming and accuracy of the parts. Therefore, precise control of the morphological changes of the metal droplets during dripping and spreading is the key and challenging aspect of this process. However, due to the numerous factors influencing the morphology of the melt, the easy oxidation of the molten metal surface, high surface tension, and the difficulty in controlling the liquid viscosity (comparable to water), it differs significantly from the deposition molding of non-metallic materials. Therefore, current research is limited to molding simple-shaped parts, and there are still considerable difficulties in rationally selecting parameters; the molding design process lacks comprehensive theoretical guidance, resulting in low manufacturing precision and product quality.

[0003] As can be seen from the above, how to determine the temperature field data and flow morphology of the formed parts in the process of metal micro-spray molten droplet, spreading and deposition forming additive manufacturing, determine the temperature field change law after multi-pass welding of the circumferential weld in real time, effectively adjust the process parameters, and improve the circumferential welding quality of the molten droplet heat source are problems to be solved in this field. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a method, apparatus, equipment, and medium for analyzing circumferential welding using molten droplets, which can solve the problems of determining the temperature field data and flow morphology of formed parts in additive manufacturing processes involving the dripping, spreading, and deposition of molten metal micro-spraying. It can also determine the temperature field variation law of multi-pass welding of the circumferential weld in real time, effectively adjust process parameters, and improve the quality of circumferential welding using molten droplets. The specific solution is as follows:

[0005] In a first aspect, this application discloses a method for analyzing circumferential welding of molten droplet heat sources, including:

[0006] Obtain the material welding information, initial information of the droplet heat source, and melt movement information of the annular pipe material and welding wire material to be welded, as well as the material welding information, the initial information of the droplet heat source, and the melt movement information of the actual engineering site. Calculate the melt flow information based on the material welding information, the initial information of the droplet heat source, and the melt movement information.

[0007] Based on the circumferential welding analysis request of the molten droplet heat source, the initial information of the molten droplet heat source, and the melt flow information, a circumferential welding model is established to obtain a three-dimensional model of the pipe circumferential welding. The three-dimensional model of the pipe circumferential welding is then meshed using finite element methods to obtain the meshed three-dimensional model of the pipe circumferential welding.

[0008] A thermo-mass-fluid-structure interaction heat transfer simulation calculation is performed on the divided three-dimensional model of the pipe circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed, and the actual weld region output by the pipe circumferential welding experiment is obtained. The structural differences between the simulated weld region and the actual weld region are compared to obtain the comparison results. Based on the comparison results, the initial information of the molten droplet heat source and the molten motion information are updated to obtain the updated parameters of the simulated weld region.

[0009] The simulated weld region is updated using the updated parameters to obtain the updated simulated weld region. Temperature field calculation, stress value calculation, and formation morphology evolution law are then performed on the updated simulated weld region to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. Based on the temperature field distribution and residual stress value, the quality analysis of the droplet heat source ring weld is achieved, and based on the melt spreading morphology, the forming morphology analysis of the droplet heat source ring weld is achieved.

[0010] Optionally, obtain the request for molten droplet heat source ring welding quality analysis and the actual material welding information, initial information of the molten droplet heat source, and melt movement information of the ring pipe material to be welded at the engineering site, including:

[0011] Obtain material welding information of the actual annular pipe material and welding wire material to be welded at the engineering site, and use the droplet temperature, morphology and size, droplet frequency and jet angle determined by the welding process experiment as the initial information of the droplet heat source; wherein, the material welding information includes the basic thermophysical parameters of the material, the mechanical parameters of the material and the material welding structure information;

[0012] The point source position is determined based on the current number of welding torches, the distance between welding torches, and the start time. The position of the droplet formation point at the tip of the welding wire is taken as the point source position. Then, the process information of the melt moving from the point source position is taken as the melt movement information.

[0013] Optionally, calculating the melt flow information based on the material welding information, the initial information of the molten droplet heat source, and the melt motion information includes:

[0014] Based on the material welding information, the wire feeding speed and welding speed are determined. The volume of melt in contact with the annular weld per unit time is calculated using the wire feeding speed and welding speed to obtain a fixed flow rate value. The orientation of the point source is determined by the wire feeding angle.

[0015] Based on the melt motion information, the fixed flow rate value, and the orientation of the point source, the melt is made to flow and spread in the weld area to obtain a simulated weld bead layer. The melt flow information is determined based on the material welding information and the simulated weld bead layer.

[0016] Optionally, the finite element mesh generation of the three-dimensional model of the pipe circumferential weld includes:

[0017] The simulated weld bead layer is used as the first mesh generation rule, and the study of the temperature field distribution in the heat-affected zone is used as the second mesh generation rule.

[0018] The finite element mesh is generated for the three-dimensional model of the pipe circumferential welding based on the first mesh generation rule and the second mesh generation rule.

[0019] Optionally, the step of performing a heat transfer simulation calculation on the divided 3D model of the pipe circumferential weld to obtain the simulation results includes:

[0020] Based on the heat transfer phase change coupled fluid motion equation, energy transfer equation, preset density as a function of temperature, and mass transfer equation, the heat transfer simulation calculation between the molten metal and the weld bead of the divided three-dimensional model of the pipe ring weld is performed to obtain the simulation calculation results.

[0021] Optionally, the heat transfer simulation calculation between the molten metal and the weld bead is performed on the divided three-dimensional model of the pipe ring weld based on the heat transfer phase change coupled fluid motion equation, energy transfer equation, preset density as a function of temperature, and mass transfer equation, to obtain the simulation calculation results, including:

[0022] The heat transfer of the melt in the weld area is calculated based on Fourier's law, the flow and spreading effect of the melt in the weld area is calculated based on Navier-Stokes' equation, the energy transfer equation derived from the first law of thermodynamics, the function of density as a function of temperature, and the mass transfer equation. The thermal expansion and cooling rate of the material of the divided three-dimensional model of the pipe ring weld are simulated to obtain the simulation results.

[0023] Optionally, temperature field calculations, stress value calculations, and formation morphology evolution laws are performed on the updated simulated weld region to obtain the internal temperature field distribution, residual stress values, and melt propagation morphology of the metal material, including:

[0024] The parameters of the updated simulated weld area are extracted to obtain the extracted parameters. Based on the extracted parameters and combined with the energy transfer equation, the internal temperature data of the metal material is calculated to obtain the temperature field distribution inside the metal material.

[0025] Based on the extracted parameters and combined with the Mises yield criterion, the residual stress value inside the metal material is calculated to obtain the residual stress value inside the metal material.

[0026] Based on the extracted parameters, and combined with the fluid flow equation and energy transfer equation, the evolution of the weld bead formation morphology of the circumferential weld is calculated to obtain the melt spreading morphology used to characterize the evolution law of the multi-layer weld bead formation morphology.

[0027] Secondly, this application discloses a droplet heat source ring welding analysis device, comprising:

[0028] The request acquisition module is used to acquire the circumferential welding analysis request of the molten droplet heat source and the actual material welding information of the annular pipe material and welding wire material to be welded at the engineering site, the initial information of the molten droplet heat source, and the melt movement information. Based on the material welding information, the initial information of the molten droplet heat source, and the melt movement information, the melt flow information is calculated.

[0029] The ring welding model establishment module is used to establish a ring welding model based on the ring welding analysis request of the molten droplet heat source, the initial information of the molten droplet heat source, and the melt flow information to obtain a three-dimensional ring welding model of the pipeline. The three-dimensional ring welding model of the pipeline is then divided into finite element meshes to obtain the divided three-dimensional ring welding model of the pipeline.

[0030] The simulation calculation module is used to perform heat transfer simulation calculations on the divided three-dimensional model of the pipe circumferential welding to obtain simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed, the actual weld region output by the pipe circumferential welding experiment is obtained, the structural differences between the simulated weld region and the actual weld region are compared to obtain comparison results, and the initial information of the molten droplet heat source and the molten motion information are updated based on the comparison results to obtain the updated parameters of the simulated weld region.

