JP2020187058A - Oil collection device - Google Patents

Abstract

To provide an oil collection device capable of collecting an insulation oil while preventing aeration in the device.SOLUTION: An oil collection device 10 collects an insulation oil 4 of an electric device 1 whose inside 2a is filled with the insulation oil 4 and includes a first inactive gas 5. The oil collection device 10 includes a recovery container 31 for storing the collected insulation oil 4 through a storage path 25. Before the insulation oil 4 is collected, the storage path 25 and an inside 31a of the recovery container 31 are in a vacuum state after being filled with a second inactive gas 71.SELECTED DRAWING: Figure 11

Description

The present invention relates to an oil extraction device, and more particularly to an oil extraction device that collects insulating oil filled inside an electric power device.

In electric power equipment such as transformers in which the coil inside the equipment is filled with insulating oil, the volume of insulating oil changes due to changes in the temperature of the transformer. Therefore, by enclosing nitrogen gas (inert gas) in a part of the inside of the equipment, the volume change of the insulating oil is converted into the pressure change of the nitrogen gas, that is, the internal pressure change of the transformer, and the volume of the insulating oil is changed. Transformers that absorb change are known. In such a transformer, in order to diagnose the presence or absence of abnormalities in the coil and the deterioration of the insulating oil, it is common practice to periodically collect and analyze the insulating oil inside the equipment. Conventionally, the oil extraction method is as described in Patent Document 1 below, in which an oil extraction port provided at the bottom of a transformer is opened and insulating oil flowing out via a rubber tube attached to the oil extraction port is discharged into a can or a bottle. The method of extracting oil into a container such as is used.

JP-A-48-28295

However, in the above-mentioned transformer, depending on the environmental condition of the transformer, the internal pressure of the transformer may be in a negative pressure state lower than the external pressure (atmospheric pressure) of the transformer. In such a negative pressure state, if oil is extracted using the conventional oil extraction method described above, the transformer may suck the outside air and the air may be mixed into the inside of the device.

An object of the present invention is to solve such a problem, and an object of the present invention is to provide an oil extraction device capable of extracting insulating oil while preventing air from entering the inside of an apparatus.

According to one feature of the present disclosure, the oil extraction device extracts the insulating oil of the electric power equipment in which the inside of the equipment is filled with the insulating oil and the inside of the equipment is filled with the first inert gas. Further, the oil extraction device is provided with a recovery container for storing the collected insulating oil through the storage channel, and in the state before the insulating oil is extracted, the inside of the storage path and the container of the recovery container is a second inert gas. It is in a vacuumed state after being filled with.

Therefore, the air inside the container can be discharged by filling with the second inert gas. Therefore, it is possible to prevent the air inside the container from being mixed into the inside of the device. In addition, the internal pressure of the recovery device can be reduced by evacuation. Therefore, the insulating oil can be extracted by sucking the insulating oil inside the device inside the container.

According to another feature of the present disclosure, the oil extraction device includes a pressure gauge capable of measuring the internal pressure of the recovery container.

Therefore, the internal pressure of the recovery container can be confirmed. In addition, the pressure of the first inert gas of the electric power device can be compared with a pressure gauge capable of measuring the pressure. Therefore, it can be confirmed whether the internal pressure of the recovery container is higher or lower than the pressure of the first inert gas of the electric power device.

Further, according to another feature of the present disclosure, the inside of the collection container is evacuated by an electric vacuum pump.

Therefore, for example, it is possible to eliminate variations in the degree of evacuation inside the container as compared with the case where the vacuum pump is manually operated.

Further, according to another feature of the present disclosure, an oil extraction container for storing insulating oil is provided inside the container of the collection container.

Therefore, for example, a temporary storage container used for temporary storage of insulating oil can be used as an oil extraction container. Then, after the insulating oil is extracted, it is possible to eliminate the trouble of transferring the insulating oil for temporary storage.

Further, according to another feature of the present disclosure, the collection container is a hollow sphere having a uniform thickness formed by assembling two bowl-shaped hemispheres so as to overlap the peripheral edges of the respective openings.

