MULTI-PURPOSE TRANSPORTATION PACKAGE – DESIGN AND LICENSING BY ANALYSIS

Ontario Power Generation (OPG) has designed a new Type B(U) Multi-Purpose Transportation Package (MPTP) that will be capable of transporting radioactive payloads currently handled by two separate packages. The two payloads consist of either a liquid payload (tritiated heavy water) in a special container or a solid payload (contaminated purification media) in a shielded flask. The MPTP is a third generation design that incorporates lessons learned from its predecessors and more than twenty-years of licensing and operating experience with the OPG Type B package fleet. Prior to the MPTP project OPG had designed and licensed its transportation packages using a combination of scalemodel testing and computer analysis. The consistency of the results obtained through these two techniques provided OPG with the confidence to design and license the MPTP by analysis only. Atomic Energy of Canada Ltd (AECL) provided detailed structural and thermal simulations of the MPTP, in both payload configurations, to support OPG’s design and licensing efforts. The simulations addressed impact accident scenarios and the thermal conditions under normal and accident conditions as specified in the Canadian and IAEA regulations. Specifically, the order of postulated accidents is simulated such that the package initially experiences an impact and the damaged package is then subjected to an engulfing fire. Since the package deformation due to accidental impact affects the results of the thermal analysis, the predicted damage is included in the fire accident simulations. The MPTP design and licensing work was successful and OPG received Type B(U) certification of the design in 2006. This paper presents the detailed computer models, describes the simulations, and highlights specific design improvements resulting from the impact and thermal analyses of the MPTP. Also information is provided on the manufacturing and commissioning of the first two MPTPs.