[0031] The circumferential welding analysis module is used to update the simulated weld region using the updated parameters of the simulated weld region to obtain the updated simulated weld region. It then performs temperature field calculations, stress value calculations, and summarizes the evolution law of the forming morphology of the updated simulated weld region to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. Based on the temperature field distribution and the residual stress value, it performs quality analysis of the circumferential welding of the molten droplet heat source, and based on the melt spreading morphology, it performs forming morphology analysis of the circumferential welding of the molten droplet heat source.

[0032] Thirdly, this application discloses an electronic device, including:

[0033] Memory, used to store computer programs;

[0034] A processor is used to execute the computer program to implement the aforementioned method for analyzing circumferential welding of molten droplet heat sources.

[0035] Fourthly, this application discloses a computer storage medium for storing a computer program; wherein, when the computer program is executed by a processor, it implements the steps of the aforementioned disclosed method for analyzing circumferential welding of molten droplet heat sources.

[0036] As can be seen, this application provides a method for analyzing circumferential welding using molten droplet heat sources. This method includes acquiring material welding information, initial information of the molten droplet heat source, and melt motion information of the annular pipe material and welding wire material to be welded, as well as the actual information from the engineering site, based on the circumferential welding analysis request, the initial information of the molten droplet heat source, and the melt motion information. Based on these information, melt flow information is calculated. A circumferential welding model is established based on the circumferential welding analysis request, the initial information of the molten droplet heat source, and the melt flow information to obtain a three-dimensional model of the pipe circumferential welding. The three-dimensional model of the pipe circumferential welding is then meshed using finite element methods to obtain a meshed three-dimensional model of the pipe circumferential welding. A heat-mass-fluid-structure interaction (HTSH) simulation calculation is performed on the meshed three-dimensional model of the pipe circumferential welding to obtain simulation results. Based on the simulation results, a simulated welding model is constructed. The simulated weld area is obtained from the actual weld area output by the pipe circumferential welding experiment. The structural differences between the simulated weld area and the actual weld area are compared to obtain the comparison results. Based on the comparison results, the initial information of the molten droplet heat source and the melt movement information are updated to obtain the simulation weld area update parameters. The simulation weld area is updated using the simulation weld area update parameters to obtain the updated simulation weld area. Temperature field calculation, stress value calculation, and formation morphology evolution law are performed on the updated simulation weld area to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. The quality analysis of the circumferential welding of the molten droplet heat source is realized based on the temperature field distribution and the residual stress value, and the forming morphology analysis of the circumferential welding of the molten droplet heat source is realized based on the melt spreading morphology. This application establishes a ring welding model through molten droplet heat source ring welding analysis, then meshes the model, performs heat transfer simulation calculations based on thermal-fluid-structure interaction, compares structural differences based on the simulation results to update the initial information of the molten droplet heat source, and then calculates stress values ​​to obtain the residual stress values ​​inside the metal material. This enables quality analysis of molten droplet heat source ring welding. This application can solve the problems of determining the temperature field data and flow morphology of the formed parts in metal micro-spray molten droplet, spreading deposition forming additive manufacturing, and can determine the temperature field change law of the ring weld after multi-pass welding in real time, effectively adjust process parameters, and improve the quality of molten droplet heat source ring welding. Attached Figure Description

[0037] 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 only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0038] Figure 1This application discloses a flowchart of a circumferential welding analysis method using a molten droplet heat source.

[0039] Figure 2 This application discloses a flowchart of a circumferential welding analysis method using a molten droplet heat source.

[0040] Figure 3 This is a simulation system diagram of a circumferential welding analysis method for molten droplet heat sources disclosed in this application;

[0041] Figure 4 This is a structural diagram of another circumferential welding analysis device for molten droplet heat source disclosed in this application;

[0042] Figure 5 This is a schematic diagram of the structure of a droplet heat source ring welding analysis device disclosed in this application;

[0043] Figure 6 This application provides a structural diagram of an electronic device. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 are within the scope of protection of the present invention.

[0045] Compared to mainstream 3D printing technologies such as SLS, SLM, LCD, and EBM, additive manufacturing technologies involving pipe welding, metal micro-spraying molten droplet deposition, and spreading deposition modeling offer advantages such as lower equipment costs and readily available raw materials. They have broad application prospects in areas such as complex metal component fabrication, electronic packaging, and integrated structural and functional manufacturing. Metal micro-spraying molten droplet deposition technology involves heating and melting metal in a crucible using a resistance wire to form molten metal. A pressure is applied via a solenoid valve, causing the molten metal to be ejected from a nozzle. Under computer control, the uniformly sprayed metal droplets are precisely positioned on the heated substrate wall, accumulating point by point and layer by layer to form complex geometric shapes. To prevent metal oxidation, the entire device is under gas protection. Compared to rapid prototyping technologies such as lasers and electron beams, this technology does not require expensive equipment and offers advantages such as lower processing costs and higher precision parts, showing broad application prospects. However, the deformation of the metal micro-spraying droplets during the dripping and spreading process directly affects the forming and accuracy of the parts. Therefore, precise control of the morphological changes of the metal droplets during dripping and spreading is the key and challenging aspect of this process. However, due to the numerous factors influencing melt morphology, the molten metal surface's susceptibility to oxidation, high surface tension, and the difficulty in controlling its viscosity (comparable to water), it differs significantly from non-metallic material deposition molding. Therefore, current research focuses on forming simple-shaped parts, with considerable challenges in rationally selecting parameters. Furthermore, the lack of comprehensive theoretical guidance for forming design processes results in low manufacturing precision and product quality. As such, determining the temperature field data and flow morphology of formed parts in metal micro-spray melt dripping and spreading deposition additive manufacturing, as well as real-time determination of temperature field changes after multi-pass welding of circumferential welds, and effective adjustment of process parameters to improve the quality of circumferential welding using molten droplet heat sources, are problems that need to be solved in this field.

[0046] See Figure 1 As shown in the figure, this invention discloses a method for analyzing circumferential welding of molten droplet heat sources, which may specifically include:

[0047] Step S11: Obtain the material welding information, initial information of the droplet heat source, and melt movement information of the annular pipe material and welding wire material to be welded in the actual engineering site, as well as the droplet heat source initial information and melt movement information. Calculate the melt flow information based on the material welding information, the droplet heat source initial information, and the melt movement information.

[0048] In this embodiment, the actual material welding information of the annular pipe material and welding wire material to be welded at the engineering site is obtained. The droplet temperature, morphology and size, droplet frequency and jet angle determined by the welding process experiment are used as the initial information of the droplet heat source. The material welding information includes the basic thermophysical parameters, mechanical parameters and welding structure information of the material. The point source position is determined based on the current number of welding torches, welding torch spacing and start time. The position of the droplet formation position at the front end of the welding wire is used as the point source position. Then, the process information of the melt moving from the point source position is used as the melt movement information. Then, the wire feeding speed and welding speed are determined based on the material welding information. The volume of melt in contact with the annular weld per unit time is calculated using the wire feeding speed and welding speed to obtain a fixed flow rate value. The orientation of the point source is determined by the wire feeding angle. The melt flows and spreads in the weld area according to the melt movement information, the fixed flow rate value and the orientation of the point source to obtain a simulated weld layer. The melt flow information is determined based on the material welding information and the simulated weld layer. Specifically, the heat transfer and phase change spreading behavior of the melt are calculated based on the equations of motion and energy transfer of incompressible fluids (i.e., flow spreading). The energy of the high-temperature melt is conducted to the welding area and distributed in the form of temperature, forming the real-time temperature distribution of the formed part during the welding process.

[0049] The basic thermophysical parameters of the annular pipe material may include melt viscosity, heat capacity, thermal conductivity, coefficient of thermal expansion, latent heat of fusion, solidus temperature, liquidus temperature, point source size, melt temperature, melt flow rate, melt surface tension coefficient, and melt contact angle. Material mechanical parameters may include material density and material type. Welding structure information may include the spatial position of the welding materials, welding type (overhead, vertical, flat), point source location, melt ejection angle, bevel type, preheating time, gap, and plate thickness. The target formed part is manufactured in the experiment; the structural information of the formed part is the final morphology of the multi-layer weld bead after the molten droplet solidifies.

