Year
1992
File Attachment
56.PDF2.32 MB
Abstract
About 3000 irradiated Ught Water Reactor (LWR) fuel assemblies are received yearly by COGEMA from their customers throughout the world in the reprocessing plant at LA HAGUE. The fuel assemblies are transported by COGEMA from the French power plants, by Nuclear Transport Umited (NTL) from the other European power plants and by Pacific Nuclear Transport Umited (PNTL) from Japan. Due to the decay heat and activity inherent to the spent fuel content, the shipping casks owned by the transporters are subjected to extensive thermal and containment analysis from the designers for both normal and accident conditions. Thermal analysis aims to demonstrate the compliance of the packages with regard to the transport regulations by fuel decay heat and heat transfer calculations, and by full scale thermal testing. Calculated decay heat and activity limits define the \"working area• of the cask and are quoted in both design safety report and package approval. Staying within these limits ensures the consignor of the compliance with the transport regulations i.e. that accessible surface temperature will not exceed the limit, that fuel cladding damage during transport or unloading, and thus radioactive leakage into the containment systems, will not occur ... Cask over-heating may also affect the life of the seals and the behaviour of temperature-sensitive components such as resin neutron shielding. Apart from just transport considerations, the cask unloading and fuel storage facilities have undergone identical thermal analysis and are designed with their own limits.