Abstract: Processes for constructing complex turbine structures by the assembly of less complex sub-structures. The component sub-structures are bonded together at opposed mating surfaces by transient liquid bond phase techniques. The sub-structure mating surfaces are machined prior to application of the bonding material to remove oxide from the mating surfaces and ensure dimensional tolerances. Bonding material is applied to the mating surfaces by sputter deposition. Masks can be applied to the mating surfaces prior to application of the bond material so as to selectively apply bond material at only predetermined locations on the mating surface, thus eliminating excessive use of bond material for bonding the component sub-structures.

Abstract: A welding process of repairing a ferrous NiMoV low alloy steel turbine component. A first and a second layer of weld material are welded to the turbine component at electrical current levels chosen so as to prevent a substantial decrease and a substantial increase in the hardness of the component. This method involves selecting these electrical current levels. Additionally, this invention relates to selecting appropriate electrical current levels that minimizes the difference between a maximum and a minimum level of hardness while welding a first and a second layer of weld material. This invention also includes a method for preventing a substantial decrease in the hardness of the component as a result of the welding process.

Abstract: A gas turbine that has turbine vanes that can be cooled with either steam or air includes a compressor that compresses air, a combustor enclosed within a shell and in flow communication with the compressor, a turbine in flow communication with the combustor and receiving hot gas from the combustor and turbine vanes. The turbine vanes having an airfoil, a shroud and a cooling circuit that cools the airfoil and the shrouds with either steam or air.

Abstract: A system is disclosed that provides for a more efficient combined cycle turbine system by using heated coolant returning from the gas turbine engine to pre-heat fuel before that fuel is injected into the combustor. Coolant, such as steam, that is used to cool gas turbine combustors and/or transitions carries high grade heat energy that was removed from the top cycle. By returning the heat energy to the incoming fuel, energy is recovered at a more efficient rate than would result from recovering that heat energy in the bottom cycle.

Abstract: A cooling manifold assembly for cooling combustion turbine components is provided. The manifold assembly comprises at least a first and second connector box. Each one of the first and second two connector boxes comprises a housing. A fluid supply conduit and return conduit are securely coupled with the housing. The fluid supply conduit is adapted to be in fluid communication with a cooling fluid for cooling a hot turbine part. The return conduit is adapted to be in fluid communication with a cooling fluid that has extracted heat from a turbine hot part. A cooling fluid supply pipe for supplying a cooling fluid to the first and second connector boxes is provided. The supply pipe comprises a side wall that defines a coolant flow channel with a first opening at a first end, and a second opening at a second end. The first end of the fluid supply pipe is mechanically coupled in fluid communication with the fluid supply conduit of the first connector box.

Abstract: An apparatus for cooling the trailing edge portion of a gas turbine vane. Two radially extending passages connected to the outer shroud direct cooling fluid to a plenum formed about mid-span adjacent the trailing edge. Two arrays of cooling fluid passages extend from the plenum. One array extends radially outward toward the outer shroud while the other array extends radially inward toward the inner shroud. The plenum distributes the cooling fluid to the two arrays of passages so that it flows radially inward and outward to manifolds formed in the inner and outer shrouds. The manifolds direct the spent cooling fluid to a discharge passage.

Abstract: A method of removing blades from the rotor of a turbo machine, such as a steam or gas turbine, in which material deposits formed between the surfaces of the blade root and its retaining groove have effectively bonded the blade root to the rotor groove. The blade root and groove are submersed in a liquid medium enclosed in a tank. Transducers installed on the tank radiate ultrasonic pressure waves into the liquid medium that breakup the material deposits through cavitation, thereby loosing the bond between the blade root and the groove. The blade is then removed from the tank and the blade slid out of the groove.

Abstract: A passive blade vibration monitor sensor for determining an arrival time of a blade of a combustion turbine during operation, the sensor includes an optical lens which receives infrared radiation generated by the blade of the turbine and generates a sensor signal from the received infrared radiation, the sensor signal indicating an arrival time of the blade of the combustion turbine. Target material having an emissivity lower than the emissivity of the blade may be placed on the blade to enhance sensor sensitivity especially in shrouded blade environments.

Abstract: A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn.

Abstract: A low pressure steam turbine and generator low alloy steel disc rotors with extended useful life properties. A ring member of the disc rotor has disposed on it multiple weld layers of ferrous material, forming a weld region. The ring member is made of a low alloy ferrous metal alloy having less than about six weight percent alloying ingredients including chromium. The chromium content of the weld region increases overall from a portion of the weld region adjacent to the ring member to a portion of the weld region farthest from the ring member. This general increase is accomplished using weld metal of a single chromium concentration of between 9% and 17% chromium and varying the welding parameters.