[0050] In the simulation, the wire diameter can be compared to the point source diameter, and the wire feed speed can be calculated with the wire diameter to obtain the melt flow rate ejected into the weld area per unit time; this flow rate value serves as the initial setting of the point source. Since the fluid-structure interaction effect varies at different welding positions in the circumferential weld, it is necessary to adjust the point source ejection angle according to the welding position, the point source ejection position according to the preset weld layer height, and the point source ejection flow rate according to the preset weld layer width. The point source movement time and angular velocity at a fixed distance are calculated based on the welding linear velocity, and the welding linear velocity is decomposed into a two-dimensional function with varying welding angular velocity, welding time, and welding linear velocity. When the melt is ejected from the point source and comes into contact with the circumferential weld area at room temperature, it flows and spreads under the influence of gravity. The melt viscosity increases as the temperature decreases, and the fluidity deteriorates. As the melt temperature drops below the liquidus, the melt undergoes a phase change and gradually solidifies, bonding with the weld area.

[0051] Specifically, the process of determining the material welding information and initial information of the droplet heat source for the annular pipe to be welded based on the droplet heat source ring welding analysis request and business requirements is as follows: The number of point sources, their positions, and their movement speeds are determined based on the number of welding torches, the distance between the welding torches, and the start-up time; the welding speeds for different weld passes are determined based on experimental information, and velocity decomposition is performed with the distance between the point source position and the origin position as the radius to obtain the XYZ direction velocity components that change with time; the volume of melt flowing into the weld area per unit time is calculated using the wire feed speed based on experimental information; the size information at the outlet of the droplet heat source is determined using the welding wire diameter; and the angular velocity of the droplet heat source is calculated by combining the welding speed with the size information of the workpiece.

[0052] Step S12: Based on the circumferential welding analysis request of the molten droplet heat source, the initial information of the molten droplet heat source, and the melt flow information, establish a circumferential welding model to obtain a three-dimensional model of the pipe circumferential welding. Perform finite element mesh generation on the three-dimensional model of the pipe circumferential welding to obtain the meshed three-dimensional model of the pipe circumferential welding.

[0053] In this embodiment, based on the dynamic adjustment of experimental parameters for welding at different positions of the circumferential weld, the established three-dimensional model of the circumferential weld with molten droplet heat source is divided into regions. Based on flat welding, vertical welding, and overhead welding, the following areas are selected counterclockwise: 40-60 degrees from the 12 o'clock to 6 o'clock position for flat welding, 80-100 degrees for vertical welding, and 120-140 degrees for overhead welding. The point source flow rate and ejection direction are adjusted according to the magnitude of the influence of gravity on the melt at different welding positions. The three-dimensional model of the circumferential weld with molten droplet heat source is decomposed into the weld region, heat-affected zone, and base material region, and finite element meshes are generated according to their computational focus. Thermal-fluid-structure interaction (FSH) simulation calculations are performed on the divided three-dimensional model to simulate the temperature field changes of the weldment during welding with molten droplets as the heat source, obtaining the temperature field distribution pattern of the weldment under fluid-structure heat transfer after the melt flows out of the moving source.

[0054] The 3D model for circumferential welding using a droplet heat source consists of the weld region, the heat-affected zone (HAZ), and the base material. The calculation focuses on the flow and spreading of the melt within the weld region, while the HAZ focuses on heat transfer through contact between the high-temperature melt emitted from the point source and the weld region. The temperature field distribution within the HAZ is studied. Therefore, based on the calculation priorities, the weld region and HAZ models are meshed with higher precision, while the base material region, farther from the HAZ, uses a mesh with slightly lower precision. Since the mesh and 3D model are not correlated, they can be freely modified. The 3D model for circumferential welding using a droplet heat source is established as follows: both the pipe model and the melt are set to a fluid state, with the pipe at room temperature and the melt at a temperature above the liquidus line of the model material; thus, they exhibit completely different phase states. The influence of various thermophysical parameters, either as constant values ​​or as temperature functions, on the rheological phenomena and heat transfer process of the droplets in the weld is analyzed.

[0055] This application also includes: embedding the geometry into a rectangular computational mesh and setting reasonable boundary conditions for constraint; refining the solidification process of the melt after spreading in the key computational area of ​​the weld seam of the model to be welded, and using a larger mesh size for the heat transfer calculation of the part of the pipe away from the weld seam compared to the fine mesh at the weld seam; the model remains fixed in the computational area, so the boundary conditions are selected as initialized symmetrical boundaries. In addition, the weld layer of this application is stacked layer by layer. When the point source moves repeatedly, the weld layer is stacked layer by layer, filling the entire weld seam to form a complete welding area. During this process, heat transfer and phase change occur.

[0056] High-temperature molten metal is ejected from a point source at a fixed angle and flow rate. The ejection angle needs to be adjusted experimentally depending on the welding location. Upon contact with the weld area, heat conduction occurs. Under the influence of gravity, the molten metal flows along the weld in the direction of gravity. During this flow, heat is transferred to the heat-affected zone and the base metal. Limited by viscosity, surface tension, and temperature, the molten metal gradually cools during heat transfer. Upon reaching the liquidus, it undergoes a phase change and solidifies. Influenced by viscosity, surface tension, and the coefficient of thermal expansion, the solidified molten metal forms a shaped weld bead with regular ripples.

[0057] Step S13: Perform heat transfer simulation calculations on the divided 3D model of the pipe circumferential welding to obtain simulation results. Based on the simulation results, construct a simulated weld region, obtain the actual weld region output by the pipe circumferential welding experiment, compare the structural differences between the simulated weld region and the actual weld region to obtain comparison results, and update the initial information of the molten droplet heat source and the melt motion information based on the comparison results to obtain the updated parameters of the simulated weld region.

[0058] In this embodiment, the formed part (i.e., the target weld area) that meets the welding process and welding requirements is compared with the test piece (i.e., the historical weld area). The melt flows into the weld area for contact heat transfer and spreads along the weld area, forming a weld area with a certain weld width and depth. A comprehensive evaluation is performed using weld dimensions, melt spread shape, and layered data. The differentiated information is summarized to adjust the welding process parameters, model material information, and dimensional information in the simulation to meet the welding result requirements of the test piece. In other words, by comparing the information of the weld area (i.e., the target weld area) that has already completed multi-layer weld spread and formation with the formed part (i.e., the historical weld area), the dimensional information of weld depth, weld width, and weld reinforcement during the weld spread process can be determined based on the comparison results. Based on the comparison results, determine whether adjustments to the simulated pre-set thermophysical and mechanical parameters are necessary. If within the error range, minor adjustments can be made to the pre-set parameters to better match the expected melt spread. If outside the error range, analyze the existing melt spread and dynamically adjust the pre-set material thermophysical parameters and point source parameters to meet reasonable weld bead formation requirements. Specific dynamic adjustments include: comparing weld depth, width, and weld reinforcement with experimental values ​​for different welding types; evaluating the continuity of single-layer weld bead formation to ensure a complete, continuous, and smoothly transitioning weld bead shape under various welding conditions.

[0059] Step S14: Update the simulated weld region using the updated parameters to obtain the updated simulated weld region. Perform temperature field calculation, stress value calculation, and summarize the evolution law of the forming morphology on the updated simulated weld region to obtain the temperature field distribution, residual stress value, and melt spreading morphology inside the metal material. Based on the temperature field distribution and the residual stress value, perform quality analysis on the circumferential welding of the molten droplet heat source. Based on the melt spreading morphology, perform forming morphology analysis on the circumferential welding of the molten droplet heat source.

[0060] In this embodiment, the specific process for temperature field calculation, stress value calculation, and the summary of the evolution law of the forming morphology is as follows: Parameters are extracted from the updated simulated weld area to obtain extracted parameters; based on the extracted parameters and combined with the energy transfer equation, the internal temperature data of the metal material is calculated to obtain the internal temperature field distribution of the metal material; based on the extracted parameters and combined with the Mises yield criterion, the internal residual stress value of the metal material is calculated to obtain the internal residual stress value of the metal material; based on the extracted parameters and combined with the fluid flow equation and energy transfer equation, the evolution of the forming morphology of the circumferential weld bead is calculated to obtain the melt spreading morphology used to characterize the evolution law of the forming morphology of the multi-layer weld bead.

