Oil pumping mechanism for oil-immersed mutual inductor

Abstract

The invention relates to the technical field of electrical equipment detection, and particularly discloses an oil pumping mechanism for an oil-immersed mutual inductor, which comprises a probe machine body, an axial channel and an oil pumping piston are arranged in the probe machine body, the oil pumping piston is driven by a driving assembly to slide back and forth along the axial channel, and a first end cover and a second end cover are respectively fixed at the left end and the right end of the axial channel; the outer side face of the first end cover is provided with a ball ejecting part used for ejecting a sealing ball at the oil inlet end of the oil taking valve in a protruding mode and provided with an oil taking hole communicated with the axial channel. The oil pumping piston is provided with a sensor installation part used for installing an insulating oil detection sensor. The driving assembly is arranged in the axial direction of the axial channel, and the end, away from the oil pumping piston, of the driving assembly extends out of the second end cover. According to the oil pumping mechanism for the oil-immersed mutual inductor, detection can be carried out without taking out insulating oil, and the situation that the normal working environment in equipment is affected due to loss of the insulating oil can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of electrical equipment detection, and in particular to an oil extraction mechanism for an oil-immersed mutual inductor. Background Art

[0002] Oil-immersed electrical equipment mainly includes oil-immersed transformers and oil-immersed mutual inductors, which are very important in power systems because they not only ensure the safety of measuring and protecting equipment, but also improve the reliability and efficiency of the system. By using oil-immersed electrical equipment, the normal operation of electrical equipment can be ensured, and necessary protection can be provided in the event of a failure. For this type of equipment, the internal insulating oil not only plays an insulating role, but also plays a cooling and lubricating role. The detection of insulating oil can timely detect problems such as oil aging, contamination, or internal equipment failures, thereby avoiding equipment failures and accidents and ensuring the safe and stable operation of the power system. By regularly testing the insulating oil, monitoring the changes in oil quality, and replacing or regenerating the oil in a timely manner, the corrosion and wear of the equipment by impurities and acidic substances in the oil can be reduced, thereby extending the service life of the equipment.

[0003] In order to realize the detection of insulating oil (oil temperature, pressure, partial discharge, characteristic gas, etc.), the existing oil-immersed transformers are fixedly provided with an oil extraction joint (or oil extraction valve). The oil inlet end of the oil extraction joint is generally sealed by a sealing ball, and the sealing ball is tightly pressed against the oil inlet end by the internal pressure of the equipment or the elastic force provided by other components; when it is necessary to extract oil, it is necessary to open the sealing cover connected to the outer end of the oil extraction joint, and use the oil extraction tool to push the sealing ball to move, so that the insulating oil inside the equipment flows out through the oil extraction tool; the structure of the existing oil extraction tool can be seen in patents CN110608919B or CN110530673B.

[0004] However, existing oil extraction tools all test the insulating oil after it is removed. This operation is not only cumbersome, but also prone to analytical errors due to sample contamination or gas escape during oil extraction, transportation and laboratory analysis. In addition, the insulating oil has a significant impact on the normal working environment inside the equipment (especially low-oil equipment) before it is refilled after it is removed. Refilling can easily cause impurities and water in the external environment to enter the transformer due to improper operation, which also affects the normal working environment inside the transformer.

[0005] The above technical problems need to be solved urgently. Summary of the invention

[0006] In view of this, an object of the present invention is to provide an oil extraction mechanism for an oil-immersed transformer, which can be used for detection without removing the insulating oil and can avoid affecting the normal working environment inside the equipment due to the loss of insulating oil.

[0007] To achieve the above object, the present invention provides an oil extraction mechanism for an oil-immersed transformer, comprising a probe body for detachably connecting to an oil extraction valve of the oil-immersed transformer;

[0008] The probe body is provided with an axial channel and an oil extraction piston driven by a driving assembly to slide back and forth along the axial channel, and the left and right ends of the axial channel are respectively fixed with a first end cover and a second end cover; the outer side surface of the first end cover is convexly provided with a top ball portion for abutting against a sealing ball at the oil inlet end of the oil extraction valve, and is provided with an oil extraction hole connected with the axial channel;

[0009] The oil pumping piston is provided with a sensor mounting portion for mounting an insulating oil detection sensor. The drive assembly is arranged along the axial direction of the axial channel and one end thereof away from the oil pumping piston extends out from the second end cover.

