Dynamic pressure balance dynamic seal deep well high-speed internal lift pump

Abstract

The utility model discloses a dynamic pressure balance dynamic seal deep well high-speed internal lift pump, and relates to the technical field of deep well pump design. The upper end cover and the lower end cover are in threaded connection with the two ends of the pump shell, a liquid inlet hole is formed in the lower end cover, the stator and the winding are fixed to the upper portion of the inner wall of the pump shell, and the open end of an annular cylinder of the annular differential pressure balancer faces downwards and is in threaded connection with the lower portion of the inner wall of the pump shell. A reset spring is supported between an annular plug and a lower end cover, a hollow main shaft of the rotor assembly is rotationally installed between an upper end cover and the lower end cover, a silicon steel sheet is fixed to the upper portion of the outer wall of the hollow main shaft, and O-shaped movable sealing rings are arranged between the hollow main shaft and an annular cylinder and between the hollow main shaft and the upper end cover. And spiral strips are arranged around the central shaft and are fixedly connected with the inner wall of the hollow main shaft through welding spots. The hollow main shaft of the motor rotor assembly serves as a flow channel, the spiral strip pieces are welded in the flow channel, abrasion is not prone to occurring, and the annular differential pressure balancer is additionally arranged to avoid leakage at the dynamic sealing position in the high-pressure environment.

Description

Technical Field

[0001] The utility model relates to the technical field of deep well pump design, in particular to a deep well high-speed internal lifting pump with dynamic pressure balance and dynamic seal. Background Art

[0002] With the continuous development of my country's petroleum industry, most oil fields have entered the mid-to-late stage of exploitation. In the mid-to-late stage, the oil wells in the oil fields are too deep and the oil well production is reduced, which is no longer suitable for high-energy consumption and low-efficiency oil extraction methods. Most traditional oil production pumps use industrial frequency motors with low power density. They require multiple pump bodies to be connected in series to obtain high lift. In addition, the friction between the impurities in the formation liquid and the pump body can easily cause the pump body to wear, and the service life is not long. There are high requirements for the presence of impurities in the liquid. In addition, because the working environment is in a deep well and the environmental pressure is high, it is difficult to seal dynamically. It is easy for the liquid in the working environment to enter the pump body through the dynamic seal due to the high pressure difference between the inside and outside of the pump, causing work failure.

[0003] The Chinese utility model patent with announcement number CN217813977U, announcement date November 15, 2022, and name is a hollow through-shaft pump. The center of the motor shaft of the water pump is through, but there is still an impeller externally connected to the motor shaft. This has certain requirements on the strength of the mechanical structure and the stability of the working environment. Under high-speed working conditions, the impeller is prone to friction and collision with impurities and debris in the transported liquid, thereby damaging the impeller. The design of the external impeller is not conducive to the series connection of multiple water pumps. Utility Model Content

[0004] In order to address the deficiencies in the background technology, the utility model provides a deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal. The hollow main shaft of the motor rotor assembly is used as the flow channel, and spiral strips are welded inside for pushing up the liquid. It is not easy to get clogged and helps to reduce wear. The addition of an annular pressure difference balancer can achieve dynamic balance of the pressure inside and outside the pump, avoiding leakage at the dynamic seal under high-pressure environment, and facilitating the use of multiple units in series.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal, including a pump housing, an upper end cover, a lower end cover, a stator and windings, a rotor assembly, an annular pressure difference balancer and a reset spring, the pump housing is a cylindrical component, the upper end cover and the lower end cover are both annular components and are respectively threadedly connected and fixed to the upper and lower ends of the pump housing, the lower end cover is processed to open a liquid inlet hole, the stator and windings are fixed to the upper part of the inner wall of the pump housing, the annular pressure difference balancer includes an annular cylinder and an annular plug, the open end of the annular cylinder faces downward and its outer wall is threadedly connected and fixed to the lower part of the inner wall of the pump housing, the annular plug sliding seal is inserted into the open end of the annular cylinder and is internally A cylinder chamber is formed, and a balancing hole is machined into the closed end of the annular cylinder. The reset spring is supported between the annular plug and the lower end cover. The rotor assembly includes a hollow main shaft, a spiral strip, a central shaft and a silicon steel sheet. The hollow main shaft is coaxially rotatably installed between the central holes of the upper end cover and the lower end cover. The silicon steel sheet is fixed to the upper part of the outer wall of the hollow main shaft and is gap-matched with the area where the stator and the winding are located. A first O-type dynamic sealing ring is arranged between the hollow main shaft and the annular cylinder, and a second O-type dynamic sealing ring is arranged between the hollow main shaft and the upper end cover. The central shaft is coaxially and arranged throughout the length of the hollow main shaft. Spiral strips are machined around the central shaft, and the edges of the spiral strips are connected and fixed to the corresponding positions of the inner wall of the hollow main shaft by welding points.

