Electricity: measuring and testing – Magnetic – With means to create magnetic field to test material
Patent
1995-06-07
1997-03-11
Strecker, Gerard R.
Electricity: measuring and testing
Magnetic
With means to create magnetic field to test material
324220, 324225, 324232, 324240, G01N 2790
Patent
active
056105177
ABSTRACT:
A sheet inducer carrying a uniformly distributed ac current induces a sheet eddy current generally parallel to a generally smooth surface of an electrically conductive object. A magnetometer, preferably a superconducting quantum interference device (SQUID) magnetometer, detects the component of a magnetic field generally perpendicular to the generally smooth surface resulting from disturbances in the sheet eddy current caused by a flaw. Through appropriate selection of the phase angle between the detector signal and the applied current, the response can be adjusted to suppress surface flaws and enhance detection of flaws below the surface. The sheet eddy current is induced in multiple directions to detect flaws of all orientations and at multiple frequencies to refine determination of the size, shape, and depth of a flaw. An elongated solenoid is used to induce a circumferential sheet eddy current in elongated objects such as tubes and rods, and a current-carrying rod is used to induce a longitudinal sheet eddy current in an elongated tubular object.
REFERENCES:
patent: 2881387 (1959-04-01), Wood
patent: 3255381 (1966-06-01), Tompkins et al.
patent: 4087749 (1978-05-01), McCormack
patent: 4482865 (1984-11-01), George, Jr.
patent: 4594549 (1986-06-01), Smith et al.
patent: 4625167 (1986-11-01), Fitzpatrick
patent: 4706021 (1987-11-01), Chamuel
patent: 4755752 (1988-07-01), Fitzpatrick
patent: 4982158 (1991-01-01), Nakata et al.
patent: 5004724 (1991-04-01), De
patent: 5053704 (1991-10-01), Fitzpatrick
patent: 5109196 (1992-04-01), Wikswo, Jr.
patent: 5258708 (1993-11-01), Sadeghi et al.
patent: 5293119 (1994-03-01), Podney
Ma Yu P.
Wikswo, Jr. John P.
Strecker Gerard R.
Vanderbilt University
Westerhoff Richard V.
LandOfFree
Method and apparatus for detecting flaws below the surface of an does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for detecting flaws below the surface of an, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for detecting flaws below the surface of an will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-446091