Abstract: A neutron absorbing apparatus which includes two adjacent neutron absorbing plates and a mounting assembly with latching means configured to be easily secured to fuel assemblies while the fuel assemblies remain under water in a fuel storage rack, thereby eliminating the need to remove the fuel assemblies or the fuel storage rack for installation. The two neutron absorbing plates are positioned orthogonally to form a chevron cross section which can be placed about the fuel assemblies by insertion in the existing space between the fuel assemblies and the cell walls of a fuel storage rack. A prescribed orientation of the chevron configured neutron absorbing plate in the cells of the fuel storage rack together with the selected use of a single neutron absorbing plate economically provides sufficient neutron absorption in all radial directions about the fuel assemblies to maintain safe storage conditions in closely packed fuel storage racks.

Abstract: An improved system and method for testing the free fall time of nuclear reactor control rods. The system employs a plurality of sensor coils which are arranged in tandem along the control rod drive rod housing, having a plurality of the sensors energized by a single transformer. During the rod drop test, the transformers' primary windings are shorted.

Abstract: A method and an apparatus for repairing a core plate having a cracked support structure. The method entails the step of providing a vertical compression load path between the core plate and one or more control rod guide tubes. This is accomplished by installing a plurality of load-bearing wedges between the core plate and the step of each guide tube. Each load-bearing wedge is placed between the core plate and the guide tube machined step so that core plate pressure loads are reacted by the weight of the fuel rather than the core plate support structure. The load-bearing wedges can be installed without removing the guide tube or the fuel support casting.

Abstract: A compact source of intense radiation includes: a multi-element, disc-style, explosive magnetic flux compression generator, switching, peaking-stage generator, plasma flow switch, and a dense-plasma-focus type, pulsed neutron source. The main explosive generator receives initial amounts of magnetic flux and energy from a smaller explosive generator. Explosive action drives the conductors of the main generator together, reducing the inductance and thereby increasing both the current and magnetic energy. A switch closes to connect the peaking-stage generator and plasma flow switch in series with the main generator (and in parallel with the ballast inductor). As the current rises in the plasma flow switch, its plasma armature is electromagnetically-accelerated axially along coaxial electrodes, attaining speeds above 60-70 km/s. Meanwhile, explosive action on the peaking-stage generator provides additional magnetic flux compression.

Abstract: A BWR emergency core cooling system suction strainer. The strainer comprises corrugated metal screen material formed of alternating ridges and furrows with flat chordal lands and flat side walls interconnecting the lands; and an elongated frame with arcuate end support portions shaped to accommodate the ridges and furrows. The flat side walls merge slightly toward one another in a substantially radially inwardly direction and diverge slightly away from one another in a substantially radially outwardly direction to permit release of debris from the screen surface while providing increased screening area for a given volume of strainer.

Abstract: A jugfishing apparatus and signaling device for indicating to a jugfisherman that a fish has struck the bait. The signaling device can include an illumination device such as a light bulb, or an audible signal. When a fish strikes the bait, the signaling device is activated and remains so until de-activated by the fisherman. The force necessary to trigger the signaling device can be adjusted along a continuous range for a variety of fishing conditions, to implement different fishing tactics, and to allow the use of any of a number of standard-size buoyant containers.

Abstract: An electrical circuit backfits into different instrumentation and control (I&C) system hardware configurations as a replacement or upgrade. The circuit has a multiple signal path processing circuit including a multi-functional ASIC. A fixedly configured, multiple signal path connector such as a hardwired multi-pin package removably connected with a pin socket in the processing circuit connects the ASIC with the I&C system for coupling inputs to and outputs from the ASIC and for connecting operative signal paths of the ASIC.

Abstract: The alloy has a base composition similar to that of a zirconium alloy of known type used for the manufacture of an element intended for use in the core of a nuclear reactor, such as a cladding tube, a guide tube, or another structural element of a fuel assembly. In addition, the alloy contains sulphur in a proportion by weight of between 8 and 100 ppm and preferably between 8 and 30 ppm.

Abstract: A passive safety system for a nuclear reactor coolant system including a water storage tank, a heat exchanger positioned within the water storage tank and connected to the hot leg, and a core make-up tank having a tank inlet connected to the heat exchanger and a tank outlet connected to a selected location of the nuclear reactor coolant system. Upon the occurrence of an abnormal condition, water flows by natural circulation from the hot leg through the heat exchanger so that heat may be transferred to the water in the water storage tank, and thereafter flows through the core make-up tank and into a selected location of the nuclear reactor coolant system to provide cooling for the reactor core.

Abstract: The subject invention is a nuclear fusion reactor. It operates by colliding particle beams from at least four different directions. The beams collide in a matrix that guides the particles to the reaction's center by their mutual electrostatic repulsion. In the preferred embodiment the reactor comprises primarily four high energy particle accelerators (11a, 11b, 11c, and 11d). At the reactor's center, the accelerators' four beams intersect at angles of approximately 109.471220634491 degrees. The exact measure of the preferred angle is given by the measure of the obtuse interior angle of an isosceles triangle that has two sides measuring the square root of three units and a base measuring twice the square root of two units. Accelerated to fusion producing velocities, the four particle beams intersect in a high-vacuum reaction chamber (12). The resulting collision matrix funnels the accelerated particles into the center of the reaction zone causing some of the fuel particles to fuse rather than to scatter.

