Abstract: Methods and apparatus for examining a nuclear reactor shroud are described. In one embodiment the inspection apparatus includes an elongate tubular upper section, an elongate middle section, an elongate lower section, and a scanner arm assembly movably coupled to the middle section. The inspection apparatus is configured to be inserted into the reactor pressure vessel through one of the openings in the reactor core plate. The upper section includes a bail handle and an indexing ring having an alignment lug, a plurality of slots and a movable locking tab configured to engage the slots. The lower section includes a rotary bearing located at the bottom end. The lower section is configured to engage and rest on a control rod drive housing. The middle section includes a movable door and a movable traveler plate movably coupled to the scanner arm assembly. The scanner arm assembly includes a fixed track, a movable track, a scanner carriage, and a scanner array.

Abstract: A process management expert system where following malfunctioning of a component, such as a pump, for determining system realignment procedures such as for by-passing the malfunctioning component with on-line speeds to maintain operation of the process at full or partial capacity or to provide safe shut down of the system while isolating the malfunctioning component. The expert system uses thermal-hydraulic function classes at the component level for analyzing unanticipated as well as anticipated component malfunctions to provide recommended sequences of operator actions. Each component is classified according to its thermal-hydraulic function, and the generic and component-specific characteristics for that function. Using the diagnosis of the malfunctioning component and its thermal hydraulic class, the expert system analysis is carried out using generic thermal-hydraulic first principles.

Abstract: The present invention provides a method and apparatus for fuel handling in a nuclear reactor. The nuclear reactor has a reactor vessel comprising a reactor core with a plurality of fuel assemblies and control rods. A fuel pool is arranged adjacent to the reactor vessel. A group comprising at least a plurality of fuel assemblies is simultaneously lifted out of or into the reactor vessel with a single gripper, the gripper having a plurality of gripping devices. The group is transported between the reactor vessel and the fuel pool by means of the gripper.

Abstract: This invention provides coded aperture imaging apparatus and methods for the detection and imaging of radiation which results from nuclear interrogation of a target object. The apparatus includes: 1) a radiation detector for detecting at least a portion of the radiation emitted by the object in response to nuclear excitation and for producing detection signals responsive to the radiation; 2) a coded aperture disposed between the detector and the object such that emitted radiation is detected by the detector after passage through the coded aperture; and 3) a data processor for characterizing the object based upon the detection signals from the detector and upon the configuration of the coded aperture.

Abstract: An integrated head assembly for a nuclear reactor pressure vessel includes a closure head with CRDM assemblies extending upwardly from the head. A CRDM seismic support disposed above the closure head provides lateral support for the CRDM assemblies. The seismic support also has air flow holes which communicate with the interior of a shroud enclosing the CRDMs and extending upwardly from the closure head to the seismic support. The shroud has an air port in direct air flow communication with the surrounding atmosphere so that the closure head, shroud and seismic support define an air flow passageway directly communicating with the surrounding atmosphere via the air port and without the extensive ductwork and, therefore, with substantially less power. A missile shield disposed above and in air flow communication with the seismic support provides a lightweight, compact physical barrier for removing energy from dislocated objects such as CRDM drive rods.

Abstract: A power range monitor apparatus includes a plurality of average power range monitors for calculating/monitoring local power values, average reactor power values, and core flow rate values, a plurality of rod block monitors for monitoring the average values of local power values, and a plurality of flow rate signal converters for converting the signal form of recirculation rate detection signals. The flow rate signal converters concurrently transmit recirculation rate detection signals as digital signals to the average power range monitors. The average power range monitors obtain core flow rate signals from the respective recirculation rate detection signals, use them to monitor the average reactor power, and transmit them to the rod block monitors. The rod block monitors select optimal values from average reactor power values and core flow rate signals to perform a monitoring operation.

