Development Of A New-type Pilot Operated Water Hydraulic Relief Valve With Membrane Sealing

Because of low viscosity and bad lubrication of water, sealing and lubricating in the clearance between main valve and sleeve is a key technical problem in design of pilot operated water hydraulic relief valve. In order to solve this problem, a new pilot operated water hydraulic relief valve with membrane sealing is developed in this dissertation.The mechanical model of membrane was established according to the elasticity mechanics, and its numerical calculation was conducted by computer. The discussion about the structural parameters' influences on stress distribution and flexibility was carried out, and the membrane was designed based on the actual application requirement. The static performance of the valve was discussed, and the dynamic mathematical model of valve was also established. The influence of relating structural parameters on valve's dynamic performance were analyzed based on the results of simulation and the structural parameters were optimized.A prototype of this kind of valve with membrane sealing was developed, and the experimental investigation was carried out, including the test of static performance and dynamic performance. Based on the analysis of the experiment results, the performance parameters of the sample were worked out. The experiment states that the valve developed in this dissertation has a wide range in pressure adjusting, good static performance, small overshoot and short risetime. It is also proved that this kind of valve has a strong ability of sealing and lubrication. Because of the distortion of the membrane, the actual risetime is longer than that in the simulation.