Texture structure anti-drag rubber screw pump

Abstract

The invention discloses a texture structure anti-drag rubber screw pump which comprises a rotor and a stator, a rubber lining is arranged in the stator, a through hole is formed in the rubber lining in the axial direction of the stator, and the hole wall of the through hole is formed by connecting a plurality of small planes distributed circumferentially. According to the invention, the small plane structure is arranged on the inner surface of the rubber lining, lubricating oil can be stored at the edge of the small plane, and due to the existence of the small plane, the rotor and the stator are not in full contact, and the actual contact area of the stator and the rotor is small, so that the friction force is reduced, and the wear resistance of the stator is improved.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas production technology, and particularly relates to a textured drag-reducing rubber screw pump. Background Technology

[0002] Screw pumps are widely used in the oil extraction field, and are particularly suitable for the extraction of high-viscosity, high-sand-content crude oil. They are widely used in deviated wells, horizontal wells, swamp areas and offshore platform oil production operations, and have the characteristics of low cost and low energy consumption.

[0003] A screw pump mainly consists of a metal rotor and a stator (a metal tube lined with rubber). During operation, the stator rubber is subjected to impact and friction from the metal rotor. In the initial stage of operation, because crude oil has not yet filled the entire stator cavity, the oil-producing screw pump is in a dry friction state, inevitably resulting in dry friction between the stator and rotor. Simultaneously, in oil wells with high gas content, insufficient crude oil lubrication also leads to dry friction, resulting in significant rubber wear. During the stable operation phase of the screw pump, the stator and rotor are interference-fitted, resulting in a thin or even nonexistent lubrication film between them. This is especially true in oil wells with high water content, where insufficient lubrication of the stator and rotor also leads to high friction and severe wear.

[0004] Therefore, dry friction should be avoided as much as possible during the startup and operation of screw pumps. At the same time, enhancing the lubrication between the stator and rotor is of great significance for reducing frictional torque, reducing wear, and improving the service life of the pump. Summary of the Invention

[0005] To overcome the shortcomings of the existing technology, the present invention aims to avoid dry friction during the startup of a screw pump. To achieve this objective, the present invention provides the following technical solution: A textured drag-reducing rubber screw pump includes a rotor and a stator. The stator has a rubber liner inside, and a through hole is provided in the rubber liner along the axial direction of the stator. The wall of the through hole is formed by a number of circumferentially distributed small planes connected to each other.

[0006] Furthermore, the small plane is a polygon.

[0007] Furthermore, all sides of the small plane have the same length.

[0008] Furthermore, the length of one side of the small plane is 1-6 mm.

[0009] Furthermore, the edge of the small plane is recessed, and the depth of the recess is 0.1-0.5mm.

[0010] Furthermore, the small planes within the same rubber liner have the same shape.

[0011] Furthermore, the inner surface of the rubber liner is silanized.

[0012] The technical effects and advantages of this invention are as follows: In this invention, a small planar structure is provided on the inner surface of the rubber liner. Lubricating oil can be stored at the edge of the small planar structure. Furthermore, due to the presence of the small planar structure, the rotor and stator are not in full contact, and the actual contact area between the stator and rotor is small, thereby reducing friction and improving the wear resistance of the stator.

[0013] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description and the drawings. Attached Figure Description

[0014] Figure 1 A schematic diagram of a small planar structure inside a rubber liner provided by the present invention; Figure 2 This is a schematic diagram of another small planar structure inside a rubber liner provided by the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Furthermore, in this invention, the terms "first," "second," and other similar words are not intended to imply any order, quantity, or importance, but are merely used to distinguish different elements, and the terms "upper," "lower," "left," "right," and other similar words are merely positional relationships in the accompanying drawings.

[0017] In this invention, the stator liner of the screw pump is made of rubber, and the inner surface of the rubber cavity is provided with repeatedly arranged small planes. Due to the presence of the concave edges of the small planes, the contact between the rotor and the stator is not sufficient, thereby reducing the actual contact area between the stator and the rotor, and thus reducing the friction between the stator and the rotor. Specific embodiments will be used to illustrate this further.

[0018] This invention provides a textured drag-reducing rubber screw pump, the screw pump comprising: a rotor and a stator, the stator having an internal rubber liner, the rubber liner being hollow, and the inner surface of the rubber liner being composed of a plurality of circumferentially distributed small planes connected to each other.

[0019] Specifically: like Figure 1 As shown, in one embodiment of the present invention, the small plane is a regular hexagon with a single side length of 3-4 mm; the small planes are arranged in a repeating pattern, covering the inner surface of the rubber cavity, with adjacent small planes sharing a single side, and the depth of the concave edge of the small plane is 0.1 mm.

