MOLDFLOW-based DOE simulation analysis method for automobile instrument plastic part molding

Abstract

The invention discloses a DOE simulation analysis method for automobile instrument plastic part molding based on MOLDFLOW. The DOE simulation analysis method comprises the steps that a three-dimensional model of a plastic part is imported into MOLDFLOW software; injection molding process parameters are selected in the MOLDFLOW software; performing grid local densification processing on the three-dimensional model of the plastic part; the factors influencing the deformation of the plastic part are used as DOE analysis variables, and the DOE analysis method is adopted to determine the factor dwell time and pressure which have the largest influence on the forming of the plastic part; and increasing the dwell time and the pressure according to the DOE analysis result so as to optimize the plastic part forming process. And by utilizing the parallel computing function of the MOLDFLOW and adopting a DOE analysis method, the factor which has the greatest influence on the plastic part is calculated, so that the design process of the plastic part is optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding processes, and particularly to a DOE simulation analysis method for the molding of automotive instrument plastic parts based on MOLDFLOW. Background Art

[0002] During the molding process of automotive instrument plastic parts, the plastic melt is affected by processes such as flow, pressure holding, and cooling in the mold cavity, and various physical quantities in the plastic parts also change accordingly.

[0003] In traditional technical solutions, MOLDFLOW software is used to simulate the molding process of automotive instrument plastic parts. MOLDFLOW is a type of CAE analysis software. MOLDFLOW uses computer numerical simulation methods combined with finite element analysis methods to solve the changes in various physical quantities during the flow, pressure holding, and cooling processes of the plastic melt in the mold cavity, thereby obtaining the distribution of the temperature field, pressure field, and velocity field of the plastic melt, and further predicting various potential problems during the filling, pressure holding, and cooling processes. However, MOLDFLOW analysis requires a large amount of computing resources and time to analyze specific variables, resulting in low simulation efficiency. Summary of the Invention

[0004] Based on the above situation, the main purpose of the present invention is to provide a DOE simulation analysis method for the molding of automotive instrument plastic parts based on MOLDFLOW, which utilizes the parallel computing function of MOLDFLOW and adopts the DOE analysis method to calculate the factors that have the greatest impact on the plastic parts, thereby optimizing the plastic part design process.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A DOE simulation analysis method for the molding of automotive instrument plastic parts based on MOLDFLOW, comprising the steps of:

[0007] S100, import the three-dimensional model of the plastic part into MOLDFLOW software;

[0008] S300, select injection molding process parameters in MOLDFLOW software;

[0009] S500, perform local mesh densification on the three-dimensional model of the plastic part;

[0010] S700, use the factors that affect the deformation of the plastic part as DOE analysis variables, and adopt the DOE analysis method to determine the factors that have the greatest impact on the molding of the plastic part, namely the pressure holding time and pressure;

[0011] S900, increase the pressure holding time and pressure according to the DOE analysis results to optimize the molding process of the plastic part.

[0012] Preferably, the three-dimensional model of the plastic part is a simplified three-dimensional model established using CATIA software, including reducing the degrees of freedom of the three-dimensional model, simplifying the geometric shape of the three-dimensional model, and / or simplifying the material model.

[0013] Preferably, the imported three-dimensional model of the plastic part includes injection-molded parts, mold structures, and runner systems.

[0014] Preferably, the injection molding process parameters include melt temperature, mold temperature, and speed / pressure switching when the filling volume reaches 99%.

[0015] Preferably, the step S500 of performing local mesh refinement on the three-dimensional model of the plastic part includes: adjusting the mesh size to 0.5 mm.

[0016] Preferably, the factors affecting the deformation of the plastic part in the step S700 include mold temperature, melt index, V / P switching position, holding pressure, and time.

[0017] Preferably, the S700 includes steps

[0018] S701, after performing DOE analysis on the plastic part, determining the position node with the largest change among the DOE analysis variables, and setting a reference anchor point in the three-dimensional model of the plastic part, and defining the distance between the node and the reference anchor point as the critical dimension;

[0019] S702, adjusting the size of the critical dimension to achieve the purpose of controlling the deformation of the three-dimensional model of the plastic part;

[0020] S703, resetting the parameter variable values affecting the deformation of the plastic part to obtain the holding time and pressure, which are the factors having the greatest impact on the molding of the plastic part.

[0021] The present invention also discloses an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the steps of any method of the present invention are implemented.

[0022] The present invention also discloses a computer-readable storage medium, characterized in that the computer-readable storage medium stores machine-executable instructions. When the machine-executable instructions are called and run by a processor, the processor executes any method of the present invention.

[0023] The present invention also discloses a manufacturing method of an automotive instrument plastic part, characterized in that the method manufactures the automotive instrument plastic part according to any method of the present invention.

