Vacuum-pumping equipment for transformer

Abstract

The utility model discloses a transformer vacuum-pumping device which comprises an air-pumping main pipe, a first-stage pump, a second-stage pump, a third-stage pump, an oil-gas separator and a vacuum gauge are sequentially connected in series from the upstream end to the downstream end of the air-pumping main pipe, and a first bypass pipe connected with the second-stage pump in parallel and a second bypass pipe connected with the third-stage pump in parallel are further arranged on the air-pumping main pipe. The first bypass pipe is provided with a first electromagnetic valve, the second bypass pipe is provided with a second electromagnetic valve, the first-stage pump is a rotary vane pump or a screw pump, the second-stage pump is a roots pump, and the third-stage pump is a molecular pump. Firstly, a first-stage pump is started to pump the interior of a transformer oil tank to a first set vacuum pressure value, then a second-stage pump is started to pump to a second set vacuum pressure value, and finally a third-stage pump is started to pump to a set target vacuum pressure value, so that water and dissolved gas remaining in an insulating plate and transformer oil are pumped out; the extracted gas enters the pump set after oil is separated through the oil-gas separator, pollution to the main gas extraction pipe and the pump set is effectively avoided or relieved, and the service life of the vacuumizing equipment is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of vacuum pumping unit technology, specifically to a transformer vacuum pumping device. Background Technology

[0002] In modern power substation industry, vacuum pumping units have become key technical equipment for ensuring the manufacturing quality and operational reliability of power equipment. As power systems develop towards higher voltage and larger capacity, higher requirements are placed on the insulation performance of critical equipment such as transformers and circuit breakers, making vacuum processing technology increasingly important in this field.

[0003] In traditional power equipment manufacturing processes, insulation material treatment mainly relies on methods such as hot air circulation drying and natural exhaust. However, these technologies have drawbacks such as incomplete drying, long processing cycles, and high energy consumption. Taking large oil-immersed transformers as an example, the residual moisture and dissolved gases in their insulation boards and transformer oil can easily cause partial discharge under operating voltage, seriously affecting equipment life and power grid safety. Therefore, when injecting transformer oil after installation, large oil-immersed transformers need to have their tanks evacuated to remove moisture and dissolved gases from the insulation materials and transformer oil.

[0004] Existing vacuum pumping units used for evacuating transformer oil tanks are mostly rotary vane pump units. When using this unit to evacuate the transformer oil tank, the free end of the pumping pipe is connected to the air outlet at the top of the transformer oil tank, and then the vacuum pumping unit is started to evacuate the transformer oil tank to a certain vacuum pressure. The problem with using this vacuum pumping unit for evacuating the transformer oil tank is that the pressure inside the transformer oil tank drops sharply. This evacuation process mainly removes the air above the transformer oil surface, but it is difficult to further remove moisture and dissolved gases remaining in the insulation plates or inside the transformer oil. If the operating power of the vacuum pumping unit is forcibly increased, the vacuum level inside the transformer oil tank will drop sharply, causing a large amount of transformer oil to vaporize and enter the pumping pipe and the vacuum pumping unit, causing contamination to both. Therefore, this utility model proposes a transformer vacuuming device to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this invention is to overcome the deficiencies in the existing technology and provide a transformer vacuuming device. By sequentially connecting a primary pump, a secondary pump, and a tertiary pump at the upstream end of the main vacuum pipe, the vacuuming operation can be carried out in stages. In operation, the primary pump is first activated to pump the internal cavity of the transformer tank to a first set vacuum pressure value, thereby removing as much air as possible from the upper space of the transformer tank. Next, the secondary pump is activated to pump the internal cavity of the transformer tank to a second set vacuum pressure value. Finally, the tertiary pump is activated, with the three pump groups working together to pump the internal cavity of the transformer tank to the set target vacuum pressure value. This removes residual moisture and dissolved gases from the insulation board and transformer oil, ensuring good transformer performance. The gas extracted from the internal cavity of the transformer tank passes through an oil-gas separator to separate oil before entering the pump group upstream of the main vacuum pipe, effectively avoiding or mitigating contamination of the main vacuum pipe and pump group, thus helping to extend the service life of this transformer vacuuming device. Simultaneously, it significantly reduces energy consumption, helps save costs, and facilitates widespread application.

