CN111769680B

CN111769680B - Radial magnetic circuit submersible linear motor

Info

Publication number: CN111769680B
Application number: CN202010582067.6A
Authority: CN
Inventors: 陈天为; 李勇
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-06-24
Filing date: 2020-06-24
Publication date: 2023-09-26
Anticipated expiration: 2040-06-24
Also published as: CN111769680A

Abstract

The application discloses a radial magnetic circuit submersible linear motor, which comprises a primary assembly and a secondary assembly which is matched with the primary assembly, wherein sealing systems for preventing water from entering are arranged on two sides of the primary assembly, a pressure balancing device is arranged between the secondary assembly and the sealing systems, and a lubrication cooling assembly for cooling and lubricating the motor is arranged in the secondary assembly. The application has the following beneficial effects: the radial magnetic circuit submersible linear motor can fully dissipate heat and prevent the motor from overheat and shutdown.

Description

Radial magnetic circuit submersible linear motor

Technical Field

The application relates to a radial magnetic circuit submersible linear motor.

Background

As most oil fields enter the middle and later stages of development successively, well conditions become more complex, requirements for oil stabilization, water control and energy conservation are continuously improved, and intelligent, efficient and low-loss oil extraction equipment becomes an important point for the development of petroleum machinery equipment industry. Therefore, various energy-saving power equipment such as an ultrahigh slip motor, a variable frequency speed regulating motor, a double-power motor, a motor voltage regulating device and the like are continuously developed and applied in an oil field, and the automation control level is correspondingly improved. The system efficiency of the linear motor is obviously improved after the linear motor replaces the rotary motor due to the excellent driving performance.

Linear motors have unique applications for downhole operation. The linear motor can be divided into a linear motor pumping unit and a linear motor oil extraction pump when working underground.

The linear motor pumping unit has a ground part, a middle part and a downhole pump as the pumping unit with a rod. The middle part is mainly a transmission part such as a sucker rod, the underground pump is a plunger pump, and the ground part mainly comprises a cable, a traction rope, a balance wheel, a bracket, a linear motor, a guide frame, a weight box, a sensor, a frequency converter control cabinet and the like. The support is fixed on the base, the motor secondary is fixed on the support, the fixed platform is supported by the support, and the balance wheel can be arranged on the balance wheel platform by using a single wheel or arranging a large wheel and a small wheel in parallel. The stator of the linear motor is fixed in the bracket and is formed by welding a steel plate and a section bar. The edge of the stator plate is provided with a limiting block for controlling the primary trend of the motor. The guide rail plays a guiding role and is used for protecting the motor. The lower part of the motor rotor is connected with a weight box which is used for increasing and decreasing the balance weight to adjust the balance of the whole machine. The traction rope adopts two steel wire ropes, one end of the traction rope is connected with the rope hanger, the other end of the traction rope is connected with the motor rotor, the traction rope respectively bypasses the pulleys on the rope hanger, and is connected with the motor rotor after changing the direction through the large wheel and the small wheel. The linear motor rotor is directly connected with the sucker rod through the flexible connecting piece, the steel wire rope and the guide wheel. The motion of the rotor is completely consistent with the up-and-down motion of the oil pump plunger, and the motor drives the oil pumping rod to move up and down through the traction rope to complete the oil pumping process.

The linear motor oil extraction pump mainly comprises a ground numerical control device, an underground magnetic driving plunger pump, a special cable and a liquid level monitor, wherein the underground magnetic driving plunger pump comprises a linear motor, a screen pipe, a plunger pump and the like. The plunger pump is positioned below the cylindrical linear motor, and the plunger pump and the cylindrical linear motor are connected with the connecting rod through the permanent magnet rotor. After the system is electrified, the linear motor rotor drives the plunger to reciprocate up and down, so that the purpose of lifting oil pumping is achieved, and meanwhile, the system is also provided with a downhole pressure and temperature sensor for monitoring the working pressure and temperature of the sinking position of the pump.