[0006] Furthermore, the lower end surface of the lower end cover is configured as a tapered surface whose thickness gradually decreases from the edge toward the center hole.

[0007] Furthermore, the upper and lower ends of the silicon steel sheet of the rotor assembly and the cavity between the upper end cover and the annular cylinder respectively form an upper oil cavity and a lower oil cavity, and both the upper oil cavity and the lower oil cavity are filled with cooling lubricating oil.

[0008] Furthermore, the annular plug includes a plug body and a plug seat. The plug body is slidingly sealed and inserted into the opening end of the annular cylinder. The plug seat is formed by extending and thickening the bottom end of the plug body inward and outward.

[0009] Furthermore, the upper end cover is processed to open threading holes for leading out the stator, winding and power connection wires and is sealed.

[0010] Furthermore, an outer sliding sealing ring and an inner sliding sealing ring are respectively arranged on both sides of the inner wall of the annular cylinder near the open end, the outer sliding sealing ring is in close contact with the outer ring surface of the annular plug, and the inner sliding sealing ring is in close contact with the inner ring surface of the annular plug.

[0011] Furthermore, a first O-type static sealing ring is arranged between the annular cylinder and the pump housing.

[0012] Furthermore, a second O-type static sealing ring is arranged between the upper end cover and the pump housing.

[0013] Furthermore, there are multiple balancing holes, which are arranged at equal intervals along the circumferential direction at the closed end of the annular cylinder, and the diameters of the multiple balancing holes are consistent.

[0014] Furthermore, there are a plurality of liquid inlet holes which are arranged at equal intervals along the circumferential direction on the lower end cover, and the diameters of the plurality of liquid inlet holes remain consistent.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1. The utility model uses the hollow main shaft of the motor rotor assembly as the flow channel, the motor and the pump are integrated, the power density is large, the working speed can be adjusted by adjusting the power frequency, and it is easy to achieve high speed, and the displacement and head range is large;

[0017] 2. The hollow main shaft of the utility model as a flow channel has a large open space, and spiral strips are welded inside the hollow main shaft. When started, the spiral strips push the liquid up at high speed, and there is no relative friction between the blade group and the pump body. It is not easy to be blocked and has low requirements for the transported liquid. In high-speed working scenarios, it is not easy to cause the pump body to wear due to friction between impurities in the liquid and the pump body. It has a long working life and is suitable for various liquids and a wide range of application scenarios;

[0018] 3. The utility model can achieve dynamic balance of pressure inside and outside the pump in a deep well high-pressure working environment through an annular pressure differential balancer, and the dynamic sealing effect is better, so that the pump can also work stably in a deep well high-pressure working environment, and will not cause the liquid in the working environment to penetrate into the pump body through the dynamic seal due to the high pressure difference and cause working failure;

[0019] 4. The utility model has a simple overall structure, low processing difficulty, and a slender volume that makes it easy to connect multiple units in series. The ground process flow is simple and easy to manage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the overall structure of the utility model deep well high-speed internal lifting pump;

[0021] Figure 2 It is a structural schematic diagram of the annular pressure difference balancer of the deep well high-speed internal lift pump of the utility model;

[0022] Figure 3 The utility model is an axonometric schematic diagram of the spiral strips of the deep well high-speed internal lift pump.

[0023] In the figure: 1-pump housing, 2-upper end cover, 3-lower end cover, 4-stator and winding, 5-rotor assembly, 501-hollow main shaft, 502-spiral strip, 503-center shaft, 504-silicon steel sheet, 505-welding point, 6-threading hole, 7-annular pressure difference balancer, 701-annular cylinder, 702-annular plug, 7021-plug body, 7022-plug seat, 703-cylinder chamber, 704-balancing hole, 705-intermediate positioning bearing, 706-outer sliding sealing ring, 707-inner sliding sealing ring, 708-first O-type static sealing ring, 709-first O-type dynamic sealing ring, 8-liquid inlet hole, 9-reset spring, 10-upper oil chamber, 11-lower oil chamber, 12-upper positioning bearing, 13-lower positioning bearing, 14-second O-type dynamic sealing ring, 15-second O-type static sealing ring. DETAILED DESCRIPTION

