LOWER DEBRIS FILTERING SPACER GRID WITH BLADE SHUTTERS TO PREVENT THE UPGRADE OF FUEL BARS

摘要

A lower spacing grid with a leaf shutter on a spring is disclosed which can filter debris flowing through a channel of a lower end cap with a coolant on the lower end cap of a set of nuclear fuel, and which can prevent the rise of the fuel rods due to the heat transfer fluid, simultaneously. The lower spacer for debris filtering with a blade shutter for preventing the raising of fuel rods, in the spacer grid provided with a band dividing a plurality of single grid cells, and a plurality of springs projecting in uniform directions from each of the horizontal and vertical directions on a grid surface of the web, having uniform resiliency and supporting a lower end cap of a nuclear fuel rod, which includes: a spring having a planar portion with predetermined dimensions for contacting an outer circumference of the lower end cap of the nuclear fuel rod; a blade flap projecting downwardly from the spacer grid at a predetermined angle from the flat portion of the spring; and a curved debris filter member projecting downwardly from the gate surface of the spacer grid.