安装状态的O形橡胶密封圈非线性有限元分析

Nonlinear Finite Element Analysis of O-ring Sealing Considering Installation Condition

在煤矿工程实践中,设备的工作寿命和密封性能与O形橡胶密封圈的装配工艺密切相关,因而有必要对O形圈的安装状态进行分析。以某型液压缸内O形圈为例,首先,基于橡胶材料的单轴拉伸实验得到其应力-应变曲线,通过对比发现Mooney-Rivlin模型能够很好的表征橡胶材料特性,并获得其材料参数;然后,利用ANSYS建立了O形圈安装状态的有限元模型并展开分析,获得了安装过程中的应力变化;最后,研究了不同摩擦系数、初始压缩率和安装圆角对O形圈所受应力的影响规律,指出其最佳安装状态。为O形圈的结构优化设计和失效分析提供了理论依据。

In the practice of coal mine engineering,the working life and sealing performance of equipment are closely related to assembly process of O-ring,so it is necessary to analyze the installation state of O-ring.Taking O-ring in a certain type of hydraulic cylinder as an example,and the stress-strain curve is firstly obtained based on the uniaxial tensile experiment of rubber.By comparing with the fitted curve of Mooney-Rivlin model,it is found that the Mooney-Rivlin model can well characterize the properties of rubber and obtain its material parameters.Then,the finite element model of the installation state of O-ring is established by ANSYS,and the mechanical analysis is carried out to obtain stress distribution.Finally,the effects of different friction coefficients,compression and installation fillets on the stress of O-ring are studied,and the optimal installation state is pointed out.The results can provide a theoretical basis for the structural optimization design and failure analysis of O-rings.