The axial magnetic field linear motor is generally provided with a magnetic isolation material in the middle, magnetic steel is arranged on the outer diameter of the magnetic isolation material, and a coil is wound on the magnetic isolation material to realize the generation of an axial magnetic field. The axial magnetic field linear motor can lead to deformation and cracking of magnetic steel when working underwater for a long time, and meanwhile, the middle part is made of a magnetism isolating material, so that the heat dissipation performance is poor, heat generated by the motor can not be discharged, and the motor is overheated and stopped.

Disclosure of Invention

The application aims to provide a radial magnetic circuit submersible linear motor. The radial magnetic circuit submersible linear motor can fully dissipate heat and prevent the motor from overheat and shutdown.

The application aims at realizing the following technical scheme:

the utility model provides a radial magnetic circuit dive linear motor, includes primary assembly and the secondary assembly of installation with primary assembly cooperation, primary assembly both sides are provided with the sealing system that is used for preventing into water, be provided with pressure balancing unit between secondary assembly and the sealing system, be provided with in the secondary assembly and be used for carrying out the lubricated cooling assembly of cooling lubrication to the motor.

By adopting the technical scheme, the traveling wave magnetic field of the primary assembly and the radial magnetic field of the secondary assembly are utilized to operate in design, so that the middle part is provided with the flow channel for oil extraction, and conditions are provided for heat dissipation. The middle part of the axial magnetic field linear motor is made of solid magnetism isolating materials, a runner cannot be arranged in the middle part, oil extraction is carried out on two sides, and therefore the diameter of a pipeline cannot bear a heat dissipation device. The linear motor designed by the application has enough space, the cooling and lubricating device is arranged in the middle part, so that a better heat dissipation effect is achieved, oil extraction from two sides is not needed, the design of an internal oil extraction pipeline is simpler, and the oil extraction efficiency is higher.

The application is further provided with: the primary assembly comprises a plurality of sections of iron cores, a plurality of installation cavities are formed in the inner sides of the sections of iron cores, a coil framework is arranged in each installation cavity, and a group of a plurality of coils are wound on the coil framework.

By adopting the technical scheme, the radial magnetic circuit linear motor provided by the application is less applied to the underground oil extraction history, and the reason is that the radial magnetic field is applied to the underground oil extraction history for many years, but more problems occur in the middle, so that the axial magnetic field is more commonly applied to the underground oil extraction. In the past, radial magnetic fields have been difficult to overcome the problem of insufficient oil extraction power and low oil extraction efficiency when applied downhole, and therefore, the application of axial magnetic fields belongs to a scheme commonly adopted by those skilled in the art. The present document proposes a new solution for overcoming this problem, aiming at the deficiency of the radial magnetic field. A plurality of coil bobbins are installed in the core, and coils are wound on the coil bobbins so that a traveling wave magnetic field is generated. After the traveling wave magnetic field is generated, the fixed radial magnetic field in the secondary assembly is matched to do work, square wave vibration caused by the operation of the axial magnetic field is effectively reduced, the service life of the parts is short, and meanwhile, the oil extraction efficiency can be effectively improved when the traveling wave magnetic field is matched to do work. The technical difficulty lies in that the axial magnetic field can be realized only by winding a plurality of coils in the axial direction, and the coils are required to be arranged at all positions of the radial magnetic field, so that the radial magnetic field covering the whole secondary assembly is generated, the service life of the equipment can be effectively prolonged, and meanwhile, the production efficiency can be ensured.

The application is further provided with: the iron core is characterized in that cross sealing rings are arranged on two sides of an inner hole of the iron core, notch insulating clamps are arranged at the coil leading-out positions, lacing wires are arranged between every two iron cores, and the iron cores at two ends are respectively an upper connecting iron core and a lower connecting iron core.

