Search

CN-122014636-A - Magnetic suspension high-speed inner lift pump for deep well exploitation

CN122014636ACN 122014636 ACN122014636 ACN 122014636ACN-122014636-A

Abstract

The invention discloses a magnetic suspension high-speed internal lift pump for deep well exploitation, which relates to the technical field of fluid machinery and comprises a pump body, an integrated overflow structure and a motor assembly, wherein the pump body consists of an upper end cover, a middle section shell and a lower end cover which are detachably connected from top to bottom along the axial direction, a through fluid channel is arranged in the pump body, the integrated overflow structure is arranged in the fluid channel and comprises a vertical central shaft, spiral blades spirally distributed on the central shaft and an annular shell arranged outside the spiral blades, and the motor assembly is accommodated in the middle section shell and used for driving the integrated overflow structure to rotate so as to improve the fluid pressure. The invention actively shares the main axial load borne by the central shaft through the magnetic suspension component, effectively improves the stress working condition of the bottom auxiliary mechanical bearing, thereby being beneficial to prolonging the service life of the bearing and the pump body in the deep well high-pressure and high-impurity environment and improving the operation reliability.

Inventors

  • NIE MINGRUI

Assignees

  • 聂明锐

Dates

Publication Date
20260512
Application Date
20260314

Claims (9)

  1. 1. A magnetic suspension high-speed internal lift pump for deep well exploitation, its characterized in that includes: The pump body (1), the pump body (1) is formed by an upper end cover (101), a middle section shell (102) and a lower end cover (103) which are detachably connected from top to bottom along the axial direction, and a penetrating fluid channel (2) is arranged in the pump body (1); The integrated overflow structure is arranged in the fluid channel (2) and comprises a vertical central shaft (13), spiral blades (14) spirally distributed on the central shaft (13) and an annular shell (8) arranged outside the spiral blades (14); The motor assembly (3) is accommodated in the middle section shell (102) and is used for driving the integrated overflow structure to rotate so as to increase the fluid pressure; The magnetic suspension assembly (4) is arranged between the motor assembly (3) and the lower end cover (103), and the magnetic suspension assembly (4) comprises a rotary magnet group fixed on the annular shell (8) and a static magnet group fixed on the pump body (1); wherein the rotating magnet assembly and the stationary magnet assembly share a primary axial load acting on the integrated flow-through structure through magnetic field interaction and distribute and transfer the axial load to the pump body (1), and And the auxiliary mechanical bearing (5) is arranged below the magnetic suspension assembly (4) and is arranged on the middle section shell (102) and used for providing radial support for the central shaft (13).
  2. 2. The magnetic levitation high-speed internal lift pump for deep well exploitation according to claim 1, wherein the motor assembly (3) sequentially comprises a stator core and a winding (301) fixed in the middle section shell (102), a halbach array permanent magnet ring (302) circumferentially arranged outside the stator core and the winding (301), a magnetic steel protection cover (303) wrapped outside the halbach array permanent magnet ring (302), and a motor hollow shaft (304), wherein the central shaft (13) is fixedly penetrated through the motor hollow shaft (304).
  3. 3. The magnetic suspension high-speed internal lift pump for deep well exploitation according to claim 2, wherein the inner wall of the motor hollow shaft (304) is provided with annularly distributed butting grooves (6), the outer wall of the annular shell (8) is provided with annularly distributed inserting keys (7), and the inserting keys (7) are mutually matched with the butting grooves (6).
  4. 4. Magnetic levitation high-speed inner lift pump for deep well exploitation according to claim 1, characterized in that between the bottom of the motor assembly (3) and the top of the magnetic levitation assembly (4) an annular magnetic separator plate (9) is provided, fixed on the pump body (1), the annular magnetic separator plate (9) being made of an electrically and magnetically conductive material.
  5. 5. A magnetically levitated high-speed jack-up pump for deep well exploitation according to claim 1, characterized in that a mechanical seal (10) is arranged between the upper end cap (101) and the central shaft (13), the mechanical seal (10) being configured to withstand a hydrostatic pressure of at least 20 MPa.
  6. 6. The magnetic suspension high-speed internal lift pump for deep well exploitation according to claim 1, wherein the inlet and outlet of the fluid channel (2) is further provided with a framework oil seal (11) for preventing impurities from entering the interior of the motor assembly (3).
  7. 7. A magnetically levitated high-speed jack-up pump for deep well exploitation according to claim 1, characterized in that the magnetically levitated assembly (4) comprises at least two stages of magnetic force carrying units arranged in series along the axial direction of the central shaft (13); Each stage of the magnetic force bearing unit comprises a first annular magnet (401) fixed on the central shaft (13) and a second annular magnet (402) fixed on the pump body (1); In the same magnetic bearing unit, the end surfaces of the first annular magnet (401) and the second annular magnet (402) which are axially opposite to each other are opposite magnetic poles, and the first annular magnet and the second annular magnet are combined through magnetic attraction; Between two adjacent magnetic bearing units, the end faces of the second annular magnet (402) positioned at the upper stage and the first annular magnet (401) positioned at the lower stage, which are axially opposite to each other, are like magnetic poles, and an axial suspension gap (12) is formed between the two magnetic bearing units through the action of magnetic repulsive force.
  8. 8. The magnetically levitated high-speed internal lift pump for deep well exploitation according to claim 7, characterized in that the number of stages of the magnetically levitated assembly (4) is three.
  9. 9. The magnetic levitation high-speed inner lift pump for deep well exploitation according to claim 8, wherein in the magnetic force bearing unit, the first annular magnet (401) and the second annular magnet (402) are in contact state under the action of axial magnetic attraction force.