Therefore, for example, when the recovery container is not spherical or the thickness is not uniform, a portion having low strength against pressure is generated. Therefore, it may not be able to withstand the negative pressure generated by the vacuum pump. On the other hand, since the recovery container is a sphere having a uniform thickness, a portion having low strength against pressure does not occur. Therefore, it can withstand the negative pressure generated by the vacuum pump.

It is the schematic which shows the state which the oil extraction device which concerns on embodiment is connected to a transformer. It is a figure which shows the system configuration of the oil extraction apparatus of FIG. It is a figure which shows the structure of the recovery device of FIG. FIG. 3 is a diagram showing a state in which the screwed member is screwed into the mounting member. It is a figure explaining the procedure which starts the oil extraction from the state of FIG. 2 (closes a negative pressure release valve). It is a figure explaining the next procedure of FIG. 5 (start filling with 2nd nitrogen gas). It is a figure explaining the next procedure of FIG. 6 (filling is finished, and a ball of an indicator floats up). It is a figure explaining the next procedure of FIG. 7 (close a gas filling valve and a degassing confirmation valve). It is a figure explaining the next procedure of FIG. 8 (the second nitrogen gas is discharged to the outside by operating a vacuum pump). It is a figure explaining the next procedure of FIG. 9 (check the pressure gauge, confirm that the pressure of the recovery vessel has fallen below the negative pressure of the transformer, stop the vacuum pump, and at the same time, the second nitrogen. Gas discharge is also completed). It is a figure explaining the next procedure of FIG. 10 (the transformer valve is opened and the insulating oil is started to be extracted. If the amount of the insulating oil is extracted at this time is small, the negative pressure of the recovery container is insufficient. Therefore, check the pressure gauge and operate the vacuum pump). It is a figure explaining the next procedure of FIG. 11 (the transformer valve is closed when oil extraction is completed).

Hereinafter, embodiments for carrying out the present invention will be described with reference to FIGS. 1 to 12. In the present invention, the insulating oil 4 filled in the transformer 1 is extracted by using the oil extraction device 10. Hereinafter, the transformer 1 and the oil extraction device 10 will be described individually.

First, the transformer 1 will be described (see FIG. 1). The transformer 1 includes a tank 2, a coil 3 housed in the tank inside 2a of the tank 2, an insulating oil 4 filled in the tank inside 2a, a first nitrogen gas 5 sealed in the tank inside 2a, and a first. 1 Consists of a first pressure gauge 6 attached to the upper part of the tank 2 so that the pressure of the nitrogen gas 5 can be measured, and a transformer valve 7 attached to the lower part of the tank 2 so that the insulating oil 4 inside the tank 2a can be discharged. Has been done. The first nitrogen gas 5 is, for example, a nitrogen gas having a nitrogen purity of 97% or more, and corresponds to the “first inert gas” described in the claims.

Next, the oil extraction device 10 will be described (see FIGS. 1 to 4). The oil extraction device 10 is composed of a flange 20 that can be attached to the transformer valve 7 and a recovery device 30 that is connected to the flange 20 and can store the insulating oil 4.

The flange 20 is composed of an oil extraction port 21 attached to the outlet 7a of the transformer valve 7, a check valve 22 for preventing backflow from the recovery device 30, and a gas filling valve 23. At this time, the oil extraction port 21 is connected to the inlet 22a of the check valve 22 and the outlet 23b of the gas filling valve 23 via the first connection portion 24 (see FIG. 2). The gas filling valve 23 is open to the atmosphere so that its inlet 23a is connected to an external nitrogen gas can 70. The second nitrogen gas 71 can be sealed in the oil extraction device 10 by using the nitrogen gas can 70. The second nitrogen gas 71 is, for example, a nitrogen gas having a nitrogen purity of 95% or more, and corresponds to the “second inert gas” described in the claims. The flange 20 is configured in this way.

