CN113612348A

CN113612348A - Submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor

Info

Publication number: CN113612348A
Application number: CN202111167733.0A
Authority: CN
Inventors: 赵立海; 钱加强
Original assignee: Dongying Fengruntong Technology Development Co ltd
Current assignee: Dongying Fengruntong Technology Development Co ltd
Priority date: 2021-10-08
Filing date: 2021-10-08
Publication date: 2021-11-05
Anticipated expiration: 2041-10-08
Also published as: CN113612348B

Abstract

The invention provides an oil-submersible screw pump based on an ultra-low speed multi-rotor permanent magnet oil-submersible motor, and relates to the technical field of oil well mechanical oil extraction equipment. This latent oil screw pump, including latent oily motor of permanent magnetism, protector joint and crossover sub, the one end of integral key shaft is provided with the main shaft, the outside fixedly connected with boss of integral key shaft, the inboard of connector is provided with the mounting groove, all be provided with the ball in the middle part lateral wall of mounting groove and the upper and lower both sides wall, the outside at the boss is connected in the outside of ball, and the latent oily motor of permanent magnetism includes motor joint subassembly, electric motor rotor, rights bearing and motor stator, and a permanent magnet is total 22 utmost points, has fan-shaped open slot, and the sensor in the pit is connected with the converter, and the one end of thrust disc is provided with thrust bearing, reduces the load of rights bearing, and the system need not to use the speed reducer, has improved the reliability of system, has higher starting torque, reduces system current and unit calorific capacity.

Description

Submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor

Technical Field

The invention relates to the technical field of oil well mechanical oil extraction equipment, in particular to an oil-submersible screw pump based on an ultra-low speed multi-rotor permanent magnet oil-submersible motor.

Background

Oil production equipment adopted at home and abroad mainly comprises two types of rod oil production equipment and rodless oil production equipment, and the rod oil production equipment generally has the following problems: (1) the energy utilization efficiency is low, the average efficiency of the rod pumping system is less than 20%, the oil extraction system is the largest production and power utilization system of the oil field, the annual power consumption of the oil extraction system accounts for about 56% of the total power consumption of the oil field, about one third of the production cost of the oil field is power consumption, the power consumption of the oil extraction equipment accounts for about 30% of the total power consumption of the oil extraction, and huge energy waste exists; (2) the oil recovery rate is low, and for high water-containing wells and heavy oil wells, the conventional ground driving oil pumping unit cannot carry out conventional exploitation due to high operation cost, so that a great amount of oil resources are wasted; (3) the volume is heavy, the occupied area is large, the working noise is large, some oil extraction equipment is positioned in urban residential areas, the land waste is caused, and the noise influences the work and life of residents; (4) it is not suitable for inclined wells, horizontal wells, etc. Compared with the most commonly used rod-type oil extraction equipment, namely a beam pumping unit, the direct-drive submersible screw pump rodless oil extraction equipment can save 70% of electricity, has high energy utilization efficiency and is internationally recognized as the most promising oil extraction equipment. However, because of the huge technical problems (the reducer is required to be adopted between the motor and the screw pump for reducing the speed, the output torque of the reducer often reaches 600Nm, and the existing reducer cannot reliably work for a long time in the space with the diameter of the pump body of only 100 mm at present), the direct-drive submersible screw pump rodless oil production equipment is not popularized and applied at present. According to the records of related data, the American Centrilift-Hughes company designs and produces an ESPCP system in 2002, a submersible motor is suitable for being matched with a special 9:1 gear reducer, and a thrust bearing adopts zirconia ceramics. In 2004, the radar company in the united states and one company in canada collaborate to research and develop an oil-submersible screw pump oil production system, a speed reducer structure is also adopted, and the speed reduction ratio is 16: 1 and 4: 1. Other countries such as russia and canada also have the submersible screw pump with the reducer structure developed by well-known companies in the industry, and are limited by domestic materials and the like.

The problems existing in the prior art are as follows: the speed reduction must be carried out by adopting a speed reducer between the motor and the screw pump, and the existing speed reducer cannot reliably work in a pump body for a long time at present, so that direct-drive submersible screw pump rodless oil production equipment is not popularized and applied at present.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an oil-submersible screw pump based on an ultra-low-speed multi-rotor permanent magnet oil-submersible motor, and solves the problem that the prior speed reducer cannot reliably work in a pump body for a long time, so that the direct-drive oil-submersible screw pump rodless oil extraction equipment is not high in practicability.