After the technical scheme is adopted, the problem of leakage of the radial magnetic field under specific working conditions is solved by the arrangement of the cross sealing ring. Because the radial magnetic field needs more coils, the problem of water leakage is easy to generate when the radial magnetic field works underground, in order to ensure the sealing efficiency, the cross sealing ring arranged in the application can ensure the sealing effect in all directions, and meanwhile, the cross sealing ring can ensure the stable installation of the sealing ring. The notch insulating clamp provided by the application can prevent the enameled wire and the iron core from being tightly supported by full load and overload to break down the wire, and reduce the occurrence rate of faults. Through the setting of lacing wire, connect a plurality of iron cores into the composition, carry out the modularization combination through single section is whole, realize the linear electric motor of different powers and satisfy the thrust requirement of different well conditions, the modularization combination makes the product serialization. The upper connecting iron core and the lower connecting iron core are used for connecting sliding bearings and other primary single sections, and the whole connection sequence and the installation convenience are guaranteed.

The application is further provided with: the secondary assembly comprises a base shaft, and base shaft connecting assemblies connected with other external pipes are arranged at two ends of the base shaft;

magnetic steel and magnetism isolating rings are arranged outside the base shaft; and a magnetic steel jacket is arranged outside the magnetic steel and the magnetism isolating ring.

The magnetic steel is provided with a plurality of magnetic poles which are arranged on the base shaft and are N, S series to form a radial magnetic field;

the magnetism isolating rings are arranged in a plurality, and each magnetism isolating ring is arranged between every two magnetic steels.

By adopting the technical scheme, compared with an axial magnetic field, the magnetic poles of the adjacent magnetized magnetic steels provided by the document are opposite and are arranged on the base shaft in N, S, N, S, N, S, N, S to form a radial magnetic circuit. The radial magnetic circuit is perpendicular to the axial magnetic field along the radial direction. The magnetism isolating rings are arranged between the adjacent magnetic steels and used for isolating the magnetic fields, so that the magnetic fields between the adjacent magnetic steels cannot be mutually mixed. Under the radial magnetic field, the magnetic field setting method can effectively reduce the magnetic tension, does not need a rotor to counteract the magnetic tension, reduces the maintenance work difficulty and prolongs the service life.

The application is further provided with: the base shaft connecting assembly comprises secondary connectors arranged at two ends of the base shaft, the two secondary connectors are respectively connected with a base shaft connecting rod and an upper connecting rod connector, and the upper connecting rod connector is in threaded connection with an upper connecting rod.

The application is further provided with: the lubricating and cooling assembly is arranged in the base shaft;

the lubrication cooling assembly comprises a lubrication oil pipe;

the lubricating oil pipe forms the internal circulation oil flow of circulation flow.

The lubrication cooling assembly comprises an oil pipe sealing ring;

the oil pipe sealing ring is arranged between the secondary joint and the lubricating oil pipe, and oil circulation is formed in the lubricating oil pipe.

After the technical scheme is adopted, the lubricating and cooling assembly is mainly used for dispersing heat generated by magnetic field acting in the base shaft and relative movement between components, and the oil liquid has higher melting point and higher specific heat capacity, so that the internal heat dissipation effect is better. Meanwhile, the lubricating oil pipe forms internal circulation flow, which is favorable for lubricating the base shaft and the connecting parts thereof and preventing severe abrasion. The oil pipe sealing ring is just arranged between the secondary joint and the lubricating oil pipe, so that oil can not enter the secondary joint along a gap between the base shaft and the secondary joint, the internal circulation flow of the oil is ensured, and meanwhile, the oil leakage is prevented. On the other hand, the mounting stability and positioning can be improved.

The application is further provided with: the sealing system comprises a sealing pipe, a flow channel is arranged in the middle of the sealing pipe, and a multistage sealing mechanism is arranged in the flow channel;

the multistage sealing mechanism comprises a plurality of sealing groups and sliding bearings arranged on two sides of the sealing groups, and a plurality of sealing grooves for installing sealing rings are formed at the joint of the sliding bearings and the sealing pipes.

Through adopting above-mentioned technical scheme, through multistage sealing mechanism, the effectual leakproofness that improves whole sealed tube prevents to appear the problem of intaking in each direction, has effectively reduced the sealed problem that leads to when working in the pit.

