ROLLER BIT WITH HARD-ALLOY INSERTS Russian patent published in 2013 - IPC E21B10/16 E21B10/50 

FIELD: mining.

SUBSTANCE: proposed roller bit comprises body and rolling cutters fitted on leg pins, their rims being reinforced with teeth with converging blades at rock breaking surface and furnished with cylindrical stems, conical joint thread for connection with drilling string, and borehole bottom washing system. Working head of teeth is provided with three or four wedge-like blades. Arrangement of teeth on the body and shape parameters are selected proceeding the research conducted to reveal maximum drilling properties, dynamics of bottom drilling and durability of said teeth.

EFFECT: higher efficiency of drilling.

2 cl, 16 dwg