JPH0745146A - High-molecular composite insulator and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a high-molecular composite insulator which is low in cost and has excellent interfacial water-tightness, withstand voltage characteristics, anti-pollution characteristics and insulative property, and a method for manufacturing the same. CONSTITUTION:A base material sheet composed of unvulcanized rubber or thermoplastic resin is adhered onto the outer periphery of an insulative bar-like core body 1 with an adhesive layer 2 interposed therebetween, to thereby form a base material layer 3. Then, cylindrical insulative units 4 each having one sheet of umbrella on level flange is fitted over the outer periphery of the insulative bar-like core body 1 formed thereon with the base material layer 3. Then, the insulative bar-like core body 1 fitted thereover with the cylindrical insulative body 4 is heated to thereby integrate the insulative bar-like core body 1, adhesive layer 2, base material layer 3 and cylindrical insulative body 4 with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer composite insulator used as a high voltage insulator such as an insulator.

[0002]

2. Description of the Related Art Recently, an insulating rod-shaped core made of a highly rigid material such as glass fiber reinforced plastic (hereinafter abbreviated as "FRP"), and high weather resistance and non-tracking characteristics fitted on the outer periphery of the core. A polymer composite insulator composed of an outer cover and a shell is used as a substitute for a conventional inorganic insulator (porcelain insulator). The outer cover of the polymer composite insulator has a configuration in which a cap is formed on the outer periphery of the tubular insulator, and is provided to extend the creeping insulation distance of the polymer composite insulator. This kind of polymer composite insulator
Usually, electrode fittings are attached to both ends thereof for use.

[0003]

The watertightness at the interface between the insulating rod-shaped core and the outer cover (hereinafter referred to as "interfacial watertightness") is important for affecting the insulating properties of the polymer composite insulator. It is a characteristic. That is, since the linear expansion coefficients of the insulating rod-shaped core body and the constituent material of the outer cover body are different from each other, stress is generated at the interface due to a change in ambient temperature. If the interface shifts or peels off due to this stress, the adhesiveness between the insulating rod-shaped core body and the outer covering body deteriorates, and the water-tightness of the interface deteriorates. As a result, water penetrates into the interface, an electric conduction path is formed, and an accident such as defective insulation occurs. Therefore, it is desired to solve the problem of interfacial watertightness in the polymer composite insulator.

In order to solve the above-mentioned problems, for example, a heat-shrinkable cylindrical insulator having a plurality of caps is used as the outer jacket, and this is applied to the outer periphery of the insulating rod-shaped core through an adhesive layer. A method for producing a polymer composite insulator has been proposed in which the insulating rod-shaped core body and the tubular insulator are integrated by heat vulcanization after external fitting (Japanese Patent Publication No. 58-51367). According to this method, the pressure-sensitive adhesive layer functions as a stress relaxation layer, so that a polymer composite insulator having excellent interfacial watertightness can be produced. However, in this method, since a plurality of caps are continuously provided on the outer circumference of one cylindrical insulator, the shape of the caps is limited to a simple shape protruding perpendicularly to the cylindrical insulator. Have the problem.
Therefore, it is difficult to manufacture a polymer composite insulator having a complicated shape such as a projection formed on a shade in order to extend the creepage insulation distance of the polymer composite insulator and improve salt damage resistance. In addition, due to the structure of the mold used for producing a tubular insulator having a plurality of shades, two parting lines (burr marks) are formed in the longitudinal direction of the tubular insulator. Have. This parting line has a shape along the electric field direction of the polymer composite insulator, and becomes a factor that deteriorates the withstand voltage characteristics of the polymer composite insulator. Further, when the polymer composite insulator is used outdoors, the parting line acts as a water groove and causes tracking damage or erosion damage.