[0024] The technical solution of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0025] like Figure 1 to Figure 3 As shown, a deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal includes a pump housing 1, an upper end cover 2, a lower end cover 3, a stator and winding 4, a rotor assembly 5, a threading hole 6, an annular pressure difference balancer 7, a liquid inlet hole 8, a reset spring 9, an upper oil chamber 10, a lower oil chamber 11, an upper locating bearing 12, a lower locating bearing 13, a second O-type dynamic seal ring 14, and a second O-type static seal ring 15.

[0026] Combination Figure 1 As shown, the pump housing 1 is a cylindrical component, and the upper end cover 2 and the lower end cover 3 are both annular components and are respectively threaded and fixed to the upper and lower ends of the pump housing 1. Among them, the upper end cover 2 can be processed to open a threading hole 6 for the stator and winding 4 to lead out the power connection line and perform a sealing treatment, and the lower end cover 3 can be processed to open a liquid inlet hole 8. The number of the liquid inlet holes 8 can be set to multiple and arranged at equal intervals along the circumference of the lower end cover 3. The diameters of the multiple liquid inlet holes 8 are consistent, so that the liquid in the working environment can enter the bottom space of the pump housing 1 through the liquid inlet holes 8 to balance the pressure between the working environment. The stator and winding 4 are fixed to the upper part of the inner wall of the pump housing 1, and form an AC permanent magnet synchronous motor structure with the rotor assembly 5. The motor speed can be increased by increasing the power frequency, thereby increasing the pump head, improving the traditional pump speed-up method through the gear set, so that the utility model does not need to consider the loss of the gear set, improves the service life, and reduces the maintenance cost.

[0027] Combination Figure 2 As shown, the annular pressure differential balancer 7 includes an annular cylinder 701 and an annular plug 702, the open end of the annular cylinder 701 faces downward and its outer wall is threadedly fixed to the lower part of the inner wall of the pump housing 1, the annular plug 702 is slidingly sealed and inserted into the open end of the annular cylinder 701 to form a cylinder chamber 703 inside, and a balancing hole 704 is processed at the closed end of the annular cylinder 701. The number of balancing holes 704 can be set to multiple and are arranged at equal intervals along the circumferential direction at the closed end of the annular cylinder 701. The diameters of the multiple balancing holes 704 are kept consistent, which is used to connect the cylinder chamber 703 with the lower oil chamber 11 and balance the pressure between the two.

[0028] Combination Figure 1 As shown, the return spring 9 is supported between the annular plug 702 and the lower end cover 3, so that the annular plug 702 will not be dislocated from the annular cylinder 701, and the influence of the self-weight of the annular plug 702 on the operation of the annular pressure differential balancer 7 is eliminated. In order to enable the return spring 9 to provide a wider and more stable force-bearing platform for the annular plug 702, the annular plug 702 includes a plug body 7021 and a plug seat 7022. The plug body 7021 is inserted into the opening end of the annular cylinder 701 in a sliding seal, and the plug seat 7022 is formed by extending and thickening the bottom end of the plug body 7021 inward and outward, thereby ensuring more effective contact between the annular plug 702 and the return spring 9. The rotor assembly 5 includes a hollow main shaft 501, a spiral strip 502, a central shaft 503 and a silicon steel sheet 504. The hollow main shaft 501 is coaxially rotatably installed between the center holes of the upper end cover 2 and the lower end cover 3 through the upper positioning bearing 12 and the lower positioning bearing 13. The annular pressure difference balancer 7 and the reset spring 9 are passed through the bottom of the hollow main shaft 501. An intermediate positioning bearing 705 can be added between the hollow main shaft 501 and the annular pressure difference balancer 7. The three upper, middle and lower positioning bearings can well position the hollow main shaft 501 and the entire rotor assembly 5, which helps to ensure the stability of the rotor assembly 5 during high-speed rotation. The silicon steel sheet 504 is fixed on the upper part of the outer wall of the hollow main shaft 501 and is gap-matched with the area where the stator and winding 4 are located. The upper and lower ends of the silicon steel sheet 504 of the rotor assembly 5 and the cavity between the upper end cover 2 and the annular cylinder 701 form an upper oil chamber 10 and a lower oil chamber 11, respectively, and the upper oil chamber 10 and the lower oil chamber 11 are filled with cooling lubricating oil. A first O-ring 709 is provided between the hollow main shaft 501 and the annular cylinder 701, and a second O-ring 14 is provided between the hollow main shaft 501 and the upper end cover 2 to prevent the liquid in the working environment from connecting with the cooling lubricating oil in the pump through the gaps of the two rotating connections of the hollow main shaft 501 and causing working abnormalities.

