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. 07, 2004
Filed:
Jul. 31, 2002
Ted Dimitroff, Columbia, MO (US);
Paul W. Knecht, Perry, OK (US);
The Charles Machine Works, Inc., Perry, OK (US);
Abstract
A method and apparatus for boring a close tolerance on-grade subsurface borehole. A downhole tool assembly for use with a dual member drill string comprises a directional boring tool. The dual member drill string comprises an outer member and an inner member disposed within the outer member and rotatable independently of the outer member. The downhole tool assembly permits the directional boring tool to be connected to the inner member of the drill string. Rotation of the inner member of the drill string causes rotation of the boring tool. The borehole is drilled in a straight manner by rotating the boring tool with the inner member of the drill string and simultaneously advancing the drill string through the earth. The borehole direction is changed by orienting the directional boring tool with the inner member of the drill string and then advancing the drill string without rotation.