JP2509852B2 - Resin molded insulator - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a resin insulation molding used for supporting a high-voltage conductor.

[0002]

2. Description of the Related Art Conventionally, porcelain has been traditionally used for porcelain insulators, insulators, etc. used to support high-voltage conductors, but it is heavy, fragile, and not easy to manufacture. Therefore, casting products of curable resins, especially epoxy resins, are often used.

In the curable resin used for such casting, an inorganic filler such as alumina is used in order to reduce curing shrinkage, curing heat generation, thermal shock resistance, hardness and abrasion resistance. , Silica, etc. are added.

In the casting of a curable resin, the mold heating time for curing is shortened to improve the manufacturing efficiency, and when the resin is cured and shrunk, the mold resin injection port near the mold resin injection port which is not yet cured is used. In order to prevent the sink mark by flowing the molten resin smoothly toward the contracted part, the resin is heated and melted at a temperature as high as possible (a little lower than the curing temperature), and this molten resin is placed in the mold. Injecting. Therefore, after the molten resin is injected into the mold, the filler continues to settle and the filler segregation occurs until the viscosity of the resin liquid reaches a certain level due to the progress of curing of the resin, and the resin latch portion is formed on the upper side of the mold. , A filler-rich portion is generated on the lower side of the mold.

If the curing speed is increased in order to reduce the filler segregation, the sink marks caused by the curing shrinkage become remarkable, and the quality deterioration of the dimensional accuracy of the product becomes a problem. Therefore, when the insulating molded body is cast by the filler-containing epoxy resin, it is inevitable that the filler-rich portion and the resin-rich portion are generated due to the filler segregation.

[0006]

By the way, the insulating molded body used for supporting the high-voltage conductor is in a stress state due to a load during use, but the stress state varies depending on the load condition and a uniform stress is applied. In the case of distribution, it is rare, and it is usual that tensile stress acts strongly on one part and compressive stress acts strongly on another part.

On the other hand, the mechanical characteristics of the above-mentioned filler-rich structure and resin-rich structure differ depending on the type of filler, the compatibility of the filler with the resin, etc. The filler-rich structure is stronger in compression than the resin-rich structure, and the resin-rich structure is stronger in tension than the filler-rich structure.

As described above, in the cast insulation molded body, since the filler-rich portion which is strong against compression and the resin-rich portion which is strong against tension are present, the filler is located at the portion where the compressive stress is strong in the stress distribution during use. -It is effective to position the rich portion in the resin rich portion at a position where the tensile stress of the same stress distribution is strong.

However, it is difficult for the naked eye to discriminate between the filler-rich portion and the resin-rich portion, and in the conventional casting resin insulator, the filler is applied to a portion where the compressive stress is strong in the stress distribution at the time of use. It is not easy to locate the resin rich portion in the rich portion where the tensile stress of the same stress distribution is strong.

The object of the present invention is to easily know the filler-rich portion and the resin-rich portion which are difficult to distinguish with the naked eye, which occur when an insulator is cast with a curable resin containing a filler and can be easily used. The object is to provide a resin insulation molded body that can be used in an orientation suitable for the stress distribution state.

[0011]

The resin molding of the present invention is
The resin composition is cast with a filler-containing resin composition, has a resin injection mark on the outermost periphery, and the resin injection port mark is processed so as to be distinguishable.

[0012]

Function: The position of the resin injection port in the product can be known, and therefore, the arrangement state of the mold at the time of casting can be known. Therefore, the filler-rich portion and the resin-rich portion can be known by knowing the sinking direction of the filler. Can be recognized.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1A is a sectional view of an embodiment of the present invention, and FIG. 1B is a front view of the same. An insulating spacer used for supporting a connecting conductor in a GIS (gas insulation breaker) is shown. Shows. In FIG. 1A and FIG. 1B, reference numeral 1 denotes a filler-blended epoxy resin molding, which has a relatively shallow conical cylinder portion 11 and a flat peripheral edge portion 12 having a circular outer periphery. 21 is a conductor connection fitting embedded in the molded body 2
Reference numeral 2 denotes a bolt insertion fitting that is embedded in the outer peripheral portion of the molded body 1 at a predetermined interval in the circumferential direction. Reference numeral 3 is a resin injection port mark, which is present on the outermost circumference of the molded body and is cut by a flat cut end so that the resin liquid injection position can be identified within a limit that does not hinder the use of the insulating spacer.

FIG. 2 shows a state of the above-mentioned insulating spacer at the time of casting. In the vertical mold 4 in which the conductor connection fitting 21, the bolt insertion fitting 22 and the like are set, the resin liquid is poured directly above the mold. Entrance 4
From 1 (the resin liquid injection port is provided on the top of the mold for degassing and minimizing the resin loss in the resin liquid injection pipe), a molten epoxy resin containing a filler is injected, The resin surface at the pouring port is being pressurized by gas pressure to cure it.

