JPH08205373A - Conductor connection for solid insulated power cable - Google Patents

Abstract

PURPOSE: To avoid the shrink-back of a cable insulating body by placing O-rings between the cable insulating bodies and extended portions of compressed sleeve for conductor connection thereby forming oil-tight seals at the interface of the cable insulating body. CONSTITUTION: A compressed sleeve 3 for conductor connection comprises a compressed portion 31 located on a cable conductor 1 and a thin-walled extended portion 32 extending in the length direction at both the sides of the compressed portion 31. There is a groove 32a for fitting the O-ring 4 on the inner surface of the extended portion 32, O-ring 4 is attached to this groove 32a, and the O-ring 4 is pressed by compressing and connecting the cable conductor 1 by compressing the compressed portion 31. By doing this, the oil-tight seal can be formed at the interface of the cable insulating body 2, and the shrink-back of the cable insulating body 2 can be avoided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductor connecting portion in an intermediate connecting portion of a power cable having a solid insulator such as crosslinked polyethylene formed by extrusion.

[0002]

BACKGROUND OF THE INVENTION Conventionally, solid insulated power cables such as CVs.
At the oil-immersion type terminal connection of the cable (cross-linked polyethylene insulated power cable), wrap polyethylene tape, etc. from the cable conductor to the end of the cable insulator to prevent the insulating oil in the terminal connection box from flowing out to the cable conductor side. After turning, the cable conductor and the cable insulator are integrally molded by heating.

On the other hand, by shortening the construction period of the intermediate connecting portion of a solid insulated power cable such as a CV cable, the reinforcing insulating layer of the connecting portion is used as an economical and compact electrically stable intermediate connecting portion. A new structure has been proposed that is composed of an oil-immersed insulating tape winding layer. FIG. 2 is a vertical cross-sectional view of the upper half of an example of such an intermediate connecting portion.
As shown in the drawing, an insulator block 11 containing an internal shield 12 is arranged on a conductor connecting portion 3 in which a cable conductor 1 is compression-connected by a compression sleeve.
A tape winding insulating layer 13 formed by winding a thin insulating tape is provided on both sides and outside, and insulating oil 16 is filled in an outer case 15 provided on the outside thereof. In the drawing, 14 is a shielding layer on the tape winding insulating layer 13.

[0004]

In the intermediate connecting portion as shown in FIG. 2, there is a problem that insulating oil flows out to the cable conductor side from the interface between the cable insulator and the insulator block. In order to prevent such outflow of insulating oil, it is conceivable to wind polyethylene tape or the like and then heat it to integrally mold it. However, it requires a lot of equipment such as a temperature control device and a pressurizing device, and it takes 2 to 3 days to form one shield part. Further, it is necessary to strictly control heating and pressurization so as not to adversely affect the electric performance of the cable, and it cannot be said that it is appropriate for field work.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and provides a conductor connecting portion of a solid insulated power cable which enables a seal portion to be easily formed at the time of conductor connecting without heat treatment. The present invention is characterized in that a compression sleeve for connecting a conductor comprises a compression portion located on a cable conductor and extensions extending on both sides thereof and located on ends of a cable insulator. This is because an O-ring was interposed between the cable insulators.

[0006]

In the conductor connecting portion of the present invention, by using the compression sleeve having the above-mentioned structure, the O-ring interposed between the extension portion of the compression sleeve and the cable insulator at the same time when the conductor is compression-connected, the interface is formed. The oil-tight sealing of Also, this O-ring allows maximum cable insulation.
With a structure that can withstand a shrink back of 30 mm (currently the maximum is 20 to 25 mm), it is possible to reduce the shrink back of the cable insulator.

[0007]

1 is a vertical cross-sectional view of the upper half of an essential part of a concrete example of a conductor connecting portion of the present invention. In the drawing, 1 is a cable conductor, 2 is a cable insulator formed by extrusion of cross-linked polyethylene, etc., and its end portion is preliminarily stepped off according to the inner diameter of the O-ring 4, and its outer peripheral surface is mirror-finished. ing. Reference numeral 3 denotes a compression sleeve for connecting a conductor, which includes a compression portion 31 located on the cable conductor 1 and thin extension portions 32 extending in the length direction on both sides thereof. A groove 32a for fitting the O-ring 4 is provided on the inner surface of the extension portion 31, and the O-ring 4 is mounted in this portion. By compressing the compression portion 31 and connecting the cable conductor 1 by compression, The O-ring 4 is pressed to form an oil-tight seal at the interface of the cable insulator 2 and prevents the cable insulator 2 from shrinking back.

[0008]

As described above, according to the conductor connecting portion of the solid insulated power cable of the present invention, the oil-tight sealing can be performed simultaneously with the compression connection of the conductor without performing heat treatment. It does not require a lot of equipment and can significantly shorten the construction period. In addition, it also has an effect of reducing shrink back of the cable insulator. Therefore, C
It is extremely effective when used for forming an intermediate connection portion of a solid insulated power cable such as a V cable.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of an upper half of a main part of a specific example of a conductor connecting portion of the present invention.

FIG. 2 is a vertical cross-sectional view of an upper half of an example of an intermediate connection portion of a solid insulated power cable.

[Explanation of symbols]

 1 cable conductor 2 cable insulator 3 compression sleeve 31 compression part 32 extension part 4 O-ring

Claims (1)

[Claims] 1. A compression sleeve for connecting a conductor comprises a compression portion located on the cable conductor and extension portions extending on both sides of the compression portion and located on ends of the cable insulator. A conductor connecting portion of a solid insulated power cable, characterized in that an O-ring is interposed therebetween.