Electric heating and monitoring oil extraction device suitable for slim hole

Abstract

The invention relates to the technical field of oil production equipment, and provides an electric heating and monitoring oil production device suitable for slim holes, comprising a Christmas tree, an outer pipe arranged at the bottom of the Christmas tree, an inner pipe arranged in the outer pipe, an electric heating assembly arranged in the inner pipe, and a flow monitoring assembly arranged in the outer pipe; dynamic adjustment of the heating power and range of the telescopic heating plate in the oil extraction process is achieved through linkage of the second rotating shaft, the universal joint, the first limiting disc, the second limiting disc and other assemblies, when the flow speed is increased, the sliding block slides under the centrifugal force effect, and the telescopic heating plate is driven to expand the heating range and increase the heating power through transmission mechanisms such as the connecting rod; the crude oil flow change is adapted; when the oil extraction speed is reduced, the spring is reset, the second limiting disc is separated, the telescopic heating plate is recovered to the initial state through the torsional spring, the second limiting rod and other assemblies, the device can adjust the heating state in real time according to the oil extraction speed and the crude oil flow, automatic control is achieved, and the adaptability and flexibility of the device are enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of oil production equipment, in particular to an oil production device suitable for electric heating and monitoring of small wells. Background Art

[0002] With the continuous growth of global energy demand and the increasing depletion of conventional oil reservoir resources, the oil extraction industry is gradually expanding into areas with complex geological conditions such as low permeability reservoirs, heavy oil reservoirs and marginal reservoirs. These reservoirs generally have problems such as high crude oil viscosity, poor fluidity, and strong reservoir heterogeneity, which makes it difficult to achieve efficient development with traditional oil production technology; in particular, how to achieve accurate flow monitoring, efficient crude oil heating, and dynamic oil production control under small wellbore conditions has become a core issue in improving oilfield development efficiency and economic benefits.

[0003] Small hole technology has gradually become popular in the development of low permeability and heavy oil reservoirs due to its advantages such as low drilling cost, environmental friendliness, and adaptability to complex well types. Some technologies attempt to use the ground to indirectly infer flow, but they cannot reflect the dynamic changes downhole in real time. In addition, traditional heavy oil production relies on electric heating technology to reduce crude oil viscosity, but the existing electric heating system mostly uses fixed power or simple temperature control mode, which cannot dynamically adjust the heating intensity according to the real-time flow, especially when the oil production rate changes suddenly, it cannot match the changes in crude oil heat demand caused by flow fluctuations; for example, in the rapid oil production stage, high-flow crude oil needs short-term high-intensity heating to maintain the target temperature, but fixed power is prone to insufficient heating; on the contrary, low flow rates may cause overheating and coking. Summary of the invention

[0004] The present invention provides an electric heating and oil production monitoring device suitable for small boreholes. By driving a second rotating shaft to rotate through a motor, not only can the conjugate rotor achieve accurate flow measurement of the liquid in the well, but also three groups of flow meters can be driven to run synchronously, thereby ensuring the flow in each through slot is consistent, thereby improving the efficiency and accuracy of the oil production operation. Furthermore, by engaging an electric telescopic rod with a rotating rod, the heating power and range of the telescopic heating plate can be adjusted. During conventional oil production, the telescopic heating plate maintains its initial state, thereby saving energy and reducing wear, thereby providing an efficient, energy-saving and reliable solution for oil production, thereby solving the problems raised in the background technology.

[0005] The technical solution of the present invention is as follows: An electric heating and monitoring oil production device suitable for small wells comprises: an oil production tree, an outer tube is arranged at the bottom of the oil production tree, an inner tube is arranged inside the outer tube, an electric heating component is arranged inside the inner tube, and a flow monitoring component is arranged inside the outer tube; The electric heating assembly comprises a telescopic heating plate, which is fixedly connected to the outer tube, and racks are fixedly connected to both ends of the telescopic heating plate. A gear is arranged in the middle of the two racks, and the gear is meshed with the racks. When the gear rotates, the telescopic heating plate is driven to move synchronously through the racks to realize dynamic adjustment of the heating range, and a rotating rod is fixedly connected to the side of the gear away from the telescopic heating plate; The flow monitoring component includes a fixed block, which is fixedly connected between the outer tube and the inner tube. The interior of the fixed block is hollow, providing an installation space for the flow meter and protecting the flow meter from the harsh environment in the wellbore. Four through grooves are evenly distributed on the fixed block, and the flow meter is arranged in the through grooves.

