Electricity: measuring and testing – Magnetic – Magnetic sensor within material
Reexamination Certificate
1998-09-17
2001-01-16
Strecker, Gerard (Department: 2862)
Electricity: measuring and testing
Magnetic
Magnetic sensor within material
C324S226000, C324S262000, C073S866500
Reexamination Certificate
active
06175234
ABSTRACT:
TECHNICAL FIELD
The present invention relates to the inspection of hollow cylindrical structures, such as bolt holes, and, more particularly, to a device for holding and aligning a probe for inspecting such structures.
BACKGROUND OF THE INVENTION
Eddy current inspection probes are used for crack detection in bolt holes and the like. With the advent of high speed turbomachinery, a number of critical rotating parts are being specifically tested for cracks and related defects in their bolt hole walls. Various testing equipment have been developed to inspect for metal cracks in critical locations. Eddy current inspection is a commonly used technique for detecting discontinuities or flaws in the surface of components of a gas turbine engine.
The current method to inspect a bolt hole initially requires aligning a bolt hole inspection machine to the first bolt hole to be inspected. The existing bolt hole inspection machine is started and the system inspects a first bolt hole and automatically indexes to and inspects each subsequent bolt hole. However, in the course of manufacturing various components, bolt holes can vary slightly in spacing from a previous hole, by approximately 0.015″ in any direction. It is critical with bolt hole inspection that the probe be held in a vertical position. If the alignment is at all inaccurate, the lift-off of the probe from inside of the bolt hole will give a (false) signal that the bolt hole will fail. The hole will have to be realigned and rerun to see if it will pass the limits that are set up for that part type. Every hole that fails on a part requires an additional three or more minutes to realign the probe to the hole and restart the inspection process. On average, an additional one to two hours is spent realigning the probe and restarting the inspection device due to false signals.
It would be desirable to be able to provide accurate alignment of the bolt hole inspection probe, compensating for variations in the spacing between holes. The objects, features and advantages of the present invention will become more readily apparent in the following description when taken in conjunction with the appended drawings.
SUMMARY OF THE INVENTION
The present invention provides a self-aligning probe holder whereby the probe is allowed to float in all directions to compensate for variations in spacing between holes. This allows the probe to stay vertical at all times, with very little lift off occurring.
In accordance with the present invention, an intermediary device is provided between an eddy current bolt hole inspection machine and an associated eddy current probe to properly align the probe in each bolt hole to be inspected. A first end of the device is attachable to the eddy current bolt hole inspection machine, and a second end, having a tightening bolt, is attachable to the eddy current probe. A collet associated with the second end of the device secures the probe to the device when the tightening bolt is tightened subsequent to the second end accepting the eddy current probe. An adjustable flange means has a first portion separated from a second portion via a spring wave washer to allow the second portion to move left to right and front to back, relative to the first portion.
In the drawings as hereinafter described, a preferred embodiment is depicted; however, various other modifications and alternative constructions can be made thereto without departing from the true spirit and scope of the invention.
REFERENCES:
patent: 3234455 (1966-02-01), Idel
patent: 3600678 (1971-08-01), Garrett et al.
patent: 3718855 (1973-02-01), Rogel et al.
patent: 4134067 (1979-01-01), Woodbury
patent: 4827771 (1989-05-01), Cary et al.
patent: 4991439 (1991-02-01), Betts
patent: 5023549 (1991-06-01), Dau et al.
patent: 5136240 (1992-08-01), Geier et al.
patent: 5174165 (1992-12-01), Pirl
patent: 5279168 (1994-01-01), Timm
patent: 5424639 (1995-06-01), Meiffren et al.
patent: 5442286 (1995-08-01), Sutton, Jr. et al.
patent: 5600240 (1997-02-01), Mikhailovich et al.
patent: 5834937 (1998-11-01), Burris
patent: 5955684 (1999-09-01), Gravel et al.
Day David E.
Granger Janice L.
Granger, Jr. Carl
Hewton Thomas B.
General Electric Company
Granger Janice L.
Gressel Gerry S.
Hess Andrew C.
Strecker Gerard
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