Research About The Key Technologies Of Fiber Reinforced Plastic Hydraulic Pressure

As an important process of fiber-reinforced composites, sheet molding compound (SMC) technology draws a worldwide attention recently. Because it's high degree of mechanization, high production efficiency, steady product quality, low cost, it quickly becomes an important molding process in the fiber-reinforced plastic (Referred to as FRP) industry. Currently, the domestic research Institute and University which undertake the fiber-reinforced plastic press research are very few, and special hydraulic glass steel press that the domestic enterprises design is minimal.Therefore, on the basis of hydraulic press research of domestic and foreign fiber-reinforced plastic products, the paper has done a more preliminary study for fiber-reinforced plastic hydraulic machineFirst of all, accessing to a large number of papers in the literature, based on the theoretical analysis of theory and fiber-reinforced plastic molding process, special requirements for fiber-reinforced plastic molding process, a set of dynamic leveling micro mold servo system is design, which is Corner leveling system. The paper introduces the basic structure and working principle of the quadrangular leveling system, refers to the FRP hydraulic research results in the home and abroad and related technologies, completes the leveling system of structural layout and hydraulic design calculations starting from the FRP molding process requirements. Comparative analysis of the pros and cons of various control programs, the high-frequency response proportional directional control valve is selected as the core components, and the double acting single rod hydraulic cylinder for the actor components, using electro-hydraulic proportional technology has done the proportion locations simultaneous Control for the four leveling cylinders with the combination of electrical and hydraulic advantages, so the system has the ability of control performance, and ease of computer control.Secondly, the paper analyzes working principle of the core section for the proportion position synchronization control of leveling system. According to flow continuity equation and force balance equation, the mathematical model of the transferring function of all aspects is established, the transfer function block diagram of the valve controlling cylinder system is derived, and the primary slave two-cylinder system transfer function block diagram is derived when the proportional valve control signal is input by the load disturbing, the piston-cylinder displacement as output, the main parameters of the model are analyzed and the values are determined.Again, the paper has done simulation for the leveling system using MATLAB and its control tool .Through researching characteristic curve of the system, the paper analyzes the factors which impacts the control performance and accuracy, completes the calibration valve cylinder system combining with PID control theory for obtaining the corrected characteristic curve of the new system, the response speed and stability are improved, the system performance is made better. Taking into account the four corners precision requirements for leveling system, the synchronization error of the primary slave two-cylinder are simulated by establishing the simulation model of the system after calibration using SIMULIINK. The simulation results shows that synchronization error has little effect and high synchronization accuracy to meet the leveling accuracy.As seen the application of electro-hydraulic proportional control system for synchronous position has important theoretical and practical engineering significance to improve the control performance and precision leveling for the Quadrangular leveling of FRP hydraulic system.