The Research Of Hydraulic And Control Technology Of Die Casting Under Constant Flow Rate Dumping Pouring

Dumping-type automatic casting is simple and easy to implement. However, the flow of the melt in the casting process changes nonlinearly. Therefore, a constant flow dumping quantitative automatic pouring system is developed to achieve die casting under constant flow rate. The research of hydraulic and control technology of this system has been done in this paper. Details are as follows:The working principle of the low-speed dumping pouring system is described and the articulated position of the hydraulic cylinder is analyzed and the3-D structure of the pouring system is designed. According to the requirements, the characteristics of the hydraulic subsystem and control subsystem are also analyzed.The mathematical modeling of the casting process is built. The mathematical model of the driving force and the melt flow is built. On this basis, the analysis and calculation is done by using MATLAB, and the change law of the driving force and melt flow is gotten. On the basis of analyzing the change law of the melt flow, the hydraulic cylinder output displacement and velocity control curve in the case of constant melt flow casting is gotten.The research of hydraulic and control technology of die casting under constant melt flow is done. Considering the demand of various working status of dumping casting slowly and returning fast, a hydraulic system of large gradient flow rate were designed. In the working condition of low flow, in order to achieve accurate casting, the two hydraulic cylinders are required moving synchronously and tracking a special displacement curve. Considering these demands, the united model building and simulation of hydraulic system and control system has been done by using the software of AMESim and MATLAB on the basic of building the fuzzy and adaptive fuzzy-PID control system by using the MATLAB/Simulink software. The simulation indicated that the fuzzy control was taken in the case of large deviations and the self-adaptive fuzzy-PID control in the case of small, and that a high precise position tracking and synchronous control wad achieved. This method is an effective control method.The experimentally research of the die cadting system under constant melt flow is done. The driving force of the hydraulic system, the pressure of the hydraulic circuit in the casting process and the pouring flow rate are measured and processed. The correctness of the mathematical model and the rationality of the control algorithm are verified.