DIAMOND TUBULAR BIT Russian patent published in 2011 - IPC B23B51/04 B28D1/14 

FIELD: process engineering.

SUBSTANCE: proposed bit comprises tubular body and discontinuous working part with intermittent cutting edge made up of diamond-containing coat on tubular body. Bit working part has through cutout oriented axially to form one slot in the plane of each cross section of bit working part. Said cutout is made over entire length of the bit working part, or is formed by, at least, two axially-oriented fragments shifted relative to each other for length of one fragment. Note here that said fragments are uniformly distributed along circumference relative to bit axis.

EFFECT: higher efficiency of small-diametre tubular bits in making deep holes.

3 cl, 8 dwg