The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 19, 2000
Filed:
Sep. 09, 1998
Macmillan M Wisler, Kingwood, TX (US);
David M Schneider, Spring, TX (US);
Baker Hughes Incorporated, Houston, TX (US);
Abstract
An NMR logging tool has a conducting permanent magnet with its axis parallel to the borehole axis to produce a static field in a portion of the formation surrounding a borehole that is parallel to the borehole axis. A dipole RF antenna with the dipole axis orthogonal to the borehole axis is used to produce an RF magnetic field orthogonal to the static field. The same antenna is used to receive the echo signals from excited nuclei in the formation. A number of gapped ferrite strips on the permanent magnet shield the permanent magnet from the RF field and enhance the RF field. Another form of the tool may be used for making Measurement-While-Drilling measurements with the permanent magnet set in a recess on a drilling collar.