An oil production device driven by an underground axial flux variable frequency speed regulating motor

Abstract

The invention belongs to the technical field of downhole working tools in the petroleum and natural gas industry, and discloses an downhole oil production device driven by an axial flux variable frequency speed regulating motor, comprising an outer tube, an upper coupling hoop is sleeved on the top of the outer tube, a pump barrel is sleeved on the inner wall of the outer tube, a plunger is sleeved on the inner wall of the pump barrel, a guide ring is sleeved on the lower end of the plunger, three sealing rings with the same structure and in a linear array are arranged at the gap between the upper coupling hoop and the pump barrel, four sand-proof packings with the same structure and symmetrically distributed in pairs are arranged at the gap between the pump barrel and the plunger, a lower coupling hoop is sleeved on the bottom of the outer tube, a spherical shell is fixedly connected in the middle of the central axis of the outer tube, and oil production is achieved by adopting an axial flux motor to drive the plunger to move up and down, and the output power and speed are more flexible and controllable under different working conditions, and the motor operation parameters can be flexibly controlled to improve the oil production efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of downhole working tools in the petroleum and natural gas industry, and in particular to an downhole oil production device driven by an axial magnetic flux variable frequency speed regulating motor. Background Art

[0002] There are two main oil production methods: self-flowing oil production and artificial lifting. In the process of oil well development, after the oil well is tested, the appropriate production method will be selected according to the physical properties and pressure of the oil layer of the oil well. Rod pump oil production is the most widely used oil production method at home and abroad. It has simple equipment, low investment, convenient management and strong adaptability. Rod pump oil production is divided into conventional rod pump oil production and ground driven screw pump oil production. The conventional rod pump oil production device consists of a ground pumping unit, a downhole sucker rod and a pump and other accessories. Its working process is to use a tubing to lower the deep well pump barrel below the liquid level in the well, and a suction valve (fixed valve) is installed at the bottom of the pump barrel. The plunger is lowered into the pump barrel with a sucker rod column, and a discharge valve (floating valve) is installed on the plunger. The up and down reciprocating linear motion generated by the donkey head suspension point of the pumping unit is transmitted to the pumping pump through the sucker rod column to pump oil upward. Rodless pump oil production mainly includes submersible electric centrifugal pump oil production and hydraulic piston pump oil production.

[0003] For example, the invention patent application with publication number CN201310571887.5 discloses a rodless oil production system driven by a downhole permanent magnet linear motor, which consists of three parts: a front piston tube, a magnetic steel, and a tail pipe; the front piston tube is at the top of the system, and plays a role in balancing the pressure difference and preventing sand; the magnetic steel is in the middle of the system, and generates magnetic excitation through power supply by cables, so that the mover performs linear reciprocating motion; the tail pipe at the lower end of the system plays a role in limiting the mover and preventing sand from the motor; the pull-down pump barrel is threadedly connected to the front piston tube, the pull-down pump plunger is connected to the motor pull rod through a conversion joint with a pin, the pull-down pump upper coupling is connected to the oil pipe, the electronic mover drives the pull-down pump plunger to pump oil, and the crude oil enters the oil pipe from the pump barrel.

[0004] The existing technology has the following problems: the rotor and stator design of the permanent magnet linear motor needs to match the linear motion system, the adaptability is low in the oil well environment with high temperature, high pressure and high sand content, the flexibility of the motor output power and speed under different working conditions is limited, and the control system is complex and inconvenient to operate when precise control of the motor operating parameters is required.

[0005] For this purpose, an underground oil production device driven by an axial flux variable frequency speed regulating motor is proposed. Summary of the invention

[0006] In order to solve the problems that permanent magnet linear motors have low adaptability in oil well environments with high temperature, high pressure and high sand content, the flexibility of motor output power and speed under different working conditions is limited, and the control system is complex and inconvenient to operate when precise control of motor operating parameters is required, the present invention provides an downhole oil production device driven by an axial flux variable frequency speed regulation motor.

