Structural Analysis of the Model 9602 Type B Packaging Design for Disused Radiological Sources

A new compact Type B transportation packaging, designated as Model 9602, is being designed by Argonne National Laboratory (Argonne) researchers for storage, transport and disposal of disused radiological sources. This paper describes the mechanical design of Model 9602 packaging, along with the structural analysis performed as part of the preparation of a Safety Analysis Report for Packaging (SARP), which is to be submitted to the regulatory authority for an application of a Certificate of Compliance for the packaging design. The structural performance of Model 9602 under normal conditions of transport (NCT) and hypothetical accidents (HAC) prescribed in Title 10 of the U.S. Code of Federal Regulations (10 CFR 71) Packaging and Transportation of Radioactive Material was evaluated by using the finite element code ABAQUS. The results showed that the packaging design with a full payload endured the most cumulative damage during a 30-ft bottom-down drop, followed by a top-down drop onto a puncture bar, and yet the containment boundary of the cask remained intact, without any damage to the containment vessel (CV) inside, or the internal basket holding the disused radiological sources. These results are significant in that the undamaged configurations of the basket, CV and cask following the 30-ft drop and puncture, will continue to provide thermal protection during the 800oC HAC fire, as well as radiological containment and radiation shielding after the HAC. Thus, the dynamic structural analysis has demonstrated that the structural performance of the Model 9602 packaging design will provide reasonable assurance that the regulatory requirements of 10 CFR 71 have been met. Moreover, the all stainless-steel packaging design of Model 9602 should provide excellent performance against general corrosion during long-term storage, thus enabling subsequent transportation, without repackaging of the disused radiological sources, to a repository or deep borehole for final disposal.