| description abstract | According to the function and operating characteristics of water hydraulic relief valves in a highpressure water pipe system, a novel onestage relief valve with a oneway damper was designed and analyzed in this study. The oneway damper consists of a damping chamber and a check valve. Moreover, a damping orifice is bored along the axis of the checkvalve spool. When the main spool moves to open the valve port, the check valve is fully open, and the damping orifice generates no damping force on the main spool; otherwise, the check valve is completely closed, and the damping orifice produces a damping force on the main spool. Furthermore, based on a mathematical model describing the dynamic characteristics of the relief valve, the effect of the oneway damper on the dynamic characteristics of the relief valve was simulated and analyzed, and certain optimal parameters of the oneway damper were obtained (e.g., the diameter and length of the damping orifice and the initial volume of the damping chamber). Lastly, the experimental results obtained from a prototype of the relief valve, which was manufactured to the optimal dimensions, demonstrated that the pressure overshoot was 7.5%, the response time was 1.43 أ— 10−2 s, and the transition time was 3.9 أ— 10−2 s. Thus, the oneway damper could significantly improve the dynamic characteristics of the relief valve. | |