JPS6168807A - Ant preventive wire and cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to electric wires and cables provided with termite resistance.

[Conventional technology] Electrical wires and cables for control, power, communication, etc., which are installed underground or underground in areas where termites are inhabited, are damaged by termites, and energy and information transmission is damaged by termites. An accident has occurred that causes major problems.

As a measure against such accidents, termite-proof electric wire cables having a structure in which nylon 8 is provided in the outermost sheath of electric wires and cables have recently been put into practical use.

Nylon's termite-proofing properties are said to be more due to its physical hardness than its chemical composition, and in fact, rigid plastics such as epoxy, polycarbonate, and polyacetal have been proven to have excellent termite-proofing properties.

As described above, nylon has reliable termite-proofing properties, and this nylon is applied as the outermost sheath of electric wires and cables by extrusion or tape wrapping.

On the other hand, for underground or conduit wires and cables, including these termite-proof wires and cables, damage, trauma, deterioration, deterioration, etc. of the wires and cables may occur after the installation work or during actual use. In order to confirm the integrity of the cable, such as whether or not the cable is damaged, withstand voltage tests and absolute J-bag resistance tests are increasingly being conducted not only on the insulator but also on the sheath.

Among these, it is particularly necessary to measure the insulation resistance characteristics of the sheath Ell during lightning resistance by providing appropriate electrodes inside and outside the sheath. The electrodes inside the sheath can generally utilize the total flexure 5 as the external shielding layer of the cable, but the external electrodes outside the sheath (metal tape or metal braided blades can be considered as the field), Providing electrodes poses problems not only economically, but also in terms of ease of handling and installation work. Until now, with vinyl or polyethylene sheaths, conductive paint was applied to the surface, or conductive compound was extruded and coated. methods have been taken.

``Problem that the invention seeks to solve
However, compounds or paints that can be used as external electric bodies have not yet been developed or put into practical use, and the problem is that it is not possible to measure the withstand voltage or insulation resistance of anti-gA wires and cable sheaths equipped with nylon sheaths. .

In particular, in electric wires and cables that use high-density polyethylene as a sheath and press a nylon termite-proof layer on top of the sheath, there is some concern that high-density polyethylene may crack due to heat or environmental stress, so it is difficult to understand the soundness of such sheaths. This is extremely important and an electrode material suitable for nylon is desired.

The present invention is based on the above, and the present invention uses glue Lll as an external electrode that enables the sheath of a V-shaped dovetail wire/cable having a nylon sheath to be fixed at the rJ4 tortoise pressure (or the insulation U). The purpose of the present invention is to provide a novel V1-proof electric wire/cable provided with a conductive layer.

[Means for Solving the Problems] The electric wire/cable of the present invention is provided with a nylon layer on the outer periphery of a plastic or rubber sheath, and further coated with a conductive coating made by adding carbon black to acrylonitrile-butadiene rubber! It is characterized by being made of three 'J' cloths.

The sheath material of the present invention may be either plastic or rubber, and includes polyethylene, polyvinyl chloride, talolobrene, ethylene propylene, and the like.

Examples of nylon include nylon 6.66.610 and nylon 11.12, and nylon 11.12 is preferred in consideration of termite resistance, processability, hygroscopicity, and handleability.

Of course, as long as the material is mainly composed of nylon, it may be a copolymer or a blend.

The thickness of the nylon layer varies depending on the size of the cable, but it is generally provided at a thickness of about 11 In, and may be thinner for small cables and thicker for large cables.

Acrylonitrile-butadiene rubber is used for the purpose of entraining the carbon black binder and nylon sheath layer.

Acrylonitrile-butadiene rubber is acrylonitrile-butadiene rubber.
Although the properties change depending on the amount of acrylonitrile ω, bT that it is sufficient to use up to 15 to 50 IW% of acrylonitrile ω.
I have been bitten.

The molecular group is 10. There are various types, from ○00 liquid to so-called rubber and so-called several-packed ones, and any of them can be used.

This polymer has a low ω deterioration prevention material, e.g. 4°4−
Diobis-(6-t-butyl-3-methylphenol)
It is convenient to add etc.

Carbon black for imparting electrical properties includes tunnel black, furnace black, acetylene black,
It may be used as long as it can be added to acrylonitrile-butadiene rubber to impart conductivity.

The amount thereof is preferably about 50 to 300 parts by weight per 100 parts by weight of acrylonitrile-butadiene rubber.

A composition containing acrylonitrile-butadiene rubber and carbon black is dissolved in a suitable solvent such as methyl ethyl ketone and used as a ζ-mouth.

1f'l is 400 to 1 part of 200 particles of acrylonitrile-butadiene rubber and carbon black composition.
A preferred range is 2,000,0008 parts.

[Implementation fPI E Example 1000IRi copper conductor is wrapped with insulating paper, an aluminum sheath is placed around the core impregnated with insulating oil, and this outer periphery is covered with a polyvinyl chloride sheath with a thickness of 7M.○E cable. I used ta.

Apply nylon 11 to a thickness of 1 on the outer circumference of the polyvinyl chloride sheath.
, O/nm1. :II! I got exposed.

Next, 10,000 tons of Acryloni I~Lilubutadiene rubber.
A conductive paint consisting of 1 part of Ahidylene black, 10 parts of methyl ether ketone, and 80,07 parts of methyl ether ketone was applied.

The conductivity of the conductive layer is 70Ω-cIn, and from the withstand voltage and insulation resistance of the sheath, it is -1 minute for an external electrode for a window.

As with the withstand voltage test between the aluminum sheath and the conductive layer (earth) of this cable, the required insulation resistance based on the leakage current was 8 to 11, and sufficient electrode action was confirmed.

Meanwhile, connect the cable with two layers of dry cloth tape and lubricated cloth tape.
When the abrasion test was carried out 20 times using two tapes, no peeling of the paint or cracking occurred in both tapes.

Comparative example The same OF cable as in the example was used.

1.0 nylon 11 on the outer periphery of the polyvinyl chloride sheath
Applied to M.

Subsequently, a conductive paint consisting of 10 parts of vinyl chloride-vinyl acetate copolymer, 10 parts of adilene black, and 1 part of 80 g of a 2:1 mixed solvent of methyl ethyl ketone and perchloroethylene was applied.

It was noted that the conductivity of the conductive layer was 60 Ω-cm and that it could be sufficiently used as an external upper electrode.

However, in the dry cloth tape and wet cloth tape wear tests, the paint layer on the nylon sheath disappeared after 6 and 4 times, respectively.

[Effects of the Invention] As explained above, according to the present invention, a conductive paint is applied which is extremely advantageous for finding defective parts, incorrect parts, etc. of the sheath after transportation and installation. It becomes possible to provide ant-proof wires and cables.

Claims (1)

[Claims] (1) A termite-proof electric wire characterized by providing a nylon layer on the outer periphery of the plastic or rubber sheath of the electric wire/cable, and further coating this outer periphery with a conductive paint made of acrylonitrile-butadiene rubber added with carbon black. ·cable.