Abstract: Apparatus (16) for gripping the inner surface of a plug (14) so that it can be removed from a tube (12). The apparatus includes a shaft (18) having an enlarged frustoconical head (20) with a collar member (24) surrounding the shaft. The collar has a plurality of flexible fingers (22) extending up therefrom, which are forced radially outwardly into contact with the inner wall of the plug when the head is moved longitudinally outwardly from the plug. Each finger has an end portion which is tapered and forms first (10 degrees) and second (5 degrees) angles on its inner (32) and outer (30) surfaces, respectively; and the frustoconical surface (34) of the enlarged head forms a third angle (15 degrees), with the sum of the first and second angles being equal to the third angle. The end portions of the fingers are thus moved radially outwardly, such that their outer surface lies parallel with the inner surface of the plug and thus, the plug is gripped over a large surface area by the gripping mechanism.

Abstract: A tool (78) for grasping a multiplicity of nuclear fuel rods (42) to remove them from a nuclear fuel assembly (32) and relocate them, preferably, into a fuel consolidation device (86). The tool has a gripper head (200) reciprocably guided within a shroud (80). A distinct jaw mechanism (216) for grasping each of the multiplicity of fuel rods is carried by a common frame (214) and actuated and controlled by a distinct means (232, 234, 242). A key feature of the gripper head is that each jaw mechanism (216) has an neck portion (244) to offset the actuation means (232, 234) from the moving jaw portion (220). The shroud carries alignment means (82, 206) for precisely orienting the tool relative to a targeted group of rods within the assembly, so that the spacing of the rods is maintained as they are pulled up into the shroud by the gripper head.

Abstract: A nozzle between the nuclear steam generator and nuclear reactor vessel has a dam, plug, or barrier mounted on the tapering internal wall of the conduit. A seating ring is mounted on the tapered internal surface of the nozzle through screws which will ensure release of the ring after pressure on the dam is removed, and the screws are backed away from engagement with the tapered surface.

Abstract: A hydraulic actuator (26) for removing a plug (14) from a tube (12) including tube gripping means (28, 32), the actuator having a double piston arrangement (38, 52), which when energized quickly and efficiently first causes the gripping means to positively grip the plug, and then thereafter remove the plug from the tube, all in one continuous motion.

Abstract: A fluid-filled network of connected conduits and valves receives an acoustic signal in the form of waves of predetermined frequency, amplitude, and time sequence. At a second location, an acoustic receiver senses the form of the waves in frequency, amplitude, and time sequence arriving from the transmitter. The comparison between the acoustic signal introduced into the network and the signal received from the network represents whether the valve settings are satisfactory for using the network as a unit.

Abstract: A laminar diaphragm (16) for use in a pressure transducer (10) comprised of two or more layers (50, 52, 54). The pressure boundary membrane (50) free of machining defects is supported by one or more support members (52, 54) having a fluid passage therethrough (56, 58). The support members (52, 54) are hermetically sealed around the periphery of fluid passages (56, 58) to the pressure boundary membrane (50) such that when the laminar diaphragm (16) is sealed in the pressure transducer (10) deflection of the pressure boundary membrane (50) within the regions of fluid passage (56, 58) in support members (50, 52) accurately indicates pressure.

Abstract: A clamp for use with a quick-disconnect cable connector for joining a cable connector having a plug assembly and matching receptacle. A coupling sleeve is axially passed over the plug assembly. A mating coupling sleeve is secured to the coupling nut portion of the plug assembly with an axial force transmitting device therebetween. The axial force transmitting means transmits an axial force developed when the two coupling sleeves are torqued to the plug assembly. The axial force transmitted means may be cylindrical sectors for a slotted annular ring with the result that the axial force is distributed uniformly around the plug assembly such that the plug assembly is seated against the receptacle maintaining a seal therebetween and preventing misalignment.

Abstract: A control rod testing apparatus with a testing subassembly (30) floatingly secured in a guide structure (20, 48, 50). Two centering means (64, 76) center the subassembly (30) around the rod being tested. Pancake coils (72) sense the proximity of sensing fingers (82) which side against the periphery of the rod being tested for the purpose of determining the geometry of the rod.

Abstract: Apparatus and method are disclosed for continually generating data values (M) indicative of the time dependent waveform of the current (I.sub.C) in a control rod latch actuation circuit (28), during application of a pulsed drive voltage (30). A data value is selected that represents a value limit (M.sub.min) characteristic of the waveform during the time before the latch (14) has reached a critical position of interest. The most recently generated data value (M.sub.N) is compared to the value limit (M.sub.min), and a control signal (e.g., 74, 52, LH) is generated when the most recently generated data value (M.sub.N) exceeds the value limit (M.sub.min). The data values (M) preferably indicate the time derivative of the waveform (I.sub.C) at a plurality of predetermined times during application of the drive voltage.

Abstract: A motorized transporter is placed at the periphery of the tube bundle which extends up from the tube sheet within a nuclear steam generator shell. The transporter can be separated into parts as required to move it into and out of the limited space between the tube bundle and inside wall of the generator. A control station external the generator is connected by flexible cables to the transporter and its equipment in order to move the transporter, observe the transporter path for foreign objects, and retrieve such objects.

