JPH07122145A - Insulating spacer - Google Patents

Abstract

PURPOSE:To prevent the rotation of metal fittings by the plane notch parts of a shaft directional part of the embedded metal fittings by applying or winding a rubber-like high polymer material to or round the whole circumference of the embedded metal fittings of an insulating spacer, or winding nonwoven fabric, and reducing thermal stress or shaft directional shearing stress by a shock absorbing effect around the embedded metal fittings. CONSTITUTION:In an insulating spacer 1, embedded metal fittings 5 are integrally casted in a plurality almost on the same circumference on the periphery of an insulating subject 1b having the swelling part 3 to support the conductor connecting part 2 in a center side position. Silicon rubber 6 is applied on the whole circumference of the metal fittings 5, and a plane notch 7 is performed on a part. A thick film of the silicon rubber 6 becomes a shock absorbing material of stress. Shrinkage force at casting and hardening time is relieved by the rubber 6. When an insulating spacer 1 changes in the temperature by being fastened to a vessel flange 8, the insulating subject 1b expands and contracts, and the rubber 6 absorbs the stress of an interface between the metal fittings 5. When flatness of the metal fittings is inaccurate, the rubber 6 absorbs shearing stress around the metal fittings 5. Since the plane notch 7 prevents simultaneous rotation of the metal tittings 5 and a bolt 10, the reliability of an apparatus is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating spacer, and more particularly to an insulating spacer in which embedded metal fittings are arranged on the same circumference in the periphery.

[0002]

2. Description of the Related Art Gas-insulated electrical equipment is constructed by housing electrical equipment such as circuit breakers and disconnectors in a metal container filled with insulating gas. An insulating spacer is provided at the connecting portion between the metal containers so as to separate the gas between the containers. In this case, the insulating spacer is arranged so that the flange portion is sandwiched between the flange portions of the adjacent metal containers, and is fastened by bolts penetrating the flange portion of the metal container and the insulating spacer.

For example, FIGS. 3A and 3B are a plan view and a cross-sectional view of a commonly used insulating spacer. As shown in the figure, the insulating spacer 1 has a bulging portion 3 supporting the conductor connecting portion 2 at a position near the center, and an embedded metal fitting for screwing or penetrating a bolt into a peripheral flange portion 4. It has a plurality of 5, 5, ... Such an insulating spacer 1 is generally manufactured by integrally molding the embedded metal member 5 and the insulating main body 1b with an epoxy resin and heating and hardening at a predetermined temperature.

[0004]

However, in the conventional insulating spacer 1, in the cooling step after casting,
The interface peeling phenomenon may occur on the contact surface between the embedded metal member 5 and the insulating main body 1b. This interfacial peeling is especially caused by the embedded metal fitting 5.
This is due to the difference in linear expansion coefficient between the insulating main body 1b and the insulating main body 1b (about 1.5 to 2 times).

The existence of interfacial peeling means that the interfacial peeling progresses due to a mechanical external force such as bending, and further, as shown in FIG.
As shown in FIGS. 4 (A) and 4 (B) in which the portions a and b indicated by the two-dot chain line in FIG. 4 (A) are enlarged, cracks 8 may occur around the embedded metal fitting 5, As a result, the strength of the insulating spacer 1 may be reduced.

Therefore, there has been attempted a method of increasing the adhesiveness at the contact surface between the embedding metal member 5 and the insulating main body 1b by chemical treatment to suppress the interfacial peeling and the progress of the interfacial peeling.
In terms of reliability, it was still not enough.

Further, for example, as shown in the sectional view of FIG.
When the embedded metal 5 is fastened to the container flange 9 and cannot be freely expanded and contracted in a state where the embedded metal 5 is strongly restrained by the flange portion 9 and the bolt 10, when the humidity of the insulating spacer rises or falls, A crack may occur at the interface of the fitting 5.

Further, as shown in the sectional view of FIG. 6, when the end surfaces of the embedded metal fitting 5 are not on the same plane, the fastening force of the flange portion 9 causes shearing force in the embedded metal fitting 5 to cause cracks. There is a fear.

As described above, in the conventional insulating spacer, there is a possibility that interface peeling and cracks may occur between the embedded metal fitting of the flange portion and the insulating main body.

The present invention has been made in consideration of the above circumstances, and an object thereof is to prevent peeling stress generated between an embedded metal member and an insulating main body portion due to thermal stress and axial stress due to flange fastening. Another object of the present invention is to provide an insulating spacer for gas-insulated equipment, which is reduced in length and prevents cracks from occurring, and has high long-term reliability.

