JP5836205B2 - Gas insulated switchgear - Google Patents

Description

  The present invention relates to a gas insulated switchgear, and more particularly to a connection structure between tanks.

  The gas insulated switchgear is configured by housing various devices in a metal tank filled with an insulating gas and grounding the tank. Moreover, the tank is, for example, cylindrical, and a flange is formed at the end thereof. The tanks are connected by fastening the flanges together using a fastening member such as a bolt or a screw rod.

  By the way, when the flange surfaces are painted, the bolts or screw rods that fasten the flanges come into contact with the tank via the painted surfaces of the flange surfaces. As a result, the bolt or screw rod becomes a floating electrode, and the floating electrode becomes a source of induced voltage, which may cause a surge in the jacket.

  Therefore, conventionally, for example, a saw-like structure is provided on a nut that comes into contact with the flange, and the coating film is removed by the teeth to ensure electrical contact (see Patent Document 1). In addition, for example, a conductive member such as a ground plate is disposed between the flange and the nut, and a grounding structure is provided by using a bolt and a joint structure, thereby ensuring additional electrical contact (Patent Document) 2).

JP 2001-238314 A JP 2002-291124 A

  However, when applying the conventional technique described in Patent Document 1 or 2 to an existing gas-insulated switchgear to secure electrical contact, the bolts that have already been tightened are removed, reattached, and gas There was a concern that a large amount of work costs would be generated due to deterioration in work efficiency, such as the need for processing work. In addition, depending on the tightening structure, there is a possibility that the bolt may be rotated. In this case, there is a concern that it is necessary to perform the retightening operation by partially disassembling the gas insulated switchgear.

  The present invention has been made in view of the above, and in an existing gas insulated switchgear in which a tank is connected by fastening flanges whose surfaces are coated to each other with a fastening member including a bolt or a screw rod, the fastening member A gas-insulated switchgear that can easily secure electrical contact between the bolt or screw rod and the tank without removing the bolt, prevent the bolt or screw rod from becoming a floating electrode, and prevent the occurrence of jacket surge The purpose is to provide.

  In order to solve the above-described problems and achieve the object, in the gas insulated switchgear according to the present invention, a first flange is provided at one end in the axial direction, and at least on both sides in the axial direction of the first flange. A first tank having a ground potential whose surface is covered with a coating film, and a second flange facing the first flange are provided at one end in the same direction as the axial direction, and the entire surface of the second flange A second tank having a ground potential covered with a coating film, an insulating spacer sandwiched between the first and second flanges, a bolt penetrating the first and second flanges and the insulating spacer, or A fastening member including a screw rod and a fastening nut that is screwed into a tip portion of the bolt or screw rod protruding from the first flange and fastens the first and second flanges; The tip protruding from the base is penetrated and attached to the tip, and one end of the tip contacts the portion where the coating film on the side surface of the first flange is removed, and the bolt or screw rod is A metal fitting that maintains the same electric potential as the first tank, and a metal fitting fixing nut that is screwed into the tip portion protruding from the metal fitting and fixes the metal fitting to the tip portion.

  According to the present invention, electrical contact between the bolt or screw rod and the tank can be easily ensured without removing the fastening member, preventing the bolt or screw rod from becoming a floating electrode, and preventing the occurrence of a jacket surge. Has the effect of being able to.

FIG. 1 is a side view showing a configuration of a tank connection portion in a gas insulated switchgear according to an embodiment. FIG. 2 is a detailed view of part A in FIG. FIG. 3 is a detailed view of part A in a conventional gas insulated switchgear.

  Embodiments of a gas insulated switchgear according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment.
FIG. 1 is a side view showing a configuration of a tank connecting portion in the gas insulated switchgear according to the present embodiment. FIG. 2 is a detailed view of part A in FIG. Hereinafter, the configuration of the present embodiment will be described with reference to FIGS. 1 and 2.

