JPS60160310A - Gas insulated cubicle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a gas insulated cubicle configured by housing a plurality of electrical devices in a closed container filled with 8F6 gas.

[Technical background of the invention and its problems]

Recently, power receiving and transforming equipment for electric power and general industry has been developed.6 6/
For 77 kV class cubicles, there is a tendency to use gas insulated cubicles using 8F6 gas, which has excellent insulation properties, with the aim of reducing space factors, reducing costs, and streamlining.

Now, an example of a conventional gas insulated cubicle is shown in a side view of the structure and arrangement in FIG. , is led out to the bus 10 by the bus 3 via the lightning arrester 4, the voltage transformer 5, the disconnector 6, the grounding device 7, the breaker 8, the current transformer 9, etc.

The metal hermetic container 1 has an opening 11 that serves as an entry port for equipment, but after the equipment is stored in the container, the metal hermetic container 1 is opened with a lid 13 via a gasket 12 to maintain airtightness inside the metal hermetic container 1. Dejiya is closed. After that, SF is placed inside the metal ring sealed container 1.
, gas is injected.

In this way, a gas-insulated cubicle is a combination of many devices housed in a metal hermetically sealed container, so in order to increase the insulation between adjacent devices, S is installed in the space inside the container.
F. Pressurized gas.

Therefore, since internal pressure acts on the metal hermetic container 1, a pressure container is usually used. As a result, thick-walled containers are used, which has the disadvantage of being heavy. However, recently, improvements in gas insulation technology have made it possible to use gas-insulated cubicles that lower the gas pressure inside the sealed container.In this case, there is no need to use a pressure vessel, and a box with a lightweight thin plate structure can be used instead. It is now possible to configure containers with .

On the other hand, in the event that the 8F gas enclosed in these gas-insulated cubicles were to leak, an arc accident such as a short circuit would occur due to the short insulation distance between each device, and the equipment would be damaged. Dangerous situations such as destruction or explosion inside the container may occur. Therefore, the container used in the gas insulated cubicle must have a structure that is sufficiently airtight to prevent gas leakage.

However, there is a concern that gas leakage may occur in the metal hermetic container 1 described above during long-term use, and efforts are being made to take countermeasures against this problem. FIG. 2 is a sectional view showing a seal portion for sealing the opening 11. The lid 13 is attached to the metal hermetic container 1 via a flange 15, and the flange 15 has a gasket groove 15a. The structure is such that airtightness is maintained by inserting the gasket 12 into this and tightening the lid 13 with bolts 16. In such a sealed structure, the gap around the seal is filled by the 120-round shell to maintain airtightness. However, the packing 12 is generally made of rubber or synthetic resin.
A material such as IJ is used, and when used for a long period of time, it is inevitable that the elastic force will decrease due to deterioration of the material over time. In addition, such materials may be subject to accelerated deterioration due to thermal or chemical interference, and furthermore, the airtightness of mechanical contact surfaces may cause leaks due to insufficient tightening force, for example. be.

Therefore, in order to improve the compatibility of a gas insulated cubicle, the length of the seal by such a packing should be as short as possible, and if possible, a completely integrated structure such as a welded structure should be used. was desired.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and has a highly reliable welded structure as a sealing structure for the mouth part of a metal sealed container, so that it is highly reliable and does not deteriorate in airtightness even after long-term use. The object of the present invention is to provide a gas-insulated cubicle that is also lightweight.

[Summary of the invention]

The present invention uses a welded structure as a whole to seal the container after transporting and assembling the internal equipment inside the metal hermetic container of the gas insulated cubicle, thereby eliminating the aging factor and creating a semi-permanently airtight seal. By using laser welding, which generates little welding distortion and welding heat, we have created a metal sealed container with a thinner plate and lighter weight, which is highly reliable and lightweight. The company provides gas insulated cubicles.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4.

As shown in FIG. 3, electrical equipment to be installed in the metal hermetic container 1 is carried in through an opening 11 provided on the side surface of a metal hermetic container l made of a thin copper plate, and then the opening 11 is sealed. Conventionally, sealing was performed with a packing instead of this hermetic seal. In this embodiment, this is a welded structure that is highly reliable in terms of its ability to maintain airtightness, and this is made possible by using laser welding, which has excellent weldability for thin plates.

That is, as shown in detail in FIG. 3, the edge 1 of the opening 11
A flange 17 is joined to 1a. Fillet welding 11b and IIC can be performed on this part from both sides, and even if an opening is to be opened later for repair, this part will not be disassembled, so it is possible to join using a general welding method, such as arc welding. You may. Next, a wire 18 made of a thin copper plate is placed on the flange 17, and a laser beam 20 excited from a laser oscillator 19 is irradiated onto the electrical connection portion with the flange 17.

As a result, the portion 18a irradiated with the laser beam is bath melted, and so-called 1-stroke welding by laser welding is performed.