[0020] The small facet is treated with silanization by preparing a mixture of methyltrichlorosilane and n-hexane at a volume ratio of 1%. The mixture is then coated onto the inner surface of the rubber cavity, left to stand for 2 hours, and dried at 75°C for 3 hours. This process gives the small facet boundary an oil adhesion effect, further improving the lubrication performance of the rubber stator.

[0021] Compared with traditional screw pumps without repeating small planes, under the same operating conditions, the screw pump in this embodiment has a 21% lower peak starting power, an 11% lower average power during operation, and a 1.1 times longer wear life of the rubber stator.

[0022] like Figure 2 As shown, in one embodiment of the present invention, the small plane is a regular quadrilateral, and the length of a single side of the small plane polygon is 2-4 mm; the small planes are arranged in a repeating structure, covering the inner surface of the rubber cavity, adjacent small planes share a side, and the depth of the concave edge of the small plane is 0.3 mm; The small facet is treated with silanization by preparing a mixture of methyltrichlorosilane and n-hexane in a volume ratio of 1.5%. The mixture is then coated onto the inner surface of the rubber cavity, left to stand for 3 hours, and dried at 60°C for 4 hours. This process gives the small facet boundary an oil adhesion effect, further improving the lubrication performance of the rubber stator.

[0023] Compared with traditional screw pumps without repeating small planes, under the same operating conditions, the screw pump in this embodiment has a 23% lower peak starting power, a 14% lower average power during operation, and a 1.5 times longer wear life for the rubber stator.

[0024] In one embodiment of the present invention, the small plane is a regular hexagon; the length of a single side of the small plane polygon is 3-5mm; the small planes are arranged in a repeating structure, covering the inner surface of the rubber cavity, adjacent small planes share a side, and the depth of the concave edge of the small plane is 0.5mm; The small facet is treated with silanization, using a mixture of trimethylchlorosilane and n-hexane at a volume ratio of 2%. The mixture is then coated onto the inner surface of the rubber cavity, left to stand for 4 hours, and dried at 60°C for 3 hours. This process gives the small facet boundary an oil adhesion effect, further improving the lubrication performance of the rubber stator.

[0025] Compared with traditional screw pumps without repeating small planes, under the same operating conditions, the screw pump in this embodiment has a 25% lower peak starting power, a 16% lower average power during operation, and a 1.8 times longer wear life of the rubber stator.

[0026] In one embodiment of the present invention, the small plane is triangular; the length of a single side of the small plane polygon is 2-4 mm; the small planes are arranged in a repeating structure, covering the inner surface of the rubber cavity, adjacent small planes share a side, and the depth of the concave edge of the small plane is 0.3 mm; The small facet is treated with silanization, using a mixture of trimethylchlorosilane and n-hexane at a volume ratio of 3%. The mixture is then coated onto the inner surface of the rubber cavity, left to stand for 3 hours, and dried at 55°C for 5 hours. This process gives the small facet boundary an oil adhesion effect, further improving the lubrication performance of the rubber stator.

[0027] Compared with traditional screw pumps without repeating small planes, under the same operating conditions, the screw pump in this embodiment has a 22% lower peak starting power, a 15% lower average power during operation, and a 1.7 times longer wear life of the rubber stator.

[0028] Small planes are set on the inner surface of the rubber cavity. A corresponding small plane structure can be formed by processing an imprint on the surface of the metal core mold used in the molding of the rubber stator of the screw pump. During the injection molding process of the rubber stator, the metal core mold passes through the center of the pump barrel, and the rubber is injected into the annular space between the core mold and the pump barrel. After the rubber stator is formed, a repeating small plane structure is formed on the inner surface of the rubber cavity.

[0029] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A textured, drag-reducing rubber screw pump, characterized in that, The screw pump includes a rotor and a stator. The stator has a rubber liner inside, and the rubber liner has a through hole along the axial direction of the stator. The wall of the through hole is formed by a number of circumferentially distributed small planes connected to each other.

2. The textured drag-reducing rubber screw pump according to claim 1, characterized in that, The small plane is a polygon.

3. The textured drag-reducing rubber screw pump according to claim 2, characterized in that, The sides of the small plane are all the same length.

4. The textured drag-reducing rubber screw pump according to claim 3, characterized in that, The length of one side of the small plane is 1-6mm.

5. The textured drag-reducing rubber screw pump according to claim 1, characterized in that, The small plane has a recessed edge with a depth of 0.1-0.5 mm.

6. The textured drag-reducing rubber screw pump according to claim 1, characterized in that, The small planes within the same rubber liner have the same shape.

7. A textured drag-reducing rubber screw pump according to any one of claims 1-6, characterized in that, The inner surface of the rubber liner is silanized.

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