[0007] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions:

[0008] An underground oil production device driven by an axial magnetic flux variable frequency speed regulating motor comprises an outer tube, an upper coupling is sleeved on the top of the outer tube, a pump barrel is sleeved on the inner wall of the outer tube, a plunger is sleeved on the inner wall of the pump barrel, a guide ring is sleeved on the lower end of the plunger, three sealing rings with the same structure and arranged in a linear array are provided in the gap between the upper coupling and the pump barrel, four sand-proof packings with the same structure and symmetrically distributed in pairs are provided in the gap between the pump barrel and the plunger, a lower coupling is sleeved on the bottom of the outer tube, and a spherical shell is fixedly connected in the middle of the central axis of the outer tube.

[0009] As a further solution of the present invention, four square grooves with the same structure and distributed in a ring array are opened at the upper end of the plunger, a sand retaining ring is fixedly arranged on the top of the plunger, and a top plug is fixedly connected to the central axis of the sand retaining ring. The inner wall of the plunger is provided with an upper oil outlet valve and a lower oil outlet valve, and the upper oil outlet valve and the lower oil outlet valve have the same structure.

[0010] As a further scheme of the present invention, the upper oil outlet valve includes a valve body, a valve core is sleeved on the top of the valve body, a connecting piece is fixedly connected to the bottom of the valve core, a limit column is fixedly connected to the top of the valve core, an elastic device is sleeved on the limit column, four baffles with the same structure and distributed in an annular array are provided on the top of the elastic device, a top frame is fixedly connected to the top of the four baffles, eight through holes with the same structure and distributed in an annular array are opened on the top frame along the central axis, the side wall of the top frame is fixedly connected to the inner wall of the plunger, a valve seat is provided at the bottom of the valve body, the side wall of the valve seat is fixedly connected to the inner wall of the plunger, and a radial flow hole is opened at the central axis of the valve seat.

[0011] As a further solution of the present invention, an oil inlet valve is provided at the lower end of the inner wall of the pump barrel, and the oil inlet valve has the same structure as the lower oil outlet valve.

[0012] As a further solution of the present invention, two first transmission arms with the same structure and symmetrically distributed are fixedly connected to the bottom of the plunger, and rotating arms are respectively provided on the separated sides of the two first transmission arms. Round shafts are respectively rotatably connected at the joints between the two first transmission arms and the two rotating arms, and an axial flux motor is rotatably connected at the gap between the two rotating arms.

[0013] As a further solution of the present invention, the axial flux motor includes a rotating shaft, both ends of the rotating shaft are fixedly connected to the inner wall of the spherical shell and are respectively sleeved with bearings, the rotating shaft is sleeved with a movement, the movement is located in the gap between the two rotating arms, the outer wall of the movement is sleeved with an inner ring, the outer wall of the inner ring is sleeved with an outer ring, rolling bodies are provided at the adjacent parts of the inner ring and the outer ring, the outer wall of the outer ring is sleeved with a stator, the outer wall of the stator is sleeved with a shell, rotors are respectively provided at both ends of the shell, and end covers are respectively fixedly connected to the two rotors on the side away from the shell.

[0014] As a further solution of the present invention, a wire sleeve is fixedly connected to the top of the axial flux motor, a cable is sleeved inside the wire sleeve, a frequency converter is fixedly connected to the top of the cable, and the frequency converter is located on the top of the upper coupling.

[0015] As a further solution of the present invention, a third sleeve is fixedly connected to the bottom of the pump barrel, three sand filter discs with the same structure and distributed in a linear array are fixedly connected inside the third sleeve, a second sleeve is fixedly connected to the bottom of the third sleeve, a first sleeve is fixedly connected to the bottom of the second sleeve, and four retaining springs with the same structure and distributed in a linear array are fixedly connected to the gap between the lower coupling and the third sleeve and the second sleeve.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. The present invention arranges an axial flux motor to drive the plunger to move up and down to realize oil production. The magnetic field of the axial flux motor is realized by controlling the current, and the intensity and direction can be flexibly adjusted. The output power and speed are more flexible and controllable under different working conditions, and flexible control of the motor operating parameters can be realized.

[0018] 2. The present invention is provided with an upper oil outlet valve, a lower oil outlet valve and an oil inlet valve. The oil compresses the valve body of the oil inlet valve due to the pressure difference, the elastic device contracts, and the oil enters the pump barrel. Since the axial magnetic flux motor drives the plunger to move up and down, the pressure in the pump barrel changes, and the oil enters the plunger and is sent to the ground to complete the oil production process. Through the setting of multiple valves, the flexibility and adjustability of the system are increased, the flow rate of oil production is controlled, and at the same time, the occurrence of adverse phenomena such as liquid backflow or hydraulic shock is avoided, thereby ensuring the stable operation of the system.

