RU2568666C1 - Manufacturing method for elastomeric unit intended to balance electric field for cable coupling sleeve - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: method includes moulding of electrode (1), its mounting at an embedded part (3) to the matrix (5) so that openings (4) in the embedded part (3) are placed under the electrode (1), injecting into the matrix (5) of moulding shell (2) represented by liquid insulating silicone rubber, at that the electrode (1) is pressed to surface of the embedded part (3) by vacuum pumping in its inner cavity by means of a suction pump.

EFFECT: improved contact of current-conductive element of the moulded elastomeric unit of the cable coupling sleeve with conductive surface of pigtail.

1 dwg

Description

Technical field

The invention relates to a technology for manufacturing cable fittings of high-voltage cables with XLPE insulation and can be used in the manufacture of elastomeric units for aligning the electric field for cable terminations and connectors.

State of the art

In power cable terminations and couplings with cross-linked polyethylene insulation, elastomeric electric field alignment units are used, consisting of a cone electrode molded from conductive silicone rubber intended to contact the cable conductive surface at the point of its cutting, and a sheath cast from insulating silicone rubber [RU 2190913].

When using such an elastomeric assembly made in a known manner, the contact surface of the electrode is not tightly attached to the cable and often has streaks of insulating silicone rubber.

A known method of casting metal parts, according to which the porosity in the cast parts is eliminated by prepress castings [RU 2142354]. This method of eliminating unwanted air inclusions unnecessarily complicates the design of the mold and is ineffective in the case of casting parts from silicone elastomers.

A known method of manufacturing an elastomeric site from several silicone elastomers by casting using a split mold [RU 2143147]. According to this method, to eliminate air impurities, the viscosity of the silicone elastomer is increased by preliminary shear deformation of its composition.

The application of this method also does not allow to reliably eliminate the indicated causes of loose contact of the conductive elastomeric element with the conductive surface of the cut cable.

Disclosure of invention

The technical result of the invention is improving the contact of the conductive element of the molded elastomeric node of the cable sleeve with the conductive surface of the cut cable.

The subject of the invention is a method of manufacturing an elastomeric unit for aligning the electric field for a cable sleeve, characterized in that the electrode is molded from conductive silicone rubber, a cast electrode placed on the embedded part is installed in the matrix forming its insulating sheath, and liquid silicone insulating is injected into said matrix rubber, using a embedded part having an internal cavity with through holes under the electrode, and pressing the electrode to the surface embedded parts by evacuating its internal cavity.

This allows you to get the above technical result.

The implementation of the invention

The figure illustrating the implementation of the method shows two elements of an elastomeric unit for aligning the electric field: an electrode 1 and an insulating shell 2, as well as components of an injection mold, a hollow embedded part 3 having an internal cavity with holes 4, and a matrix 5 forming a shell 2.

First, an electrode 1 (usually having a conical shape) is cast from a liquid conductive rubber, using the appropriate matrix and embedded part for this.

Then use the mold from the matrix 5 and the embedded part 3. The cast electrode 1 is installed on the embedded part 3 of it in the matrix 5 so that the holes 4 are located under the electrode 1, and liquid insulating silicone rubber is injected into the matrix 5. In this case, the electrode 1 is pressed to the surface of the embedded part 3 by evacuating its internal cavity using a suction pump.

This provides a more tight fixation of the electrode 1 on the surface of the embedded part 3, avoids the displacement of the electrode 1 during the injection of liquid silicone rubber and its vulcanization in the matrix 5 and to prevent the liquid insulating rubber from flowing under the electrode 1.

After the elastomeric assembly made in this way is mounted on the conductive surface of the cut cable, its tight contact with the electrode 1 is provided, which is necessary for high-quality equalization of the electric field strength in the high-voltage cable sleeve.

Claims (1)

A method of manufacturing an elastomeric unit for aligning the electric field for a cable sleeve, characterized in that the electrode is molded from conductive silicone rubber, a cast electrode placed on the embedded part is installed in the matrix forming its insulating shell, and liquid insulating silicone rubber is injected into said matrix, this uses a embedded part having an internal cavity with through holes under the electrode, and presses the electrode to the surface of the embedded part by vacuum tion of its internal cavity.