Safety Margin Characterization for In-Service Pressure Vessels Containing Crack Defects

Abstract

It’s significant and necessary to assess the safety of the in-service pressure vessels containing crack defects, and there are so many methods that can do, for example, the finite element method and probabilistic fracture mechanics assessment method. However, knowing the safety of the pressure vessels containing crack defects is not enough. For the residual lifetime reason, we are eager to get the safety margin of the pressure vessels. That is how secure they are. Aiming at this problem, we put forward the concept of failure path based on the Failure Assessment Diagram (FAD) and fracture mechanics to help to characterize safety margin. Facts proved that this method was original and useful which can provide a new way in solving the residual lifetime assessment problem of the in-service pressure vessels containing crack defects.