Piston of hydraulic double-acting rodless oil extraction pump

Abstract

The utility model discloses a hydraulic double-acting rodless oil extraction pump piston. The piston at least comprises a piston body; the two ends of the piston body are provided with spring seals; a main sealing device is arranged in the middle of the piston body; the main sealing device is arranged in a sealing ring groove of the piston body; the main sealing device comprises a split type metal sealing ring, and the split type metal sealing ring is formed by annularly arranging two or three arc-shaped metal pieces with the same radian. A U-shaped groove is inwards formed in the inner surface of each arc-shaped metal piece; an O-shaped sealing ring is arranged in the U-shaped groove; and a plurality of guide sealing rings are arranged on the piston body between the spring seal and the main sealing device at intervals. The piston body is provided with the opening type compensation metal sealing ring, and outward tension is provided for the opening type compensation metal sealing ring through the storage capacity of the O-shaped pre-pressing ring, so that a good sealing state is kept between the piston and a pump cylinder; a plurality of macromolecular guide sealing elements of the piston play an auxiliary guide role; and a sand scraping ring is additionally arranged for sand scraping and auxiliary sealing.

Description

Technical Field

[0001] The utility model relates to a hydraulic double-acting rodless oil pump piston. Background Art

[0002] Chinese patent application number 200820110494.9, invention name: Hydraulic double-acting rodless pump; application number 201410675560.7, invention name: Hydraulic double-acting rodless oil pump, both disclose hydraulic double-acting rodless oil pumps; in actual use, during the manufacturing and actual operation of the hydraulic rodless oil pump barrel, the piston surface wears greatly, the sealing is poor, and the piston is not well centered in the pump barrel, which greatly reduces the operating cycle, increases maintenance work, and increases oil production costs. Utility Model Content

[0003] In order to overcome the above-mentioned defects, the purpose of the present utility model is to provide a hydraulic double-acting rodless oil pump piston.

[0004] In order to achieve the above-mentioned purpose, the hydraulic double-acting rodless oil pump piston of the utility model comprises at least a piston body; a pan seal is provided at both ends of the piston body;

[0005] A main sealing device is provided in the middle of the piston body; the main sealing device is provided in the sealing ring groove of the piston body; the main sealing device comprises: a split metal sealing ring, the split metal sealing ring being arranged in a ring shape by two or three arc-shaped metal pieces of the same curvature; the inner surface of each arc-shaped metal piece is provided inwardly with a U-shaped groove; an O-ring is provided in the U-shaped groove;

[0006] A plurality of guide sealing rings are arranged at intervals on the piston body between the pan seal and the main sealing device.

[0007] Furthermore, a shaft head centralizer is connected to one end of the piston, and a pump shaft connecting bolt is connected to one end of the shaft head centralizer.

[0008] Furthermore, a first hydraulic compensating scraper ring is provided between the shaft head centralizer and the pump shaft connecting bolt.

[0009] Furthermore, a second hydraulic compensating scraper ring is provided at the other end of the piston.

[0010] Furthermore, a piston center automatic adjuster is provided between the shaft head centralizer and the piston.

[0011] Furthermore, the piston center automatic adjuster includes: a cylindrical articulated seat connected to the end of the piston; a hinge hole is provided at the end of the cylindrical articulated seat far from the piston; the diameter of the articulated hole is smaller than the inner diameter of the bottom of the cylindrical articulated seat; a hinge head is provided in the cylindrical articulated seat, the diameter of which is larger than the articulated hole and smaller than the diameter of the bottom of the cylindrical articulated seat; a hinge rod is provided on the side of the articulated head near the articulated hole, and the diameter of the articulated rod is smaller than the diameter of the articulated hole; the end of the articulated rod located outside the articulated hole is connected to the shaft head straightener.

[0012] The utility model has the following advantages: an open compensating metal sealing ring (can also be an open polymer non-metallic material) is adopted on the piston body, and the storage capacity of the O-type pre-compression ring is provided to the open compensating metal sealing ring to provide outward tension, so that a good sealing state is maintained between the piston and the pump barrel; multiple polymer guide seals on the piston play an auxiliary guiding role; and a scraping ring is added to scrape sand and assist in sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural diagram of the present utility model.

[0014] Figure 2 Schematic diagram of the structure of the main sealing device.

[0015] Figure 3 for Figure 2 Schematic cross-sectional view of .

