Pressure-maintaining sealing detection device for oil-immersed transformer

Abstract

The invention discloses an oil-immersed transformer pressure-maintaining sealing detection device, and relates to the technical field of detection devices, the oil-immersed transformer pressure-maintaining sealing detection device comprises a transformer body, the outer surface of the transformer body is provided with an oil storage tank, and the outer surface of the transformer body is provided with a preliminary survey assembly used for preliminarily detecting whether the inner wall of the oil storage tank is slightly damaged. According to the pressure-maintaining sealing detection device for the oil-immersed transformer, when the infrared measuring instrument detects that a suspicious gap exists in the outer wall of the oil storage tank, the negative pressure bin can be inserted into the oil storage tank and rotated in all directions to directly face the suspicious small gap in the inner wall of the oil storage tank, and the negative pressure bin is moved to be tightly attached to the inner wall of the oil storage tank; the oil dirt at the position is cleaned up in a heating and negative pressure mode, then mixed gas of helium and fluorescent powder is conveyed into the sealed space, and the fluorescent powder can be driven by the helium to penetrate through the inner wall of the oil storage tank along the tiny gaps to be attached to the outer surface of the oil storage tank.

Description

Technical Field

[0001] The present invention relates to the technical field of detection devices, and in particular to a pressure-maintaining and sealing detection device for an oil-immersed transformer. Background Art

[0002] An oil-immersed transformer is a transformer that uses oil as an insulating and cooling medium. Its main structure includes an iron core, windings, an oil tank, and a cooling device. The working principle of an oil-immersed transformer is the same as that of other transformers, both of which are based on the law of electromagnetic induction. When alternating current passes through the primary winding of the transformer, an alternating magnetic field is generated. The alternating magnetic field is transmitted to the secondary winding through the iron core, inducing an AC voltage in the secondary winding, thereby realizing voltage conversion. The oil-immersed transformer pressure-maintaining and sealing detection device is mainly used to detect the sealing performance of the transformer to ensure that there will be no oil leakage during operation. Its working principle is based on the stability monitoring of air pressure and oil pressure. By applying a certain pressure to the inside of the transformer and observing the pressure changes, it is judged whether the sealing performance meets the standards.

[0003] Existing pressure-maintaining and sealing detection devices for oil-immersed transformers are mainly used to detect the sealing condition of the oil tank part of the transformer. The pressure-maintaining and sealing detection is mainly performed by filling the oil tank with gas at a certain pressure and observing the pressure drop to determine leakage. However, during long-term operation of the transformer, the insulating oil will undergo oxidation reaction under the influence of high temperature, electric field and oxygen factors, generating sludge, acid and colloid aging products. These substances are sticky and easily deposited in the gaps. Since existing pressure-maintaining and sealing detection devices mostly determine the sealing of the oil tank by detecting pressure changes to detect whether there is oil leakage, oil stains clogging the gaps will hinder oil leakage and pressure release, and the gaps are difficult to find, making it impossible for the detection device to accurately detect the existence of the gaps, resulting in false negative results, that is, mistakenly believing that the oil tank is tightly sealed, when in fact there are hidden dangers of gaps, thereby affecting the normal operation of the transformer in the later stage.

[0004] Therefore, we propose an oil-immersed transformer pressure-maintaining and sealing detection device to solve the above-mentioned problems. Summary of the Invention

[0005] The purpose of the present invention is to provide an oil-immersed transformer pressure-maintaining and sealing detection device to solve the problem proposed in the above background technology that the tiny gaps blocked by oil pollution when detecting the sealing condition of the oil tank are difficult to detect and affect the subsequent operation.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a pressure-maintaining and sealing detection device for an oil-immersed transformer, comprising a transformer body, an oil storage tank being arranged on the outer surface of the transformer body, a preliminary survey component being arranged on the outer surface of the transformer body for preliminarily detecting whether there is slight damage on the inner wall of the oil storage tank, a deep cleaning component being arranged on the outer surface of the preliminary survey component for cleaning the inner wall of the oil storage tank, the deep cleaning component comprising a negative pressure chamber, two heating wires being arranged on the inner wall of the negative pressure chamber for heating and liquefying the solid oil on the inner wall of the oil storage tank, and the outer surface of the negative pressure chamber being close to the inner wall of the negative pressure chamber. A waste tank for collecting liquefied oil pollution by negative pressure adsorption is coupled near one side edge, and a marking component for displaying tiny cracks is provided on the outer surface of the negative pressure bin near the other side edge. The marking component includes a sealed tank for storing helium, and a leak box for storing fluorescent powder is provided on the inner wall of the sealed tank. A delivery pipe is fixedly connected to the outer surface of the sealed tank. When the helium is output to the outside through the sealed tank, the fluorescent powder in the leak box is driven by the pressure of the gas to mix with the helium and is delivered to the inside of the negative pressure bin through the delivery pipe, thereby marking the tiny damaged parts on the inner wall of the oil storage tank.

