Development Of CAD/CAE Integrated Design & Optimization System For Hot Runner Mold

Hot runner molds have been widely used in the injection industry in recent years due to good economy,high automation and good adaptability to various molding processes.However,the complicated structure of the hot runner mold brings a heavy workload on designers.Improve the level of automation of design has become one of the urgent problems.Furthermore,the layout of the hotflex in the manifold has a significant influence on the temperature of the plastic melt and the final quality of injection products.Too high or too low temperature of plastic melt will lead to some defects such as dark spots,dark lines and bubbles.Currently,the design of hotflex layout still relies on the empirical parameters or repeated FEM temperature analysis to get some better geometric parameters.Since this tradition way of designing hotflex is low efficient and cannot assure the achievement of optimal design solution,it is necessary to introduce engineering optimization technology to realize the automatic optimization of hotflex layout.In order to improve the automation of design and optimization in hot runner mold designing,some relevant design and optimization technologies was proposed in this paper.A CAD/CAE/CAO integrated Hot Runner Mold Design and Optimization System(HRMDOS)was also developed based on these technologies.To improve design automation,a flexible manifold design method and a rule-based automatic assembly technique were proposed.The flexible manifold design method treated each manifold as a combination of some simple parametric sketch units.The design of a complicated manifold is a process of automatic parameterizing these units and creating constraint relationship between them.This method of manifold designing is flexible and has a good efficiency.The rule-based assembly technique expressed the rules of assembling mold plate parts and standard parts in a form of triples.Based on these rules,each standard parts was automatically constrained when inserted into the hot runner mold assembly and thus greatly improved the efficiency of assembling.An integrated information model of manifold(IIMM)for the information sharing and interaction between CAD/CAE/CAO is proposed in this paper.The model contains the information of manifold geometry modeling,the parameters for FEM analysis and the evaluation information of design solution.The interaction and sharing between different CAD,CAE and CAO platforms and IIMM was realized by developing data exchange modules using their specific APIs.The automatically generation of finite element analysis model and the design evaluation were realized based ANSYS/APDL.Finally,on the platform iSight and ANSYS,an intelligent optimization process was created to automatically optimize the hotflex layout to achieve an optimal temperature distribution in the manifold.The feasibility and practicability of this method were also verified by three cases.This research work can greatly improve the automation of design and optimization in the hot runner mold design process.Hence,the design workload will be reduced and the mold development cycle will be shortened.The proposed technology for integrating different CAD/CAE/CAO platforms has a good theoretical and practical application value.It can not only be used for the automatic optimization of hotflex layout,but also be applied to other engineering optimization problems.