[0010] As a further improvement to the above technical solution, the outer wall of the probe body is provided with a first external threaded portion for threading with the oil extraction valve and / or a second external threaded portion for threading with the second end cover.

[0011] As a further improvement of the above technical solution, the drive assembly includes a plurality of sleeves which are axially connected in sequence, so that the drive assembly can be extended and retracted along the axial direction and drive the probe body to slide axially; the sleeve includes a first-stage sleeve away from the pumping piston, a final-stage sleeve connected to the pumping piston, and at least one intermediate sleeve arranged between the first-stage sleeve and the final-stage sleeve.

[0012] As a further improvement to the above technical solution, power is transmitted between each stage of sleeves and between the pumping piston and the final stage sleeve through corresponding threaded pairs.

[0013] As a further improvement of the above technical solution, an oil pumping plug is fixedly connected to the end of the first-stage sleeve, and the oil pumping plug extends from the axial hole of the second end cover and is rotatably connected. A force-applying part is formed at the end of the oil pumping plug, and the force-applying part is rotated to cause the sleeves of each stage to rotate and retract in sequence.

[0014] As a further improvement to the above technical solution, the force applying portion is a hexagonal nut structure.

[0015] As a further improvement to the above technical solution, the sensor mounting portion is arranged on the end surface of the oil pumping piston close to the first end cover, and the end surface and the oil pumping plug are both provided with wire holes for the wires to pass through.

[0016] As a further improvement to the above technical solution, the outer side wall of the oil pumping piston is sleeved with a coaxial sealing ring for sealing and / or a guide ring for guiding.

[0017] As a further improvement of the above technical solution, the outer wall of the probe body is radially opened with a first through hole and / or a second through hole connected to the axial channel near the second end cover. The first through hole is used as an oil outlet and is provided with a sealing bolt, and the second through hole is used as an observation window and is provided with a transparent sealing body.

[0018] As a further improvement to the above technical solution, the first end cover is integrally formed with the probe body.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects:

[0020] The present invention provides an oil extraction mechanism for an oil-immersed mutual inductor. When in use, when the probe body moves inward to a certain position in the oil inlet end of the oil extraction valve, the top ball portion can contact the sealing ball and gradually push the sealing ball to move, thereby connecting the inner cavity of the oil-immersed mutual inductor with the axial channel; at this time, the oil extraction piston is driven to move toward the second end cover, and the insulating oil can enter the axial channel through the oil extraction hole and be retained between the first end cover and the oil extraction piston, and the insulating oil detection sensor on the sensor mounting portion can detect the insulating oil; after the detection is completed, if there is no need to replace the insulating oil, the oil extraction piston can be driven to move toward the first end cover to re-inject the extracted insulating oil into the power equipment; therefore, through the oil extraction mechanism, detection can be carried out without taking out the insulating oil, and the normal working environment inside the equipment can be avoided from being affected by the loss of insulating oil.

[0021] The present invention helps to improve the maintenance efficiency and safety of oil-immersed power equipment, especially oil-immersed transformers, while also reducing maintenance costs because frequent insulating oil replacement and possible environmental impacts are avoided. The present invention is very suitable for promotion and application in the field of oil-immersed electrical equipment detection technology.

[0022] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a first structural schematic diagram of the oil pumping mechanism of the present invention;

[0024] Figure 2 It is a second structural schematic diagram of the oil pumping mechanism of the present invention;

[0025] Figure 3 A three-dimensional diagram showing the connection between the oil pumping piston and the driving assembly of the present invention;

[0026] Figure 4 It is a cross-sectional view of the connection between the oil pumping piston and the driving assembly of the present invention;

[0027] Figure 5This is a diagram of a first use state of the oil pumping mechanism of the present invention;

[0028] Figure 6 This is a diagram of a second use state of the oil pumping mechanism of the present invention. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the exemplary embodiments of the present invention and their description are used to explain the present invention and do not constitute a limitation of the present invention.