[0007] Preferably, the deep cleaning assembly also includes a first hydraulic rod, a lifting plate is fixedly installed on the top of the first hydraulic rod, two limiting tubes are slidably connected to the inner wall of the lifting plate, the bottoms of the two limiting tubes are fixedly connected to the top of the auxiliary plate, the outer surface of the first hydraulic rod is fixedly connected to the top of the auxiliary plate by screws, and a bent pipe is fixedly installed near the center of the top of the lifting plate.

[0008] Preferably, a servo motor is provided at the bottom end of the bent pipe, the output end of the servo motor is fixedly connected to a rotating shaft, the outer surface of the rotating shaft is fixedly sleeved with a connecting frame, the connecting frame is movably embedded with a connecting shaft, the outer surface of the connecting shaft is fixedly sleeved with a driven gear ring, the outer surface of the connecting frame is fixedly installed with a pressure-resistant frame, the inner wall of the pressure-resistant frame is provided with a stepper motor, and the output end of the stepper motor is fixedly connected to a positioning tube.

[0009] Preferably, one end of the positioning tube is movably embedded in the interior of the connecting frame, and an active gear ring is fixedly sleeved on the outer surface of the positioning tube. The outer surface of the active gear ring is meshed and connected with the outer surface of the driven gear ring. A second hydraulic rod is provided at the bottom of the connecting shaft, and the bottom end of the second hydraulic rod is fixedly connected to the top of the negative pressure bin, and the bottom end of the waste tank is fixedly connected to the outer surface of the negative pressure bin.

[0010] Preferably, a fan is provided inside the negative pressure bin through an auxiliary rod, a negative pressure pump is fixedly installed on the outer surface of one side of the negative pressure bin by screws, the input end of the negative pressure pump is fixedly connected to a negative pressure pipe, one end of the negative pressure pipe is fixedly passed through the interior of the negative pressure bin, and the output end of the negative pressure pump is fixedly connected to a recovery pipe, one end of the recovery pipe is fixedly passed through the interior of the waste tank.

[0011] Preferably, the bottom end of the sealed tank is fixedly connected to the outer surface of the negative pressure chamber by screws, a first cylinder is provided on the inner bottom surface of the sealed tank, a piston is fixedly connected to the top of the first cylinder, the piston is provided inside the sealed tank, and a pressure sensor is provided on the top of the piston.

[0012] Preferably, a second cylinder is provided on the inner wall of the sealing tank through an auxiliary block, a seal is fixed on the top of the second cylinder, the outer surface of the seal slides with the inner wall of the sealing tank, the bottom end of the delivery pipe is fixed and passes through the interior of the negative pressure chamber, and an electromagnetic valve is provided on the outer surface of the delivery pipe.

[0013] Preferably, the preliminary survey assembly includes a base frame, the transformer body is arranged on the top of the base frame, the outer surface of the base frame is fixedly connected to the outer surface of the auxiliary plate, a telescopic rod is fixed to the top of the base frame near one side edge, the top of the telescopic rod is fixedly connected to an arc frame, and a multi-stage electric push rod is arranged at the top of the base frame near the other side edge.

[0014] Preferably, the top of the multi-stage electric push rod is fixedly connected to the bottom of the arc frame, an arc-shaped rack is fixed to the top of the arc frame, the outer surface of the arc frame is slidably connected to a slide, the interior of the slide is coupled with a positioning rod, an infrared measuring instrument is provided at one end of the positioning rod, a gear is provided inside the slide, and a drive motor is fixedly installed on the outer surface of the slide by screws.

[0015] Preferably, the output end of the driving motor is fixedly connected to a driving shaft, and the two ends of the driving shaft are movable through the opposite outsides of the slide, the outer surface of the driving shaft is fixedly connected to the inner wall of the gear, the outer surface of the gear is meshed with the outer surface of the arc-shaped rack, and the outer surface of the slide slides with the inner wall of the arc-shaped frame.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. When the infrared measuring instrument detects a suspicious gap on the outer wall of the oil storage tank, the negative pressure chamber can be inserted into the oil storage tank and rotated in all directions to face the suspected tiny gap on the inner wall of the oil storage tank. The negative pressure chamber is moved to fit tightly with the inner wall of the oil storage tank, and the oil pollution at the location is cleaned by heating and negative pressure. Then, a mixed gas of helium and fluorescent powder is transported into the sealed space. Driven by the helium, the fluorescent powder will pass through the inner wall of the oil storage tank along the tiny gap and adhere to the outer surface of the oil storage tank. The staff can detect whether there is a tiny gap at the location by detecting whether there is fluorescent powder on the outer wall of the oil storage tank. This solves the problem in the prior art that the tiny gap blocked by oil pollution is difficult to detect when detecting the sealing condition of the oil-immersed transformer pressure-maintaining seal, which affects the subsequent operation.