Abstract: A grid structure (42) is mounted within the upper portion (24) of a tapered canister (24), for receiving a relatively loosely packed rectangular array of rods (22) and rearranging the rods into a relatively tightly packed rectangular array at the lower end of the grid. The grid structure comprises a multiplicity of flat, vertically oriented trapezoidal segments (78, 80) interconnected to form a plurality of vertically overlapping grid layers (74, 76). The layers alternate between a row orientation and a column orientation, and thus form a substantially continuous honeycomb of longitudinal cells (64) for guiding individual rods. The cross-sectional area of each cell decreases from the uppermost layer (74a) to the lowermost layer (74i) such that the rods are funneled by the cells to form the tightly packed array.

Abstract: A connector device to provide a primary pressure boundary between a flanged nozzle (18) and a column (20) concentrically disposed therein, including a closure member (26) for compressing a seal ring (22) against the nozzle flange (18). The closure member (26) includes a hub portion (34) defining an annular space (36) between the closure member and the column. Graphite gasket rings (40) are inserted into the annular space (36), and drive unit including a sleeve (42) actuator nut (50), and collar (54) is attached to the column at the collar location. Actuation of the nut (50) against the collar (54) draws the column (20) into rigid engagement with the closure member (26), and then advances the drive sleeve (42) along the annular space (36) to compress the gasket ring (40), thereby completing the fluid-tight connection.

Abstract: A control rod for a nuclear fuel assembly has structures formed of boron carbide mounted inside it. The boron carbide structures are provided deformable members between them which will deform at operating temperatures to accommodate the dimensional increase of the boron carbide structures and reduce the level of deformable stress on the rod cladding.

Abstract: A nuclear reactor vessel has an electromagnet positioned within to generate the predetermined temperature for the vessel wall for a predetermined time to anneal the vessel.

Abstract: An elongated canister (86) into which the fuel rods (42) from, preferably, two nuclear fuel assemblies (32) are inserted from above, and then passively consolidated within the canister such that at the lower end (88) the effective density of the rods is approximately double that of each fuel assembly. The canister includes a straight vertical back panel (308), side panels (312) having straight upper (310) and inwardly oriented, tapered lower portions (314), and a front panel (300) having straight upper (302) and tapered lower (304) portions. Spaced apart plates (90) extending between the front and back panels, and a temporary base (320), preferably titled from front to back, in conjunction with the generally funnel-shaped canister, operate to urge the rods close together while the rod pattern is transformed from square to triangular pitch.

Abstract: A neutron streaming shield comprising a plurality of wire mesh baskets, each basket located between two adjacent vessel nozzles, the total area of the nozzles and baskets being sufficient to intercept any streaming neutrons. The baskets are substantially filled with a multiplicity of randomly packed lumps of a neutron attenuating material, preferably a borated-hydrogenated-argillaceous media. Since the basket is somewhat flexible, it can be inserted in the annulus above the nozzles and then filled with the lumped material, forming a plurality of barriers to compliment the attenuating affect of the nozzles, such that any streaming neutrons will be stopped either by the nozzles or the lumped material in the baskets.

Abstract: A canister for the consolidation of nuclear fuel rods (22) comprises an elongated, tapered box (24) of generally rectangular cross-section having upper (42) and lower (44) internal sections, the upper section having rectangular grid structure (46) and the lower section having vertically extending plate members (48). The upper section receives individual fuel rods in a relatively loosely packed rectangular array of rows and columns and urges the rods closer together as they are lowered into the box, such that the rods emerge through the lower end of the grid section in a relatively tightly rectangular array. The number of plate members (48) in the lower section corresponds to the number of rows of fuel rods in the upper section. Each plate has tapered side edges (204) abutting the tapered box, and a plurality of integrally formed, corrugated channels (206) corresponding to the number of rows of fuel rods.

Abstract: A gripper device (24) for attachment to the inside of a tube (12) has a shaft member (26) including an upper tapered portion (30) surrounded by a generally cylindrical sleeve member (34) having at least two holes (38) opposite the tapered portion of the shaft. The sleeve outer diameter is slightly less than the inner diameter of the tube targeted for attachment. A spring (32) is connected between the shaft member and the sleeve member, for biasing the tapered shaft downwardly relative to the sleeve. A round bearing or hard ball (36) is located in each hole such that downward motion of the shaft relative to the sleeve urges the balls outwardly to protrude from the sleeve surface against the tube wall. The device is installed by pushing on stem (28) at the lower end of the shaft member to insert the device into the tube. A flange (44) is formed at the lower end of the sleeve to limit the sleeve insertion into the tube.

Abstract: A system and method for handling nuclear fuel in which a consolidation stage (26), including a disassembly station (60), an interim transfer station (62) and a consolidation station (64), and a multiple rod pulling tool (78) and interim fuel transfer canister (86) are employed to remove fuel rods (42) from two fuel assemblies (32) and consolidate them into one storage box (96). A key feature of the disclosure is the alignment of the transfer canister (86) over the box (96) such that the canister base (92) with the weight of the consolidated rods, is released and lowered into a new position as the base of the storage box (96). A duel elevator arrangement (108, 110) is disclosed for moving the base (29) and box (96) to transfer the rods therebetween.

Abstract: A wrench for removing and installing cylindrical retainers, particular sight glass retainers comprises a base member, a guide member and a pair of projections. The base member has a planar stop surface on one axial end. The guide member is fixed to the base member and extends perpendicularly from the stop surface. The projections extend in opposite directions from the guide member parallel to and over the stop surface. When coupled to a sight glass retainer, the stop surface engages an exposed axial end portion of the retainer, the guide member engages the retainer inner cylindrical surface, and the projections are received within diametrically opposite recesses in the retainer end portion.