The application is further provided with: the sliding bearing comprises a first bearing and a second bearing, a guide block is arranged on one side of the first bearing in the sealing tube, and the sealing groove is arranged between the guide block and the first bearing, and between the sealing group and the first bearing.

After the technical scheme is adopted, one side of the guide block is an inlet section, and the inlet section is an oil extraction section. According to the flow volume formula, the guide block reduces the diameter of the inlet part, and the flow velocity is larger under the condition of the same unit volume, so that the oil extraction efficiency is improved. Meanwhile, the sealing groove is arranged between the guide block and the first bearing, and between the sealing group and the first bearing, so that the problem of tightness caused by the increase of the flow velocity is effectively prevented.

The application is further provided with: a breathing port screen is arranged between the guide block and the threaded connector, and a breathing port is arranged on the breathing port screen.

After the technical scheme is adopted, the breathing port screen mesh plays a role in filtering impurities in the conveying fluid.

The application is further provided with: the pressure balancing device comprises a valve body, a balancing hole pipe is arranged in the middle of the valve body, the balancing hole pipe is communicated with a differential pressure pipe, one section of the differential pressure pipe is provided with a screw for sealing installation, and a balancing valve core is slidably connected in the differential pressure pipe.

After the technical scheme is adopted, when the internal pressure is overlarge, the balance hole pipe increases the pressure to the differential pressure pipe, so that the balance valve core in the differential pressure pipe moves reversely, the internal volume is increased, and the differential pressure is balanced, and vice versa.

In summary, the present application has the following advantageous objects:

1. the radial magnetic circuit linear motor provided by the document has less application in underground oil extraction history, because the application of the radial magnetic field in underground oil extraction has been many years old, but more problems appear in the middle, so that the application of the axial magnetic field in underground oil extraction is more common. In the past, radial magnetic fields have been difficult to overcome the problem of insufficient oil extraction power and low oil extraction efficiency when applied downhole, and therefore, the application of axial magnetic fields belongs to a scheme commonly adopted by those skilled in the art. The present document proposes a new solution for overcoming this problem, aiming at the deficiency of the radial magnetic field. A plurality of coil bobbins are installed in the core, and coils are wound on the coil bobbins so that a traveling wave magnetic field is generated. After the traveling wave magnetic field is generated, the fixed radial magnetic field in the secondary assembly is matched to do work, square wave vibration caused by the operation of the axial magnetic field is effectively reduced, the service life of the parts is short, and meanwhile, the oil extraction efficiency can be effectively improved when the traveling wave magnetic field is matched to do work. The technical difficulty is that the axial magnetic field can be realized only by winding a group of a plurality of coils in the axial direction, and the coils are required to be arranged at all positions of the radial magnetic field, so that the radial magnetic field covering the whole secondary assembly is generated, the traveling wave magnetic field generated by the primary assembly and the radial magnetic field of the secondary assembly can effectively prolong the service life of equipment, and meanwhile, the production efficiency can be ensured;

2. the radial magnetic circuit formed by the radial magnetized magnetic steel provided by the document can effectively reduce magnetic leakage, the magnetic circuit approaches to a sine wave through the correction angle of the magnetic steel jacket, square wave vibration is reduced, and the service life is prolonged; the traveling wave magnetic field and the radial magnetic field are matched to operate, so that the oil extraction efficiency is improved;

3. the sealing system disclosed by the application is a necessary system required by the operation of the underground linear motor, mainly plays a good sealing effect, prevents fluid from entering a connecting gap of a sealing pipe, reduces internal corrosion and can improve oil extraction efficiency.

Drawings

FIG. 1 is a schematic diagram of the overall structure of an embodiment;

FIG. 2 is a schematic view of the structure of a primary single segment;

FIG. 3 is a cross-sectional view of a primary single segment;

FIG. 4 is a schematic view of a secondary assembly;

FIG. 5 is a schematic view of the structure of the upper sealing device;

FIG. 6 is a schematic view of the structure of the lower sealing device;

fig. 7 is a schematic structural view of the pressure balancing device.

