Development of Spent-Fuel Transport and Storage Dry Casks

Many nuclear power plants are running out of storage space in their reactor pools for storing spent fuel. On-site spent fuel storage in metal casks to store excess spent-fuel elements is now being in the stage of practical application in Japan. Mitsubishi Heavy Industries, Ltd. has developed a transportable dry storage cask \"MSF-V\" to carry high bum up spent-fuel. This paper describes an outline of the MSF-V -26P transport and storage cask to contain 26 PWR fuel elements, which is designed to meet practical requirements derived from the site handling operations. Design characteristics of the cask are Increasing number of fuel elements accommodated in the cask taking into account the existing cask handling equipment capability and allowable extended cooling period for spent fuel. Designed in conformity with the domestic safety standards for spent-fuel storage in metal cask established by the Japanese Competent Authority. A multilayer structure (steel-lead-steel-resin) optimized shielding thickness for neutron and gamma attenuation. Original basket design and the multilayer shielding system provide minimum cask diameter with maximum fuel accommodations.