[0029] Combination Figure 1 , Figure 3As shown, the central axis 503 is coaxially and fully arranged in the hollow main axis 501 , and a spiral strip 502 is processed and arranged around the central axis 503 . The edge of the spiral strip 502 is connected and fixed to the corresponding position of the inner wall of the hollow main axis 501 through a welding point 505 .

[0030] Combination Figure 1 As shown, in order to further ensure the sealing performance inside the pump, an outer sliding seal ring 706 and an inner sliding seal ring 707 are respectively arranged near the open end on both sides of the inner wall of the annular cylinder 701, the outer sliding seal ring 706 is in close contact with the outer ring surface of the annular plug 702, and the inner sliding seal ring 707 is in close contact with the inner ring surface of the annular plug 702. A first O-type static seal ring 708 is arranged between the annular cylinder 701 and the pump housing 1 to prevent the liquid in the working environment from passing through the sliding connection position of the annular pressure difference balancer 7 and the threaded connection gap to communicate with the cooling lubricating oil in the pump and cause abnormal operation. A second O-type static seal ring 15 is arranged between the upper end cover 2 and the pump housing 1 to prevent the liquid in the working environment from entering the stator and winding 4 and rotor assembly 5 in the pump body through the threaded connection gap between the pump housing 1 and the upper end cover 2 and cause abnormal operation.

[0031] Combination Figure 1 As shown, in addition, the lower end surface of the lower end cover 3 is preferably set as a conical surface with a thickness gradually decreasing from the edge to the center hole, so that the flow velocity change caused by the collision of the transported liquid and impurities with the lower end surface of the lower end cover 3 when entering from the lower end of the hollow main shaft 501 is smoother, which is conducive to increasing the flow rate.

[0032] The deep well high-speed internal lifting pump of the utility model is a mechanical device for conveying fluid or pressurizing fluid with an integrated design of a motor and a pump body, and can be used for but not limited to lifting oil and gas in oil wells. The hollow main shaft 501 serves as a flow channel to convey liquid from bottom to top. The stator and winding 4 and the rotor assembly 5 are the basic components of the motor, which are conventional structures, and their specific structures are not described again. When the motor part is started, the rotor assembly 5 rotates at a high speed to suck the liquid from the lower end of the hollow main shaft 501, which is lifted by the spiral strip 502 and finally discharged from the upper end of the hollow main shaft 501.

[0033] When entering a high-pressure working environment, the liquid in the working environment enters the space between the annular pressure differential balancer 7 and the lower end cover 3 at the bottom of the pump housing 1 from the liquid inlet hole 8 of the lower end cover 3, and the pressure between the space under the annular pressure differential balancer 7 and the working environment is balanced. When the pressure of the space under the annular pressure differential balancer 7 is greater than the pressure of the pump space formed by the gap between the cylinder chamber 703, the upper oil chamber 10, the lower oil chamber 11, the stator and the winding 4, and the rotor assembly 5, the annular plug 702 will rise under the action of the pressure difference, thereby reducing the space in the cylinder chamber 703 and increasing the pressure, until the pressure is the same as the pressure of the working environment, the annular plug 702 stops moving, and the pressure of the space inside the pump and the space outside the pump reaches a dynamic balance, that is, the pressure on both sides of the first O-type dynamic seal 709 and the second O-type dynamic seal 14 is balanced, so that the dynamic sealing effect is optimized and leakage at the dynamic seal under high-pressure environment is avoided.

[0034] Compared with the traditional pump structure, the utility model adopts the design of the hollow main shaft 501 with internally welded spiral strips 502, so that the flow channel of the pump is simplified and completely open, and the requirements for the transported liquid are extremely low. The impurities and debris therein can also be directly discharged along the hollow main shaft 501, eliminating the failure of debris blocking the pump. The spiral strips 502 are used to lift the circulating liquid. Under the condition of high-speed operation, there will be no wear of the water pump due to the friction between the impurities and debris and the blades and the pump body, and it can work for a long time under high speed. In addition, the utility model adopts the design of the annular pressure differential balancer 7, through which the internal and external pressures of the pump can reach a dynamic balance, avoiding the negative impact of easy leakage caused by the pressure difference on both sides of the dynamic seal, and making the dynamic seal reach the most ideal state.