On the other hand, as a method for solving the problem of the parting line, there is the following method. That is, FR
The ethylene-propylene rubber (EPR) and ethylene-propylene-diene rubber (E
PDM), isobutylene-isoprene rubber (IIR), or other rubber is extruded to form a rubber tube layer serving as a tubular insulator. Then, a single rubber cap is directly fitted on the outer circumference of the rubber tube layer, and then the cap is contracted, and then the rubber tube is vulcanized to be integrated with the cap. Has been proposed (Japanese Patent Publication No. 4-75).
No. 604). Further, the surface of the FRP insulating rod-shaped core is subjected to silane treatment, and a silicone rubber layer is extruded and coated thereon. On the other hand, a manufacturing method has also been proposed in which a single cap is expanded in the radial direction in advance, and this is press-fitted onto the outer periphery of the silicone rubber layer, and then the silicone rubber layer is vulcanized and integrated (Japanese Patent Publication No. 63-3407). Issue). In these methods, since the caps are formed one by one, the parting line is formed along the circumferential direction of the caps, which does not adversely affect the withstand voltage characteristics and the like of the polymer composite insulator. However, since the rubber layer is extruded, it is difficult to form an adhesive layer that can serve as a stress relaxation layer between the insulating rod-shaped core and the outer cover. That is, in the above two manufacturing methods, if an attempt is made to form an adhesive layer, special steps, facilities, equipment, etc. are required, which causes a problem that the cost of the polymer composite insulator obtained increases. Therefore, the above method solves the problem of the parting line, but has not yet solved the problem of the decrease in the water tightness of the interface due to the change of the ambient temperature.

The present invention has been made in view of the above circumstances, and provides a low-cost polymer composite insulator excellent in interfacial watertightness, withstand voltage characteristics, salt damage resistance characteristics, and insulation properties, and a method for producing the same. Is its purpose.

[0007]

In order to achieve the above object, the present invention has a base material layer formed on the outer circumference of an insulating rod-shaped core, and a single cap is provided on the outer circumference of the base material layer. A polymer composite insulator, in which a tubular insulator provided is externally fitted, wherein a pressure-sensitive adhesive layer is formed between the insulating rod-shaped core body and the base material layer. In summary, a polymer composite insulator in which a base material layer is formed on the outer periphery of an insulating rod-shaped core body, and a cylindrical insulator having a cap is externally fitted on the outer periphery of the base material layer. In the method of manufacturing, the step of forming a base material layer by adhering a base material sheet made of unvulcanized rubber or a thermoplastic resin to the outer periphery of the insulating rod-shaped core body via an adhesive layer, and forming the base material layer. Step of externally fitting a tubular insulator provided with a cap on the outer periphery of the insulated rod-shaped core body, and the insulating rod-shaped core body to which the tubular insulator body is externally fitted The insulating bar-like core heated, the adhesive layer, the production method of the polymer composite insulator comprising the step of integrating the base layer and the cylindrical insulator and the second aspect.

[0008]

That is, the present inventors have conducted a series of studies in order to solve the problems of forming the parting line and the adhesive layer. In the process, I remembered using a tubular insulator with a cap. As a result, a base material layer is formed on the outer circumference of the insulating rod-shaped core body via an adhesive layer, and a tubular insulation body having a single cap is externally fitted to the outer circumference of the base material layer for heat treatment. It has been found that the application makes it possible to easily form the pressure-sensitive adhesive layer serving as the stress relaxation layer, and the shape of the shade can also be a shape having projections. And
The inventors have found that the parting line of the tubular insulator provided with the above-mentioned one cap is formed along the circumferential direction of the cap and reached the present invention. According to the present invention, interfacial watertightness, withstand voltage characteristics,
It is possible to provide a low-cost polymer composite insulator excellent in salt damage resistance and insulation properties and a method for producing the same.

Next, the present invention will be described in detail based on examples.

[0010]

EXAMPLE FIG. 1 is a sectional view showing an example of a polymer composite insulator of the present invention. Reference numeral 1 denotes a cylindrical FRP insulating rod-shaped core body, and a base material layer 3 is formed on the outer periphery of the core body 1 with an adhesive layer 2 interposed therebetween. Then, the cylindrical insulator 4 provided with one cap is externally fitted on the outer periphery of the base material layer 3. Above Kasae 7
Is composed of two types of long and short shades 7a and 7b having different diameters, and long and short shades 7a and 7b are alternately provided. Further, electrode fittings 6 are provided with O-rings 9 on both ends of the core 1.
Is attached through. Then, the electrode fitting 6
The core body 1 and the core body 1 are integrated by an adhesive 8.

