Patent Number: 040627241
Section: claims

1. A nuclear reactor construction comprising a vessel containing a pool of liquid coolant, a reactor core submerged in the pool of coolant, a collecting tray for core debris submerged in the pool of coolant below the core and spaced from the floor of the vessel, an internal skirt attached to the wall of the vessel and overlapping the periphery of the tray to direct core debris into the tray,  the collecting tray comprising a complex of cooling tubes extending between a base plate of the tray and a peripheral wall of the tray, the base plate forming a plane tube sheet in which one open end of each cooling tube is received and the peripheral wall forming an annular tube sheet in which the other open end of each cooling tube is received, the tube connections with the plane tube sheet being arranged on concentric pitch circles and the tube connections with the annular tube sheet being arranged in layers thereby to effect a regular distribution of cooling tubes throughout the tray.  a vertical inner annular wall,  a conical portion surmounting the inner wall and  disposed with axis on the vertical axis of the  reactor core, and  an outwardly directed inclined upper extension of the peripheral wall. 2. A nuclear reactor construction according to claim 1 wherein the base plate of the collecting tray is annular and has