In order to achieve the purpose, the invention is realized by the following technical scheme: latent oily screw pump based on latent oily motor of super low-speed many rotors permanent magnetism, including latent oily motor of permanent magnetism, protector joint and crossover sub, connector fixed connection is passed through to the one end that the protector connects in the one end of crossover sub, the inside of crossover sub is provided with the flexbile shaft, the one end fixedly connected with integral key shaft of flexbile shaft, the one end of integral key shaft is provided with the main shaft, the outside fixedly connected with boss of integral key shaft, the inboard of connector is provided with the mounting groove, all be provided with the ball in the middle part lateral wall of mounting groove and the upper and lower both sides wall, the outside at the boss is connected in the outside of ball, the output at latent oily motor of permanent magnetism is connected to the one end of main shaft.

Preferably, the permanent magnetism submersible motor includes motor joint subassembly, electric motor rotor, rights bearing and motor stator, the one end fixed connection of motor joint subassembly is in motor stator's one end, motor joint subassembly's other end fixedly connected with protecting cover, one side fixed connection of protecting cover is at the other end that the protector connects, motor joint subassembly's one end inboard is provided with the semi-ring, the one end fixedly connected with thrust disc of semi-ring, the one end of thrust disc is provided with thrust bearing, thrust bearing's one end fixed connection is in motor joint subassembly's one end, motor stator's inboard is connected in motor rotor's the outside through rights bearing, there is electric motor rotor one end through the coupling joint.

Preferably, the main shaft, the spline shaft and the motor rotor are hollow shafts and are communicated up and down, the outer side of the motor rotor sequentially penetrates through the protecting cover, the thrust bearing, the protecting sleeve, the centering bearing and the guide bearing, and a radial hole is formed in the centering bearing.

Preferably, the iron core of the permanent magnet submersible motor stator is 22 poles, the permanent magnet submersible motor stator is composed of stator punching sheets, fan-shaped open slots are formed in the stator punching sheets, a stator winding of the motor stator is in a Y connection method, double-layer short-distance windings are adopted, the motor rotor is of a sectional type multi-rotor structure, each section of the motor rotor is located through a righting bearing, non-magnetic-conducting materials are arranged between the motor rotors for isolation, oil-resistant and wear-resistant gaskets are arranged at two ends of the righting bearing, and electromagnetic wires of the permanent magnet submersible motor are polyether ether ketone resin electromagnetic wires.

Preferably, the permanent magnet submersible motor is connected with an underground sensor through a polytetrafluoroethylene flexible wire, and the underground sensor is connected with a frequency converter through an armored cable.

Preferably, arc-shaped grooves are formed in the side wall of the middle part of the mounting groove and in the upper side wall and the lower side wall of the mounting groove.

Preferably, the shell of motor stator is provided with PIP multiple ion nitriding layer, and the stator is overall structure design, and the stator shell increases surface hardness and corrosion resistance through PIP multiple ion nitriding treatment, satisfies the oil field and uses for a long time.

The invention provides a submersible screw pump based on an ultra-low speed multi-rotor permanent magnet submersible motor. The method has the following beneficial effects:

1. the permanent magnet has 22 poles in total, the permanent magnet is provided with a fan-shaped open slot, the stator winding of the motor stator is in a Y connection method, double-layer short-distance windings are adopted, the electromagnetic wire adopts a PEEK (polyether ether ketone) resin electromagnetic wire with high strength, high toughness and high temperature resistance, a speed reducer is not needed, the reliability of the system is improved, the permanent magnet submersible motor has higher starting torque, the efficiency of the system is improved, and the power loss is reduced.

2. The inner side of one end of the motor joint component is provided with the semi-ring, one end of the semi-ring is fixedly connected with the thrust disc, one end of the thrust disc is provided with the thrust bearing, and the whole structure is designed according to the flexible body so as to reduce the over-positioning problem caused by respective deformation of the stator and the rotor and reduce the load for righting the bearing.

3. The centralizing bearing is internally provided with the radial hole, oil flows out from the radial hole under the action of centrifugal force when the permanent magnet submersible motor rotates, the centralizing bearing is lubricated, the oil in the inner cavity of the motor has reasonable size circulation design, and the oil supply of each lubricated part is considered as well as cooling, so that the effective lubrication of the motor is ensured.

