St. Petersburg Mining University of Empress Catherine II has developed a new downhole motor with a bi-rotor mechanism of action. The design is based on two screw downhole units installed in series.
The upper section transmits rotation through a special removable adapter to the body of the lower motor, and both mechanisms together increase the rotational speed of the rock-cutting tool.
The main difference of the solution is that the lower motor no longer remains completely stationary. Its stator is rigidly connected to the body, which receives rotation from the upper section. A longitudinal channel is made inside the adapter, through which drilling fluid enters the injection chamber of the lower motor.
The design includes rotors, stators, spindle and transmission shafts, as well as articulated joints for torque transmission.
The development is intended for drilling directional and horizontal wells with a large deviation from the vertical.