真空环境下C形密封圈力学性能和泄漏率的有限元分析

The finite element analysis on status performance and leakage rate for the C-ring in vacuum

利用大型非线性有限元软件Marc建立了C形密封圈(简称C形圈)三维有限元模型,用单轴拉伸试验确定了C形圈材料聚四氟乙烯的参数。介绍了C形圈密封机理以及泄漏通道的形成机理。重点分析了介质压力对C形圈主材料聚四氟乙烯的最大Von Mises应力的影响以及C形圈压缩率和介质压力对C形圈主材料聚四氟乙烯接触应力的影响。同时,利用罗思·A密封理论分析了C形圈压缩率以及密封件表面粗糙度对C形圈泄漏率的影响。研究表明:当介质压力增大时,C形圈聚四氟乙烯部分的最大Von Mises应力整体是增大的;随着C形圈压缩率和介质压力的增大,C形圈聚四氟乙烯部分的接触应力也在增大;C形圈的泄漏率随着压缩率的增加而减小,随着密封件表面粗糙度的增大而增大。

Based on uniaxial tensile test it obtains C-ring material PTFE parameter,establishes the 3D model of the C-ring in the dry gas seal in software MARC,introduces the theory of C-ring seal and the constitute of leakage channel.It analyzes the influence of compressibility and medium pressure on the C-ring max Von Mises stress,the max contact pressure,discusses the influence of compressibility and surface roughness of sealing element to the C-ring leakage rate.The results show that the maximum Von Mises stress of the C-rings PTFE is larger,the contact stress of C-rings PTFE and the medium pressure increases with the compressibility at the medium pressure increases,the leakage rate of C-rings decreases with the medium pressure increases and increases with the face roughness of sealing element increases.