[0006] Furthermore, a circular groove one is provided in the outer tube, an annular groove is provided inside the circular groove one, two ends of the telescopic heating plate are fixedly connected to the inner walls on both sides of the annular groove, and the rotating rod is rotatably connected to the circular groove one.

[0007] Furthermore, one of the racks is fixedly connected to a limit rod 1 on a side away from the gear, and a disk is rotatably connected to one side of the rack in the annular groove, and a limit rod 2 is fixedly connected to the disk. A plurality of limit rods 2 are provided, and a plurality of limit rods 2 are distributed in a semicircular shape on the disk, and the other side of the disk is connected to the inner wall of the annular groove through a torsion spring. When the disk rotates, the torsion spring will be stretched or compressed, thereby storing energy. The stored energy will be released when needed to drive the disk and the limit rod 2 to rotate in the opposite direction, thereby realizing automatic resetting of the telescopic heating plate, thereby improving the automation and stability of the oil production system. A protrusion is fixedly connected to the annular groove between the limit rods 2, and the protrusion is arc-shaped, but no protrusion is provided between the limit rods 2 at the top half.

[0008] Furthermore, the flow meter includes control ends fixedly connected to both sides of the flow meter, the control ends are located on both sides of the flow meter, and are located in the hollow part of the fixed block and between the two through slots 1, and a conjugate rotor is rotatably connected in the through slot 1.

[0009] Furthermore, there are two conjugate rotors in total, which are engaged with each other. When rotating, the two conjugate rotors can continuously divide the measured petroleum into known single volume parts. A rotating shaft 2 is penetrated through the middle of the two conjugate rotors, and one end of the two conjugate rotors extends out of the outer shell of the control end.

[0010] Furthermore, one end of the rotating shaft 2 on one of the conjugate rotors is fixedly connected to a bevel gear 1, a bevel gear 2 is provided on one side of the bevel gear 1, the bevel gear 1 is meshed with the bevel gear 2, and the bevel gear 2 is fixedly connected to the rotating shaft 2 in the other flowmeter.

[0011] Furthermore, one end of the rotating shaft 2 that is not connected to the bevel gear 1 is fixedly connected to a universal joint, and one end of the universal joint away from the rotating shaft 2 is fixedly connected to a limiting plate 1, and four through slots 2 are evenly distributed on the limiting plate 1, and a slider is slidably connected in the through slots 2; The rotating rod is slidably connected with the second limiting plate, the second limiting plate is rotatably connected with the sliding block with a connecting rod, and a spring is fixedly connected between the first limiting plate and the second limiting plate.

[0012] Furthermore, a through slot three with the same size as the rotating rod is opened in the middle of the second limiting plate, a circular slot three is opened on one side of the second through slot on the second limiting plate, a limiting block one is fixedly connected in the second circular slot, and the limiting block one is provided with a plurality of; One end of the rotating rod away from the gear is fixedly connected to the second limiting block, and the second limiting block is provided with a plurality of them. Both the first limiting block and the second limiting block are elliptical.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention heats the liquid in the well through a telescopic heating plate. The liquid passes through the through slot 1 to drive the conjugate rotor to rotate. The liquid is continuously divided into single volume parts by the mutually meshing conjugate rotors. The conjugate rotors rotate to drive the bevel gear 1 and the bevel gear 2 to drive multiple flow meters to run synchronously. This design realizes the continuous metering of the liquid during the oil production process, ensures that the flow rate in each through slot 1 is the same, improves the accuracy and synchronization of the flow measurement, provides accurate flow data support for oil production operations, and enhances work efficiency and operational reliability.