Abstract: A nuclear reactor includes a propagation space for core melt. The propagation space has a coolant conduit leading to a coolant reservoir and a device which opens in a temperature-dependent manner. The coolant conduit in the propagation space is a spray conduit having a spraying area which covers the cross-section of the propagation space over a large area. The device is controlled in such a way that it opens when the core melt enters the propagation space. Spraying gives rise to a crust on the core melt which reduces heat radiation. At the same time, the propagation space fills with a steam atmosphere which drastically reduces the thermal load on building structures.

Abstract: An absorption structure for absorbing neutrons and a method for producing the absorption structure include placing a neutron-absorbing material between a first sheet and a second sheet. The sheets are joined together and a plurality of voids is formed between them for receiving the neutron-absorbing material. At least one of the sheets has struts or bulges forming the plurality of voids and creating a material bond with the second sheet. The introduction of the neutron-absorbing material into the voids with a virtually arbitrary concentration also makes it possible to adjust the absorption capacity of the absorption structure within wide limits.

Abstract: A fuel assembly for a pressurized water reactor having a fuel rod with a high strength cladding tube including an inner tubular layer of a zirconium alloy with alloying components of molybdenum and 3 to 6 weight percent bismuth, the balance zirconium.

Abstract: Featured is a plasma extrusion dynamo and methods related thereto. Also featured are fusion reactors using such dynamos and methods. In the methodology of the present invention, a steady-state stream of conductive plasma is forced by pressure or momentum to flow into a magnetic extrusion nozzle made up of converging magnetic field lines so as to form a closed, steady-state current loop within the plasma. The plasma current loop in turn forms a closed set of poloidal field lines which interact with the plasma current to compress and confine a portion of the plasma in a toroidal volume. Such pressure and confinement establish the conditions for magnetically confining controlled nuclear fusion reactions for power generation. A fusion reactor using the plasma extrusion dynamo methodology includes a source of high pressure or high velocity plasma, one or more converging magnetic extrusion nozzles, and a plasma exhaust area at low pressure.

Abstract: A system for mounting a vehicle axle housing to a vehicle suspension member, such as a main support member, Z-spring or a gooseneck spring, is disclosed. The invention utilizes a bracket welded onto the axle housing so as to eliminate excessive compressive stresses on the axle housing. The suspension member is sandwiched between a top pad and an axle seat. A pair of downwardly extending U-bolts have their bight portions seated on the top pad with their distal ends extending through holes in the axle bracket. Nuts are attached to the U-bolt distal ends to secure the entire assembly together. The system can accommodate a variety of axle seat sizes which in turn allows for a variety of pinion angles to be effected without necessitating the use of a different axle bracket design for each pinion angle.

Abstract: A forged core plate fabricated from a single piece stainless steel forging is described. The plate has a substantially circular shape and penetrations are provided in the core plate to allow passage of control rod blades into the core and direct recirculation flow past the fuel assemblies. The penetrations are formed from machining "5 holes" per penetration. Particularly, each penetration includes a center through hole to allow passage of the control rod blade and control rod blade guide tube. The through hole has a smaller diameter at the plate top surface to provide a tighter fit to the outside diameter of the guide tube to maintain alignment and minimize flow leakage. The through hole is enlarged at the core plate bottom surface to allow clearance in order to improve the installation and removal of the guide tube. Each penetration also include four peripheral blind holes to direct the recirculation flow into the flow holes located on the sides of the guide tube.

Abstract: A neutron delivery system that provides improved capability for tumor control during medical therapy. The system creates a unique neutron beam that has a bimodal or multi-modal energy spectrum. This unique neutron beam can be used for fast-neutron therapy, boron neutron capture therapy (BNCT), or both. The invention includes both an apparatus and a method for accomplishing the purposes of the invention.

