基于有限元的螺栓法兰接头密封影响因素分析

Analysis of Influencing Factors on Sealing Performance of Bolted Flange Joint by Finite Element Method

螺栓法兰接头在石油化工装置中应用广泛,同时也是主要泄漏源头之一,影响其泄漏的因素较多,由于诸多非线性因素叠加,解析理论分析难度较大。本文基于ANSYS有限元方法,建立了螺栓-法兰-垫片系统模型,仿真分析接头的预紧-工作过程,开展了垫片及螺栓应力分析。研究结果表明,垫片宽度、运行温度和压力对接头密封性能的影响显著。接头密封性能随着垫片宽度的增加而变差,温度对垫片平均应力的影响呈现出非线性特征,内压的增加使得垫片整体应力逐渐变小且引起螺栓应力分布不均匀。

Bolted flanged joint was widely used in petrochemical plants, which was one of the main leakage sources. There were many factors which influence the leakage, and they were interacted with each other. It was of great different for the theoretical analysis by analytical model. In the present paper, finite element model of the bolted flange joint was established to simulate its preloading and loading process. The gasket stress and bolt stress were both analyzed. The results show that gasket width, operation temperature and internal pressure have obvious effect on the sealing performance of the joint. With the gasket width increasing, the sealing performance becomes worse. The effect of operation temperature on gasket stress exhibits nonlinear characteristic. When the internal pressure increases, the whole gasket stress reduces and the bolts stress becomes inhomogeneous.