[0061] During fusion welding, the molten metal ejected from the point source carries extremely high energy and acts on a localized area of ​​the workpiece. The instant the molten metal contacts the base material, the energy is transferred internally via heat conduction, creating a temperature gradient between the weld zone, heat-affected zone, and base material. As the point source moves and the molten metal flows along the weld direction to other areas, the temperature in those areas drops rapidly. The heat transfer occurring at various points on the weldment due to the flow and spread of the molten metal causes instantaneous changes in temperature distribution. Furthermore, the uneven temperature field introduced during welding alters the internal microstructure and mechanical properties of the welded material. This application decomposes the welding speed into two dimensions along the plane of motion on a macroscopic scale, analogizing the point source to the tip of the welding wire. The point source moves along the weld area and flows into it with a preset flow rate of high-temperature molten metal to complete the weld bead formation and temperature field data calculation. The influence of gravitational acceleration is used as the decisive factor for the direction and flow rate of the molten metal ejected from the point source. Taking the decomposition of the welding linear velocity in the experiment into two-dimensional directional velocity in the simulation to simulate the circumferential velocity as an important breakthrough, this application systematically studies the dynamic changes and temperature changes of the molten metal in contact with the weld area during the welding process, with the molten droplet as the heat source, and the flow and spreading of the molten metal to form the weld bead on a macroscopic scale. It accurately describes the dynamic change mechanism of the molten metal flow and spreading during weld bead formation, providing a solid theoretical basis for determining the heat-affected zone, temperature data, and crystal changes near the weld. Based on the determined temperature data, the crystal types in the weld-heat-affected zone-base metal and the residual stress of the weld can be determined, which can improve the strength grade and welding quality of the circumferential weld.

[0062] On a macroscopic scale, the welding speed is decomposed into two dimensions along the plane of motion, with the point source analogous to the tip of the welding wire. This can include: calculating the melt ejection flow rate of the point source; decomposing the point source's motion speed into two dimensions; and setting the point source diameter and ejection direction. Specifically, based on experimental conditions, the volume of melt flowing into the weld area per unit time can be calculated by combining the selected welding wire diameter with the wire feed speed and welding speed. The point source is analogous to the tip of the welding wire; in the experiment, the heat source heats and melts the tip of the welding wire, forming a high-temperature melt that drips into the weld area. In the simulation, the point source diameter is the welding wire diameter, and the ejection flow rate is the volume of melt flowing into the weld area per unit time calculated in the experiment. Different welding positions require different welding parameters in the experiment, and these also need to be adjusted accordingly in the simulation. Compared to vertical welding, flat welding has a smaller welding angle and is less difficult, while overhead welding is more difficult. All three welding methods require adjustments to the welding current, welding voltage, and welding heat input to achieve suitable welding results. Effects: In the simulation, the ejection angle of the point source needs to be adjusted to match the wire feed angle in the experiment, so that the melt can contact the weld area at a suitable speed and undergo heat transfer phase change behavior under the influence of gravity after being ejected from the point source. When calculating the vertical welding position (80-100°) of the annular pipe, since the welding direction is from top to bottom, the position of the point source at the welding start point should be perpendicular to the weld area or slightly upward. This ensures that the melt will not tilt in the ejection direction or fall before contacting the weld area due to gravity when it is ejected from the point source during welding. For overhead welding (120-140°), the point source needs to be in the center of the weld area, and the ejection angle should be kept vertically upward or slightly offset by 5-10°. The gravity of the molten metal will hinder the transfer of the molten droplets, and the molten pool metal will also fall due to its own gravity. The higher the temperature, the lower the surface tension of the molten pool. Therefore, it is necessary to adjust the ejection speed and ejection angle of the point source as well as the spatial position of the point source to obtain a better formed weld.

[0063] The dynamic changes and temperature variations of the molten metal in contact with the weld area during heat transfer and its flow and formation can be summarized as follows: the molten metal is ejected from a point source at a fixed angle, temperature, and flow rate into the weld area. Under the movement of the point source, the molten metal within the weld undergoes a heat transfer phase change during its flow, ultimately forming a complete weld layer. Specifically, a model of the pipe circumferential weld-heat-affected zone-base metal region is constructed, and a finite element mesh is generated for the three-dimensional model. The mesh refinement is adjusted based on the computational focus. When the molten metal is ejected from the point source and contacts the weld area, heat diffuses to the weld area, heat-affected zone, and base metal region through thermal conduction. A distinct temperature field distribution is formed. According to the Navier-Stokes equations, under the influence of gravity, the melt flows along the weld area. Limited by surface tension, viscosity, and coefficient of thermal expansion, the flow effect of the molten metal decreases as it gradually cools. When the melt temperature cools below the liquidus line, the melt undergoes a phase change and combines with the weld area to form a complete weld bead area. The point source moves in uniform circular motion along the center of the weld area. Therefore, the welding speed needs to be decomposed in two dimensions to make it a function of welding linear velocity, welding angular velocity, and time. As time changes, the motion of the point source will change from linear motion to approximately circular motion to complete the formation of the circumferential weld bead.

[0064] Finally, based on the determined temperature data, the crystal types within the weld, heat-affected zone, and base material are identified, and the residual stress of welding is calculated. This improves the strength grade and welding quality of the circumferential weld. Specifically, after acquiring the temperature field data of the circumferential weld after multi-pass welding, the residual stress value inside the metal material can be calculated based on the temperature field value at a fixed position at a specific instant, using the extraction of thermal cycle parameters and the Mises yield criterion. This enables quality analysis of the circumferential weld against the molten droplet heat source. The specific quality analysis of the circumferential weld against the molten droplet heat source involves calculating and analyzing the temperature field distribution and heat transfer laws of the weld area, heat-affected zone, and base material. This includes: initial temperature field data of the pipe circumferential weld area and temperature field changes during the flow and spreading of a single-layer weld, interlayer heat dissipation, and temperature field changes in the circumferential weld area after multi-layer weld stacking; calculation of continuous temperature changes and complex thermal history resulting from single-gun or double-gun welding.

[0065] This application obtains the dimensions and structural information of the pipeline and welding bevel from the engineering site, as well as the basic thermophysical and mechanical parameters of the base material and welding material. Based on welding process experiments, it determines the temperature, morphology, size, droplet frequency, and jet angle of the molten droplets. A digital twin model of the circumferential welding process is established, and a molten droplet heat source is set up to characterize the actual high-temperature welding droplets. The initial and motion information of the molten droplet heat source are determined according to the experimental data to obtain a three-dimensional model of the pipeline circumferential welding. The three-dimensional model of the pipeline circumferential welding is then meshed using finite element methods. The thermo-mass-fluid-structure interaction heat transfer simulation calculation is performed on the meshed three-dimensional model of the pipeline circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, a simulated weld area is constructed, and the actual weld area output from the pipeline circumferential welding experiment is obtained. The structural differences between the simulated weld area and the actual weld area are compared to obtain the comparison results. If the comparison result is greater than 10% (taking 10% as an example), the physical parameters of the model (i.e., the initial information of the molten droplet heat source and the motion information of the melt) are updated until the difference is less than 10%. Based on the verified 3D model of pipeline circumferential welding, temperature field calculation, residual stress calculation, and morphological evolution law of pipeline circumferential weld area under various working conditions can be performed. This enables structural and quality analysis of pipeline circumferential welding, and allows for real-time determination of temperature field and residual stress changes after multi-pass welding of circumferential weld, enabling effective adjustment of process parameters and improvement of pipeline circumferential welding quality.

