Abstract: In a steam turbine, a device for keying hubs of adjacent wheels together, wherein the wheels are not an integral part of the shaft of a rotor of the steam turbine and may be secured to the shaft by an interference shrink-fit at the surface of a bore through the hub of the wheel, comprises a substantially I-beam shaped key disposed in a keyway formed between adjacent hubs. A lip extends axially from the outer periphery of a pair of opposing end faces of adjacent hubs, the outboard surface of one lip of the pair of opposing end faces being in close proximity to the outboard lip of the other lip of the pair of opposing end faces. A respective pair of lands on each respective pair of opposing end faces defines a substantially radial slot respectively between the pair of lands. Streamlined fillets respectively transition the leading and trailing faces of each respective member of the pair of lands to the respective opposing end face.

Abstract: A stator core for a dynamoelectric machine includes two pairs of dovetail slots disposed at respective predetermined radial positions in each armature slot. All stator slots contain armature bars. A few equally spaced stator slots also contain "P" bars atop or radially inward from armature bars. Wedges are installed in the radially outer dovetail slots of stator slots containing only armature bars. Wedges are installed in radially inner dovetail slots in stator slots containing both armature bars and "P" bars.

Abstract: A two-stage hydraulic solenoid valve for controlling the application or release of hydraulic pressure to components of a steam turbine control system. The valve includes a primary hydraulic circuit in which a floating poppet operates between first and second valving positions to connect the valve's outlet port to either an inlet port or a drain port so that the connected control system components receive full hydraulic pressure or are provided with a pressure release path. A secondary hydraulic circuit controls the poppet position through a solenoid actuatable ball and valve seating arrangement wherein a ball is alternatively positioned between a pair of valve seats to switch fluid connections to poppet actuation chambers, one such chamber being located at each end of the poppet. The ball is positioned in sealing contact with one valve seat by the solenoid and is returned to the other seat by fluid pressure upon deactivating the solenoid.

Abstract: An adjustable gain controller for a steam turbine valve position control loop includes an electronic operator, a proportional controller, a derivative controller and an integral controller. A steam flow condition error signal is amplified by the reciprocal of the valve's regulation value. The amplified error signal is supplied to the electronic operator and to the integral controller. The electronic operator includes means for initially selecting a value of A and n and generating a gain factor from a nonlinear gain characteristic function utilizing those values in combination with the valve's regulation value and the normalized error signal. The electronic operator multiplies the amplified error signal by the gain factor and applies the resultant signal to the proportional controller and the derivative controller. The output signals from the proportional, derivative and integral controllers are summed together and that sum is input into an electrohydraulic valve actuator system.

Abstract: The velocity and change in velocity of a rotating or otherwise moving surface is measured by a laser Doppler technique. In particular, a diffraction grating is formed on the moving surface either by machining processes or by affixing a ready-made grating thereto. The grating surface exhibits periodicity in one or more directions, either separately or simultaneously. The presence of the grating produces Bragg order diffraction reflections at specific angles relative to the surface. These Bragg order reflections contain information, in the form of Doppler shifts, concerning the motion of the surface and the body to which it is attached. This Bragg order Doppler shift information is readily analyzable using conventional signal processing apparatus and processes to produce the desired velocity and torsional vibration information.

Abstract: A periodic structure such as a diffraction grating is disposed on the surface of an object from which acoustic emissions are to be detected. A plane monochromatic light beam is incident on the periodic structure and forms a number of Bragg diffraction orders at predetermined angles. A detector positioned to intercept one of the diffraction orders receives light whose frequency has been Doppler shifted by surface motion on the object. A reference beam, also incident on the detector heterodynes with the Doppler-shifted beam so that the Doppler component can be recovered. In one embodiment, the reference beam is also incident on the surface and itself produces Bragg diffraction orders. The geometry produces up Doppler in the Bragg diffraction orders from one beam and down Doppler from the Bragg diffraction orders from the other beam and selected Bragg diffraction orders from both beams are heterodyned in the detector.

Abstract: A slot closure arrangement for closing the slot opening of slots in the stator of a dynamoelectric machine and for providing a restraining force against conductors in the slot. The slots have opposing notches on opposite sides of the slot adjacent the slot opening. A flat rectangular spring member is placed in the slot opening with the opposite edges of the flat spring member each terminating in one of the opposing notches. A pair of wedges with complementary tapered surfaces is inserted between the spring member and the surface of the conductor in the slot adjacent and facing the slot opening. The wedges are advanced one over the other to increase the overall thickness. The surface of the wedge engaging the spring member has a thickness at the center greater than the thickness at the edges, and the center presses the spring member outwardly when the wedges are advanced, deforming the spring member, which then provides a force through the wedges against the conductor in the slot.

Abstract: A ventilation scheme for rotor windings in a dynamoelectric machine includes passages axially extending through the axial end turn conductors of the windings. Each axially extending conductor is an integral, single bar of metal having a groove thereon which defines the passages in cooperation with the turn insulation interposed between each conductor and the underlying and overlaying conductors. Circumferential end turn conductors are mechanically and electrically attached to the axial end turn conductors by reinforcing plates. Circumferential passages through the circumferential end turn conductors allow gas to flow between an end turn region and an isolated low pressure area. The centrifugal pumping action developed by the rotation of the rotor draws gas from the end turn region through the passages and to the periphery of the rotor body.

