HYDRAULIC DOWNHOLE MOTOR

FIELD: drilling of soil or rock.SUBSTANCE: invention relates to hydraulic drives for rotary drilling located in wells. In the method, the downhole motor comprises a tubular body disposed within it by a helical gerotor mechanism including a coaxially arranged elastomeric plate in the body and a rotor mounted inside the body, the rotation of which is provided by pumping supply of the fluid, the body of the spindle section with the shaft located inside it mounted on an axial support made in the form of a ball-bearing thrust radial multi-row bearing, as well as on the upper and lower radial sliding supports consisting of the outer and inner bushes located in the body of the spindle section and, accordingly, on the spindle section shaft, the shaft of the spindle section is fastened at the input by the drive shaft with the motor rotor, and the output is fastened to the chisel, the motor and spindle sections are fastened together with a threaded sub-adapter, and the lower radial support of the spindle section is fixed with a nipple, the body of the spindle section and the nipple are fixed with a common thread. Further, the body of the spindle section contains a belt of increased stiffness, characterized by the implementation of the wall of the body of increased thickness, located upstream of the fluid from the plane of the section of the body of the spindle section along the valley of the first mating thread of the pin to the plane of the cross-section of one of the downstream rows of balls of a ball-bearing thrust-radial multi-row bearing. Moment of inertia Jm of the cross section of said reinforced stiffener belt in the spindle section body and the moment of inertia Jv in the cross section of the spindle section shaft in the plane of each of the rows of the ball-bearing thrust-radial multi-row bearing located upstream of the fluid from the increased stiffness belt in the body of the spindle section are connected by the relation: Jm=(6.25÷8.25) Jv. Diameter Dm of balls, outer diameter Dn of bearing and inner diameter Dv of the bearing are connected by the relation: Dm=0.5(Dn-Dv)-(0.155÷0.235) (Dn-Dv), and the number of balls in each row of bearings, the diameter Dm of the balls and the diameter Dcp of the bearing in the center of the balls are connected by the relation: z=[πDcp/Dm]-1, where π=3.14159... - a mathematical constant equal to the ratio of the circumference to its diameter, and the z number of balls in each row of bearings is rounded to an integer.EFF