[0006] To achieve the above objectives, the technical solution of this utility model is to design a transformer vacuum pumping device, including a main pumping pipe. From upstream to downstream, a primary pump, a secondary pump, a tertiary pump, an oil-gas separator, and a vacuum gauge are connected in series on the main pumping pipe. The upstream end of the main pumping pipe also has a first bypass pipe connected in parallel with the secondary pump and a second bypass pipe connected in parallel with the tertiary pump. The first bypass pipe is equipped with a solenoid valve one, and the second bypass pipe is equipped with a solenoid valve two. The primary pump is either a rotary vane pump or a screw pump, the secondary pump is a Roots pump, and the tertiary pump is a molecular pump. The primary pump, secondary pump, tertiary pump, vacuum gauge, oil-gas separator, solenoid valve one, and solenoid valve two are all electrically connected to a control system.

[0007] This utility model discloses a transformer vacuum pumping device. By sequentially connecting a primary pump, a secondary pump, and a tertiary pump at the upstream end of the main pumping pipe, the vacuum pumping operation can be carried out in stages. In operation, the primary pump is first activated to pump the internal cavity of the transformer tank to a first set vacuum pressure value, thereby removing as much air as possible from the upper space of the transformer tank. Next, the secondary pump is activated to pump the internal cavity of the transformer tank to a second set vacuum pressure value. Finally, the tertiary pump is activated, with the three pump sets working together to pump the internal cavity of the transformer tank to the set target vacuum pressure value. This process removes residual moisture and dissolved gases from the insulation board and transformer oil, ensuring good transformer performance. The gas extracted from the internal cavity of the transformer tank passes through an oil-gas separator to separate oil before entering the pump set upstream of the main pumping pipe, effectively avoiding or mitigating contamination of the main pumping pipe and pump set, thus extending the service life of this transformer vacuum pumping device. Simultaneously, it significantly reduces energy consumption, helps save costs, and facilitates widespread application.

[0008] A preferred technical solution is that the downstream end of the main extraction pipe is connected to several extraction branch pipes via multi-port connectors, and each extraction branch pipe has a quick-connect fitting at its free end. In use, the quick-connect fittings at the free ends of the extraction branch pipes can be connected one-to-one to multiple interfaces on the transformer tank, thereby allowing the internal cavity of the transformer tank to be pumped to the set target vacuum pressure more quickly, which helps improve the overall extraction efficiency.

[0009] A further preferred technical solution is that at least two primary pumps are arranged in parallel, and the air inlet of each primary pump is connected to the upstream end of the main suction pipe through a bypass pipe. The bypass pipe is equipped with a solenoid valve three electrically connected to the control system. The parallel arrangement of at least two primary pumps allows for a backup system, ensuring that if one primary pump fails, the other can still guarantee the normal operation of the transformer vacuuming equipment of this invention. Furthermore, when simultaneously vacuuming multiple transformer tanks, the transformer vacuuming equipment of this invention can activate multiple primary pumps to meet the requirements of the first set vacuum pressure value or the target vacuum pressure value.

[0010] A further preferred technical solution involves having two secondary and three tertiary pumps arranged in parallel. One secondary pump is located on the main suction pipe, and the other is connected in parallel to the main suction pipe via a third bypass pipe. Similarly, one tertiary pump is located on the main suction pipe, and the other is connected in parallel to the main suction pipe via a fourth bypass pipe. The inlet of the secondary pump is equipped with a manual valve one, and the inlet of the tertiary pump is equipped with a manual valve two. Having at least two secondary and three tertiary pumps arranged in parallel allows for backup operation, ensuring that if one secondary or tertiary pump fails, the other can still guarantee the normal operation of the transformer vacuum pumping equipment of this invention.

[0011] A further preferred technical solution is that the multi-port connector is one of a three-way valve, a four-way valve, or a five-way valve. This allows for the smooth installation of several extraction branch pipes downstream of the main extraction pipe.

