Anti-rotation coupling

Abstract

An anti-rotation coupling relates to the field of oil pipes. The anti-rotation coupling comprises a nut, a tension ring and a coupling. The coupling is used to connect the oil pipes. The two ends of the coupling are locked and fixed by the nut and the tension ring. The coupling has a simple structure. After all the oil pipes in the well are connected by the coupling, the oil pipes can be regarded as a whole without anchoring, so that the oil pipes can be naturally vertical without anchoring bending, reduce eccentric wear of the oil pipes, and achieve the purpose of extending the pump inspection cycle.

Description

Technical Field

[0001] The invention relates to the field of downhole oil pipes, and in particular to an anti-rotation coupling. Background Art

[0002] The rotor of the screw pump keeps rotating during the oil production process. In order to offset the reverse torque generated by its rotation and avoid disengagement, the current practice is to install a tubing anchor under the pump. However, this tubing anchoring method has some disadvantages. For example, when using a hydraulic tubing anchor, after the tubing string is lowered into the well, a hydraulic power device needs to be installed to apply pressure to the hydraulic tubing anchor to fix the tubing anchor, which is costly. When the tubing string is fixed with a slideway tubing anchor, the tubing string will be forced to bend and deform, damaging the tubing, which is not ideal. Therefore, various screw pump tubing anchoring devices have been introduced, but most of them are complex structures with many parts, easy to wear, and unsafe to use. Summary of the invention

[0003] In view of the deficiencies in the prior art, an object of the present invention is to provide an anti-transfer coupling.

[0004] The technical solution adopted by the invention is: an anti-rotation coupling, the technical key points of which are: comprising a nut, a tensioning ring and a coupling, the nut, the tensioning ring and the coupling are respectively sleeved on the outer wall of the oil pipe, the coupling is threadedly connected to the oil pipe, the tensioning ring bites tightly on the surface of the oil pipe and one end of the tensioning ring is threadedly connected to the nut, and the other end forms a clearance fit structure with the coupling, so that the coupling is locked circumferentially on the oil pipe.

[0005] In the above scheme, the tensioning ring is provided with an inclined surface, vertical teeth and an external threaded connection end. The tensioning ring bites the surface of the oil pipe by the vertical teeth. The external threaded connection end of the tensioning ring is screwed with the internal thread of the nut. When the nut is rotated, the inclined surface of the tensioning ring shrinks inward under the action of the inclined surface of the coupling to form a clearance fit structure with the coupling.

[0006] The beneficial effects of the present invention are as follows: the anti-rotation coupling comprises a nut, a tensioning ring and a coupling, the coupling is used to connect the oil pipe, the two ends of the coupling are locked and fixed by the nut and the tensioning ring, the structure is simple, after all the oil pipes in the well are connected by the coupling, the oil pipes can be regarded as a whole, no anchoring is required, the oil pipes can be naturally vertical, there is no anchoring bending, the eccentric wear of the oil pipe is reduced, and the purpose of extending the pump inspection cycle is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0008] Figure 1It is a schematic diagram of the structure of the anti-rotation coupling in an embodiment of the present invention;

[0009] Figure 2 is a cross-sectional view of a tension ring in an embodiment of the present invention;

[0010] Figure 3 A top view of a tension ring in an embodiment of the present invention;

[0011] The serial numbers in the figure are explained as follows: 1 nut, 2 tension ring, 21 inclined surface, 22 vertical tooth, 23 external thread connection end, 3 coupling, 4 oil pipe. DETAILED DESCRIPTION

[0012] To make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the following is a brief description of the present invention in conjunction with the attached Figure 1 to Figure 3 The present invention is further described in detail with reference to the accompanying drawings and specific embodiments.

[0013] The anti-rotation coupling used in this embodiment includes a nut 1 with an internal thread, a tensioning ring 2, and a coupling 3 with a tubing coupling thread buckle. The tensioning ring 2 includes an inclined surface 21, a vertical tooth 22, and an external thread connection end 23. The nut 1, the tensioning ring 2, and the coupling 3 are respectively sleeved on the outer wall of the tubing 4, and the tubing coupling thread buckle of the coupling 3 is screwed and fixed with the external thread of the tubing 4, thereby ensuring the connection and sealing between the coupling 3 and the tubing 4. The external thread connection end 23 of the tensioning ring 2 is screwed with the internal thread of the nut 1, the tensioning ring 2 is bitten with the tubing 4 by the vertical tooth 21, and the tensioning ring 2 is connected with the inclined surface of the coupling 3 by the clearance fit of the inclined surface 21. When the nut 1 is rotated, the tensioning ring 2 moves toward the coupling 3, and the inclined surface of the tensioning ring 2 shrinks inward under the action of the inclined surface of the coupling 3 to form a clearance fit structure with the coupling 3, so that the coupling 3 is circumferentially locked with the tubing. The tension ring 2 in this embodiment is responsible for preventing the oil pipe 4 and the coupling 3 from rotating and disengaging.

[0014] In this embodiment, the coupling 3 is used to connect the oil pipes in the whole well, and the coupling 3 is connected and sealed to the outside of the oil pipe 4 by the matching structure of the nut 1 and the tension ring 2, so that the oil pipe becomes a whole, and the natural verticality of the oil pipe can be achieved without anchoring.

[0015] The process of connecting the oil pipe using the anti-rotation coupling in this embodiment is as follows:

[0016] When connecting, first connect the external thread of the oil pipe 4 and the oil pipe coupling thread of the coupling 3, then screw the nut 1 and the tensioning ring 2 together, and after the connection, rotate the nut 1 to tighten the tensioning ring 2 and move it toward the end of the coupling 3 with the inclined surface. The inclined surface of the tensioning ring 2 shrinks inward under the action of the inclined surface of the coupling, and the coupling 3 and the oil pipe are circumferentially locked, completing the connection between the oil pipe 4 and the coupling 3.

[0017] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An anti-rotation coupling, characterized in that: It comprises a nut (1), a tensioning ring (2) and a coupling (3), wherein the nut (1), the tensioning ring (2) and the coupling (3) are respectively sleeved on the outer wall of an oil pipe (4), the coupling (3) is screwed to the oil pipe (4), the tensioning ring (2) is tightly attached to the surface of the oil pipe (4) and one end of the tensioning ring (2) is screwed to the nut (1), and the other end forms a clearance fit structure with the coupling (3), so that the coupling (3) is locked in the circumferential direction of the oil pipe (4); The tension ring (2) is provided with an inclined surface (21), vertical teeth (22) and an external thread connection end (23). The tension ring (2) is tightened on the surface of the oil pipe (4) by means of the vertical teeth (22). The external thread connection end (23) of the tension ring (2) is threadedly connected to the internal thread of the nut (1). When the nut (1) is rotated, the inclined surface of the tension ring (2) contracts inwardly under the action of the inclined surface of the coupling (3) to form a clearance fit structure with the coupling (3).

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