A leak-proof sealing plunger, a pump and a slow pumping system

Abstract

This invention discloses a leak-free sealing plunger, an anti-sticking oil pump, and a slow-pump oil production system. The system includes an upper valve cover (101), a plunger tube (103), a lower valve cover (106), and a lower valve seat cap (108) that are sequentially and fixedly connected from top to bottom. It also includes an upper valve ball seat (102) located inside the upper valve cover (101) and a lower valve ball seat (107) located inside the lower valve cover (106). Multiple copper cup support sleeves (104) are fixedly fitted onto the outer wall of the plunger tube (103) from top to bottom. Each copper cup support sleeve (104) is fixedly equipped with a copper cup (105), and the upper part of the copper cup (105) has multiple slits (1052). This invention employs a copper-sealed plunger structure, and the copper sealing element is equipped with a scraping blade to prevent pump sticking, thereby minimizing oil pump leakage, improving oil production efficiency, reducing well repair frequency, and significantly reducing well repair costs.

Description

Technical Field

[0001] This invention relates to an oil pump and an oil production system, and more particularly to a leak-free sealing plunger and an anti-jamming oil pump and a slow-pump oil production system. Background Technology

[0002] In current oilfield development, standard oil pump plungers and barrels are clearance-fitted, resulting in a certain amount of leakage. During production, the plunger reciprocates thousands of times daily within the barrel, continuously lifting oil to the surface. Some sand and mud from the formation enter the space between the pump barrel and plunger with the oil flow. While the pump has a small clearance, low leakage, and high efficiency, it is prone to jamming, requiring pump lift-and-workout. Before the pump is completely jammed, the relative movement between the plunger and barrel causes scratches on the plunger surface and the inner surface of the barrel. Extensive scratching reduces pump efficiency and can even lead to complete pump failure. Frequent pump failures inevitably increase the workload and cost of well workover operations, severely impacting normal production. Simultaneously, the clearance between the barrel and plunger causes leakage, affecting crude oil production.

[0003] As oilfield development enters its mid-to-late stages, the crude oil content in the formation decreases, leading to a decline in the fluid supply from the wells. This increases the likelihood of gas lock in the pumping unit, and the increased frequency of dry friction between the plunger and the pump barrel exacerbates wear on both, causing the pump to fail rapidly. Simultaneously, increased dry friction at the wellhead seal can also lead to frequent pump failures. One solution is to reduce the pumping unit's stroke rate to match the fluid supply from the formation, significantly reducing the likelihood of gas lock and the frequency of dry friction between the plunger and the pump barrel. However, the leakage rate of current standard pumping units limits the stroke rate; excessively low stroke rates result in leakage exceeding the pumped output, leading to a significant reduction in pump efficiency.

[0004] In order to increase crude oil production in the mid-to-late stages of oilfield production and ensure normal production needs, it is urgent to develop a leak-free oil pump plunger, an anti-jamming oil pump, and a slow-pump oil production system to alleviate the aforementioned problems through slow-pump oil production technology. Summary of the Invention

[0005] To address the shortcomings of the existing technology, the present invention aims to provide a leak-free sealing plunger, an anti-sticking oil pump, and a slow-pump oil production system. The system employs a copper sealing plunger structure, where the copper sealing element is sleeved with the inner wall of the pump barrel to achieve a seal. Sand particles will not enter the space between the pump barrel and the plunger with the oil flow. Simultaneously, the copper sealing element is equipped with a scraping blade to prevent pump sticking, thus minimizing pump leakage, thereby improving oil production efficiency, reducing well workover frequency, and significantly lowering well workover costs.

[0006] The first aspect of the present invention is to provide a leak-free sealing plunger, comprising an upper valve cover, a plunger tube, a lower valve cover, and a lower valve seat cap that are sequentially and fixedly connected from top to bottom, as well as an upper valve ball seat and a lower valve ball seat disposed inside the upper valve cover. A plurality of copper cup support sleeves are fixedly fitted from top to bottom on the outer wall of the plunger tube. Each copper cup support sleeve is fixedly provided with a copper cup. The copper cup is bowl-shaped with a wider top and a narrower bottom. Its lower part is fixedly connected to the copper cup support sleeve, and its upper part is divided into several equal parts by a plurality of evenly arranged slits. The slits of adjacent copper cups on the plunger tube are staggered.

[0007] As a further optimization of the technical solution of the present invention, the upper valve cover, plunger tube, lower valve cover and lower valve seat cap are respectively sealed and fixedly connected by tapered pipe threads.

[0008] As a further optimization of the technical solution of the present invention, the copper cup support sleeve and the plunger tube body are fixedly connected by an interference fit.

[0009] As a further optimization of the technical solution of the present invention, the copper cup and the copper cup support sleeve are sealed and fixedly connected by tapered pipe thread, or fixedly connected by interference fit.