This polymer composite insulator can be manufactured, for example, as follows. That is, first, in FIG.
As shown in, the base material layer 3 is formed on the outer periphery of the insulating rod-shaped core body 1 via the adhesive layer 2. The insulating rod-shaped core 1 is
It may be cylindrical or columnar as shown in FIG. The base material layer 3 can be formed by winding and adhering a base material sheet made of unvulcanized rubber or thermoplastic resin around the outer circumference of the insulating rod-shaped core body 1.
Examples of the unvulcanized rubber include silicone rubber, EPR, E
Examples of the thermoplastic resin include PDM and IIR.
Examples include polyolefin-based thermoplastic resins. The unvulcanized rubber and the thermoplastic resin are used alone or in combination. Among these, EPDM as unvulcanized rubber,
As a thermoplastic resin, ethylene-vinyl acetate copolymer (E
It is preferable to use VA). The pressure-sensitive adhesive layer 2 can be formed by previously bonding the pressure-sensitive adhesive sheet to either the base sheet or the core body 1. The pressure-sensitive adhesive layer 2 functions as a stress relaxation layer, which prevents a decrease in interfacial watertightness. As the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 2, it is preferable to use a hot-melt type pressure-sensitive adhesive containing a thermoplastic resin, specifically, a polyolefin-type thermoplastic resin or the like can be mentioned. Among these, EVA is used. It is preferable. By using such an adhesive, the fluidity of the adhesive layer after heat vulcanization is increased, and the FRP
The surface of the insulating rod-shaped core 1 is sufficiently wetted, and the water-tightness and airtightness of the interface are further improved. The thickness of the adhesive layer 2 is set in the range of 0.1 to 1.0 mm, preferably 0.3 to 0.7 mm. That is, when the thickness of the adhesive layer 2 is less than 0.1 mm, it cannot function as a stress relaxation layer, and when it exceeds 1.0 mm, it is tightened due to shrinkage of the tubular insulator 4 during heat vulcanization. This is because the thickness of the pressure-sensitive adhesive layer 2 becomes non-uniform due to the pressure, and the pressure-sensitive adhesive may leak to the outside. The thickness of the base material layer 3 is set in the range of 0.3 to 1.0 mm, preferably 0.4 to 0.8 mm. That is, when the thickness of the base material layer 3 is less than 0.3 mm, the base material layer 3 may tear due to the tightening pressure when the cylindrical insulator 4 is heat-shrinked, and the adhesive layer 2 may protrude.
This is because if it exceeds 0 mm, a large step may occur at the joining portion of the base material sheet when the base material sheet is wound, and a void may be formed. Further, the organic component of the base material layer 3 and the organic component of the tubular insulator 4 are preferably the same. As such organic components, silicone rubber, E
PR, EPDM, ethylene-ethyl acrylate copolymer (EEA) and the like can be mentioned, and a mixture thereof is preferable. In this way, by making the organic components of the two members the same, fusion in the heat treatment can be easily performed, and the adhesiveness between them can be improved. The base material sheet and the pressure-sensitive adhesive sheet used for forming the base material layer and the pressure-sensitive adhesive layer can be produced as follows. That is, an unvulcanized rubber or a thermoplastic resin which is a material for forming a base sheet and an adhesive which is a material for forming an adhesive sheet are kneaded by a roll, a Banbury mixer or the like. Then, the base material sheet and the pressure-sensitive adhesive sheet can be produced by rolling the kneaded product with a calendar roll or extrusion molding to form a sheet.

