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:
Jan. 10, 2006
Filed:
Oct. 04, 2004
Xiao Ming Tang, Sugar Land, TX (US);
Douglas J. Patterson, Houston, TX (US);
Tsili Wang, Katy, TX (US);
James V. Leggett, Iii, Houston, TX (US);
Vladimir Dubinksy, Houston, TX (US);
Xiao Ming Tang, Sugar Land, TX (US);
Douglas J. Patterson, Houston, TX (US);
Tsili Wang, Katy, TX (US);
James V. Leggett, III, Houston, TX (US);
Vladimir Dubinksy, Houston, TX (US);
Baker Hughes Incorporated, Houston, TX (US);
Abstract
The logging tool of this invention includes a transmitter conveyed on a drilling collar for exciting a quadrupole signal in a borehole being drilled by a drill bit and a receiver for receiving the signal. The transmitter is operated at a frequency below the cut-off frequency of the quadrupole collar mode. The received signal consists primarily of the formation quadrupole mode which, at low frequencies, has a velocity that approaches the formation shear velocity. The transmitter, in one embodiment, consists of eight equal sectors of a piezoelectric cylinder mounted on the rim of the drilling collar. The value of the cut-off frequency is primarily dependent on the thickness of the drilling collar. Alternatively, the transmitter may be operated to produce both the collar mode and the formation mode and a processor may be used to filter out the collar mode.