4. The screw pump is connected with the spline shaft through the flexible shaft, and further connected with the permanent magnet submersible motor rotor through the main shaft, the outer side of the spline shaft is fixedly connected with the boss, the side wall of the middle part of the mounting groove and the upper side wall and the lower side wall of the mounting groove are respectively provided with the ball, and the outer sides of the balls are connected with the outer side of the boss, so that the motor rotor is prevented from being broken under the action of axial force and radial force, and the service life of the permanent magnet submersible motor is prolonged.

Drawings

FIG. 1 is a schematic view of a rotor core and permanent magnets of the present invention;

FIG. 2 is a schematic view of the magnetic pole distribution of the present invention;

FIG. 3 is a schematic view of a stator lamination of the present invention;

fig. 4 is a schematic view of a permanent magnet submersible motor of the present invention;

fig. 5 is a partial schematic view of a permanent magnet submersible motor of the present invention;

fig. 6 is a partial schematic view of a permanent magnet submersible motor of the present invention;

FIG. 7 is a schematic view of a connecting head according to the present invention;

fig. 8 is an enlarged view of fig. 7 at a.

Wherein, 1, a protective cover; 2. a coupling; 3. a half ring; 4. a thrust disc; 5. a thrust bearing; 6. a motor coupling assembly; 7. a sheath; 8. a motor stator; 9. a motor rotor; 10. righting the bearing; 11. a guide bearing; 12. a downhole sensor; 13. stator punching sheets; 14. a rotor core; 15. a permanent magnet; 16. a protector joint; 17. a connector; 18. a boss; 19. a ball bearing; 20. a spline shaft; 21. a crossover sub; 22. a flexible shaft; 23. mounting grooves; 24. a main shaft.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example (b):

as shown in fig. 1-8, an embodiment of the present invention provides an oil-submersible screw pump based on an ultra-low speed multi-rotor permanent magnet oil-submersible motor, including a permanent magnet oil-submersible motor, a protector joint 16 and an adapter 21, wherein one end of the protector joint 16 is fixedly connected to one end of the adapter 21 through a connector 17, a flexible shaft 22 is arranged inside the adapter 21, one end of the flexible shaft 22 is fixedly connected to a spline shaft 20, one end of the spline shaft 20 is provided with a main shaft 24, the screw pump is connected to the spline shaft 20 through the flexible shaft 22, and further connected to an output end motor rotor 9 of the permanent magnet oil-submersible motor through the main shaft 24, the outer side of the spline shaft 20 is fixedly connected to a boss 18, the inner side of the connector 17 is provided with an installation groove 23, balls 19 are arranged in the middle side wall and the upper and lower side walls of the installation groove 23, the outer side of the ball 19 is connected to the outer side of the boss 18, one end of the main shaft 24 is connected to the output end of the permanent magnet oil-submersible motor, namely through connecting main shaft 24 one end at the oily motor rotor 9 of permanent magnetism, during the use, connect flexbile shaft 22 with the screw pump, the oily motor rotor 9 of permanent magnetism can drive main shaft 24 and rotate, and then make integral key shaft 20 rotate, further can drive screw pump work through flexbile shaft 22, through the outside fixedly connected with boss 18 with integral key shaft 20, the inboard of connector 17 is provided with mounting groove 23, all be provided with the circular arc groove in the middle part lateral wall and the upper and lower both sides wall of mounting groove 23, be provided with ball 19 in the groove, the outside at boss 18 is connected in the outside of ball 19, realize reducing the axial force and the radial force that main shaft 24 and electronic rotor 9 received, motor rotor 9 can not break off, play firm effect to motor rotor axial and radial.

