Development of a large flow-rate high speed on/off valve for Underwater Hydraulic Ejection System

For ROV carried Underwater Hydraulic Ejection Systems (UHES), the initial ejecting speed and ejecting distance depends on the response of its high speed on/off valves, together with its steady and transient flow rate. However, the flow rate capacity and response of general high speed valve are too small and too slow to meet the demand of most UHES. In this paper, a double spool type on/off valve is put forward to create a flowing-out type valve port, so that the steady flow force could be reduced to 1/3, and the direction of transient flow force could be changed to help the electromagnet opening or closing the valve port. After analyzing the steady and transient flow force of the double spool and flowing-out type valve port, its model is established, and the effects of flow force on this valve are compared with general poppet valves through Computational Fluid Dynamics (CFD) software. Simulation results show that, the valve's response could reach 2.25ms (on) and 2.15ms (off) at 48V power supply while the rated flow rate is 60L/min. Experimental results are also satisfactory.