快开式压力容器异型密封圈有限元分析

密封圈依靠弹性体材料的弹性在初始装配过盈量或预加载荷的作用下实现自密封.为了解决密封圈在快开式压力容器中的泄露问题并改善丁晴橡胶密封圈的抗疲劳破坏性能,采用有限元的方法对快开门的结构进行简化并对其不同间隙、不同硬度的情况进行分析.首先建立几何简化模型,其中材料模型采用Mooney-Rivlin模型,再分别对硬度为60、70、80、90和间隙为2mm、3mm、4mm的模型进行有限元分析.结果表明：材料的硬度越大,密封圈的变形量越小,硬度为70时的最大等效应力最小,为10.917 MPa;间隙越大,密封圈挤入间隙的体积越大,间隙为2mm时丁晴橡胶的最大等效应力最小,为11.418MPa.综合考虑丁晴橡胶的变形回弹、老化、疲劳破坏等因素,选取合适的硬度为70Hr,合适的间隙为2mm,在此条件下,既能解决密封圈泄漏问题又能改善它的使用寿命.

Finite element analysis of special-shaped sealing ring on quick actuating pressure vessel

To solve the leak problem of seal rings in quick-opening pressure vessels,and improve fatigue rupture resistance of NBR（nitrile rubber buna） seal rings,the finite element method was used to simplify the quick-opening structure and analyze the situations of different clearances and hardnesses.Firstly,the simplified model was built and the Mooney-Rivlin model was used as the material model.Then the models with the hardnesses of 60,70,80,90 and the clearances of 2 mm,3 mm,4 mm were taken by finite element analysis.The result shows that greater hardness of materials may lead to less deformation of seal rings and under the hardness of 70,the minimum value of the maximum equivalent stress is 10.917 MPa.Also,the greater clearance may lead to the greater volume of the seal ring squeezing into the clearance,and under the clearance of 2 mm,the minimum value of the maximum equivalent stress of NBR is 11.418 MPa.Comprehensive consideration of deformation resilience,aging and fatigue rupture suggests that NBR with the hardness of 70 and the clearance of 2 mm can be selected as the material of the seal ring;under this condition,the leak problem of seal rings is solved and its service life is improved.