| 摘要 |
<p>A drill bit comprising: a cutting section comprising gage cutters, wherein 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, wherein the blade has a high spiral around the drill bit; and a clearance section between the cutting and heel sections, wherein the clearance section comprises a diameter less than full gage, and wherein clearance section extends from the gage cutters of the cutting section to the blade of the heel section.</p> |
