GROUP OF NUCLEAR FUEL FOR NUCLEAR REACTOR

The group contains an aggregate of fuel cells (1) vertically arranged in a construction composed of distancing grids (2) fixed to tubular channels (3), on whose overlapping ends there is an end piece (4) and on whose upper ends there is a removable head (5) attached by remote controlled equipment, and which is composed of a lower plate (6) and upper plate (8) equipped with holes (7, 9). These plates (6, 8) are attached by the holes (7, 9) to guide sleeves (11). At one end of the guide sleeves (11) there are longitudinal indentations (19) and annular grooves (32), ensuring the possibility of separating the connection of the head (5) with the tubular channels (3), whereas the guide sleeves (11) are connected to the upper ends of the tubular channels (3) projecting from the aggregate of fuel cells (1) and they rest on the front side (34) of the tubular channels (3) by their inner recess (31). The group also contains springs (10) arranged on the guide sleeves (11) between the upper and lower plates (6, 8), a lower buffer (16) to prevent loosening of spring (10) pressure in a downwards direction, an upper buffer (17) to prevent loosening of spring (10) in a upwards direction, which is arranged on the guide sleeves (11) above the upper plate (8), and a restrictor (24) of downward movement of the lower plate (6). At their lower ends the guide sleeves (11) are connected with the upper end of the tubular channels (3), equipped with longitudinal indentations (19) and internal annular grooves (32), whereas the upper buffer (17), limiting loosening of spring pressure upwards, is firmly fixed to the upper end of the guide sleeves (11). The cluster also includes a tabular stop device (12) firmly fixed to the lower plate (6) and equipped with holes (18) which are fitted to the lower ends of the guide sleeves (11) with longitudinal indentations (19) and annular grooves (32) embracing the collars (25) of the tubular channels (3).