非金属密封垫片应力场的数值模拟

Numerical Simulation of Stress Field for the Non-metallic Sealing Gasket

为研究聚四氟乙烯密封垫片的应力分布规律,根据有限元理论,建立了管法兰连接有限元模型。研究了垫片在预紧状态和工作状态下的Von Mises应力和接触应力分布,分析了管道内流体压力、螺栓预紧力和垫片材料弹性模量对其应力值和应力分布的影响。结果发现:垫片在工作状态下的Von Mises应力大于其在预紧状态;流体压力越大,垫片和Von Mises应力越大,但是其有效接触宽度越小;螺栓的预紧力越大,垫片的Von Mises应力和接触应力越大;垫片材料的弹性模量值对垫片接触应力值的影响较小。

To research the stress distribution rule of PTFE sealing gasket, according to the finite element theory, the finite element model of a tube flange connection was established. The distributions of Von Mises stress and contact stress in preloaded state and working state were studied, and the effects of fluid pressure, bolt pre-tightening force and gasket material elastic modulus on the stress value and stress distribution were analyzed. The results showed that the Von Mises stress of the gasket in the working state is greater than that in the preloaded state. Fluid pressure is bigger, the Von Mises stress of the gasket is larger, but the effective contact width is smaller. Bolt pre-tightening force is bigger; Von Mises stress and the contact stress of the gasket are larger. The material elastic modulus has a small effect on the contact stress.