FUEL ASSEMBLY AND FUEL CHANNEL BOX

摘要

PROBLEM TO BE SOLVED: To provide a fuel channel box and a fuel assembly that reduces the effective, maximum amount of expansion while the fuel channel box corresponding to the high degree of combustion of fuel is being used and can be coped with by conventional manufacturing technics by limiting both the initial thickness and the usage maximum degree of combustion of a fuel channel box. SOLUTION: When uniform thickness is set to (t) and the distance of the facing inner surfaces of the fuel channel box is set to L on the cross section of a central part excluding upper and lower end parts in the fuel channel box in this fuel assembly for boiling light-water reactors where the degree of the maximum usage combustion is within a range from 55 GWd/t to 100 GWd/t, the fuel channel box for satisfying the conditions of 0.0235<=(t/L)<=0.0268 is used.