[0010] As a further optimization of the technical solution of the present invention, the top of the copper cup is provided with a sharp-angled scraping blade, which effectively scrapes away sand and dirt adhering to the inner wall of the pump barrel during the reciprocating motion of the plunger and the pump barrel.

[0011] As a further optimization of the technical solution of the present invention, the number of slits on the upper part of the copper cup is 4, 6 or 8. By dividing the upper part of the copper cup equally by slits, the compressive stress can be effectively eliminated, thereby greatly enhancing the sealing between the plunger and the pump barrel.

[0012] As a further optimization of the technical solution of the present invention, the number of copper cups provided on the plunger tube is not less than three, so as to further enhance the sealing between the plunger and the pump barrel.

[0013] As a further optimization of the technical solution of the present invention, the adjacent copper cups on the plunger tube are arranged in a head-to-tail manner or in a partially overlapping manner.

[0014] Another aspect of the present invention is to provide an anti-jamming oil pump, including a pump barrel, wherein a sealing connection assembly is provided at the upper end of the pump barrel, and a sealing plunger is sleeved inside the assembly, wherein the sealing plunger is a leak-free sealing plunger as described in any of the preceding claims.

[0015] Another aspect of the present invention is to provide a slow-pumping oil production system, including a pumping unit, a motor, a gearbox, a wellhead, a tubing string, and a sucker rod string, wherein a pulley reducer is provided between the motor and the gearbox; the lower end of the tubing string is sealed and fixedly connected to the upper end of the pumping unit, and the pumping unit is the aforementioned anti-jamming pumping unit.

[0016] In the above technical solution, the sealing connection between the copper cup and the pump barrel can eliminate the leakage of the oil pump to the greatest extent. Therefore, in the mid-to-late stage of oil wells, when the production rate is the same, the pump diameter of the anti-sticking oil pump can be increased. A pulley reducer is installed between the motor and the gearbox to significantly reduce the number of pumping unit strokes. This reduces the probability of oil pump air lock and significantly improves pump efficiency, thereby improving oil production efficiency and reducing the number of well workovers.

[0017] In summary, compared with the prior art, the leak-free sealing plunger, anti-jamming oil pump, and slow-pump oil production system of the present invention have the following technical advantages:

[0018] (1) No leakage, high pump efficiency, which can effectively improve oil production efficiency;

[0019] (2) Copper-plated bowls are resistant to high temperatures and have good wear resistance, while also preventing uneven wear;

[0020] (3) The copper cup does not wear down the pump barrel. When it is damaged, it can be replaced simply by lifting the sucker rod string. The maintenance is simple.

[0021] (4) Slow extraction can effectively reduce the wear and tear of the oil pump and the probability of pump jamming, and significantly reduce the cost of well repair. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the leak-free sealing plunger, the anti-jamming oil pump, and the oil production device according to an embodiment of the present invention;

[0023] Figure 2 This is a cross-sectional view of the leak-free sealing plunger in an embodiment of the present invention;

[0024] Figure 3 This is an enlarged view of the structure of multiple copper cups on the plunger in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of a single copper bowl in an embodiment of the present invention;

[0026] Figure 5 This is an axonometric view of multiple copper bowls in an embodiment of the present invention;

[0027] Figure 6 This is a cross-sectional view of the anti-jamming oil pump in an embodiment of the present invention;

[0028] In the diagram: 1-Pumping unit, 2-Motor, 3-Pulley reducer, 4-Gearbox, 5-Keeper tree, 6-Well, 7-Tubing string, 8-Sucker rod string, 9-Anti-jamming pump, 10-Sealing plunger, 91-Pump barrel, 101-Upper valve cover, 102-Upper valve ball seat, 103-Plunger tube, 104-Copper cup support sleeve, 105-Copper cup, 106-Lower valve cover, 107-Lower valve ball seat, 108-Lower valve seat cap, 1051-Scraper blade, 1052-Slot cutter. Detailed Implementation

[0029] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments of this invention. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0030] Figure 1-6 The present invention illustrates an embodiment of the leak-free sealing plunger, anti-jamming oil pump, and slow-pump oil production system.

[0031] like Figure 2-5 As shown, a leak-free sealing plunger includes an upper valve cover 101, a plunger tube 103, a lower valve cover 106, and a lower valve seat cap 108, which are sealed and fixedly connected from top to bottom. An upper valve ball seat 102 is located inside the upper valve cover 101, and a lower valve ball seat 107 is located inside the lower valve cover 106. Three copper cup support sleeves 104 are fixedly fitted onto the outer wall of the plunger tube 103 from top to bottom. Each copper cup support sleeve 104 has a fixed copper cup 105. The copper cup 105 is bowl-shaped, wider at the top and narrower at the bottom. Its lower part is fixedly connected to the copper cup support sleeve 104, and its upper part is divided into six equal parts by six evenly arranged slits 1052. The slits 1052 of adjacent copper cups 105 on the plunger tube 103 are staggered.

