General Electric Company

Alexander Gabriel Beckford

Eric Steven Buskirk

Ronald Joseph Zawoysky

Madhu Bharadwaj

Samir Armando Salamah

Henry August Scarton

Emil Donald Jarczynski

Benjamin Alber Mancuso

Kyle Richard Wilt

Gary Randall Barnes

Siddharth Navinchandra Ashar

Sairam Sundaram

Sadeo Ramtahal

Anthony Rigosu

Srikanth Akkaram

Robert Gerald Hamilton

Mandar K Chati

William H Boardman

Klaus Werner Sommerlatte

Donald Alden VanSlyke

Rajiv Rajan

Nathaniel Philip Marshall

Devon Walter Story

John Peter Hoffman

A method of servicing, or repairing a crack in, a dovetail portion of a dynamoelectric machine's rotor coil slot wall. The coil slot wall includes a radial entry surface connected to an inwardly tapered surface. The inwardly tapered surface is connected to an intermediate radial surface. A machining step machines a first groove in the radial entry surface and inwardly tapered surface. The first groove extends linearly to the intermediate radial surface. The first groove is configured so that a smooth and linear surface is created along a length of the first groove. A second machining step machines a second groove in the intermediate radial surface in an orientation substantially perpendicular to the first groove. A portion of the second groove contacts a portion of the first groove. At least one of the first groove and the second groove are configured to remove damaged material from the coil slot wall.

Generator rotor fretting fatigue crack repair method

Systems and devices for thermodynamically regulating portions of a dynamoelectric machine are disclosed. In one embodiment, a fan assembly element includes: an axially inner shroud segment configured to form a portion of an annular assembly about a rotor of a dynamoelectric machine, wherein the axially inner shroud segment includes a rotor hub interface configured to physically connect to a complementary portion of a rotor hub; a set of fan blades physically connected to and extending axially from a face of the axially inner shroud segment; and an axially outer shroud segment physically connected to the set of fan blades.

Segmented fan assembly

A solution is provided for tuning the frequency of a torsional mode of interest of a rotating body (such as a generator rotor torsional mode) by adding a detuner to act as an undamped torsional vibration absorber. The detuner may be coupled to an overhung shaft extending from the rotating body. The detuner may be modular, therefore weight can be added or subtracted easily from the detuner in order to adjust the stiffness and/or inertia of the overhung shaft. This change in stiffness and/or inertia yields a torsional frequency of oscillation in the overhung shaft substantially similar to the natural frequency of the torsional mode of interest of the rotating body, therefore forcing the frequency of the torsional mode of interest of the rotating body above or below its torsional natural frequency.

Detuner for tuning torsional mode of a rotating body

Re-machining a generator rotor tooth dovetail results in a transition zone at an end of the partial re-machined cut, between a newly cut load surface and an original load surface of the rotor tooth. The transition zone is susceptible to stresses that may adversely affect the fatigue strength of the rotor tooth. These stresses can be reduced by the steps of (a) forming at least one axial undercut stress relief groove across the transition zone between the newly cut load surface and the original load surface, (b) cutting and shaping a wedge that will fit in the transition zone, and (c) securing the wedge across the transition zone.

Method for reducing stresses resulting from partial slot dovetail re-machining for generator rotor

A method to repair a rotor system having a coupling, a coupling keyway, a shaft, a shaft keyway, and a key. The method may include the steps of machining a shaft relief on the shaft adjacent to the coupling, providing fillet radii to the coupling keyway and the shaft keyway, adding a fretting resistant button to the key, machining a keyway relief on the shaft keyway, and machining a coupling relief on the coupling adjacent to the shaft. The method further may include the step of machining the key, the step of positioning dowels between the coupling and the shaft, and the step of shot-peening the coupling keyway and the shaft keyway.

Systems and methods for repairing a rotor system keyway

A method of repairing a crack in at least one side of a dovetail portion of a generator rotor coil slot wall, the dovetail portion having received at least two axially adjacent steel wedges and including at least a radial entry surface, an inwardly tapered surface and an intermediate radial surface, the method comprising a) machining a groove at least partly along the inwardly tapered surface to remove damaged material from the coil slot wall; and b) replacing the at least two axially adjacent steel wedges.

Generator rotor fretting fatigue crack repair

A rotating electrical machine with a reverse flow ventilation system is constructed with one or more discharge ducts at the center of the stator core to reduce the air gap pressure and promote more uniform cooling. In a second embodiment, discharge ducts are provided axially displaced from the center line of the core. In another embodiment, end region cooling of the conductor bars is enhanced by a series-parallel flow path constructed with the use of baffles and an apertured plate. In a final embodiment, both stator core center discharge ducts and series-parallel flow end region cooling are incorporated in the same machine.

Reverse flow ventilation system with stator core center discharge duct

Growing community of inventors

Glenville, NY, United States of America

Alexander Gabriel Beckford