GEROTOR HYDRAULIC MOTOR Russian patent published in 2018 - IPC E21B4/02 E21B7/08 E21B29/06 

FIELD: drilling of soil or rock.

SUBSTANCE: invention relates to hydraulic drives for rotary drilling placed in a well, namely for milling a window cut in a casing string in a well bore and drilling lateral channels for perforating a productive interval. Gerotor hydraulic motor contains front and rear sections, made in the form of tubular housings, fastened with an intersectional sub with threads on its edges, with its own screw gerotor mechanism located inside each section, including a fixed inside of the front, as well as the back sections of the lining of the elastomer with internal helical teeth and an eccentrically located rotor with external helical teeth, the rotors are rotated by pumping fluid, and also contains an intersectional drive shaft bonded to the rotors of the front and rear sections, and also contains a spindle section comprising a spindle section body, a spindle section shaft mounted in an axial bearing, made in the form of a radial multi-row bearing, as well as in an upper and lower radial slide bearing, and also contains a spindle sub with threads on its edges, fastened to the spindle and front sections, and the spindle section drive shaft, fastened to the front section rotor and the spindle section shaft. Intersectional and spindle subs are made, each with one fixed skew angle of the axes of the threads at its edges. Axis of the threads on the edges of the intersectional and spindle subs are located in the same plane and have the same direction of skew. Intersectional drive shaft is made with hinged joints, including two couplings, each of which covers the edge of the intersectional drive shaft, and between each coupling and the edge of the intersectional drive shaft there is a row of balls mounted by one side in the hemispherical depressions of the intersectional drive shaft, and the other side in the longitudinal semi-cylindrical grooves of the coupling. Skew point of the axes of the threads on the edges of the intersectional and, respectively, spindle sub is located, each, in the plane of the thrust end of the intersectional and, accordingly, spindle sub, directed to the thrust end of the rear body and, accordingly, the front engine sections, length L of the housing of the front and rear sections and the distance K between the stop ends of the intersectional sub are related by the relation L=(7÷10)K, and the length N between the stop ends of the spindle section body and the distance T between the stop ends of the spindle sub are connected by the relation N=(2.5÷4.5)T.

EFFECT: increase of the resource and reliability of the engine is provided for milling cutting the window in the casing string in the wellbore and drilling the side channels for perforating the productive interval and increasing the oil well flow rate.

3 cl, 4 dwg