Selection of cask shell material

Previous cask design experience indicates that the stress analysis and structural stability evaluation of the cask inner shell is a key factor in evaluating the adequacy of the cask's containment boundary. The yield strength of the shell material establishes the thickness required and, hence, the cask weight, which indirectly controls the cask capacity. This study concentrates on the effect of different materials and different shell thickness combinations on the cask capacity. Nuclear Assurance Corporation used the ANSYS finite element structural analysis code to perform a detailed structural analysis of an existing rail/barge cask. The cask's capacity is 31 assemblies in a burnup credit configuration. The stress results for the inner shell obtained from the ANSYS analysis are used for the buckling evaluation in accordance with the American Society of Mechanical Engineers (ASME) Code Case N-284 to determine the adequacy of the inner shell thickness. 2 refs., 1 fig., 5 tabs.