[0011]

In order to achieve the above object, the first aspect of the present invention is that the conductor disposed in a grounding container in which an insulating gas is filled is insulated and supported in the grounding container.
In an insulating spacer in which a plurality of embedded metal fittings having female threads are integrally cast around substantially the same circumference around an insulating main body, an elastic polymer material is applied or wrapped around the entire circumference of the embedded metal fitting. And In addition, claim 2 of the present invention
Insulates and supports a conductor placed in a grounding container filled with insulating gas in this grounding container, and integrally casts a plurality of embedded metal fittings having female threads on the same circumference around the insulating main body. In the insulating spacer described above, a non-woven fabric is wound around the entire circumference of the embedded metal fitting. Further, a third aspect of the present invention is characterized in that, in the insulating spacer according to the first or second aspect, a plane notch is provided in a part of the cylindrical embedded metal article in the axial direction.

[0012]

With the above-described structure, thermal stress or axial shear stress can be reduced due to the buffering effect around the embedded fitting, and further, the rotation of the embedded fitting that occurs when bolts are fastened is due to the presence of the notch. It can be prevented.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of one embodiment of an insulating spacer according to the present invention. As shown in the figure, the insulating spacer 1 is
A plurality of embedded metal fittings 5 are integrally cast on substantially the same circumference in the periphery of an insulating main body 1b having a bulging portion 3 for supporting the conductor connecting portion 2 at a position near the center. The embedded metal fitting 5 embedded in the flange portion 4 of the insulating spacer 1 is shown in FIG.
As shown in the cross-sectional views and plan views of (A) and (B), the silicone rubber 6 is applied to the entire circumference, and the flat surface notch portion 7 is provided in a part thereof. That is, the embedded fitting 5 and the insulating main body 1
A thick silicone rubber 6 is applied to the interface of b, and this serves as a buffer material for stress.

The silicone rubber 6 alleviates the shrinkage force generated during cast curing. Further, when the temperature of the insulating spacer 1 is tightened in the container flange 8 and rises or falls, the embedded metal member 5 is restrained by the container flange 8, but the insulating main body 1b expands and contracts. However,
Since there is the silicone rubber 6, the stress generated at the interface of the embedded fitting 5 can be absorbed.

Even when the flatness of the embedded metal fitting 5 is not accurate, since the silicone rubber 6 serves as a cushioning material, when the container flange 8 is tightened, the axial direction of the end surface of the embedded metal fitting 5 is on the same plane. Since the load to be set can be absorbed, no shearing force is generated around the embedded fitting 5. When the bolt is tightened, the flat cutout 7 has the embedded metal fitting 5 and the bolt 1
This is provided to prevent 0s from rotating at the same time.

[0016]

As described above, according to the present invention,
Since the rubber-like polymer material is applied or wrapped around the embedding metal fitting of the insulating spacer, or a non-woven fabric is wound around the embedding metal fitting, the thermal stress or the axial shearing stress can be reduced by the buffering effect around the embedding metal fitting. Furthermore, since the embedded metal fitting has a planar cutout in a part in the axial direction, the rotation of the embedded metal fitting that occurs when bolts are fastened is prevented, and the reliability of the device is improved.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

2A and 2B are a cross-sectional view and a plan view of the embedded metal article of FIG. 1, respectively.

FIG. 3A is a plan view of a conventional insulating spacer, and FIG. 3B is a sectional view of FIG.

4 (A) is a detailed view of part a of FIG. 3 (A), and FIG. 4 (B) is a detailed view of part b of FIG. 3 (A).

FIG. 5 is a diagram for explaining a stress generated in the vicinity of a conventional embedded fitting.

FIG. 6 is a view for explaining a stress generated in the vicinity of another conventional embedded metal fitting.

[Explanation of symbols]

1 ... Insulation spacer, 1b ... Insulation main body, 2 ... Conductor connection part,
3 ... Bulging part, 4 ... Flange part, 5 ... Embedded metal fitting, 6 ... Rubber-like polymer material or non-woven fabric, 7 ... Plane notch part, 8 ...
Crack, 9 ... container flange, 10 ... bolt.

Claims (3)

[Claims] 1. A plurality of embedding metal fittings, each of which has a conductor disposed in a grounding container in which an insulating gas is filled and which is insulated and supported in the grounding container, and has a female screw on substantially the same circumference around the insulating main body. An insulating spacer in which a polymeric material having elasticity is applied or wound around the entire circumference of the embedded spacer. 2. A plurality of embedding metal fittings, which electrically insulate and support a conductor arranged in a grounding container in which an insulating gas is filled, and which have female threads on substantially the same circumference around the insulating main body. An insulating spacer cast in one piece, wherein a non-woven fabric is wound around the entire circumference of the embedded metal fitting. 3. The insulating spacer according to claim 1, wherein a plane cutout is provided in a part of the cylindrical embedded metal article in the axial direction.