Abstract: A laser welding apparatus and method are used to weld the inner surface of small diameter tubes such as nuclear heat exchanger tubes. A weld filler metal carried by a rotatable laser weld head is fed into the weld zone to produce deeply penetrating weldments of low profile. The apparatus and method can effectively be used to repair cracks in heat exchanger tubes to thereby provide extended service life.

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: An automated system for determining positions of a plurality of nuclear fuel assemblies organized in an array within a housing of a nuclear power plant includes a radiation hardened, underwater camera for inputting images of the nuclear fuel assemblies with respect to each other or with respect to a baffle wall of a nuclear reactor core, a digital signal processor for generating a second digitized image including a plurality of pixel elements of the nuclear fuel assemblies from the first image, and a workstation for determining the positions of the nuclear fuel assemblies with respect to the baffle wall from counts of the pixel elements.

Abstract: Disclosed is apparatus and a system for measuring and monitoring the actual mechanical power being produced by an electric motor and measuring and monitoring the reactive torque acting on and the rotational speed of a drive shaft of the electric motor used to drive a valve actuator of a motor operated valve (MOV). The apparatus and system is comprised of a motor power measuring cell inserted between and bolted to the electric motor housing and to the valve actuator housing of commercial MOVs to provide continuous in-service valve and motor diagnostics. The motor power measuring cell is provided with a first measuring means for measuring the torque acting on the drive shaft and a second measuring means for measuring the rotational speed of the drive shaft.

Abstract: Disclosed is a diagnostic system for measuring and monitoring selected operating parameters of a solenoid operated valve. The valve assembly, comprised of a valve body, a valve plug attached to a valve stem is actuated or operated by a solenoid. The valve assembly is provided with one or more sensors attached to or positioned adjacent to the valve assembly to measure and monitor selected operating parameters of the valve assembly and provide electrical output signals indicative of the measurements to a signal conditioning, processing and data collection apparatus used to receive and record the electrical output signals. The diagnostic system allows the user of the valve to measure and monitor the various electrical and mechanical activities of the valve during its operation while in service and to see if the valve is operating within its design parameters.

Abstract: Electromagnetic field pulses are induced in an electrically conductive/magnetically permeable housing and valving element movable within the housing of a check valve by an energizing coil placed against the housing and forming a loop extending substantially over the full range of travel of the valving element. At least two sensing coils positioned within the loop of the energizing coil proximate the two ends of the range of travel of the valving element, and preferably an array including additional sensing coils spaced between the two end coils, detect transient responses to the induced pulses from which the position of the valving element is determined.

Abstract: A motor operated valve monitoring system utilizes two diagnostic couplings with quick disconnect electrical connectors. One coupling is used for monitoring switch actuation on the motor operated valve, and the second is for measuring three phase power to an AC motor on the valve. These couplings are connected in-line with the quick disconnect connectors and allows the user to perform a test without having to remove the limit switch cover from the actuator. These couplings will reduce testing time for conventional valve monitoring systems, and provide for readily mountable sensors for installation of an online valve diagnostic system to an existing valve and valve operator.

Abstract: A fastener for fastening together a plurality of members, such as the plurality of members comprising a tube plug, and a method for plugging an opening in a solid member, which may be a tube, for preventing the flow of fluid through the opening in a solid member or through the tube, such as a nuclear steam generator tube, comprises a first member, such as a shell, a second member, such as a bolt, and locking structure. A deformable tab portion of the locking structure may have an undercut positioned so that when the second member is installed within the first member, a first surface of the undercut is bent toward a second surface of the undercut thereby plastically deforming the tab portion into a recess in at least one of the first and the second members for automatically securing together the plurality of members.

Abstract: A two-way communication system is provided having a stationary device and a portable passive device. The portable passive device has circuitry for storing and transmitting coded information. The stationary member transmits a signal at a first frequency via magnetic field and the portable passive device transmits coded information stored on circuitry provided therein at a second frequency also via a magnetic field. An antenna circuit is provided in the portable passive device having a parallel resonant circuit and a series resonant circuit. The parallel resonant circuit derives operating power from the signal at a first frequency for use in the circuitry provided in the portable passive device. The series resonant circuit transmits coded information at a second frequency.

Abstract: A semiconductor device has material removed from the back of the substrate and a manufacturing process is provided for manufacturing these devices. In the exemplary embodiment, a GaAs FET chip is formed by a process including the step of etching the GaAs substrate from the back of the chip in a defined removal region to reduce the dielectric constant in the region of the source-to-drain path. A buffer layer of differing material provided between the active layers and the substrate prevents etching of the active layers during the removal process. To allow simplified etching patterns, the source-to-drain path may be laid out on the surface of the chip in a variety of patterns, including "packed" patterns concentrating a large path area in a small surface area of the chip. Optionally, this buffer layer may also be etched away in a further processing step.