Abstract: A resistor temperature device (RTD) trip unit is described. The RTD monitors thermal conditions at an industrial process location, such as in a nuclear reactor. Resistance of the RTD varies in accordance with temperature at the monitored process location. An amplifier circuit produces an output signal, corresponding to the variations in RTD resistance, which signal operates a plurality of relay circuits. The relay circuits variously report process conditions such as failure, the obtaining of a preselected level, etc. Additionally, metering provides a continuous analog indication of thermal conditions at the monitored process locations. To correct for non-linearity inherent in the RTD resistance slope, a recursive feedback path is coupled between the RTD amplifier stage and an RTD current source, such that a decreasing resistance slope produces a complementary increase in current supply to the RTD. The result is a linear output signal from the RTD amplifier.

Abstract: An ultrasonic transducer for use in a high temperature environment and method for fabricating the same. A disk-shaped piezoelectric crystal is weakened in at least one surface in accordance with a predetermined line pattern relative to a first direction in that surface. The crystal is bonded to a thin lens material with a coefficient of thermal expansion dissimilar in this first direction. The predetermined line pattern is adapted to relieve stress in this first direction created by unequal rates of expansion or contraction of the crystal and the lens.

Abstract: Transport apparatus is disclosed for moving a stream of objects along a substantially continuous path between a source and a collection station and past a viewing station. A stream of successive, spatially separated objects is moved into end-to-end abutment to form successive stacks of objects. Each stack is spiraled past the viewing station with minimal vibration to expose the complete surface of each object to inspection. Subsequently each stack is rearranged into spatially separated objects which are rapidly sorted by diverting those objects from the continuous path which do not conform to predetermined criteria upon inspection. The transport apparatus achieves high throughput without compromising the accuracy of the inspection process.

Abstract: Method for precipitating and removing soluble metal compounds from solutions of phosphoric acid. The method is useful in the disposal of metal-containing phosphoric acid waste from electrolytic operations, including such acid solutions contaminated with uranium compounds.

Abstract: A method of controlling the bowing action of fuel channels used in nuclear reactor cores is disclosed. Each channel is heat treated and mounted in its control rod module with an orientation dependent on its prior heat treatment. Upon exposure to radiation, the channels will bow in a desired direction away from the control rod.

Abstract: A stopper apparatus for use in blocking the unvalved nozzle of a cooling fluid filled nuclear reactor pressure vessel includes a plug, typically in the shape of a frusto-conical member having inflatable gaskets for sealing against a seat of generally unknown surface characteristics and means for positioning and urging the plug into position to seal the nozzle. The plug is typically positioned by suspension cables whereby the apparatus can be temporarily inserted and removed from the pressure vessel. The urging means is generally a two-way hydraulically driven jack controlled by remotely-actuated hydarulic lines. The apparatus is a tool which permits temporary sealing of a submerged outlet in a reactor vessel to permit maintenance on a fluid recirculation loop.

Abstract: Apparatus for remotely controlled examination of the control rod drive penetration stub tubes in the wall of a nuclear reactor pressure vessel including a rotatable carriage on which is mounted a reciprocable shaft to which is attached an inspection instrument for scanning the stub tubes.

Abstract: An incinerator is disclosed which includes apparatus for removing ash from an incinerating chamber and which comprises hydraulically operated plows that slide along the floor of the chamber to push the ash towards an ash trough. Ash removal efficiency is improved in accordance with the present invention by the hinged suspension of a brush from the plow face. An auxiliary plow is added to the waste material loading device to clear ash from the highest of several stepped floor levels even in the absence of no new load being entered. The auxiliary plow further includes a clevis assembly which pivots the brush away from the incinerator floor during reverse plow travel.

Abstract: An optical inspection system is disclosed which determines surface and other features of objects by illuminating them with a light beam having substantially uniform light intensity in space and time. The light beam is derived from a light source whose light intensity may vary in space and time. The surface features of each object are inspected by detecting light reflected from the object through a lens system which focuses the reflected light on an array of photosensitive elements. The output signals provided by the array may be used to provide a measure indicative of the conformance of the inspected surface to predetermined criteria. The inspection system is further capable of determining other features of the inspected object, such as the height of the object, by illuminating the object with a second light beam derived from a second light surface.