Reference numerals: 1. primary assembly; 2. secondary assembly; 3. a sealing system; 4. a pressure balancing device; 1-a, upper connecting iron core; 2-a, a coil; 3-a, a coil skeleton; 4-a, iron core; 5-a, a cross sealing ring; 6-a, slot insulating clips; 7-a, connecting the iron cores at the lower part; 8-a, lacing wires; 9-a, installing a cavity; 1-b, a base shaft; 2-b, a base shaft connecting assembly; 21-b, secondary linker; 22-b, a base shaft connecting rod; 23-b, upper link joint; 24-b, upper connecting rod; 3-c, lubricating and cooling the assembly; 31-c, a lubricating oil pipe; 32-c, an oil pipe sealing ring; 4-b, radial magnetic field assembly; 41-b, magnetic steel; 42-b, magnetism isolating rings; 43-b, a magnetic steel jacket; 1-d, an upper sealing device; 2-d, a lower sealing device; 3-1-d, and a sealing tube is arranged on the upper part; 3-2-d, lower sealing tube; 4-d, a runner; 5-d, a multistage sealing mechanism; 51-d, sealing group; 52-d, sliding bearings; 521-d, bearing one; 522-d, bearing two; 53-d, sealing the groove; 6-d, pressing the cap by the screw thread; 7-d, a breath port screen; 8-d, a respiration port; 9-d, a threaded interface; 10-d, a guide block; 1-e, valve body; 2-e, a differential pressure tube; 3-e, balancing the valve core; 4-e, screws; 5-e, balancing the hole pipe.

Detailed Description

The present application will be described in further detail with reference to the accompanying drawings.

The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.

As shown in fig. 1, the radial magnetic circuit submersible linear motor comprises a primary assembly 1 and a secondary assembly 2 which is matched with the primary assembly 1, wherein sealing systems 3 for preventing water from entering are arranged on two sides of the primary assembly 1, a pressure balancing device 4 is arranged between the secondary assembly 2 and the sealing systems 3, and a lubrication cooling assembly 3-c for cooling and lubricating the motor is arranged in the secondary assembly 2.

1. Primary Assembly 1

As shown in fig. 2-3, the primary assembly 1 is made up of a plurality of individual segments, only one of which need be described, the primary assembly 1 individual segments comprising a multi-segment core 4-a. The iron cores 4-a at the two ends are an upper connecting iron core 4-a1-a and a lower connecting iron core 7-a4-a. The upper connecting iron core 4-a1-a and the lower connecting iron core 7-a4-a are used for connecting other primary single-section assemblies, so that the primary single-section assembly is convenient.

The inner sides of the multi-section iron cores 4-a are provided with a plurality of mounting cavities 9-a. A coil former 3-a is arranged in the mounting cavity 9-a. A plurality of coils 2-a are wound on each coil bobbin 3-a.

The present document proposes a new solution for overcoming this problem, aiming at the deficiencies of the existing radial magnetic fields. A plurality of bobbins 3-a are installed inside the core 4-a, and the coils 2-a are wound on the bobbins 3-a so that a radial magnetic field is generated. The radial magnetic field in the secondary assembly 2 is simultaneously utilized to perform cooperation work after the traveling wave magnetic field is generated, so that the service life of parts caused by square wave vibration generated by axial magnetic field operation is effectively reduced, and meanwhile, the oil extraction efficiency can be effectively improved during cooperation work. The technical difficulty is that the axial magnetic field can be realized only by winding a group of a plurality of coils 2-a in the axial direction, and the coils 2-a are required to be arranged at all positions of the radial magnetic field, so that the radial magnetic field covering the whole secondary assembly 2 is generated, the service life of equipment can be effectively prolonged, and meanwhile, the production efficiency can be ensured.

Optimally, a notch insulating clamp 6-a is arranged at the leading-out position of the coil 2-a, so that electromagnetic interference phenomenon is prevented, and equipment failure rate is reduced.

