JP2797677B2 - Lightweight electric wire clamping method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention uses a steel core aluminum stranded wire (hereinafter, also referred to as “ACSR”) having a hollow portion formed in an intermediate layer in order to achieve weight reduction. The present invention relates to a novel lightweight electric wire clamping method for compressing and fixing with a clamp.

[Prior Art] In recent years, reduction in the weight of ACSR type transmission lines has been studied.

In particular, in the next transmission line for UHV, the wire diameter must be large for corona countermeasures, but lighter wires are required due to the problem of overhead wire economy. As this lightweight electric wire, there has been proposed an electric wire in which a hollow portion is formed by extracting some of the aluminum wires forming an intermediate layer by being joined by a steel core layer and an outermost layer.

[Problems to be Solved by the Invention] By the way, in order to put the above-mentioned light-weight electric wire into practical use, a method of fixing the electric wire to a clamp (extended wire clamp, end clamp, etc.) as an accessory thereof must be established.

In particular, in the case of detention or connection by a compression type clamp, because of the method of compressing and fixing the end of the electric wire, when trying to forcibly compress the electric wire having the hollow portion as described above,
The wires constituting the electric wires are deformed irregularly, and there is a problem that it is difficult to obtain a constant gripping strength.
In order to obtain a sufficient gripping force by the compression of the clamp, the outer diameter of the electric wire must be greatly reduced in order to make the inside of the electric wire dense. With such a fixing method, the workability at the time of the overhead wire construction also becomes extremely poor.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a method of clamping a lightweight electric wire, in which a lightweight ACSR can be appropriately and easily obtained by using a general-purpose compression clamp.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an intermediate layer formed by twisting a plurality of aluminum wires around the steel core layer between the steel core layer and the outermost layer. A method for clamping and compressing an end portion of a lightweight electric wire in which a hollow portion formed by extracting some of the twisted aluminum wires is formed in the intermediate layer. After inserting and filling an intervening material into the hollow portion from the end of the electric wire for the length of the compressed portion, clamp compression is performed.

Also, when inserting the inclusion into the hollow portion,
It is desirable that the inclusion be formed to have a substantially fan-shaped cross section and be formed in accordance with the pitch of the aluminum strand.

[Operation] In the middle layer of the above-described lightweight electric wire, a spiral hollow portion is formed as if some of the twisted aluminum wires were removed. Therefore, the preform is applied to the inclusions in accordance with the pitch of the aluminum wires. Also, the inclusions are formed in advance in a substantially fan-shaped cross section. Thus, the inclusion can be smoothly inserted into the hollow portion, and the inclusion can be densely filled in the hollow portion.

Therefore, after inserting and filling the hollow part of the electric wire from the end of the electric wire for the length of the compressed part, and by performing clamp compression, the aluminum strand is not significantly deformed by compression, and it has sufficient grip strength and lightweight. The model wire can be pulled or connected.

Example Next, an example of the present invention will be described.

As shown in FIG. 1, the lightweight electric wire 1 has an aluminum wire 3 twisted around a steel core layer 2 and further has wires 4, 5, 6 having different cross-sectional shapes to form an outermost layer 8 on the outer periphery thereof. Are twisted together. A hollow portion 7 is formed in the intermediate layer 9 formed by twisting the aluminum wires 3 by extracting some of the twisted aluminum wires 3 or the like.
Thereby, the weight of the electric wire is reduced.

As described above, when the lightweight electric wire 1 is held by a general-purpose compression clamp, if the end portion of the electric wire is forcibly compressed, the strand is irregularly deformed.

Therefore, in the present embodiment, an insert 10 made of aluminum or an aluminum alloy wire having a sectoral cross section is inserted into the hollow portion 7 from the end of the electric wire for about the length of the compressed portion, and then clamped and compressed. To

The width of the inclusion 10 is set to be slightly smaller than the width of the aluminum wire 3, and the length is set to be about the length of the compressed portion of the clamp. When inserting the inclusion 10 into the hollow portion 7, the inclusion 10 is formed in a spiral shape in accordance with the pitch of the aluminum strand 3.

By performing the clamp compression while the hollow portion 7 is filled with the inclusions 10, the lightweight electric wire 1 can be retained with sufficient gripping strength without significantly deforming the aluminum wire 3. This allows the lightweight electric wire 1 to be appropriately and easily pulled or connected using a general-purpose compression clamp.

Since the inclusions 10 are formed in a fan-shaped cross section, a plurality of inclusions 10 are inserted into the hollow portion 7 and filled, so that the gap can be minimized and the inside of the electric wire 1 can be made dense. In addition, by inserting the preform on the inclusion 10 in accordance with the pitch of the aluminum wires 3, the insertion of the inclusion 10 into the hollow portion 7 can be performed smoothly, and the workability can be improved. .

[Effects of the Invention] In summary, according to the present invention, it is possible to apply a general-purpose compression clamp to a light-weight electric wire configured to have a hollow portion inside the electric wire in order to reduce the weight of the electric wire. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention. In the figure, 1 is a lightweight electric wire, 2 is a steel core layer, 3 is an aluminum wire,
7 is a hollow portion, 8 is an outermost layer, 9 is an intermediate layer, and 10 is an inclusion.

Claims (2)

(57) [Claims] An intermediate layer comprising a plurality of aluminum wires stranded on the outer periphery of the steel core layer is provided between the steel core layer and the outermost layer, and an aluminum element stranded on the intermediate layer is provided. In a method of clamping and compressing an end of a lightweight electric wire having a hollow portion in which some of the wires are removed, an intermediate portion is inserted into the hollow portion of the intermediate layer from the end portion by compression. A method for clamping a light-weight electric wire, characterized in that the clamp is compressed after insertion and filling. 2. The method according to claim 1, wherein when the inclusion is inserted into the hollow portion, the inclusion is formed to have a substantially fan-shaped cross section and is formed in accordance with the pitch of the aluminum strand. The method for clamping a lightweight electric wire as described.