[0030] Embodiment 1

[0031] like Figures 1 to 6 As shown: This embodiment provides an oil extraction mechanism for an oil-immersed transformer, including a probe body 2 for detachably connecting to an oil extraction valve 1 of the oil-immersed transformer. The structure and principle of the oil extraction valve 1 are the same as those of the prior art, for example, the probe body 2 and the oil extraction valve 1 can be connected by a threaded connection, which will not be described in detail here.

[0032] The present embodiment provides an oil pumping mechanism for an oil-immersed mutual inductor, the main improvement of which lies in that an axial channel 3 and an oil pumping piston 4 which is driven by a driving assembly to slide back and forth along the axial channel 3 are provided in the probe body 2, and a first end cover 5 and a second end cover 6 are fixed to the left and right ends of the axial channel 3 respectively; the outer side surface of the first end cover 5 is convexly provided with a top ball portion 7 for abutting against a sealing ball 1a at the oil inlet end of the oil extraction valve 1, and is provided with an oil extraction hole 8 which is connected to the axial channel 3; a sensor mounting portion 9 for mounting an insulating oil detection sensor is provided on the oil pumping piston 4, and the driving assembly is arranged along the axial direction of the axial channel 3 and its end away from the oil pumping piston 4 extends from the second end cover 6.

[0033] The outer wall of the oil pumping piston 4 and the inner wall of the axial channel 3 are sealed to prevent oil leakage; the top ball portion 7 can be a pin or a rod structure; the top ball portion 7 can be located at the center of the first end cover 5, and a plurality of (the specific number can be determined as needed) oil extraction holes 8 can be evenly arranged on the end surface of the first end cover 5 along the circumferential direction; "left" and "right" are used as the Figure 1 The orientation shown is the standard; the first end cover 5 can be integrally formed with the probe body 2.

[0034] When the probe body 2 moves inward to a certain position in the oil inlet end of the oil extraction valve 1, the top ball part 7 can contact the sealing ball 1a and gradually push the sealing ball 1a to move, so that the inner cavity of the oil-immersed transformer is connected with the axial channel 3; at this time, the oil extraction piston 4 is driven to move toward the second end cover 6, and the insulating oil can enter the axial channel 3 through the oil extraction hole 8 and be retained between the first end cover 5 and the oil extraction piston 4, and the insulating oil detection sensor on the sensor mounting part 9 can detect the insulating oil; after the detection is completed, if there is no need to replace the insulating oil, the oil extraction piston 4 can be driven to move toward the first end cover 5 to re-inject the extracted insulating oil into the power equipment.

[0035] Specifically, the pumping mechanism can be used in the following process: ensure that the oil-immersed transformer is powered off and in a safe state, and prepare necessary tools and safety equipment (such as gloves, goggles, tool boxes, etc.); install an insulating oil detection sensor on the sensor mounting portion 9 of the pumping piston 4 to monitor the state of the insulating oil in real time during the pumping process; activate the drive assembly so that the pumping piston 4 is located at the leftmost end of the axial channel 3; remove the sealing cover of the oil extraction valve 1, and screw one end of the probe body 2 into the oil inlet end of the oil extraction valve 1 and enter the set position; activate the drive assembly so that the pumping piston 4 moves toward the second end cover 6 to perform the oil pumping operation; stop pumping after extracting a proper amount of insulating oil, and monitor its quality and parameters online through the insulating oil detection sensor; external instruments analyze the data collected by the sensor to evaluate the state of the insulating oil and the health of the power equipment; decide whether the insulating oil needs to be processed or replaced based on the results of the oil quality analysis; if necessary, replace or regenerate the oil; otherwise activate the drive assembly so that the pumping piston 4 moves toward the first end cover 5 to perform the oil filling operation.

[0036] In this embodiment, the outer wall of the probe body 2 is provided with a first external threaded portion 10 for threading with the oil extraction valve 1 and a second external threaded portion 11 for threading with the second end cap 6. The first external threaded portion 10 is provided on the left side of the probe body 2, and the second threaded portion 11 is provided on the right side of the probe body 2; through the threaded connection, a stable and detachable connection method can be provided, so that the probe body 2 can be firmly connected to the oil extraction valve 1 and the second end cap 6. This connection method helps to maintain the stability of the structure during the extraction of insulating oil and reduce the risks caused by unstable connection; the design of the threaded connection makes the installation and disassembly of the probe body 2 easier, which is helpful for rapid installation and maintenance on site; of course, the threaded connection can be used in conjunction with sealing elements (such as sealing rings, gaskets, etc.) to effectively improve the sealing performance of the connection parts and prevent leakage of insulating oil.