In the initial stage of this curing, the filler continues to settle, the curing of the resin progresses, and until the viscosity of the resin reaches a viscosity that does not allow the filler to settle, the sedimentation continues and the bottom surface of the mold 4 continues. Above the upper half peripheral surface of the conductor connecting fitting 21 and immediately above the upper half peripheral surface of the bolt insertion fitting 22, a filler is formed to form a filler-rich portion. With the formation of the filler-rich portion, inside the mold 4. Upper side, conductor connection fitting 21
A resin rich portion is formed just below the lower half peripheral surface of the bolt and immediately below the lower half peripheral surface of the bolt insertion fitting 22 (the filler rich portion means about 1.0 of the average content% of the filler in the molded body).
About 5 to 1.3 times, and the resin rich part is
It means about 0.85-0.95 times the average%).

The position where the filler-rich portion is formed is the same as the product (insulation spacer) shown in the above figure when the product is pointed in the direction of the angle with the processed resin injection port trace 3 as the uppermost position. And the bottom of the conductor, the upper half of the conductor connection fitting 21, the upper half of the bolt insertion fitting 22, and the like, which can be easily recognized. Also, the position of the resin rich portion can be easily recognized from the relative positional relationship between the filler rich portion and the position of the filler rich portion.

The stress distribution of the above-mentioned insulating spacer in use is complicated, but the load of the connecting conductor causes compression below the connecting conductor and pulling above the connecting conductor. If the resin injection mark of is located at the uppermost position and the filler-rich portion that is strong against compression is located on the lower half side of the connecting conductor, and the resin-rich portion that is resistant to tension is located on the upper half side of the connecting conductor, The portion and the resin-rich portion can be advantageously used in terms of mechanical properties.

FIG. 3A is a side view showing a part of an insulator of another embodiment of the present invention in cross section, and FIG. 3B is the same as FIG.
The cross section of (a) is shown. .
In FIG. 3A and FIG. 3B, reference numeral 1 is a filler-mixed epoxy resin molded body, which has the shape of a drum. Reference numerals 2 and 2 denote fixing metal fittings embedded in both ends of the molded body. Reference numeral 3 denotes a resin injection port mark, which exists on the outermost circumference of the molded body, and is cut by a flat cut end so that the resin liquid injection position can be identified to the extent that it does not hinder the use of the insulating spacer.

FIG. 4 shows the state of the above-mentioned insulator during casting. In the horizontal mold 4 in which the fixing metal fittings 2 and 2 are set, the filler mixture is melted from the resin liquid injection port 41 directly above the mold. Epoxy resin is injected, and the liquid surface of the resin at the injection port is pressurized by gas pressure to cure the resin. At the time of this curing, a filler-rich portion is formed on the upper half circumference of each fixing metal fitting 2 and on the bottom surface in the mold 4, and a resin rich portion is formed just below the lower half circumference of each fixing metal fitting 2 and on the upper side of the mold 4. To generate.

Although this insulator has different load conditions depending on usage conditions, when it is used under the action of a bending moment as shown by an arrow M in FIG. The stress acting on the interface with and becomes a tensile stress, and the stress acting on the interface between the lower half of each fixing metal fitting and the resin becomes a compressive stress.

Therefore, the filler-rich portion and the resin-rich portion around each fixing member are recognized from the cutting position of the resin injection port mark of the insulator, and the filler-rich portion is set as the compression stress side and the resin-rich portion is set as the tensile stress side. If the insulator is used in such an orientation, it can be advantageously used for the mechanical properties of the filler-rich portion and the resin-rich portion.

[0022]

The resin insulation molding of the present invention has the above-described structure and is molded by the casting method, but the resin injection port trace is processed so that the position of the injection port trace can be recognized. The position of the filler-rich portion and the resin-rich portion due to the segregation of the filler can be recognized by knowing the direction of the mold during casting from the appearance of the product, and the filler depending on the stress distribution when the resin insulator is used. The filler segregation can be effectively utilized in terms of strength by locating the rich portion at a location having a strong compressive stress or the resin rich portion at a location having a strong tensile stress.

[Brief description of drawings]

FIG. 1A is a sectional view showing an embodiment of the present invention, and FIG. 1B is a front view of the same.

FIG. 2 is a cross-sectional view showing a casting state of the above embodiment.

3 (A) is a side view partially showing a cross section of another embodiment of the present invention, and FIG. 3 (B) is a cross-sectional view taken along line (A) of FIG.

FIG. 4 is a cross-sectional view showing a casting state of the another embodiment.

[Explanation of symbols]

 3 Resin injection port mark

Claims (1)

(57) [Claims] 1. A resin-molded insulator, which is cast with a filler-containing resin composition and has a resin injection mark on the outermost periphery, and the resin injection port mark is processed in a distinguishable manner.