Irradiated fuel dry store has bottom charging - of storage shafts with charge machine travelling in air supply chamber

摘要

A dry store for irradiated fuel elements, which are stored in tubes and air-cooled by upward flowing air, has these tubes stacked in vertical shafts of the storage building. A manifold or chamber (8) for the cooling air below these shafts (4) also acts as the charging room in which the charge machine travels and loads the fuel tubes into the shafts above. Pref. the charge machine (20) comprises a lifting mechanism incorporating a spindle, a linkage or toggle mechanism for raising and lowering the (horizontal) storage tubes (1) and has a maximum lifting travel designed for reaching the lowest storage position of a tube (1) in the shaft (4). The shafts pref. possess retaining mechanisms (28,29) for holding the storage tubes in position, more specifically pawls which grip below the storage tubes and co-operate with the charge machine. In particular for the intermediate storage of irradiated fuel elements during the first cooling stage. By arranging the elements horizontal risk of tilting and collapsing of a stack of elements is reduced; furthermore, by the short lift arrangement, the maximum distance through which a storage tube and contained element can fall is approximately equal to the dia. of the tube.