Abstract: A method and apparatus for axially aligning axially coupled shafts of a steam turbine includes means for changing the elevation of the outboard end of each shaft. The outboard end of each shaft is rotatably supported by a bearing above a turbine foundation. Means is included for measuring the supporting force at the bearing. A strain gauge is disposed on the surface of each shaft which provides an output signal indicative of the degree of bending of that shaft. The apparatus includes means for comparing and minimizing the output signals of the strain gauges by affecting the means for changing the elevation and comparing the resultant output signals at different levels of elevation.

Abstract: In a steam turbine, apparatus for preventing rotation of a first wheel with respect to a second wheel adjacent the first wheel, wherein the first and second wheels are secured to a shaft of a rotor of the steam turbine by an interference shrink fit, comprises a key disposed in a keyway defined by and between respective hubs of the wheels. The key is exposed to ambient environment of the rotor and is spaced from the axial ends of the keyway to permit steam to flow through portions of the keyway. Key and keyway configurations for prohibiting radial movement of the key are illustrated.

Abstract: A composition for electrodeposition of an insulating mica coating onto a conducting substrate is disclosed. The composition consists essentially of mica, a water soluble anionic resin binder, an electrolyte and a polar solvent.

Abstract: For use in a pressure fed or flood lubricated bearing, there is disclosed a shaft load-bearing element (e.g., the thrust plate in a tapered land thrust bearing) preferably comprising three metallic layers including an inner layer adjacent the shaft surface of metal possessing good bearing properties; an outer layer of structural steel to provide rigidity; and an intermediate layer of copper or copper alloy sandwiched between the inner and outer layers to provide good thermal properties. The metallic layers of such a trimetallic bearing element are metallurgically bonded at the interfaces between layers to enhance heat transfer. Advantageously, a shaft load-bearing element according to the invention is substantially free from distortion and damage during handling and avoids elevated temperature problems.

Abstract: For use in a pressure fed or flood lubricated bearing, there is disclosed a shaft load-bearing element (e.g., the thrust plate in a tapered land thrust bearing) preferably comprising three metallic layers including an inner layer adjacent the shaft surface of metal possessing good bearing properties; an outer layer of structural steel to provide rigidity; and an intermediate layer of copper or copper alloy sandwiched between the inner and outer layers to provide good thermal properties. The metallic layers of such a trimetallic bearing element are metallurgically bonded at the interfaces between layers to enhance heat transfer. Advantageously, a shaft load-bearing element according to the invention is substantially free from distortion and damage during handling and avoids elevated temperature problems.

Abstract: When a torque is transmitted through a body, the body tends to twist in proportion to the torque and to the characteristics of the material. Doppler measurements made at points separated from each other on a body differ slightly due to the applied torque by the reduced motion of the body at points closer to the load. The Doppler from the two points is accumulated to thereby maintain a record of the twist and thereby the torque in the body.

Abstract: A braid clamp for generator shaft voltage and current pickup employs a compound lever for forcibly locking clamping faces of a compound action clamping block into firm contact with a portion of a metallic braid. The metallic braid is thereby secured with a portion thereof in trailing contact with a surface of the generator shaft. Provision is made for holding a substantial free end of the metallic braid ready for use but secure from accidental contact with adjacent objects. The free end may be employed for contact with the shaft by reversing the braid or may serve as a supply of braid which may be fed between the clamping faces. The compound lever is quickly openable and closeable to reduce any risk to workers servicing the metallic braid in close proximity to the rapidly rotating generator shaft.

Abstract: A semiconductive material which is formed by impregnating glass fibers or glass fabric with an organic material which is pyrolyzed in the substantial absence of oxygen and at a temperature which is above the pyrolysis temperature of the organic material, but below the boiling point or sublimation temperature of the organic material. By such pyrolysis, the organic compound is converted to substantially pure carbon deposited on the glass fibers which impart to the glass fibers semiconductive characteristics.

Abstract: A steam turbine rotor includes a plurality of turbine wheels secured to a shaft by an interference shrink fit between each wheel and a corresponding step surface on the shaft. The step surfaces have decreasing radii over a portion of the axial length of the shaft. Each wheel incudes a hub section proximate the shaft and each hub section has a shoulder portion of greater radial dimension than the radially innermost surface of the hub section. A member or finger protrudes from one shoulder and mates with a longitudinal slot on one of the step surfaces of the shaft. Relief grooves are also provided for on the shaft and hub section.

Abstract: An oil lubricated, double tilting, three pad journal bearing includes three pads asymmetrically located with respect to each other and with respect to the horizontal and vertical centerline of a horizontally disposed steam turbine shaft. Each pad has associated therewith an oil feed dam. Apparatus for lubricating supplies oil to a channel, formed by the feed dam and its corresponding pad, and the rotating shaft draws the oil from the reservoir as a film into the interstice defined by the shaft surface and the pad face.

Abstract: A terminal plate is permanently affixed to a stator frame below the connector rings. High-voltage bushings are installed in the terminal plate at the user's site. Conducting bars are employed between each connector ring and its respective high-voltage bushing. Each conducting bar terminates at a short tangential distance from a connecting portion of its related high-voltage bushing. Domed flexible straps interconnect the conducting bars with the high-voltage bushings, the domed portions of the straps oriented to absorb relative motion engendered by tangential forces on the stator core and connector rings.

Abstract: A simplified static excitation system for a fluid-cooled dynamoelectric machine comprises a potential source excitation winding disposed in the stator slots, the winding being responsive to the fundamental frequency of the generator air-gap magnetic flux. The excitation system further comprises transformer means coupling the excitation winding to rectification means which is coupled to the rotating field windings so as to provide direct electric current thereto. The transformer means is preferably disposed within the cooling fluid of the machine.