Abstract: A shipping device for a heater unit assembly (23), the heater unit assembly (23) including a cylindrical wall (25) and a top plate (31) secured to the cylindrical wall (25) and having a flange portion which projects radially beyond the outer surface of the cylindrical wall (25), and the shipping device including: a cylindrical container (3) having a closed bottom (13); a support member (47) secured to the container (3) and having an inwardly directed flange for supporting the flange portion of the top plate (31); a supplemental supporting system (1) for positioning the heater unit assembly (23) in the container (3) at a spaced relation from the inner surface and bottom wall (13) of the container (3); a cover (15) for closing the top of the container (3); and a container supporting structure (5,7,8) supporting the container (3) in a manner to permit the container (3) to be moved, relative to the supporting structure (5,7,8 ), between a vertical position for loading and unloading the assembly (23) and a horizon

Abstract: A support system is provided for a pressurizer relief and safety valve system in a nuclear power plant. The pressurizer has a generally cylindrical vessel wall topped with a dome-like member. The valve system includes a manifold generally located above and extending about the periphery of the vessel wall of the pressurizer.The valve support system comprises a plurality of paired lug members that extend outwardly from and are secured to the vessel wall at points spaced around the wall periphery. V-shaped columnar supports extend vertically upward from each of the lug pairs to the valve system manifold.A structural pin extends in the horizontal direction to support a base portion of each of the columnar supports relative to the associated lug pair. Disengageable locking clamps secure the pin to the lugs. A pair of diagonal columns extend upwardly in a V-shape from the support base portion to the manifold. A crossbar connects the diagonal columns at the top of each columnar support.

Abstract: A system for annealing a vessel (14) in situ by heating the vessel (14) to a defined temperature, composed of: an electrically operated heater assembly (10) insertable into the vessel (14) for heating the vessel (14) to the defined temperature; temperature monitoring components positioned relative to the heater assembly (10) for monitoring the temperature of the vessel (14); a controllable electric power supply unit (32-60) for supplying electric power required by the heater assembly (10); a control unit (80-86) for controlling the power supplied by the power supply unit (32-60); a first vehicle (2) containing the power supply unit (32-60); a second vehicle (4) containing the control unit (80-86); power conductors (18,22) connectable between the power supply unit (32-60) and the heater unit (10) for delivering the power supplied by the power supply unit (32-60) to the heater assembly (10); signal conductors (20,24) connectable between the temperature monitoring components and the control unit (80-86) for deli

Abstract: A HP/LP seal arrangement is provided for a guide tube and thimble extending outwardly from the core of a nuclear reactor to a seal table where the guide tube is welded to the seal table to provide a high pressure seal relative thereto. A tubular seal fitting is disposed in alignment with the guide tube with the thimble extending therethrough on the low pressure side of the seal table.A first high pressure seal couples one end of the fitting to an end of the guide tube to prevent leakage from within the guide tube. Inwardly facing threading is disposed adjacent the other and outer end of the seal fitting. A nut is disposed about the thimble and it is provided with outwardly facing threading in mating engagement with the fitting threading.The fitting has a seal seat spaced longitudinally inwardly from the threading and facing the fitting outer end and extending annularly about the inner surface of the fitting.

Abstract: A reactor vessel O-ring spring clip designed to hold the tubular O-ring in the groove of a reactor vessel head flange, especially during head lifting. The spring clip is designed such that the weight of the O-ring acts to increase the friction force between the spring clip and the, typically, threaded hole into which it is inserted. The end of the clip adapted to be inserted through a slot in the tubular O-ring for securement thereto has a circular member thereon which prevents the spring clip from becoming disengaged from the O-ring during head lifting.

Abstract: A nuclear reactor having a remotely removable and replaceable thermal insulating shield for the head. Access permitting removal and replacement of the head is thus afforded.The thermal insulating shield includes a vertical frame of insulating material of polygonal transverse cross section encircling the head. A top panel of insulating material is mounted on the top of the frame pivotal by remote actuation between a horizontal position and a retracted position which may be vertical. In the horizontal position, the panels mate to provide thermal shielding for the head.

