KE Basin monorail modification for the sludge removal and packaging project

摘要

The 105KE Basin currently stores over 1,100 metric tons of various N Reactor spent fuel in several canister forms, as well as several metric tons of sludge which must be removed. Modifications will consist of anchoring a permanent steel frame directly into the pit walls between existing columns and adding two travelling hoist rails, each capable of two directional motions. Each pit will have its own capability for targeting loads to any point inside the working areas of these pits. The structural frame designed for the monorail system at the Weasel and Tech-View pits was qualified as adequate for normal/operating loads, and dead plus live loads combined with seismic loads. The hoist operating live load is limited to 2,000 lb. The physical strength of the existing pit walls where the base plates are to be structurally anchored is unknown. The original structural drawings specified a minimum concrete strength of 3,000 lb/in(sup 2). A pullout test should be performed to verify the strength of this concrete base. To reduce radiation exposure to levels as low as reasonably achievable (ALARA), installation and erection work inside the basin controlled area must be minimized; therefore, the pieces required for the modifications should be numbered in the fabrication shop, and erection should follow a procedure that corresponds to the assembly sequence indicated by the numbers. In conjunction with final erection, a mock-up activity should be conducted and base-plate locations verified to be within dimensional tolerances.