Abstract: A pressurized water reactor (PWR) is protected from departure from nucleate boiling and from hot leg boiling by generating a segmented delta temperature trip function having a first line segment which closely follows the departure from nucleate boiling core limit line and a second segment closely following the hot leg boiling core limit line. Each line segment is a function of the average core temperature and coolant pressure with the departure from nucleate boiling segment further adjusted for axial power distribution. The two set points are continuously compared to actual delta temperature in four independent channels. If either set point is exceeded in at least two channels, the reactor is tripped.

Abstract: A pump powered by a canned motor has a removable stator cartridge. One end of a generally hollow pressure housing is secured to a pump housing. An annular stator cartridge is removably secured in the pressure housing. An annular gap between the inner surface of the pressure housing and the outer surface of the stator cartridge defines a flow path for cooling fluid to permit the stator cartridge to be surrounded by cooling fluid. A rotor is operatively positioned inside the stator cartridge to form an electric motor when the stator cartridge is energized. The output shaft of the rotor is connected to an impeller in the pump housing. The rotor is rotatably supported by bearings. An end cap is removably secured to the other end of the pressure housing. Removal of the end cap permits access to and removal of the stator cartridge without requiting removal of the motor from the pump housing.

Abstract: A low NOx generating combustor in which a first lean mixture of fuel and air is pre-heated by transferring heat from hot gas discharging from the combustor. The preheated first fuel/air mixture is then catalyzed in a catalytic reactor and then combusted so as to produce a hot gas having a temperature in excess of the ignition temperature of the fuel. Second and third lean mixtures of fuel and air are then sequentially introduced into the hot gas, thereby raising their temperatures above the ignition temperature and causing homogeneous combustion of the second and third fuel air mixtures. This homogeneous combustion is enhanced by the presence of the free radicals created during the catalyzation of the first fuel/air mixture. In addition, the catalytic reactor acts as a pilot that imparts stability to the combustion of the lean second and third fuel/air mixtures.

Abstract: A stationary vane assembly for a turbo-machine in which the vane is restrained against motion in the circumferential direction by first and second locking pins. The second locking pin extends radially through a turbine cylinder and engages a notch in a downstream support rail formed on the vane outer shroud. The first locking pin is affixed to the front radial flange of the cylinder and has a projection that extends into a notch in an upstream support rail formed on the outer shroud. An over-sized slot in the first locking pin allows the circumferential location at which the first locking pin is fixed to the cylinder to be adjusted, thereby ensuring that the first locking pin can be pre-loaded against the outer shroud notch at assembly in a manner that will allow it to restrain the motion of the vane.

Abstract: A method and system for improved continuous ion exchange chromatographic elemental separations of zirconium and hafnium and also for isotopic separations thereof from crude zirconium minerals by using zirconium (also containing hafnium) sulfate feedstock solutions, sulfate eluant solutions, anionic exchange resins, and reduced ion exchange column operating temperatures. The method and system of the invention provides sulfate feedstock solutions by completely converting the carbochlorination products of zircon sand to sulfate solutions prior to feeding to the ion exchange chromatographic column. The method and system of the invention is performed in a continuously operating continuous annular chromatograph (CAC). Nuclear grade substantially purified zirconium and hafnium metals are produced.

Abstract: An information system for a complex plant which clearly presents to the operator, in parallel as alarms, abnormal process changes which the operator can, at his discretion, manually respond to either to prevent conditions from deteriorating further to the point where automatic protective actuations will be initiated or where automatic protective actuations have not been completed because of a malfunction or were completed but have not been successful. Such alarms are displayed on a dedicated alarm display panel which spatially groups components and subsystems to show appropriate relationships, with the alarm messages shown in the associated area of the display so that possible disturbance propagation can be foreseen. Messages related to uncompleted automatic protective actuations may include a list of faults which prevented completion of those actuations.

Abstract: An apparatus for use with a search device and a foreign object extrication device in a steam generator includes a router having two conduits for routing the search and extrication devices, and a positioning mechanism for positioning the conduits. The extrication device may include a cable having a pushing mechanism for pushing a foreign object within the steam generator and a hook mechanism for pulling the foreign object. Alternatively, the extrication device may include a loop mechanism for pulling. The extrication device may include a cable having a slotted end for pushing. Alternatively, the cable may have an anvil for pushing. The router may include a guide tube interconnected with the first conduit for guiding the search device from the tube lane into a selected one of the tube rows of the steam generator and another guide tube interconnected with the second conduit for guiding the extrication device from the tube lane into the selected tube row.