[0018] 2. When inspecting the pressure-maintaining seal in the oil storage tank of an oil-immersed transformer, in order to prevent oil from clogging the gaps and making it impossible for the detection device to accurately detect the existence of the gaps, first start the drive motor and the multi-stage electric push rod to drive the infrared measuring instrument to rotate along the outer wall of the oil storage tank in all directions, and perform infrared measurement on the outer wall of the oil storage tank to detect whether there are any suspicious tiny gaps on the outer wall of the oil storage tank. This allows the staff to detect whether there are tiny gaps on the outer wall of the oil storage tank without having to conduct a comprehensive and accurate survey of the inner wall of the oil storage tank, which facilitates the subsequent detection tasks.

[0019] 3. In order to achieve sufficient mixing between helium and phosphor, when helium needs to be transported into the negative pressure chamber, the helium in the sealed tank is first pressurized. When the pressure sensor detects that the helium pressure in the sealed tank reaches the specified value, the seal and the leak box are separated, allowing the helium to mix with the phosphor through the leak box. The mixed helium and phosphor are transported outward along the delivery pipe under the action of the pressure difference, achieving sufficient mixing between the helium and phosphor and preventing insufficient phosphor delivery in the later stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a front perspective view of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0021] Figure 2 This is a partial perspective view of a preliminary survey component of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0022] Figure 3 A partial cutaway perspective view of a preliminary survey component of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0023] Figure 4 This is a partially cutaway perspective view of an arc-shaped rack of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0024] Figure 5A three-dimensional diagram of the oil tank portion of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0025] Figure 6 This is a partial perspective view of a deep cleaning component of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0026] Figure 7 A three-dimensional diagram of the negative pressure chamber portion of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0027] Figure 8 This is a perspective view of the structure of the compression frame of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0028] Figure 9 This is a three-dimensional diagram of the recovery pipe portion of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0029] Figure 10 A three-dimensional diagram of the fan portion of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0030] Figure 11 This is a partially cutaway perspective view of a waste tank of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention;

[0031] Figure 12 This is a perspective view of the expanded structure of a marking component of a pressure-maintaining and sealing detection device for an oil-immersed transformer according to the present invention.

[0032] In the picture:

[0033] 1. Transformer body; 2. Oil storage tank; 3. Preliminary survey assembly; 301. Base frame; 302. Telescopic rod; 303. Multi-stage electric push rod; 304. Arc frame; 305. Arc rack; 306. Slide; 307. Positioning rod; 308. Infrared measuring instrument; 309. Drive motor; 310. Drive shaft; 311. Gear; 4. Deep cleaning assembly; 401. First hydraulic rod; 402. Lifting plate; 403. Limiting tube; 404. Bend pipe; 405. Servo motor; 406. Rotating shaft; 407. Connecting frame; 408. Connecting shaft; 4 09. Driven gear ring; 410. Pressure-resistant frame; 411. Stepper motor; 412. Positioning tube; 413. Driven gear ring; 414. Waste tank; 415. Second hydraulic rod; 416. Negative pressure chamber; 417. Heating wire; 418. Fan; 419. Negative pressure pump; 420. Negative pressure tube; 421. Recovery tube; 5. Marking assembly; 501. Sealing tank; 502. First cylinder; 503. Piston; 504. Pressure sensor; 505. Second cylinder; 506. Seal; 507. Leak box; 508. Delivery tube; 509. Solenoid valve. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the implementation regulations described are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0035] See also Figure 1-Figure 4 The present invention provides a technical solution: a pressure-maintaining and sealing detection device for an oil-immersed transformer, wherein the preliminary survey component 3 includes a base frame 301, the transformer body 1 is arranged on the top of the base frame 301, the outer surface of the base frame 301 is fixedly connected to the outer surface of the auxiliary plate, a telescopic rod 302 is fixed to the top of the base frame 301 near one side edge, the top of the telescopic rod 302 is fixedly connected to an arc frame 304, a multi-stage electric push rod 303 is arranged at the top of the base frame 301 near the other side edge, the top of the multi-stage electric push rod 303 is fixedly connected to the bottom of the arc frame 304, an arc rack 305 is fixed to the top of the arc frame 304, and the outer surface of the arc frame 304 slides It is connected to a slide 306, and the internal coupling of the slide 306 is connected to a positioning rod 307. An infrared measuring instrument 308 is set at one end of the positioning rod 307. A gear 311 is set inside the slide 306. The outer surface of the slide 306 is fixed with a drive motor 309 by screws. The output end of the drive motor 309 is fixedly connected to a drive shaft 310. The two ends of the drive shaft 310 are respectively movable and penetrate to the opposite outside of the slide 306. The outer surface of the drive shaft 310 is fixedly connected to the inner wall of the gear 311. The outer surface of the gear 311 is meshed with the outer surface of the arc rack 305. The outer surface of the slide 306 slides with the inner wall of the arc frame 304.

