| 摘要 |
A drill bit comprising: a cutting section comprising gage cutters, wherei n in the cutting section is a first end of the bit, and wherein the cutting section has a full gage diameter; a heel section comprising a blade, wherein the heel section is at an end of the drill bit opposite the cutting section , and wherein a diameter of the heel section is a full gage diameter, wherei n the blade has a high spiral around the drill bit; and a clearance section between the cutting and heel sections, wherein the clearance section compris es a diameter less than full gage, and wherein clearance section extends fro m the gage cutters of the cutting section to the blade of the heel section.
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