  The tank 1 is, for example, a cylindrical metal container, and a flange 2 is provided at one end in the axial direction thereof. Similarly, the tank 7 is, for example, a cylindrical metal container, and is arranged so that the axial direction coincides with the tank 1, and a flange 8 is provided at one end of the flange 2 side. The tanks 1 and 7 have insulating spacers 3 (insulating members) interposed between the flanges 2 and 8, and the flanges 2 and 8 are fastening members (fastening bolts 4, fastening washers 6a and 6b, and fastening nuts 5) described later. They are connected to each other by fastening. The tanks 1 and 7 are filled with insulating gas. The tanks 1 and 7 are grounded.

  The surface of the flange 2 is covered with an insulating coating film (not shown) except for a part thereof. Specifically, at least the surfaces on both sides in the axial direction of the flange 2 are covered with a coating film. That is, both the surface of the flange 2 on the tank 7 side and the surface of the flange 2 opposite to the tank 7 side are covered with the coating film. Although the side surface (circumferential surface) of the flange 2 is generally covered with a coating film, the coating film is previously removed from a predetermined region including a contact portion of the grounding conductive metal fitting 9 described later. For example, the surface of the flange 8 is entirely covered with an insulating coating film (not shown).

  The flanges 2 and 8 are fastened to each other by fastening members including fastening bolts 4 with the insulating spacer 3 interposed therebetween. That is, the flanges 2 and 8 and the insulating spacer 3 are provided with flange fastening holes (not shown) penetrating them in the axial direction, and the fastening bolts 4 are inserted through the holes. The head of the fastening bolt 4 is disposed on the tank 7 side, for example, and a fastening washer 6 b is disposed between the head and the flange 8. On the other hand, the front end 4 a of the fastening bolt 4 penetrates the flange 2 and protrudes. Further, the tip 4a is threaded. A fastening nut 5 is screwed to the distal end portion 4a via a fastening washer 6a disposed on the surface of the flange 2, and the flanges 2 and 8 are fastened with the insulating spacer 3 interposed therebetween. Note that the fastening structure using the fastening bolt 4, the fastening washers 6a and 6b, and the fastening nut 5 is the same as that of the prior art, and is provided in an existing gas insulated switchgear. FIG. 3 shows a detailed configuration of part A in a conventional gas insulated switchgear. 3, the same components as those in FIG. 2 are denoted by the same reference numerals.

  In the present embodiment, a grounding metal fitting 9 is further attached to the distal end portion 4a, and this is fixed with a metal fitting fixing nut 10. Specifically, after attaching the grounding conductive metal fitting 9 to the front end 4a by passing the front end 4a through a hole (not shown) provided in the grounding conductive metal fitting 9, it is fastened to the front end 4a. The nut 5 is screwed and the grounding conductive metal fitting 9 is fastened with the metal fitting fixing nut 10 to be fixed to the tip end portion 4a. 2 can be provided for each fastening bolt 4 (see FIG. 1).

  The grounding metal fitting 9 is formed by, for example, bending a flat metal member into a substantially L shape, and its tip is in contact with the side surface (circumferential surface) of the flange 2 and is electrically connected. Here, on the side surface (circumferential surface) of the flange 2, the coating film is previously removed from a predetermined region including a contact portion of the grounding conductive metal fitting 9. That is, in the existing gas-insulated switchgear, the side surface (circumferential surface) of the flange 2 is generally painted in the same manner as the flange 8, but in this embodiment, when the grounding metal fitting 9 is attached, the flange 2 The coating film is removed from the contact portion of the grounding conductive metal fitting 9 on the side surface (peripheral surface). The grounding metal fitting 9 is unpainted at least on the surface in contact with the flange 2. Therefore, the fastening bolt 4 is electrically connected to the flange 2 via the grounding metal fitting 9 and has the same potential (ground potential) as the flange 2.

  An angle θ formed by one side of the L-shaped grounding metal fitting 9 and the other side of the substantially L-shaped grounding metal fitting 9 is an acute angle smaller than 90 degrees, and is slightly smaller than 90 degrees in the illustrated example. As described above, the grounding conductive metal fitting 9 is formed by bending a metal metal fitting, so that the distal end portion 4a of the grounding conductive metal fitting 9 is made of the flange 2 without using any additional parts by utilizing the spring property. The side surface (circumferential surface) can be reliably brought into contact with, and a continuous grounding structure can be secured.