[0019] 3. The present invention is provided with a sand retaining ring and a sand filter disc to filter sand particles before and after oil intake, thereby protecting the internal motor, improving the quality of produced oil, and improving the production efficiency of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a cross-sectional view of the plunger structure of the present invention;

[0021] Figure 2 is a cross-sectional view of the axial flux motor structure of the present invention;

[0022] Figure 3 It is a cross-sectional view of the oil inlet valve structure of the present invention;

[0023] Figure 4 is an exploded view of the axial flux motor structure of the present invention;

[0024] Figure 5 It is an exploded view of the valve body structure of the present invention.

[0025] Reference numerals: 1, upper coupling; 2, lower coupling; 3, outer tube; 4, pump barrel; 5, plunger; 6, sand-proof packing; 7, sealing ring; 8, sand-proof ring; 9, square groove; 10, top plug; 11, top frame; 12, baffle; 13, elastic device; 14, upper oil outlet valve; 15, lower oil outlet valve; 16, first transmission arm; 17, round shaft; 18, rotating arm; 19, axial flux motor; 1901, end cover; 1902, rotor; 1903, rotating shaft; 1904, stator; 1905 , movement; 1906, inner ring; 1907, rolling element; 1908, outer ring; 1909, housing; 20, bearing; 21, through hole; 22, valve seat; 23, limit column; 24, valve core; 25, connecting piece; 26, retaining ring; 27, first sleeve; 28, second sleeve; 29, third sleeve; 30, sand filter disc; 31, radial flow hole; 32, guide ring; 33, spherical shell; 34, oil inlet valve; 35, frequency converter; 36, wire sleeve; 37, cable; 38, valve body. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] The following will be combined Figure 1-Figure 5 A downhole oil production device driven by an axial flux variable frequency speed regulating motor according to an embodiment of the present invention is described in detail.

[0028] Embodiment 1: Embodiment 1 of the present application discloses an oil production device driven by an axial magnetic flux variable frequency speed regulating motor in a downhole. Figure 1-Figure 3, including an outer tube 3, an upper coupling 1 is sleeved on the top of the outer tube 3, a pump barrel 4 is sleeved on the inner wall of the outer tube 3, a plunger 5 is sleeved on the inner wall of the pump barrel 4, a guide ring 32 is sleeved on the lower end of the plunger 5, three sealing rings 7 with the same structure and in a linear array are provided in the gap between the upper coupling 1 and the pump barrel 4, four sand-proof packings 6 with the same structure and symmetrically distributed in pairs are provided in the gap between the pump barrel 4 and the plunger 5, a lower coupling 2 is sleeved on the bottom of the outer tube 3, and a spherical shell 33 is fixedly connected in the middle of the central axis of the outer tube 3.

[0029] refer to Figure 2 and Figure 4 The bottom of the plunger 5 is fixedly connected with two first transmission arms 16 with the same structure and symmetrically distributed. The two first transmission arms 16 are provided with rotating arms 18 on the separated sides. The two first transmission arms 16 are connected with the two rotating arms 18 at the joints thereof. The axial flux motor 19 is rotatably connected at the gap between the two rotating arms 18. The axial flux motor 19 includes a rotating shaft 1903. The two ends of the rotating shaft 1903 are fixedly connected with the inner wall of the spherical shell 33 and are sleeved with bearings 20 respectively. The rotating shaft 1903 is sleeved with the movement 1 905, the movement 1905 is located in the gap between the two rotating arms 18, the outer wall of the movement 1905 is sleeved with the inner ring 1906, the outer wall of the inner ring 1906 is sleeved with the outer ring 1908, rolling bodies 1907 are provided adjacent to the inner ring 1906 and the outer ring 1908, the outer wall of the outer ring 1908 is sleeved with the stator 1904, the outer wall of the stator 1904 is sleeved with the shell 1909, rotors 1902 are respectively provided at both ends of the shell 1909, and end covers 1901 are respectively fixedly connected to the two rotors 1902 on the side away from the shell 1909.

