ROLLING DRILLING BIT Russian patent published in 2013 - IPC E21B10/22 

FIELD: mining.

SUBSTANCE: rolling drilling bit includes legs with trunnions, on which there installed are roller cutters mounted by means of two conical roller bearings, the inner races of which are pressed on the trunnion, plate spring and adjusting ring with radial holes for pins to fix the adjusting ring relative to the trunnion, which are installed between roller bearings, and support sealing assembly installed on the side of the trunnion base. Inner races of roller bearings in the zone of trunnion loaded part are located with a gap relative to external trunnion surface; at that, gap has segmented shape in its cross section. Segmented gap between trunnion and race can be formed with a groove made on internal surface of race, or with trunnion provided in loaded part with the radius exceeding the radius of internal race surface.

EFFECT: improving bit operating efficiency; increasing the operational life of its support.

4 cl, 3 dwg