As mentioned above, recent advances in insulation technology have made it possible to fabricate non-pressure vessels, and in situations where the box body is made of thin plates, conventional welding methods such as arc welding have a large welding heat input, so thin plates can be fabricated. lap welding is a national problem. Therefore, skilled skills and careful attention are required.
In other words, it may cause a decrease in reliability. The most worrisome drawback in this case is that the degree of difficulty in welding decreases the reliability of airtightness, which is most important for gas insulated cubicles. However, in the embodiment of the present invention, highly reliable welding is achieved by using laser lap welding, which is a welding method suitable for joining thin plates.

First of all, [in contrast to the sealing structure, which has the risk of changing the material and deteriorating the airtight performance, the sealing by bath welding has a permanent airtightness, and in this point, it requires no maintenance. do not have. Similarly, although parts such as instruments and cable entrances and exits remain as a packing structure according to the present invention,
The total extension distance of such a packing is significantly reduced compared to the conventional structure. In this case, the airtight reliability of the container of the present invention is significantly improved since it is approximately proportional to the total seal length.

Furthermore, since the present invention does not use a packing [2] like the conventional gas insulated cubicle shown in FIGS. 1 and 2, there is no need to provide the packing groove Since considerable precision is required, this process eliminates the need for mechanical finishing of the surrounding flanges 15 and m13, significantly shortening machining time and improving productivity. In addition, the 72-inch structure with the packing groove requires rigidity so as not to deform during tightening, so the N cover is also very large. In addition, as shown in Figure 2, the conventional wear 13 requires a certain amount of thickness to prevent airtight leaks due to deformation of the delivery part, and has two layers of thickness. It was processed such as. However, in this embodiment, as shown in FIG. 4, 418 may be a simple single plate, and it is sufficient to gas cut or laser cut the plow board. Therefore, it is possible to significantly shorten the machining time and reduce the weight of the peripheral portion of the flange.

According to the present invention, deformation of the companion body due to welding distortion can be prevented. A box with a thin plate structure is easily deformed due to welding distortion, and is usually used after being corrected to remove the distortion. However, after various electrical components have been installed and adjusted in the gas-insulated cubicle and the final sealing process has been completed, such strain relief correction cannot be performed. This is a major drawback in terms of accuracy and appearance of the gas insulated cubicle. However, in the laser bath welding of the present invention, the occurrence of welding distortion can be suppressed to a very low level, so that highly accurate welding can be performed without the need for post-processing.

Since laser welding is performed by irradiating a laser beam with high density energy, the amount of heat input during welding is much smaller than that of other general welding methods. Therefore, in addition to the above-mentioned special ridges with small welding distortion, there are the following points when applied to box welding.

That is, the temperature rise during welding is small, and there is no lateral movement caused by heat to the internal electrical equipment.

In addition, it is not a scale that does not appear distorted in appearance, and it can form a clean bead with a small melt width, so it can be painted and made into a product without surface finishing.

Furthermore, and this is an important advantage, since the weld is formed by a thin linear bead, it is relatively easy to pull the weld when overlapping welding with a bead of, for example, @I In. It can be peeled off. That is, even if it becomes necessary to unseal the gas insulated cubicle for repair or other reasons, the lid 18 can be removed and the opening 11t opened for repair. Further, in this case, the flange 17 is thicker than the lid 18 and therefore is not damaged, so that it can be repaired with a new lid 18.

FIG. 5 shows another embodiment of the present invention, in which a closed gold bullion container 1 and a lid 1 are shown.
This uses an L-shaped flange 17a in which the flange located in the middle of the flange 8 has an L-shaped cross section. That is, the clamp vise 22 is used to prevent the lid 1B from warping and to ensure that the part 21 to be welded is in close contact with the lid 1B.
It was made so that it could be held down. By doing this, when laser welding the lid 18, there is no need to temporarily attach several parts to hold the lid 18 or use other fixing jigs, etc., and laser welding with good workability can be performed. can.

FIG. 6 shows another embodiment of the present invention, which uses a U-shaped flange 17b having a U-shaped cross section, and has the same effect as the embodiment shown in FIG.

〔Effect of the invention〕

According to the present invention, the airtight container of a gas insulated cubicle can be made extremely lightweight by using a thin steel plate, and the main parts are entirely welded to create a highly reliable gas insulated cubicle with guaranteed airtightness. Obtainable.

[Brief explanation of drawings]

1 is a schematic diagram of a conventional gas insulated cubicle, FIG. 2 is a partial sectional view of the opening shown in FIG. 1, FIG. 3 is a schematic diagram of a gas insulated cubicle according to an embodiment of the present invention, and FIG.
This figure is a partial sectional view of the opening shown in FIG. 3, and FIGS. 5 and 6 are partial sectional views showing other embodiments of the opening. 1...Metal sealed container 17, flange 18, lid (7317) Agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1 Figure 2 /7, 3 /6 /2 15α Figure 3 Figure 4 /

Claims (1)

[Claims] (1) In a gas-insulated cubicle in which electrical equipment is housed in an all-pole hermetically sealed container filled with insulating gas, the flange of the box opening and the outer plate that make up the metal hermetic container are irradiated with a laser beam and bonded to form a box. A gas-insulated cubicle characterized by having a canned structure over its entire body. (2. The gas insulated cubicle according to claim 1, characterized in that the flange of the box body has an L-shaped or U-shaped cross section.