摘要 |
A grid strip (10) for a fuel rod support grid of a nuclear fuel assembly is cold-formed from a flat annealed plate having length, height, and width dimensions. A plurality of slots (12, 14) extend along the height dimension at regular intervals along the length dimension, thereby defining successive cell walls (16, 18, 20) between successive slots along the length dimension. Each cell wall has upper, central and lower regions (28, 30, 32) along the height dimension, each region including a substantially flat base area (34, 36, 38) and fuel rod support structure (22, 24, 26) projecting integrally from the base area along the width dimension of the strip. The support structure in each of the upper and lower regions includes a relatively stiff, arched stop (22, 26) which projects in a first direction and the support structure in the central region includes a relatively soft, arched spring (24) which projects in a second direction opposite the first direction. The spring includes spaced apart pedestals (40, 42) formed in the base area of the central region and projecting in the second direction, and a resilient beam (44) extending between and rigidly supported by the pedestals, so as to project in the second direction beyond the projection of the pedestals. |