[0037] In this embodiment, the drive assembly includes a plurality of sleeves that are sequentially connected along the axial direction, so that the drive assembly can be extended and retracted along the axial direction and drive the probe body 2 to slide along the axial direction; the sleeve includes a first-stage sleeve 12 away from the pumping piston 4, a final-stage sleeve 13 connected to the pumping piston 4, and at least one intermediate sleeve arranged between the first-stage sleeve 12 and the final-stage sleeve 13. The multiple-stage sleeves are sequentially connected, which can improve the compactness of the structure and reduce the volume of the mechanism while increasing the effective stroke of the pumping piston 4; the compact arrangement of the sleeves can reduce the overall size of the drive assembly, which is particularly beneficial for application scenarios with limited space; the first-stage sleeve 12 is located at one end of the drive assembly, and the final-stage sleeve 13 directly connected to the pumping piston 4 is located at the other end. Such a design can effectively transmit the driving force and ensure that the reciprocating motion of the pumping piston 4 is stable and reliable; the provision of the intermediate sleeve allows for a modular design of the drive assembly, and the number of sleeves can be increased or decreased as needed to adapt to different design and functional requirements. This modularization also facilitates maintenance and replacement of components. Figure 4 As shown, the driving components can be roughly divided into a first-stage group e, a middle group f and a final group g.

[0038] In this embodiment, power is transmitted between sleeves of each stage and between the pumping piston 4 and the final sleeve 13 through corresponding threaded pairs. By transmitting power through threaded pairs, power transmission can be achieved in a smaller space, making the entire drive assembly more compact, which is especially important for oil-immersed transformers with limited space; threaded connections can provide reliable power transmission during the transmission process due to their good self-locking characteristics, reducing the risks caused by unstable connections; threaded pairs can also effectively transmit torque and reduce the difficulty of operation. The threaded pairs are formed by the corresponding inner and outer threads on the inner walls of the corresponding sleeves and the pumping piston 4.

[0039] In this embodiment, the end of the first-stage sleeve 12 is fixedly connected to an oil pumping plug 14, which extends from the axial hole of the second end cover 6 (located at the center of the second end cover 6) and is connected in a rotatable manner. The end of the oil pumping plug 14 forms a force-applying portion 14a, and the sleeves of each stage are rotated and extended in sequence by rotating the force-applying portion 14a. A rotating bearing can be provided between the oil pumping plug 14 and the axial hole of the second end cover 6 to achieve stable support, and a sealing structure can also be provided. Preferably, the force-applying portion 14a can be a hexagonal nut structure, which can be matched with an existing hexagonal wrench to achieve manual operation of the drive assembly.

[0040] As one example, when the intermediate sleeve is set to level three, the drive assembly may work in the following manner:

[0041] Pumping process: the first-stage sleeve 12 rotates counterclockwise, driving the second-stage sleeve 15 to rotate toward the first-stage sleeve 12. When the external thread of the first-stage sleeve 12 rotates to the left end of the internal thread of the second-stage sleeve 15, the first-stage sleeve 12 and the second-stage sleeve 15 can be regarded as a whole; the first-stage sleeve 12 continues to rotate counterclockwise, driving the third-stage sleeve 16 (and the fourth and final-stage sleeves 13, and the pumping piston 4) to continue to rotate toward the first-stage sleeve 12. When the external thread of the second-stage sleeve 15 rotates to the leftmost end of the internal thread of the third-stage sleeve 16, the first, second and third-stage sleeves 16 can be regarded as a whole; the first-stage sleeve 12 continues to rotate counterclockwise, driving the fourth-stage sleeve 17 (and the final-stage sleeve 13, and the pumping piston 4) to continue to rotate toward the first-stage sleeve 12. The first-stage sleeve 12 continues to rotate counterclockwise, which will drive the final-stage sleeve 13 (and the pumping piston 4) to continue to rotate toward the first-stage sleeve 12, and when the external thread of the fourth-stage sleeve 17 rotates to the leftmost end of the internal thread of the final-stage sleeve 13, the first, second, third, fourth and final-stage sleeves 13 can be regarded as a whole; the first-stage sleeve 12 continues to rotate counterclockwise, which will drive the pumping piston 4 to continue to rotate toward the first-stage sleeve 12, and when the external thread of the final-stage sleeve 13 rotates to the leftmost end of the internal thread of the pumping piston 4, the pumping piston 4 reaches the rightmost end of the working stroke, and the pumping work is completed.

