GB1382797A - Nuclear reactors - Google Patents

Abstract

1382797 Refuelling reactors BRITISH NUCLEAR DESIGN & CONSTRUCTION Ltd 3 Nov 1972 [4 Nov 1971] 51405/71 Heading G6C A nuclear reactor comprises a transfer machine 20 which acts to transfer fuel-elements or other components from core-discharging apparatus to a storage facility and vice versa. The machine 20 is disposed laterally of the core 12 and has a transfer member 22 movable on a pantograph mechanism 21 between or transfer position in which it transfers a component such as a full sub-assembly 32 to or from a respective gripper 18 of a charging machine 16 or 17 (which has been appropriately positioned by rotation of closure plugs 14, 15) and a datum position beneath a gripper 23 for transferring the sub-assembly 32 from or to a careusel 24 to which access may be had, via tube 29, from the exterior of the reactor. The transfer member 22 is constructed to receive a bottom spigot 33 which normally locates the sub-assembly 32 in the core 12, and provides a pad 42 to support the sub-assembly 32 at a slight inclination. The transfer member may be arranged to support two sub-assemblies 32 simultaneously (Fig. 4, not shown) to speed up the refuelling operation by reducing the member of transfer movements. The charging machines 16, 17 may be rotatable relative to the closure plug 15 and may include means to hold down core components adjacent the one being removed. In modifications (Figs. 6 and 7, not shown), the gripper 18 and the transfer member 22 are constructed to provide interference members which coact to prevent, respectively, release of a sub-assembly 32, whose spigot 33 is damaged or missing, from the gripper 18 to the transfer member 22, and movement of the transfer member 22 away from the transfer position until the gripper 18 is fully clear of a fuel subassembly. In the core 12, the sub-assemblies 32 may be disposed at a slight angle to the vertical and supported by leaning posts so as to reduce their vibration due to flow of the sodium coolant.