Magnetic suspension high-speed internal lift pump for deep well mining

Abstract

The invention discloses a magnetic suspension high-speed internal lift pump for deep well mining, and relates to the technical field of fluid machinery, the magnetic suspension high-speed internal lift pump comprises a pump body, the pump body is composed of an upper end cover, a middle shell and a lower end cover which are detachably connected from top to bottom in the axial direction, and a through fluid channel is arranged in the pump body; the integrated overflowing structure is arranged in the fluid channel and comprises a vertical center shaft, spiral blades spirally distributed on the center shaft and an annular shell arranged outside the spiral blades; the motor assembly is contained in the middle section shell and used for driving the integrated overflowing structure to rotate so as to increase the fluid pressure. The main axial load borne by the center bearing is actively shared through the magnetic suspension assembly, the stress working condition of the bottom auxiliary mechanical bearing is effectively improved, and therefore the service life of the bearing and the whole pump body in the deep well high-pressure and high-impurity environment can be prolonged, and the operation reliability is improved.

Description

Technical Field

[0001] This invention relates to the field of fluid machinery technology, and more specifically to a magnetically levitated high-speed internal lift pump for deep well mining. Background Technology

[0002] Deep well extraction, such as the extraction of resources like oil, geothermal energy, and mineral water, typically requires pumping fluids from hundreds to thousands of meters underground to the surface. In this application, submersible pumps or internal lift pumps are the core transport equipment. Current technologies generally employ multi-stage centrifugal pump structures, with the drive motor usually located in the middle or lower part of the pump body, connected to the impeller via a long shaft. To withstand the enormous axial water thrust and rotor weight, the pump body typically houses multiple mechanical bearings (such as angular contact ball bearings or sliding bearings) as central shaft supports. The motor type is primarily asynchronous induction motors or ordinary permanent magnet synchronous motors, with speed regulation achieved through frequency converters to adapt to different head and flow rate requirements. For sealing, packing seals, mechanical seals, or a combination of seals are often used at the shaft extension to cope with the high-pressure fluid environment downhole.

[0003] However, in the harsh conditions of deep well mining, this traditional structure, with its flow passage composed of multiple independent impellers, guide vanes, and shell chambers, has numerous joints and gaps, making it impossible to form a completely continuous sealed cavity. This results in internal volumetric losses during pump operation, reducing volumetric efficiency. Secondly, its core working mechanism relies on a precise "stator-rotor" clearance fit (i.e., the radial clearance between the impeller and guide vanes), which is directly exposed to the high-speed flowing, sand-laden, high-pressure well fluid. Solid impurities in the transported medium can easily enter this gap, causing severe abrasive wear on the impeller and guide vane surfaces. This not only leads to increased clearance and leakage, but also a rapid decline in pump efficiency. In severe cases, it can even cause rotating parts to seize due to particle jamming, leading to catastrophic mechanical failures. Furthermore, to drive multi-stage impellers, traditional pumps must use slender drive shafts and multiple intermediate bearings, resulting in a complex mechanical structure, long axial dimensions, and heavy weight. This not only increases the difficulty and cost of downhole installation, but also reduces the overall system efficiency due to mechanical losses in the drive chain.

[0004] Meanwhile, like all deep well pumps, its bearing system must withstand the enormous axial water thrust generated by the multi-stage impellers and the rotor's own weight. Under such continuous high loads and harsh lubrication conditions, traditional mechanical bearings are highly susceptible to premature wear and fatigue failure, becoming another key bottleneck limiting the pump's lifespan. Once a bearing or flow component fails in a deep well, replacement requires pulling out the entire pump string, resulting in a long operation cycle, extremely high costs, and severely impacting the continuity of extraction and economic efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a magnetically levitated high-speed internal lift pump for deep well mining, in order to solve the problems in the prior art, such as severe internal leakage due to structural design limitations, sensitivity and susceptibility to impurities in the transported medium, complex mechanical structure and low efficiency, and short life of mechanical bearings under huge axial loads.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a magnetic levitation high-speed internal lift pump for deep well mining, comprising a pump body, wherein the pump body is composed of a detachably connected upper end cover, a middle section shell and a lower end cover along the axial direction from top to bottom, and the pump body is provided with a through fluid channel inside.

