JPH11273465A - Rubber or plastic insulated power cable of water-cooled pipe type - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new power cable which can be laid as substitute in a steel pipe of a POF cable (pipe type OF cable) upon removing the cable and insulating oil from the steel pipe, whereby such a conventional problem is solved, that oil leakage is generated at an existing POF cable in association with corrosion of its steel pipe to lead to an environmental problem and increase in maintenance costs. SOLUTION: A cable insulated with rubber or plastics to be laid as substitute in an existing POF cable steel pipe is structured so that a lead covering 5 is provided on the external semiconductive layer 4 of a cable core, whereon a metal tape 6 of stainless steel, etc., is wound, and a skid wire 7 is wound spirally on the winding layer of the metal tape 6, and therein water is fed by pressure or circulated in the steel pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an existing pipe type O
The present invention relates to a rubber or plastic insulated power cable which is effective as a replacement for an F cable or a pipe type gas filled cable. In particular, the present invention relates to a rubber or plastic insulated power cable that enables a transmission capacity equal to or greater than that of a pipe-type OF cable having a large transmission capacity.

[0002]

2. Description of the Related Art Pipe type OF cables (hereinafter referred to as POF)
The cable has a structure shown in the sectional view of FIG. That is, the unit cable 100 is drawn into the steel pipe 8 already laid, and the steel pipe 8 is filled with the insulating oil 45 to be configured. The unit cable 100 includes the conductor 41
Is provided with an insulating layer 42 mainly made of kraft paper or semi-synthetic paper impregnated with insulating oil, and a reinforcing and moisture-proof layer 43, on which a skid wire 44 is wound to form a unit cable. Is drawn into the steel pipe 8.

[0003]

By the way, the existing POF
Cables are subject to oil leakage due to corrosion of steel pipes, etc., and are problematic in terms of environmental problems and increased maintenance costs. For POF cables in which oil leaks due to the corrosion of the steel pipe, the insulating oil and the inner cable are removed and the conventional CF
Although a method of drawing in a V cable or the like can be considered, the following problem occurs.

[0004] Compared to the transmission capacity of existing POF cables, the transmission capacity of rubber or plastic insulated cables that can be pulled into the same steel pipe is very small, and construction of a new line is required in parallel to achieve the same transmission capacity. Required. In such a method, the cost is higher than the new construction cost without using the existing POF cable.

Furthermore, when a conventional cable with an anticorrosion layer is drawn into a steel pipe, friction with the steel pipe becomes large, so that the existing POF cable cannot be extended with the length between the joint manholes, and the number of manholes needs to be greatly increased. And construction costs increase.

It is an object of the present invention to provide a new water-cooled pipe-type rubber or plastic insulated power cable that solves the above-mentioned problems.

[0007]

In order to achieve the above object, according to the present invention, there is provided a rubber or plastic insulated cable replaced with an existing pipe type OF cable steel pipe or pipe type gas-filled cable steel pipe. In this cable structure, a lead coating is applied on the outer semiconductive layer or the semiconductive shielding tape winding layer of the cable core, a metal tape is wound thereon, and a skid wire is spirally wound on the metal tape winding layer. It is characterized in that water is injected into the steel pipe or cooling water is circulated in the steel pipe.

Since the water-cooled pipe-type rubber or plastic insulated power cable of the present invention has the above-described structure, the lead sheath on the outer semiconductive layer of the cable core or the winding layer of the semiconductive shielding tape acts as a water shielding layer. I do. The wound layer of metal tape such as stainless steel on the lead cover acts to mechanically reinforce the lead cover. Further, the skid wire spirally wound on the metal tape winding layer acts to reduce a frictional force generated between the steel pipe and the cable when the cable is pulled in.
Furthermore, power transmission capacity is increased by press-fitting or circulating water between the steel pipe and the cable.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view illustrating a configuration of a unit cable 10 of the cable of the present invention which is exchanged and housed in a steel pipe 8 of an existing POF cable shown in FIG. In the drawing, a unit cable 10 is provided with an inner semiconductive layer 2, an XLPE insulating layer 3 and an outer semiconductive layer 4 around a conductor 1 by simultaneous extrusion of three layers (two layers of an inner semiconductive layer and an insulating layer). Only in some cases.)
And a stainless steel tape is wound thereon to form a stainless tape winding layer 6, on which a stainless steel skid wire 7 is spirally wound.

A semiconductive shielding tape winding layer used depending on required functions such as a cushion layer, a water shielding layer, a copper wire woven semiconductive tape winding layer, or the like may be provided on the outer semiconductive layer 4. .

The stainless steel tape and the stainless steel skid wire may be a metal tape and a skid wire of another non-magnetic material (such as an aluminum alloy or a copper alloy).

The three unit cables 10 are connected to the insulating oil 45 of the existing POF cable shown in FIG.
0 is removed and housed in the steel pipe 8 after removal.

After being housed in the steel pipe 8, the steel pipe 8
Water 9 is press-fitted or circulated between cable 10 and cable 10.

FIG. 3 shows a conventional CV cable structure in which an inner semiconductive layer 2, an XLPE insulating layer 3, an outer semiconductive layer 4, a shielding tape layer and a shielding copper tape 3 are provided around a conductor 1.
5, a binder tape 36 and a vinyl sheath 37 are sequentially provided.

In the above embodiment, the unit cable 10 has an insulating layer of cross-linked polyethylene (XLPE) insulation. However, a unit cable of rubber insulation may be used.

Further, the steel pipe 8 has been described with respect to the steel pipe of the existing POF cable.
F) It may be a steel pipe of a cable.

[0017]

According to the water-cooled pipe-type rubber or plastic insulated power cable of the present invention described above, the following effects can be obtained.

(1) Complete water shielding is possible by applying a lead coating to the cable insulator.

(2) Since the anticorrosion layer is not provided on the cable shielding layer, the heat resistance can be reduced, so that water cooling works effectively and the power transmission capacity can be increased.

(3) Since a skid wire is wound in place of the anticorrosion layer, it is possible to extend a wire having a long span equivalent to that of a POF cable.

(4) The lead coating is chemically very stable even when directly cooled with water, and can be used for a long time.

(5) Since water is used for cooling, water leakage caused by corrosion of the steel pipe does not pose a problem of environmental pollution.

(6) Since existing facilities are effectively used, construction costs are low.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a unit cable example of a water-cooled pipe-type rubber or plastic insulated power cable of the present invention.

FIG. 2 shows a cross section of a water-cooled pipe-type rubber or plastic insulated power cable of the present invention.

FIG. 3 is a perspective view showing a configuration of a conventional CV cable.

FIG. 4 shows a cross section of a POF cable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cable conductor 2 Inner semiconductive layer 3 XLPE insulator 4 Outer semiconductive layer 5 Lead coating 6 Stainless tape 7 Skid wire 8 Steel pipe 9 Water 35 Copper tape 37 Vinyl sheath 45 Insulating oil

Claims (1)

[Claims] 1. A rubber or plastic insulated cable replaced in an existing pipe-type OF cable steel pipe or pipe-type gas-filled cable steel pipe, wherein the cable structure comprises a cable core outer semiconductive layer or semiconductive shielding tape. Lead coating is applied on the wound layer, a metal tape is wound thereon, and a skid wire is spirally wound on the metal tape wound layer. And a water-cooled pipe-type rubber or plastic insulated power cable.