JPH026283B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for repairing bare electric wires, and particularly to a method suitable for repairing an overhead ground wire with a built-in optical cable.

In general, overhead ground wires installed above power transmission lines are susceptible to damage such as wire melting due to lightning strikes due to their purpose, and when such damage occurs, conventional methods have been to remove the overhead ground wire. This was completely removed and replaced with a new one, but recently, optical cable composite type overhead ground wires, which have an optical cable built into the center, have a structure made only of stranded metal wires. However, as mentioned above, the optical cable for signal transmission is housed inside the cable, so even if it is damaged, it is not possible to simply replace it with another one. Therefore, in the case of a bare electric wire such as an optical cable composite type overhead ground wire, the damaged portion must be repaired so as not to adversely affect the built-in optical cable.

The present invention provides a method for repairing bare electric wires, which has been made in view of the above points.

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

In FIGS. 1 and 2, the bare wires designated as a whole by reference numeral 1 include a large number of metal wires 11A,
11B, . . . and an inner layer strand 12 consisting of a large number of metal wires 12A, 12B, . . . are twisted together.

Damage to electric wires caused by lightning usually extends to two or three adjacent strands, as shown by reference numeral 4 in FIG. 1, and may even extend to the inner strands in the radial direction of the wire.

The first step in the repair method of this invention is the third step.
As shown in the figure, a stranded wire 11 with a damaged part 4
The strands 11A _, 11B, . The damaged part 4 is exposed over _two parts. For this reason, as shown in FIG.
is cut 5 over its entire circumference to obtain each strand 11.
A, 11B,... are divided into left and right. Damaged part 4
When the wires reach the inner layer strands 12, of course, cut up to the inner layer strands 12 and cut each of the strands 12A, 1.
2B, . . . are also expanded in the same manner as described above. Although not shown at this time, in Fig. 3, the inner layer strand 1
2, the optical cable protection tube 2 is exposed over a length l ₂ .

Next, as shown in FIG. 4, a vertically divided steel sleeve 6 having a length at least equal to the exposed length l ₂ of the inner layer strands 12 is attached to the exposed portion of the inner layer strands 12 having a length l ₂ . Fit into place. It is easy to use this vertically divided sleeve 6 when it is divided into two parts.

Next, each of the strands 11A, 11B, etc., which have been expanded radially outward in the previous step, are bent back onto the steel vertically split sleeve 6 and brought into close contact with the vertically split sleeve 6 at least. A steel ladder box-shaped sleeve 7 having the same length as shown in FIG. 6 is fitted from the radial direction and compressed by a compressor. As is clear from the figure, the ladderbox-shaped sleeve 7 has a main body with a substantially U-shaped cross section and a sliding lid 71 inserted into it. 6 and each strand 11A, 11B, . . . closely attached thereto.
is compressed toward the center of the bare wire 1 and tightened integrally, completing the repair work of the present invention.

According to the repair method of the present invention, the damaged part of the bare wire is covered with a steel ladder box sleeve and compressed, so that the damaged part is restored to a state having sufficient mechanical strength and electrical conductivity. be able to.
Especially in the case of bare wires with built-in optical cables,
The optical cable is protected by the vertically divided steel sleeve provided on the inner layer of the steel ladder sleeve, so even though a large compressive force is applied when the ladder sleeve is crimped, the internal This has the advantage that there is no mechanical adverse effect on the optical cable.

[Brief explanation of drawings]

Figures 1 to 6 are explanatory diagrams of the method of this invention, where Figure 1 is a side view showing a damaged bare wire, and Figure 2 is a side view showing a damaged bare wire.
The figure is a sectional view taken along the - line in Figure 1, Figure 3 is a partially cutaway side view showing the state in which each strand is expanded at the cut point of the damaged stranded wire, and Figure 4 is a vertically split sleeve fitted. FIG. 5 is a partially cutaway side view showing a state in which the ladderbox-shaped sleeve is crimped, and FIG. 6 is a perspective view of the ladderbox-shaped sleeve. 1... Bare electric wire, 11... Outer layer stranded wire, 11A, 1
1B...Element wire, 12...Inner layer twisted wire, 12A, 12
B...Element wire, 4...Damaged part, 6...Steel vertically split sleeve, 7...Steel ladder box type sleeve.

Claims (1)

[Claims] 1 A stranded wire with a damaged part in a bare electric wire is cut around the entire circumference at the location of the damaged part, and each strand making up the stranded wire is expanded radially outward to form an inner layer stranded wire or exposing the central layer over a length l ₂ greater than the longitudinal width l ₁ of the damaged area at the damaged area; a step of fitting a vertically divided steel sleeve having a length at least equivalent to the exposed length l ₂ ; and bending each strand expanded outward in the radial direction onto the vertically divided steel sleeve. A step of returning the vertically divided sleeves to bring them into close contact with each other, and a step of compressing the vertically divided sleeves by fitting a steel ladder box-shaped sleeve having at least the same length as the vertically divided sleeves onto each of the strands tightly adhered to the vertically divided sleeves. A method for repairing bare electric wires having