Horst G Delorenzi

US Patent:

47516577, Jun 14, 1988

Filed:

Jul 8, 1985

Appl. No.:

6/752883

Inventors:

Imdad Imam - Schenectady NY
Horst G. DeLorenzi - Scotia NY

Assignee:

General Electric Company - Schenectady NY

International Classification:

G01M 700

US Classification:

364508

Abstract:

Axial cracks in the rotor assembly of a variety of rotating machinery are detected while the rotor is being rotated, by sensing mechanical vibrations of the rotor at a location along the length thereof to produce a corresponding rotor vibration signal. A background vibration signal representing the vibration response at an earlier time is provided, as well as a monitor vibration signal representing the vibration response of the rotor at the time the monitor signal is obtained. A speed-dependent first harmonic difference signal is found by vectorially subtracting the first harmonic of the background vibration signal from the first harmonic of the monitor vibration signal. The relationship between the amplitude of the difference signal and the rotational speed of the rotor is then determined for rotational speeds away from the speed at which vibrational resonance occurs, with a relationship wherein the difference signal is proportional to the fourth power of the rotational speed being indicative of the presence of an axial crack in the rotor assembly. Histogram techniques improve the signal-to-noise ratio of the background vibration signal and of the monitor vibration signal. The vibration response of the rotor assembly at rotational speeds near the resonance speed may be utilized in conjunction with the response at speeds away from the resonance speed, in order to confirm the presence of a rotor crack.

US Patent:

62312871, May 15, 2001

Filed:

Feb 28, 2000

Appl. No.:

9/514741

Inventors:

William Lee Herron - Greer SC
Srihari Balasubramanian - Guilderland NY
Horst Gunther DeLorenzi - Scotia NY
Suryaprakash Ganti - Albany NY

Assignee:

General Electric Co. - Schenectady NY

International Classification:

F16B 3706

US Classification:

411427

Abstract:

A rotor tie bolt nut includes a nut body having a threaded center hole therein; a first peripheral surface on one side of the center hole that spans the center hole and extends in opposite directions to define a pair of wing sections; and a pair of buttress sections supporting the wing sections; the buttress sections having second and third peripheral surfaces connected to opposite ends, respectively, of the first peripheral surface, and to each other by a radiused surface on an opposite side of the center hole.