[0066] In this embodiment, the material welding information, initial information of the molten droplet heat source, and melt motion information of the annular pipe material and welding wire material to be welded, as well as the material welding information, initial information of the molten droplet heat source, and melt motion information, are obtained from the molten droplet heat source circumferential welding analysis request and the actual material of the annular pipe material and welding wire material at the engineering site. Based on the material welding information, the initial information of the molten droplet heat source, and the melt motion information, melt flow information is calculated. A circumferential welding model is established based on the molten droplet heat source circumferential welding analysis request, the initial information of the molten droplet heat source, and the melt flow information to obtain a three-dimensional model of the pipe circumferential welding. The three-dimensional model of the pipe circumferential welding is then meshed using finite element methods to obtain the meshed three-dimensional model of the pipe circumferential welding. A heat-mass-fluid-structure interaction (HTFS) simulation calculation is performed on the meshed three-dimensional model of the pipe circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed to obtain the pipe circumferential weld area. The actual weld area output from the welding experiment is compared with the simulated weld area to obtain a comparison result. Based on the comparison result, the initial information of the molten droplet heat source and the melt movement information are updated to obtain the simulation weld area update parameters. The simulation weld area is updated using the simulation weld area update parameters to obtain the updated simulation weld area. Temperature field calculation, stress value calculation, and formation morphology evolution law are performed on the updated simulation weld area to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. Based on the temperature field distribution and residual stress value, the quality analysis of the circumferential welding of the molten droplet heat source is realized. Based on the melt spreading morphology, the forming morphology analysis of the circumferential welding of the molten droplet heat source is realized. This application establishes a ring welding model through molten droplet heat source ring welding analysis, then meshes the model, performs heat transfer simulation calculations based on thermal-fluid-structure interaction, compares structural differences based on the simulation results to update the initial information of the molten droplet heat source, and then calculates stress values ​​to obtain the residual stress values ​​inside the metal material. This enables quality analysis of molten droplet heat source ring welding. This application can solve the problems of determining the temperature field data and flow morphology of the formed parts in metal micro-spray molten droplet, spreading deposition forming additive manufacturing, and can determine the temperature field change law of the ring weld after multi-pass welding in real time, effectively adjust process parameters, and improve the quality of molten droplet heat source ring welding.

[0067] See Figure 2 As shown in the figure, this invention discloses a method for analyzing circumferential welding of molten droplet heat sources, which may specifically include:

[0068] Step S21: Obtain the material welding information, initial information of the droplet heat source, and melt movement information of the annular pipe material and welding wire material to be welded, as well as the material welding information, the initial information of the droplet heat source, and the melt movement information of the actual engineering site. Calculate the melt flow information based on the material welding information, the initial information of the droplet heat source, and the melt movement information.

[0069] Step S22: Based on the circumferential welding analysis request of the molten droplet heat source, the initial information of the molten droplet heat source, and the melt flow information, a circumferential welding model is established to obtain a three-dimensional model of the pipe circumferential welding. The simulated weld layer is used as the first mesh generation rule, and the study of the temperature field distribution of the heat-affected zone is used as the second mesh generation rule. Based on the first mesh generation rule and the second mesh generation rule, the three-dimensional model of the pipe circumferential welding is meshed using finite element methods to obtain the meshed three-dimensional model of the pipe circumferential welding.

[0070] Step S23: Based on the heat transfer phase change coupled fluid motion equation, energy transfer equation, preset density-temperature change function, and mass transfer equation, perform heat-fluid-structure interaction heat transfer simulation calculation between the molten metal and the weld bead on the divided three-dimensional model of the pipe circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, construct the simulated weld region, obtain the actual weld region output by the pipe circumferential welding experiment, compare the structural differences between the simulated weld region and the actual weld region to obtain the comparison results, and update the initial information of the molten droplet heat source and the molten metal motion information based on the comparison results to obtain the updated parameters of the simulated weld region.

[0071] In this embodiment, the specific process of the heat transfer simulation calculation of the thermal-fluid-structure interaction is as follows: The heat transferred by the melt in the weld area is calculated according to Fourier's law; the flow and spreading effect of the melt in the weld area is calculated according to the Navier-Stokes equations; the material thermal expansion and cooling rate of the divided three-dimensional model of the pipe ring weld are simulated and calculated according to the energy transfer equation derived from the first law of thermodynamics, the density-temperature function, and the mass transfer equation, to obtain the simulation results. Specifically, the Navier-Stokes equations are used to calculate the fluid dynamics changes of the molten metal as it flows out from the heat source and spreads in contact with the weld area; the structural temperature equation is used to calculate the temperature field data during the heat transfer phase transition of the molten metal; and the flow rate of the point source melt is controlled according to the mesh size.

[0072] The heat transfer of the melt within the weld region is calculated using Fourier's law. The solidification morphology of the melt in the weld is predicted based on changes in surface tension coefficient, melt viscosity, and coefficient of thermal expansion, thus obtaining a reasonable melt depth and width. The flow and spreading effect of the melt within the weld region is calculated using Navier-Stokes equations. When calculating the heat transfer and fluid flow effects in the molten pool, factors such as the geometry of the molten pool, temperature gradient, local cooling rate, and solidification structure are considered. The energy transfer equation derived from the first law of thermodynamics and the function of density versus temperature are used to assess the energy transfer effect of the melt phase transformation process within the weld region, thereby obtaining a reasonable melt depth and width and determining a reasonable spreading morphology of the melt after phase transformation.

[0073] Step S24: Update the simulated weld region using the updated parameters to obtain the updated simulated weld region. Perform temperature field calculation, stress value calculation, and summarize the evolution law of the forming morphology on the updated simulated weld region to obtain the temperature field distribution, residual stress value, and melt spreading morphology inside the metal material. Based on the temperature field distribution and the residual stress value, perform quality analysis on the circumferential welding of the molten droplet heat source. Based on the melt spreading morphology, perform forming morphology analysis on the circumferential welding of the molten droplet heat source.

[0074] The circumferential welding analysis and simulation system for the molten droplet heat source in this application is as follows: Figure 3As shown, Step 1: Establish a suitable circumferential weld area model based on the known material to be welded, bevel type, and plate thickness; determine the number of weld layers, welding method, and number of welding torches based on the bevel type and size; preset the basic physical property parameters of the model, including material density, coefficient of thermal expansion, heat capacity, thermal conductivity, liquidus temperature, solidus temperature, ambient temperature, latent heat of fusion, surface tension coefficient, and melt viscosity; after the preset parameters are completed, calculate the volume of melt flowing into the weld area per unit time based on the number of weld layers, weld layer height, and weld layer depth; determine the point source position based on the height of a single weld layer, and select the appropriate point source position and melt ejection direction for root welding, hot welding, fill welding, and capping welding; use dual-torch welding. During single-gun welding, the weld bead formation work needs to be carried out at fixed intervals, one in front of the other. In single-gun welding, the welding line velocity is used to perform two-dimensional planar decomposition to transform the point source's uniform linear motion into uniform circular motion. A suitable ejection angle and the flow rate obtained from the weld depth and width calculated based on the target weld bead size are selected. The point source moves around the weld area and inputs molten material at a fixed flow rate and temperature. In dual-gun welding, it is necessary to ensure that the molten material from the later-starting point source does not interfere with weld bead formation. This requires using a single point source to weld a weld bead length equivalent to the distance maintained during dual-gun operation, and then continuing with both point sources. The front point source starts moving from the position where the previous point source has already completed welding, while the rear point source starts moving from its initial position. Welding is performed, and the welding simulation at this time is the formation of a double-gun circumferential weld bead; Step 2: Unit mesh generation. To save computing resources, three arc-shaped circumferential weld-heat affected zone-base material models at positions of 40-60°, 80-100°, and 120-140° are selected in the 180° pipe model as welding models for flat welding, vertical welding, and overhead welding; According to the calculation focus, the weld area-heat affected zone-base material area are all divided into three-dimensional models using high-precision meshes; symmetrical boundary conditions are selected at the boundaries; Step 3: After the melt is ejected from the point source, it flows towards the weld area under the action of gravity, and heat is transferred in the form of heat conduction after contacting the weld area; Under the action of surface tension and viscosity, the high-temperature melt flows as the temperature decreases. As the fluidity gradually deteriorates, surface tension causes the melt to contract inward, resulting in a weld layer shape that is wider at the sides and slightly higher in the middle. Fluid motion calculations are performed using Navier-Stokes equations, and heat transfer is performed using Fourier's law and energy transfer equations. A significant temperature gradient is formed between the weld area, the heat-affected zone, and the base material area. Due to the existence of the temperature gradient, the model undergoes micro-deformations of varying sizes due to thermal expansion. Under the influence of uneven heating and cooling processes, the internal model elements expand and contract. The elements detect changes in the internal fluid volume, calculate the temperature field changes and model volume changes at a certain instant during the heat transfer phase transition, and then calculate the changes in the internal stress field of the material and the residual stress field distribution in the annular pipe calculation area after cooling to room temperature.Step 4: The point source, analogous to the tip of the welding wire, provides melt to the weld area. As the point source moves in a uniform circular motion along the weld area, the melt also completes its flow and spreading. After the point source circulates, the multi-layer weld bead formation at the bevel of the annular pipe is completed. The single-layer weld bead formation effect is compared with the corresponding weld bead height, width, and formation effect of the test piece, and the preset parameters are adjusted according to the differences. Based on the distribution pattern of the welding temperature field, the thermal cycle data of the fixed point within a certain time range is calculated. The thermal history of the fixed position of the model during the point source circulation is analyzed by plotting the thermal cycle number. The range of the heat-affected zone is determined based on the calculated temperature data. The thermal expansion and cooling rate of the heat-affected zone model material are calculated based on the temperature gradient, Fourier's law, the law of conservation of energy, and the energy transfer formula. The residual stress value inside the model is calculated in combination with the Mises yield criterion to achieve microscopic quality control of welding. Based on the extracted parameters, and combined with the fluid flow equation and energy transfer equation, the evolution of the circumferential weld bead formation morphology is calculated to obtain a characterization of the multi-layer weld bead. The melting morphology evolution law of the formed shape; Step 5: Post-processing the three-dimensional model to form a complete multi-pass welding model temperature field distribution and three-dimensional forming effect under point source cyclic motion; The model completes the overall welding work using root welding, hot welding, fill welding and cover welding as welding methods, and records the thermal history and thermal cycle data of fixed points during different weld processes; In the two-dimensional slice data, it is calculated whether there are defects inside the formed weld of the model, whether the melt height and melt width are consistent with the test object, and the two-dimensional temperature field distribution and temperature gradient are visualized. The molten droplet maintains the upper limit temperature in the simulation. After contacting the weld area at room temperature, it forms a temperature cloud map with obvious temperature gradient; In the one-dimensional temperature data calculation, the thermal history of the fixed point during multi-pass welding, i.e., the temperature change history, can be known; The three-dimensional model results give the final effect of multi-pass weld formation in the simulation, the two-dimensional model results directly and obviously visualize the planar temperature gradient, and the one-dimensional results clearly show the temperature change trend of the fixed point temperature over time.