  According to the present embodiment, the grounding conductive metal fitting 9 without surface coating, for example, is attached to the tip part 4a of the fastening bolt 4 that has already been fastened, and the front end part of the grounding conductive metal fitting 9 is attached to the side surface (circumference). By making the structure contact with the non-coating part of the surface), the electrical contact between the fastening bolt 4 and the tank 1 can be ensured with an easy and simple configuration without removing the fastening bolt 4 already fastened. . Thereby, it can prevent that the fastening bolt 4 becomes a floating electrode, and can prevent generation | occurrence | production of a jacket surge. Furthermore, workability is also improved.

  In the present embodiment, by using, for example, a bent metal structure as the grounding conductive metal fitting 9, continuous grounding can be ensured by utilizing the spring property. Further, since there is no need to provide a separate part for ensuring contact at the contact portion between the tip of the grounding conductive metal 9 and the flange 2, the number of parts is reduced, the cost is reduced, and the workability is improved. . The grounding metal fitting 9 can have a structure other than that shown in FIG. 2 and may be other than the illustrated example as long as the connection between the fastening bolt 4 and the flange 2 is achieved.

  A screw rod may be used instead of the fastening bolt 4. That is, threaded rods threaded at both ends are inserted into holes (not shown) provided with the flanges 2 and 8 and the insulating spacer 3, and the tank 1 side has a fastening structure as shown in FIG. On the 7th side, a fastening nut is screwed to the end of the screw rod.

  The tip 4a of the fastening bolt 4 has at least the length of the portion protruding from the fastening nut 5 (FIGS. 2 and 3) for grounding when the fastening washer 6a and the fastening nut 5 are fastened. If it is larger than the thickness of the conductive metal fitting 9, the grounding conductive metal fitting 9 can be attached. However, preferably, the length of the protruding portion is made larger than the sum of the thicknesses of both the grounding conductive metal fitting 9 and the metal fitting fixing nut 10 as shown in the drawing. Note that the use of the same type of fastener fixing nut 10 as that of the fastening nut 5 leads to further cost reduction.

  The present invention is useful as a tank connection structure of a gas insulated switchgear.

DESCRIPTION OF SYMBOLS 1, 7 Tank 2, 8 Flange 3 Insulation spacer 4 Fastening bolt 4a Tip part 5 Fastening nut 6a, 6b Fastening washer 9 Grounding conductive metal fitting 10 Fixing nut

Claims (2)

A first tank having a ground potential, wherein the first flange is provided at one end in the axial direction, and at least surfaces of both sides in the axial direction of the first flange are covered with a coating film;
A second flange opposite to the first flange is provided at one end in the same direction as the axial direction, and a second tank of ground potential in which the entire surface of the second flange is covered with a coating film;
An insulating spacer sandwiched between the first and second flanges;
Bolts or screw rods penetrating the first and second flanges and the insulating spacer, and the first and second flanges screwed into tip portions protruding from the first flanges of the bolts or screw rods. A fastening member including a fastening nut for fastening
The bolt or screw rod is protruded from the fastening nut and is attached to the tip portion through one end thereof, and its one end portion comes into contact with a portion where the coating film on the side surface of the first flange is removed. A metal fitting that maintains the same potential as the first tank;
A fitting fixing nut that is screwed to the tip portion protruding from the fitting and fixes the fitting to the tip portion;
A gas insulated switchgear characterized by comprising: The metal fitting is a structure in which a plate-like metal member is bent in an approximate L shape,
The angle formed by one side of the metal L and the other side is an acute angle,
A portion corresponding to one side of the L-shape of the metal fitting is attached and fixed to the tip.
2. The gas insulated switchgear according to claim 1, wherein a portion corresponding to the other side of the L-shape of the metal fitting is in contact with a portion of the side surface of the first flange from which the coating film has been removed.

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