RU2377381C1 - Downhole motor - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention relates to oil-and-gas industry, particularly to designs of downhole motors designed to drive rock-breaking tools. Proposed downhole motor comprises housing with working fluid pressure chamber and rotor mounted inside said housing to run in bearings therein. Rotor has inner chamber divided by a web into top and bottom spaces. The latter communicates with aforesaid housing chamber via radial holes made in rotor bottom wall, while the former communicates with nozzles arranged on rotor outer surface via radial holes made in rotor top wall.

EFFECT: downhole motor does not posses reactive moment and requires no housing fixation in operation.

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Description

The invention relates to techniques for constructing wells and can be used in the oil and gas industry as a downhole motor for driving a rock cutting tool.

Known screw downhole motor [Abubakirov V.F. et al. “Drilling equipment”: Reference: in 2 vols. T. 2. "Drilling tool." - M. OJSC "Publishing House" Nedra ", 2003 pp.109-110], containing the stator of the engine with cavities adjacent at the ends to the chambers of high and low pressure, a rotor-screw, through which the torque is transmitted to the actuator.

The downhole motor is known [RF patent No. 2283936, class. ЕВВ 4/02, publ. 09/20/2006 bull. No. 26], comprising a housing with a chamber for pumping a working agent, mounted in the cavity of the housing on bearings of the rotor.

The disadvantages of the known downhole motors is that the rotor during rotation interacts through the working fluid with the stator (housing), which leads to the appearance of a reactive moment on the housing and, as a result, there is a need to fix the stator (housing) during engine operation.

The objective of the invention is the creation of a downhole motor in which the housing will be unloaded from the action of the reactive moment.

The problem is achieved in that in a downhole motor containing a housing with a chamber for pumping the working fluid mounted in the cavity of the housing on the bearings of the rotor, according to the invention, a cavity is made inside the rotor divided by a partition into the upper and lower cavities, the lower rotor cavity is in communication with the housing cavity at using radial holes made in the wall in the lower part of the rotor, and the upper cavity is communicated with radial holes made in the wall in the upper part of the rotor, with nozzles installed mi on the outer surface of the rotor and directed in opposite directions from each other, with the Central axis of the nozzles perpendicular to the Central axis of the radial holes and the axis of rotation of the rotor.

Figure 1 shows a downhole motor - a longitudinal section; figure 2 is a section aa in figure 1.

The downhole motor comprises a housing 1 with a chamber 2 for pumping the working fluid, in the inner cavity 3 of the housing 1 is mounted on the bearings 4 of the rotor 5. Inside the rotor 5 there is a cavity divided by a partition 6 into the upper cavity 7 and the lower cavity 8. The lower cavity 8 of the rotor 5 is communicated with the internal cavity 3 of the housing 1 by means of radial holes 9 made in the wall in the lower part of the rotor 5, and the upper cavity 7 is communicated by means of radial holes 10 made in the wall in the upper part of the rotor 5, with nozzles 11 (see Fig. 2 ) installed on the outer surface of the rotor 5. Nozzles 11 are directed in opposite directions from each other, and the Central axis of the nozzles 11 are perpendicular to the Central axes of the radial holes 10 and the axis of rotation of the rotor 5.

Downhole motor works as follows.

The working fluid from the chamber 2 enters the upper cavity 7 of the rotor 5, the partition 6 prevents the working fluid from entering the lower cavity 8, and it goes through the radial holes 10 into the nozzle 11, where the acceleration of the movement of the working fluid. The jet of the working fluid leaves at high speed from the nozzles 11 into the inner cavity 3 of the housing 1, and a reactive force is generated which creates a torque on the rotor 5. Then, the working fluid from the inner cavity 3 is directed through the radial holes 9 into the lower cavity 8 of the rotor 5 and then goes to a rock cutting tool (not shown).

Thus, the rotor uses only the reactive force of the outgoing jet of the working fluid for its rotation; the casing does not participate in the force interaction. Therefore, the proposed downhole motor does not have a reactive moment and does not require fixing the housing during operation.

Claims (1)

The downhole motor, comprising a housing with a chamber for pumping the working fluid, mounted in the cavity of the housing on bearings of the rotor, characterized in that a cavity is made inside the rotor divided by a partition into the upper and lower cavities, the lower cavity of the rotor is in communication with the cavity of the housing using radial holes made in the wall in the lower part of the rotor, and the upper cavity is communicated using radial holes made in the wall in the upper part of the rotor, with nozzles mounted on the outer surface of the rotor and ennymi in opposite directions from each other, the central axes of the nozzles are perpendicular to the central axes of the radial holes and the rotor rotational axis.

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