A combined downhole pump

Abstract

This invention relates to a combined downhole pump, comprising a multi-section pump assembly. Each pump assembly includes a stator and a rotor. A positioner connects each pump assembly section. The positioner includes a housing assembly and a sucker assembly, with both ends of the sucker assembly connected to the rotor. A casing is also provided between the outer side of a portion of the sucker assembly and the inner side of the housing assembly. A bearing assembly and a sealing assembly are respectively provided on the outer side of the casing. An oil passage ring is also provided on the outer side of the sucker assembly, with at least one oil passage hole. An adjuster is also provided at the end of the oil passage ring furthest from the casing. By providing the positioner, not only can the connection between each pump assembly section be achieved, but an adjuster is also provided in the housing assembly. The adjuster consists of a centralizing joint and a bearing ring. By providing a conical surface on the bearing ring, when the sucker rod connected to the centralizing joint swings, the guiding effect of the conical surface ensures that the centralizing joint and the bearing ring are coaxial, thereby ensuring that the sucker rod, centralizing joint, and bearing ring are coaxially arranged.

Description

Technical Field

[0001] This invention relates to the field of mechanical automation equipment, and more particularly to a combined downhole pump. Background Technology

[0002] Downhole screw pumps consist of a rotor and a stator, and are a type of positive displacement pump. The rotor is the only moving part of the pump, and it is lowered into the well using a sucker rod. Power from the surface is transmitted to the rotor via the sucker rod, causing it to rotate. Currently, downhole screw pumps have the following problems:

[0003] (i) Due to the long depth of the well, in order to achieve high pump efficiency, the length of the downhole screw pump needs to be increased. However, the processing difficulty, welding quality and nitriding effect of the downhole screw pump with increased length cannot be guaranteed.

[0004] (ii) The length of the downhole screw pump is proportional to the downhole depth. If some parts of the downhole screw pump are damaged, the whole pump needs to be replaced, which is costly to maintain and replace.

[0005] (iii) When the well depth is too deep, the pump efficiency requirements of the screw pump are high, but the pump efficiency of conventional screw pumps cannot meet the mining requirements of deep wells. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide a combined downhole pump to solve one or more problems in the prior art.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] A combined downhole pump includes a multi-section pump assembly. Each pump assembly includes a stator and a rotor rotatably disposed inside the stator. A positioner is connected between each section of the pump assembly. The positioner includes a housing assembly and a pumping assembly disposed inside the housing assembly. Both ends of the pumping assembly are connected to the rotor. A casing is also disposed between the outer side of a portion of the pumping assembly and the inner side of the housing assembly. A bearing assembly and a sealing assembly are respectively disposed on the outer side of the casing. At the end of the pumping assembly away from the bearing assembly, an oil passage ring is also disposed on the outer side of the pumping assembly. The oil passage ring has at least one oil passage hole. The end of the oil passage ring away from the casing also has an adjuster, which is also disposed on the outer side of the pumping assembly. One end of the adjuster abuts against the oil passage ring, and the other end of the adjuster extends into the housing assembly.

[0009] Furthermore, the regulator includes a support ring and a straightening connector connected to the support ring.

[0010] Furthermore, the straightening connector includes a connector body, with at least two protrusions on the outer side of the connector body, and a first through hole is opened in the center of the connector body for the oil pumping assembly to pass through.

[0011] Furthermore, the bearing ring includes a bearing ring body, the bearing ring body having a second through hole through which the oil pumping assembly can pass, a conical surface being formed on the bearing ring along the axial direction of the bearing ring, a plurality of openings communicating with the second through hole being formed on the conical surface, and a plurality of oil passage grooves being formed on the bearing ring body.

[0012] Furthermore, the bearing assembly includes a first bearing, a second bearing, and a third bearing, with a spacer provided between the first bearing and the second bearing; the sealing assembly includes a first seal and a second seal, with the second seal disposed close to the third bearing, and a spacer also provided between the second seal and the third bearing.

[0013] Furthermore, the oil extraction assembly includes multiple sucker rods, each adjacent sucker rod being interconnected via a connector, and the sucker rods located at the beginning and end are also connected to the rotor via connectors.

[0014] Furthermore, the housing assembly includes a first housing and a second housing connected to one end of the first housing. The housing assembly also includes an oil pipe, one end of which is connected to the other end of the first housing, and the other end of which is connected to the stator.

[0015] Furthermore, each of the protrusions has an arc edge on its outer side.

[0016] Furthermore, each of the protrusions is equally spaced around the center of the straightening connector.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0018] (I) The present invention sets up a position controller, which can not only realize the connection between each pump assembly, but also set up an adjuster in the housing assembly of the position controller. The adjuster consists of a straightening joint and a bearing ring. By opening a conical surface on the bearing ring, when the sucker rod connected to the straightening joint swings, the guiding effect of the conical surface can further ensure that the straightening joint and the bearing ring are coaxial, thereby ensuring that the sucker rod, the straightening joint and the bearing ring are set coaxially.

