WELL DRILLING DEVICE Russian patent published in 2008 - IPC E21B4/02 

FIELD: mining.

SUBSTANCE: the invention concerns mining gerotor type motors and can be applied in drilling of oil, gas and exploration wells. The device includes screw gerotor device with immobile stator with elastic cover and mobile hollow rotor. LH screw thread is made on the inner surface of stator and outer surface of hollow rotor, the number of stator and rotor pitches differing by one. Inner surface of the hollow rotor features elastic cover with the second solid rotor mounted eccentrically inside. LH screw thread is made on the inner surface of the hollow rotor with elastic cover and outer surface of the second solid rotor, the number of hollow rotor pitches differing by one.

EFFECT: improved well drilling efficiency, increased mechanical drilling rate per bore bit.

1 dwg