[0007] An integrated flow passage structure is disposed within the fluid channel, comprising a vertical central shaft, spiral blades arranged spirally on the central shaft, and an annular shell disposed outside the spiral blades;

[0008] A motor assembly, housed within the middle housing, is used to drive the integrated flow structure to rotate in order to increase fluid pressure;

[0009] A magnetic levitation assembly is disposed between the motor assembly and the lower end cover. The magnetic levitation assembly includes a rotating magnet assembly fixed to the annular housing and a stationary magnet assembly fixed to the pump body.

[0010] The rotating magnet assembly and the stationary magnet assembly interact through magnetic fields, jointly bearing the main axial load acting on the integrated flow structure and distributing this axial load to the pump body; and

[0011] An auxiliary mechanical bearing is disposed below the magnetic levitation assembly and mounted on the middle housing to provide radial support for the central shaft.

[0012] Furthermore, the motor assembly, from the outside to the inside, includes: a stator core and windings fixed inside the middle housing, a Halebeck array permanent magnet ring arranged circumferentially outside the stator core and windings, a magnet protective cover wrapped around the Halebeck array permanent magnet rings, and a hollow motor shaft, with the central shaft fixedly passing through the hollow motor shaft.

[0013] Furthermore, the inner wall of the hollow motor shaft is provided with annularly distributed mating grooves, and the outer wall of the annular housing is provided with annularly distributed keyways, the keyways cooperating with the mating grooves.

[0014] Furthermore, an annular magnetic shielding plate fixed to the pump body is provided between the bottom of the motor assembly and the top of the magnetic levitation assembly. The annular magnetic shielding plate is made of a conductive but non-magnetic material.

[0015] Furthermore, a mechanical seal is provided between the upper end cover and the central shaft, the mechanical seal being configured to withstand a static hydraulic pressure of at least 20 MPa.

[0016] Furthermore, the inlet and outlet of the fluid channel are also provided with a skeleton oil seal to prevent impurities from entering the motor assembly.

[0017] Furthermore, the magnetic levitation assembly includes at least two stages of magnetic force bearing units arranged in series along the central axis.

[0018] Each stage of the magnetic force bearing unit includes a first annular magnet fixed on the central shaft and a second annular magnet fixed on the pump body;

[0019] Within the same magnetic force bearing unit, the end faces of the first annular magnet and the second annular magnet that are axially opposite to each other are opposite magnetic poles, and the two are combined by magnetic attraction.

[0020] Between two adjacent magnetic bearing units, the end faces of the second annular magnet in the upper level and the first annular magnet in the lower level that are axially opposite to each other are magnetic poles of the same polarity, and an axial suspension gap is formed between them by magnetic repulsion.

[0021] Furthermore, the magnetic levitation component has three stages.

[0022] Furthermore, in the magnetic bearing unit, the first annular magnet and the second annular magnet are in contact under the action of axial magnetic attraction.

[0023] Compared with existing technologies, the magnetic levitation high-speed internal lift pump for deep well mining provided by this invention adopts an "integrated flow structure," which integrates the helical blades, central shaft, and external annular shell into a single unit, forming a continuous, leak-free, sealed pressurization chamber. This avoids the volumetric losses caused by gaps in traditional multi-stage pumps, thus improving the pump's volumetric efficiency. Simultaneously, this design physically isolates the critical "stator-rotor" mating surface (i.e., the outer edge of the helical blades and the inner wall of the annular shell) from the main flow channel, preventing solid particles in the conveyed medium from contacting and abrading this mating surface. This achieves a high degree of insensitivity to the conveyed medium, extending the pump's wear resistance and operational reliability under conditions containing sand and impurities.

[0024] Furthermore, this invention adopts an "integrated pump and motor" design, which directly integrates the flow structure that performs work on the fluid onto the central shaft, eliminating the lengthy drive shaft and couplings of traditional pumps. This results in an extremely simplified overall structure, a significantly shortened axial dimension, and a lighter weight. Moreover, the use of a high-efficiency permanent magnet synchronous motor achieves lower energy loss and higher system efficiency.

