摘要 |
A drill bit insert has a cylindrical barrel, a bevel on one end, an interface therebetween, and a cutting tip opposite the bevel. The bevel and interface contact the entrance to a hole in the drill bit and facilitate the transition of the barrel into the hole. A high quality surface finish on the bevel and interface enhance the durability and retention of the insert in the drill bit. The surface finish on the insert is produced by polishing it with a diamond lapping film. The insert is rotated between three rollers as the lapping film passes over its surface. One of the rollers and the film conform to the axial profile of the insert as each element rotates so that the interface, bevel, and barrel of the insert are simultaneously polished.
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