Research On Pneumatic-hydraulic Composite Transmission System Of The Electrical Upsetting Machine

Valves are of the key parts of engines. With the increasing of production and performance requirements of automobiles in recent years, the requirements for engine valve manufacturing are increased accordingly. Electrical upsetting is widely used in our country. Due to the variety of parameters during electrical upsetting process, both domestic and international scholars have done much research work in how to improve the electrical upsetting process by optimizing the parameters. Regarding to the electrical upsetting machine itself, there is very little research on the transmission system. With the progressing and application extension of pneumatic and hydraulic technology, performance requirements for electrical upsetting machines have been put forward. How to improve the control precision of the electrical upsetting machine, strengthen environmental adaptive ability, improve dynamic performances, shorten design cycle, and optimize systematic scheme are the problems need to be solved urgently. Studying dynamic characteristics of pneumatic and hydraulic transmission system of electrical upsetting machine is important for improving electrical upsetting machine performances.Based on summarizing transmission systems of domestic and international electrical upsetting machines and according to the principles of practicability, reliability, economization and the enterprise requirements, a pneumatic-hydraulic composite transmission system designed and manufactured. In order to analyze and compare the pneumatic-hydraulic composite transmission system and the entire hydraulic transmission system, the mathematic models of two different transmission systems were set up. Utilizing the upward structure of Matlab/Simulink toolbox, the author produced whole model of the system. The module parameters values were given according to the actual working conditions. The step responses were simulated and tested. The numerical simulation and the results of experiments shown:1. The testing results show that the system is reasonable in the whole design, advanced in technologies, reliable at performances and economical at cost. The system is approved to have achieved the expected results. 2. The pressure curves from the numerical simulation and experiments were approximately coincided each other, proving that the simulation model is accurate and effective.3. The comparison of pneumatic-hydraulic composite transmission system with the entire hydraulic transmission system shown that the former system's dynamic characteristics were better.The modeling and simulation method of the transmission system of the electrical upsetting machine which the author put forward have guiding significance in studying influences of dynamic characteristics to electrical upsetting and putting forward the corresponding improvement measures.