Drilling structure with non-axial gage
AssigneeBaker Hughes Incorporated
InventorsGordon A. Tibbitts, James A. Norris
Life of this patent
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Abstract
A drill bit and method of drilling a subterranean formation are disclosed in which the drill bit is configured with a non-axial gage portion of a bit body. The non-axial gage portion of the bit body presents a peripheral profile which is not parallel to the centerline of the bit body to provide a contact area for engagement of the sidewall of the borehole by at least one cutting element carried by the non-axial gage portion to enlarge the borehole from a first diameter cut by cutting elements on the bit face. The configuration of the drill bit lessens loading on the cutting elements of the drill bit, facilitates maneuverability of the drill bit downhole and enhances steerability of the drill bit.
Claims40
A rotary drilling structure for drilling a borehole in a subterranean formation, comprising:
- a body having a centerline and at least one cutting element at a periphery thereof being positioned to cut a borehole in a formation to a first gage diameter;
- at least one non-axial gage portion on said body defining a peripheral profile exhibiting a substantially constant cross-sectional area transverse to said centerline throughout at least a portion of a longitudinal extent of said at least one non-axial gage portion and oriented along at least one direction disposed at an acute angle to said centerline;
- and
- at least one contact area located on said at least one non-axial gage portion at a position radially beyond said first gage diameter and bearing at least one cutting element thereon positioned for engagement with said formation.
A rotary drill bit for drilling a borehole in a subterranean formation, comprising:
- a bit body having a centerline, a crown portion including a face and a shank portion;
- said face having at least one cutting element at a periphery thereof being positioned to cut a borehole in a formation to a first gage diameter;
- at least one non-axial gage portion on said bit body defining a peripheral profile exhibiting a substantially constant cross-sectional area transverse to said centerline throughout at least a portion of a longitudinal extent of said at least one non-axial gage portion and oriented along at least one direction disposed at an acute angle to said centerline;
- and
- at least one contact area located on said at least one non-axial gage portion radially beyond the first gage diameter and bearing at least one cutting element thereon positioned for engagement with the formation.
Dependencies are inferred from the claim text.