Analysis of switching time for pilot operated directional control valve

Janusz Rajda,

Edward Lisowski

Abstrakt

The paper presents an analysis of switching time for pilot operated directional control valve [1–3] in a typical hydraulic system, in which the actuator is a hydraulic cylinder. A mathematical model has been built which contains equations of motion for the valve and actuator components, the balance of fluid flow, flow through the gap, and the principle of conservation of momentum and the flow curves of pressure relief valves [6, 8]. The system of equations is solved by fourthorder Runge-Kutta method. A survey to find minimal switching time has been conducted [4]. Positive overlap value, the coefficient of its movement resistance and control pressure value have significant impact on the switching time in the tested valve.

Słowa kluczowe: modeling of hydraulic systems, spool type directional control valve
References

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