Reasearch On Design And Structure Optimization Of Automobile Sound Insulation Pad Compression Molding

The most common molding process for automotive interior parts is compression molding,which can quickly and efficiently produce the various products required for automotive interior parts.In the process of compression molding,besides molding time,molding temperature,and molding pressure,the uniformity of temperature distribution on the mold forming surface and the stress strain on the mold forming surface also have a great influence on the quality of the product.The shape of automotive interior parts is mostly irregular during the compression molding process.Using the previous experience to design the heating system will lead to uneven temperature distribution on the mold forming surface,unsatisfactory heating effect and long heating time,which have a great impact on the quality and productivity of products.This thesis takes an automotive interior parts enterprise in Wuhu as the research object,designs the mold structure of automobile sound insulation pad and optimizes its heating system.According to the problems of uneven temperature distribution and longer heating time on the mold forming surface,this thesis uses UG software to design the automobile sound insulation pad and its mold structure,uses heat transfer theory to build mathematical model of the heating system of the mold,and then studies the heating characteristics of the mold through orthogonal design experiment and ANSYS finite element simulation.Finally,the heating system of the mold was optimized and verified according to the Taguchi algorithm.The main research contents of this thesis are as follows:(1)Discuss the application environment and functional characteristics of automobile sound insulation pad,and determine its materials and structure.(2)Analyze the material and structure of automobile sound insulation pad,design the mold required for the compression molding of automobile sound insulation pad,and analyze and calculate the heating system of the mold.(3)The heat transfer analysis of the automobile sound insulation pad forming mold is carried out to determine that the heat transfer form in the core and cavity is mainly heat conduction,and the heat transfer form between the mold and the heat transfer oil and the surrounding air is mainly convective heat transfer.And a mathematical model of heat transfer in the heating process is established.(4)The orthogonal test was designed to determine the influencing factors and heating performance evaluation indexes of the mold heating process.The heating process was simulated by ANSYS finite element analysis software,and the results of the orthogonal test were analyzed by the range and variance analysis method.(5)Based on the analysis results of orthogonal experiment,Taguchi algorithm was used to optimize the structure of the mold,and the optimal structural parameters of the mold heating system were obtained and verified by simulation.The main innovations of this thesis are as follows:(1)The heat flow-coupling method is used to simulate the heating system of the automobile sound insulation forming mold,which overcomes the shortcomings of traditional equivalent calculation method to simulate and analyze the heat flow of the molding.The temperature variation along the heating pipe and the temperature distribution on the mold forming surface can be obtained more accurately.(2)The thermo-mechanical coupling method is used to synthesize the automobile sound insulation pad forming mold by the pressure of the molding machine and the thermal stress generated by heating,and to calculate the stress and strain of the mold surface more accurately.(3)By optimizing the heating system of the forming mold,the problem of uneven temperature distribution on the mold forming surface and the long time of temperature rise are changed,the quality and productivity of the automobile sound insulation pad are improved.