The iron core of the motor stator 8 is set to be 22 poles, the permanent magnet 15 has 22 poles in total and is provided with a fan-shaped open slot, the motor stator 8 consists of a stator punching sheet 13, the stator punching sheet 13 is internally provided with the fan-shaped open slot, a stator winding of the motor stator 8 adopts a Y connection method, double-layer short-distance windings are adopted, the magnetic potential of the double-layer short-distance windings is equal to the magnetic potential of two equivalent single-layer windings which are superposed in space, an electromagnetic wire of the permanent magnetic submersible motor adopts a polyether ether ketone resin electromagnetic wire, the electromagnetic wire adopts a PEEK (polyether ether ketone) resin electromagnetic wire with high strength, high toughness and high temperature resistance, a rotor iron core 14 of a motor rotor 9 adopts a sectional multi-rotor structure, and each section is positioned by a righting bearing 10, a non-magnetic-conductive material is arranged between each section of motor rotor 9 for isolation, and oil-resistant wear-resistant washers are arranged at two ends of the righting bearing 10, so that the righting bearing is ensured to rotate flexibly, and the influence of a permanent magnet on the righting bearing 10 is reduced.

The main shaft 24, the spline shaft 20 and the motor rotor 9 are hollow shafts and are communicated up and down, the outer side of the motor rotor 9 sequentially penetrates through the protecting cover 1, the thrust bearing 5, the sheath 7, the centering bearing 10 and the guide bearing 11, a radial hole is formed in the centering bearing 10, oil flows out from the radial hole under the action of centrifugal force when the permanent magnet submersible motor rotates, the centering bearing 10 is lubricated, the oil in a motor cavity is reasonable in size circulation design, the oil supply of each lubricating part is considered, effective lubrication of the oil is ensured, the permanent magnet submersible motor comprises a motor joint component 6, a motor rotor 9, the centering bearing 10 and a motor stator 8, one end of the motor joint component 6 is fixedly connected to one end of the motor stator 8, the other end of the motor joint component 6 is fixedly connected with the protecting cover 1, one side of the protecting cover 1 is fixedly connected to the other end of the protector joint 16, a semi-ring 3 is arranged on the inner side of one end of the motor joint component 6, half ring 3's one end fixedly connected with thrust disc 4, thrust disc 4's one end is provided with thrust bearing 5, thrust bearing 5's one end fixed connection is in motor joint subassembly 6's one end, it breaks to have guaranteed that electric motor rotor 9 does not receive the axial force effect, the life of the latent oil motor of extension permanent magnetism, motor stator 8's inboard is connected in electric motor rotor 9's the outside through righting bearing 10, shaft coupling 2 is passed through to main shaft 24's one end is connected with electric motor rotor 9, overall structure presses the design of flexible body, in order to reduce surely, the rotor warp the excessive location problem that brings separately, reduce the load of righting the bearing.

The permanent magnet submersible motor is connected with an underground sensor 12 through a polytetrafluoroethylene flexible wire, the underground sensor 12 is connected with a frequency converter through an armored cable, and a motor lead-out cable is of a wrapped structure, so that the operation is simple, and the sealing is reliable. The motor star point is connected with an underground sensor 12, the underground permanent magnet submersible motor sensor is supplied with power by means of three-phase unbalanced voltage of the motor star point, the underground sensor 12 senses the temperature of a motor winding, the vibration of an X axis and a Y axis, the pressure and the temperature of well liquid, detects the insulation of the motor on line, detects signals, transmits a ground frequency converter through a motor star point motor winding and a motor external armored cable by a power carrier technology, and realizes the intellectualization of the motor by vector control of the permanent magnet submersible motor.