[0016] Figure 4 for Figure 1 Exploded diagram of the automatic center adjuster for the middle piston. DETAILED DESCRIPTION

[0017] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0018] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0019] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0020] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0021] Example 1

[0022] like Figures 1 to 3 As shown, the piston of the utility model comprises at least: a piston body 8, which is made of a high-temperature-resistant, corrosion-resistant and wear-resistant metal material and is an important component of the hydraulic double-acting rodless oil pump, serving as a gap seal and a piston travel guide; a pan seal 7 is provided at both ends of the piston body, which is a non-metallic polymer flexible sealing material, so that the pump barrel and the piston are reliably sealed;

[0023] A main sealing device is provided in the middle of the piston body, and two main sealing devices are provided in the figure; the main sealing device is provided in the sealing ring groove of the piston body; the main sealing device comprises: a split metal sealing ring, which is arranged in a ring by two semicircular arc-shaped metal parts 11, and a gap of 0.5-1.5 mm is provided between two adjacent arc-shaped metal parts; a U-shaped groove is provided inwardly on the inner surface of each arc-shaped metal part; an O-ring 10 is provided in the U-shaped groove, and the radius of the O-ring 10 is equivalent to the radius of the U-shaped groove; the O-ring should be a high-temperature and corrosion-resistant O-ring; when the piston is installed in the pump body, the O-ring is flattened in the sealing ring groove to generate pre-pressure, which plays an energy storage role. The external tension of the pre-pressure is transmitted to the split metal sealing ring to compensate for the external tension, so that the piston and the pump barrel are more tightly sealed. The stored energy of the O-ring continuously supplies compensation for the external tension of the metal sealing ring, maintains a good sealing state, extends the operating cycle, and improves the sealing reliability.

[0024] A plurality of guide sealing rings 9 are arranged at intervals on the piston body between the pan seal and the main sealing device.

[0025] Example 2

[0026] As a further improvement to the above embodiment, one end of the piston is equipped with a pump shaft connecting bolt 1, a polymer hydraulic compensating sand scraper 2, and a shaft head centralizer. The outer diameter of the polymer hydraulic compensating sand scraper 2 is free of gaps with the pump barrel, keeping sand in the oil well fluid out of the piston assembly, keeping it relatively clean. This reduces wear on the piston and pump barrel, and improves the downhole unit's operating cycle. The shaft head centralizer is used for initial shaft alignment.

[0027] Example 3

[0028] On the basis of the above embodiment, a piston center automatic adjuster is provided between the centralizer and the piston; the piston can automatically adjust the piston and the pump barrel to be concentric, thereby reducing the mechanical wear of the piston and the pump barrel;

[0029] The piston center automatic adjuster is connected to the cylindrical hinge seat 6 at the end of the piston; a hinge hole is provided at the end of the cylindrical hinge seat far from the piston; the diameter of the hinge hole is smaller than the inner diameter of the bottom of the cylindrical hinge seat; a hinge head 5 is provided in the cylindrical hinge seat, the diameter of which is larger than the hinge hole and smaller than the diameter of the bottom of the cylindrical hinge seat; a hinge rod is provided on the side of the hinge head near the hinge hole, and the diameter of the hinge rod is smaller than the diameter of the hinge hole; the end of the hinge rod located outside the hinge hole is connected to the shaft head straightener.

[0030] An adjusting nut 4 is provided on the hinged rod for adjusting and fixing the piston center automatic adjuster.

[0031] The present invention has been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above-described embodiments. Various modifications may be made within the scope of knowledge of those skilled in the art without departing from the spirit of the present invention. Many other changes and modifications that do not depart from the spirit and scope of the present invention should be considered within the scope of protection of the present invention.

[0032] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0033] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A hydraulic double-acting rodless oil pump piston, characterized in that: The piston at least comprises a piston body; pan seals are provided at both ends of the piston body; A main sealing device is provided in the middle of the piston body; the main sealing device is provided in the sealing ring groove of the piston body; the main sealing device comprises: a split metal sealing ring, the split metal sealing ring being arranged in a ring shape by two or three arc-shaped metal pieces of the same curvature; the inner surface of each arc-shaped metal piece is provided inwardly with a U-shaped groove; an O-ring is provided in the U-shaped groove; A plurality of guide sealing rings are arranged at intervals on the piston body between the pan seal and the main sealing device.

2. The hydraulic double-acting rodless oil pump piston according to claim 1, characterized in that: One end of the piston is connected to a shaft head centralizer, and one end of the shaft head centralizer is connected to a pump shaft connecting bolt.

3. The hydraulic double-acting rodless oil pump piston according to claim 2, characterized in that: A first hydraulic compensating scraper ring is provided between the shaft head centralizer and the pump shaft connecting bolt.

4. The hydraulic double-acting rodless oil pump piston according to claim 1, characterized in that: A second hydraulic compensating scraper ring is provided at the other end of the piston.

5. The hydraulic double-acting rodless oil pump piston according to claim 1, characterized in that: A piston center automatic adjuster is provided between the shaft head centralizer and the piston.

6. The hydraulic double-acting rodless oil pump piston according to claim 5, characterized in that: The piston center automatic adjuster includes: a cylindrical hinge seat connected to the end of the piston; a hinge hole is provided at the end of the cylindrical hinge seat far from the piston; the diameter of the hinge hole is smaller than the inner diameter of the bottom of the cylindrical hinge seat; a hinge head is provided in the cylindrical hinge seat, the diameter of which is larger than the hinge hole and smaller than the diameter of the bottom of the cylindrical hinge seat; a hinge rod is provided on the side of the hinge head near the hinge hole, the diameter of the hinge rod is smaller than the diameter of the hinge hole; the end of the hinge rod located outside the hinge hole is connected to the shaft head straightener.

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