[0036] In this embodiment, when testing the pressure-maintaining seal condition of the oil storage tank 2 of the oil-immersed transformer, firstly, a certain pressure of gas is filled into the oil storage tank 2 through an external pressure-maintaining seal testing device, and the pressure drop is observed to determine the leakage. In the process of testing the tiny gaps in the oil storage tank 2, in order to prevent the gaps from being blocked by oil and making it impossible for the detection device to accurately detect the existence of the gaps, the transformer body 1 is first placed in a position such as Figure 1The top of the base frame 301 shown in the figure is then started, and the driving motor 309 is driven to rotate the driving shaft 310, thereby driving the gear 311 to rotate, so that the gear 311 moves along the outer surface of the arc-shaped rack 305, and the infrared measuring instrument 308 is started to perform infrared measurement on the outer wall of the oil storage tank 2 through the infrared measuring instrument 308 to detect whether there are suspicious tiny gaps on the outer wall of the oil storage tank 2. When there are tiny gaps blocked by oil in the transformer oil storage tank 2, the heat conduction characteristics at the gap will change due to the presence of oil. The infrared measuring instrument 308 can still indirectly detect the temperature anomaly caused by the difference in local thermal resistance. When the gap is partially blocked, the oil does not completely fill the gap, and there are still tiny channels. At this time, the two sides of the gap will produce dynamic movement due to the penetration of oil. When the gap is completely sealed by oil and isolated from the internal oil, it only manifests as a static thermal resistance difference, forming a low-temperature spot, which can detect whether there is a tiny gap in the inner wall of the oil storage tank 2. When the measurement on the same horizontal line of the outer wall of the oil storage tank 2 is completed, the multi-stage electric push rod 303 can be started to extend or shorten it, driving the arc frame 304 to move upward or downward, thereby driving the external measuring instrument 308 to move upward or downward, and at the same time rotating along the outer wall of the oil storage tank 2 in all directions to measure whether there is a suspicious tiny gap in the outer wall of the oil storage tank 2. Through the function of the preliminary survey component 3, when the staff detects whether there is a tiny gap in the outer wall of the oil storage tank 2, there is no need to conduct a comprehensive and accurate survey of the inner wall of the oil storage tank 2, which facilitates the subsequent detection tasks.

[0037] like Figure 1 and Figure 5-Figure 12As shown, a pressure-maintaining and sealing detection device for an oil-immersed transformer comprises a transformer body 1, an oil storage tank 2 is arranged on the outer surface of the transformer body 1, a preliminary survey component 3 is arranged on the outer surface of the transformer body 1 for preliminarily detecting whether there is slight damage on the inner wall of the oil storage tank 2, a deep cleaning component 4 is arranged on the outer surface of the preliminary survey component 3 for cleaning the inner wall of the oil storage tank 2, the deep cleaning component 4 comprises a negative pressure chamber 416, two heating wires 417 are arranged on the inner wall of the negative pressure chamber 416 for heating and liquefying the solid oil on the inner wall of the oil storage tank 2, a waste tank 414 for negative pressure adsorption and collection of the liquefied oil is coupled to the outer surface of the negative pressure chamber 416 near one side edge, and a waste tank 414 for negatively adsorbing and collecting the liquefied oil is arranged on the outer surface of the negative pressure chamber 416 near the other side edge. The marking component 5 includes a sealed tank 501 for storing helium, and the inner wall of the sealed tank 501 is provided with a leak box 507 for storing fluorescent powder. The outer surface of the sealed tank 501 is fixedly connected with a delivery pipe 508. When the helium is output outward through the sealed tank 501, the fluorescent powder in the leak box 507 is mixed with the helium under the pressure of the gas and is delivered to the inside of the negative pressure chamber 416 through the delivery pipe 508 to mark the minor damage on the inner wall of the oil storage tank 2. The deep cleaning component 4 also includes a first hydraulic rod 401. The top of the first hydraulic rod 401 is fixedly installed with a lifting plate 402. The inner wall of the lifting plate 402 is slidably connected to two limiting tubes 403. The bottoms of the two limiting tubes 403 are fixed to the top of the auxiliary plate. The outer surface of the first hydraulic rod 401 is fixedly connected to the top of the auxiliary plate by screws, and a bent pipe 404 is fixedly installed near the center of the top of the lifting plate 402. A servo motor 405 is set at the bottom end of the bent pipe 404, and the output end of the servo motor 405 is fixedly connected to a rotating shaft 406. The outer surface of the rotating shaft 406 is fixedly sleeved with a connecting frame 407, and a connecting shaft 408 is movably embedded in the interior of the connecting frame 407. The outer surface of the connecting shaft 408 is fixedly sleeved with a driven gear ring 409, and an anti-pressure frame 410 is fixedly installed on the outer surface of the connecting frame 407. A stepping motor 411 is set on the inner wall of the anti-pressure frame 410. The output end of the stepping motor 411 is fixedly connected to a positioning tube 412, and one end of the positioning tube 412 is movably embedded in the connecting frame 40 7, the outer surface of the positioning tube 412 is fixedly sleeved with an active gear ring 413, the outer surface of the active gear ring 413 is meshed with the outer surface of the driven gear ring 409, a second hydraulic rod 415 is provided at the bottom of the connecting shaft 408, the bottom end of the second hydraulic rod 415 is fixedly connected to the top of the negative pressure bin 416, the bottom end of the waste tank 414 is fixedly connected to the outer surface of the negative pressure bin 416, a fan 418 is provided inside the negative pressure bin 416 through an auxiliary rod, a negative pressure pump 419 is fixedly installed on the outer surface of one side of the negative pressure bin 416 by screws, the input end of the negative pressure pump 419 is fixedly connected to a negative pressure pipe 420, one end of the negative pressure pipe 420 is fixedly passed through the interior of the negative pressure bin 416, and the output end of the negative pressure pump 419 is fixedly connected to a recovery pipe 421,One end of the recovery tube 421 is fixedly inserted into the interior of the waste tank 414. The bottom end of the sealed tank 501 is fixedly connected to the outer surface of the negative pressure chamber 416 via screws. A first cylinder 502 is provided on the inner bottom surface of the sealed tank 501. A piston 503 is fixedly connected to the top of the first cylinder 502. The piston 503 is arranged inside the sealed tank 501. A pressure sensor 504 is installed on the top of the piston 503. A second cylinder 505 is installed on the inner wall of the sealed tank 501 through an auxiliary block. A seal 506 is fixed to the top of the second cylinder 505. The outer surface of the seal 506 slides against the inner wall of the sealed tank 501. The bottom end of the delivery tube 508 is fixedly inserted into the interior of the negative pressure chamber 416. A solenoid valve 509 is installed on the outer surface of the delivery tube 508.