Abstract: A method and apparatus for converting radioactive energy into electrical energy is provided and includes a first radioisotope (24) emitting alpha particles and a second radioisotope (28) emitting beta particles. A first plate (16) is positioned proximate the first radioisotope (24) and is adapted for capturing the alpha particles wherein the first plate (16) is positively charged. A second plate (18) is positioned proximate the second radioisotope (28) and is insulated from the first plate (16). The second plate (18) is adapted for capturing the beta particles wherein the second plate (18) is negatively charged for establishing an electrical potential between the first plate (16) and the second plate (18). A housing accommodates the radioisotopes (24,28) and plates (16,18) and has a first contact (40) connected to the first plate (16) and a second contact (42) connected to the second plate (18). An electrical potential is generated between the two contacts (40,42).

Abstract: An extraction tool for removing a partial length fuel rod from a fuel bundle assembly, wherein the partial length fuel rod has an upper end plug, the tool comprising an extension rod having a pair of gripper jaws mounted at one end thereof, the gripper jaws shaped and sized to engage the upper end plug; and a locking tube slidably received over the extension rod and engageable with the gripper jaws to lock the gripper jaws to the upper end plug.

Abstract: In order to use up a stockpile of weapons-grade plutonium, the plutonium is converted into a mixed oxide (MOX) fuel form wherein it can be disposed in a plurality of different fuel assembly types. Depending on the equilibrium cycle that is required, a predetermined number of one or more of the fuel assembly types are selected and arranged in the core of the reactor in accordance with a selected loading schedule. Each of the fuel assemblies is designed to produce different combustion characteristics whereby the appropriate selection and disposition in the core enables the resulting equilibrium cycle to closely resemble that which is produced using urania fuel. The arrangement of the MOX rods and burnable absorber rods within each of the fuel assemblies, in combination with a selective control of the amount of plutonium which is contained in each of the MOX rods, is used to tailor the combustion characteristics of the assembly.

Abstract: A system for controlling control rods which can be moved into and out of a reactor core of a nuclear power plant, includes a selector device, a monitor device and a rod control device. The selector device contains travel sequences which are selectable and defined for regulating the nuclear power plant, i.e. allocation and movement sequences of the control rods, and it transmits the selector signals allocated to each travel sequence to the rod control device. The monitor device checks the selector signals for acceptability while taking into account the structural features of the reactor core and the control rods, which are allocated to the respective travel sequence, in particular proximity relationships of the control rods. If the selector signals are acceptable, an enable signal is transmitted to the rod control device and the rod control device induces a displacement of the control rods according to the selector signals.

Abstract: A fishing leader straightening device comprising compression spring loaded rods to hold the hook attached to one end of a shock tippet and slots to receive the knotted ends of the shock tippet to enable the shock tippet to be straightened. The base member may be provided with suction cups so that it may be held on the deck of a fishing boat.

Abstract: In a nuclear reactor including a reactor vessel and a core shroud disposed within the reactor vessel in laterally spaced relation, a seismic support includes a spacer extending between laterally opposed surfaces of the reactor vessel and the core shroud to limit lateral movement of the core shroud relative to the reactor vessel and a deformable member carried by the spacer and having a configuration to deform substantially elastically in response to impacts caused by an operating basis earthquake and substantially plastically at relatively constant load in response to impacts caused by a design basis earthquake. The deformable member can be carried at an end of the spacer adjacent the reactor vessel or between the spacer and a bearing plate, and can be formed of a material having a yield strength less than that of the spacer and/or be of reduced cross-sectional area as compared with the spacer to yield under a desired seismic load.

Abstract: A strainer for filtering a pumped fluid has a strainer body having a wall provided with fluid inlet perforations in an outer surface, a surface cleaning scraper or brush in juxtaposition with the outer surface, and a drive operatively connected to the surface cleaner for moving the surface cleaner over the outer surface for removing accumulated debris. At least one nozzle is oriented towards the cleaned outer surface of the strainer body for directing a jet of liquid against the perforations to assure that the perforations are clear. The strainer is thus self-cleaned continuously without requiring a back wash operation, allowing continuous flow through the strainer.

Abstract: A device for collecting reactor-meltdown products from a reactor pressure vessel includes an antechamber disposed below the reactor pressure vessel, an expansion chamber having a floor forming an expansion surface for reactor-meltdown products, and a bulkhead being disposed between the antechamber and the expansion chamber and being destructible by the reactor-meltdown products. The bulkhead has a plurality of parts including at least one part being thermally destructible by the reactor-meltdown products. The at least one part is joined to the other parts for clearing a flow path for the reactor-meltdown products from the antechamber into the expansion chamber upon a destruction of the at least one part.

Abstract: The present invention relates to an operator work station for nuclear power plants which can provide plant information in an effective way during abnormal/emergency conditions so that the operator can take necessary actions to recover the nuclear power plants. The operator work station for nuclear power plants of the present invention comprises dynamic alarm console; system information console; computerized operating procedure console; system-alarm connecting system which connects the alarm console with the system information console; and, system-procedure connecting system which connects the system information console with the computerized operating procedure console. According to the operator work station, efforts and time required for the operator to judge for himself, and possibility of mistakes of judgement are properly excused, since the operator can easily recognize the system where abnormality occurs, based on the generated alarms.

Abstract: A bimodal propulsion and power nuclear reactor with coaxial power and propulsion cores, each with its own primary propellant/coolant. An inner core region provides electrical power while an outer annular core region surrounding the inner core region has, passageways for heating a gaseous propellant.