| 摘要 |
A rotary drill bit having blades with cutting elements disposed on exterior portions thereof may be formed with either a continuous cutting zone or a substantially continuous cutting zone between the last cutting element on each blade and an adjacent gage pad. Such rotary drill bits may have improved steerability during the formation of a directional wellbore and/or may experience substantially reduced wear on gage pads and/or portions of each blade adjacent to respective gage pads. For some rotary drill bits an additional cutter may be disposed in one or more gage pads adjacent to the last cutting element. For other rotary drill bits a gage cutter may be disposed between and in close proximity to both the last cutting element and adjacent portions of the associated gage pad.
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