[0038] In this embodiment, when the infrared measuring instrument 308 detects that there is a gap in the outer wall of the oil storage tank 2, in order to accurately locate the gap and prevent oil from clogging and making it difficult to find, the staff can manually open the sealing cover on the top of the oil storage tank 2, and then start the first hydraulic rod 401 to shorten it, driving the negative pressure chamber 416 to move downward to the inside of the oil storage tank 2, and then start the servo motor 405 to drive the rotating shaft 406 to rotate, thereby driving the connecting frame 407 to rotate, and at the same time start the stepping motor 411 to drive the positioning tube 412 to rotate, thereby driving the active gear ring 413 to rotate, and the active gear ring The rotation of 413 drives the driven gear ring 409 to rotate, and then drives the connecting shaft 408 to rotate, thereby driving the negative pressure chamber 416 to rotate in all directions. When the opening of the negative pressure chamber 416 rotates to a position where there is a small gap facing the inner wall of the oil storage tank 2, the servo motor 405 and the stepper motor 411 can be turned off, and then the second hydraulic rod 415 is started to extend, driving the negative pressure chamber 416 to move toward the inner wall of the oil storage tank 2 until the outer surface of the negative pressure chamber 416 is tightly fitted with the inner wall of the oil storage tank 2. Then, the two heating wires 417 can be electrically connected to the external power supply and released outward. The heat increases the temperature in the closed space formed by the negative pressure chamber 416 and the interior of the oil storage tank 2, thereby heating and softening the solid oil stains attached to the inner wall of the oil storage tank 2, reducing the adhesion between the oil stains and the inner wall of the oil storage tank 2, and at the same time starting the fan 418 to accelerate the flow of hot air in the negative pressure chamber 416, and at the same time starting the negative pressure pump 419 to drive the negative pressure pipe 420 to extract gas into the interior of the negative pressure chamber 416, so that the negative pressure chamber 416 is in a negative pressure state, thereby causing the oil stains sealed in the negative pressure chamber 416 to enter the waste tank 4 along the negative pressure pipe 420 under the action of the negative pressure. 14 is collected inside, achieving the removal of dirt in suspicious locations and preventing the difficulty in detecting whether there are tiny gaps due to oil covering the tiny gaps. After the oil is cleaned, the first cylinder 502 can be started to extend, driving the piston 503 to move upward, thereby pressurizing the helium in the sealed tank 501. Helium uses its small molecular characteristics, high diffusion ability and low environmental background concentration to achieve accurate positioning of extremely small leaks. The characteristics of helium make it an ideal leak detection gas. The molecules are extremely small and can easily pass through tiny gaps. The diameter of a helium molecule is only 0.26nm, which is smaller than air molecules and can even pass through gaps of 1 to 10μm at the micron level. Helium is an inert gas and does not react with the insulating oil and metal materials in the oil storage tank 2. It will not produce condensation and deposition during the detection process, avoiding secondary damage to the equipment. When the pressure sensor 504 detects that the air pressure of the helium in the sealed tank 501 reaches the specified value, the first cylinder 502 can be closed. Among them, the working principle of the pressure sensor 504 to detect the pressure value in the sealed tank 501 is based on the deformation of the elastic element, converting the pressure signal into an electrical signal, and then outputting readable data through the signal processing circuit. It is an existing mature technology and will not be introduced in detail here. At the same time, the second cylinder 505 is started to shorten it, driving the seal 506 to move downward, separating it from the bottom of the leak box 507, and then allowing the helium in the sealed tank 501 to enter the interior through the small hole in the leak box 507 and mix with the phosphor in the leak box 507. The mixed helium and phosphor are mixed under the action of the pressure difference. The helium is then pumped outward along the delivery pipe 508, while the solenoid valve 509 is opened, allowing the mixed gas to enter the enclosed space formed by the negative pressure chamber 416 and the inner wall of the oil tank 2. If a tiny crack exists in the inner wall of the oil tank 2 at this point, the fluorescent powder, driven by the helium gas, will pass through the inner wall of the oil tank 2 along the tiny crack and adhere to the outer surface of the oil tank 2. The operator can then detect the presence of the tiny crack by detecting the presence of the fluorescent powder on the outer wall of the oil tank 2. The cooperation between the deep cleaning component 4 and the marking component 5 enables the oil-immersed transformer pressure-maintaining and sealing detection device to accurately detect and display tiny cracks in the oil tank 2 without requiring helium to be fully filled inside the oil tank 2. This reduces costs and prevents the difficulty of detecting tiny cracks blocked by oil contamination. This solves the problem in prior art oil-immersed transformer pressure-maintaining and sealing detection devices that, during the oil tank inspection process, can fail to detect tiny cracks blocked by oil contamination, thus affecting the subsequent normal operation of the transformer.