[0075] In another embodiment, the molten droplet heat source ring welding analysis device can be further divided into the following modules, such as... Figure 4As shown: The parameter adjustment and conversion module is used to determine the circumferential velocity of the point source, the melt flow velocity, and the point source diameter in the simulation of the temperature field of the circumferential weld formation of the droplet heat source; the droplet heat source and point source information communication module is used to calculate and adjust the position information of the droplet heat source and the melt motion information with the flow rate, temperature, and ejection direction; the model calculation area selection module is used to obtain a suitable model area with obvious setting differences to simulate the weld bead formation law under flat welding, vertical welding, and overhead welding; the weld bead structure information determination module is used to obtain the forming height, width, interlayer cooling time, and target structure of different weld layers; the process parameter adjustment module is used to visualize the model that has completed the single-layer weld bead spreading and calculate the temperature data, and adjust the preset parameters based on the existence of defects and abnormal temperature data.

[0076] Specifically, the process parameter acquisition module acquires preset process parameters for the pre-welding of circumferential welds using molten droplets as a heat source, including material thermophysical parameters, mechanical parameters, and basic property parameters. The molten droplet heat source parameter determination module sets the point source ejection angle, point source size, ejection flow rate, and motion angular velocity according to welding process requirements and welding position requirements to ensure that the molten material makes uniform circular motion around the pipe center, maximizing contact between the molten material and the weld area. The calculation focus and typical calculation location selection module prioritizes the weld area and the heat-affected zone, with the weld area being the focus of the calculation. This calculation focuses on the formation effect of multi-layer weld beads and the flow and spreading effect of the melt. The heat-affected zone (HAZ) calculation emphasizes the heat transfer from the weld area to the HAZ and base metal areas via thermal conduction. Typical welding positions are calculated by using pipe models with different angle ranges in the simulation as the initial welding models for flat, vertical, and overhead welding positions. The point source motion velocity decomposition module decomposes the welding linear velocity present in the experiment into a two-dimensional equation along the point source motion plane, making it a function of welding linear velocity, welding angular velocity, and time, thus addressing the rotational speed issue in the simulation where an angular velocity setting module is not available. The module includes a temperature data statistics and monitoring module. After repeatedly performing multiple weld bead formations around different weld areas using a point source, the 3D model image displays the complete forming state and overall temperature distribution. Two-dimensional slicing of the model clearly calculates the temperature gradient and temperature field distribution within a fixed slice area, from the weld area to the heat-affected zone to the base material. When the temperature monitoring point is positioned at a fixed distance from the weld, the one-dimensional temperature data reflects the complete thermal history of the welding process. The data comparison and reverse adjustment module compares the formed part with the test piece, analyzing the 3D forming effect, 2D temperature distribution, and 1D thermal history. Based on the differences, it reverse-adjusts the preset parameters or the fineness of the calculation mesh. It adjusts the selection of the welding calculation position, the point source movement position, and the decomposition density of the velocity to more closely approximate circular motion. Based on the corrected simulation parameters and settings, a comparison is made again to obtain a high-precision, well-formed droplet heat source ring weld formation calculation result.

[0077] In this embodiment, the material welding information, initial information of the molten droplet heat source, and melt motion information of the annular pipe material and welding wire material to be welded, as well as the material welding information, initial information of the molten droplet heat source, and melt motion information, are obtained from the molten droplet heat source circumferential welding analysis request and the actual material of the annular pipe material and welding wire material at the engineering site. Based on the material welding information, the initial information of the molten droplet heat source, and the melt motion information, melt flow information is calculated. A circumferential welding model is established based on the molten droplet heat source circumferential welding analysis request, the initial information of the molten droplet heat source, and the melt flow information to obtain a three-dimensional model of the pipe circumferential welding. The three-dimensional model of the pipe circumferential welding is then meshed using finite element methods to obtain the meshed three-dimensional model of the pipe circumferential welding. A heat-mass-fluid-structure interaction (HTFS) simulation calculation is performed on the meshed three-dimensional model of the pipe circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed to obtain the pipe circumferential weld area. The actual weld area output from the welding experiment is compared with the simulated weld area to obtain a comparison result. Based on the comparison result, the initial information of the molten droplet heat source and the melt movement information are updated to obtain the simulation weld area update parameters. The simulation weld area is updated using the simulation weld area update parameters to obtain the updated simulation weld area. Temperature field calculation, stress value calculation, and formation morphology evolution law are performed on the updated simulation weld area to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. Based on the temperature field distribution and residual stress value, the quality analysis of the circumferential welding of the molten droplet heat source is realized. Based on the melt spreading morphology, the forming morphology analysis of the circumferential welding of the molten droplet heat source is realized. This application establishes a ring welding model through molten droplet heat source ring welding analysis, then meshes the model, performs heat transfer simulation calculations based on thermal-fluid-structure interaction, compares structural differences based on the simulation results to update the initial information of the molten droplet heat source, and then calculates stress values ​​to obtain the residual stress values ​​inside the metal material. This enables quality analysis of molten droplet heat source ring welding. This application can solve the problems of determining the temperature field data and flow morphology of the formed parts in metal micro-spray molten droplet, spreading deposition forming additive manufacturing, and can determine the temperature field change law of the ring weld after multi-pass welding in real time, effectively adjust process parameters, and improve the quality of molten droplet heat source ring welding.

[0078] See Figure 5 As shown, this embodiment of the invention discloses a circumferential welding analysis device using a molten droplet heat source, which may specifically include:

[0079] The request acquisition module 11 is used to acquire the molten droplet heat source ring welding analysis request and the actual material welding information, molten droplet heat source initial information and melt movement information of the ring pipe material and welding wire material to be welded at the engineering site, and to calculate the melt flow information based on the material welding information, the molten droplet heat source initial information and the melt movement information.

[0080] The ring welding model establishment module 12 is used to establish a ring welding model based on the ring welding analysis request of the molten droplet heat source, the initial information of the molten droplet heat source and the melt flow information, so as to obtain a three-dimensional model of the pipe ring welding, and to perform finite element meshing on the three-dimensional model of the pipe ring welding to obtain the meshed three-dimensional model of the pipe ring welding.