Abstract: Apparatus for rectifying the tendency of a fuel assembly (1) to incline from the perpendicular has a top nozzle support (19) and a base assembly (18) for supporting, respectively, a top nozzle (7) and a bottom nozzle (2) of the fuel assembly. Incorporated in the base assembly is an elevating device (78, 79) which is operable to raise the fuel assembly. When raised, a grinding assembly (62) in the base assembly is able to remove material from the lower surfaces of the bottom nozzle so that they lie in a horizontal plane. The elevating device comprises a gimbal mounting arrangement which includes a gimbal (94) movably supported on a gimbal mount (88) by means of cooperating male and female spherically-shaped bearing surfaces. The grinding assembly includes a grinding wheel (66) which is mounted on a rotor (43) arranged for rotation about an axis along which the elevating device raises the fuel assembly so that material can be removed from each of the lower surfaces during one revolution of the rotor.

Abstract: A storage basket, a storage rack and a method are provided for the compact storage of fuel elements and control rods of a nuclear power plant. The storage basket includes a plurality of inserts for receiving a fuel element. The inserts are disposed in such a way as to form a cruciform gap for receiving a control rod. Four fuel elements as well as one control rod of a boiling water nuclear power plant can be intermediately stored in a carrying well of a fuel element storage rack in a particularly compact and combined way by placing inserts in such a manner as to form a storage basket. A checkered configuration of the carrying wells of the fuel element storage rack permits intermediate positions between the carrying wells to also be supplied with one control rod and four fuel elements.

Abstract: Pipe connector assembly for replacing a core spray line in a nuclear reactor without field cutting, measuring, or welding such line. In one embodiment, the pipe connector assembly includes a first coupling member, a second coupling member, and at least one locking element. The first coupling member includes a flange, a pipe engaging portion, a spherical convex seat portion, a bore and a stud bore. The second coupling member includes a flange having a spherical concave seat portion for receiving the convex seat portion of the first coupling member, a pipe engaging portion, a bore, and a stud bore. The locking element includes at least one spherical washer and a crimp mechanism and couples the first coupling member and the second coupling member by extending through the flange stud bores.

Abstract: A fuel rod for a light water reactor comprises a cladding tube which comprises a zirconium alloy having a composition including 0.6 to 2.0% by weight of Nb, 0.5 to 1.5% by weight of Sn, 0.05 to 0.3% by weight of Fe, and the balance being Zr and incidental impurities; uranium oxide fuel pellets packed in the cladding tube; and end plugs closing both ends of the cladding tube. The cladding tube is sealed by TIG welding with the end plugs. Precipitates having grain diameters of 0.01 to 0.5 .mu.m and comprise intermetallic compounds containing Zr, Nb and Fe are present at grain boundaries in the structure of heat affected zones of the cladding tube, the heat affected zone being adjacent to a bead formed by TIG welding.

Abstract: A method and system for thermal-dynamic modeling and performance evaluation of a nuclear Boiling Water Reactor (BWR) core design is presented. A data processing system is used to execute specific program routines that simultaneously simulate the thermal operating characteristics of fuel rods (or plural groups of fuel rods) within the reactor during a transient operational condition. The data processing system is also used for compilation of a transient response histogram that incorporates the effect of inherent "uncertainties" in various parameters of interest. In an initial phase, the method employs a multi-dimensional approach for the simulation of postulated operational events or an anticipated operational occurrence (AOO) which produces a transient condition in the reactor--such as might be caused by single operator error or equipment malfunction.

Abstract: The current invention involves a means for the production and extraction of the isotope molybdenum-99 for medical purposes in a waste free, simple, and economical process. Mo-99 is generated in the uranyl sulphate nuclear fuel of a homogeneous solution nuclear reactor and extracted from the fuel by a solid polymer sorbent with a greater than 90% purity. The sorbent is composed of a composite ether of a maleic anhydride copolymer and .alpha.-benzoin-oxime.

Abstract: The specification describes a container for spent nuclear fuel rods. The basket of the container comprises a plurality of stacked interlocking grid storage assemblies having an "egg crate" structure. The interlocking grid assemblies have radial tab extensions that extend through an intermediate shell and are affixed to an outer casing. The intermediate shell and the outer casing provide double containment, and the radial tab extensions provide heat sinks for transfer of heat from the storage grid assemblies to the exterior of the container.