[0039] The use method and working principle of this device are as follows: when detecting the pressure-maintaining seal condition of the oil storage tank 2 of the oil-immersed transformer, firstly, a certain pressure of gas is filled into the oil storage tank 2 through the external pressure-maintaining seal detection equipment, and the pressure drop is observed to determine the leakage. In the process of detecting the tiny gap in the oil storage tank 2, in order to prevent the gap from being blocked by oil and making the detection device unable to accurately detect the existence of the gap, first, the transformer body 1 is placed in a place such as Figure 1The top of the base frame 301 shown in the figure is then turned on to start the driving motor 309, which drives the driving shaft 310 to rotate, and then drives the gear 311 to rotate, so that the gear 311 moves along the outer surface of the arc-shaped rack 305. The outer wall of the oil storage tank 2 is infrared measured by the infrared measuring instrument 308 to detect whether there are small gaps in the outer wall of the oil storage tank 2. When there are small gaps blocked by oil in the transformer oil storage tank 2, the heat conduction characteristics at the gap will change due to the presence of oil. The infrared measuring instrument 308 can still indirectly detect the temperature anomaly caused by the difference in local thermal resistance. When the gap is partially blocked, the oil is The gap is not completely filled and there are still tiny channels. At this time, dynamic thermal effects will be generated on both sides of the gap due to oil penetration. When the gap is completely closed by oil and isolated from the internal oil, it will only show a static thermal resistance difference, forming a low-temperature spot, which can detect whether there is a tiny gap on the inner wall of the oil storage tank 2. When the measurement on the same horizontal line on the outer wall of the oil storage tank 2 is completed, the multi-stage electric push rod 303 can be started to extend or shorten it, driving the arc frame 304 to move upward or downward, and then driving the external measuring instrument 308 to move upward or downward, and at the same time rotate along the outer wall of the oil storage tank 2 in all directions to measure whether the outer wall of the oil storage tank 2 is There is a tiny gap, so when the staff detects whether there is a tiny gap on the outer wall of the oil storage tank 2, there is no need to conduct a comprehensive and accurate survey of the inner wall of the oil storage tank 2. When the infrared measuring instrument 308 detects that there is a tiny gap on the outer wall of the oil storage tank 2, the staff can manually open the sealing cover on the top of the oil storage tank 2, and then start the first hydraulic rod 401 to shorten it, driving the negative pressure chamber 416 to move downward to the inside of the oil storage tank 2, and then start the servo motor 405 to drive the rotating shaft 406 to rotate, thereby driving the connecting frame 407 to rotate, and at the same time start the stepping motor 411 to drive the positioning tube 412 to rotate, thereby driving the negative pressure chamber 416 to move downward to the inside of the oil storage tank 2. The active gear ring 413 rotates, and the rotation of the active gear ring 413 drives the driven gear ring 409 to rotate, and then drives the connecting shaft 408 to rotate, thereby driving the negative pressure chamber 416 to rotate in all directions. When the opening of the negative pressure chamber 416 rotates to a position where there is a small gap facing the inner wall of the oil storage tank 2, the servo motor 405 and the stepper motor 411 can be closed. Among them, the servo motor 405 and the stepper motor 411 both have a self-locking function, and then the second hydraulic rod 415 is started to extend, driving the negative pressure chamber 416 to move toward the inner wall of the oil storage tank 2 until the outer surface of the negative pressure chamber 416 is tightly fitted with the inner wall of the oil storage tank 2. Figure 10As shown, a sealing ring is provided at the position where the negative pressure chamber 416 contacts the inner wall of the oil storage tank 2. The sealing ring is made of rubber material and has strong sealing performance, thereby improving the sealing strength between the negative pressure chamber 416 and the inner wall of the oil storage tank 2. Then, the two heating wires 417 can be electrically connected to the external power supply respectively to release heat outward, thereby increasing the temperature in the closed space formed by the negative pressure chamber 416 and the interior of the oil storage tank 2, thereby heating and softening the solid oil attached to the inner wall of the oil storage tank 2, reducing the adhesion between the oil and the inner wall of the oil storage tank 2, and at the same time starting the fan 418 to accelerate the flow of hot air in the negative pressure chamber 416, and at the same time starting the negative pressure pump 419 to drive the negative pressure pipe 42 0 extracts gas from the negative pressure chamber 416, so that the negative pressure chamber 416 is in a negative pressure state, so that the oil and dirt sealed in the negative pressure chamber 416 enter the waste tank 414 along the negative pressure pipe 420 under the action of negative pressure for collection. After the oil and dirt are cleaned, the first cylinder 502 can be started to extend, driving the piston 503 to move upward, thereby pressurizing the helium in the sealed tank 501. Helium uses its small molecular characteristics, high diffusion ability and low environmental background concentration to achieve accurate positioning of extremely small leaks. The characteristics of helium make it an ideal leak detection gas. The molecules are extremely small and can easily pass through tiny gaps. The diameter of helium molecules is only 0.26nm. It is smaller than air molecules and can even pass through gaps of 1 to 10 μm in the micron level. Helium is an inert gas and does not react with the insulating oil and metal materials in the oil storage tank 2. It will not produce condensation and deposition during the detection process, thus avoiding secondary damage to the equipment. When the pressure sensor 504 detects that the helium pressure in the sealed tank 501 reaches the specified value, the first cylinder 502 can be closed and the second cylinder 505 can be started to shorten it, driving the seal 506 to move downward and separate it from the bottom of the leak box 507, thereby allowing the helium in the sealed tank 501 to enter the interior through the small hole in the leak box 507 and mix with the phosphor in the leak box 507. The mixed helium and fluorescent powder are transported outward along the delivery pipe 508 under the action of the pressure difference, and the solenoid valve 509 is opened at the same time, allowing the mixed gas to enter the enclosed space formed by the negative pressure chamber 416 and the inner wall of the oil storage tank 2. If there is a tiny gap in the inner wall of the oil storage tank 2 at this time, the fluorescent powder will pass through the inner wall of the oil storage tank 2 along the tiny gap under the drive of the helium gas and adhere to the outer surface of the oil storage tank 2. The staff can detect whether there is a tiny gap at this location by detecting whether there is fluorescent powder on the outer wall of the oil storage tank 2. Through the cooperation between the deep cleaning component 4 and the marking component 5, the oil-immersed transformer pressure-maintaining seal detection device can accurately detect tiny gaps in the oil storage tank 2.