Abstract: A passively temperature actuated valve has a shape memory alloy (SMA) mechanism connected to a lever arm which engages the valve stem to actuate the valve against the biasing force of a valve stem biasing spring when the ambient temperature rises above the transition temperature of the SMA. The SMA mechanism can include an SMA rod, but preferably has a tube of shape memory alloy supported in couplings which allow ambient fluid to freely pass through the tube. A stack of Bellville springs concentrically mounted over the tube biases the tribe to the elongated condition when below the transition temperature. An optional latch latches the valve in the actuated position if it is required that the valve remain actuated when the ambient temperature falls below the transition temperature and the Bellville springs again elongate the SMA member.

Abstract: A color printing system including thin film electroluminescent (TFEL) edge emitter devices and an electronic interface for driving the TFEL devices. The TFEL edge emitter devices form a multi-color TFEL edge emitter structure operable for emitting a plurality of different colors of light onto a media. The electronic interface receives gray scale data for pixels and converts it into a serial data stream used to drive pixels in the TFEL edge emitter structure. The electronic interface further includes a compensation memory for compensating for pixel variations in the TFEL structure. The compensation memory can be periodically recalibrated "in place" during the life of the printing apparatus.

Abstract: An apparatus for positioning a search device and a retrieval device in a steam generator includes a guide mechanism for guiding the devices through the annulus to the tube sheet and drive mechanisms for driving the cables of the devices. Alternatively, a plurality of guide mechanisms and a plurality of drive mechanisms may be provided for a plurality of search and retrieval devices. The guide mechanism may include two double-dog-leg, single-piece, guide tubes between the handhole and the tube sheet for guiding the cables. The drive mechanisms may each include a pair of pinch rollers for driving a corresponding cable, a remote energizing mechanism for independently energizing the corresponding drive mechanism, and a reversible motor having a drive shaft. One pinch roller is driven by one drive shaft and the other pinch roller freely rotates about the other drive shaft. The guide mechanism may also include a guide plate mounted to the handhole and dual sets of guide tubes for the two halves of the tube sheet.

Abstract: A passive nuclear power plant includes a reactor vessel enclosed by a containment shell. An in-containment cooling system piped with an out-of-containment heat sink, includes an in-containment heat exchanger vertically extending adjacent the sidewall of the containment shell for inducing natural circulation of the air in the containment shell. The heat exchanger has substantially parallel water-conducting pipes with cooling fins vertically extending therefrom for transferring heat from the naturally circulating air and for condensing steam from the atmosphere.

Abstract: Apparatus and method for remotely positioning a probe, such as an examination or repair probe, in a tubular member. The tubular member may be a nuclear steam generator heat transfer tube to be examined or repaired by the probe. The probe is connected to a conduit which supports the probe as the probe advances along the inner diameter of the tube to the location of the tube requiring examination or repair. The conduit has a portion thereof wound about a take-up reel. As the probe and conduit advance in the tube, it unwinds from about the take-up reel. However, as the conduit unwinds from about the take-up reel, it may tend to develop a "kinked", twisted or contorted region therein inducing torsional stress in the conduit. Such torsional stress may be severe enough to break the conduit. The apparatus of the invention includes a gripper capable of gripping the conduit and also includes a rotator connected to the gripper for rotating both the gripper and the conduit gripped thereby.

Abstract: Apparatus for providing reactive compensation and positive real power compensation in an ac electric power transmission system, utilizes a solid state inverter to inject a series compensation voltage into the transmission line at a controllable magnitude and a controllable phase angle between + or -90 electrical degrees relative to transmission line current. The positive real power needed by the inverter is drawn from the transmission line by a rectifier shunt connected to the line.

Abstract: A replacement rod for insertion into a nuclear fuel assembly to replace a fuel rod containing a neutron absorbing, fissile fuel, includes Hafnium sufficient to substantially replace the neutron absorption capacity of the fuel rod. The replacement rod also includes a non-fissile second material that is commonly used for structures in nuclear fuel assemblies. The second material is preferably selected from the group consisting of a stainless steel, a zirconium alloy and zirconium. In one embodiment, the Hafnium is fabricated into a cylindrically-shaped rodlet, or core, and the second material is fabricated into an annulus around the core. Alternatively, the Hafnium and the second material are each distributed about uniformly throughout a cylindrical volume of the replacement rod. Refurbishing nuclear fuel assemblies by replacing damaged fuel rods with replacement rods according to the invention obtains an improved peaking factor over prior art methods.