[0025] Building upon this, the present invention utilizes a magnetic levitation component positioned below the motor assembly. This component's magnetic field actively bears and disperses most of the axial load acting on the rotor, directly transmitting the force to the pump body structure. This design allows the auxiliary mechanical bearing at the end to bear only radial support and the remaining small amount of axial load, effectively avoiding the premature wear and failure problems caused by bearings bearing the entire enormous axial force in traditional deep well pumps. Based on these multiple structural advantages, the pump unit of the present invention exhibits long service life, high efficiency, and high reliability under deep well high-pressure and high-impurity conditions. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0027] Figure 1 This is a schematic diagram of the overall structure of a magnetically levitated high-speed internal lift pump for deep well mining provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of the magnetic levitation assembly and auxiliary mechanical bearings provided in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the overall structure of the motor assembly provided in an embodiment of the present invention;

[0030] Figure 4 This is a schematic diagram of the magnetization direction structure of the Heilbeck array permanent magnet ring provided in an embodiment of the present invention;

[0031] Figure 5 This is a schematic diagram of the hollow central shaft component of the motor provided in an embodiment of the present invention;

[0032] Figure 6 This is a cross-sectional view of the annular shell component structure provided in an embodiment of the present invention;

[0033] Figure 7 This is a schematic diagram of the structure of components such as the central shaft and helical blades provided in an embodiment of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Pump body; 101. Upper end cover; 102. Middle section housing; 103. Lower end cover; 2. Fluid passage; 3. Motor assembly; 301. Stator core and windings; 302. Helbeck array permanent magnet ring; 303. Magnet protective cover; 304. Hollow motor shaft; 4. Magnetic levitation assembly; 401. First annular magnet; 402. Second annular magnet; 5. Auxiliary mechanical bearing; 6. Connecting groove; 7. Key; 8. Annular housing; 9. Annular magnetic shield; 10. Mechanical seal; 11. Skeleton oil seal; 12. Axial suspension clearance; 13. Central shaft; 14. Helical blades. Detailed Implementation

[0036] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0037] As attached Figure 1 To be continued Figure 7 As shown:

[0038] Example:

[0039] The present invention provides a magnetic levitation high-speed internal lift pump for deep well mining, including a pump body 1. The pump body 1 is composed of an upper end cover 101, a middle section shell 102 and a lower end cover 103 that are detachably connected from top to bottom along the axial direction, and the pump body 1 is provided with a through fluid channel 2 inside.

[0040] An integrated flow structure is provided in the fluid channel 2, which includes a vertical central shaft 13, spiral blades 14 spirally distributed on the central shaft 13, and an annular shell 8 placed outside the spiral blades 14;

[0041] Motor assembly 3, housed within the middle section housing 102, is used to drive the integrated flow structure to rotate in order to increase fluid pressure;

[0042] A magnetic levitation component 4 is disposed between the motor component 3 and the lower end cover 103. The magnetic levitation component 4 includes a rotating magnet assembly fixed on the annular housing 8 and a stationary magnet assembly fixed on the pump body 1.

[0043] The rotating magnet assembly and the stationary magnet assembly interact through magnetic fields, jointly bearing the main axial load acting on the integrated flow structure and distributing this axial load to the pump body 1; and

[0044] An auxiliary mechanical bearing 5 is disposed below the magnetic levitation assembly 4 and mounted on the middle housing 102 to provide radial support for the central shaft 13.

[0045] It should be noted that by adopting an "integrated flow structure," the helical blades 14, the central shaft 13, and the external annular housing 8 are integrated into a single unit, forming a continuous, leak-free, sealed pressure-boosting chamber. This avoids the volumetric losses caused by gaps in traditional multistage pumps, thus improving the pump's volumetric efficiency. Simultaneously, this design physically isolates the critical "stator-rotor" mating surface (i.e., the outer edge of the helical blades 14 and the inner wall of the annular housing 8) from the main flow channel, preventing solid particles in the conveyed medium from contacting and abrading this mating surface. This achieves a high degree of insensitivity to the conveyed medium, extending the pump's wear resistance and operational reliability under conditions containing sand and impurities.

[0046] Furthermore, the present invention adopts an "integrated pump and motor" design, which directly integrates the flow structure that performs work on the fluid onto the central shaft 13, eliminating the lengthy drive shaft and coupling of traditional pumps. This results in an extremely simplified overall structure, a significantly shortened axial dimension, and a lighter weight. Moreover, the use of a high-efficiency permanent magnet synchronous motor achieves lower energy loss and higher system efficiency.

