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:
Sep. 24, 1996
Filed:
Dec. 06, 1994
Gary M Thigpen, Houston, TX (US);
William H Sherwood, Jr, Spring, TX (US);
Coy M Fielder, Cypress, TX (US);
Baroid Technology, Inc., Houston, TX (US);
Abstract
A drag bit having a plurality of blades or ribs on its end face has one or more pockets milled into the top surfaces of said blades. A tungsten carbide button or insert is positioned at the gauge diameter to reduce impact on the gauge diameter cutter in each of the fibs. The tungsten carbide button extends to the borehole gauge diameter to stabilize the bit within the borehole to limit bit whirling. The tungsten carbide button extends just forward of at least the final cutter assembly with respect to the direction of bit rotation to take the impact instead of the cutters. An additional tungsten carbide button or a shaped cutter is used along the blades in line with PDC cutting assemblies for limiting the penetration of the PDC cutting assemblies to thereby limit bit whirling or tilting instabilities. A shaped PDC cutter has a beveled edge with a bevel angle greater than the backrake angle of the PDC cutter so that engagement with the borehole wall is made with the tungsten carbide body rather than the PDC cutting portion to thereby function as a penetration limiter. As the bit wears, the PDC cutting portion begins to engage the formation in the same manner as the other PDC cutting assemblies.