Elastic and Plastic Analysis of O-Ring Seal for Reactor Pressure Vessel

Abstract

The elasto-plastic analysis for Reactor Pressure Vessel seal is necessary because of nuclear safety is actively demanded. The existed work based on simplified way to simulate the seal ring, such as uniform stress, spring elements, is too conservative. Therefore, it is necessary to simulate seal ring using 3D solid model considering the elasto-plastc deformation. In this paper, the two-dimensional model is adopted to simulate the compressing and springback character of inconel 718 O-ring using nonlinear isotropic hardening constitutive model and contact algorithm. The simulation approach and constitutive model are validated according to the deformation of seal ring using ANSYS. The seal analysis for reactor pressure vessel is achieved by considering complex loads, such as bolt pre-tightening force and temperature/pressure transient with the usage of an elasto-plastic constitutive model. It is found that the deformation of seal ring obtained by finite element is close to true value. The application of 3D solid model can reduce excessive conservatism effectively and improve the precision of seal analysis compare to the simplified method.