JPH01246723A - Resin mold part for high voltage insulation and its manufacture - Google Patents

Abstract

PURPOSE:To improve the reliability to the SF6 resolution gas by spreading anticorrosive particles to whose surface minute resin particles are dispersed on the surface of a casting resin insulating base material, or attaching the anticorrosive particles on the surface of the casting insulating base material through a metal mold. CONSTITUTION:To a casting resin insulating base material 11, an anticorrosive layer 16 is formed with anticorrosive particles such as alumina powder 15 to compose a resin-mold part for high voltage insulation purpose. As a result, when it is used in the ambiance of the SF6 resolution gas, the anticorrosive layer protects the casting resin insulating base material, and the mechanical and the electrical properties of the high voltage insulating resin-mold part are never spoiled. Moreover, anticorrosive particles such as alumina powder on whose surface resin superminute particles 14 are dispersed is sprayed on a high temperature metal mold 17, and attached to the surface of the base material 11 in the casting process. As a result, a uniform anticorroside layer can be formed on the casting resin insulating base material.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a resin molded component for high voltage insulation and a method for manufacturing the same, and in particular, a resin molded component for high voltage insulation that is suitable for SF6 gas resistance. and its manufacturing method.

(Prior art and problems to be solved by the invention) In general, cast resin insulation base materials for high voltage insulation resin molded parts have thermal shock resistance, curing shrinkage, abrasion resistance, heat resistance,
Alumina powder (A1203), silica powder (S102) for improved chemical resistance, mechanical and electrical properties
, glass fiber, calcium carbonate, and other inorganic fillers are added.

However, the sulfur hexafluoride gas (sulfur hexafluoride gas) used as the insulating medium for high-voltage electrical equipment makes these high-voltage insulating resin molded parts
When using in an atmosphere of SF (hereinafter referred to as gas),
SF6 gas becomes SF4.82 F due to arc, corona, heat, etc.
2. Since it is decomposed into SOF4, SO2F2, etc., it causes a chemical reaction with the inorganic filler such as the silica powder, resulting in a significant decrease in insulation performance.

In other words, molded parts of bisphenol-based epoxy resin (
A), molded part in which bisphenol-based epoxy resin is filled with alumina powder (B), molded part in which bisphenol-based epoxy resin is filled with silica powder <C>, and molded part in which bisphenol-based epoxy resin is filled with glass fiber (D) and put them at a gas pressure of 4 at
SF6 gas is placed in a sealed container (not shown) filled with SF6 gas, and a large current arc is applied with a current duration of 60 as, a number of discharges 10 times, and a time interval of 3 to 5 minutes as one cycle.
The decomposition gas of No. 8 was generated in a closed container, and a characteristic diagram of insulation resistance and discharge time was obtained. These relationships are as shown in Figure 8 for molded parts (A) and molded parts (B).
The insulation resistance maintained 1013Ω even after 5 hours, and the electrical properties were satisfactory, but the mechanical properties were poor.
Furthermore, although the molded parts (C) and molded parts (D) have good mechanical properties, the insulation resistance decreases to 10.0 after 5 hours. The resistance decreased to 106Ω, and the electrical characteristics were not satisfied. Therefore, if these cast resin insulating base materials are used as they are, S
It cannot be used in an F6 gas atmosphere.

One possible way to prevent insulation degradation of resin molded parts for high voltage insulation due to SF6 gas is to coat the surface of the resin molded parts with SF, a strong resin material that does not decompose with gas. These resins also have problems such as peeling phenomenon or pinhole formation on the surface of the resin molded parts, making it impossible to use them with sufficient reliability for a long period of time.

Another method is to use a strong filler that cannot be decomposed by S Fe gas in the resin molded parts. This material includes alumina powder (AIO), CaF
2. Although there are CaSO4, BN, etc., CaF2 is preferred from the viewpoint of mechanical strength.

Since CaSO4, BN, etc. are not suitable for practical use, alumina powder (A1203) is used, but this material has the problem of being brittle and having low strength against thermal cycles.

Another possible method is a two-stage casting method in which the inside of the resin molded part is made of a mechanically strong resin material, and the outside is made of a resin that is resistant to SF6 gas, but this method requires the use of multiple resins. is used, new interfaces are created between each resin, and these parts peel off, reducing mechanical and electrical properties, making it impossible to obtain reliable products.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, it is an object of the present invention to provide a high-voltage insulating resin molded component that is not corroded by SF6 decomposition gas and has sufficient reliability, and a method for manufacturing the same.

[Structure of the invention]

(Means for Solving the Problems) According to the present invention, corrosion-resistant particles in which ultrafine resin particles are dispersed on the surface of a cast resin insulating base material are applied.

In addition, corrosion-resistant particles with ultrafine resin particles dispersed on the surface are attached to the inner surface of a high-temperature mold, a casting resin insulating base material is injected into the mold, and the corrosion-resistant particles are applied to the surface of the casting resin insulating base material. It is made to be attached to the surface.