[0024] The present invention utilizes the parallel computing function of MOLDFLOW to allocate computing tasks to multiple processors for simultaneous computing, thereby improving computing efficiency. The DOE analysis method is adopted to determine that the factors having the greatest impact on the plastic part forming are the holding time and pressure. The DOE analysis method can set intervention variables of the factors that may affect the plastic part forming, perform permutation and combination operations on the parameters, calculate the factors having the greatest impact on the plastic part, and achieve easily finding the factors affecting the plastic part forming by using DOE optimization. The DOE analysis method can help engineers find the optimal combination of mold design and process parameters more quickly and effectively. Meanwhile, when performing mesh analysis, reducing the number of meshes, optimizing material parameters, etc. can effectively shorten the analysis time.

[0025] Other beneficial effects of the present invention will be elaborated in the specific implementation manners through the introduction of specific technical features and technical solutions. Those skilled in the art should be able to understand the beneficial technical effects brought by the said technical features and technical solutions through the introduction of these technical features and technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The following will describe the preferred embodiments of the MOLDFLOW-based automotive instrument plastic part forming analysis method according to the present invention with reference to the drawings. In the figures:

[0027] Figure 1 It is a flowchart of the DOE simulation analysis method for the MOLDFLOW-based automotive instrument plastic part forming according to a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] Figure 1 It is a flowchart of the DOE simulation analysis method for the MOLDFLOW-based automotive instrument plastic part forming according to a preferred embodiment of the present invention, including the steps:

[0029] S100, importing the three-dimensional model of the plastic part into the MOLDFLOW software;

[0030] S300, selecting injection molding process parameters in the MOLDFLOW software;

[0031] S500, performing local mesh densification on the three-dimensional model of the plastic part;

[0032] S700, taking the factors affecting the deformation of the plastic part as DOE analysis variables, and adopting the DOE analysis method to determine the factors having the greatest impact on the plastic part forming, namely the holding time and pressure;

[0033] S900, increasing the holding time and pressure according to the DOE analysis results to optimize the plastic part forming process.

[0034] The parallel computing function of MOLDFLOW is utilized in the present invention to distribute computing tasks to multiple processors for simultaneous calculation, thereby improving the computing efficiency. The DOE analysis method is adopted to determine that the factors having the greatest impact on the plastic part forming are the holding pressure time and pressure. The DOE analysis method can set intervention variables for the factors that may affect the plastic part forming, perform permutation and combination operations on the parameters, calculate the factors having the greatest impact on the plastic part, and achieve easily finding the factors affecting the plastic part forming by using DOE optimization. The DOE analysis method can help engineers find the best combination of mold design and process parameters more quickly and effectively. Meanwhile, when performing mesh analysis, reducing the number of meshes, optimizing material parameters, etc. can effectively shorten the analysis time.

[0035] In a preferred embodiment, the three-dimensional model of the plastic part is a simplified three-dimensional model established by using CATIA software, which may include reducing the degrees of freedom of the three-dimensional model, simplifying the geometric shape of the three-dimensional model, and / or simplifying the material model. Since the MOLDFLOW software cannot simplify data and can only modify the meshes after drawing the meshes, the areas that need to be optimized in the three-dimensional model of the plastic part can be optimized first in the CATIA software and then directly imported into the MOLDFLOW software to draw meshes.

[0036] In a preferred embodiment, the imported three-dimensional model of the plastic part includes an injection molded part, a mold structure, and a runner system.

[0037] In a preferred embodiment, the injection molding process parameters may include the melt temperature, the mold temperature, and the speed / pressure switch when the filling volume reaches 99%.

[0038] In a preferred embodiment, the step S500 of performing local mesh densification on the three-dimensional model of the plastic part includes: adjusting the mesh size to 0.5 mm. In a specific embodiment, since some plastic part structures are relatively complex and special, such as a lamp barrel, local mesh densification needs to be performed on the simplified three-dimensional model of the plastic part. For example, the original mesh size is 1.5 mm, and the local mesh size after adjustment is 0.5 mm.

[0039] In a preferred embodiment, the factors affecting the deformation of the plastic part in step S700 may include the mold temperature, the melt index, the V / P switch position, the holding pressure, and the time, etc.

[0040] In a preferred embodiment, S700 may include steps

[0041] S701. After performing DOE analysis on the plastic part, determine the position node with the largest change among the DOE analysis variables, set a reference anchor point in the 3D model of the plastic part, and define the distance between the node and the reference anchor point as the critical dimension;

[0042] S702. Adjust the size of the critical dimension to control the deformation of the 3D model of the plastic part;

[0043] S703. Reset the parameter variable values that affect the deformation of the plastic part to obtain the factors that have the greatest impact on the molding of the plastic part, namely the holding pressure time and pressure.