Abstract: A self-adjustable supplementary support system for a cylindrical container coaxially disposed in a cylindrical housing by upper flanged supports has a plurality of outwardly extending bracket units on the external surface of the container which coact with inwardly extending resiliently outwardly extending bracket units on the inner wall of the cylindrical housing. The bracket units have flanges which form a concave surface that seats on support bars, attached by links to torsion bars that are secured to ring segments annularly spaced about the inner wall of the cylindrical housing and the bracket units and support bars coact with each other to radially position and support the container in the housing during movement of the two components from a vertical to a horizontal position, and during transportation of the same.

Abstract: An improved nuclear reactor wherein the bolted connections between the baffle plates and baffle former and the baffle former and the core barrel are provided with a noval locking device that prevents loosening of the bolted connections. The locking device to prevent loosening of bolted connections where a threaded bolt is used to secure two components together uses a threaded lock nut over the bolt head, cooperative with a threaded wall in a recess in a component. The lock nut and wall of the recess have threads opposite the threads of the bolt. Deformable sections are formed in the base of the lock nut to engage an unsymmetrical cavity in the head of the bolt. Turning of the bolt in a direction that would tend to loosen the connection causes tightening of the lock nut. The wall of the lock nut may be threadedly engaged with the wall of the recess or the lock nut wall may have slits formed thereon which enable deformation of wall portions to engage the threaded wall of the recess.

Abstract: A guide tube flow restrictor for use on an upper guide tube housing support plate of a nuclear reactor, for guiding of a control rod drive shaft through an aperture in the support plate and restriction of flow of coolant therethrough, has an outer ring seatable on the support plate, the outer ring having a flange member from which there depends a plurality of flexible members, the flexible members having inwardly disposed deflectors thereon, and extending through the bore of the outer ring and the aperture of the support plate. An axially insertable sleeve, upon insertion into the outer ring, between the flexible members, contacts the deflectors thereon to radially force the flexible members outwardly to secure the same with the walls of the aperture of the support plate. Baffles are provided on the flexible segments and additional locking members provided between the outer ring and inner sleeve.

Abstract: The lower end of a nuclear reactor core barrel (16) is laterally stabilized within the reactor pressure vessel (10) by four auxiliary support structures (100) equiangularly disposed about the periphery of the reactor lower hemispherical shell (12). The core barrel lower support plate (18) has keys (122) secured thereto for disposition within recesses (114) defined within crossbeams (102) of the structures (100) through which horizontal radial and tangential forces, as well as severe vertical loads, are transmitted from the core barrel (16) to the reactor vessel (10). Shock absorbers (120) interconnect the keys (122) and the crossbeams (102), and divergent brackets (104) serve to radially space the crossbeam (102) from the shell wall (12) so as to define a vertical coolant flow channel (108) through each structure (100).

Abstract: A support structure for supporting a pressurizer safety and relief valve system above a pressurizer vessel comprises a ring girder which surrounds the pressurizer vessel wall and is supported on pairs of lugs spaced about the pressurizer wall. The ring girder supports columns for the system at locations spaced from the lugs, and support means in the form of frames distribute the load on the lugs. The frames have upper and lower bars and outer vertical bars, with spaced inner vertical bars. Biasing means are provided to attach the frames to the lugs and distribute the forces, and a projection on the ring girder fits into a groove of a support bar on the upper bar of the frame.

Abstract: A support system for supporting a pressurizer safety and relief valve system above a pressurizer vessel of a pressurized water reactor, which comprises an upper ring section that rests on the dome of the pressurizer, a lower ring section having sleeves attached thereto, and a plurality of arcuate connecting sections, conforming to the shape of the dome. Columnar supports for the valve system are supported in the sleeves on the lower ring and collars are attached to the arcuate sections stabilize the columnar supports.

Abstract: A nuclear reactor having a remotely removeable and replaceable thermal and/or radiation insulating shield for the head. This shield is formed of interlocked integrated shielding units of thermal insulating material. Each unit has a vertical member and a horizontal member. Each unit has a lifting-and-lowering rod on its top and it may be raised vertically by a remotely operable clamp engaging the head. The interlocking surfaces of adjacent units are so formed that when any unit is raised or lowered vertically its interlocking surface readily slides along the interlocking surfaces of the units adjacent to it with which it is interlocked.