Intelligent Design Of Injection Mold Gating System Based On Moldflow And Activex Technology

Feed system is the flow-way which connects the nozzle to the cavity, it consists of main runner, branch runner, gate and cold slug well. It is the important part of the mold design and has great impact on the performance, size, internal quality and external quality of the plastic parts, the structure of mold and the utilization of raw materials.With the development of technology, CAE is playing an increasingly important role in industry. Many well-known CAE softwares provide the secondary development platform for the users, it can make the finite element softwares more useful. Moldflow is a famous plastic flow analyzing software。Based on its secondary development and ActiveX technology, this paper developed the intelligent design system for injection mold's feed system. The system is composed of four separate programs as bellow:(1) An intelligent program of gate type selection, which can provide a group of feasible gate type and a group of recommended gate type by considering the shape and quality demand of plastic parts, the material type and the number of cavity(2) An intelligent program of gate location selection, which gives reasonable gate location by means of spline interpolation considering the gate type, the quality demand of the part,the thickness of wall and the weld lines, warp, balance of filling ,pressure loss,air trap in the Finite element analysis results.(3) An intelligent program of gate size selection, which at first gives a reasonable gate size range by considering the thickness of wall, the amount of shear rate and its stability requirement, then gives the relationship between the gate size and the cooling time of the gate, the relationship between the gate size and the pressure loss of the gate, after the design of gate type and location has been finised.The user can choose the most suitable gate size according to the actual process parameter.(4) An intelligent program of runner selection, which can provide the reasonable diameter of the main runner by considering the amount of shear rate and provide the reasonable diameter of the branch runner by considering both the amount of shear rate and the material type.The system will check the feed system after it has been designed and gives a summary of the result. The user can judge the result , if he is not satisfied the user can reset the parameters to start a new design.The example shows that the system is feasilble.The intelligent design system can improve the efficiency of mold design, raise the success rate of mold trial and shorten the cycle of design and manufacturing ; it reduces the dependence on experience and let the less experienced designers can design a more reasonable feed system.