[0044] In the specific implementation, it can be seen from the analysis of the DOE result curve that the biggest factor affecting the deformation of the plastic part is the holding pressure setting, including the holding pressure time and pressure. Therefore, reset the holding pressure curve, increase the holding pressure and time, and perform analysis again. By verifying the optimized design variable combination, it can be concluded that increasing the holding pressure and time significantly improves the deformation of the lamp barrel.

[0045] Through actual verification, it can be found that if the same plastic part is designed using the simulation analysis method of the present invention, the deformation of the plastic part can be greatly improved. For example, when verifying the lamp barrel plastic part, the maximum deformation of the lamp barrel plastic part designed using the conventional technology is 2.610 mm, while the maximum deformation of the lamp barrel plastic part designed using this solution is 2.276 mm. It can be seen that through the DOE optimization analysis of the present invention, the deformation of the plastic part shows an obvious downward trend as the holding pressure and time increase, and the deformation is significantly improved. During subsequent actual injection molding, the increase in the holding pressure and time should be mainly considered.

[0046] The present invention also discloses an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the steps of any method of the present invention are implemented.

[0047] The present invention also discloses a computer-readable storage medium storing machine-executable instructions. When the machine-executable instructions are called and run by a processor, the processor executes any method of the present invention.

[0048] The present invention also discloses a manufacturing method for an automotive instrument plastic part. The method manufactures the automotive instrument plastic part according to any method of the present invention.

[0049] It should be noted that in the present invention, step numbers (letter or number numbers) are used to refer to certain specific method steps, solely for the purpose of convenience and brevity of description, and by no means to limit the order of these method steps by letters or numbers. Those skilled in the art can understand that the order of relevant method steps should be determined by the technology itself and should not be unduly restricted by the existence of step numbers.

[0050] Those skilled in the art can understand that on the premise of no conflict, the above preferred solutions can be freely combined and superimposed.

[0051] It should be understood that the above embodiments are merely exemplary and not restrictive. Without departing from the basic principles of the present invention, various obvious or equivalent modifications or substitutions that those skilled in the art can make to the above details will be included within the scope of the claims of the present invention.

Claims

1. A DOE simulation analysis method for the molding of automotive instrument plastic parts based on MOLDFLOW, characterized in that, Including the steps: S100, Import the 3D model of the plastic part into MOLDFLOW software; S300, Select injection molding process parameters in MOLDFLOW software; S500, Conduct local mesh densification processing on the 3D model of the plastic part; S700, Take the factors affecting the deformation of the plastic part as DOE analysis variables, and use the DOE analysis method to determine the factors with the greatest influence on the molding of the plastic part, namely the holding pressure time and pressure; S900, Increase the holding pressure time and pressure according to the DOE analysis results to optimize the molding process of the plastic part.

2. The DOE simulation analysis method for the plastic part forming of an automotive instrument based on MOLDFLOW according to claim 1, wherein The 3D model of the plastic part is a simplified 3D model established using CATIA software, including reducing the degrees of freedom of the 3D model, simplifying the geometric shape of the 3D model, and / or simplifying the material model.

3. The DOE simulation analysis method for the plastic part forming of an automotive instrument based on MOLDFLOW according to claim 2, wherein The imported 3D model of the plastic part includes an injection molded part, a mold structure, and a runner system.

4. The DOE simulation analysis method for the plastic part forming of an automotive instrument based on MOLDFLOW according to claim 1, wherein The injection molding process parameters include the melt temperature, the mold temperature, and the speed / pressure switch when the filling volume reaches 99%.

5. The DOE simulation analysis method for the plastic part forming of an automotive instrument based on MOLDFLOW according to claim 1, characterized in that The step S500 of conducting local mesh densification processing on the 3D model of the plastic part includes: adjusting the mesh size to 0.5 mm.

6. The DOE simulation analysis method for the plastic part forming of an automotive instrument based on MOLDFLOW according to claim 1, characterized in that The factors affecting the deformation of the plastic part in the step S700 include the mold temperature, the melt index, the V / P switch position, the holding pressure, and the time.

7. The DOE simulation analysis method for the plastic part forming of automotive instrument based on MOLDFLOW according to claim 1, wherein, The S700 includes the steps, S701, After conducting DOE analysis on the plastic part, determine the position node with the largest change among the DOE analysis variables, and set a reference anchor point in the 3D model of the plastic part. Define the distance between the node and the reference anchor point as the key dimension; S702, Adjust the size of the key dimension to achieve the purpose of controlling the deformation of the 3D model of the plastic part; S703, Reset the parameter variable values affecting the deformation of the plastic part to obtain the factors with the greatest influence on the molding of the plastic part, namely the holding pressure time and pressure.

8. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method described in any one of claims 1 to 7 above.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores machine-executable instructions. When the machine-executable instructions are called and run by the processor, the processor executes the method described in any one of claims 1 to 7 above.

10. A manufacturing method for a plastic part of an automotive instrument, characterized in that, The method manufactures plastic parts for automotive instrument panels according to the method described in any one of claims 1 - 7.

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