[0012] A further preferred technical solution is that the oil-gas separator is equipped with a level gauge, and a drain valve is installed on the drain pipe located below the bottom of the oil-gas separator. The level gauge allows operators to observe the level of oil accumulated at the bottom of the oil-gas separator in real time and to promptly drain the oil, preventing oil spills from occurring.

[0013] A further preferred technical solution is that the main exhaust pipe is also equipped with an oil mist filter located between the three-stage pump and the oil-gas separator. The oil mist filter performs secondary filtration of oil in the gas entering the upstream end of the main exhaust pipe and the pump assembly, thereby further preventing oil from contaminating the main exhaust pipe and the pump assembly.

[0014] The advantages and beneficial effects of this utility model are as follows:

[0015] 1. This utility model discloses a transformer vacuum pumping device. By sequentially connecting a primary pump, a secondary pump, and a tertiary pump at the upstream end of the main pumping pipe, the pumping operation can be carried out in stages. In operation, the primary pump is first activated to pump the internal cavity of the transformer tank to a first set vacuum pressure value, thereby removing as much air as possible from the upper space of the transformer tank. Next, the secondary pump is activated to pump the internal cavity of the transformer tank to a second set vacuum pressure value. Finally, the tertiary pump is activated, with the three pump sets working together to pump the internal cavity of the transformer tank to the set target vacuum pressure value. This process removes residual moisture and dissolved gases from the insulation board and transformer oil, ensuring good transformer performance. The gas extracted from the internal cavity of the transformer tank passes through an oil-gas separator to separate oil before entering the pump set upstream of the main pumping pipe, effectively avoiding or mitigating contamination of the main pumping pipe and pump set, thus extending the service life of this transformer vacuum pumping device. Simultaneously, it significantly reduces energy consumption, helps save costs, and facilitates widespread application.

[0016] 2. The downstream end of the main extraction pipe is connected to several extraction branch pipes via multi-port connectors, and each extraction branch pipe has a quick-connect fitting at its free end. In use, the quick-connect fittings at the free ends of the extraction branch pipes can be connected one-to-one with multiple interfaces on the transformer tank, thereby allowing the internal cavity of the transformer tank to be pumped to the set target vacuum pressure value more quickly, which helps to improve the overall extraction efficiency.

[0017] 3. At least two primary pumps are arranged in parallel to achieve the purpose of one being used as a backup. Thus, if one primary pump fails, the other primary pump can still ensure that the transformer vacuuming equipment of this utility model can operate normally. In addition, when the transformer vacuuming equipment of this utility model is used to vacuum multiple transformer tanks at the same time, multiple primary pumps can be started to meet the requirements of the first set vacuum pressure value or the target vacuum pressure value.

[0018] 4. At least two secondary and tertiary pumps are installed side by side to achieve the purpose of one being used as a backup. Thus, if one secondary or tertiary pump fails, the other secondary or tertiary pump can still ensure that the transformer vacuum pumping equipment of this utility model can still operate normally.

[0019] 5. The oil-gas separator is equipped with a level gauge, and a drain valve is installed on the drain pipe located below the bottom of the oil-gas separator. The level gauge allows operators to observe the level of oil accumulated at the bottom of the oil-gas separator in real time and to promptly drain the oil, preventing oil spill accidents.

[0020] 6. The main exhaust pipe is also equipped with an oil mist filter located between the three-stage pump and the vacuum gauge. The oil mist filter performs secondary filtration of oil in the gas entering the upstream end of the main exhaust pipe and the pump assembly, thereby further preventing oil from contaminating the main exhaust pipe and the pump assembly. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a transformer vacuum pumping device in Example 1;

[0022] Figure 2 This is a schematic diagram of the structure of a transformer vacuum pumping device in Embodiment 2;

[0023] Figure 3 This is a schematic diagram of a transformer vacuum pumping device in Example 3.