The working principle of the invention is as follows: one end of the protector joint is fixedly connected with one end of the adapter joint through a connector, a flexible shaft is arranged inside the adapter joint, one end of the flexible shaft is fixedly connected with a spline shaft, one end of the spline shaft is provided with a main shaft, one end of the main shaft is connected with the output end of the permanent magnetic submersible motor, when in use, a screw pump is connected with a flexible shaft, a motor rotor of the permanent magnetic submersible motor can drive the main shaft to rotate, so that the spline shaft can rotate, the screw pump can be further driven to work through the flexible shaft, a boss is fixedly connected to the outer side of the spline shaft, the inner side of the connector is provided with a mounting groove, balls are arranged in the middle side wall and the upper and lower side walls of the mounting groove, the outer sides of the balls are connected to the outer side of the boss, the axial force and the radial force borne by the main shaft and the electronic rotor are reduced, the motor rotor is ensured not to be broken, and the service life of the permanent magnetic submersible motor is prolonged, the system can work reliably for a long time, the traditional electric submersible screw pump system usually adopts the submersible screw pump system of the traditional submersible motor matched with a speed reducer, the rotating speed of the submersible screw pump system runs between 50 and 300, the permanent magnetic direct-drive submersible screw pump and the submersible screw pump have similar configurations, the main difference is that the system does not use the speed reducer, the ultra-low speed 22-pole permanent magnetic motor is adopted, the permanent magnetic submersible motor is vector-controlled by a frequency converter to enable the pump speed of the screw pump to run between 50 and 300, the system does not need to use the speed reducer, the reliability of the system is improved, the permanent magnetic submersible motor has higher starting torque, the efficiency of the system is improved, meanwhile, the power loss is reduced, the current of the system and the heating value of a sucker rod of a unit are reduced, and the premature abrasion of the sucker rod/oil pipe caused by the limitation of depth or deviated well in the traditional driving system is avoided.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. Latent oily screw pump based on latent oily motor of ultra-low speed multi-rotor permanent magnetism, including latent oily motor of permanent magnetism, protector joint (16) and crossover sub (21), its characterized in that: connector (17) fixed connection is passed through in the one end of crossover sub (21) to the one end of protector joint (16), the inside of crossover sub (21) is provided with flexbile shaft (22), the one end fixedly connected with integral key shaft (20) of flexbile shaft (22), the one end of integral key shaft (20) is provided with main shaft (24), the outside fixedly connected with boss (18) of integral key shaft (20), the inboard of connector (17) is provided with mounting groove (23), all be provided with ball (19) in the middle part lateral wall and the upper and lower both sides wall of mounting groove (23), the outside at boss (18) is connected in the outside of ball (19), the output at permanent-magnet submersible motor is connected to the one end of main shaft (24).

2. The submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor of claim 1 characterized by: the permanent magnet submersible motor comprises a motor joint component (6), a motor rotor (9), a centering bearing (10) and a motor stator (8), wherein one end of the motor joint component (6) is fixedly connected with one end of the motor stator (8), the other end of the motor joint component (6) is fixedly connected with a protective cover (1), one side of the protective cover (1) is fixedly connected with the other end of a protector joint (16), a half ring (3) is arranged on the inner side of one end of the motor joint component (6), one end of the half ring (3) is fixedly connected with a thrust disc (4), one end of the thrust disc (4) is provided with a thrust bearing (5), one end of the thrust bearing (5) is fixedly connected into one end of the motor joint component (6), and the inner side of the motor stator (8) is connected to the outer side of the motor rotor (9) through the centering bearing (10), one end of the main shaft (24) is connected with a motor rotor (9) through a coupler (2).

3. The submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor of claim 1 characterized by: the main shaft (24), the spline shaft (20) and the motor rotor (9) are hollow shafts and are communicated up and down, the outer side of the motor rotor (9) sequentially penetrates through the protective cover (1), the thrust bearing (5), the protective sleeve (7), the centering bearing (10) and the guide bearing (11), and a radial hole is formed in the centering bearing (10).

4. The submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor of claim 1 characterized by: the iron core of motor stator (8) sets up to 22 utmost points, motor stator (8) comprise stator punching (13) and be provided with fan-shaped open slot in stator punching (13), the stator winding of motor stator (8) is Y connection, adopts double-deck short-distance winding, motor rotor (9) adopt the many rotor structure of sectional type and every section all fixes a position through righting bearing (10), every section all set up between motor rotor (9) and do not lead the magnetic material to keep apart, the both ends of righting bearing (10) all are provided with resistant oily wear-resisting packing ring, permanent magnetism submersible motor's electromagnetic wire adopts polyether ether ketone resin electromagnetic wire.

5. The submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor of claim 1 characterized by: the permanent magnet submersible motor is connected with an underground sensor (12) through a polytetrafluoroethylene flexible wire, and the underground sensor (12) is connected with a frequency converter through an armored cable.

6. The submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor of claim 1 characterized by: arc-shaped grooves are formed in the side wall of the middle part of the mounting groove (23) and the side walls of the upper side and the lower side.

7. The submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor of claim 1 characterized by: the shell of the motor stator (8) is provided with a PIP multi-element ion nitriding layer.

8. The submersible screw pump based on ultra-low speed multi-rotor permanent magnet submersible motor of claim 1 characterized by: the motor stator (8) comprises a permanent magnet (15), and the permanent magnet (15) is formed by bonding magnetic steel which can resist temperature of 180 ℃ through epoxy glue.