DRILLING BIT Russian patent published in 2012 - IPC E21B10/26 E21B7/08 

FIELD: mining.

SUBSTANCE: drilling bit includes a housing, cutting part, connecting devices to connect bit to the source of rotary movement and force application to the bit in order to force its cutting part into drilled out material. Also drill bit includes calibrating area which is between the mentioned cutting part and connecting devices, at that calibrating area includes at least one link capable of movement between the first position, in which calibrating area is restricted with supposed tubular surface of constant cross-section being coaxial to the axis of rotation, and the second position, in which part of this link is arranged radially inwards against the axis of rotation from its position while the mentioned link is located in the first position, at that when the mentioned link is in the mentioned second position calibrating area is restricted with supposed three-dimensional surface of conic section. Also drill bit includes at least one drive, at that each mentioned link is mechanically connected to the drive so that each link is capable of movement between the mentioned first and second positions using the drive.

EFFECT: effective drilling of both inclined and straight wells using one drill bit, possibility to change well direction, stabilise movement of drill bit, reduce wear of drill bit calibrating part.

26 cl, 4 dwg