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Title: Eddy current inspection tool which is selectively operable in a discontinuity detection mode and a discontinuity magnitude mode

Abstract

A miniaturized inspection tool, for testing and inspection of metal objects in locations with difficult accessibility, which comprises eddy current sensing equipment with a probe coil, and associated coaxial coil cable, coil energizing means, and circuit means responsive to impedance changes in the coil as effected by induced eddy currents in a test object to produce a data output signal proportional to such changes. The coil and cable are slideably received in the utility channel of the flexible insertion tube of fiberoptic scope. The scope is provided with light transmitting and receiving fiberoptics for viewing through the flexible tube, and articulation means for articulating the distal end of the tube and permitting close control of coil placement relative to a test object. The eddy current sensing equipment includes a tone generator 30 for generating audibly signals responsive to the data output signal. In one selected mode of operation, the tone generator responsive to the output signal above a selected level generates a constant single frequency tone for signaling detection of a discontinuity and, in a second selected mode, generates a tone whose frequency is proportional to the difference between the output signal and a predetermined selected threshold level. 5 figs.

Inventors:
;
Issue Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
OSTI Identifier:
7003172
Patent Number(s):
4412177 A
Application Number:
PPN: US 6-201946
Assignee:
OAK; EDB-94-125146
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Resource Relation:
Patent File Date: 29 Oct 1980
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; EDDY CURRENT TESTING; EQUIPMENT; COAXIAL CABLES; FIBER OPTICS; LIGHT TRANSMISSION; METALS; MINIATURIZATION; PROBES; CABLES; CONDUCTOR DEVICES; ELECTRIC CABLES; ELECTRICAL EQUIPMENT; ELECTROMAGNETIC TESTING; ELEMENTS; MATERIALS TESTING; NONDESTRUCTIVE TESTING; TESTING; 420500* - Engineering- Materials Testing

Citation Formats

Petrini, R.R., and Van Lue, D.F. Eddy current inspection tool which is selectively operable in a discontinuity detection mode and a discontinuity magnitude mode. United States: N. p., 1983. Web.
Petrini, R.R., & Van Lue, D.F. Eddy current inspection tool which is selectively operable in a discontinuity detection mode and a discontinuity magnitude mode. United States.
Petrini, R.R., and Van Lue, D.F. Tue . "Eddy current inspection tool which is selectively operable in a discontinuity detection mode and a discontinuity magnitude mode". United States.
@article{osti_7003172,
title = {Eddy current inspection tool which is selectively operable in a discontinuity detection mode and a discontinuity magnitude mode},
author = {Petrini, R.R. and Van Lue, D.F.},
abstractNote = {A miniaturized inspection tool, for testing and inspection of metal objects in locations with difficult accessibility, which comprises eddy current sensing equipment with a probe coil, and associated coaxial coil cable, coil energizing means, and circuit means responsive to impedance changes in the coil as effected by induced eddy currents in a test object to produce a data output signal proportional to such changes. The coil and cable are slideably received in the utility channel of the flexible insertion tube of fiberoptic scope. The scope is provided with light transmitting and receiving fiberoptics for viewing through the flexible tube, and articulation means for articulating the distal end of the tube and permitting close control of coil placement relative to a test object. The eddy current sensing equipment includes a tone generator 30 for generating audibly signals responsive to the data output signal. In one selected mode of operation, the tone generator responsive to the output signal above a selected level generates a constant single frequency tone for signaling detection of a discontinuity and, in a second selected mode, generates a tone whose frequency is proportional to the difference between the output signal and a predetermined selected threshold level. 5 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1983},
month = {10}
}