JP3286256B2 - Termite damage prevention pipe joints and rubber rings used in underground electrical lines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a power cable,
The present invention relates to a pipe joint for preventing termite damage to a cable in an underground electric line such as a communication cable and a rubber ring used for the joint.

[0002]

2. Description of the Related Art Today, when international trade is active, the invasion of termites from other countries has caused a problem of termite damage to cables in underground electric lines, which was not a problem with conventional termites in Japan. I have. First, as a means of preventing this damage, it is considered that a pipe or a cable jacket forming a conduit is made to be termite-proof, by applying a termite-controlling agent to the pipe or the cable jacket. Or impregnated.

[0003] However, the application of the medicine to the pipe and the jacket becomes large-scale, and the operation becomes complicated. In addition, the impregnation with a chemical cannot be adopted for existing pipes and existing cables.

[0004] It is an object of the present invention to provide a means for preventing termites from being harmed by the work, which is easy under the above circumstances, and which can be employed in existing pipelines.

[0005]

In order to achieve the above object, according to the present invention, a termite intrusion prevention process is applied to a joint of a conduit in an underground electric wire line.

[0006] In the existing underground electric wire line, when it is confirmed that the cable therein is damaged by termites, no through hole (ant canal) is formed in the pipe, and the rubber ring at the joint of the pipes. Was eaten, and there was an ant path in the rubber ring. For this reason, in order to prevent termites from entering the intervening surface of the rubber ring, that is, the joining surface of the pipe, the joint is subjected to termite intrusion prevention processing. This process can be employed not only when a new pipeline is installed, but also for an existing pipeline.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention is as follows.
An underground electric wire line with a cable laid in the soil and a cable passed through the conduit, and a rubber ring interposed between the ends of the two tubes at the joint of the conduit and a termite-controlling chemical added to the rubber ring By using the above, a configuration in which the termite intrusion prevention processing is performed can be obtained.

The above-mentioned tube may be a conventional fume tube, steel tube, glass fiber reinforced plastic tube or the like, but is preferably impregnated with a termite-controlling agent.

The above termite-controlling agents include Japanese Patent Publication No. 59-170.
No. 83, Japanese Patent Publication No. 59-40125,
Various existing ones described in -286816 and the like can be adopted.

[0010]

1 and 2 show one embodiment of the present invention. In this embodiment, a termite-controlling chemical is added to rubber rings 1a and 1b of a pipe joint where a pipe joint P is fitted to one pipe 2. FIG. And a mixture kneaded and formed. That is, styrene-butadiene rubber (SBR) is added to a termite-controlling agent (for example, Sumitomo Chemical Co., Ltd.) at the joint between the tubes 2 and 2 through which the cable a is inserted.
Rubber rings 1a and 1b formed by adding 0.2% by weight of trade name: Exmin (commonly called permethrin) were employed. At the time of molding, a compound of an appropriate amount of an ethylene-vinyl acetate copolymer (EVA) and Exmin is prepared, and the compound is mixed with SBR.
Exmin was evenly dispersed in SBR with affinity for both BR and Exmin.

As shown in FIG. 2, the rubber rings 1a and 1b are mounted on the receiving side of the tube 2, and the two tubes 2 and 2 are connected by inserting the insertion openings of the other tubes 2 as indicated by arrows. I do. In this joint structure, no termites penetrated into the pipes 2 and 2 even when they were put into the soil of the termite group.

[0012] The amount of the termite repellent added is as follows.
a, 1b may be appropriately selected without impairing the functions thereof, but with an addition amount of 0.1 to 0.4% by weight, satisfactory ones can be obtained in tensile, hardness, aging, and permanent set tests. Was. The optimum amount was 0.2% by weight.

The above embodiment relates to the joint of the pipes 2 and 2 of the same kind and the same diameter. In the case of such a pipe joint P, for example, a stopper 3 integral with the rubber ring 1b is provided at the center as shown in FIG.
When the similar rubber rings 1a and 1b are used also in a device provided with a worm, termite control can be performed.

Also, tubes 2, 2 having different outer diameters, such as tubes of different diameters, etc.
When connecting Polycon FRP pipes to different kinds of pipes such as steel pipes and FRP pipes, the cross-sectional dimensions (outer diameter) even if they are the same diameter
In this case, the pipe joints P shown in FIGS. 4A to 4C are used, but the rubber rings 1a and 1b can also be used for similar termites. Further, as shown in FIGS.
The same applies to an intermediate joint P for adjusting dimensions in the middle of a pipe, a flexible joint P shown in FIG. 8, and a universal pipe P shown in FIG. In these cases, the rubber rings 1a and 1b may be integrated (FIGS. 5 and 6).

[0015]

As described above, the present invention prevents invasion of termites at the pipe joint as described above, so that the termites of cables can be effectively and inexpensively reduced not only in new installations but also in existing underground electric wire lines. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a pipe joint according to an embodiment.

FIG. 2 is a sectional view for explaining the operation of the main part of the embodiment.

FIG. 3 is a sectional view of a pipe joint according to another embodiment.

FIGS. 4A, 4B, and 4C are cross-sectional views of other embodiments.

FIG. 5A is a perspective view of a pipe joint according to another embodiment,
(B) is the same sectional view

FIG. 6A is a perspective view of a pipe joint according to another embodiment,
(B) is the same sectional view

FIG. 7A is a perspective view of a pipe joint according to another embodiment,
(B) is the same sectional view

FIG. 8 is a sectional view of a pipe joint according to another embodiment.

FIG. 9 is a sectional view of a pipe joint according to another embodiment.

[Explanation of symbols]

 1a, 1b Rubber ring 2 pipe P fitting a cable

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuhito Hasegawa 1-112 Kitahorie, Nishi-ku, Osaka City Inside Kurimoto Iron Works Co., Ltd. (72) Inventor Shoichi Ochi 1-12-19 Kitahorie, Nishi-ku, Osaka City No. Kurimoto Iron Works Co., Ltd. (72) Inventor Tsuyoshi Naito 1-12-19 Kitahorie, Nishi-ku, Osaka City Co., Ltd. Kurimoto Iron Works Co., Ltd. (56) Reference Real Opening 2-34232 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) H02G 9/06 F16L 21/02

Claims (2)

(57) [Claims] 1. A receiving port of one pipe 2 is provided with rubber rings 1a and 1b.
And the two pipes 2 and 2 are connected by inserting the insertion port of the other pipe 2
Thereafter, this connection is repeated to form a pipeline,
Road and fabric set in the soil and in underground electric line through a cable a to the conduit, the rubber ring 1a, anti-termite agents to 1b
A termite infestation prevention pipe joint in an underground electric wire line , wherein a termite intrusion prevention treatment is applied to a joint between the receiving port and the insertion port using a material to which terminator is added . 2. A rubber ring to which said termite-controlling chemical is added for use in a termite corrosion-preventing pipe joint in an underground electric wire line according to claim 1 .