ROLLING BIT WITH SEALED SUPPORT Russian patent published in 2013 - IPC E21B10/24 

FIELD: oil and gas industry.

SUBSTANCE: rolling bit with a sealed support comprises legs, lubrication reservoirs tightly installed and rigidly fixed in them, elastic membranes with a radial and end metal frame, end circular centring washers, end pressing elements, conical threaded plugs, side bores on walls of reservoirs with through holes for lubricant release from the cavity of the reservoir into the lubricating system, and also a system of channels and holes for supply of a drilling mud under elastic membranes. At the side of release from seats in legs there are adjustment and stop nuts installed on the thread with holes at the ends for a socket wrench, which control forces for clamping of the elastic collar of the membrane, the end clamping element and the threshold of actuation of excessive pressure relief in the system of bit lubrication.

EFFECT: improved reliability of operation of rolling bits, their reservoirs, possibility to adjust a threshold for actuation of excessive pressure relief with regard to depth of suggested drilling interval.