The recovery device 30 includes a recovery container 31 which is a hollow sphere, a lid 32 attached to the recovery container 31, a hose 33 extending from the outlet 22b of the check valve 22 to the inside 31a of the recovery container 31, and oil-collected insulation. An oil sampling container 34 for storing the oil 4, a vacuum pump 35 capable of discharging the gas inside the container 31a to the outside, a first spacer 36 for providing the oil sampling container 34 inside the container 31a, and a vacuum pump 35 inside the container 31a. The second spacer 37 for providing the container, the second pressure gauge 38 capable of measuring the internal pressure of the recovery container 31, the negative pressure release valve 39, the degassing confirmation valve 40, and the filling of the second nitrogen gas 71 are detected. It is composed of a possible indicator 41 and a case 42 into which the collection container 31 can be fitted (see FIGS. 2 to 4). The first outlet 31b of the recovery container 31 is connected to the second pressure gauge 38, the inlet 39a of the negative pressure opening valve 39, and the inlet 40a of the degassing confirmation valve 40 via the second connecting portion 26 ( (See FIG. 2). At this time, the oil sampling port 21 to the outlet 33a of the hose 33 is a flow path 25 through which the insulating oil 4 is stored, and corresponds to the “storage path” described in the claims. Further, the second pressure gauge 38 corresponds to the "pressure gauge" described in the claims.

The collection container 31 is configured by assembling two bowl-shaped hemispheres, an upper hemisphere 50 and a lower hemisphere 51 (see FIG. 3). The upper hemisphere 50 and the lower hemisphere 51 are integrally molded products made of a rigid synthetic resin material such as acrylic resin, and have a thickness of, for example, several mm so as to withstand the negative pressure generated by the vacuum pump 35. In addition, the thickness is made uniform so that it can withstand more negative pressure by injection molding. Further, the upper hemisphere 50 and the lower hemisphere 51 are provided with flanges 52 and 53 on the peripheral edge of the opening, and the flanges 52 and 53 are formed with eight through holes 54 and 55 at equal angular intervals. There is. A mounting hole 59 to which the lid 32 can be mounted is formed on the spherical surface of the upper hemisphere 50. When assembling the upper hemisphere 50 and the lower hemisphere 51, the flanges 52 and 53 are vertically overlapped with each other, and the flanges 52 and 53 are assembled using a plurality of screws 56 and nuts 57 through the through holes 54 and 55. At this time, the gas sealer 58, which is a ring-shaped one-component RTV rubber, is sandwiched between the flanges 52 and 53, so that the gas sealer 58 closes the gap between the flanges 52 and 53, and the outside air is released. It is possible to prevent the mixture from being mixed into the inside 31a of the container.

The lid 32 is composed of a mounting member 60 that is mounted in the mounting hole 59 and a screwing member 61 that is screwed into the mounting member 60. The mounting member 60 is a cylinder 62 having a flange 63 at one end, and is mounted by fitting the cylinder 62 into the mounting hole 59 so that the flange 63 faces up (see FIG. 3). A female screw is formed on the inner surface 62a of the cylinder 62. Further, the screwing member 61 is a cylinder 64 whose one end is closed by a disk 65. A screw is formed on the outer surface 64a of the cylinder 64 so as to be screwable with the inner surface 62a of the cylinder 62. When screwing the screwing member 61 into the mounting member 60, the other end of the screwing member 61 is brought closer from above the mounting member 60 mounted in the mounting hole 59, so that the inner surface 62a of the mounting member 60 and the outer surface 64a of the screwing member 61 , Are screwed together (see FIG. 3). Then, the flange 63 and the disk 65 are locked so as to overlap each other (see FIG. 4). At this time, a through hole 66 is formed in the center of the disk 65 so as to communicate the outside and the internal space of the cylinder 64. Therefore, the hose 33 described above can extend from the outside to the inside of the container 31a through the through hole 66 even when the screwing member 61 is screwed into the mounting member 60.

The oil extraction container 34 is provided inside the container 31a so that the oil extraction insulating oil 4 can be stored, and is shaped like a bottle, for example. Further, the oil extraction container 34 is, for example, a temporary storage container used when temporarily storing the insulating oil 4. The volume of the oil extraction container 34 is set to exceed, for example, 500 ml required for temporary storage of the insulating oil 4.

