JPS5939844B2 - Slack-suppressing electric wire and its installation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved ground motion suppressing electric wire and a method for constructing the same.

Steel-core aluminum stranded wires are often used as overhead power transmission lines, and they are made of a composite material with an integrated aluminum stranded wire layer surrounding the steel core. The stranded wire layers share the role of conductive members.

With such a configuration, when a temperature rise occurs due to energization, the coefficient of linear expansion becomes a composite value of steel and aluminum, and as a result, it becomes a value that approximates the coefficient of linear expansion of aluminum. If only steel could share the tension, steel has a coefficient of linear expansion that is about half that of aluminum, so it would be possible to significantly reduce the elongation of wires and the deterioration of wires when the temperature rises. In recent years, the electric power situation has come to require an increase in current carrying capacity. Naturally, the temperature of the wire itself increases when it is energized, and as a result, the wire expands and the ground deformation decreases. However, the ground insulation spacing of high-voltage overhead power transmission lines is regulated for safety reasons, and it is not allowed to reduce the ground resistance unnecessarily.

Therefore, increasing the current carrying capacity of existing steel towers will naturally cause vibrations. Considering the above-mentioned circumstances, the earth movement suppressing electric wire was developed in order to minimize the drop in ground movement and secure current carrying capacity by ensuring that only the steel core shares the tension of the overhead wire.

Conventionally, this type of electric wire has been proposed as a loose electric wire in which aluminum wires formed into a fan shape are twisted together, or in which a small gap is created between the steel core and the aluminum strands by considering the wire structure. .

However, this loose electric wire was difficult to manufacture, and in order to connect it to the overhead line, it was necessary to replace the come-along, which required complicated overhead wiring work, making it difficult to put it into practical use. The present invention aims to provide a new ground deformation suppressing electric wire and a method for constructing the same, which eliminates the above-mentioned drawbacks.

This will be explained below using examples.

An aluminum sleeve for a straight sleeve as shown in FIG. 2 is inserted into a normal steel-core aluminum stranded wire in advance, and tie clamps are crimped to both ends of the overhead wire span, and both tie clamps are held between the steel towers.

In this case, the wires may be extended and strung using normal overhead wire construction methods, but if possible, the span of the tower should be precisely measured in advance, and the length of the wires to be wired in that span should be precisely determined on the ground in advance. It is preferable to use a prefabricated overhead wire construction method in which the wire is cut to length, a detention clamp is crimped on the end of the wire on the ground, and then the wire is stretched. As shown in Fig. 1, the aluminum strands 2 of the steel-core aluminum strands 10 are connected near the ends of the deep wired steel-core aluminum stranded wires or in the middle of the suspension tower (this can be selected as necessary). Cut everything, leaving only the steel core 1.

In this way, since the overhead wire tension is applied to the steel core aluminum stranded wires 10, the stress of the aluminum strands 2 is gradually relaxed and shrinks in the direction of the arrow in FIG.
The situation is such that only one person has shared the responsibility. The gap 5 thus created is wrapped with, for example, a soft aluminum wire (it is not limited to this, and of course, aluminum collar or anti-corrosion compound mixture can be selected as required), as shown in FIG. 2.
Fill with the filling proboscis as shown. After that, the aluminum collar 4 is moved to a predetermined position as shown in Fig. 2, and the third
Compress and fix as shown. At this stage of compression and fixation, the aluminum stranded wire 2 is once again pushed out in the longitudinal direction of the wire.
This results in further contributing to stress relaxation in the aluminum stranded wire layer. According to the above-mentioned overhead wire method and the sag-suppressing electric wire formed thereby, the overhead wire tension can be completely shared only by the steel core, and the linear expansion during temperature rise can be reduced to the coefficient of linear expansion of the steel core alone. You can make it happen. Moreover, the electric wire does not need to have a special structure and is extremely easy to construct, so it can be put to practical use in industry, and its effects are great.

[Brief explanation of the drawing]

FIGS. 1 to 3 are explanatory diagrams showing the process of making the electric wire into a sag suppressing type according to the present invention. 1: Steel core, 2: Aluminum stranded wire, 3: Filler, 4: Aluminum sleeve, 10: Steel core aluminum stranded wire.

Claims (1)

[Scope of Claims] 1. A cutting gap is provided in the aluminum stranded wire layer at a predetermined position between the detention clamps of an electric wire made of steel-core aluminum stranded wire with detention clamps crimped at both ends, and the gap is filled. A sag-reducing electric wire characterized in that a filling material and an electric wire are compressed together by a compression sleeve. 2. After extending an electric wire made of steel-core aluminum stranded wire between the steel towers and securing it with a restraining clamp, all the aluminum stranded wire layers of the electric wire are cut so that the tension is shared only with the steel core,
A slack-suppressing electric wire characterized by providing a filler in the gap between the cut parts of the aluminum stranded wire layer generated in the process, and then fitting a compression sleeve to the filler and the electric wire on both sides of the filler and crimping the entire wire. construction method. 3. The construction as set forth in claim 2, characterized in that the electric wire is precisely cut to a length that matches the tower span and is extended on the ground with a retaining clamp crimped. Method.