FUEL ROD AGGREGATE FOR NUCLEAR REACTOR AND SUPPORT LATTICE

摘要

PURPOSE: To improve the thermal efficiency of a reactor by arranging a supporting lattice a zirconium-based alloy for agitation off contact with fuel rods and fins, or the outer straps of adjacent supporting lattices. CONSTITUTION: A lattice 26 for agitation is constructed of zirconium-based alloy plates 28 and 30 which cross each other and are strengthened in elongation and corrosion resistance under radiation by annealing. Fins 32 are formed downstream (upper part) from the plates 28 and 30, and protruding parts 38 are provided so as not to come into contact with fuel rods 36 which are inserted into the lattice space. The amount of the protrusion of the protruding parts 38 is arranged in a degree that the friction with the fuel rod 36 may allow its moves in up-and-down directions. And the protruding part 38 is horizontally shifted from the center of the plate surface so as not to interfere with the base of the fin 32. With providing the lattice 26 for agitation with no outer straps, its boarder line is arranged to fall within the outline surrounding the whole fuel rods 36 so that the adjacent lattices 26 for agitation of a fuel rod assembly may not come into contact with each other. Other supporting lattices are provided with the fins 32 and protruding parts 38.