Description

Magnetic suspension high-speed inner lift pump for deep well exploitation Technical Field The invention relates to the technical field of fluid machinery, in particular to a magnetic suspension high-speed internal lift pump for deep well exploitation. Background Deep well extraction, such as extraction of resources like oil, geothermal, mineral water, etc., typically requires lifting fluids from the subsurface of hundreds to thousands of meters to the surface. In this application scenario, a submersible pump or an internal lift pump is the core transport device. In the prior art, a multistage centrifugal pump structure is generally adopted, and a driving motor is often arranged at the middle section or the lower part of a pump body and is connected with an impeller through a long shaft. In order to bear huge axial water thrust and rotor dead weight, a plurality of mechanical bearings (such as angular contact ball bearings or sliding bearings) are usually arranged in the pump body and are used as central shaft supports. The motor type is mainly an asynchronous induction motor or a common permanent magnet synchronous motor, and the rotating speed is adjusted through a frequency converter so as to adapt to different lift and flow requirements. In the aspect of sealing, a packing seal, a mechanical seal or a combined seal is adopted at the shaft extension part so as to cope with the underground high-pressure fluid environment. However, under the severe working condition of deep well exploitation, the traditional structure is assembled by a plurality of independent impellers, guide vanes and a shell cavity through a flow passage, has numerous joints and gaps, cannot form an absolute continuous sealing cavity, causes internal volume loss when the pump operates, and reduces volumetric efficiency. Secondly, the core mechanism relies on a precise "stator and rotor" clearance fit (i.e., radial clearance between the impeller and vanes) that is directly exposed to the high-velocity flowing sand-containing high-pressure well fluid. Solid impurities in the conveying medium easily enter the gap, severe abrasive particle abrasion is caused on the surfaces of the impeller and the guide vane, the gap is increased, leakage is increased, the pump efficiency is rapidly attenuated, and even the rotating part is blocked due to particle clamping stagnation in severe cases, so that catastrophic mechanical faults are caused. In addition, to drive the multi-stage impeller, conventional pumps must employ an elongated drive shaft and a plurality of intermediate bearings, which are mechanically complex, axially long and heavy. This not only increases the difficulty and cost of downhole installation, but also reduces the overall energy efficiency of the system due to mechanical losses on the drive train. Meanwhile, as with all deep-well pumps, the bearing system still needs to bear huge axial water thrust and rotor dead weight generated by the multistage impellers. Under the conditions of continuous high load and severe lubrication environment, the traditional mechanical bearing is extremely easy to generate early wear and fatigue failure, and becomes another key short plate for limiting the service life of the pump. Once the bearing or the overcurrent component is invalid in the deep well, all pump columns need to be lifted out for replacement, the operation period is long, the cost is extremely high, and the exploitation continuity and the economic benefit are seriously affected. Disclosure of Invention The invention aims to provide a magnetic suspension high-speed internal lift pump for deep well exploitation, which solves the problems of serious internal leakage, susceptibility to impurities in a conveying medium, complex mechanical structure, low efficiency, short service life of a mechanical bearing under huge axial load and the like caused by structural design limitation in the prior art. In order to achieve the aim, the invention provides the technical scheme that the magnetic suspension high-speed internal lift pump for deep well exploitation comprises a pump body, wherein the pump body consists of an upper end cover, a middle section shell and a lower end cover which are detachably connected from top to bottom along the axial direction, and a penetrating fluid channel is arranged in the pump body; The integrated overflow structure is arranged in the fluid channel and comprises a vertical central shaft, spiral blades spirally distributed on the central shaft and an annular shell arranged outside the spiral blades; The motor component is accommodated in the middle section shell and is used for driving the integrated overflow structure to rotate so as to improve the fluid pressure; The magnetic suspension assembly is arranged between the motor assembly and the lower end cover and comprises a rotary magnet group fixed on the annular shell and a static magnet group fixed on the pump body; Wherein the rotary magnet group and the stat