[0019] (ii) Furthermore, the bearing ring is used to support the weight of the entire sucker rod. At the same time, by setting the first bearing and the third bearing, the weight applied to the bearing ring can be transferred from the first bearing and the third bearing to the first housing, so as to avoid the problem of mutual wear between the sucker rod and the tubing due to the heavy weight of the collected crude oil.

[0020] (III) The bearing ring is set to realize the assembly of the straightening connector in each control unit. By opening an opening on the bearing ring and setting a protrusion on the outside of the straightening connector that corresponds to the opening, the straightening connector can pass through the second through hole of the bearing ring by rotating the straightening connector so that the protrusion corresponds to the opening, which facilitates the assembly of each control unit.

[0021] (iv) This invention is adaptable to downhole depths. The length can be increased to match the downhole length through assembly. It is also easy to process. If the downhole pump assembly is damaged, a single pump assembly can be replaced, reducing maintenance and replacement costs. Attached Figure Description

[0022] Figure 1 A schematic diagram of a combined downhole pump according to an embodiment of the present invention is shown.

[0023] Figure 2 A cross-sectional structural schematic diagram of a combined downhole pump according to an embodiment of the present invention is shown.

[0024] Figure 3 The diagram shows an enlarged structural schematic of a combined downhole pump at point A according to an embodiment of the present invention.

[0025] Figure 4 An enlarged structural schematic diagram of a combined downhole pump at point B according to an embodiment of the present invention is shown.

[0026] Figure 5 An enlarged structural schematic diagram of a combined downhole pump at point C according to an embodiment of the present invention is shown.

[0027] Figure 6 The diagram shows a connection between a combined downhole pump centering joint and a bearing ring according to an embodiment of the present invention.

[0028] Figure 7 A schematic diagram of the centralizing joint in a combined downhole pump according to an embodiment of the present invention is shown.

[0029] Figure 8 A schematic diagram of the bearing ring in a combined downhole pump according to an embodiment of the present invention is shown.

[0030] The following are labels in the attached diagram: 1. First outer casing; 2. Second outer casing; 3. Oil pipe; 300. First inner hole; 301. Second inner hole; 4. Stator; 5. Sucker rod; 6. Centralizing connector; 600. Connector body; 601. Protrusion; 6010. Arc edge; 602. First through hole; 7. Bearing ring; 700. Bearing ring body; 701. Conical surface; 702. Opening; 703. Second through hole; 704. Oil groove; 8. Oil ring; 800. Oil hole; 9. Connector; 10. Sleeve; 11. First seal; 12. Spacer; 13. First bearing; 14. Second bearing; 15. Third bearing; 16. Second seal; 17. Bearing cover; 18. Rotor. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the following detailed description of a combined downhole pump proposed by this invention, in conjunction with the accompanying drawings and specific embodiments, provides further clarity. The advantages and features of this invention will become clearer from the following description. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, used only to facilitate and clearly illustrate the purpose of the embodiments of this invention. Please refer to the accompanying drawings to make the objectives, features, and advantages of this invention more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation conditions of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by this invention, should still fall within the scope of the technical content disclosed in this invention.

[0032] Please refer to Figure 1 The present invention proposes a combined downhole pump comprising a multi-section pump assembly. Each pump assembly includes a stator 4 and a rotor 20 rotatably disposed within the stator 4. A position controller is also connected between each adjacent pump assembly section. (Please refer to...) Figures 1 to 5 The positioner includes a housing assembly and an oil pumping assembly disposed inside the housing assembly. The two ends of the oil pumping assembly are respectively connected to the rotor 20. The oil pumping assembly and the rotor 20 connected to it can be rotated by the wellhead drive device, thereby realizing the collection of crude oil downhole.

[0033] For further information, please refer to the following: Figures 1 to 5 In order to achieve the connection between each pump assembly, a position controller is also connected between each pump assembly to form a combined pump structure.

[0034] For details, please continue to refer to [the website / information]. Figures 1 to 5The position controller includes a housing assembly and an oil extraction assembly disposed inside the housing assembly, wherein both ends of the oil extraction assembly are connected to the rotor 20. The housing assembly includes a first housing 1 and a second housing 2 connected to one end of the first housing 1. Both the first housing 1 and the second housing 2 are tubular. The housing assembly also includes an oil pipe 3, one end of which is connected to the other end of the first housing 1, and the other end of the oil pipe 3 is connected to the stator 4. Please refer to [reference needed]. Figure 3 The oil pipe 3 has a first inner hole 300 and a second inner hole 301 inside. The first inner hole 300 is used to connect to the outside of the stator 4, and the second inner hole 301 is used to install the oil pumping assembly.