[0081] The simulation calculation module 13 is used to perform heat-mass-fluid-structure interaction heat transfer simulation calculation on the divided three-dimensional model of the pipe circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed, the actual weld region output by the pipe circumferential welding experiment is obtained, the structural difference between the simulated weld region and the actual weld region is compared to obtain the comparison results, and the initial information of the molten droplet heat source and the molten motion information are updated based on the comparison results to obtain the updated parameters of the simulated weld region.

[0082] The circumferential welding quality analysis module 14 is used to update the simulated weld region using the updated parameters of the simulated weld region to obtain the updated simulated weld region. The module performs temperature field calculation, stress value calculation, and summarizes the evolution law of the forming morphology of the updated simulated weld region to obtain the temperature field distribution, residual stress value, and melt spreading morphology inside the metal material. Based on the temperature field distribution and the residual stress value, the module performs quality analysis of the circumferential welding of the molten droplet heat source. Based on the melt spreading morphology, the module performs forming morphology analysis of the circumferential welding of the molten droplet heat source.

[0083] In this embodiment, the material welding information, initial information of the molten droplet heat source, and melt motion information of the annular pipe material and welding wire material to be welded, as well as the material welding information, initial information of the molten droplet heat source, and melt motion information, are obtained from the molten droplet heat source circumferential welding analysis request and the actual material of the annular pipe material and welding wire material at the engineering site. Based on the material welding information, the initial information of the molten droplet heat source, and the melt motion information, melt flow information is calculated. A circumferential welding model is established based on the molten droplet heat source circumferential welding analysis request, the initial information of the molten droplet heat source, and the melt flow information to obtain a three-dimensional model of the pipe circumferential welding. The three-dimensional model of the pipe circumferential welding is then meshed using finite element methods to obtain the meshed three-dimensional model of the pipe circumferential welding. A heat-mass-fluid-structure interaction (HTFS) simulation calculation is performed on the meshed three-dimensional model of the pipe circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed to obtain the pipe circumferential weld area. The actual weld area output from the welding experiment is compared with the simulated weld area to obtain a comparison result. Based on the comparison result, the initial information of the molten droplet heat source and the melt movement information are updated to obtain the simulation weld area update parameters. The simulation weld area is updated using the simulation weld area update parameters to obtain the updated simulation weld area. Temperature field calculation, stress value calculation, and formation morphology evolution law are performed on the updated simulation weld area to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. Based on the temperature field distribution and residual stress value, the quality analysis of the circumferential welding of the molten droplet heat source is realized. Based on the melt spreading morphology, the forming morphology analysis of the circumferential welding of the molten droplet heat source is realized. This application establishes a ring welding model through molten droplet heat source ring welding analysis, then meshes the model, performs heat transfer simulation calculations based on thermal-fluid-structure interaction, compares structural differences based on the simulation results to update the initial information of the molten droplet heat source, and then calculates stress values ​​to obtain the residual stress values ​​inside the metal material. This enables quality analysis of molten droplet heat source ring welding. This application can solve the problems of determining the temperature field data and flow morphology of the formed parts in metal micro-spray molten droplet, spreading deposition forming additive manufacturing, and can determine the temperature field change law of the ring weld after multi-pass welding in real time, effectively adjust process parameters, and improve the quality of molten droplet heat source ring welding.

[0084] In some specific embodiments, the request acquisition module 11 may specifically include:

[0085] The information acquisition module is used to acquire the actual material welding information of the annular pipe material and welding wire material to be welded at the engineering site. The molten droplet temperature, morphology and size, droplet frequency and jet angle determined by the welding process experiment are used as the initial information of the molten droplet heat source. The material welding information includes the basic thermophysical parameters of the material, the mechanical parameters of the material and the material welding structure information.

[0086] The melt motion information determination module is used to determine the point source position based on the current number of welding torches, welding torch spacing, and start-up time. The position of the droplet formation point at the tip of the welding wire is taken as the point source position, and then the process information of the melt moving from the point source position is taken as the melt motion information.

[0087] In some specific embodiments, the request acquisition module 11 may specifically include:

[0088] The fixed flow rate value determination module is used to determine the wire feeding speed and welding speed based on the material welding information, calculate the volume of melt in contact with the annular weld per unit time using the wire feeding speed and the welding speed to obtain a fixed flow rate value, and determine the orientation of the point source by the wire feeding angle.

[0089] The melt flow information determination module is used to realize the flow and spread of melt in the weld area according to the melt motion information, the fixed flow rate value and the orientation of the point source to obtain a simulated weld layer, and to determine the melt flow information based on the material welding information and the simulated weld layer.

[0090] In some specific embodiments, the ring welding model establishment module 12 may specifically include:

[0091] The mesh generation rule determination module is used to use the simulated weld layer as the first mesh generation rule and the study of the temperature field distribution of the heat-affected zone as the second mesh generation rule.

[0092] The finite element mesh generation module is used to perform finite element mesh generation on the three-dimensional model of the pipe circumferential welding based on the first mesh generation rule and the second mesh generation rule.

[0093] In some specific embodiments, the simulation calculation module 13 may specifically include:

[0094] The thermal-fluid-structure interaction heat transfer simulation module is used to perform thermal-fluid-structure interaction heat transfer simulation calculations between the molten metal and the weld bead on the divided three-dimensional model of the pipe ring weld based on the heat transfer phase change coupled fluid motion equation, energy transfer equation, preset density change function with temperature, and mass transfer equation, so as to obtain simulation calculation results.

[0095] In some specific embodiments, the simulation calculation module 13 may specifically include:

[0096] The simulation calculation result determination module is used to calculate the heat transfer of the melt in the weld area according to Fourier's law, calculate the flow and spreading effect of the melt in the weld area according to Navier-Stokes equations, and perform simulation calculations on the material thermal expansion and cooling rate of the divided three-dimensional model of the pipe ring weld according to the energy transfer equation derived from the first law of thermodynamics, the function of density changing with temperature, and the mass transfer equation, so as to obtain the simulation calculation results.

[0097] In some specific embodiments, the circumferential welding quality analysis module 14 may specifically include:

[0098] The parameter extraction module is used to extract parameters from the updated simulated weld area to obtain the extracted parameters. Based on the extracted parameters and combined with the energy transfer equation, the internal temperature data of the metal material is calculated to obtain the temperature field distribution inside the metal material.

[0099] The calculation module is used to calculate the residual stress value inside the metal material based on the extracted parameters and in combination with the Mises yield criterion, so as to obtain the residual stress value inside the metal material.

[0100] The melt spreading morphology determination module is used to calculate the evolution of the weld bead forming morphology of the circumferential weld bead based on the extracted parameters and in combination with the fluid flow equation and energy transfer equation, so as to obtain the melt spreading morphology used to characterize the evolution law of the forming morphology of the multi-layer weld bead.

[0101] Figure 6 This is a schematic diagram of an electronic device provided in an embodiment of this application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. The memory 22 stores a computer program, which is loaded and executed by the processor 21 to implement the relevant steps in the droplet heat source circumferential welding analysis method performed by the electronic device as disclosed in any of the foregoing embodiments.

[0102] In this embodiment, the power supply 23 is used to provide operating voltage for each hardware device on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and external devices, and the communication protocol it follows can be any communication protocol applicable to the technical solution of this application, and is not specifically limited here; the input / output interface 25 is used to acquire external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs, and is not specifically limited here.

[0103] In addition, the memory 22, as a carrier for resource storage, can be a read-only memory, random access memory, disk or optical disk, etc. The resources stored on it include operating system 221, computer program 222 and data 223, etc., and the storage method can be temporary storage or permanent storage.

[0104] The operating system 221 manages and controls the various hardware devices on the electronic device 20 and the computer program 222 to enable the processor 21 to perform calculations and processing on the data 223 in the memory 22. The operating system can be Windows, Unix, Linux, etc. The computer program 222, in addition to including a computer program capable of performing the droplet heat source ring welding analysis method executed by the electronic device 20 as disclosed in any of the foregoing embodiments, may further include computer programs capable of performing other specific tasks. The data 223 may include data received by the droplet heat source ring welding analysis device from external devices, as well as data collected by its own input / output interface 25.

