Three-Dimentional Finite Element Analysis for Bolted Flange Joint Structure of Primary Manway of Steam Generator

Three-dimentional finite element model for bolted flange joint structure of primary manway of steam generator was built considering temperature lag of the bolt, turning angle of the flange and contact between gasket and the flange, nut and the cover. Transient analysis was carried out under normal and upset conditions. Problem of air heat trsfer in the bolt hole and between the cover and the flange were solved. Bolt pretension load was applied, and the change of the bolt load was obtained along with the time. Mechanical and heat haracterics of the joint structure was simulated. Leaktightness was validated and fatigue stress and displacement of the joint structure were estimated according to regulations.