Abstract: An apparatus and a method for measuring and controlling the crack growth rate within a double cantilever beam type test specimen. The arms of the test specimen are fitted with a pressure-actuated bellows to induce a predetermined load and with a sensing assembly to provide feedback on the amount of beam displacement resulting from application of that load. In this manner a loaded test specimen may be remotely mounted and adjusted inside the reactor pressure vessel or piping of a nuclear reactor in order to maintain a stress intensity which is constant or which varies in a predetermined manner for inducing stress corrosion cracking or corrosion fatigue in the specimen.

Abstract: A stator core for supporting an electrical coil includes a plurality of groups of circumferentially abutting flat laminations which collectively form a bore and perimeter. A plurality of wedges are interposed between the groups, with each wedge having an inner edge and a thicker outer edge. The wedge outer edges abut adjacent ones of the groups to provide a continuous path around the perimeter.

Abstract: A multi-port tool which tests for leaks in the seals of a control rod drive that has been removed from its housing. The fixture is attached to the flange of the control rod drive using quick-release clamps. Two ports of the fixture are respectively coupled to the insert and withdraw ports of the control rod drive. A source of demineralized water at a constant pressure is applied to an inlet port of the leak test fixture. The pressurized water is applied to the control rod drive while the index tube is restrained by a restraining rig. A number of valves are selectively opened or closed to provide a flow path for the pressurized water to either the insert port or the withdraw port. The leakage rate at each of a number of leakage points is determined when the pressurized water is applied at the insert port only and again when the pressurized water is applied at the withdraw port only.

Abstract: An improved system for transferring fuel bundles and control blades between a fuel storage pool and a fuel core of a nuclear reactor. The transfer system includes a carriage which is movable horizontally along a track which is submerged in a transfer pool. The carriage has a slot for receiving interchangeable baskets of different configurations and capacities. One basket is designed to receive a fuel bundle assembly; another basket is designed to receive a control blade. These baskets have the same mounting hardware. The basic construction of the carriage and baskets is aluminum with accessories of stainless steel. Each basket can be hung on the carriage and locked in place with a bolt. Each basket has a bail for handling with existing grapples. When not in use, the baskets are stored and locked in place on a storage rack.

Abstract: An analytical testing means for determining the ion contents of nuclear reactor coolant water comprising ion chromatograph means and a conductivity detector. Reagent containing ion exchange resin is recycled, concentrated and the ion exchange resin regenerated to provide a more economic procedure.

Abstract: A boiling water reactor having a regulating valve for placing the wetwell in flow communication with an intake duct of the passive containment cooling system. This subsystem can be adjusted to maintain the drywell pressure at (or slightly below or above) wetwell pressure after the initial reactor blowdown transient is over. This addition to the PCCS design has the benefit of eliminating or minimizing steam leakage from the drywell to the wetwell in the longer-term post-LOCA time period and also minimizes the temperature difference between drywell and wetwell. This in turn reduces the rate of long-term pressure buildup of the containment, thereby extending the time to reach the design pressure limit.

Abstract: A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling.

Abstract: A method of measuring thin film properties of materials using interference of ultrasonic waves in the frequency range of 2-15 MHz. An ultrasonic interferometer produces interference "fringes" from which the film thickness can be accurately determined. The film may consist of any solid material having known sonic properties and thickness of the order of the sonic wavelength. The device utilizes a narrow-band source of ultrasound and guided-wave propagation to accurately define the optical path of the ultrasonic waves producing the interference. The interferometer is also useful to measure certain material properties in thin specimens, thereby allowing the material to be characterized locally.

Abstract: In a boiling water nuclear reactor fuel bundle, the use of a shortened ferrule spacer in combination with overlying swirl vanes is set forth. In the preferred embodiment, the shortened ferrule spacer is placed under any swirl vanes and has an individual ferrule surrounding each fuel rod at the elevation of the spacer. Each ferrule is given both minimum side wall thickness in the range of 0.020 inches or less as well as reduced height in the order of 0.9 inch or less. The reduced height and thickness of the ferrule spacer is required to maintain pressure drop within acceptable limits and still tends to augment the required liquid film for steam generation over the fuel rod lengths downstream (that is immediately above) the spacer. At the same time, the swirl vane structure is placed immediately above the ferrule spacer overlying the so-called subchannel region of the ferrule spacer between the fuel rods.

Abstract: Electrically controlled load activating mechanisms that can be used inside the containment vessel of a nuclear reactor in conjunction with bellows-loaded DCB crack growth sensors installed inside the reactor pressure vessel or piping of a nuclear reactor. One mechanism is a liquid-filled, double-bellows master/slave arrangement connected by a capillary tube to transmit the loading provided by a linear motion device. Another mechanism uses a heat-resistant gas bottle that can be heated in a furnace to increase the gas pressure to expand the bellows of the DCB sensor. A third mechanism uses a pump or compressor to provide the necessary expansion force. The loading is controlled via electrical connections that do not require special pressure boundary penetrations of the containment vessel.