The vacuum pump 35 is provided inside the container 31a and is capable of discharging gas from the intake port 35a toward the exhaust port 35b. The intake port 35a is connected to the inside 31a of the container, and the exhaust port 35b is connected to the second outlet 31c of the collection container 31 via the third connection portion 43 (see FIG. 2). The second outlet 31c of the collection container 31 is connected to the outside and is open to the atmosphere. A check valve 44 is provided in the third connection portion 43 so that external air does not flow back into the container inside 31a.

The first spacer 36 is a disk having an outer diameter smaller than the diameter of the collection container 31, and is provided at a lower portion in the vertical direction in the container inner 31a (see FIGS. 3 to 4). The oil extraction container 34 is installed on the first spacer 36 when it is provided inside the container 31a.

The second spacer 37 is a ring-shaped disk having an outer diameter substantially the same as the diameter of the collection container 31 and having a through hole 37a in the center, and is provided at a central portion in the vertical direction inside the container 31a (see FIG. 3). ). The vacuum pump 35 is installed on the second spacer 37 when it is installed inside the container 31a. Further, the oil extraction container 34 penetrates the through hole 37a when it is provided inside the container 31a. Therefore, the oil extraction container 34 is configured such that the central portion is supported by the second spacer 37 to prevent tilting and tipping (see FIGS. 3 to 4).

The outlet 39b of the negative pressure release valve 39 is connected to the outside and is open to the atmosphere. The outlet 40b of the degassing confirmation valve 40 is connected to the inlet 41a of the indicator 41 via the fourth connecting portion 45. The outlet 41b of the indicator 41 is connected to the outside and is open to the atmosphere. Further, the indicator 41 includes a ball 67 that is levitated by the second nitrogen gas 71. Therefore, the indicator 41 can detect the encapsulation of the second nitrogen gas 71 by the ball 67.

The case 42 is a molded product made of a rigid synthetic resin material such as a hard low-foaming vinyl chloride resin, and is provided with a curved notch 68 into which about a quarter of the collection container 31 can be fitted. The case 42 can be assembled with the collection container 31 by tightening the upper surface 69 of the case 42 together with a part of a plurality of screws 56 for assembling the collection container 31 with the collection container 31 fitted in the notch 68. (See FIGS. 3-4). Further, the case 42 can integrally accommodate the second pressure gauge 38, the negative pressure release valve 39, the degassing confirmation valve 40, and the indicator 41. The recovery device 30 is configured in this way.

Subsequently, a method of collecting the insulating oil 4 filled in the tank inside 2a of the transformer 1 will be described. This oil extraction method is a procedure when the pressure of the first nitrogen gas 5 of the transformer 1 exceeds the external pressure (atmospheric pressure) of the tank 2 and the pressure of the first nitrogen gas 5 of the transformer 1 is the external pressure of the tank 2. There are procedures and procedures for cases below (atmospheric pressure). Therefore, first, using the first pressure gauge 6 of the transformer 1, it is confirmed whether the pressure of the first nitrogen gas 5 of the transformer 1 exceeds or falls below the external pressure (atmospheric pressure) of the tank 2. There is a need. This is the case where the pressure of the first nitrogen gas 5 exceeds or falls below the external pressure (atmospheric pressure) of the tank 2 due to the volume change of the insulating oil 4 caused by the temperature change of the tank 2 due to seasonal changes or the like. Because there is. The procedure in each case will be described below.

First, a case where the pressure of the first nitrogen gas 5 exceeds the external pressure (atmospheric pressure) of the tank 2 will be described. At this time, even if the inside 2a of the tank and the outside are directly connected, the outside air is not sucked into the inside 2a of the tank. Therefore, by opening the transformer valve 7 in a state where the outlet 7a of the transformer valve 7 is connected to the outside and is open to the atmosphere, the insulating oil 4 can be extracted without air being mixed into the tank inside 2a. In addition, reliable oil extraction is possible by using a clamp or the like for the oil extraction device 10 instead of a rubber stopper or the like.

Next, a case where the pressure of the first nitrogen gas 5 is lower than the external pressure (atmospheric pressure) of the tank 2 will be described. At this time, if the inside 2a of the tank and the outside are directly connected, the outside air is sucked into the inside 2a of the tank. Therefore, the insulating oil 4 filled in the tank inside 2a is extracted by using the oil extraction device 10 described above. The procedure for extracting the insulating oil 4 using the oil extraction device 10 will be described below (see FIGS. 2 to 12).