[0014] 2. The present invention realizes the dynamic adjustment of the heating power and range of the telescopic heating plate during oil production through the linkage of the second rotating shaft, the universal joint, the first limit plate and the second limit plate. When the flow rate increases, the slider slides under the action of centrifugal force, and the telescopic heating plate is driven to expand the heating range through the transmission mechanism such as the connecting rod, thereby increasing the heating power to adapt to the change of crude oil flow; When the oil production speed slows down, the spring resets, limit plate 1 and limit plate 2 separate, and the telescopic heating plate is restored to its initial state through components such as torsion spring and limit rod 2. The device can adjust the heating state in real time according to the oil production speed and crude oil flow rate to ensure that the crude oil flows at the optimal temperature, improve oil production efficiency, and realize automatic control at the same time, enhancing the adaptability and flexibility of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a stereogram of the device of the present invention; Figure 2 It is a structural diagram of the device of the present invention; Figure 3 is a cross-sectional view of the device of the present invention; Figure 4 It is a structural diagram of the annular groove of the device of the present invention; Figure 5 It is a disassembled diagram of the flow monitoring component of the device of the present invention; Figure 6 It is a structural diagram of the flow monitoring component of the device of the present invention; Figure 7 is a cross-sectional view of the limiting disk of the device of the present invention; Figure 8 The present invention Figure 1 Enlarged view of point A in the middle; Fig. 9 The present invention Figure 2 Enlarged view of point B in the middle; Fig.10 The present invention Figure 4 Enlarged view of center C.

[0016] In the figure: 1. Christmas tree; 2. Outer tube; 3. Inner tube; 31. Circular groove 1; 32. Annular groove; 4. Electric heating assembly; 41. Telescopic heating plate; 42. Rack; 421. Limit rod 1; 422. Disc; 423. Limit rod 2; 424. Bump; 43. Gear; 44. Rotating rod; 5. Flow monitoring assembly; 51. Fixed block; 52. Through groove 1; 53. Flow meter; 531. Control end; 532. Conjugate rotor; 5321. Rotating shaft 2; 5322. Bevel gear 1; 5323. Bevel gear 2; 54. Universal joint; 55. Limiting plate 1; 551. Spring; 56. Through groove 2; 57. Sliding block; 58. Limiting plate 2; 581. Circular groove 2; 582. Limiting block 1; 583. Limiting block 2; 584. Through groove 3; 59. Connecting rod. DETAILED DESCRIPTION

[0017] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0018] like Figure 1-Figure 10 As shown, the present invention provides an electric heating and monitoring oil production device suitable for small wells, comprising: an oil production tree 1, an outer tube 2 is arranged at the bottom of the oil production tree 1, an inner tube 3 is arranged inside the outer tube 2, an electric heating component 4 is arranged inside the inner tube 3, and a flow monitoring component 5 is arranged inside the outer tube 2; The electric heating assembly 4 includes a telescopic heating plate 41, which is fixedly connected to the outer tube 2. Both ends of the telescopic heating plate 41 are fixedly connected with racks 42, and the heating range and power can be dynamically adjusted according to the crude oil flow and temperature requirements to ensure that the crude oil flows at an optimal temperature, reduce viscosity, and improve oil recovery efficiency. A gear 43 is provided in the middle of the two racks 42, and the gear 43 is meshed with the racks 42. When the gear 43 rotates, the first and last telescopic heating plates 41 are driven to move synchronously through the racks 42 to achieve dynamic adjustment of the heating range. A rotating rod 44 is fixedly connected to the side of the gear 43 away from the telescopic heating plate 41; The flow monitoring assembly 5 includes a fixed block 51, which is fixedly connected between the outer tube 2 and the inner tube 3. The interior of the fixed block 51 is hollow, providing an installation space for the flow meter 53 and protecting the flow meter 53 from the harsh environment in the wellbore. Four through grooves 52 are evenly distributed on the fixed block 51, and a flow meter 53 is arranged in the through groove 52 for real-time monitoring of crude oil flow at different positions. This multi-point monitoring can provide more accurate flow data, which helps to accurately control the heating range and power of the telescopic heating plate 41 and further optimize oil production efficiency.

[0019] As a technical solution of the present invention, a circular groove 31 is opened in the outer tube 2, an annular groove 32 is opened inside the circular groove 31, both ends of the telescopic heating plate 41 are fixedly connected to the inner walls on both sides of the annular groove 32, and the rotating rod 44 is rotatably connected to the circular groove 31.

