RU2372681C1 - Support composite insulator - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: insulator consists of hollow insulating body (1) arranged in the form of cone, cylinder, with central rod (5), having threaded hole (6) for fastening bolt (7). Thread is made only on upper part of rod (5) at the height of at least 0.5 of insulator construction height. Along full height of insulator body (1) internal cavity from lower part (2) to upper part (3), stiffening ribs (8) are arranged. Projecting beads may be made on stiffening ribs (8) for additional fixation of insulator to bearing structures. Internal cavity of body (1) may be filled with foaming material of low density, protective ribbed shell (11) is molded from organosilicic composition on external side surface of body, and at the bottom insulator is closed with cover in cases when insulator operates under extremely contaminated and moisturised conditions.

EFFECT: low material intensity, good strength characteristics, simple technological manufacturing process.

10 cl, 3 dwg

Description

The invention relates to the fields of electrical engineering and the electric power industry, for example, to reference composite (polymer) insulators for high-voltage substations and overhead power lines.

Known reference polymer insulator containing the end parts with metal reinforcement, interconnected by an insulating body, while the metal reinforcement is made in the form of fasteners mounted on the end parts of the insulator, the perimeter of each of which is made of insulating protrusions [1].

However, this reference polymer insulator has significant disadvantages:

- high consumption of materials on the insulating casing (the casing is made in the form of a continuous insulating body) to provide the necessary strength of the insulator under the action of bending loads, as well as torsion, compression and tensile loads;

- all types of acting mechanical loads are applied to the end sections of the insulating casing, and, therefore, the strength of the insulator will be largely determined by the strength of the seal of the metal reinforcement. For example, the bending moment acting on the insulator is actually determined by the bending force, and the shoulder of its impact is almost equal to the construction height of the insulator. As a result, when exposed to bending loads, the outer side of the insulator body (opposite to the direction of action of the bending force) will work in tension, and the inner, respectively, in compression. Under these conditions, the achievement of the required bending strength of the insulator is ensured, as a rule, due to the large cross-sectional area of the housing (body of revolution), which ultimately leads to an increase in the mass (weight) of the insulator.

A support insulator is also known, comprising a hollow body made of insulating material with partitions separating the internal cavity into three compartments, metal flanges installed at the ends of the body, and extreme compartments filled with expanding polymerization insulating foam sealant, for example silpen [2].

In this insulator, an attempt was made to reduce the mass (weight) by replacing a solid (monolithic) body with a hollow cylinder while maintaining its strength characteristics. However, this goal has not been fully achieved, since the metal flanges remain in the insulator, which make up the bulk of the insulator and require the installation of insulating partitions and filling cavities with foam sealants to ensure the tightness of the insulator, which complicates the design of the insulator and its manufacturing technology.

The applicant solved the problem of developing a support composite (polymer) insulator with a small mass, but with high strength electrical characteristics, which reduces material consumption, labor intensity in manufacturing and improves the reliability of the insulator in adverse atmospheric conditions due to the rejection of metal flanges, replacement of solid (monolithic) bodies and pipe structures with partitions and fillers on hollow structures with vertical stiffeners and transfer of the attachment point from the radiator from its lower part to the upper. The set of essential structural features of the proposed support composite insulator, providing the above-mentioned positive technical result, is given in the following claims: “support insulator made in the form of a spatial structure of an insulating cast composite material containing a hollow body in the form of a geometric figure with an open lower part and a thickened upper a part having at least one threaded hole for mounting current-carrying elements, central th rod with an internal longitudinal hole with a thread for a mounting bolt made in the upper part of the hole of the rod at a height of at least 0.5 of the insulator's building height, while at least four oriented radially vertical stiffeners are made between the central rod and the body, extending along the entire height insulator from its base to the upper thickened part; the body is made in the form of a hollow truncated cone; the body is made in the form of a hollow cylinder; the body is made in the form of a hollow geometric figure with an oval in cross section having constant dimensions along the height of the insulator; the body is made in the form of a hollow geometric figure with an oval in cross section having variable dimensions along the height of the insulator; a glass-filled polyamide was selected as an insulating casting composite material of the body; on the outer side surface of the housing through vulcanization molded protective ribbed sheath of an organosilicon composition; the internal cavity of the housing is closed from below by a lid of an organosilicon composition; the internal cavity of the body is filled with insulating foaming material of low density; at least one stiffener has in the lower part protrusions-thickenings with threaded holes for additional fastening of the insulator to the supporting structure. "

The invention is illustrated by drawings, where figure 1 shows a main view with a cut along the vertical plane of the supporting composite insulator made according to the present invention; figure 2 is a view along arrow a in figure 1; figure 3 is a view along arrow B in figure 1.