On the other hand, as shown in FIG. 3, a cylindrical insulator 4 having one cap 7 and having overlapping portions 13a and 13b at both ends is prepared. It is preferable to use a heat-shrinkable cylindrical insulator 4. This heat-shrinkable tubular insulator can be obtained as follows. That is,
A rubber material such as silicone rubber, EPR, EPDM, EVA, EEA, etc., preferably a mixture thereof is vulcanized and molded into a predetermined shape in a mold. Then, as shown in FIG. 5, the inner diameter is enlarged at a temperature equal to or higher than the softening point so that the material has heat recoverability. In this way, the heat-shrinkable tubular insulator 4a can be obtained. At this time, the cylindrical insulator 4
The inner diameter of a when contracted needs to be smaller than the outer diameter of the insulating rod-shaped core 1. That is, by doing so, a sufficient tightening pressure of the tubular insulator 4 due to heat shrinkage can be obtained, the adhesion between the tubular insulator 4 and the base material layer 3 is improved, and the interface watertightness is improved. Because it will be superior.
Further, according to the present invention, it is possible to use the shade 7 having the protrusions 5 as shown in FIG. By using the tubular insulator 4b provided with such a cap, the creeping insulation distance is extended and the salt damage resistance is also improved.

Then, as shown in FIG. 6, the heat-shrinkable cylindrical insulator 4a is fitted onto the outer periphery of the insulating rod-shaped core body 1 on which the base material layer 3 is formed via a gap 10. At this time, when a plurality of tubular insulators 4 are externally fitted, they are fitted in a vertically connected state so that the overlapping portions 13a and 13b at their ends are combined. This external fitting eliminates the possibility that the base material layer is exposed on the surface. Then, it is heated in a vacuum dryer to shrink the tubular insulator 4, melt the adhesive layer 2,
By vulcanizing and fusing the base material layer 3 at the same time, the insulating rod-shaped core body 1, the adhesive layer 2, the base material layer 3 and the tubular insulator 4 are formed.
Unify. Thus, the polymer composite insulator as shown in FIG. 7 can be manufactured.

Further, O is added to both ends of the polymer composite insulator.
By attaching the electrode fitting 6 via the ring 9,
A polymer composite insulator product as shown in FIG. 1 can be made. In addition, the electrode fitting 6 for the polymer composite insulator
Can be attached with the adhesive 8. Further, the polymer composite insulator and the electrode fitting 6 may be threaded and fixed with screws. Further, the mounting portion 11 of the electrode fitting 6 may be covered with a watertight cover along the circumferential direction of the polymer composite insulator. Thereby, the watertightness of the mounting portion 11 is improved, and the weather resistance and insulating property of the polymer composite insulator are improved.

Further, as shown in FIG. 8, a current limiting element 12 having a non-linear voltage-electric field characteristic such as a zinc oxide element is held in the insulating rod-shaped core 1 by using a spring 14. By filling, the polymer composite insulator of the present invention can be used as a lightning arrester. Thus, when using the polymer composite insulator as a lightning arrester,
It is desirable that the water absorption of the base material layer 3 be smaller than that of the tubular insulator 4. That is, a current limiting element 1 such as a zinc oxide element
2 greatly changes its characteristics due to the adsorption of water. However, since the tubular insulator 4 usually contains a metal hydrate such as aluminum hydroxide or magnesium hydroxide as a tracking resistance improver, it is easy to absorb water. Therefore, the water easily diffuses into the insulating rod-shaped core body interior 1. Therefore, if the base material layer 3 having a water absorption rate smaller than that of the tubular insulator 4 is formed, the insulating rod-shaped core body 1 is formed.
It is possible to suppress the diffusion of moisture into the interior, and the characteristics of the current limiting element 12 are not affected by moisture.

[0016]