[0047] Based on this, the present invention utilizes a magnetic levitation component 4 located below the motor assembly 3 to actively bear and disperse most of the axial load acting on the rotor using its magnetic field force, directly transmitting the force to the pump body 1 structure. This design allows the auxiliary mechanical bearing 5 at the end to bear only radial support and the remaining small amount of axial load, effectively avoiding the premature wear and failure problems caused by the bearings bearing all the huge axial forces in traditional deep well pumps. Based on the above multiple structural advantages, the pump set of the present invention exhibits advantages of long service life, high efficiency, and high reliability under deep well high pressure and high impurity conditions.

[0048] Additionally, the auxiliary mechanical bearing 5 is an angular contact ball bearing or a sliding bearing, and its bearing cavity is sealed and isolated from the motor cavity. The cavity is filled with a special high-temperature resistant and water-resistant grease. Optionally, a grease replenishment port communicating with the outside of the pump body 1 can be provided.

[0049] As a deep well submersible pump, its working principle is as follows: the motor assembly 3 drives the central shaft 13 to rotate at high speed through the connection of the annular housing 8, which in turn drives the spiral blades 14 fixed on the central shaft 13 to rotate synchronously. The spiral blades 14 cover the entire flow channel. The downhole fluid enters from the inlet at the bottom of the pump body 1, gains energy by flowing through the spiral blades 14, and after the pressure increases, it is pressurized step by step (for multi-stage pumps) or directly transported through the flow channel inside the pump body 1, and finally discharged from the outlet of the upper end cover 101, realizing the function of lifting the deep well fluid to the surface. The magnetic levitation assembly 4 is a key structure set up to protect the auxiliary mechanical bearing 5 under this high-speed and high-pressure operating condition.

[0050] Additionally, the central shaft 13, the spiral blade 14, and the annular shell 8 are integrally machined. No specific limitations are made on the machining process here; the process can be 3D printing, casting, or other methods.

[0051] Specifically: Using a one-piece molding process can avoid leakage, extend service life, increase efficiency, and increase structural strength. (The friction boundary between the stator and rotor is placed outside the flow channel, unlike other pumps where the friction boundary is inside the flow channel. Impurities in the transported medium can have a significant impact on the friction boundary, such as wear or jamming. It is precisely because of the existence of this friction boundary inside the flow channel that other pumps will experience leakage, and as wear increases, the leakage will become greater and greater, and the service life will be extremely limited.)

[0052] In this embodiment, the motor assembly 3 includes, from the outside to the inside, a stator core and winding 301 fixed inside the middle housing 102, a Halbec array permanent magnet ring 302 arranged circumferentially outside the stator core and winding 301, a magnet protective cover 303 wrapped around the Halbec array permanent magnet ring 302, and a hollow motor shaft 304, wherein the central shaft 13 is fixedly inserted through the hollow motor shaft 304.

[0053] It should be noted that the motor rotor uses a Heilbeck array permanent magnet ring 302. This structure allows the magnetic field to be more concentrated on the air gap side, thereby achieving a higher air gap magnetic flux density in the same volume and improving the sinusoidal nature of the back EMF waveform, which is beneficial for the motor to achieve high-efficiency and low-torque pulsation operation. The magnet protective cover 303 is used to protect the permanent magnets from corrosion or physical damage in high-pressure fluid environments.

[0054] Preferably, the motor rotor can also use a common magnetic ring.

[0055] In this embodiment: the inner wall of the hollow motor shaft 304 is provided with annularly distributed docking grooves 6, and the outer wall of the annular housing 8 is provided with annularly distributed key 7, the key 7 and the docking grooves 6 cooperate with each other.

[0056] It should be noted that: through the cooperation of the docking slot 6 and the plug, the hollow shaft 304 of the motor can drive the integrated flow structure to move together when it rotates, so as to transport the medium to the outside.

[0057] In this embodiment, an annular magnetic shielding plate 9 fixed to the pump body 1 is provided between the bottom of the motor assembly 3 and the top of the magnetic levitation assembly 4. The annular magnetic shielding plate 9 is made of conductive but non-magnetic material.

[0058] It should be noted that the annular magnetic shielding plate 9, typically made of copper or aluminum alloy, primarily functions as magnetic shielding. It blocks the strong static magnetic field and stray magnetic field generated by the lower magnetic levitation component 4 from diffusing upwards, preventing these magnetic fields from interfering with the Halebeck array magnetic field distribution of the motor rotor, thus ensuring the stability and efficiency of the motor's electromagnetic performance. Its conductivity also facilitates the generation of eddy currents in the changing magnetic field, further consuming and suppressing interfering magnetic fields.