The inventive support composite (polymer) insulator is a spatial structure cast from an insulating cast composite material, for example, glass-filled polyamide. It is made in the form of a hollow body 1, made, for example, in the form of a truncated cone, cylinder or in the form of a hollow geometric figure with an oval in cross section having constant or variable dimensions along the height of the insulator. The lower part 2 of the housing 1 is open, and the upper thickened part 3 has threaded holes 4, designed to provide fastening of current-carrying elements connected to the insulator (not shown). In the inner cavity of the housing 1 of the insulator passes a central rod 5 with an internal longitudinal threaded hole 6 for the mounting bolt 7. The thread is performed in the upper part 3 of the rod 6 at a height of not less than 0.5 of the building height of the insulator.

Between the central rod 6 and the housing 1, vertical stiffening ribs 8 are made, oriented radially, extending to the entire height of the insulator from its lower part 2 to the upper part 3 and forming a cross-shaped (star-shaped) figure in the cross section of the insulator, respectively, provided that their number not less than four. On the ribs 8 can be provided with vertical protrusions-thickenings 9 having threaded holes 10, which are intended for additional fastening of the insulator to the supporting structures. In order to prevent contamination and humidification of the insulator, the inner space between the central shaft 5 and the inner surface of the housing 1 may be filled with low-density insulating foam-forming material. On the outer side surface of the housing 1 by means of vulcanization can also be molded protective ribbed shell 11 of an organosilicon (silicone) composition. From below, the insulator housing 1 can be closed with a cover (not shown) also to prevent contamination and wetting the inner surface of the housing 1.

The invention works as follows.

The mechanical loads acting on the insulator are perceived by the insulating body (body 1) of the insulator, which is a hollow truncated cone (or cylinder), closed at the top and reinforced by vertical stiffeners 8 and the central rod 5. When the compressive and tensile forces act, the strength of the insulating body 1 is determined by the area its cross section and material strength. But for supporting insulators the determining factor is their ability to withstand bending moments, and the moment of inertia of the insulating body depends not only on its cross-sectional area, but also on the configuration of the insulating body. It is known that the annular cross section of the body has a moment of inertia several times larger than the moment of a circle with their same area. The installation of vertical stiffeners 8 greatly increases the moment and efficiency of use of the material. The bending moment is determined by the amount of force applied to the upper part 3 of the insulator housing 1 and the distance (shoulder) from the point of application of force to the attachment point, therefore, transferring the attachment point to a height of at least 0.5 of the insulator's building height reduces the acting load. The Central mounting bolt 7 creates a preliminary compression stress in the housing 1 and stiffening ribs 8 of the insulator, contributing to an increase in its stability under the influence of tensile forces arising on the external (relative to the direction of action of the force) part of the insulator. An additional fastening of the insulator, carried out by screws in the threaded holes 10 of the protrusions-bulges 9 stiffeners 8, is provided only for insulators exposed to torques.

The manufacture of the insulator is carried out by injection molding on automatic molding machines in one step and does not require assembly operations, with the exception of vulcanization of the protective shell 11 for insulators designed for use in outdoor conditions with contamination and moisture.

The introduction of the proposed insulators into the practice of electric grid construction will allow us to provide significant savings in material and production costs while preserving their strength and operational characteristics.

Information sources

1. Description of the invention to the patent of the Russian Federation “Support polymer insulator” No. 2130660, class H01B 17/14, 17/02, priority July 26, 1996, published May 20, 1999. Bulletin No. 14.

2. Description of the invention to the copyright certificate “Support insulator” No. 819824, class H01B 17/14, priority 03.04.79, published 04/07/81, Bulletin No. 13.

Claims (10)

1. The support insulator, made in the form of a spatial structure of an insulating injection molded composite material, comprising a hollow body with an open lower part and an upper thickened part having at least one threaded hole for fastening current-carrying elements, a central rod with an internal longitudinal hole with a thread for a mounting bolt made in the upper part of the hole of the rod at a height of at least 0.5 of the building height of the insulator, while at least even between the central rod and the body PEX radially oriented vertical ribs extending across the height of the insulator from the base to the upper thicker portion. 2. The insulator according to claim 1, in which the housing is made in the form of a hollow truncated cone. 3. The insulator according to claim 1, in which the housing is made in the form of a cylinder. 4. The insulator according to claim 1, in which the housing is made with an oval in cross section having constant dimensions along the height of the insulator. 5. The insulator according to claim 1, in which the housing is made with an oval in cross section having variable dimensions along the height of the insulator. 6. The insulator according to claim 1, in which a glass-filled polyamide is selected as the insulating molding composite material of the housing. 7. The insulator according to claim 1, in which on the outer side surface of the housing by vulcanization molded protective ribbed shell of an organosilicon composition. 8. The insulator according to claim 1, in which the inner cavity of the housing is closed from below by a lid of an organosilicon composition. 9. The insulator according to claim 1, in which the internal cavity of the housing is filled with insulating foaming material of low density. 10. The insulator according to claim 1, in which at least one stiffener has in the lower part protrusions-thickenings with threaded holes for additional fastening of the insulator to the supporting structure.

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