[0042] Oil filling process: at this time, the first, second, third, fourth and final sleeves 13 can be regarded as a whole. When the first sleeve 12 rotates clockwise, the external thread of the final sleeve 13 rotates in the internal thread of the oil pumping piston 4, driving the oil pumping piston 4 to rotate and move toward the top ball 7. When the external thread of the final sleeve 13 rotates to the rightmost end of the internal thread of the oil pumping piston 4, the first, second, third and fourth sleeves 17 are regarded as a whole. The first sleeve 12 continues to rotate clockwise, and the external thread of the fourth sleeve 17 rotates in the internal thread of the final sleeve 13, driving the final sleeve 13 and the oil pumping piston 4 to continue to rotate and move toward the top ball 7. When the external thread of the fourth sleeve 17 rotates to the rightmost end of the internal thread of the final sleeve 13, the first, second and third sleeves 16 are regarded as a whole. The first sleeve 12 continues to rotate clockwise, and the external thread of the third sleeve 16 rotates in the internal thread of the fourth sleeve 17, driving the fourth and final sleeves 17 to rotate and move. The sleeve 13 and the pumping piston 4 continue to rotate and move in the direction of the ejector pin. When the external thread of the tertiary sleeve 16 rotates to the rightmost end of the internal thread of the quaternary sleeve 17, the first and second sleeves 15 are regarded as a whole, and the first sleeve 12 continues to rotate clockwise, and the external thread of the second sleeve 15 rotates in the internal thread of the tertiary sleeve 16, driving the third, fourth and final sleeves 13 and the pumping piston 4 to continue to rotate and move in the direction of the ejector pin. When the external thread of the secondary sleeve 15 rotates to the rightmost end of the internal thread of the tertiary sleeve 16, the first sleeve 12 continues to rotate clockwise, and the external thread of the first sleeve 12 rotates in the internal thread of the second sleeve 15, driving the second, third, fourth and final sleeves 13 and the pumping piston 4 to continue to rotate and move in the direction of the ejector pin. When the external thread of the first sleeve 12 rotates to the rightmost end of the internal thread of the second sleeve 15, the pumping piston 4 reaches the leftmost end of the working stroke, completing the oil injection operation.

[0043] In this embodiment, the sensor mounting portion 9 is arranged on the end surface of the oil extraction piston 4 close to the first end cover 5, and the end surface and the oil extraction plug 14 are both provided with a wire hole 18 for the wire to pass through. The sensor is installed close to the oil extraction hole 8, which can respond to the changes of the insulating oil more quickly and provide timely feedback; the sensor directly contacts the oil, which can monitor the oil quality more accurately; one end of the wire is connected to the sensor, which extends out of the mechanism through the wire hole 18 and the inner cavity of the sleeve, and the other end is connected to the external processing and analysis instrument.

[0044] In this embodiment, the outer wall of the pumping piston 4 is provided with a coaxial sealing ring 19 for sealing and a guide ring 20 for guiding. The main function of the sealing ring 19 is to prevent the leakage of insulating oil during the pumping process and maintain the stability of the internal environment of the oil-immersed transformer; the sealing ring 19 can be a Glay ring structure, for example; the guide ring 20 provides a smooth contact surface to ensure that the pumping piston 4 reciprocates smoothly and linearly in the axial channel 3; the guide ring 20 can be made of polymer material to avoid metal contact between moving parts in the pumping mechanism.

[0045] In this embodiment, the outer wall of the probe body 2 is radially provided with a first through hole 21 and a second through hole 22 connected to the axial channel 3 at a position close to the second end cover 6. The first through hole 21 is used as an oil outlet and is provided with a sealing bolt 23, and the second through hole 22 is used as an observation window and is provided with a transparent sealing body. Under normal use, the first through hole 21 is normally closed, and the sealing bolt is opened only when the insulating oil needs to be extracted for special experiments; the transparent sealing body is fixedly filled in the second through hole 22, and the observation window allows the operator to directly observe the flow and properties of the oil, and conveniently check the internal contamination.