[0024] In the diagram: 1. Main extraction pipe; 2. Primary pump; 3. Secondary pump; 4. Tertiary pump; 5. Vacuum gauge; 6. Multi-port connector; 7. Extraction branch pipe; 8. Quick-connect fitting; 9. Oil-gas separator; 10. Oil mist filter; 1-1. First bypass pipe; 1-2. Second bypass pipe; 1-3. Extraction bypass pipe; 1-4. Third bypass pipe; 1-5. Fourth bypass pipe; 9-1. Level gauge; 9-2. Drain valve; a. Solenoid valve one; b. Solenoid valve two; c. Solenoid valve three; d. Manual valve one; e. Manual valve two. Detailed Implementation

[0025] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0026] Example 1

[0027] like Figure 1 As shown, a transformer vacuum pumping device includes a main pumping pipe 1. From upstream to downstream, a primary pump 2, a secondary pump 3, a tertiary pump 4, an oil-gas separator 9, and a vacuum gauge 5 are connected in series on the main pumping pipe 1. The upstream end of the main pumping pipe 1 also has a first bypass pipe 1-1 connected in parallel with the secondary pump 3 and a second bypass pipe 1-2 connected in parallel with the tertiary pump 4. The first bypass pipe 1-1 is equipped with a solenoid valve a, and the second bypass pipe 1-2 is equipped with a solenoid valve b. The primary pump 2 is either a rotary vane pump or a screw pump, the secondary pump 3 is a Roots pump, and the tertiary pump 4 is a molecular pump. The primary pump 2, secondary pump 3, tertiary pump 4, vacuum gauge 5, oil-gas separator 9, solenoid valve a, and solenoid valve b are all electrically connected to a control system.

[0028] Preferably, the downstream end of the main exhaust pipe 1 is connected to several exhaust branch pipes 7 via a multi-port connector 6, and each exhaust branch pipe 7 has a quick-connect connector 8 at its free end.

[0029] More preferably, the multi-port connector 6 is one of a three-way valve, a four-way valve, or a five-way valve.

[0030] More preferably, the oil-gas separator 9 is equipped with a level gauge 9-1, and the vent pipe located below the bottom of the oil-gas separator 9 is equipped with a vent valve 9-2.

[0031] Example 2

[0032] like Figure 2 As shown, a transformer vacuuming device differs from the transformer vacuuming device in Embodiment 1 in that: at least two primary pumps 2 are arranged in parallel, and the air inlet of each primary pump 2 is connected to the upstream end of the main pump 1 through a bypass pipe 1-3, and a solenoid valve 3c electrically connected to the control system is provided on the bypass pipe 1-3.

[0033] Example 3

[0034] like Figure 3 As shown, a transformer vacuuming device differs from the transformer vacuuming device in Embodiment 2 in that: two secondary pumps 3 and two tertiary pumps 4 are respectively arranged in parallel. One secondary pump 3 is located on the main suction pipe 1, and the other secondary pump 3 is connected in parallel to the main suction pipe 1 through a third bypass pipe 1-4. One tertiary pump 4 is located on the main suction pipe 1, and the other tertiary pump 4 is connected in parallel to the main suction pipe 1 through a fourth bypass pipe 1-5. The air inlet of the secondary pump 3 is equipped with a manual valve 1d, and the air inlet of the tertiary pump 4 is equipped with a manual valve 2e. In use, the manual valve corresponding to the secondary pump 3 or tertiary pump 4 that needs to be operated is opened, and the manual valve of the idle secondary pump 3 or tertiary pump 4 is closed.

[0035] Preferably, the main exhaust pipe 1 is further provided with an oil mist filter 10 located between the three-stage pump 4 and the oil-gas separator 9.

[0036] The working principle of a transformer vacuum pumping device in Examples 1-3:

[0037] In use, the quick-connect fittings 8 at the free ends of several air extraction branch pipes 7 are connected one by one to the multiple interfaces on the top of the transformer oil tank. First, the primary pump 2 is started to pump the internal cavity of the transformer oil tank to the first set vacuum pressure value so that the air in the upper space of the transformer oil tank is extracted as much as possible. Then, the secondary pump 3 is started to pump the internal cavity of the transformer oil tank to the second set vacuum pressure value. Finally, the tertiary pump 4 is started so that the three pump sets work together to pump the internal cavity of the transformer oil tank to the set target vacuum pressure value, thereby extracting the moisture and dissolved gas remaining in the insulation board and transformer oil.

