Abstract: A downhole screw motor is designed for drilling oil and gas wells.A downhole screw motor has a stator (3) and a hollow rotor (4) having an axial passage (5) in which is mounted a flow regulator (6) having a nozzle (16). The surface of the nozzle (16) washed with working liquid is made up of two chambers disposed in series in the flow direction: an admission chamber (A) and a delivery chamber (B), the surfaces (19, 20) of the chambers being conjugated along a breaking line (21). A portion (22) of the admission chamber (A), which is adjacent to the breaking line (21), is convex with respect to the direction of flow of working liquid, and the cross-sectional area of the admission chamber (A) at the outlet thereof is smaller thereof is smaller than the cross-sectional area of the same chamber at the inlet thereof.

Abstract: The screw machine comprises consecutively mounted screw mechanisms (6, 7 and 8, 9) incorporating coaxially arranged stators (10, 12 and 14, 16) and rotors (11, 13 and 15, 17) disposed therein whose axes are offset with respect to the central axis of the stators (10, 12 and 14, 16) by the amount of eccentricity "e" of the screw mechanisms (6, 7 and 8, 9). The screw mechanisms (6, 7 and 8, 9) are grouped into modules (4, and 5) and the modules proper are grouped into blocks (3). The axes of the rotors (11, 13, 15, 17) of the screw mechanisms (6, 7 and 8, 9) in the module (4 and 5) and the modules (4, and 5) proper in the block (3) are arranged symmetrically relative to the central axis.

Abstract: A downhole motor includes a bearing unit connected to a moving section incorporating successively arranged working members--a stator and a rotor interacting with each other along profile surfaces. The like pairs of the adjacent working members are rigidly connected to each other by means of solid threaded bushings. A mounting fixture includes two mounting elements each made as two bushings interconnected by a coupling, the bushings having their profile surfaces located on the same longitudinal axis. One of the bushings is rigidly connected to the coupling, while the other bushing is mounted with the possibility of moving with respect to the longitudinal axis. A method of assembling the downhole motor is effected with the use of a pre-adjusted mounting fixture and resides in interconnecting the like working members by thread bushings ensuring the arrangement of the profile surfaces of the working members analogously to the profile surface of the single monolithic rotor and stator.

Abstract: A helical down-hole machine comprises a plurality of sections, each such section having a helical rotor and a helical stator arranged with a preselected eccentricity to form cavities of variable volume for the passage of fluid therethrough and positioned axially in series. The identical elements of these sections, rotors or stators, are rigidly interconnected. The rigid connection of at least one of these identical elements of said sections is detachable by frictionally jointing a projection provided at the end of one such element and a recess provided at the end of the adjacent element to be secured against relative angular and axial displacements in the process of rotation.

Abstract: A multistart helical planetary gear motor, comprising a stator 3 having an internal helical thread and a rotor 4 having an external helical thread and arranged eccentrically within the stator 3. The rotor 4 and stator 3 form a kinematic couple which is in permanent engagement similarly to an internal gearing, with the number of the stator teeth being greater than the number of rotor teeth by unity. The ratio of pitches of the helical threads of the stator 3 and the rotor 4 is directly proportional to the ratio of their respective numbers of teeth. The ratio of pitches of the helical surfaces of the stator 3 and the rotor 4 to their respective pitch diameters ranges substantially from 5.5 to 12.

Abstract: A casing having a gear ring formed on its inner wall and closed at each end with a cover is provided with two half-couplings arranged coaxially and having outer gear rings engaging the gear ring of the casing. A ball is disposed between the two half-couplings and the interior is filled with a lubricant. A seal is placed in the casing between each cover and the respective end face of the gear ring. Each seal is made out of an elastic material in the form of a sleeve embracing the half-coupling, and has one end abutting upon the end face of the gear ring and its other end secured to the half-coupling.

Abstract: A bottom hole motor for driving a rock-breaking tool comprises a motor unit kinematically coupled with a spindle unit. The spindle unit has a housing inside which extends a shaft connected with the rock-breaking tool and mounted in the housing with the aid of radial bearings and rings and races, said rings and races arranged coaxial with the shaft and designed to retain rolling bodies located between the rings, races and the shaft. The shaft has toroidal grooves which are in immediate contact with rolling bodies.This invention can be used for drilling and repair of oil, gas and exploratory wells.

Abstract: A valve means to be installed in a string of drill pipe above a bottom hole positive displacement motor comprises a hollow housing (1) having an inlet and an outlet for the passage of a drilling fluid therethrough, the wall of the housing having through holes (4) to communicate the interior of the housing with the annular space of the well bore. Secured in the housing (1) substantially above the through holes is a transverse plate or partition (5) provided with a plurality of calibrated openings (6) intended to produce a pressure drop. The housing (1) further accommodates a chamber (7) communicating with the through holes (4) and provided with an open face in the upper portion thereof, the chamber (7) being arranged such that through passages (10) are formed between the chamber (7) and the housing (1). The housing further comprises a sealing couple (12) intended to prevent the through holes (4) from communicating with the interior of the housing (1) in the course of drilling operation.