Patent ID: 6533052
Filing Date: 2003-03-18
Classification: E21B

Abstract:
A drill bit for directional boring, comprising:a bit body having a frontwardly facing, circular main cutting surface having a number of main cutting teeth disposed thereon; a gage cutter extending radially outwardly from the main cutting surface, which gage cutter mounts at least one frontwardly facing gage cutting tooth thereon suitable for cutting in a circle during straight boring and over an angle defined by less than a full rotation of the bit in order to steer the bit; and a heel on an outer side surface of the bit body at a position opposite to the gage tooth, which heel provides a reaction surface for the gage cutter; wherein the bit body and gage cutter have a nearly circular side profile along a front portion thereof such that a maximum radial clearance between the side profile and a side wall of a hole being drilled is not greater than 10 percent of the radius of a circle cut by the gage tooth.