[0020] As a technical solution of the present invention, one side of the rack 42 away from the gear 43 is fixedly connected to a limiting rod 1 421, and a disc 422 is rotatably connected to one side of the rack 42 in the annular groove 32, and a limiting rod 2 423 is fixedly connected to the disc 422. The limiting rod 2 423 is provided with a plurality of limiting rods 2 423, and the plurality of limiting rods 2 423 are distributed in a semicircular shape on the disc 422. The other side of the disc 422 is connected to the inner wall of the annular groove 32 through a torsion spring. When the disc 4 When 22 rotates, the torsion spring will be stretched or compressed, thereby storing energy. The stored energy is released when needed to drive the disc 422 and the limit rod 423 to rotate in the opposite direction, thereby realizing the automatic resetting of the telescopic heating plate 41, thereby improving the automation and stability of the oil production system. The annular groove 32 is fixedly connected with a protrusion 424 between the limit rods 423, and the protrusion 424 is arc-shaped, but no protrusion 424 is provided between the limit rods 423 at the top half.

[0021] As a technical solution of the present invention, the flow meter 53 includes a control end 531 fixedly connected to both sides of the flow meter 53. The control end 531 is located on both sides of the flow meter 53, and is located in the hollow part of the fixed block 51 and between the two through grooves 52. A conjugate rotor 532 is rotatably connected in the through groove 52.

[0022] As a technical solution of the present invention, there are two conjugate rotors 532, which are engaged with each other. When rotating, the two conjugate rotors 532 can continuously divide the measured petroleum into known single volume parts. A rotating shaft 5321 is penetrated through the middle of the two conjugate rotors 532, and one end of the two conjugate rotors 532 extends out of the outer shell of the control end 531.

[0023] As a technical solution of the present invention, one end of the rotating shaft 5321 on one of the conjugate rotors 532 is fixedly connected to a bevel gear 5322, a bevel gear 5323 is provided on one side of the bevel gear 5322, the bevel gear 1 5322 is meshed with the bevel gear 2 5323, and the bevel gear 2 5323 is fixedly connected to the rotating shaft 5321 in another of the flowmeters 53.

[0024] As a technical solution of the present invention, one end of the second rotating shaft 5321 that is not connected to the first bevel gear 5322 is fixedly connected to a universal joint 54, and one end of the universal joint 54 away from the second rotating shaft 5321 is fixedly connected to a limiting plate 1 55, and four through grooves 2 56 are evenly distributed on the limiting plate 1 55, and a slider 57 is slidably connected in the through grooves 2 56; The rotating rod 44 is slidably connected with a second limiting plate 58 , the second limiting plate 58 is rotatably connected with the slider 57 with a connecting rod 59 , and a spring 551 is fixedly connected between the first limiting plate 55 and the second limiting plate 58 .

[0025] As a technical solution of the present invention, a through slot 3 584 having the same size as the rotating rod 44 is provided in the middle of the second limiting plate 58, and a circular slot 2 581 is provided on one side of the through slot 3 584 on the second limiting plate 58, and a limiting block 1 582 is fixedly connected in the circular slot 2 581, and the limiting block 1 582 is provided with a plurality of; One end of the rotating rod 44 away from the gear 43 is fixedly connected to the limiting block 2 583, and the limiting block 2 583 is provided with a plurality of limiting blocks. The limiting block 1 582 and the limiting block 2 583 are both elliptical. When the ends of the two contact each other, they will slide down along the arc surface of the side to prevent jamming.

[0026] Working principle: like Figure 1-Figure 2 and Figure 5-Figure 10 As shown, when oil production is carried out, the staff starts the telescopic heating plate 41 to heat the liquid in the well, and the liquid passes through the through slot 1 52 and drives the two conjugate rotors 532 to rotate, and the conjugate rotors 532 drive the second shaft 5321 to rotate. Since the two conjugate rotors 532 are engaged with each other, the two conjugate rotors 532 can continuously divide the measured liquid into known single volume parts when rotating, and the end of the second shaft 5321 away from the motor drives the bevel gear 1 5322 to rotate, and the bevel gear 1 5322 is engaged with the bevel gear 2 5323, thereby driving the bevel gear 2 5323 to rotate, and the bevel gear 2 5323 drives the flow meter 53 on one side to operate and measure the liquid flow. According to the above steps, the remaining two groups of flow meters 53 are driven to operate, so that they can operate synchronously, and the flow in each through slot 1 52 is the same.