(Function) In an atmosphere of SF6 gas, especially in an atmosphere of SF6 decomposition gas, high-voltage insulating resin molded parts are protected by corrosion-resistant particles in which ultrafine resin particles are dispersed, and the high-voltage insulating resin molded parts inside are protected from corrosion. This ensures creepage insulation resistance and maintains mechanical properties.

Corrosion-resistant particles in which ultrafine resin particles are dispersed are attached to the inner surface of the mold, and a casting resin insulating base material is injected into this mold, so that the corrosion-resistant particles are uniformly attached to the surface of the casting resin insulating base material. A sufficiently reliable cast resin insulating base material can be obtained even in an atmosphere of SF6 decomposition gas.

In addition, since the mold is heated to a high temperature and the corrosion-resistant particles in which ultrafine resin particles are dispersed are attached, and the casting resin insulating base material is injected into the mold, the corrosion-resistant particles are attached to the surface of the casting resin insulating base material. It is easy to attach and strengthens the bond.
Sufficient strength against peeling, thermal cycling, etc. is also ensured.

(Example) An example in which the resin molded component for high voltage insulation of the present invention is applied to a high voltage insulator will be described below with reference to the drawings.

In FIG. 1, reference numeral 10 denotes a high-pressure insulator, which is formed into a cylindrical shape by casting bisphenol-based epoxy resin 11 containing short glass fibers and silica powder to provide mechanical strength. The cylindrical outer surface of this insulator 10 is provided with an uneven portion 12 to increase the insulation area, and fixing metal inserts 13 and 13 with screw holes etc. (not shown) are provided at both upper and lower ends. . A corrosion-resistant layer 16 resistant to SF6 decomposition gas, the details of which will be described later, is formed on the entire outer surface, and this corrosion-resistant layer 16 is made of corrosion-resistant particles 14 such as alumina powder and highly dispersed acrylic ultrafine powder. A corrosion-resistant material in which ultra-fine resin particles 15 such as highly dispersed acrylic ultra-fine powder are attached to the surface of corrosion-resistant particles 14 such as alumina powder by mixing with ultra-fine resin particles 15 such as (see Fig. 2) It is made up of.

First, the mold 17 is heated to a high temperature of about 200° C., and the corrosion-resistant material is sprayed into the cavity 171 of the mold 17 using the spray gun 18 (FIG. 3). That is, when compressed air is sent to a pipe 20 connected to a compressed air source (not shown), the material-resistant material is sucked from a pipe 21 connected to a tank (not shown) that stores the material-resistant material, and the material-resistant material is sucked together with the compressed air. It is sprayed into the cavity 17a of the hot mold 17.

In this way, when the corrosion-resistant particles are sprayed into the cavity 17a of the mold 17, the resin on the surface of the corrosion-resistant particles is softened by the temperature of the mold 17, and the corrosion-resistant particles 14 are transferred to the cavity 17a of the mold 17 through this resin. attached to. The thickness of this adhesion layer is determined depending on the conditions of the equipment used, but is generally about 20 μm, as explained in FIG. 6.

The mold 17 is normally as shown in FIG. The cavities 17a of the mold 17 sprayed with anti-corrosive material using the above method are arranged so as to face each other, and metal inserts 13.13 are inserted into the center of both upper and lower ends. From the injection port 22 of the mold 17 assembled in this way, for example, short glass fibers 2.
3. A casting resin insulating base material made of bisphenol-based epoxy resin 11 filled with silica powder 24 is injected, and the first
The high voltage insulator 10 shown in the figure is formed.

In this manufacturing process, the bisphenol-based epoxy resin 11 becomes liquid when heated to a high temperature, and due to its capillary phenomenon, the corrosion-resistant particles 14 of the alumina powder and the highly dispersible acrylic resin It freely enters the gap between the fine particles 15 and the corrosion resistant material, and reaches the cavity 17a of the mold 17, forming a continuous matrix-like strong bond between the bisphenol-based epoxy resin 11 and the corrosion resistant material (see Figure 5). .

During this bonding, the bisphenol-based epoxy resin 11, which becomes liquid at high temperatures, freely enters between the corrosion-resistant particles 14 and the highly dispersible acrylic resin ultrafine particles 15.
The solid matter of short glass fibers 23 and silica powder 24 remains within the cast resin insulating base material and is not exposed to the surface.

When the bisphenol-based epoxy resin 11 hardens after molding, a corrosion-resistant layer 16 of corrosion-resistant particles 14 and highly dispersed acrylic resin ultrafine particles 15 is formed on the surface of the insulator 10, and the cast resin insulation inside is protected from SF6 decomposition gas. Protects the base material and maintains the electrical properties of the surface. In addition, since the corrosion-resistant layer 16 and the silica powder 24 are bonded together as a continuous matrix by the bisphenol-based epoxy resin 11, the adhesion between the corrosion-resistant layer 16 and the internal casting resin insulating base material becomes strong. It does not peel, blister, crack, etc. even in the face of sudden temperature changes.

