Perm engineers from "PZTO Titan" company have developed a new design for a gerotor hydraulic motor for directional drilling. The power unit is designed to operate at drill string rotation speeds of up to 120 rpm and more.
For existing power units, exceeding 80 rpm can sharply reduce service life due to fatigue cracks in threaded connections.
Therefore, the main change in the innovators' scheme affected the lower part of the engine. A separate centralizer with a tilting radial support was installed on the bit side, and the bit shaft was connected to the spindle section shaft by a special drive coupling.
This reduces the distance from the tilt point to the lower end of the bit shaft – the so-called "lower arm" of the curvature. This approach reduces resistance and stress in the lower part of the drill string, and the engine itself gains greater service life and reliability.
Separately, the developers isolated the drive coupling cavity and filled it with lubricant. This should increase its service life while maintaining the supply of circulating fluid through the bit to remove drilled rock.