[0046] Embodiment 2

[0047] The present embodiment provides an oil-immersed electrical equipment, which includes an oil extraction valve 1, the oil inlet end of the oil extraction valve 1 is sealed by a sealing ball 1a; the oil inlet end of the oil extraction valve 1 is detachably connected to the oil pumping mechanism described in Example 1; since it applies the aforementioned oil pumping mechanism, it naturally also has the aforementioned beneficial technical effects, which will not be repeated here.

[0048] The oil-immersed power equipment mainly includes oil-immersed transformers and oil-immersed mutual inductors, both of which can be matched with the oil pumping mechanism described in the embodiment to achieve the aforementioned technical effects.

[0049] Finally, it should be noted that this article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only to help understand the core idea of ​​the present invention. Without departing from the principles of the present invention, the present invention may also be improved and modified, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. An oil extraction mechanism for an oil-immersed transformer, comprising a probe body for being detachably connected to an oil extraction valve of the oil-immersed transformer; characterized in that: The probe body is provided with an axial channel and an oil extraction piston driven by a driving assembly to slide back and forth along the axial channel, and the left and right ends of the axial channel are respectively fixed with a first end cover and a second end cover; the outer side surface of the first end cover is convexly provided with a top ball portion for abutting against a sealing ball at the oil inlet end of the oil extraction valve, and is provided with an oil extraction hole connected with the axial channel; The oil pumping piston is provided with a sensor mounting portion for mounting an insulating oil detection sensor. The drive assembly is arranged along the axial direction of the axial channel and one end thereof away from the oil pumping piston extends out from the second end cover.

2. The oil pumping mechanism for an oil-immersed mutual inductor according to claim 1, characterized in that: The outer wall of the probe body is provided with a first external threaded portion for threading with the oil extraction valve and / or a second external threaded portion for threading with the second end cover.

3. The oil pumping mechanism for an oil-immersed mutual inductor according to claim 1, characterized in that: The drive assembly includes a plurality of sleeves which are sequentially connected along the axial direction, so that the drive assembly can be extended and retracted along the axial direction and drive the probe body to slide along the axial direction; the sleeve includes a first-stage sleeve away from the pumping piston, a final-stage sleeve connected to the pumping piston, and at least one intermediate sleeve arranged between the first-stage sleeve and the final-stage sleeve.

4. The oil pumping mechanism for an oil-immersed mutual inductor according to claim 3, characterized in that: Power is transmitted between sleeves at each stage and between the pumping piston and the final sleeve through corresponding thread pairs.

5. The oil pumping mechanism for an oil-immersed mutual inductor according to claim 4, characterized in that: An oil pumping plug is fixedly connected to the end of the first-stage sleeve, and the oil pumping plug extends from the axial hole of the second end cover and is rotatably connected. A force-applying part is formed at the end of the oil pumping plug, and the sleeves of each stage are caused to rotate and extend in sequence by rotating the force-applying part.

6. The oil pumping mechanism for an oil-immersed mutual inductor according to claim 5, characterized in that: The force applying portion is in a hexagonal nut structure.

7. The oil pumping mechanism for an oil-immersed mutual inductor according to claim 5, characterized in that: The sensor mounting portion is arranged on the end surface of the oil pumping piston close to the first end cover, and the end surface and the oil pumping plug are both provided with wire holes for the wires to pass through.

8. An oil pumping mechanism for an oil-immersed transformer according to any one of claims 1 to 7, characterized in that: The outer side wall of the oil pumping piston is sleeved with a coaxial sealing ring for sealing and / or a guide ring for guiding.

9. An oil pumping mechanism for an oil-immersed transformer according to any one of claims 1 to 7, characterized in that: The outer wall of the probe body is radially provided with a first through hole and / or a second through hole connected to the axial channel near the second end cover. The first through hole is used as an oil outlet and is provided with a sealing bolt, and the second through hole is used as an observation window and is provided with a transparent sealing body.

10. An oil pumping mechanism for an oil-immersed mutual inductor according to any one of claims 1 to 7, characterized in that: The first end cover is integrally formed with the probe body.

Images