一种液压缸变间隙密封结构及流场分析

A Kind of Variable Clearance Sealing Structure in Hydraulic Cylinders and Its Flow Field Analysis

传统的液压缸间隙密封,因其密封间隙恒定而存在压力升高泄漏随之增大的矛盾。为此,提出一种压力自适应型液压缸变间隙密封结构,在压力作用下活塞中部产生径向弹性变形从而改变密封间隙。基于弹性力学薄壳理论得到活塞径向变形公式,利用ANSYS有限元软件分析了变形区域宽度、厚度等因素对内泄漏和摩擦力特性的影响。结果表明,该密封结构的密封间隙能随压力改变而自适应地变化,从而有效地调节内泄漏,提升密封性能,为设计和制造提供了理论依据。

The shortcoming of gap seal in hydraulic cylinders is that the pressure rises and the leakage increases due to the constant seal gap.Therefore,a kind of variable clearance sealing structure in hydraulic cylinders is proposed with pressure adaptability,in which the radial elastic deformation occurs in the middle of the piston in response to the action of pressure thereby changing the sealing gap.Based on the thin shell theory of elastic mechanics,the radial deformation formula of the piston is obtained.The influence of deformation region width,thickness and other factors on internal leakage and friction characteristics are analyzed by the ANSYS finite element software.The research results show that the sealing gap of the sealing structure can change adaptively with the pressure change,effectively reduce internal leakage and improve sealing performance,which provides a theoretical basis for the design and manufacture.