Abstract: The invention projects a known geometry light source onto the surface of an object. A camera with a known distance and angular orientation with respect to the light source is used to capture the light source image on the object. The normal to the surface of the object is determined from the known size of the projected image, the angles of the intersecting lines in the projected image and the corresponding values in the received image. If a hole is to be located, the image projected is a cross and the center of the hole is determined by finding the end points of image line segments which correspond to hole edges. The center and surface normal define the location and orientation of the hole. The surface normal and the center of the hole are transformed into a robot coordinate system and a robot can be commanded to insert a bolt into the hole based on the values.

Abstract: An elongated nuclear fuel cladding tube is provided with at least two annular concentric layers which are bonded to each other. The inner layer is composed of a zirconium base alloy. The outer layer is composed of a titanium base material exhibiting excellent corrosion resistance in elevated temperature and pressure aqueous environments.

Abstract: Seamless tubing is formed from welded precursors of zirconium or titanium material by heating successive axial segments of welded tubing completely through the wall of the tubing to convert the material to the beta phase and then rapidly quenching the segments, with the heating and quenching effected so as to prevent the growth of beta grains within the material.

Abstract: A debris trap is mounted within a bottom nozzle of a fuel assembly so as to capture and retain debris carried by coolant flowing from the lower core plate openings of the nuclear reactor to the fuel assembly. The trap includes a structure disposed below the adapter plate of the bottom nozzle and between the corner legs of the nozzle. The structure is composed of a plurality of straps aligned with one another in a crisscross arrangement and defining a plurality of interconnected wall portions which form a multiplicity of small cells each having open opposite ends and a central channel for coolant flow through the trap. A plurality of spring-like fingers are punched out of the wall portions and bent to extend into the cell channels toward the downstream end of the trap structure to provide means to capture and retain pieces of debris carried through the channels by flowing coolant.

Abstract: A system for effecting transport over a surface among a plurality of terminals, including at least one transport vehicle movable over the surface, light barriers dividing the surface into a plurality of contiguous elemental zones and sensing the passage of a vehicle across a boundary between two contiguous zones, light signal generators for emitting light signals identifying each zone occupied by a vehicle and identifying the location of each terminal, logic circuitry connected between the barriers and said light signal generators for controlling the light signals identifying each zone in response to passage of a vehicle across a boundary, a photoelectric receiver carried by the vehicle for sensing light signals produced by the light signal generators and producing electrical signals representative of the light signals, and a vehicle movement control circuit carried by the vehicle and connected to receive the electrical signals from the photoelectric receiver for controlling the movement of the vehicle in dep

Abstract: An installation composed of a plurality of machines disposed adjacent a common work space delimited by a boundary surface, each machine being associated with a respective portion of the boundary surface and having a work-performing member movable into and out of the work space through the associated boundary surface portion, and an optical monitoring system composed of a plurality of optical monitoring assemblies each associated with a respective machine.

Abstract: The fissile inventory required in operating a negative power coefficient nuclear reactor in an electric power generating system is reduced by cycling the load imposed on the system when 100% power can no longer be maintained at equilibrium due to xenon poisoning in order to induce an oscillation in the xenon concentration which is in antiphase wtih the power requirements so that 100% power can be maintained at least during part of the day. The load can be progressively reduced by a preset amount each night or a xenon suppression controller which forecasts the xenon reactivity at the time selected for a return to full power as a function reactor history, current reactor flux and an arbitrary load schedule can be used to determine the maximum reduced power level that will permit operation at full power at the selected time.

Abstract: A nuclear fuel assembly includes and upper yoke, a base, an elongated, outer flow channel disposed substantially along the entire length of the fuel assembly and an elongated, internal, central water cross, formed by four, elongated metal angles, that divides the nuclear fuel assembly into four, separate, elongated fuel sections and that provides a centrally disposed path for the flow of subcooled neutron moderator along the length of the fuel assembly. A separate fuel bundle is located in each of the four fuel sections and includes an upper tie plate, a lower tie plate and a plurality of elongated fuel rods disposed therebetween. Preferably, each upper tie plate is formed from a plurality of interconnected thin metal bars and includes an elongated, axially extending pin that is received by the upper yoke of the fuel assembly for restraining lateral motion of the fuel bundle while permitting axial movement of the fuel bundle with respect to the outer flow channel.

Abstract: Apparatus for monitoring the processes of a nuclear reactor to detect off-normal operation of any process and for testing the monitoring apparatus. The processes are evaluated by response to their paramters, such as temperature, pressure, etc. The apparatus includes a pair of monitoring paths or signal-processing units. Each unit includes facilities for receiving on a time-sharing basis, a status binary word made up of digits each indicating the status of a process, whether normal or off-normal, and test-signal binary words simulating the status binary words. The status words and test words are processed in succession during successive cycles. During each cycle, the two units receive the same status word and the same test word. The test words simulate the status words both when they indicate normal operation and when they indicate off-normal operation. Each signal-processing unit includes a pair of memories.

Abstract: Modular bundles of U-shaped tubes having primary fluid conduits with compression seals which cooperate with a pair of transversely disposed parallel support plates to allow removal and replacement of the modular tube bundles to facilitate maintenance and extend steam generator life in pressurized water reactors.

Abstract: A reactor core having tandem arranged fuel regions for use in a water moderated nuclear reactor. An upper core region is fueled with enriched uranium oxide; while, a lower core region is fueled with a plutonium oxide. An intermediate core region contains natural uranium oxide.