Design & Simulation of a Hydraulic Back Pressure Valve with a Large Flow Range

A hydraulic back pressure valve with a large flow range up to not less than 100L/min was designed. In order to meet the requirements of low cracking pressure and large applicable flow range, the valve was designed in a pilot operated style with a flat valve port of main valve. Area difference between the front and rear of main spool was adopted to keep the valve port self-sealing and adjustable damping plugs were used to easily regulate the dynamic performance of the valve. The mathematic models of the valve were established and simulations were carried out. Then, the influences of some major structural parameters such as volume before main throttle, volume of main spring chamber, dimensions of slender holes of damping plugs and the main throttle were obtained. The simulation results show that the valve has good flow adaptability, and the pressure shock can be cut down remarkably by reasonably setting the parameters.