NUCLEAR REACTOR INTERNAL BLOCK Russian patent published in 2002 - IPC

FIELD: water-cooled nuclear reactors for low-power nuclear power plants. SUBSTANCE: internal block has ferrule with top, intermediate, and bottom perforated plates attached to it; absorbing safety rods disposed in space between fuel assemblies passed through holes in intermediate plate and integrated by means of yokes moving in guides mounted between top and intermediate plates; bottom ends of rods are locked in perforated sheet attached to them in a spaced relation within joints; these sheets move together with rods between intermediate and bottom plates over at least two tubes mounted in-between for replacement during reactor refueling. EFFECT: enhanced reliability, extended service life. 3 cl, 4 dwg