Preferably, tie bars 8-a are arranged between every two iron cores 4-a. The arrangement of the lacing wire 8-a enables the whole radial magnetic field to be in an integral state, and improves the effect of integral combined secondary work.

Optimally, both sides of the inner hole of the iron core 4-a are provided with cross sealing rings 5-a. Because the number of coils 2-a needed by the radial magnetic field is large, water leakage is easy to occur during underground working, in order to ensure the sealing efficiency, the cross sealing ring 5-a arranged in the application can ensure the sealing effect in all directions, and meanwhile, the cross sealing ring 5-a can ensure the stable installation of the sealing ring.

2. Secondary assembly 2

As shown in fig. 4, the secondary assembly 2 comprises a base shaft 1-b, on which base shaft 1-b a base shaft 1-b connection assembly, a lubrication cooling assembly 3-c, a radial magnetic field assembly 4-b are arranged.

Base shaft 1-b connection assembly: comprising secondary joints 21-b arranged at both ends of the base shaft 1-b. The two secondary joints 21-b connect the base shaft 1-b links with the upper link joints 23-b, respectively. The upper link joint 23-b is connected with an upper link 24-b. The secondary joint 21-b is mainly used for connecting other pipe fittings and plays a role of connecting pipelines.

Radial magnetic field assembly 4-b: comprises magnetic steel 41-b and a magnetism isolating ring 42-b which are arranged in a base shaft 1-b.

The magnetic steel 41-b is provided with a plurality of magnetic poles, wherein the magnetic poles of the magnetic steel 41-b arranged on the base shaft 1-b are N, S series, namely an arrangement structure of N, S, N, S, N, S, N.

The number of magnetism isolating rings 42-b is plural, and each magnetism isolating ring 42-b is arranged between every two magnetic steels 41-b.

The magnetic steel 41-b and the magnetism isolating ring 42-b are externally provided with the magnetic steel jacket 43-b, so that the abrasion and demagnetization of the magnetic steel 41-b are prevented, and the service life of the magnetic steel 41-b is prolonged.

When the external primary three-phase winding U, V, W applies three-phase sinusoidal voltage, the primary iron core 4-a generates periodic alternating magnetic field and secondary fixed radial magnetic field to do coupling work, the radial travelling magnetic field is generated between the primary and secondary to realize relative linear motion, when the three-phase sinusoidal voltage time sequence is changed, the running direction of the linear motor is changed, when the primary is fixed, the secondary is a moving part, and otherwise, the secondary is fixed, and the primary is a moving part.

3. Lubrication cooling assembly 3-c

The lubrication cooling assembly 3-c comprises a lubrication pipe 31-c arranged in the base shaft 1-b, the lubrication pipe 31-c forms internal circulation oil fluid flowing circularly around the base shaft 1-b, and distributes heat accumulated on the base shaft 1-b, and simultaneously plays a lubrication role to prevent abrasion of the base shaft 1-b during operation. The lubrication and cooling assembly 3-c further includes an oil pipe seal ring 32-c. The oil pipe seal ring 32-c is disposed between the secondary joint 21-b and the oil pipe 31-c such that an oil circulation is formed in the oil pipe 31-c. The oil pipe seal ring 32-c can prevent oil from flowing into the connection gap of the secondary joint 21-b, so that the oil forms an internal circulation and is continuously lubricated and cooled.

4. Sealing system 3

As shown in fig. 5-6, the sealing system 3 comprises an upper sealing device 1-d and a lower sealing device 2-d.

The upper sealing device 1-d comprises an upper sealing tube 3-1-d. The middle part of the upper sealing tube 3-1-d is provided with a flow passage 4-d, and the sealing tube is internally provided with a multistage sealing mechanism 5-d for preventing water leakage in all directions.

The multi-stage sealing mechanism 5-d includes:

1. a plurality of seal groups 51-d;

2. sliding bearings 52-d provided on both sides of the outer edge seal group 51-d.

