JPS5835009B2 - How to connect metal tube coated cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for connecting a metal tube-covered cable in which a conductor is sequentially covered with an insulator and a metal tube.

When connecting this type of cable, it is desirable that the connection work be easy, regardless of whether the connection is made after the cable is laid or before the cable is laid.
Particularly when connecting cables before installation, it is also desirable that the configuration and properties of the connection part be the same or very similar to other parts in order to facilitate the installation work.

However, the conventional connection method does not meet the above-mentioned requirements, as after connecting the conductors, a protective surface such as a steel pipe is attached to the outer periphery, so the connection part has a larger diameter and higher rigidity than other parts. Moreover, since the configuration and properties of the connection part are significantly different from those of other parts, it could not be used for connection before cable installation.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for connecting metal pipe coated cables that is easy to work with and does not interfere with cable installation even if it is performed before cable installation. This is the purpose.

An embodiment of the present invention will be described below with reference to the drawings.

In the figure, 1ay1b is a corrugated pipe covered cable,
A corrugated pipe 4a in which the conductors 2a and 2b are covered with an insulator 3a, t3b, the outer periphery is made of metal such as lead or aluminum, and a corrosion-resistant layer is provided on the outer periphery.
, 4b.

First, as shown in Fig. 1, each corrugated pipe 4
The insulators 3a, 3b are exposed by removing the ends of the conductors 2a, 2b to an appropriate length by peeling off the insulators 3a, 3b. to expose.

Thereafter, as shown in FIG. 2, the connecting tube 5 is fed and fitted around the outer periphery of one of the corrugated tube covered cables 1a.

That is, this connecting pipe body 5 is connected to the corrugated pipe 4a.
It is formed as a corrugated pipe of approximately the same diameter from the same metal material as t4b, and this connecting pipe body 5
The cable is heated and expanded so that its inner diameter is made slightly larger than the outer diameter of the one corrugated tube-covered cable 1a, and then fed into the outer periphery of the one corrugated tube-covered cable 1a and loosely fitted therein.

Then, the conductors 2a and 2b are connected by welding or through a sleeve (not shown) while maintaining a loose fit between the two conductors 2a and 2b as shown in FIG. A reinforcing insulating layer 6 is provided by wrapping insulating tape, insulating oil-impregnated paper, etc. around the exposed portion of the connecting portion, thereby forming a connection portion.

Thereafter, the connecting tube 5, which is loosely fitted to the one corrugated pipe covered cable 1a, is moved to the outer periphery of the connecting portion.

If this state is left for a while, the connection pipe 5
The corrugated pipe 4a returns to its original diameter through heat radiation and cooling.
It has approximately the same diameter as t 4 b, and both ends of the connecting pipe body 5 are welded and connected to the ends of each corrugated pipe 4a and 4b.

In this case, it goes without saying that the anti-corrosion layer at the end of each corrugated pipe 4ay4b should be removed in advance.

Note that since the connecting tube 5 is heated,
It is not possible to provide a corrosion-resistant layer on the outer circumferential surface of the connecting tube body 5 in advance. A corrosion-proofing tape γ is wrapped around the end of each corrugated pipe 4 a y 4 b from which the layer has been removed to perform corrosion-proofing treatment.

Therefore, if the corrugated pipe covered cable 1at1b is connected as described above, the reinforcing insulating layer 6 at the connection point
and the corrugated pitch etc. are almost the same as other parts,
As a result, it can be connected without making its rigidity, flexibility, etc. different from other parts.

As is clear from the above embodiments, the present invention involves feeding a connecting tube for covering the connecting portion of the conductor into the outer periphery of one of the metal tube-covered cables in advance and fitting it loosely, and then performing the conductor connecting work. After this is completed, the connecting tube is moved to the outer periphery of the conductor connection part, but when the connecting tube is sent to the outer periphery of one of the metal tube-sheathed cables and loosely fitted, the outer diameter of the former is smaller than the outer diameter of the former. Since it is only necessary that the inner diameter of the latter be slightly larger, there is no particular need to heat and expand the connecting tube as in the above embodiment, and the outer diameter can be increased by cooling and shrinking one of the metal tube-covered cables. It may be slightly smaller than the inner diameter of the connecting tube.

In particular, when connecting OF cables, the ends of the cables are sometimes cooled to prevent oil leakage.This cooling operation causes one cable to shrink, and in parallel, the connecting tube is connected to one cable. By feeding it into the outer periphery and loosely fitting it, the connection work can be easily performed without performing any new thermal operations.

Furthermore, although the above embodiment describes a case where a corrugated pipe covered cable is connected, the present invention is not limited to the above embodiment, and the present invention is not limited to the above embodiment. Needless to say, the present invention can also be applied to the case of connecting metal tube-covered cables made of metal tubes.

As is clear from the above description, according to the connection method of the present invention, a connecting tube that has approximately the same diameter and the same material as the metal tube-sheathed cable to be connected and is used to cover the connecting portion of the conductor is heated and expanded. , or by cooling and shrinking one of the metal tube-covered cables to be connected, the inner diameter of the connecting tube body is made slightly larger than the outer diameter of one of the metal tube-covered cables,
In this state, the connecting tube is sent in advance to the outer periphery of one of the metal pipe coated cables and loosely fitted, and after connecting the conductors and applying insulation coating to the outer periphery, the connecting tube in the loosely fitted state is The tube is moved to the connection part of the conductor, and both ends of the connecting tube are connected to the ends of each metal tube with the connecting tube and the metal tube coated cable having almost the same diameter. Therefore, it is possible to connect a metal tube coated cable with the structure and properties of the connection point being almost the same as other parts, and therefore, the connection method of the present invention can be applied to the metal tube coated cable before installation. Also, by interconnecting the cables, it is possible to obtain the effect that there is no hindrance to the installation work of a long metal tube-covered cable.

[Brief explanation of drawings]

1 to 3 are sectional views showing one embodiment of the present invention in order. 1 a t 1 b...Corrugated tube coated cable, 2 a, 2 b...Conductor, 3ay3b
...Insulator, 4 a, 4 b ... Corrugated pipe, 5 ... Connection pipe body.

Claims (1)

[Claims] 1 Metal tube-sheathed cables made by sequentially covering conductors with insulators and metal corrugated tubes are butted together for connection, and a connecting wire made of approximately the same diameter and the same material as that metal tube is placed on the outer periphery of one of the metal tube-sheathed cables. The pipe body is loosely fitted by feeding the one metal pipe coated cable in a state in which it is cooled and shrunk or the connection pipe body is heated and expanded, and while maintaining this state, connects the conductors and insulates the outer periphery. A coating is applied to form a connecting portion, and then the connecting tube is moved to the outer periphery of the connecting portion, and both ends thereof are attached to the ends of each of the metal tubes in a state where the connecting tube has approximately the same diameter as the metal tube. A method for connecting metal tube coated cables, which is characterized in that they are butted against each other and connected to have the same diameter.