MECHANISMS FOR FEEDING DRILL BITS Russian patent published in 2018 - IPC E21B19/08 

FIELD: drilling of soil or rock.

SUBSTANCE: invention relates to drilling techniques, in particular to hydraulic mechanisms for feeding drill bits. Mechanism for feeding the bit is telescopic system installed between drill string and bottom hole assembly, and includes prefabricated cylindrical body with internal splines, hollow rod with piston in upper part and outer splines cooperating with body internal slots. Stem and piston have the same outer diameters forming gap with inner surface of cylindrical body. On outer surface of piston and on inner surface of lower part of the body, sealing assemblies are installed forming together with body inner surface and outer surface of rod is sealed chamber filled with oil, in which there is splined joint.

EFFECT: technical result is high reliability of device.

1 cl, 2 dwg