For a plurality of seal groups 51-d:

the sliding bearings 52-d on both sides can be divided into a first 521-d bearing and a second 522-d bearing.

The upper sealing tube 3-1-d is provided with a guide block 10-d at one side of the bearing one 521-d. A seal groove 53-d is provided between the guide block 10-d and the bearing one 521-d. Meanwhile, the same seal groove 53-d is provided between the bearing one 521-d and the seal group 51-d. And a sealing ring is arranged in the sealing groove 53-d, so that the tightness of the sealing groove is ensured.

A threaded press cap 6-d is arranged on one side of the second bearing 522-d. The screw press cap 6-d is used to fasten the seal group 51-d and the slide bearing 52-d.

Optimally, threaded interfaces 9-d are arranged on two sides of the upper sealing tube 3-1-d. The threaded connection 9-d is used for screwing other pipes.

The lower sealing device 2-d comprises a lower sealing tube 3-2-d. The middle part of the lower sealing tube 3-2-d is provided with a flow passage 4-d, and the sealing tube is internally provided with a multistage sealing mechanism 5-d for preventing water leakage in all directions.

The multi-stage sealing mechanism 5-d includes:

1. a plurality of seal groups 51-d;

For a plurality of seal groups 51-d:

The lower sealing tube 3-2-d is provided with a guide block 10-d at one side of the bearing one 521-d. A seal groove 53-d is provided between the guide block 10-d and the bearing one 521-d. Meanwhile, the same seal groove 53-d is provided between the bearing one 521-d and the seal group 51-d. And a sealing ring is arranged in the sealing groove 53-d, so that the tightness of the sealing groove is ensured.

Optimally, both sides of the lower sealing tube 3-2-d are provided with threaded interfaces 9-d. The threaded connection 9-d is used for screwing other pipes.

In respect of the difference from the upper sealing device 1-d, the lower sealing tube 3-2-d is provided with a breath-opening screen 7-d between the guide block and the threaded interface 9-d. The outer circle part of the breathing hole screen 7-d is provided with a breathing hole 8-d.

For the embodiment and the embodiment, the lower sealing pipe 3-2-d-is arranged at a position close to the wellhead, so that the arranged breathing port screen 7-d can play a good role in filtering effect and balancing pressure difference, and the problem of tightness is not worried. While the lower sealing tube 3-2-d-is arranged at a position near the bottom of the well, so that there is a higher demand for its tightness. In the actual production process, the environment variation of the upper sealing tube 3-1-d-is more complex, and the sealing degree level of the upper sealing tube can be improved according to the actual situation.

5. Pressure balancing device 4

As shown in fig. 7, the pressure balancing device 4 comprises a valve body 1-e, a balancing hole pipe 5-e is arranged in the middle of the valve body 1-e, the balancing hole pipe 5-e is communicated with a differential pressure pipe 2-e, one section of the differential pressure pipe 2-e is provided with a screw 4-e for sealing installation, and a balancing valve core 3-e is slidably connected in the differential pressure pipe 2-e.

When the internal pressure is too large, the balance hole pipe 5-e increases the pressure to the differential pressure pipe 2-e, so that the balance valve core 3-e in the differential pressure pipe 2-e moves reversely, the internal volume is increased, so that the differential pressure is balanced, and vice versa.

Claims

1. A radial magnetic circuit submerged linear motor is characterized in that: the motor water inlet device comprises a primary assembly (1) and a secondary assembly (2) which is matched with the primary assembly (1), wherein sealing systems (3) for preventing water from entering are arranged on two sides of the primary assembly (1), a pressure balancing device (4) is arranged between the secondary assembly (2) and the sealing systems (3), and a lubrication cooling assembly (3-c) for cooling and lubricating a motor is arranged in the secondary assembly (2);