First, the work of closing the negative pressure release valve 39 is performed from the state shown in FIG. 2, that is, the state in which the oil extraction port 21 of the flange 20 is attached to the outlet 7a of the transformer valve 7 in the closed state (see FIG. 5). ..

Next, a nitrogen gas can 70 is connected to the inlet 23a of the gas filling valve 23, and the oil extraction device 10 is filled with the second nitrogen gas 71 (see FIG. 6). Then, the second nitrogen gas 71 begins to be filled in the container interior 31a of the recovery container 31 through the gas filling valve 23 and the flow path 25. At this time, the air 80 originally existing in the container interior 31a of the recovery container 31 is discharged to the outside from the first outlet 31b of the recovery container 31 through the degassing confirmation valve 40 and the indicator 41.

Further, the second nitrogen gas 71 is completely filled in the container inner 31a of the recovery container 31, and then is also filled in the indicator 41 from the first outlet 31b of the recovery container 31 through the degassing confirmation valve 40. To. When the second nitrogen gas 71 is completely filled in the indicator 41, the balls 67 are levitated by the second nitrogen gas 71 (see FIG. 7). As described above, the oil extraction device 10 is configured so that the indicator 41 can detect that the inside 31a of the recovery container 31 is completely filled with the second nitrogen gas 71.

Next, the filling of the second nitrogen gas 71 is stopped, and the gas filling valve 23 and the degassing confirmation valve 40 are closed (see FIG. 8). As a result, the oil extraction device 10 has a configuration that can prevent air from entering from the outside.

Then, the vacuum pump 35 is operated to discharge the second nitrogen gas 71 filled in the container interior 31a of the recovery container 31 to the outside. (See FIG. 9). Then, the internal pressure of the recovery container 31 decreases, and a negative pressure is generated in the container internal 31a. At this time, a negative pressure of about -60 kPa is generated in the container internal 31a with respect to the atmospheric pressure (= about 100 kPa) by the vacuum pump 35. The first nitrogen gas 5 generates a negative pressure of about −40 kPa with respect to the atmospheric pressure (= about 100 kPa) in the state where the pressure is the lowest. Therefore, the vacuum pump 35 can make the internal pressure of the recovery container 31 lower than the pressure of the first nitrogen gas 5. Comparing the first pressure gauge 6 and the second pressure gauge 38, when the internal pressure of the recovery container 31 becomes lower than the pressure of the first nitrogen gas 5, the vacuum pump 35 is stopped (FIG. 10). reference).

Next, the work of opening the transformer valve 7 is performed (see FIG. 11). Then, the insulating oil 4 in the tank inside 2a is sucked into the container inside 31a having a lower pressure, flows through the flow path 25, and is stored in the oil extraction container 34 of the recovery container 31. Finally, when the required amount of insulating oil 4 is stored, the work of closing the transformer valve 7 is performed (see FIG. 12). In this way, the insulating oil 4 filled in the tank inside 2a can be extracted by using the oil extraction device 10.

The oil extraction device 10 according to the embodiment of the present invention is configured as described above. According to this configuration, the oil extraction device 10 extracts the insulating oil 4 of the transformer 1 in which the inside 2a of the tank is filled with the insulating oil 4 and is sealed with the first nitrogen gas 5. Further, the oil extraction device 10 includes a recovery container 31 for storing the collected insulating oil 4 via the flow path 25, and in a state before the insulating oil 4 is extracted, the inside of the flow path 25 and the recovery container 31 is inside the container. 31a is in a state of being vacuumed after being filled with the second nitrogen gas 71. Therefore, the air 80 inside the container 31a can be discharged by being filled with the second nitrogen gas 71. Therefore, it is possible to prevent the air 80 inside the container 31a from being mixed into the inside 2a of the tank. Further, the internal pressure of the recovery device 30 can be lowered by evacuation. Therefore, the insulating oil 4 can be extracted by the inside 31a of the container sucking the insulating oil 4 inside the tank 2a.

