Structure Design And Experimental Study On A Hydraulic Pump Applied In Deep Sea

Using seawater as the medium of fluid power transmission is the hot-spot in the field of the deep-sea underwater work machinery. The seawater hydraulic technology not only simplify the structure, maintenance and operation of machinery, but also is compatible with ocean environment. In this thesis, a motor-pump prototype which has integral structure of combining the the seawater hydraulic axial piston pump and the DC motor filled with oil is researched . The DC motor and seawater hydraulic pump share the same shaft and bearings. This motor-pump has many advantages such as miniaturization, portability and good lubricating condition of the bearing etc, so that can be used for the uderwater work machinery in deep-sea.Basing on the working conditons of Hydraulic Pump applied in Deep Sea and the technological difficulities, the solutions of the key technology of the prototype are presented. Moreover, the prototype has been made and researches about its performances test are carried out.By comparing availabe three structures of slipper, a new type of slipper with back taper structure is developed. In order to analyse the mechanical characteristic of the slipper, a mechanical model is built according to the plastic mechanics theory. The results demonstrate that the new slipper not only has simple structure, lower friction coefficient and anti-wear, but also there are enough bonding force to keep the internal and external parts of the new kind of slipper being assembled reliably. The results of test manifests that the structure and make processing of the new kind of slipper are reasonable and it has outstanding performances.Two mechanics models are established according to two combination of cylinder bore and piston pair and calculated by computer. The results show the change trend of opposite force of swashplate, lateral pressure of piston, contact stress and pv- value. By comparison, the structure with the constant length of fit shows much better performances than the other one . It can improve mechanics performances and reduce wear effectively.Using the software AMESim, a inlet or outlet valve's model of under seawater hydraulic pump is analysed and its working process is also simulated. According to the result of simulation, the influences of clearance volume, weight of valve, stiffness of spring and working pressure on working performance of Hydraulic Pump applied in Deep Sea are discussed and the methods of decreasing the adverse effects are presented.A prototype is successfully made. performance tests about it are carried out. The results show that the working pressure of prototype can reach 13.5MPa and out-flow rate can be 8.3L/min.