Design And Research Of Water Hydraulic Relief Valve

Water with abundant quantity, environmental, safety, and many other advantages.With water as a hydraulic system intermediary become a main direction for the futuredevelopment. And the relief valve in the hydraulic system is an integral part of theoriginal. Do overflow valves, safety valves, unloading valves and other uses. Mineraloil and water have different physical and chemical properties. Therefore, hydrauliccomponents of its structure and properties of the requirements will be different. Forlong-term development and social needs, water hydraulic technology has entered anew stage of rapid development.In view of the water hydraulic technology, this topic is put forward to develop acompact structure, light weight, small volume and high efficiency water pressurerelief valve. The maximum working pressure of the valve is14mpa and rated flow of10l/min. The use of direct-acting valve seat structure, initially intended to use water asa medium. And demonstrate the usefulness of the above design and scientific. Specificas follows:Firstly, a comparative analysis of the performance of water medium is differentfrom mineral oil. Due to their different physical and chemical properties, it made avariety of technical problems arising in the application of water hydraulic valves.Such as cavitation, vibration, wear, leaks and seals, as well as flow force problems.Then based on the structural characteristics of the existing direct-acting andpilot-operated relief valve, in order to overcome the technical problems of waterhydraulic analyzes of the secondary throttle and flow force compensation method.Then according to the design requirements of water hydraulic relief valve, keytechnical problems exiting in the water hydraulic relief valve for valve’s structuredesign and determine the size. Taken as the partial pressure of the secondary structureof the throttle, reducing cavitation influence; leaving the spool fixed and seat sport,can compensate for part of the flow force, improve the response performance reliefvalve. By making both ends under pressure to reduce the stiffness of the spring, it canto increase the sensitivity of the valve. In addition, as the hydraulic pressure at bothends of the front and rear seats, and the spring stiffness is reduced, so that when the rear end of the seat connection unloading hole only against a small spring force andthe seat can have a great degree of opening to achieve unloading functions.And it discusses the relief valve performance indicators, including staticperformance and dynamic performance indicators. Then introduces the Matlab andSimulink software tools, based on the software will block diagram of mathematicalmodel in machine language to express. Through the model of the establishment, it canto analysis the static and dynamic characteristic of the relief valve. Including it entryvolume, a two-stage throttling mouth sealing problems and the influence of damping,etc. And the unloading relief valve performance analysis model is established and thesimulation results of pressure and valve opening. Further structural parameters of therelief valve design optimization.Finally discusses the relief valve MTBF test scheme. With accelerated life testand the method of equivalent sample, according to the fault tree analysis, set up testsystem, get the relief valve failure samples, MTBF finally obtained by statisticalanalysis.