As described above, the present invention has as its first gist a polymer composite insulator having an adhesive layer between an insulating rod-shaped core and a base material layer, and has an outer periphery of the insulating rod-shaped core. A base material layer via an adhesive layer on the base material layer, and a cylindrical insulator having a cap is externally fitted to the outer periphery of the base material layer and subjected to heat treatment to obtain the insulating rod-shaped core body, A second gist is a method for producing a polymer composite insulator that integrates an adhesive layer, a base material layer, and a tubular insulator. Therefore, the polymer composite insulator of the present invention is provided with the adhesive layer serving as the stress relaxation layer, and thus has excellent interfacial watertightness. Further, since the shape of the shade can also be a shape having protrusions, the creepage insulation distance becomes long, and the salt damage resistance is also excellent. Moreover, since the parting line of the cylindrical insulator is formed along the circumferential direction of the shade, the current passage is not formed by the water groove,
In addition, the withstand voltage characteristic is also improved. Further, a heat-shrinkable one is used as the tubular insulator, the organic component of the tubular insulator and the organic component of the base material layer are made the same, and unvulcanized rubber or the like is used as a material for forming the base material sheet. When these are heat-treated and used, the shrinkage of the tubular insulator, the vulcanization of the base material layer, and the fusion of the base material layer and the tubular insulator occur at the same time to integrate them, so each member is firmly bonded. Thus, it is possible to obtain a polymer composite insulator having excellent airtightness and watertightness. Then, by filling the inside of the polymer composite insulator of the present invention with a current limiting element having a non-linear voltage-current characteristic, it can be used as a lightning arrester. Also,
The manufacturing method of the polymer composite insulator of the present invention is a simple manufacturing method, and it is possible to form the adhesive layer without using special steps, equipment and devices. Therefore, the obtained polymer composite insulator has a low cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a polymer composite insulator of one embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which a base material layer is formed on the outer periphery of an insulating rod-shaped core body with an adhesive layer interposed therebetween.

FIG. 3 is a cross-sectional view of a tubular insulator having a cap used in an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a state in which the cylindrical insulator is enlarged in a radial direction.

FIG. 5 is a cross-sectional view of a tubular insulator having a cap with protrusions.

FIG. 6 is a cross-sectional view showing a state in which a tubular insulator is externally fitted around the outer periphery of an insulating rod-shaped core body on which a base material layer and an adhesive layer are formed.

FIG. 7 is a cross-sectional view showing a state in which the insulating rod-shaped core body on which the tubular insulator is fitted is heated and integrated.

FIG. 8 is a cross-sectional view showing a state in which an insulating rod-shaped core body is filled with a current limiting element.

[Explanation of symbols]

 1 Insulating Rod-shaped Core 2 Adhesive Layer 3 Base Layer 4 Cylindrical Insulator

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsunobu Sonoda 1-2 1-2 Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation

Claims (7)

[Claims] 1. A polymer composite insulation in which a base material layer is formed on the outer periphery of an insulating rod-shaped core body, and a tubular insulation body having a single cap is externally fitted on the outer periphery of the base material layer. A polymer composite insulator, characterized in that an adhesive layer is formed between the insulating rod-shaped core and the base material layer. 2. The polymer composite insulator according to claim 1, wherein the parting line of the tubular insulator having a single cap is formed along the circumferential direction of the cap. 3. The polymer composite insulator according to claim 1 or 2, wherein the water absorption of the base material layer is smaller than that of the tubular insulator having one cap. 4. An insulating rod-shaped core body is filled with a current limiting element having a non-linear voltage-current characteristic.
The polymer composite insulator according to any one of 1. 5. A polymer composite insulation in which a base material layer is formed on the outer periphery of an insulating rod-shaped core body, and a tubular insulation body having a single cap is externally fitted on the outer periphery of the base material layer. In the body manufacturing method,
A step of forming a base material layer by adhering a base material sheet made of unvulcanized rubber or a thermoplastic resin to the outer periphery of an insulating rod-shaped core body via an adhesive layer, and an insulating property in which the base material layer is formed. A step of externally fitting a tubular insulator provided with a cap on the outer periphery of the rod-shaped core body; and heating the insulating rod-shaped core body with the tubular insulator fitted thereinto to heat the insulating rod-shaped core body, A method for producing a polymer composite insulator, comprising a step of integrating an adhesive layer, a base material layer and a tubular insulator. 6. The cylindrical insulator having one cap is heat-shrinkable, and the inner diameter of the cylindrical insulator when contracted is smaller than the outer diameter of the insulating rod-shaped core. Polymer composite insulator manufacturing method. 7. The organic component of the tubular insulator having a single cap and the organic component of the base material layer are the same.
A method for producing the polymer composite insulator described.