Study On The Influence Of The Variable Cross-section Rotary Dynamic Seal Structure On Contact Pressure Of Sealing Surface

The seal can prevent the oil leaking out from fitting surface, and also can avoid impurity into the device causing the sealing environment polluted. Excellent sealing performance can assist the mechanical device effectively work. Once the seal failure, which will increase the leakage rate of the contact surfaces and increase the wear between the sealing surface and also change the temperature in the environment, these consequences will not helpful for the sealing performance to play normally, weaken the sealing effect, and reduce system efficiency,so the pollution caused by oil leakage of the equipment, non renewable resources problems should be taken seriously in the process of design. Even though the seal’s volume is very small, it plays a important role in fluid machinery, power machinery and so on.With the development of science and technology, the requirements of the using conditions are becoming more and more strict, the using conditions of the seal toward high speed, high pressure, high temperature. The traditional sealing rings generally rely on the strong compression to achieve the sealing function, despite reaching the sealing effect, it also increases the friction between the contact surfaces, high oil leakage and rises the temperature.Traditional seal rings’ processing cost is less, but their sealing performance is poor and also causes serious leakage. When the speed ? of the contact surface and pressure difference increase whose product reaches the limited value 7MPa/s, traditional sealing rings’ shortcomings are more and more prominent, which can not meet the actual condition of the demand. Usually this kind of sealing ring is only suitable for use in sealing pressure P?MPa3.0 and low speed condition.As a representative of the non contact type sealing ring, variable cross-section rotary dynamic seal belongs to a kind of rotary shaft seal, the inner surface near the direction of lubricating grease contacted with a shaft, is consisted of 4 sin waveforms, this kind of seal structure employs fluid dynamic pressure effect, namely as the axis of rotation, it can form hydrodynamic film between sealing surface, the film can effectively avoid the direct contact between surfaces in relative motion, which reduces the wear and the heat generated by friction and extends the life of shaft and seal. With the advantages, this kind of seal ring is widely used in grinding, high pressure, high speed and other harsh environment in the section of rotary fluid sealing.The paper’s research object is the variable cross-section rotary dynamic seal, it will adopt SolidWorks modeling sealing ring, sealing, shaft and assembly and use ANSYS to carryout the finite element analysis, setting the material parameters, the basic displacement and force constraints etc. Study the friction factor, different compression rate, sealing pressure,rubber material parameters, wave number that influence the contact on the wave edge.Analysis changes of wave edge peak contact pressure when the "lip" seal edge structure that has no waveform seal namely the ordinary O shaped sealing ring and the "lip" structure is serrated. Through the research of sealing structure parameters, influence of wave edge structure on the maximum contact pressure on the side of the waveform, the purpose is to provide a theoretical basis for further research and development of the variable cross-section rotary dynamic seal, eventually can develop a high performance sealing products which can Through the research of sealing structure parameters, influence of wave edge structure on the maximum contact pressure at the side of the waveform, the purpose is to provide a theoretical basis for variable cross section rotating fluid dynamic research and development of seal ring,eventually developed a high performance sealing products which can industrialized process and product to reduce the dependence on imported sealing products.