Patent ID: 8243872
Filing Date: 2012-08-14
Classification: G21C,Y02E

Abstract:
1. A spacer grid assembly for dual cooled nuclear fuel rods, comprising a plurality of unit grid straps defining spaces for the dual cooled nuclear fuel rods, wherein each of the unit grid straps has supports including cantilever leaf springs for supporting each of the dual cooled nuclear fuel rods set in an array and has a sheet shape, wherein each unit grid strap has a front side which defines a portion of one space for a dual cooled nuclear fuel rod, and a rear side which defines a portion of an adjacent space for a dual cooled nuclear fuel rod, the supports being located at positions shifted from a longitudinal central line of each unit grid strap toward corners defined by intersecting unit grid straps, wherein the cantilever leaf springs are formed on the front and the rear sides of each unit grid strap in symmetry based on the longitudinal central line of the unit grid strap, wherein each cantilever leaf spring includes a protrusion which protrudes from the unit grid strap toward the dual cooled nuclear fuel rod, and an extension which extends from the protrusion so as to enclose an outer circumference of the dual cooled nuclear fuel rod, wherein the extension has a curvature prior to insertion of the dual cooled nuclear fuel rods which is equal to that of the outer circumference of the dual cooled nuclear fuel rod.