Abstract: A gas turbine vane having an inner shroud that is cooled by a portion of the cooling air directed to a cavity between two adjacent rows of discs. A portion of the cooling air in the cavity flows through impingement plates and impinges on the inner surface of the inner shroud. Another portion of the cooling air flows through a passage in the leading edge of the inner shroud that has a pin fin array for enhanced cooling. The impingement plates form chambers that collect both the impingement air and the pin fin passage air and direct it through holes in the trailing edge of the inner shroud for cooling of the trailing edge. Longitudinal passages along the side of the inner shroud direct the cooling air from the pin fin passage tot the trailing edge.

Abstract: In a nuclear reactor water cleanup pump, a purge fluid is continuously delivered during at least the operation of the pump into the cavities containing the bearings and the electrical motor at a desired flow rate. The desired flow rate being based on the heat loss from said pump and a differential temperature defined as being the difference between the predetermined temperature of the purge fluid delivered into the pump and the desired temperature for the purge fluid exiting the pump.

Abstract: An improved method for cleaning heat exchangers, wherein a first cleaning liquid is used to remove a majority of the accumulated sludge and deposits from the surfaces of the heat exchanger, and a second cleaning liquid is used to remove deposits from the crevice regions of the heat exchanger. Boiling may be induced in the crevices between the tubes and the tube support plates by venting of the secondary side while heating through the primary side of the heat exchanger. Repeated venting as the water level is lowered results in crevice boiling at each tube support plate. Mechanical cleaning techniques such as pressure pulse cleaning may be utilized with either or both of the cleaning liquids. Additional liquids may be introduced into the heat exchanger to provide further cleaning action or to facilitate flushing of the previous cleaning liquids.

Abstract: The girth welds joining the end plugs and the hollow tubes of nuclear fuel rods are inspected automatically using a technique that averages reflectance values, compares the reflectance values to standards defined as proportions of the average, and counts adjacent pixels outside the standards to analyze for defects exceeding a minimum defect size. The minimum defect size is checked by counting the adjacent pixels in mutually perpendicular directions, such as rows and columns in the collected matrix of pixel data. The maximum count in the two directions can be different, for profiling the maximum acceptable defect as to the direction of its extension relative to the tube and/or weld. Tubes are inspected prior to surface treatments that may conceal defects.

Abstract: An apparatus for and a method of continuously supplying a conditioned fuel, such as CO and H.sub.2, to an electrochemical generator such as a high temperature solid oxide electrolyte, fuel cell generator (SOFC), for electrochemical reactions and continually regenerating a hydrocarbon reformation catalyst by providing at least two iron metal/iron oxide beds. At least one bed, a reformation bed, is mainly in the iron oxide (FeO) condition and incoming hydrocarbon feed fuel gas, such as natural gas, will be reformed or conditioned at a temperature of about 600.degree. C. to 800.degree. C. on the iron oxide to CO and H.sub.2 which represents the fuel to be fed to the fuel cells of the electrochemical generator, thereby reducing iron oxide to iron metal (Fe). While the FeO reformer bed is being reduced to Fe, the at least one other bed, an oxidation bed, which previously served as a reformer bed mainly in the iron metal condition (Fe) is oxidized at a temperature of about 600.degree. C. to 800.degree. C.

Abstract: A transport refrigeration system for heating and cooling a conditioned space is provided that includes an improved, combined heat exchanger and economizer for increasing the efficiency of the refrigeration cycle. The system includes a refrigerant compressor driven by an internal combustion engine that includes suction and discharge ports, and an intermediate pressure port; a refrigeration circuit including a heating coil and evaporator assembly thermally connected to the conditioned space, and a mode valve for selectively routing the refrigerant through either the heating coil or the evaporator assembly via a condenser to heat or cool the conditioned space, respectively. The combined heat exchanger and economizer includes a tube connected to the intermediate suction port of the compressor, a shell for conducting refrigerant to the evaporator assembly depending upon the position of the mode valve, and a jacket for circulating engine coolant.