SCREW POSITIVE-DISPLACEMENT MOTOR WITH TURBINE ACTIVATOR Russian patent published in 2003 - IPC

FIELD: mining industry. SUBSTANCE: invention refers to downhole hydraulic motors which set roller bits in motion to break faces of shafts of drilled holes. Salient feature of invention consists in design of multistart screw motor that includes spindle carrying ball pivot, radial supports and disc labyrinth throttle seal and working section comprising screw positive-displacement pair and up to sixty stator and rotor stages of pressure of turbine-activator of positive-displacement pair. Rotor stages of pressure of turbine-activator are fixed immobile on shaft of working section together with rotor of screw positive-displacement pair with the help of rotor nut and stator stages of pressure of turbine-activator are fixed immobile in body of working section together with stator of screw positive-displacement pair with the use of lower connecting sub. Body of working section houses up to six stator shock absorbers-limiters of lateral vibration of shaft of working section which are fixed immobile. Clearances between blade rims of stator stages of pressure of turbine and hubs of rotor stages of pressure of turbine corresponding to them are closed by radial-face laminated rubber-metal seals. Clearances between ends of blades of each rotor stage of pressure of turbine and hubs of stator stages of pressure of turbine corresponding to them are closed by radial fillet or by confuser compression of each stator stage of pressure of turbine placed above on side of its largest wetted perimeter. Chord of profile of blades of stator is arranged at angle from 35 to 55 degrees with plane perpendicular to its longitudinal axis, at same time chord of profile of blades of rotor stages of pressure of turbine has inclination angle from 60 to 90 degrees with plane perpendicular to their longitudinal axis and preferable direction of inclination of chord of profile is right-hand screw. EFFECT: effective realization of concept of shortened downhole motor with large margin of torque on it shaft and long service life under relatively low pressure differential on its working elements. 4 cl, 6 dwg