Abstract: A reactor refueling mechanism includes a bridge, a trolley on the bridge, and an elevator on the trolley, with the elevator including a mast with a grapple at the lower end thereof. The bridge spans a reactor core and is rotatable therearound, with the trolley being translatable over the bridge. The elevator is also rotatable on the trolley, and the mast is vertically movable for positioning of the grapple. The combined movement capability of the mechanism allows the shuffling of fuel bundles between cells in the reactor core, and the accurate placement of square fuel bundles in complementary square cells in the core.

Abstract: The surfaces of a metal or alloy component are scrubbed by a high-velocity stream of inert gas at temperatures which facilitate removal of contaminants. Simultaneous with scrubbing, the impurities are captured in a separated loop of one or more "getter" filters operating at optimized temperatures. The scrubbing and "getting" functions are followed by a rapid elevation of the temperature of the component by heating the inert gas, now essentially free of contaminants which would otherwise react with the component surface at the elevated temperatures. Thereafter, a specific protective layer-forming agent is introduced into the inert gas stream at an ideal temperature, which agent will react predictably with the component being treated to form a predetermined protective coating on its surface.

Abstract: A lock fastener includes a tubular collar having a plurality of protuberances extending radially inwardly from an inner surface thereof and adapted for cooperating with a bolt to retain the collar thereon. A lock ring surrounds an outer surface of the collar and has an initial inner diameter. The lock ring is formed of shape memory metal alloy effective for shrinking the lock ring to a final inner diameter less than the initial inner diameter upon change in temperature thereof to in turn shrink the collar for clamping the protuberances in locking contact with the bolt.

Abstract: A hydraulically based control rod drive system that is contained within the pressure vessel is disclosed for positioning the control rods relative to fuel rods positioned in a nuclear core of a boiling water reactor. Hydraulic jacks mounted on an open grid located entirely within the pressure vessel at a position above the nuclear core are used to position the control rods. Suitable jack and grid structures, as well as a hydraulic control arrangements are described.

Abstract: An all Zircaloy spacer having integral springs and single metallic layer spacer thickness between fuel rods is disclosed. Each spacer cell includes upper and lower octagonal crowns. These octagonal crowns have a full panel height adjoining the defined sub-channel volume between fuel rods and half panel heights adjoining adjacent cells. The crowns at opposite ends of each octagonal spacer cell are designed to interleave to form a single wall thickness of the spacer material. Accordingly, half wall heights at one crown are defined toward the spacer cell while half wall heights at the other crown end are defined away from the spacer cell. By inverting and adjoining the respective spacer cells at their respective crowns, the crowns form upper and lower crown matrices holding adjoining cells of the spacer together. From two adjacent sides of the four sub-channel adjacent full height sides, cell legs extend between the crowns with upper and lower stops immediately adjacent the crowns.

Abstract: A method of manufacturing fuel channels made of zirconium-based alloy by combining heat treatment, warm forming and thermal sizing. Fuel channel strip material is heated to a temperature which initiates the transformation from a hexagonal close-packed to a body-centered cubic crystallographic phase and then quenched at a rate which initiates transformation to a hexagonal close-packed crystallographic phase having a texture factor f.sub.L =0.28-0.38. The heat-treated strips are formed into fuel channel components by bending at an elevated temperature sufficient to increase the ductility of the strip material. After the fuel channel components are welded together, the fuel channel is annealed by thermal sizing.

Abstract: A method for cleaning inlet mixers while they remain in their operating position within a nuclear reactor. A water-powered cleaning tool is inserted by remote control into the inlet mixer via a secondary inlet opening. Following insertion of the cleaning tool, the internal surfaces of the inlet mixer are cleaned with a waterjet created from an ultra-high-pressure source and directed by controlled positioning of a cleaning head having an nozzle which scans the cleaning waterjet across the surface to be cleaned.

Abstract: A removable feedwater sparger assembly includes a sparger having an inlet pipe disposed in flow communication with the outlet end of a supply pipe. A tubular coupling includes an annular band fixedly joined to the sparger inlet pipe and a plurality of fingers extending from the band which are removably joined to a retention flange extending from the supply pipe for maintaining the sparger inlet pipe in flow communication with the supply pipe. The fingers are elastically deflectable for allowing engagement of the sparger inlet pipe with the supply pipe and for disengagement therewith.

Abstract: A nozzle for joining a pool of water to a nuclear reactor pressure vessel includes a tubular body having a proximal end joinable to the pressure vessel and a distal end joinable in flow communication with the pool. The body includes a flow passage therethrough having in serial flow communication a first port at the distal end, a throat spaced axially from the first port, a conical channel extending axially from the throat, and a second port at the proximal end which is joinable in flow communication with the pressure vessel. The inner diameter of the flow passage decreases from the first port to the throat and then increases along the conical channel to the second port. In this way, the conical channel acts as a diverging channel or diffuser in the forward flow direction from the first port to the second port for recovering pressure due to the flow restriction provided by the throat.

Abstract: A pressure suppression system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and an enclosed gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The GDCS pool includes a plenum for receiving through an inlet the non-condensable gas carried with steam from the drywell following a loss-of-coolant accident (LOCA). A condenser is disposed in the GDCS plenum for condensing the steam channeled therein and to trap the non-condensable gas therein. A method of operation includes draining the GDCS pool following the LOCA and channeling steam released into the drywell following the LOCA into the GDCS plenum for cooling along with the non-condensable gas carried therewith for trapping the gas therein.