[0027] like Figure 1-Figure 2 and Figure 3-Figure 10As shown, the rotation of the second shaft 5321 drives the universal joint 54 to rotate, and the universal joint 54 drives the limit plate 1 55 to rotate. Since the limit plate 2 58 is slidably connected with the rotating rod 44 at this time, when the limit plate 1 55 drives the connecting rod 59 to rotate, and then drives the limit plate 2 58 to rotate through the connecting rod 58, the gear 43 will not rotate accordingly; when the flow rate increases, the conjugate rotor 532 drives the second shaft 5321 to rotate faster, the second shaft 5321 drives the universal joint 54 to rotate faster, and the universal joint 54 drives the limit plate 1 55 to rotate. As the speed exceeds the critical threshold, this At this time, the slider 57 on the limit plate 1 55 begins to feel the significant centrifugal force. Driven by the centrifugal force, the slider 57 begins to slide in the direction away from the through groove 2 56 and pulls one end of the connecting rod 59 to rotate. The other end of the connecting rod 59 pulls the limit plate 2 58 to move towards the limit plate 1 55 and compresses the spring 551. At the same time, the plurality of limit blocks 1 582 in the circular groove 2 581 and the plurality of limit blocks 2 583 on the rotating rod 44 are engaged with each other. Since both are elliptical, when the ends of the two contact each other, they will slide down along the arc surface of the side to enter. The rotation of the gear 43 drives the racks 42 on both sides to move in opposite directions, and pulls the telescopic heating plates 41 on both sides away from each other, thereby dynamically adjusting the heating power and heating range of the telescopic heating plates 41 to adapt to the changes in the crude oil flow rate, so that the device can adjust the heating state in real time according to the actual oil production speed and the changes in the crude oil flow rate, ensuring that the crude oil flows at the optimal temperature, thereby improving the oil production efficiency; at the same time, when the rack 42 moves, the limit plate 2 58 drives the rotating rod 44 to rotate, and the rotating rod 44 drives the gear 43 to rotate, and the gear 43 rotates to drive the racks 42 on both sides to move in opposite directions, and pulls the telescopic heating plates 41 on both sides away from each other, thereby dynamically adjusting the heating power and heating range of the telescopic heating plates 41 to adapt to the changes in the crude oil flow rate, so that the device can adjust the heating state in real time according to the actual oil production speed and the changes in the crude oil flow rate, ensuring that the crude oil flows at the optimal temperature, and improving the oil production efficiency. The rod 1 421 pushes the limiting rod 2 423 to drive the disk 422 to rotate, thereby compressing the torsion spring, and the plurality of limiting rods 2 423 pass through the arc-shaped protrusion 424 through the thrust of the limiting rod 1 421, until the protrusion 424 is located between the last limiting rod 2 423 and the second to last limiting rod 2 423. At this time, the limiting rod 1 421 moves the limiting rod 2 423 counterclockwise in the upward process, but cannot pass through the protrusion 424. When the rack 42 is completely away from the limiting rod 2 423 at the bottom, the protrusion 424 restricts the limiting rod 2 423 from rotating clockwise. like Figure 1-Figure 10As shown, when the oil production speed slows down, the centrifugal force is lost, and the spring 551 pushes the limit plate 2 58 to slide away from the limit plate 1 55, and separates the limit block 1 582 and the limit block 2 583, and at the same time pulls the connecting rod 59 to rotate, and the connecting rod 59 pulls the slider 57 to slide in the through groove 2 56, so that the rotating rod 44 is separated from the limit plate 2 58. When the limit plate 2 58 rotates, it cannot drive the rotating rod 44 to rotate. At this time, the limit rod 2 423 at the top half is not restricted by the protrusion 424, and one side of the disk 422 The torsion spring drives the disc 422 to rotate clockwise, and drives the limiting rod 2 423 to rotate synchronously. The limiting rod 2 423 pushes the limiting rod 1 421 to move downward, thereby driving the rack 42 to move downward. As the rack 42 moves downward, the limiting rod 1 421 pushes the outermost limiting rod 2 423 at the bottom to rotate clockwise, and causes the limiting rod 2 423 at the bottom to rotate clockwise, thereby returning to the original position, and driving the telescopic heating plates 41 on both sides to approach each other, returning to the initial state, and preparing for the next rapid oil production operation.