Further, according to this configuration, a second pressure gauge 38 capable of measuring the internal pressure of the recovery container 31 is provided. Therefore, the internal pressure of the recovery container 31 can be confirmed. It can also be compared with the first pressure gauge 6 of the transformer 1. Therefore, it can be confirmed whether the internal pressure of the recovery container 31 is higher or lower than the pressure of the first nitrogen gas 5 of the transformer 1.

Further, according to this configuration, the inside 31a of the collection container 31 is evacuated by the electric vacuum pump 35. Therefore, for example, it is possible to eliminate variations in the degree of vacuuming inside the container 31a as compared with the case where the vacuum pump 35 is manually operated.

Further, according to this configuration, the inside 31a of the recovery container 31 is provided with an oil collection container 34 for storing the insulating oil 4. Therefore, for example, a temporary storage container used for temporary storage of the insulating oil 4 can be used as the oil extraction container 34. Then, after the insulating oil 4 is extracted, it is possible to eliminate the trouble of transferring the insulating oil 4 for temporary storage.

Further, according to this configuration, the collection container 31 is assembled so that the upper hemisphere 50 and the lower hemisphere 51, which are two bowl-shaped hemispheres, overlap the flanges 52 and 53 on the peripheral edges of the respective openings. It is a hollow sphere of uniform thickness formed by being formed. Therefore, for example, when the recovery container 31 is not spherical or has a non-uniform thickness, a portion having low strength against pressure is generated. Therefore, it may not be able to withstand the negative pressure generated by the vacuum pump 35. On the other hand, since the recovery container 31 is a sphere having a uniform thickness, a portion having low strength against pressure does not occur. Therefore, it can withstand the negative pressure generated by the vacuum pump 35. When the inside 31a of the recovery container 31 is evacuated, the external pressure is evenly applied to the surface of the recovery container 31. Therefore, the recovery container 31 can withstand the negative pressure generated by the vacuum pump 35.

The above-mentioned contents are merely related to one embodiment of the present invention, and do not mean that the present invention is limited to the above-mentioned contents.

In this embodiment, "transformer 1" has been described as an example of "electric power equipment". However, the present invention is not limited to this, and a "silicon rectifier", a "series reactor", or the like may be used. Moreover, "the first nitrogen gas 5" was described as an example of the "first inert gas". However, the present invention is not limited to this, and may be "argon" or the like. Moreover, "second nitrogen gas 71" was described as an example of "the second inert gas". However, the present invention is not limited to this, and may be "argon" or the like. Further, the "first inert gas" and the "second inert gas" have been described as different gases. However, the present invention is not limited to this, and may be the same.

1 Transformer (electric power equipment)
2a Inside the tank (inside the equipment)
4 Insulation oil 5 1st nitrogen gas (1st inert gas)
10 Oil extraction device 25 Channel (storage channel)
31 Recovery container 31a Inside the container 34 Oil extraction container 35 Vacuum pump 38 Second pressure gauge (pressure gauge)
50 Upper hemisphere 51 Lower hemisphere 71 Second nitrogen gas (second inert gas)

Claims (5)

It is an oil extraction device that extracts the insulating oil of electric power equipment that is filled with insulating oil and is filled with the first inert gas.
It is equipped with a recovery container that stores the extracted insulating oil via a storage channel.
An oil extraction device in which the inside of the storage channel and the recovery container is evacuated after being filled with the second inert gas before the insulating oil is extracted. The oil extraction device according to claim 1.
An oil extraction device equipped with a pressure gauge that can measure the internal pressure of the recovery container. The oil extraction device according to any one of claims 1 and 2.
The inside of the collection container is an oil extraction device that is evacuated by an electric vacuum pump. The oil extraction device according to any one of claims 1 to 3.
An oil extraction device equipped with an oil extraction container for storing insulating oil inside the collection container. The oil extraction device according to any one of claims 1 to 4.
The collection container is an oil extraction device that is a hollow sphere of uniform thickness formed by assembling two bowl-shaped hemispheres so as to overlap the peripheral edges of the respective openings.

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