[0030] refer to Figure 1 A wire sleeve 36 is fixedly connected to the top of the axial flux motor 19, a cable 37 is sleeved inside the wire sleeve 36, a frequency converter 35 is fixedly connected to the top of the cable 37, and the frequency converter 35 is located at the top of the upper coupling 1. A wire sleeve 36 is fixedly connected to the top of the axial flux motor 19, a cable 37 is sleeved inside the wire sleeve 36, and a frequency converter 35 is fixedly connected to the top of the cable 37, and the frequency converter 35 is located at the top of the upper coupling 1.

[0031] Specifically, under the action of the magnetic field, the rotor 1902 rotates to drive the rotating shaft 1903, and the rotating shaft 1903 drives the two rotating arms 18 to make circular motion. The first transmission arm 16 moves back and forth up and down under the drive of the rotating arm 18 and the space limitation of the pump barrel 4, driving the plunger 5 to move up and down. The guide ring 32 reduces the wear of the plunger 5 and the pump barrel 4 due to the up and down movement of the piston 5, and the spherical shell 33 provides sufficient space for the rotation of the rotating arm 18.

[0032] Example 2: Reference Figure 1-Figure 3Four square grooves 9 with the same structure and distributed in a ring array are opened at the upper end of the plunger 5, a sand retaining ring 8 is fixedly set on the top of the plunger 5, and a top plug 10 is fixedly connected and set at the central axis of the sand retaining ring 8. The inner wall of the plunger 5 is provided with an upper oil outlet valve 14 and a lower oil outlet valve 15, and the upper oil outlet valve 14 and the lower oil outlet valve 15 have the same structure.

[0033] Specifically, after the oil enters the plunger 5, pressure is generated as the plunger 5 moves up and down, compressing the elastic device 13, entering the upper part of the plunger 5 through the through hole 21, and then passing through the square groove 9 and being sent to the ground as the top plug 10 opens.

[0034] refer to Figure 1-Figure 3 and Figure 5 The upper oil outlet valve 14 includes a valve body 38, a valve core 24 is sleeved on the top of the valve body 38, a connecting piece 25 is fixedly connected to the bottom of the valve core 24, a limiting column 23 is fixedly connected to the top of the valve core 24, an elastic device 13 is sleeved on the limiting column 23, four baffles 12 with the same structure and distributed in an annular array are provided on the top of the elastic device 13, and a top frame 11 is fixedly connected to the top of the four baffles 12. The top of the top frame 11 has eight through holes 21 with the same structure and distributed in an annular array along the central axis, and the side wall of the top frame 11 is fixedly connected to the inner wall of the plunger 5. A valve seat 22 is provided at the bottom of the valve body 38, and the side wall of the valve seat 22 is fixedly connected to the inner wall of the plunger 5. A radial flow hole 31 is provided at the central axis of the valve seat 22, and an oil inlet valve 34 is provided at the lower end of the inner wall of the pump barrel 4. The oil inlet valve 34 has the same structure as the lower oil outlet valve 15.

[0035] Specifically, under the action of pressure, the oil compresses the valve body 38 of the oil inlet valve 34, the elastic device 13 contracts, the limit column 23 controls the compression limit, the oil enters the pump barrel 4, and continues to rise through the through hole 21. Since the axial flux motor 19 drives the plunger 5 to move up and down, the gas in the pump barrel 4 is compressed, and the oil enters the plunger 5 and is sent to the ground, completing the oil production process.

[0036] Example 3: Reference Figure 1-Figure 3 A third sleeve 29 is fixedly connected to the bottom of the pump barrel 4, three sand filter discs 30 with the same structure and distributed in a linear array are fixedly connected inside the third sleeve 29, a second sleeve 28 is fixedly connected to the bottom of the third sleeve 29, a first sleeve 27 is fixedly connected to the bottom of the second sleeve 28, and four retaining springs 26 with the same structure and distributed in a linear array are fixedly connected at the gap between the lower coupling 2 and the third sleeve 29 and the second sleeve 28.

[0037] Specifically, the oil enters the first sleeve 27 and the second sleeve 28, and the large sand particles are filtered under the action of the sand filter disc 30, and the retaining spring 26 prevents the sleeves from moving axially.

