| Forging hydraulic press is one symbol which weighs a country machinery manufacturing level and ability. Forging oil press is considered as substitute of large type forging hammer and middle-small traditonal forging water press because of its fast forging speed, high control accuracy and high automatization etc. Developing the hydraulic control system essential characteristics research on the forging oil press has important theoretical significance and practical application value. It can provide the technical support for hydraulic system design optimization of the modernized forging oil press; it can improve hydraulic control system essential characteristics, structure parameters and system design of the existing forging oil press, optimize control technology, and then enhance forging oil press overall level.Aming at modernization forging oil press rapid, non-impact and high precision, the influencing factors of forging oil press operating characteristics and the forging oil press control characteristics had been studied. This work around these two special subjects had been carried on as follows:Using the mechanism modeling technology, based on hydraulic system dynamic modeling research of the forging oil press, the essential components mathematical model consist of the kind of cartridge directional valves, the kind of cartridge pressure valves, the triple-stage cartridge valves, the electro-hydraulic proportional cartridge valves, the accumulator, the pipeline, the executive mechanism, the hydraulic press vibration etc. were found. According to these, different hydraulic control system mathematical model of fast forging circuit were found. All above models are laying a theoretical foundation for the essential characteristics research of the forging oil press.Based on the theoretical modeling foundation, through the massive simulations and the experimental study, comprehensive and systematic analysis of forging oil press rapid influencing factors, which include working speed, the essential components static and dynamic performance, the set-pressure time, the unloading pressure time, various valves coordination control and electro-hydraulic proportional control system design and so on, were carried out. From pressure relief and unloading impact, the pipeline pressure impact and sudden unloading impact vibration three aspects, the influencing key factors of forging oil press impact vibration were conducted. In combination with measured data of production progress, using simulation technology, the ideal release of pressure curve, the influence rules of pipeline to the system impact vibration in the different position, the measures of reducing unloading to lead to the press and the foundation vibration had been obtained, it has the practical significance and the application value.The valve controlled cylinder characteristics of the forging oil press was studied. Through designing the controller parameters, the forging hydraulic press hydraulic control system control characteristics was optimized, the return cylinder pressure jump was reduced, the hydraulic system rapidity was enhanced. What is more important it was applied and verified in the actual forging oil press.On the basis of the simulation and experimental study, the control characteristics of the switching type fast forging circuit, the differential overflow fast forging circuit and the proportional control fast forging circuit had been analyzed and compared. The corresponding computer fast forging procedures were given. The simulation and the experimental with emphasis on forging circuit using accumulator were studied, the basis of selecting calculation of accumulator was proposed, the simulation and test results had proved energy conservation of fast forging by using the accumulator is feasible and realized, and the mathematical model of the accumulator and the fast forging circuit using accumulator is accuracy.
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