A Large-Flowrate On–Off Valve with Hollow Structure for High-Frequency Hydraulic Vibration and Impact System

Abstract

In high-frequency hydraulic vibration and impact systems, the high-speed reciprocating motion of the impact piston, as controlled by the main valve, transfers energy to the target. Therefore, the main valve must have a fast response speed and strong flow capacity. A novel two-stage large-flowrate on–off valve is developed in this study. The first stage is a small-flowrate servo valve, and the second stage is a large-flowrate hydraulic control valve with a hollow spool. The hollow structure not only reduces the quality of the spool and improves the valve dynamic characteristics but also improves the flow capacity and reduces the pressure drop at the valve port. A structural strength simulation is performed, and the deformation and stress of the spool are calculated. Then, the internal flow channel is extracted and the pressure drop characteristics of valve are obtained by simulation. To obtain the dynamic characteristics of the valve, the control equations of the valve are established, and the simulation model is built in Simcenter Amesim software. Then, the structural parameters of the valve body are optimized in this model. Finally, a prototype is developed for hydraulic vibration and impact systems. The experimental results show that the prototype works well, the opening time of the second-stage valve is within 6 ms, and the port pressure drop at a flow rate of 1000 L/min is only 30% of the conventional opening and closing valve of the same diameter.