[0035] For further information, please refer to the following: Figures 1 to 5 The oil extraction assembly includes multiple sucker rods 5, wherein each adjacent sucker rod 5 is connected to each other through a connector 9, and the head and tail ends of the multiple sucker rods 5 are also connected to the rotor 18 through connectors 9 respectively.

[0036] For further information, please refer to the following: Figure 4 A sleeve 10 is provided between the outer side of a portion of the oil extraction assembly and the inner side of the outer casing assembly. Specifically, the sleeve 10 is located between the first outer casing 1 and the sucker rod 5, with a portion of the outer side of the sleeve 10 abutting against the inner side of the first outer casing 1, and the sucker rod 5 located inside the sleeve 10. A bearing assembly and a sealing assembly are also provided on the outer side of the sleeve 10's tube body to ensure the sealing of the internal oil extraction. Specifically, the bearing assembly includes a first bearing 13, a second bearing 14, and a third bearing 15, where the first bearing 13 and the third bearing 15 are load-bearing bearings, and the second bearing 14 is a centering bearing. The sealing assembly includes a first seal 11 and a second seal 16, with the second seal 16 positioned close to the third bearing 15. A spacer 12 is also provided between the second seal 16 and the third bearing 15, and the outer side of the second seal 16 is sealed by a bearing cap 17 at its end.

[0037] For further information, please refer to the following: Figures 1 to 5 At the end of the oil pumping assembly furthest from the bearing assembly, an oil passage ring 8 is provided on the outside of the sucker rod 5. One side of the oil passage ring 8 is connected to the casing 10, and the center of the oil passage ring 8 allows the sucker rod 5 to pass through. At least one oil passage hole 800 is opened on the oil passage ring 8, and the crude oil collected by the rotor 18 and the sucker rod 5 through the lifting method after rotation can flow out from the oil passage hole 800. The end of the oil passage ring 8 furthest from the casing 10 also has an regulator, which is also located on the outside of the oil pumping assembly. One end of the regulator abuts against the oil passage ring 8, and the other end of the regulator is connected to part of the outer casing assembly.

[0038] For further information, please refer to the following: Figures 6 to 8The regulator includes a support ring 7 and a straightening connector 6 connected to the support ring 7. In this embodiment, there are three sets of regulators, each with a different size. The straightening connector 6 includes a connector body 600, with at least two protrusions 601 on the outer side of the connector body 600. A first through hole 602 for the oil extraction assembly to pass through is opened at the center of the connector body 600. The support ring 7 includes a support ring body 700, with a second through hole 703 for the oil extraction assembly to pass through. Along the axial direction of the support ring 7, a conical surface 701 is also provided on the support ring 7, with multiple openings 702 communicating with the second through hole 703. Multiple oil passage grooves 704 are also provided on the support ring body 700. The aforementioned conical surface 701 provides guidance for the centralizing connector 6, ensuring it remains centered within the conical surface 701. During oil extraction, the sucker rod 5 oscillates during rotation; the conical surface 701 quickly guides the centralizing connector 6, ensuring it is coaxial with the bearing ring 7. Since the centralizing connector 6 is always in contact with the bearing ring 7, and is partially threaded to the outer side of the sucker rod 5, while maintaining a gap between the outer side of the centralizing connector 6 and the outer side of the tubing 3, the bearing ring 7 bears the entire weight of the sucker rod 5 during extraction. Therefore, the first bearing 13 and the third bearing 15 distribute the weight of the sucker rod 5 and the weight of the lifted crude oil, transferring some of this weight from the bearing ring 7 to the first bearing 13, the third bearing 15, and the first housing 1. This improves the service life of the regulator and prevents wear between the sucker rod 5 and the tubing 3 due to the heavy weight of the extracted crude oil.

[0039] For further information, please refer to the following: Figures 6 to 8Each protrusion 601 in the aforementioned straightening connector 6 has an arc edge 6010 on its outer side. Each protrusion 601 is equally spaced around the center of the straightening connector 6, and the number of openings 702 in the bearing ring 7 is the same as the number of protrusions 601. In actual assembly, the first pump assembly and positioner are installed first. The different sizes of the aforementioned adjusters specifically refer to the different diameters of the second through holes 703 in the bearing ring 7. For example, the second through hole 703 of the bearing ring 7 located at the near end (left end of the downhole pump) in the entire downhole pump structure has the largest diameter, the second through hole 703 of the bearing ring 7 located in the middle section of the downhole pump structure has a smaller diameter than the second through hole 703 of the bearing ring 7 located at the near end, and the second through hole 703 of the bearing ring 7 located at the far end (right end of the downhole pump) has the smallest diameter. Therefore, if the third section When the centralizing connector 6 of the positioner needs to pass through, the centralizing connector 6 passes through the second through hole 703 of the bearing ring 7, that is, through the bearing ring 7 with the largest diameter. Since the bearing ring 7 is installed together with the tubing 3, and the centralizing connector 6 is connected to the outside of the sucker rod 5, the centralizing connector 6 together with the sucker rod 5 can pass through the proximal bearing ring 7 and abut against the distal bearing ring 7, because the diameter of the second through hole 703 of the distal bearing ring 7 is smaller than the outer diameter of the centralizing connector 6. Then, in the same way, the second section of sucker rod 5 and the centralizing connector 6 are passed through the second through hole 703 of the middle section of the bearing ring 7 and abut against the middle section of the bearing ring 7. Finally, the first section of sucker rod 5, the centralizing connector 6 and the second through hole 703 of the proximal bearing ring 7 are connected to complete the assembly of the entire downhole pump.

