Injection Molding And Warpage Optimization Of Automobile Radiator Tank Upper Cover

In this paper,the numerical simulation of injection molding and optimization of warpage for the upper cover of the radiator of a car.The study purpose is to numerical simulate the injection molded parts,and to optimize the warpage deformation of injection molded parts so that they can meet the requirements of high precision before the mass production is put into production.This is of great significance for reducing times of test mode,improving production efficiency,reducing production cost and improving injection molding quality.In order to reduce the warpage of the injection products,firstly,the theory of warpage deformation of injection molding products is studied,which includes the theoretical basis of the melt filling process,the basic equations of the viscous fluid mechanics,the mathematical model of the melt flow behavior in the injection molding,and the mathematical model of the warpage of the injection molding.Secondly,taking the upper cover of the radiator water tank for example,the Moldflow software is used to simulate the injection molding process,and the warpage of the upper cover of the radiator tank is 2.374 mm.Through three processes of flow analysis,cooling analysis and warpage analysis,the causes of warpage are abnormal orientation of glass fiber,uneven cooling and uneven shrinkage,and then the warping deformation is reduced by optimizing the mold structure and the pressure preserving curve of the injection molded parts.The specific optimization data are as follows:after the optimization of the cooling system and the pouring system,the warpage is reduced to 1.513 mm,and the warpage is reduced by 36.27%compared with the initial scheme;the warpage deformation is reduced to 1.094 mm after the optimization of the pressure protection curve,and the warpage deformation is reduced by 54.04%compared with the initial scheme.Finally,Optimization of injection molding process parameters by establishing DOE test.the orthogonal test was established with the help of the statistical analysis software Minitab,through the analysis of the extreme data of the Moldflow simulation test,the optimum combination of the process parameters for the warpage of the injection molded parts was obtained for the mold temperature of 90,the melt temperature was 260℃,the injection time was 3s,the pressure holding pressure was 100.000 MPa and the pressure holding time was 40s,through the analysis of the variance and contribution rate of divisor,which gained the significant factor of influencing the warpage deformation is the injection time and the dwell pressure,then by establishing the two order response surface equation for the significant factors,the precise combination of the process parameters is obtained:the injection time is 4.414 s,the pressure holding pressure is 106.270 MP a,the warpage deformation of the product is reduced to 0.872 mm,and the initial scheme is reduced by 63.3%,which completes the high precision warpage optimization target.The research of this paper shows that based on the numerical simulation of Moldflow,combined with the orthogonal test and the two order response surface equation,and warpage theory,material properties,die structure and process parameters are studied and optimized for injection molding,which can effectively reduce the warpage of injection molded parts.