Effect of External Bending Moment and Creep on Sealing Behavior of Bolted Flanged Connections

A mechanical model based on the tightness of bolted flanged connections subjected to external bending moment was developed by numerical simulation with finite element method (FEM), in which creep and relaxation of bolts, flanges and gasket were taken into consideration. The residual stress distribution of gasket under different operating conditions was obtained. The effect of external bending moment and creep on the tightness of sealing connections was revealed. The FEM results were compared to that of analytical method established on the basis of the former research, and the leakage rate of the connection was predicted. The results obtained by both FEM and analytical method were in good agreement. The research can be used to analyze and assess the tightness of the bolted flanged connections in active service subjected to external bending moment and creep.