Study On Stability Of The Screw-in Cartridge Counterbalance Valve In Balance Circuit

Hydraulic counterbalance valve belongs to the hydraulic valve in the pressure control valve is the core component of the balance circuit, can with the change of the load corresponding to the back pressure, in the hydraulic system to throttle speed, Counterbalance valve performance determines the control performance of the balance circuit, its quality directly affect the system stability. Vehicle rain test hydraulic tilt table system is typical of the balance circuit, traditional tilt table with a hydraulic lock to control the system, due to the hydraulic control one-way valve itself characteristics, falling down an inclined load vibration, tilt the car there is danger of sliding table. The American Sun company of CC** type thread cartridge without guide pressure balance valve instead of hydraulic control one-way valve, through the combination of theoretical analysis and simulation analysis of research methods, analysis of threaded cartridge without guide pressure balancing valve on the valve and the system stability of main parameters, and provide a theoretical basis for the design and optimization of the balance valve.The main contents of this paper are as follows:1) describes the background and significance of the research, introduces the automobile rain test tilt and several kinds of basic balance circuit; an overview of the screw-in cartridge counterbalance valve without pilot operated development present situation and the existing problems. Summarizes the main research contents and methods of the subject.2) describes the tilt table working process, has carried on the theoretical calculation, analyzes the main problems existing in the tilt table, put forward the improvement measures. The technical characteristics of the screw-in cartridge valves, expounds threaded cartridge without the structure the structure and working principle of pressure balance valve guide, and analyzes its performance characteristics.3) the screw-in cartridge counterbalance valve without pilot operated on the numerical analytic mouth area, establish the static and dynamic mathematical model of the valve, and lay a solid foundation for the numerical simulation.4) established the screw-in cartridge counterbalance valve without pilot operated of automobile rain test hydraulic tilt and AMESim simulation model, obtained the system and valve under the condition of dynamic response curve, analysis of the load, the damping valve core, the annular gap, pressure spring stiffness and preload, the valve cone angle on the valve and the system stability influence. The results show that the annular gap height influence on the stability of the valve and the maximum system.5) using CFD simulation software of the screw-in cartridge counterbalance valve without pilot operated flow characteristics in the simulation analysis, obtains the valve port in different open degree of pressure distribution and velocity distribution nephogram and find out the location and variation of the negative pressure region. Analysis of the impact of negative pressure zone formed by cavitation and cavitation on the stability of the couterbalance valve and the hydraulic system, put forward to reduce or prevent the negative pressure zone.