JPS6343961B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an insulating gas container for electrical equipment that insulates a high potential part with an insulating gas.
In particular, the present invention relates to an insulating gas container that allows easy filling and recovery of an insulating gas such as SF ₆ , which has a relatively low filling pressure.

Conventionally, a typical example of electrical equipment using insulating gas is a gas-insulated switchgear that uses SF ₆ gas as an insulating medium, but the pressure of SF ₆ gas sealed is 1 kg/cm ² g (= 2.0 × 10 ⁵ Pa) In most low gas pressure devices, a rectangular parallelepiped is used as the insulating gas container. Such a rectangular container is more easily deformed than a round or cylindrical container, and in order to fill the container with gas by vacuuming, the wall thickness of the container must be increased.
There was also the problem that it was too heavy. Additionally, when recovering SF ₆ gas from a container during inspections, etc., it is easy to recover the gas pressure above atmospheric pressure, but the gas below atmospheric pressure must be recovered using a vacuum pump. Due to the long time required, there was a drawback that not all the SF ₆ gas in the container could be recovered.

In view of the above, it is an object of the present invention to provide an insulating gas container that can easily fill the cylinder with liquefied insulating gas under normal pressurization, and can efficiently perform recovery operations.

Moreover, the object of this invention is to solve the conventional square shape,
Another object of the present invention is to provide an insulating gas container that does not have a large wall thickness and allows easy filling and collection of insulating gas.

A further object of the present invention is to provide an insulating gas container that can rationally fill and recover insulating gas by effectively utilizing the density difference between the insulating gas and the surrounding air.

Next, various experiments conducted by the inventor before completing this invention will be explained.

Figure 1 of the attached drawing shows a rectangular container V with a volume of ^1.5m3 .
SF ₆ gas at points A and B inside the container when SF ₆ gas is injected from the top and residual gas is exhausted from the bottom.
It shows the temporal change in gas concentration,
Both points A and B are the same curve. The SF ₆ gas injection rate in this case is 70/min.

Figure 2 shows the change in SF ₆ gas concentration at points A and B when SF ₆ gas is injected from the side of the container V and residual gas is exhausted from the bottom under the same conditions as in Figure 1. be.

FIG. 3 shows the change in SF ₆ gas concentration at point A when SF ₆ gas is injected from the bottom and residual gas is discharged from the top under similar conditions.

Based on the above facts, as shown in Figure 3, SF ₆ gas is injected from the bottom of the container and residual gas (air) is removed.
It was found that the method of discharging from the top is effective.

Next, Figure 4 shows the inside A of the container when openings with the same cross-sectional area at the top and bottom of the container V of the same shape and size are already filled with SF ₆ gas.
Figure 2 shows the change in _SF6 gas concentration at a point. These results showed that SF ₆ gas's own weight easily caused it to be replaced with the atmosphere.

This invention was made based on the above experimental results, and to explain one embodiment shown in FIGS. 5 and 6, SF ₆ gas is injected into and discharged from the bottom wall 1A of a rectangular container 1. A first passage hole 2 for air discharge and a second passage hole 3 for air to be discharged and inflowed are provided, and a conduit 4 whose upper end opening 4A is located at the upper part of the container 1 is connected to the passage hole 3. A cover body 6 to which a pipe 5 is connected is attached to the passage hole 2. 7 is a stop valve. A lid 8 is attached to the second passage hole 3.

To explain the operation of the insulating gas container with the above configuration, SF ₆ gas is injected, and the new SF ₆ gas, which is filled in the cylinder in a liquefied state, is heated at 20℃.
21.85 atm・abs (=2.2×10 ⁶ Pa) at 0℃
13.04atm・abs (=1.32×10 ⁶ Pa). When the valve of the SF ₆ gas cylinder is opened and then the stop valve 7 is opened to an appropriate opening degree, SF ₆ gas is injected into the container 1 . At this time, the passage hole 3 is left open. Then
SF ₆ gas pushes up the air inside the container, which has a low density,
This air is discharged through the passage hole 3 through the conduit 4 in the same manner as shown in FIG. When the SF ₆ gas almost completely occupies the inside of the container 1, _{the discharge of SF 6 gas} from the passage hole 3 increases rapidly. The hole 3 may be closed with the lid 8.

Next, for equipment inspection etc., SF ₆ gas is poured into container 1.
Since it is necessary to recover the SF ₆ gas when discharging the gas from the SF 6 gas, when the lid 8 is first opened and then the lid 6 is opened, the SF ₆ gas flows out from the first passage hole 2 due to its own weight. Correspondingly, air flows in through the second passage hole 3 and is displaced into the container 1 through the conduit 4. In this way, the SF ₆ gas that flows out can be recovered and reused. At this time, the outflow speed of SF ₆ gas decreases as the amount of air flowing in increases, so it is difficult to recover 100% of SF ₆ gas, but most of it can be recovered.

FIG. 7 shows another embodiment of the present invention, in which a first passage hole 2 and a second passage hole 3 to which a conduit 4 is connected are provided adjacent to each other in the side wall 1B of the container 1. Thus, the same functions and effects as those achieved by the configuration shown in FIG. 5 can be realized.

As described above, according to the present invention, the insulating gas can be easily filled and recovered without reducing the purity of the filled insulating gas. In addition, since the inlet and exhaust port are located close together at the bottom of the container,
It has the advantage of being able to avoid work at heights, and preventing rain from entering the container when installed outdoors.

[Brief explanation of the drawing]

Figures 1 to 4 show SF ₆ gases tested for various injection and discharge modes into the container, respectively _.
FIG. 5 is a schematic diagram of the structure of one embodiment of the present invention, FIG. 6 is a sectional view of the main part, and FIG. 7 is a schematic diagram of the structure of another embodiment. 1: Container, 2: First passage hole, 3: Second passage hole, 4: Conduit, 6, 8: Lid, 7: Stop valve.

Claims (1)

[Scope of Claims] 1. In the insulating gas container of an electrical device in which a high potential part is insulated using an insulating gas, a first passage hole that can be opened and closed through which the insulating gas flows in and is discharged, and a first passage hole through which the surrounding air is discharged. , a second passage hole for inflow that can be opened and closed is provided in the lower part of a rectangular parallelepiped container in close proximity to each other, and a conduit whose upper end opens into the upper part of the container is connected to the second passage hole. An insulating gas container for electrical equipment featuring: 2. The insulating gas container for electrical equipment according to claim 1, wherein the first and second passage holes are provided in the bottom wall of the container. 3. The insulating gas container for electrical equipment according to claim 1, wherein the first and second passage holes are provided at a lower side wall of the container.