[0040] Please refer to Figures 1 to 8 The rotor 18 and sucker rod 5 in the deepest pump assembly section of the well rotate to lift the oil from the deep well. Please refer to [reference needed]. Figure 4 During the extraction process, the crude oil located at the sucker rod 5 passes through the oil passage ring 8 and flows out through multiple oil passage holes 800 on the oil passage ring 8 to the space between the oil passage ring 8 and the first outer casing 1. Since a bearing ring 7 is set on one side of the oil passage ring 8, and multiple oil passage grooves 704 are opened on the bearing ring 7, the crude oil flows through the oil passage grooves 704 into the gap between the centralizing joint 6 and the tubing 3, and then flows into the inside of the tubing 3. Since the sucker rod 5 inside the tubing 3 is also connected to another rotor 18 through the joint 9, the crude oil can enter the next pump assembly. That is, after the crude oil is lifted a certain distance by the first pump assembly, it flows through the first positioner and about 200m of tubing 3 into the second pump assembly. Then, the crude oil is lifted a certain distance by the second pump assembly and flows through the second positioner into the third pump assembly. This cycle continues until it is lifted to the wellhead, thereby maintaining high pump efficiency in deep well extraction. Each positioner can decompose the weight of the crude oil, which can reduce the weight and avoid uneven wear.

[0041] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A combined downhole pump, comprising a multi-section pump assembly, the pump assembly including a stator and a rotor rotatably disposed inside the stator, characterized in that: Each pump assembly is connected to a position controller, which includes a housing assembly and an oil-suction assembly disposed inside the housing assembly. The two ends of the oil-suction assembly are respectively connected to the rotor. A sleeve is also disposed between the outer side of a portion of the oil-suction assembly and the inner side of the housing assembly. A bearing assembly and a sealing assembly are respectively disposed on the outer side of the sleeve. At the end of the oil-suction assembly away from the bearing assembly, an oil passage ring is also disposed on the outer side of the oil-suction assembly. The oil passage ring has at least one oil passage hole. The end of the oil passage ring away from the sleeve also has an adjuster. The adjuster is also disposed on the outer side of the oil-suction assembly. One end of the adjuster abuts against the oil passage ring, and the other end of the adjuster extends into the housing assembly.

2. A combined downhole pump as described in claim 1, characterized in that: The regulator includes a support ring and a straightening connector connected to the support ring.

3. A combined downhole pump as described in claim 2, characterized in that: The straightening connector includes a connector body, with at least two protrusions on the outer side of the connector body, and a first through hole in the center of the connector body for the oil pumping assembly to pass through.

4. A combined downhole pump as described in claim 3, characterized in that: The bearing ring includes a bearing ring body, which has a second through hole through which the oil pumping assembly can pass. Along the axial direction of the bearing ring, a conical surface is also formed on the bearing ring, and multiple openings that can communicate with the second through hole are formed on the conical surface. Multiple oil passage grooves are also formed on the bearing ring body.

5. A combined downhole pump as described in claim 4, characterized in that: The bearing assembly includes a first bearing, a second bearing, and a third bearing, with a spacer provided between the first bearing and the second bearing; the sealing assembly includes a first seal and a second seal, with the second seal disposed close to the third bearing, and a spacer also provided between the second seal and the third bearing.

6. A combined downhole pump as described in claim 4, characterized in that: The oil extraction assembly includes multiple sucker rods, each adjacent sucker rod is connected to the others via a connector, and the sucker rods located at the beginning and end are also connected to the rotor via connectors.

7. A combined downhole pump as described in claim 1, characterized in that: The housing assembly includes a first housing and a second housing connected to one end of the first housing. The housing assembly also includes an oil pipe, one end of which is connected to the other end of the first housing, and the other end of which is connected to the stator.

8. A combined downhole pump as described in claim 3, characterized in that: Each of the protrusions has an arc edge on its outer side.

9. A combined downhole pump as described in claim 3, characterized in that: Each of the protrusions is equally spaced from the center of the straightening joint.

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