[0032] In this embodiment, the upper valve cover 101, the plunger tube 103, the lower valve cover 106, and the lower valve seat cap 108 are respectively sealed and fixedly connected by tapered pipe threads.

[0033] In this embodiment, the copper cup support sleeve 104 and the plunger tube 103 are fixedly connected by an interference fit.

[0034] In this embodiment, the copper cup 105 and the copper cup support sleeve 104 are sealed and fixedly connected by a tapered pipe thread.

[0035] In this embodiment, the top of the copper bowl 105 is provided with a sharp-angled scraping blade 1051.

[0036] In this embodiment, the adjacent copper cups 105 on the plunger tube 103 are arranged in a head-to-tail manner.

[0037] like Figure 6 As shown, an anti-jamming oil pump includes a pump barrel 91. The upper end of the pump barrel 91 is provided with a sealing connection assembly, and a sealing plunger 10 is sleeved inside it. The sealing plunger 10 is the aforementioned leak-free sealing plunger.

[0038] like Figure 1 As shown, a slow-pump oil production system includes a pumping unit 1, a motor 2, a gearbox 4, a treehouse 5, a well 6, a tubing string 7, and a sucker rod string 8. A pulley reducer 3 is provided between the motor 2 and the gearbox 4. The lower end of the tubing string 7 is sealed and fixedly connected to the upper end of the pumping pump 9, which is the aforementioned anti-jamming pumping pump.

[0039] The leak-free sealing plunger, anti-jamming pump, and slow-pump oil production system of the present invention are suitable for oil production in the mid-to-late stages of oilfield development, when the crude oil content in the formation decreases and the fluid supply from the well decreases. By utilizing the sealing sleeve between the copper cup 105 and the pump barrel 91, the leakage of the pump 9 can be eliminated to the greatest extent. Therefore, by increasing the pump diameter of the anti-jamming pump 9 and installing a pulley reducer 3 between the motor 2 and the gearbox 4, the stroke rate of the pumping unit 1 can be significantly reduced, which reduces the probability of air lock in the pump 9 and significantly improves the pump efficiency, thereby improving oil production efficiency, reducing the number of well workovers, and reducing well workover costs.

[0040] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "inner side," "outer side," "upper end," "lower end," "one side," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, improvements, etc., made by any person skilled in the art without departing from the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A leak-free sealing plunger, comprising an upper valve cover (101), a plunger tube (103), a lower valve cover (106), and a lower valve seat cap (108) sequentially and fixedly connected from top to bottom, and an upper valve ball seat (102) disposed inside the upper valve cover (101) and a lower valve ball seat (107) disposed inside the lower valve cover (106), characterized in that: Multiple copper cup support sleeves (104) are fixedly fitted on the outer wall of the plunger tube (103) from top to bottom. Each copper cup support sleeve (104) is fixedly provided with a copper cup (105). The copper cup (105) is bowl-shaped with a thicker top and a thinner bottom. Its lower part is fixedly connected to the copper cup support sleeve (104), and its upper part is divided into several equal parts by a number of evenly arranged slits (1052). The slits (1052) of adjacent copper cups (105) on the plunger tube (103) are staggered. The top of the copper cup (105) is provided with a scrubbing blade (1051) with an acute angle. The upper valve cover (101), plunger tube (103), lower valve cover (106) and lower valve seat cap (108) are respectively sealed and fixedly connected by tapered pipe threads.

2. The leak-free sealing plunger according to claim 1, characterized in that: The copper cup support sleeve (104) and the plunger tube (103) are fixedly connected by an interference fit.

3. The leak-free sealing plunger according to claim 1, characterized in that: The copper cup (105) and the copper cup support sleeve (104) are sealed and fixedly connected by tapered pipe thread, or fixedly connected by interference fit.

4. The leak-free sealing plunger according to claim 1, characterized in that: The number of slits (1052) on the upper part of the copper bowl (105) is 4, 6 or 8.

5. The leak-free sealing plunger according to claim 1, characterized in that: The number of copper cups (105) provided on the plunger tube (103) shall not be less than three.

6. The leak-free sealing plunger according to claim 1, characterized in that: The copper cups (105) on the plunger tube (103) are arranged in a head-to-tail manner or in a partially overlapping manner.

7. An anti-jamming oil pump, comprising a pump barrel (91), wherein the upper end of the pump barrel (91) is provided with a sealing connection assembly, characterized in that: The pump barrel (91) is fitted with a sealing plunger (10), which is the leak-free sealing plunger as described in any one of claims 1-6.

8. A slow-pump oil production system, comprising a pumping unit (1), a motor (2), a gearbox (4), a Christmas tree (5), a production well (6), a tubing string (7), and a sucker rod string (8), characterized in that: A pulley reducer (3) is provided between the motor (2) and the gearbox (4); the lower end of the oil pipe column (7) is sealed and fixedly connected to the upper end of the oil pump (9), and the oil pump (9) is the anti-jamming oil pump as described in claim 7.

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