Patent ID: 6847695
Filing Date: 2005-01-25
Classification: G21C,Y02E

Abstract:
1. A nuclear fuel assembly lower tie-plate comprising: a network section having a plurality of holes for receiving end plugs of fuel rods loaded with nuclear fuel so that the fuel rods above the network section are held in a lattice spaced one from the other above the network section, the network section having flow passages between said holes for coolant to flow through; a nozzle section extending downward from a peripheral part of the network section and defining a lower tie-plate cavity below the network section, the nozzle section having an inlet opening at its lower end; a screening plate positioned below the network section in the lower tie-plate cavity, the screening plate being disposed substantially horizontally so that the lower tie-plate cavity is divided into upper and lower cavity parts by the screening plate; and a plurality of tubular filters attached to the screening plate so that the tubular filters each have at least one opening below the screening plate and at least one opening above the screening plate and below the network section; top ends of the tubular filters being closed, and the openings above the screening plate being formed in side walls of the tubular filters, enabling the screening plate and the tubular filters to prevent foreign substances entrained by the coolant from flowing into the upper cavity part of the lower tie-plate cavity bypassing the tubular filter.