the secondary assembly (2) comprises a base shaft (1-b), wherein base shaft (1-b) connecting assemblies for connecting other external pipes are arranged at two ends of the base shaft (1-b); the base shaft (1-b) is externally provided with magnetic steel (41-b) and a magnetism isolating ring (42-b): the magnetic steel (41-b) and the magnetism isolating ring (42-b) are externally provided with a magnetic steel jacket (43-b), a plurality of magnetic steels (41-b) are arranged, and magnetic poles of the magnetic steels (41-b) arranged on the base shaft (1-b) are N, S series to form a radial magnetic field; the plurality of magnetism isolating rings (42-b) are arranged, and each magnetism isolating ring (42-b) is arranged between every two magnetic steels (41-b);

the base shaft (1-b) connecting assembly comprises secondary connectors (21-b) arranged at two ends of the base shaft (1-b), wherein the two secondary connectors (21-b) are respectively connected with a base shaft (1-b) connecting rod and an upper connecting rod connector (23-b), and the upper connecting rod connector (23-b) is in threaded connection with an upper connecting rod (24-b);

the lubrication cooling component (3-c) is arranged in the base shaft (1-b); the lubrication cooling assembly (3-c) comprises a lubrication oil pipe (31-c); the lubricating oil pipe (31-c) forms an internal circulation oil flow of circulating flow; the lubrication cooling assembly (3-c) comprises an oil pipe sealing ring (32-c): the oil pipe sealing ring (32-c) is arranged between the secondary joint (21-b) and the lubricating oil pipe (31-c), and the lubricating oil pipe (31-c) forms oil circulation.

2. A radial magnetic circuit submersible linear motor according to claim 1, characterized in that: the primary assembly (1) comprises a plurality of sections of iron cores (4-a), a plurality of installation cavities (9-a) are formed in the inner sides of the sections of iron cores (4-a), a coil framework (3-a) is arranged in each installation cavity (9-a), and a group of a plurality of coils (2-a) are wound on each coil framework (3-a).

3. A radial magnetic circuit submersible linear motor according to claim 2, characterized in that: the double-core transformer is characterized in that cross sealing rings (5-a) are arranged on two sides of an inner hole of each iron core (4-a), notch insulating clamps (6-a) are arranged at the leading-out positions of the coils (2-a), lacing wires (8-a) are arranged between every two iron cores (4-a), and the iron cores (4-a) at two ends are respectively an upper connecting iron core (1-a) and a lower connecting iron core (7-a).

4. A radial magnetic circuit submersible linear motor according to claim 1, characterized in that: the sealing system (3) comprises a sealing tube, a flow channel (4-d) is arranged in the middle of the sealing tube, and a multistage sealing mechanism (5-d) is arranged in the flow channel (4-d) of the sealing tube; the multistage sealing mechanism (5-d) comprises a plurality of sealing groups (51-d) and sliding bearings (52-d) arranged on two sides of the sealing groups (51-d), and a plurality of sealing grooves (53-d) for installing sealing rings are formed at the joint of the sliding bearings (52-d) and the sealing pipes.

5. A radial magnetic circuit submersible linear motor according to claim 4, characterized in that: the sliding bearing (52-d) comprises a first bearing (521-d) and a second bearing (522-d), a guide block (10-d) is arranged on one side of the first bearing (521-d) in the sealing tube, and the sealing groove (53-d) is arranged between the guide block (10-d) and the first bearing (521-d), and between the sealing group (51-d) and the first bearing (621-d).

6. A radial magnetic circuit submersible linear motor according to claim 5, characterized in that: a breathing port screen (7-d) is arranged between the guide block (10-d) and the threaded connector (9-d), and the breathing port screen (7-d) is provided with a breathing port (8-d).

7. A radial magnetic circuit submersible linear motor according to claim 1, characterized in that: the pressure balancing device (4) comprises a valve body (1-e), a balancing hole pipe (5-e) is arranged in the middle of the valve body (1-e), a pressure difference pipe (2-e) is communicated with the balancing hole pipe (5-e), a section of the pressure difference pipe (2-e) is provided with a screw (4-e) for sealing installation, and a balancing valve core (3-e) is slidably connected in the pressure difference pipe (2-e).