[0059] In this embodiment, a mechanical seal 10 is provided between the upper end cover 101 and the central shaft 13. The mechanical seal 10 is configured to withstand static hydraulic pressure of at least 20 MPa.

[0060] It should be noted that deep well environments have high static pressure, and this mechanical seal 10 is a crucial barrier to prevent high-pressure fluid from entering the motor through the gap in the central shaft 13. Setting its pressure-bearing capacity to no less than 20 MPa is a design value for common deep well operating conditions, ensuring reliable sealing at the rated well depth. This seal can be a tandem mechanical seal, a contact mechanical seal with a balancing structure, or a suitable non-contact sealing method to achieve long-term stable sealing at high speeds.

[0061] Preferably, the top and bottom of the mechanical seal 10 are also provided with auxiliary mechanical bearings 5 ​​to further provide axial bearing capacity to the central shaft 13 and improve stability.

[0062] In this embodiment, the inlet and outlet of the fluid channel 2 are also provided with a skeleton oil seal 11 to prevent impurities from entering the motor assembly 3.

[0063] It should be noted that the skeleton oil seal 11 is located on the fluid inlet path of the pump, serving as the first line of protection. Its main function is to prevent larger particles of mud, sand, rock debris, and other solid impurities carried in the conveyed medium from directly entering the internal cavity of the pump body 1, thereby reducing abrasive wear on subsequent precision components such as the mechanical seal. Together with the aforementioned high-pressure mechanical seal 10, it constitutes a multi-stage sealing system that is "anti-coarse sand and resistant to high pressure".

[0064] In this embodiment: the magnetic levitation component 4 includes at least two stages of magnetic force bearing units arranged in series along the central axis 13;

[0065] Each magnetic bearing unit includes a first annular magnet 401 fixed on the central shaft 13 and a second annular magnet 402 fixed on the pump body 1;

[0066] Within the same magnetic force bearing unit, the end faces of the first annular magnet 401 and the second annular magnet 402 that are axially opposite to each other are opposite magnetic poles, and the two are combined by magnetic attraction.

[0067] Between two adjacent magnetic bearing units, the end faces of the second annular magnet 402 in the upper level and the first annular magnet 401 in the lower level are axially opposite to each other and are magnetic poles of the same polarity. They form an axial suspension gap 12 through magnetic repulsion.

[0068] It should be noted that this structure constitutes a specific magnetic circuit of "intra-unit adsorption and inter-unit repulsion." The magnetic adsorption force within the unit establishes a stable force coupling between the central shaft 13 and the pump body 1. Meanwhile, the magnetic repulsion force between units creates an axial "pushing" effect between adjacent adsorption units, allowing multiple adsorption units connected in series to share the total downward axial force from the central shaft 13. Each adsorption unit transmits a portion of the axial force to the pump body 1 housing through its stationary magnet, ultimately dispersing it to the lower end cover 103. This design decomposes the concentrated large axial force into multiple smaller magnetic forces to bear the load.

[0069] In this embodiment, the magnetic levitation component 4 has three stages.

[0070] It should be noted that the use of a three-stage magnetic levitation unit is an optimal solution after comprehensively considering the axial load distribution effect, structural complexity, and axial space occupation. The three-stage design can provide sufficient magnetic load-bearing stages and redundancy within a reasonable axial length, ensuring a more uniform and stable distribution of axial force. If the number of stages is too small, the load-bearing capacity of a single stage will be too large; if the number of stages is too large, the structure will be lengthy, requiring higher precision in machining and assembly.

[0071] In this embodiment: In the magnetic bearing unit, the first annular magnet 401 and the second annular magnet 402 are in contact under the action of axial magnetic attraction.

