Analysis On The Mechanical Properties Of Piston Type Pressure Compensator In Deep Sea

The high pressure in the deep-sea environment is the common concern for various underwater equipments and needs to be solved with top priority. Using pressure compensation is a common way for both home and abroad. And piston with pressure compensator works more outstandingly in deep sea environment for long term among all the pressure compensation devices. However, the mechanical properties of the piston are very complex at work, so some research has been made in this paper.Firstly, with the stick-slip phenomenon of piston as the main line, this paper introduces the basic theory, basic characteristics and mechanics model of friction. Then based on presentation of the physical model of stick-slip phenomenon, how the piston pressure compensator works and what will affect its operating performance are discussed.Secondly, to understand the oil compressibility, by analyzing the factors that influence the oil volume, find out the quantitative relationship between them, and precisely calculate the compensation volume at the system work. Then, according to the balance of force and Newton’s second law, the system of static and dynamic mechanics model is set up, through the selection of parameters, the simulation analysis on the calculation example are carried out.Finally, the FEM is applied to the contact mechanics analysis when piston, O-ring and cylinder work. The main factors that can affect the sealing performance of the piston and the frictional force are studied by static analysis. And the pressure difference of the piston group when it starts and stops under various parameters are worked out through dynamic analysis. Conclusion is drawn that the initial compression rate and the coefficient of friction are the main factors that can affect the mechanical properties of piston. To meet the O-ring sealing reliability and the pressure difference is relatively small, use the initial compression rate and coefficient of friction are appropriate small for the sealing material of piston with pressure compensator.