[0035] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other forms of assembly without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes within the meaning and scope of the equivalents of the claims be included in the present invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0036] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal, characterized in that: The pump housing (1) comprises a pump housing (1), an upper end cover (2), a lower end cover (3), a stator and windings (4), a rotor assembly (5), an annular pressure difference balancer (7) and a return spring (9), wherein the pump housing (1) is a cylindrical component, the upper end cover (2) and the lower end cover (3) are both annular components and are respectively threadedly connected and fixed to the upper and lower ends of the pump housing (1), the lower end cover (3) is processed to open a liquid inlet hole (8), and the stator and windings (4) are fixed in the pump housing (1). The annular pressure differential balancer (7) comprises an annular cylinder (701) and an annular plug (702), the opening end of the annular cylinder (701) faces downward and the outer wall thereof is threadedly connected and fixed to the lower part of the inner wall of the pump housing (1), the annular plug (702) is inserted into the opening end of the annular cylinder (701) in a sliding seal and forms a cylinder chamber (703) inside, the closed end of the annular cylinder (701) is machined to open a balancing hole (704), the reset spring (9) is supported on the annular plug ( The rotor assembly (5) comprises a hollow main shaft (501), spiral strips (502), a central shaft (503) and a silicon steel sheet (504). The hollow main shaft (501) is coaxially rotatably mounted between the central holes of the upper end cover (2) and the lower end cover (3). The silicon steel sheet (504) is fixed to the upper part of the outer wall of the hollow main shaft (501) and is clearance-matched with the area where the stator and the winding (4) are located. A first O-type dynamic seal ring (709) is arranged between the annular cylinders (701), a second O-type dynamic seal ring (14) is arranged between the hollow main shaft (501) and the upper end cover (2), the central shaft (503) is coaxially and arranged throughout the hollow main shaft (501), a spiral strip (502) is processed and arranged around the central shaft (503), and the edge of the spiral strip (502) is connected and fixed to the corresponding position of the inner wall of the hollow main shaft (501) through a welding point (505).

2. A deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: The lower end surface of the lower end cover (3) is arranged as a tapered surface whose thickness gradually decreases from the edge toward the center hole.

3. A deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1 or 2, characterized in that: The upper and lower ends of the silicon steel sheet (504) of the rotor assembly (5) and the cavity between the upper end cover (2) and the annular cylinder (701) respectively form an upper oil chamber (10) and a lower oil chamber (11), and both the upper oil chamber (10) and the lower oil chamber (11) are filled with cooling lubricating oil.

4. The deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: The annular plug (702) comprises a plug body (7021) and a plug seat (7022). The plug body (7021) is inserted into the opening end of the annular cylinder (701) in a sliding and sealing manner. The plug seat (7022) is formed by extending and thickening the bottom end of the plug body (7021) inward and outward directions.

5. The deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: The upper end cover (2) is processed to form a threading hole (6) for leading out the stator and winding (4) and the power connection wire, and is sealed.

6. The deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: An outer sliding sealing ring (706) and an inner sliding sealing ring (707) are respectively arranged on both sides of the inner wall of the annular cylinder (701) adjacent to the open end. The outer sliding sealing ring (706) is in close contact with the outer ring surface of the annular plug (702), and the inner sliding sealing ring (707) is in close contact with the inner ring surface of the annular plug (702).

7. The deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: A first O-type static sealing ring (708) is arranged between the annular cylinder (701) and the pump housing (1).

8. The deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: A second O-type static sealing ring (15) is arranged between the upper end cover (2) and the pump housing (1).

9. The deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: The balancing holes (704) are multiple in number and are arranged at equal intervals along the circumferential direction at the closed end of the annular cylinder (701), and the diameters of the multiple balancing holes (704) are consistent.

10. The deep well high-speed internal lift pump with dynamic pressure balance and dynamic seal according to claim 1, characterized in that: The number of the liquid inlet holes (8) is plural and they are arranged at equal intervals along the circumferential direction on the lower end cover (3), and the diameters of the multiple liquid inlet holes (8) remain consistent.

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