[0038] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. An underground oil production device driven by an axial magnetic flux variable frequency speed regulating motor, comprising an outer tube (3), characterized in that: The top of the outer tube (3) is sleeved with an upper coupling (1), the inner wall of the outer tube (3) is sleeved with a pump barrel (4), the inner wall of the pump barrel (4) is sleeved with a plunger (5), the lower end of the plunger (5) is sleeved with a guide ring (32), three sealing rings (7) of the same structure and arranged in a linear array are provided in the gap between the upper coupling (1) and the pump barrel (4), four sand-proof packings (6) of the same structure and arranged symmetrically in pairs are provided in the gap between the pump barrel (4) and the plunger (5), the bottom of the outer tube (3) is sleeved with a lower coupling (2), a spherical shell (33) is fixedly connected in the middle of the central axis of the outer tube (3), and four sealing rings (7) of the same structure and arranged in a circular array are provided at the upper end of the plunger (5). A square groove (9) is arranged on the top of the plunger (5), a sand retaining ring (8) is fixedly arranged on the top of the plunger (5), a top plug (10) is fixedly connected to the central axis of the sand retaining ring (8), an upper oil outlet valve (14) and a lower oil outlet valve (15) are arranged on the inner wall of the plunger (5), the upper oil outlet valve (14) and the lower oil outlet valve (15) have the same structure, the upper oil outlet valve (14) comprises a valve body (38), a valve core (24) is sleeved on the top of the valve body (38), a connecting piece (25) is fixedly connected to the bottom of the valve core (24), a limiting column (23) is fixedly connected to the top of the valve core (24), the limiting column (23) is sleeved on the elastic device (13), and the top of the elastic device (13) is provided with four structurally similar The valve body (38) comprises a valve seat (22) arranged at the bottom of the valve body (38), the side wall of the valve seat (22) being fixedly connected to the inner wall of the plunger (5), a radial flow hole (31) being arranged at the center axis of the valve seat (22), and two first transmission arms (16) being arranged at the bottom of the valve body (38) and being symmetrically distributed with each other. The two first transmission arms (16) are respectively provided with a rotation hole (21) on the separated sides thereof. A movable arm (18), a circular shaft (17) is rotatably connected to the joints of the two first transmission arms (16) and the two rotating arms (18), an axial flux motor (19) is rotatably connected to the gap between the two rotating arms (18), the axial flux motor (19) comprises a rotating shaft (1903), both ends of the rotating shaft (1903) are fixedly connected to the inner wall of the spherical shell (33) and are respectively sleeved with bearings (20), the rotating shaft (1903) is sleeved with a movement (1905), the movement (1905) is located in the gap between the two rotating arms (18), the outer wall of the movement (1905) is sleeved with an inner ring (1906), and the outer wall of the inner ring (1906) is sleeved with an outer ring (1908),A rolling body (1907) is disposed adjacent to the inner ring (1906) and the outer ring (1908), a stator (1904) is sleeved on the outer wall of the outer ring (1908), a housing (1909) is sleeved on the outer wall of the stator (1904), rotors (1902) are disposed at both ends of the housing (1909), and end covers (1901) are fixedly connected to the sides of the two rotors (1902) away from the housing (1909).

2. The oil production device driven by an underground axial magnetic flux variable frequency speed regulating motor according to claim 1, characterized in that: An oil inlet valve (34) is provided at the lower end of the inner wall of the pump barrel (4), and the oil inlet valve (34) has the same structure as the lower oil outlet valve (15).

3. The oil production device driven by an underground axial magnetic flux variable frequency speed regulating motor according to claim 2, characterized in that: A wire sleeve (36) is fixedly connected to the top of the axial flux motor (19), a cable (37) is sleeved inside the wire sleeve (36), and a frequency converter (35) is fixedly connected to the top of the cable (37), and the frequency converter (35) is located on the top of the upper coupling (1).

4. The oil production device driven by an underground axial magnetic flux variable frequency speed regulating motor according to claim 3, characterized in that: A third sleeve (29) is fixedly connected to the bottom of the pump barrel (4), three sand filter discs (30) having the same structure and arranged in a linear array are fixedly connected inside the third sleeve (29), a second sleeve (28) is fixedly connected to the bottom of the third sleeve (29), a first sleeve (27) is fixedly connected to the bottom of the second sleeve (28), and four retaining springs (26) having the same structure and arranged in a linear array are fixedly connected to the gap between the lower coupling (2) and the third sleeve (29) and the second sleeve (28).

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