Three-Dimensional Contact Stress Analysis for Structural Design of Bolted Joint Assembly of Pressure Vessels in Nuclear Power Plants

원자력 발전소용 압력용기의 볼트 연결 조립부 구조설계를 위한 3차원 접촉 응력 해석

Bolted joint assembly for nuclear power plants consists of various components : cover plate, retainer plate, manway flange, gasket and stud bolts/nuts. To guarantee the soundness of the joint, it is important to prevent leakage through the gasket and reduce the stress concentration factor at the thread root. In this paper, Submodeling technique for the finite element method is proposed to accurately compute three dimensional contact stresses which govern the sealing performance and the maximum contact stresses at the threads root. For verification of global solutions used as boundary conditions of submodel solution, the stresses on the cover plate and the manway flange are measured by strain gages when internal pressure is applied to the bolted joint assembly. The numerical results are compared with the experimental results.