Abstract: A support column for a heavy component of a liquid metal fast breeder reactor heat transport system which will deflect when the pipes leading coolant to and from the heavy component expand or contract due to temperature changes includes a vertically disposed pipe, the pipe being connected to the heavy component by two longitudinally spaced cycloidal dovetail joints wherein the distal end of each of the dovetails constitutes a part of the surface of a large diameter cylinder and the centerlines of these large diameter cylinders intersect at right angles and the pipe being supported through two longitudinally spaced cycloidal dovetail joints wherein the distal end of each of the dovetails constitutes a part of the surface of a large diameter cylinder and the centerlines of these large diameter cylinders intersect at right angles, each of the cylindrical surfaces bearing on a flat and horizontal surface.

Abstract: A portable elevated station to be mounted on a tree, including a platform suspended from a hoist. The hoist includes a drum rotatable by handles. The hoist and platform are suspended from a bough of the tree by a rope which is connected to the tree at one end and to the drum near the other end. The drum is rotated by the operator on the platform, to wind or unwind the rope and raise or lower the platform, by the handles. The handles are at an angle of about 90 degrees to each other. There is then, in all angular and elevated positions of the drum, one or more handles available which can be pulled downwardly to wind the rope on the drum and to raise the hoist and platform. The hoist is provided with a latching mechanism including plungers which extend from the ends of the handles, each plunger having a pawl at its outer end. When a handle is rotated at a high speed as the platform drops, the pawl is projected outwardly engaging a plate extending from the frame of the hoist to stop rotation of the drum.

Abstract: A bearing with a lubricant reservoir that is capable of being refilled when the bearing and reservoir are submerged in a lubricant pool. The lubricant reservoir supplies lubricant to the bearing while the bearing allows a small amount of lubricant to leak passed appropriately placed seals creating a positive out flow of lubricant thereby preventing foreign material from entering the bearing.

Abstract: A closure head for a nuclear reactor includes a stationary outer ring integral with the reactor vessel with a first rotatable plug disposed within the stationary outer ring and supported from the stationary outer ring by a bearing assembly. A sealing system is associated with the bearing assembly to seal the annulus defined between the first rotatable plug and the stationary outer ring. The sealing system comprises tubular seal elements disposed in the annulus with load springs contacting the tubular seal elements so as to force the tubular seal elements against the annulus in a manner to seal the annulus. The sealing system also comprises a sealing fluid which is pumped through the annulus and over the tubular seal elements causing the load springs to compress thereby reducing the friction between the tubular seal elements and the rotatable components while maintaining a gas-tight seal therebetween.

Abstract: A nuclear reactor including two rotatable plugs and a positive top core holddown structure. The top core holddown structure is divided into two parts: a small core cover, and a large core cover. The small core cover, and the upper internals associated therewith, are attached to the small rotating plug, and the large core cover, with its associated upper internals, is attached to the large rotating plug. By so splitting the core holddown structures, under-the-plug refueling is accomplished without the necessity of enlarging the reactor pressure vessel to provide a storage space for the core holddown structure during refueling. Additionally, the small and large rotating plugs, and their associated core covers, are arranged such that the separation of the two core covers to permit rotation is accomplished without the installation of complex lifting mechanisms.

Abstract: A nuclear fuel handling grapple carriage having a bearing with a lubricant reservoir that is capable of being refilled when the bearing and reservoir are submerged in a lubricant pool. The lubricant reservoir supplies lubricant to the bearing while the bearing allows a small amount of lubricant to leak passed appropriately placed seals creating a positive out flow of lubricant thereby preventing foreign material from entering the bearing.

Abstract: A system for transferring fuel assemblies between a nuclear reactor core and a fuel storage area while the fuel assemblies remain completely submerged in a continuous body of coolant. The system comprises an in-vessel fuel transfer machine located inside the reactor vessel and an ex-vessel fuel transfer machine located in a fuel storage tank. The in-vessel fuel transfer machine comprises two independently rotatable frames with a pivotable fuel transfer apparatus disposed on the lower rotatable frame. The ex-vessel fuel transfer machine comprises one frame with a pivotable fuel transfer apparatus disposed thereon. The pivotable apparatuses are capable of being aligned with each other to transfer a fuel assembly between the reactor vessel and fuel storage tank while the fuel assembly remains completely submerged in a continuous body of coolant.

Abstract: A lifting, rotating and sealing apparatus for nuclear reactors utilizing rotating plugs above the nuclear reactor core. This apparatus permits rotation of the plugs to provide under the plug refueling of a nuclear core. It also provides a means by which positive top core holddown can be utilized. Both of these operations are accomplished by means of the apparatus lifting the top core holddown structure off the nuclear core while stationary, and maintaining this structure in its elevated position during plug rotation. During both of these operations, the interface between the rotating member and its supporting member is sealingly maintained.

Abstract: A system for transferring fuel assemblies between a fuel transfer area and a fuel storage area while the fuel assemblies remain completely submerged in a continuous body of coolant. A fuel transfer area filled with reactor coolant communicating with the reactor vessel below the reactor coolant level, provides a transfer area for fuel assemblies in transit to and from the reactor vessel. A positioning mechanism comprising at least one rotatable plug disposed on a fuel transfer tank located outside the reactor vessel cooperates with either the fuel transfer area or the fuel storage area to position a fuel assembly in transit. When in position, a transporting mechanism cooperating with the positioning mechanism lifts or lowers a chosen fuel assembly. The transporting mechanism together with the positioning mechanism are capable of transferring a fuel assembly between the fuel transfer area and the fuel storage area.

Abstract: A system for transferring fuel assemblies between a nuclear reactor core and a fuel transfer area while the fuel assemblies remain completely submerged in a continuous body of coolant. The system comprises an in-vessel transfer machine and a valve capable of isolating the reactor vessel from the remainder of the fuel transfer system. The in-vessel transfer machine consists of a positioning mechanism and a lifting mechanism. The positioning mechanism is composed of a plurality of rotatable plugs located on the reactor vessel head. The lifting mechanism which is capable of lifting or lowering a chosen fuel assembly is disposed on a tilted plug at an angle relative to the tilted plug's plane of rotation. The rotatable plugs together with the lifting mechanism are capable of transferring a fuel assembly between the fuel transfer area and any core location or between any two core locations while the fuel assembly remains completely submerged in a continuous body of coolant.

Abstract: An arrangement for the storage of nuclear reactor fuel assemblies having a section wherein fuel is present and a section wherein fuel is not present. The fuel assemblies are placed in a plurality of elongated cells which are joined together to form a cellular structure. The fuel assemblies are placed within the cells at different elevations so that the fuel containing section of one fuel assembly is next to the non-fuel-containing sections of each fuel assembly surrounding the first fuel assembly. The vertical staggering of the fuel containing sections achieves space reductions while maintaining the stored fuel in a subcritical assemblage.

Abstract: A bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing.