CONE DRILLING BIT (VARIANTS) Russian patent published in 2007 - IPC E21B10/00 

FIELD: rock-cutting tools, particularly cone bits for well drilling.

SUBSTANCE: drilling bit comprises body with conical nipple having inner channel and outer thread. The body is provided with flushing channels and grooves made in inner surface. Drilling bit also has legs with cutters fixedly secured in body grooves. Outer diameter of thread provided on minor base of drilling bit nipple cone d is related to outer (nominal) drilling bit diameter D as d/D=0.2-0.6. Drilling bit made in accordance with the second embodiment comprises body with conical nipple having inner channel and outer thread. The body also has flushing channels and grooves created in outer surface thereof and legs with cutters fixed in body grooves. Formed inside the nipple are n channels, wherein n≥2. Outer diameter of thread provided on minor base of drilling bit nipple cone d is related to outer (nominal) drilling bit diameter D as d/D=0.2-0.6.

EFFECT: increased drilling bit efficiency, reliability and manufacturability.

3 cl, 2 dwg