[0105] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0106] Furthermore, this application also discloses a computer-readable storage medium storing a computer program. When the computer program is loaded and executed by a processor, it implements the steps of the droplet heat source ring welding analysis method disclosed in any of the foregoing embodiments.

[0107] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0108] The above provides a detailed description of the circumferential welding analysis method, apparatus, equipment, and storage medium for molten droplet heat sources provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for analyzing circumferential welding of molten droplet heat sources, characterized in that, include: Obtain the material welding information, initial information of the droplet heat source, and melt movement information of the annular pipe material and welding wire material to be welded, as well as the material welding information, the initial information of the droplet heat source, and the melt movement information of the actual engineering site. Calculate the melt flow information based on the material welding information, the initial information of the droplet heat source, and the melt movement information. Based on the circumferential welding analysis request of the molten droplet heat source, the initial information of the molten droplet heat source, and the melt flow information, a circumferential welding model is established to obtain a three-dimensional model of the pipe circumferential welding. The three-dimensional model of the pipe circumferential welding is then meshed using finite element methods to obtain the meshed three-dimensional model of the pipe circumferential welding. A thermo-mass-fluid-structure interaction heat transfer simulation calculation is performed on the divided three-dimensional model of the pipe circumferential welding to obtain the simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed, and the actual weld region output by the pipe circumferential welding experiment is obtained. The structural differences between the simulated weld region and the actual weld region are compared to obtain the comparison results. Based on the comparison results, the initial information of the molten droplet heat source and the molten motion information are updated to obtain the updated parameters of the simulated weld region. The simulated weld region is updated using the updated parameters to obtain the updated simulated weld region. Temperature field calculation, stress value calculation, and formation morphology evolution law are then performed on the updated simulated weld region to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. Based on the temperature field distribution and residual stress value, the quality analysis of the droplet heat source ring weld is achieved, and based on the melt spreading morphology, the forming morphology analysis of the droplet heat source ring weld is achieved.

2. The method for analyzing circumferential welding of molten droplet heat sources according to claim 1, characterized in that, Obtain the request for molten droplet heat source ring welding quality analysis and the actual material welding information, initial information of the molten droplet heat source, and melt movement information of the ring pipe material to be welded at the engineering site, including: Obtain material welding information of the actual annular pipe material and welding wire material to be welded at the engineering site, and use the droplet temperature, morphology and size, droplet frequency and jet angle determined by the welding process experiment as the initial information of the droplet heat source; wherein, the material welding information includes the basic thermophysical parameters of the material, the mechanical parameters of the material and the material welding structure information; The point source position is determined based on the current number of welding torches, the distance between welding torches, and the start time. The position of the droplet formation point at the tip of the welding wire is taken as the point source position. Then, the process information of the melt moving from the point source position is taken as the melt movement information.

3. The method for analyzing circumferential welding of molten droplet heat sources according to claim 1, characterized in that, The calculation of melt flow information based on the material welding information, the initial information of the molten droplet heat source, and the melt motion information includes: Based on the material welding information, the wire feeding speed and welding speed are determined. The volume of melt in contact with the annular weld per unit time is calculated using the wire feeding speed and welding speed to obtain a fixed flow rate value. The orientation of the point source is determined by the wire feeding angle. Based on the melt motion information, the fixed flow rate value, and the orientation of the point source, the melt is made to flow and spread in the weld area to obtain a simulated weld bead layer. The melt flow information is determined based on the material welding information and the simulated weld bead layer.

4. The method for analyzing circumferential welding of molten droplet heat sources according to claim 1, characterized in that, The finite element mesh generation of the three-dimensional model of the pipe circumferential welding includes: The simulated weld bead layer is used as the first mesh generation rule, and the study of the temperature field distribution in the heat-affected zone is used as the second mesh generation rule. The finite element mesh is generated for the three-dimensional model of the pipe circumferential welding based on the first mesh generation rule and the second mesh generation rule.

5. The method for analyzing circumferential welding of molten droplet heat sources according to claim 1, characterized in that, The process involves performing a thermal-mass-fluid-structure interaction (TMS) simulation on the divided 3D model of the pipe circumferential weld to obtain simulation results, including: Based on the heat transfer phase change coupled fluid motion equation, energy transfer equation, preset density as a function of temperature, and mass transfer equation, the heat transfer simulation calculation between the molten metal and the weld bead of the divided three-dimensional model of the pipe ring weld is performed to obtain the simulation calculation results.

6. The method for analyzing circumferential welding of molten droplet heat sources according to claim 5, characterized in that, The heat transfer, phase change coupled fluid motion equation, energy transfer equation, preset density versus temperature function, and mass transfer equation are used to perform heat transfer simulation calculations on the divided 3D model of the pipe circumferential weld between the molten metal and the weld bead, so as to obtain simulation results, including: The heat transfer of the melt in the weld area is calculated based on Fourier's law, the flow and spreading effect of the melt in the weld area is calculated based on Navier-Stokes' equation, the energy transfer equation derived from the first law of thermodynamics, the function of density as a function of temperature, and the mass transfer equation. The thermal expansion and cooling rate of the material of the divided three-dimensional model of the pipe ring weld are simulated to obtain the simulation results.

7. The method for analyzing circumferential welding of molten droplet heat sources according to any one of claims 1 to 6, characterized in that, The updated simulated weld region is subjected to temperature field calculations, stress value calculations, and a summary of the evolution law of its forming morphology, in order to obtain the internal temperature field distribution, residual stress value, and melt propagation morphology of the metal material, including: The parameters of the updated simulated weld area are extracted to obtain the extracted parameters. Based on the extracted parameters and combined with the energy transfer equation, the internal temperature data of the metal material is calculated to obtain the temperature field distribution inside the metal material. Based on the extracted parameters and combined with the Mises yield criterion, the residual stress value inside the metal material is calculated to obtain the residual stress value inside the metal material. Based on the extracted parameters, and combined with the fluid flow equation and energy transfer equation, the evolution of the weld bead formation morphology of the circumferential weld is calculated to obtain the melt spreading morphology used to characterize the evolution law of the multi-layer weld bead formation morphology.

8. A circumferential welding analysis device for molten droplet heat source, characterized in that, include: The request acquisition module is used to acquire the circumferential welding analysis request of the molten droplet heat source and the actual material welding information of the annular pipe material and welding wire material to be welded at the engineering site, the initial information of the molten droplet heat source, and the melt movement information. Based on the material welding information, the initial information of the molten droplet heat source, and the melt movement information, the melt flow information is calculated. The ring welding model establishment module is used to establish a ring welding model based on the ring welding analysis request of the molten droplet heat source, the initial information of the molten droplet heat source, and the melt flow information to obtain a three-dimensional ring welding model of the pipeline. The three-dimensional ring welding model of the pipeline is then divided into finite element meshes to obtain the divided three-dimensional ring welding model of the pipeline. The simulation calculation module is used to perform heat transfer simulation calculations on the divided three-dimensional model of the pipe circumferential welding to obtain simulation calculation results. Based on the simulation calculation results, a simulated weld region is constructed, the actual weld region output by the pipe circumferential welding experiment is obtained, the structural differences between the simulated weld region and the actual weld region are compared to obtain comparison results, and the initial information of the molten droplet heat source and the molten motion information are updated based on the comparison results to obtain the updated parameters of the simulated weld region. The circumferential welding analysis module is used to update the simulated weld region using the updated parameters of the simulated weld region to obtain the updated simulated weld region. It then performs temperature field calculations, stress value calculations, and summarizes the evolution law of the forming morphology of the updated simulated weld region to obtain the internal temperature field distribution, residual stress value, and melt spreading morphology of the metal material. Based on the temperature field distribution and the residual stress value, it performs quality analysis of the circumferential welding of the molten droplet heat source, and based on the melt spreading morphology, it performs forming morphology analysis of the circumferential welding of the molten droplet heat source.

9. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor for executing the computer program to implement the circumferential welding analysis method for molten droplet heat sources as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, Used to store computer programs; wherein, when the computer programs are executed by a processor, they implement the circumferential welding analysis method for molten droplet heat sources as described in any one of claims 1 to 7.

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