[0072] It should be noted that the magnetic levitation component 4 of this invention is designed to always be in a "compressed, mutually repulsive levitation state". Specifically, the magnetic repulsion force between adjacent units (i.e., the repulsive force at the axial levitation gap 12) of the entire assembly, composed of magnetic force-bearing units connected in series at various levels, is preset to be greater than or equal to the maximum reverse axial load generated by the pump group in the entire operating range (including stationary, startup, rated operation, and overload). Therefore, under any operating state, the axial levitation gap 12 between adjacent units always exists and is dynamically maintained, and the small working gap between the first annular magnet 401 and the second annular magnet 402, maintained by the magnetic attraction force within the unit, also remains stable and will not come into contact. This "always levitation" design means that the load-bearing and buffering functions of the magnetic levitation component 4 are entirely achieved by non-contact magnetic field force, and its load-bearing capacity is determined by the magnetic circuit design itself, and is independent of changes in operating parameters such as speed and load, thus providing a more stable, more reliable, and zero-mechanical-wear-resistant axial force-bearing solution. The magnetic repulsion between units and the magnetic attraction within units together form a magnetic spring system with designable stiffness, ensuring the smooth transmission and distribution of axial loads among multi-level load-bearing units.

[0073] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A magnetically levitated high-speed internal lift pump for deep well mining, characterized in that, include: Pump body (1), the pump body (1) is composed of a detachable upper end cover (101), a middle section shell (102) and a lower end cover (103) from top to bottom along the axial direction, and the pump body (1) is provided with a through fluid channel (2). An integrated flow structure is provided in the fluid channel (2), which includes a vertical central shaft (13), spiral blades (14) spirally distributed on the central shaft (13), and an annular shell (8) placed outside the spiral blades (14). The motor assembly (3) is housed within the middle housing (102) and is used to drive the integrated flow structure to rotate in order to increase the fluid pressure; A magnetic levitation assembly (4) is disposed between the motor assembly (3) and the lower end cover (103). The magnetic levitation assembly (4) includes a rotating magnet assembly fixed on the annular housing (8) and a stationary magnet assembly fixed on the pump body (1). The rotating magnet assembly and the stationary magnet assembly interact through magnetic fields to jointly bear the main axial load acting on the integrated flow structure, and distribute the axial load to the pump body (1); and An auxiliary mechanical bearing (5) is disposed below the magnetic levitation assembly (4) and mounted on the middle housing (102) to provide radial support for the central shaft (13).

2. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 1, characterized in that, The motor assembly (3) includes, from the outside to the inside: a stator core and winding (301) fixed inside the middle housing (102), a Halbec array permanent magnet ring (302) arranged circumferentially outside the stator core and winding (301), a magnet protective cover (303) wrapped around the Halbec array permanent magnet ring (302), and a motor hollow shaft (304), wherein the central shaft (13) is fixedly inserted through the motor hollow shaft (304).

3. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 2, characterized in that, The inner wall of the hollow shaft (304) of the motor is provided with annularly distributed docking grooves (6), and the outer wall of the annular housing (8) is provided with annularly distributed key (7), and the key (7) cooperates with the docking grooves (6).

4. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 1, characterized in that, Between the bottom of the motor assembly (3) and the top of the magnetic levitation assembly (4), there is an annular magnetic shield (9) fixed to the pump body (1), the annular magnetic shield (9) being made of conductive but non-magnetic material.

5. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 1, characterized in that, A mechanical seal (10) is provided between the upper end cover (101) and the central shaft (13), the mechanical seal (10) being configured to withstand a static hydraulic pressure of at least 20 MPa.

6. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 1, characterized in that, The fluid channel (2) is also provided with a skeleton oil seal (11) at the inlet and outlet to prevent impurities from entering the motor assembly (3).

7. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 1, characterized in that, The magnetic levitation assembly (4) includes at least two stages of magnetic bearing units arranged in series along the central axis (13). Each magnetic bearing unit includes a first annular magnet (401) fixed on the central shaft (13) and a second annular magnet (402) fixed on the pump body (1). Within the same magnetic force bearing unit, the end faces of the first annular magnet (401) and the second annular magnet (402) that are axially opposite to each other are opposite magnetic poles, and the two are combined by magnetic attraction. Between two adjacent magnetic bearing units, the end faces of the second annular magnet (402) located in the upper level and the first annular magnet (401) located in the lower level are axially opposite to each other and are magnetic poles of the same polarity. An axial suspension gap (12) is formed between them through magnetic repulsion.

8. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 7, characterized in that, The magnetic levitation component (4) has three stages.

9. The magnetic levitation high-speed internal lift pump for deep well mining according to claim 8, characterized in that, In the magnetic bearing unit, the first annular magnet (401) and the second annular magnet (402) are in contact under the action of axial magnetic attraction.

Images