[0038] Alternatively, the quick-connect fittings 8 at the free ends of several vacuum branch pipes 7 can be connected one by one to the interfaces on the top of multiple transformer oil tanks to perform simultaneous vacuuming operations on multiple transformer oil tanks.

[0039] This utility model discloses a transformer vacuum pumping device. By sequentially connecting a primary pump, a secondary pump, and a tertiary pump at the upstream end of the main pumping pipe, the vacuum pumping operation can be carried out in stages. In operation, the primary pump is first activated to pump the internal cavity of the transformer tank to a first set vacuum pressure value, thereby removing as much air as possible from the upper space of the transformer tank. Next, the secondary pump is activated to pump the internal cavity of the transformer tank to a second set vacuum pressure value. Finally, the tertiary pump is activated, with the three pump sets working together to pump the internal cavity of the transformer tank to the set target vacuum pressure value. This process removes residual moisture and dissolved gases from the insulation board and transformer oil, ensuring good transformer performance. The gas extracted from the internal cavity of the transformer tank passes through an oil-gas separator to separate oil before entering the pump set upstream of the main pumping pipe, effectively avoiding or mitigating contamination of the main pumping pipe and pump set, thus extending the service life of this transformer vacuum pumping device. Simultaneously, it significantly reduces energy consumption, helps save costs, and facilitates widespread application.

[0040] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A transformer vacuum pumping device, characterized in that, The system includes a main exhaust pipe (1), on which a primary pump (2), a secondary pump (3), a tertiary pump (4), an oil-gas separator (9), and a vacuum gauge (5) are connected in series from upstream to downstream. The main exhaust pipe (1) is also equipped with a first bypass pipe (1-1) connected in parallel with the secondary pump (3) and a second bypass pipe (1-2) connected in parallel with the tertiary pump (4). The first bypass pipe (1-1) is equipped with a solenoid valve (a) and the second bypass pipe (1-2) is equipped with a solenoid valve (b). The primary pump (2) is either a rotary vane pump or a screw pump. The secondary pump (3) is a Roots pump. The tertiary pump (4) is a molecular pump. The primary pump (2), the secondary pump (3), the tertiary pump (4), the vacuum gauge (5), the oil-gas separator (9), the solenoid valve (a), and the solenoid valve (b) are all electrically connected to the control system.

2. The transformer vacuuming equipment as described in claim 1, characterized in that, The downstream end of the main exhaust pipe (1) is connected to several exhaust branch pipes (7) through a multi-port connector (6), and each exhaust branch pipe (7) has a quick-connect connector (8) at its free end.

3. The transformer vacuuming equipment as described in claim 2, characterized in that, At least two primary pumps (2) are arranged in parallel. The air inlet of each primary pump (2) is connected to the upstream end of the main exhaust pipe (1) through the exhaust bypass pipe (1-3), and the exhaust bypass pipe (1-3) is equipped with a solenoid valve three (c) that is electrically connected to the control system.

4. The transformer vacuuming equipment as described in claim 3, characterized in that, The two-stage pump (3) and the three-stage pump (4) are arranged in parallel. One two-stage pump (3) is located on the main exhaust pipe (1), and the other two-stage pump (3) is connected in parallel to the main exhaust pipe (1) through the third bypass pipe (1-4). One three-stage pump (4) is located on the main exhaust pipe (1), and the other three-stage pump (4) is connected in parallel to the main exhaust pipe (1) through the fourth bypass pipe (1-5). The air inlet of the two-stage pump (3) is equipped with a manual valve one (d), and the air inlet of the three-stage pump (4) is equipped with a manual valve two (e).

5. The transformer vacuuming equipment as described in claim 4, characterized in that, The multi-port connector (6) is one of a three-way valve, a four-way valve, or a five-way valve.

6. The transformer vacuuming equipment as described in claim 5, characterized in that, The oil-gas separator (9) is equipped with a level gauge (9-1), and an air vent valve (9-2) is provided on the vent pipe located below the bottom of the oil-gas separator (9).

7. The transformer vacuuming equipment as described in any one of claims 1 to 6, characterized in that, The main exhaust pipe (1) is also equipped with an oil mist filter (10) located between the three-stage pump (4) and the oil-gas separator (9).

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