Abstract: An improved method for compression molding typically brittle, particulate ceramic materials comprising uranium dioxide in the manufacture of nuclear fuel products.

Abstract: Sound waves are generated in a sonic cell and propagated through a gas to a sensor which is coupled to a microcomputer. A gas mixture is first directed into a chamber and the attenuation and transit time of sound waves are calculated. Then, a calibrated gas is directed into the chamber, and the attenuation and transit time are again calculated. With these measurements, the microcomputer calculates the concentrations of at least two gaseous constituents such as hydrogen and water vapor, in the gas mixture. The microcomputer acts also as a control for operating valves and heater coils in response to pressure and temperature sensors coupled with the chamber.

Abstract: In a coupling system for a nuclear reactor control rod and control rod drive, said coupling system being selectively uncouplable by an uncoupling rod, a system of passages for exercising a countervailing force on the uncoupling rod to prevent inadvertent uncoupling during scram.

Abstract: A rotary cylinder calcining system for treating tacky materials with a propensity to adhere to the surfaces of handling apparatus. The system comprises a reciprocating means for freeing the cylinder calciner outlet from any blockages caused by adhering material.

Abstract: A liquid level detector, or detector array, for insertion into the pressure vessel of a nuclear reactor, or into any liquid-containing vessel, for that matter. A coaxial cable supports the detector, which includes a sensing element having a positive temperature-coefficient of electrical resistivity. The detector is driven by a constant current source of electricity and the presence of liquid is determined by making a resistance measurement.

Abstract: Elongated members such as nuclear fuel end plugs are provided to a robot by a vibratory feeder. The robot singly inserts the members into a character stamper or marker and then removes them and drops them down a chute to an inspection site. The member is inserted into a character reader and inspected. Unacceptably stamped members are rejected and for each accepted member the stamper is advanced to a next character. Thus, a next member is stamped with the next character, or permutation of characters, the robot already having provided a new member to the stamper.

Abstract: A fine-motion control rod drive for a nuclear reactor, which can be disassembled in sections. The drive includes a spindle defining a sealing surface to prevent spillage after the drive motor is removed. A spline connection with a sliding key arrangement permits the shaft of the drive motor to be separated from the spindle during disassembly. The drive motor is effective for uncoupling the control rod drive piston from the control rod prior to disassembly.

Abstract: A testable time delay apparatus includes means for testing component operation during any stage of system function and means for continuously monitoring and testing component functions. The device is particularly useful in critical process control applications such as in a nuclear reactor control system.

Abstract: A method and apparatus for determining the subcriticality of masses of uranium by directing epithermal neutrons toward said mass, isolating said material from external thermal neutrons, and measuring the ratio of thermal and epithermal neutrons to epithermal neutrons which enables the establishment of a subcriticality value representative of the mass of uranium.

Abstract: A microprocessor controls pressure transducer testing, calibration, and adjustment. A transducer or unit under test (UUT) receives a fluid pressure signal from a test line, and outputs a corresponding electrical signal. A test pressure is output from a fluid pressure module which is connected to the UUT. A human operator is interrogated by the microprocessor based control unit as to (1) identifying details about the desired pressure UUT to be tested, and (2) the anticipated electrical range to be encountered in reply to an applied test pressure. The microprocessor then sequentially generates electrical output signals which are sent to the test lines to generate the test pressure pulses from a fluid pressure supply. The pressure test pulses are delivered to the UUT. As the UUT receives the sequence of pressure test pulses, the microprocessor records the output electrical signals generated by the UUT, and compares them to an internal reference pressure transducer output.

Abstract: A self-contained modular nuclear reactor which can be prefabricated at a factory location, nuclear-certified at the factory, transported to a field location for final assembly and connection to a large-scale electric-power generating facility. The modular reactor includes a prefabricated nuclear heat supply module and a plurality of shell segments which can be assembled about the heat supply module and which provide a form for the pouring and curing of a cementatious biological shield about the heat supply module. The modular reactor includes passive shutdown heat removal systems sufficient to render the reactor safe in an emergency. A large-scale power plant arrangement is disclosed which incorporates a plurality of the modular reactors.