A Method Of Local Structure Analysis Of Injection Mold Based On Sub-model Technology

In order to ensure the designed mold structure meet the requirements of stiffness and strength,the structural CAE analysis of mold is used to optimize mold structure based on the simulated deformation results.The injection mold structure is complex,and it takes a lot of time to analyze the finite element structure.It is generally necessary to save computing time by simplifying the entire model and using sparse grids to divide,but the results of such calculations will produce large errors.In order to simultaneously consider the quality and efficiency of the analysis and calculation of the mold structure,this paper presents a method for analyzing local structure of the injection mold based on the sub-model technology.This method firstly obtains a rough solution through global structural analysis.Then the global analysis result is used to generate a sub-model for local analysis.Finally,the sub-model is added to the solution conditions.We can obtain a local and accurate analysis result.The global structural analysis includes the modeling of global CAD model and the addition of constraints and loads in the analysis model.In this paper,a simplified model is established under the assembly framework and a CAD model of the global injection molding model is established using sparse meshing.Then,the constraint and load are automatically added according to the classification of the constraints and loads at different positions in the mold.The creation of sub-models includes the cutting of the global model and the simplification suppression of the sub-model.The regional clustering algorithm is used to find out the nodes in the large deformation area,and the minimum envelope box of these nodes can be used to determine the cutting boundary so as to realize the cutting of the global model sub-model.According to the traversal of the operation features and the recognition of the operation attributes,the original simplified features can be restored.The sub-model's solution conditions include the displacement constraints of the cutting boundary and the original constraints and loads inside the sub-model.This paper uses the displacement interpolation of boundary nodes to realize the addition of boundary displacement constraints.At the same time,the constraint and payload of the sub-model are updated automatically by classifying the original constraints and loads in the model.In this paper,a local analysis system for injection molds is built in UG NX.The feasibility and superiority of the local analysis method for structural analysis are verified by an example.