[0028] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A device for electric heating and monitoring oil production in small wells, comprising: A Christmas tree (1), characterized in that an outer tube (2) is arranged at the bottom of the Christmas tree (1), an inner tube (3) is arranged inside the outer tube (2), an electric heating component (4) is arranged inside the inner tube (3), and a flow monitoring component (5) is arranged inside the outer tube (2); The electric heating assembly (4) comprises a telescopic heating plate (41), the telescopic heating plate (41) being fixedly connected inside the outer tube (2), racks (42) being fixedly connected to both ends of the telescopic heating plate (41), a gear (43) being provided in the middle of the two racks (42), the gear (43) being meshed with the racks (42), and a rotating rod (44) being fixedly connected to the side of the gear (43) away from the telescopic heating plate (41); The flow monitoring assembly (5) comprises a fixed block (51), the fixed block (51) being fixedly connected between the outer tube (2) and the inner tube (3), the interior of the fixed block (51) being hollow, the fixed block (51) being evenly distributed with four through slots (52), and a flow meter (53) being arranged in the through slots (52).

2. A device for electric heating and monitoring oil production in a small wellbore as claimed in claim 1, characterized in that: A circular groove (31) is provided in the outer tube (2), an annular groove (32) is provided inside the circular groove (31), two ends of the telescopic heating plate (41) are fixedly connected to the inner walls of both sides of the annular groove (32), and the rotating rod (44) is rotatably connected to the circular groove (31).

3. A device for electric heating and monitoring oil production in small wells as claimed in claim 2, characterized in that: A limiting rod 1 (421) is fixedly connected to one side of the rack (42) away from the gear (43); a disk (422) is rotatably connected to one side of the rack (42) in the annular groove (32); a limiting rod 2 (423) is fixedly connected to the disk (422); a plurality of limiting rods 2 (423) are provided, and the plurality of limiting rods 2 (423) are distributed in a semicircular shape on the disk (422); the other side of the disk (422) is connected to the inner wall of the annular groove (32) via a torsion spring; a protrusion (424) is fixedly connected to the annular groove (32) between the limiting rods 2 (423); the protrusion (424) is arc-shaped, but no protrusion (424) is provided between the limiting rods 2 (423) at the top half.

4. The device for electric heating and monitoring oil production in small wells as claimed in claim 1, characterized in that: The flow meter (53) comprises control ends (531) fixedly connected to both sides of the flow meter (53); the control ends (531) are located on both sides of the flow meter (53) and are located in a hollow portion of the fixed block (51) and between the two through slots 1 (52); a conjugate rotor (532) is rotatably connected in the through slot 1 (52).

5. A device for electric heating and monitoring oil production in small wells as claimed in claim 4, characterized in that: There are two conjugate rotors (532) in total, the two conjugate rotors (532) are engaged with each other, a second rotating shaft (5321) is provided through the middle of the two conjugate rotors (532), and one end of the two conjugate rotors (532) extends out of the outer shell of the control end (531).

6. A device for electric heating and monitoring oil production in small wells as claimed in claim 5, characterized in that: One end of the second rotating shaft (5321) on one of the conjugate rotors (532) is fixedly connected to a bevel gear one (5322), a bevel gear two (5323) is provided on one side of the bevel gear one (5322), the bevel gear one (5322) is meshed with the bevel gear two (5323), and the bevel gear two (5323) is fixedly connected to the second rotating shaft (5321) in the other flow meter (53).

7. A device for electric heating and monitoring oil production in small wells as claimed in claim 6, characterized in that: One end of the second rotating shaft (5321) not connected to the first bevel gear (5322) is fixedly connected to a universal joint (54), and one end of the universal joint (54) away from the second rotating shaft (5321) is fixedly connected to a limiting plate (55), and the limiting plate (55) is evenly distributed with four second through grooves (56), and a slider (57) is slidably connected in the second through grooves (56); The rotating rod (44) is slidably connected to a second limiting plate (58), a connecting rod (59) is rotatably connected between the second limiting plate (58) and the sliding block (57), and a spring (551) is fixedly connected between the first limiting plate (55) and the second limiting plate (58).

8. A device for electric heating and monitoring oil production in small wells as claimed in claim 7, characterized in that: A through slot three (584) having the same size as the rotating rod (44) is provided in the middle of the second limiting plate (58); a circular slot two (581) is provided on one side of the through slot three (584) on the second limiting plate (58); a limiting block one (582) is fixedly connected in the second circular slot (581); and the limiting block one (582) is provided with a plurality of; One end of the rotating rod (44) away from the gear (43) is fixedly connected to the second limiting block (583), and the second limiting block (583) is provided with a plurality of them. Both the first limiting block (582) and the second limiting block (583) are elliptical.

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