The high-pressure insulator 10 thus formed was subjected to an erosion test using SF and cracked gas. The test was conducted using SF6 gas at 0. The relationship between the thickness of the corrosion-resistant layer 16 and the eroded layer was investigated by holding it at a gauge pressure of 3 kgf/e containing 1% I Vo for 10 days. The results are shown in FIG. 6, and it was found that when the thickness of the corrosion-resistant layer 16 was set to 20 μm or more, the erosion layer became 1 μm or less, and the insulator was not eroded by SF6 gas.

Based on these results, the following three types of 10 kV insulating insulators shown in FIG. 7 were manufactured and comparative tests were conducted.

A1 casting resin insulating base material is made of bisphenol-based epoxy resin, filled with 250 phr of glass fiber and 200 phr of silica powder,
This surface is coated with a corrosion-resistant layer of 100 μm alumina particles, and the B1 cast resin insulating base material is made of bisphenol-based epoxy resin, which is filled with 250 phr of glass fiber and 200 phr of silica powder (the anti-corrosion layer was provided by personnel). (excluded) C1 casting resin insulating base material made of bisphenol-based epoxy resin filled with 250 phr of alumina powder. With IVo1%, 3,
A characteristic test was conducted in which the sample was maintained at a gauge pressure of Okgf/am for 10 days.

Initially, the insulation resistance of each insulator was 1015Ω, but after the test, the insulation resistance of insulator B decreased to 108Ω, but the insulation resistance of the other two types of insulators remained at 1013Ω.

Next, these 9 Chinese insulators A, B, and C were heated at 0°C for 1 hour.]
l') (10 1 hour liquid phase cooling cycle at +T
A bending strength test of 1 Jit was conducted. In accordance with JIR, a static bending load was applied to the tip 50a+m of the insulator using a cantilever type loading method, and the fracture #
J/Il1 weight is calculated.

] (The average initial breaking strength of Isles A, B, and C was 800.780.640 kgf, respectively, but after the preheating cycle, the strength of Isles C1, that is, the one filled with only alumina powder, decreased. decreased to an average of 420 kgr, which was below the load capacity of 600 kgf, but other insulators A,
In case of B, the strength did not decrease even after the cooling/heating cycle.

Furthermore, no blistering, cracking, or peeling on the surface of these insulators A and B was observed.

As is clear from the above results, a cast resin insulating base material filled with glass fiber and silica powder and a corrosion-resistant layer containing alumina particles on the surface has superior mechanical and electrical properties. This makes it ideal for insulators such as high-voltage insulators.

〔Effect of the invention〕

In the present invention, since a corrosion-resistant layer is formed on a casting resin insulating base material using corrosion-resistant particles such as alumina powder to form a high-voltage insulating resin molded part, the corrosion-resistant layer can be used in an atmosphere of SF8 decomposition gas. protects the cast resin insulating base material and does not impair the mechanical and electrical properties of high voltage insulating resin molded parts.

In addition, corrosion-resistant particles such as alumina powder with ultrafine resin particles dispersed on the surface are sprayed onto a hot mold, and this allows them to adhere to the surface of the cast resin insulating base material when the cast resin insulating base material is cast. Therefore, a uniform corrosion-resistant layer can be formed on the cast resin insulating base material.

Moreover, since the cast resin insulating base material penetrates between the corrosion-resistant particles, the corrosion-resistant particles and the cast resin insulating base material are firmly bonded after the cast resin insulating base material is cured, and the corrosion-resistant layer is protected against sudden temperature changes. No peeling, blistering, cracking, etc. will occur.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of an insulator that is an embodiment of the insulating component of the present invention, and Figure 2 is an enlarged view of the particles of highly dispersed acrylic resin ultrafine particles and alumina powder used in Figure 1. An explanatory diagram, Figure 3 is an explanatory diagram of the case where corrosion-resistant particles are attached to a mold, and Figure 4 is an explanatory diagram of a case in which a casting resin insulating base material is poured using a mold having the corrosion-resistant particles attached in Figure 3. Fig. 5 is an enlarged sectional view of the surface of the insulator after casting according to Fig. 4, Fig. 6 is a diagram showing the erosion characteristics of the corrosion-resistant layer, and Fig. 7 is an explanatory diagram of the insulator used in general. FIG. 8 is a side view of a 10 kV insulator, which is a conventional insulator. 10... Insulator, 11... Cast resin edge base material, 12.
... Uneven portion, 13... Metal fitting, 14... Highly dispersible acrylic resin ultrafine particles, 15... Alumina powder, 16...
・Corrosion-resistant layer, 17...Mold, 18...Spray gun,
23...Glass fiber, 24...Alumina powder. Applicant's agent Sato - 3rd map also 4th map horse 5th map Fn ding food j4 F+4; lPm)

Claims (1)

[Scope of Claims] 1. A resin molded part for high voltage insulation, characterized in that corrosion-resistant particles having fine resin particles dispersed thereon are applied to the surface of a cast resin insulation base material. 2. Corrosion-resistant particles with resin fine particles dispersed on the surface are attached to the inner surface of a high-temperature mold, a casting resin insulating base material is injected into this mold, and the corrosion-resistant particles are applied to the surface of the casting resin insulating base material. A method for manufacturing resin molded parts for high voltage insulation, characterized by adhering the parts.