Research Of The Seawater Hydraulic Swash-plate Axial Piston Pump Based On Seawater Lubrication

Seawater is a kind of clean, non-combustible, widely available, and easy to store and transport material, and is an ideal pressure medium in modern water hydraulics technology, Seawater has lower viscosity and higher vapor pressure than the hydraulic oil, and has brought serious leakage, corrosion and wear problem to the seawater lubricatied axial piston pump, and lays great restraints on its reliability. In order to improve the domestic prototypes'performance and reliability to meet the requirement of practical using, our group propose to carry out research on the reliability of seawater axial piston pump.The reliability problems of the seawater lubricated axial piston pump focus on the challenges of the special physical and chemical properties of seawater. Generally speaking, they are the corrosion resistance reliability, the friction and lubrication reliability, as well as the leakage and sealing reliability.Theory of compressible flow has been investigated in this research. New models to calculate high-pressure angle and to calculate the number of high-pressure pistons have been developed. The influence of the pre-compression angle to the high-pressure ange and to the number of high-pressure pistons has also been discussed, according to the simulation results by Matlab.Theoretical flow rate characteristic with the influence of pre-compression angle has been studied. Then, a new formulation of theoretical flow rate has been generated. Since some of the inputs and structure parameters are stochastic, the reliability of theoretical flow rate has been calculated by utilizing the reliability model of kinematics. The result shows that the reliability of theoretical flow rate is 0.99723 under the design tolerance.A new seawater hydraulic swash-plate axial piston pump with some innovative designs on structure and manufacturaing process has been developed. As for structure, a new cylinder supported bearing structure has been proposed, and a new kind of fixed valve plate which is fixed on the end cap of pump has been developed. As for the manufacturing process, the QPQ technology has been introduced to improve friction pairs. A new kind of mosaic injection molding process has been developed to manufacture the slipper and the valve plate.