Life prediction of reprocessing (CORAL) components

The purpose of Compact Facility for Reprocessing of Advanced Fuels in Lead cell (CORAL) is for reprocessing of irradiated fuel. Towards arriving at life of CORAL, various critical components like titanium dissolvers, reflux condenser, waste storage tank and process tanks in the facility have been identified and analyzed for pressure and thermal loadings. All these components are operating below 126° C and hence there is no concern of creep damage. However, the junctions are subjected to cyclic thermal loadings which may restrict the design life. Moreover the various parts of the components such as tube and shell can have differential expansion leading to thermal stresses which along with stress concentration can restrict the fatigue life of the components. The stress analyses of all the critical components are carried out using Finite Element Software CAST3M, issued by CEA, France. The fatigue damage evaluation has been done as per the French design code RCC-MR 2002. It has been demonstrated that low cycle fatigue is not a major concern and the life of thin parts are governed by corrosion considerations. A small nozzle (8 NB) in the dissolver is found to govern the design life from corrosion consideration. The analyses, apart from helping to identify critical locations of various parts and design life of various mechanical components, also focused the importance of corrosion as the governing failure mode.