[0040] The wiring diagram of the transformer body 1, the multi-stage electric push rod 303, the infrared measuring instrument 308, the drive motor 309, the first hydraulic rod 401, the stepping motor 411, the second hydraulic rod 415, the heating wire 417, the fan 418, the negative pressure pump 419, the first cylinder 502, the pressure sensor 504, the second cylinder 505 and the solenoid valve 509 in the present invention is common knowledge in the art, and its working principle is a well-known technology. The model is selected according to the actual use. Therefore, the control method and wiring arrangement of the transformer body 1, the multi-stage electric push rod 303, the infrared measuring instrument 308, the drive motor 309, the first hydraulic rod 401, the stepping motor 411, the second hydraulic rod 415, the heating wire 417, the fan 418, the negative pressure pump 419, the first cylinder 502, the pressure sensor 504, the second cylinder 505 and the solenoid valve 509 are no longer explained in detail.

[0041] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pressure-maintaining and sealing detection device for an oil-immersed transformer, comprising a transformer body (1), an oil storage tank (2) provided on the outer surface of the transformer body (1), and a preliminary survey component (3) provided on the outer surface of the transformer body (1) for preliminary detecting whether the inner wall of the oil storage tank (2) has minor damage, characterized in that: The outer surface of the preliminary survey component (3) is provided with a deep cleaning component (4) for cleaning the inner wall of the oil storage tank (2), and the deep cleaning component (4) includes a negative pressure chamber (416). The inner wall of the negative pressure chamber (416) is provided with two heating wires (417) for heating and liquefying the solid oil on the inner wall of the oil storage tank (2). The outer surface of the negative pressure chamber (416) is coupled with a waste tank (414) for collecting the liquefied oil by negative pressure adsorption near one side edge. A marking assembly (5) for displaying minute cracks is provided on the outer surface of the negative pressure chamber (416) near the other side edge. The marking assembly (5) includes a sealed tank (501) for storing helium. A leak box (507) for storing fluorescent powder is provided on the inner wall of the sealed tank (501). A delivery pipe (508) is fixedly connected to the outer surface of the sealed tank (501). When the helium is output through the sealed tank (501), the fluorescent powder in the leak box (507) is mixed with the helium under the pressure of the gas and is delivered to the interior of the negative pressure chamber (416) through the delivery pipe (508), thereby marking the minute damaged portion of the inner wall of the oil storage tank (2).

2. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 1, characterized in that: The deep cleaning assembly (4) further comprises a first hydraulic rod (401), a lifting plate (402) being fixedly mounted on the top of the first hydraulic rod (401), two limiting tubes (403) being slidably connected to the inner wall of the lifting plate (402), the bottoms of the two limiting tubes (403) being fixedly connected to the top of the auxiliary plate, the outer surface of the first hydraulic rod (401) being fixedly connected to the top of the auxiliary plate via screws, and a curved tube (404) being fixedly mounted near the center of the top of the lifting plate (402).

3. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 2, characterized in that: A servo motor (405) is provided at the bottom end of the curved pipe (404), the output end of the servo motor (405) is fixedly connected to a rotating shaft (406), the outer surface of the rotating shaft (406) is fixedly sleeved with a connecting frame (407), the interior of the connecting frame (407) is movably embedded with a connecting shaft (408), the outer surface of the connecting shaft (408) is fixedly sleeved with a driven gear ring (409), the outer surface of the connecting frame (407) is fixedly installed with a pressure-resistant frame (410), the inner wall of the pressure-resistant frame (410) is provided with a stepping motor (411), and the output end of the stepping motor (411) is fixedly connected to a positioning tube (412).

4. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 3, characterized in that: One end of the positioning tube (412) is movably embedded in the interior of the connecting frame (407); an active gear ring (413) is fixedly sleeved on the outer surface of the positioning tube (412); the outer surface of the active gear ring (413) is meshedly connected with the outer surface of the driven gear ring (409); a second hydraulic rod (415) is provided at the bottom of the connecting shaft (408); the bottom end of the second hydraulic rod (415) is fixedly connected to the top of the negative pressure chamber (416); and the bottom end of the waste tank (414) is fixedly connected to the outer surface of the negative pressure chamber (416).

5. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 4, characterized in that: A fan (418) is provided inside the negative pressure bin (416) via an auxiliary rod, a negative pressure pump (419) is fixedly installed on the outer surface of one side of the negative pressure bin (416) via screws, an input end of the negative pressure pump (419) is fixedly connected to a negative pressure pipe (420), one end of the negative pressure pipe (420) is fixedly passed through the inside of the negative pressure bin (416), an output end of the negative pressure pump (419) is fixedly connected to a recovery pipe (421), one end of the recovery pipe (421) is fixedly passed through the inside of the waste tank (414).

6. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 5, characterized in that: The bottom end of the sealed tank (501) is fixedly connected to the outer surface of the negative pressure chamber (416) by screws, and a first cylinder (502) is provided on the inner bottom surface of the sealed tank (501). The top end of the first cylinder (502) is fixedly connected to a piston (503), and the piston (503) is provided inside the sealed tank (501). A pressure sensor (504) is provided on the top of the piston (503).

7. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 6, characterized in that: The inner wall of the sealing tank (501) is provided with a second cylinder (505) through an auxiliary block, and a sealing member (506) is fixed to the top of the second cylinder (505). The outer surface of the sealing member (506) slides with the inner wall of the sealing tank (501), and the bottom end of the delivery pipe (508) is fixed to the interior of the negative pressure chamber (416), and an electromagnetic valve (509) is provided on the outer surface of the delivery pipe (508).

8. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 7, characterized in that: The preliminary survey assembly (3) comprises a base frame (301), the transformer body (1) is arranged on the top of the base frame (301), the outer surface of the base frame (301) is fixedly connected to the outer surface of the auxiliary plate, a telescopic rod (302) is fixed on the top of the base frame (301) near one side edge, the top end of the telescopic rod (302) is fixedly connected to an arc frame (304), and a multi-stage electric push rod (303) is arranged on the top of the base frame (301) near the other side edge.

9. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 8, characterized in that: The top of the multi-stage electric push rod (303) is fixedly connected to the bottom of the arc frame (304), an arc rack (305) is fixed to the top of the arc frame (304), the outer surface of the arc frame (304) is slidably connected to a slide (306), the interior of the slide (306) is coupled and connected to a positioning rod (307), one end of the positioning rod (307) is provided with an infrared measuring instrument (308), a gear (311) is provided inside the slide (306), and a driving motor (309) is fixedly installed on the outer surface of the slide (306) by screws.

10. The oil-immersed transformer pressure-maintaining and sealing detection device according to claim 9, characterized in that: The output end of the driving motor (309) is fixedly connected to a driving shaft (310), and the two ends of the driving shaft (310) are movable and penetrate the opposite exteriors of the slide (306). The outer surface of the driving shaft (310) is fixedly connected to the inner wall of the gear (311), and the outer surface of the gear (311) is meshedly connected to the outer surface of the arc-shaped rack (305). The outer surface of the slide (306) slides with the inner wall of the arc-shaped frame (304).

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