JPH0116081B2 - - Google Patents

Description

[Detailed Description of the Invention] "Background and Objects of the Invention" The present invention is an improved method for adjusting the slack of a wire-shaped body that is wired over a long span, such as an overhead power transmission line or a steel cable for a cableway, to the required slack. Concerning line tension methods.

An example will be explained below using a power transmission line.

Overhead power transmission lines are installed between steel towers that are constructed over long spans, and a so-called come-along method is used to connect the overhead power lines, and a so-called tension line is carried out in which the wires are grasped with a come-along and pulled to the towers. Adjustment work will be carried out for the slackness of the overhead wires. In the case of normal overhead wire spans, there are no problems caused by such tensioning work, but in river crossings as shown in Figure 1, many steel towers T ₁ to _{T 8} have been constructed.
Since the overhead line is stretched over several thousand meters at a time, the length of the electric wire C becomes particularly long, and when it is strung, a huge load is applied to the come-along gripping part, which causes the steel-core aluminum stranded wire to Accidents such as damage to the aluminum layer of the wire and breakage may occur. Furthermore, in the case of smooth body wires, loose wires, etc., the come-along often slips if the wire tension is large.

In order to avoid such inconveniences, methods have been proposed, such as attaching auxiliary tools such as PG clamps to the come-along to prevent slipping, and the come-along-less construction method, which does not use the come-along at all, but each method has its drawbacks and is not always effective. It cannot be said that it is being utilized.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to easily and organically wear a plurality of commonly used come-alongs, and to enable come-alongs to be used even during tension line work under heavy overhead wire tension. It is an object of the present invention to provide a wire tensioning method that can share the load and tension the wire without fearing the above-mentioned damage to the wire.

"Summary of the Invention" That is, the present invention has been made by focusing on the attachment of a plurality of come-alongs, which has not even occurred to the user's mind in the past, and the gist thereof is 1. To draw a linear object to a pedestal. To adjust the slackness of the linear body, a plurality of come-alongs are attached to the strained linear body,
A pulley is attached to each come-along, and the pulley is connected to a pulley separately attached to a pedestal via a single pull rope, and by pulling one end of the pull rope, the strain load is shared between each come-along. A tensioning method for the linear body that adjusts the slackness of the linear body.

2. When tightening a linear body in which the slackness of the linear body is adjusted by drawing the linear body to a pedestal, a plurality of come-alongs are attached to the linear body to be strained,
A pulley is attached to each come-along, and a pulley is also attached to the pedestal side, and a yoke having a separate group of pulleys is disposed between the come-along and the pedestal at a position facing these pulleys, and the pulley of the come-along and A linear body that adjusts the slackness of the linear body by connecting the pulley on the yoke, the pulley on the pedestal, and the pulley on the yoke separately with different pull ropes, and pulling the pull rope on the pedestal side. It's in the tension method.

"Example" This will be explained below based on examples.

Figures 2 and 3 show how the electric wire C is strung. A plurality of general-purpose come-alongs K ₁ , K ₂ , K ₃ are attached to the electric wire C, and each come-along is also connected with a general-purpose come-along. Pulleys S and S are attached. A is a pedestal that serves as a support base for the tension line, and in Figure 2, the arm of the steel tower is used as the pedestal.
FIG. 3 similarly illustrates the case of using an anchor block as the pedestal. The same pulleys are also on the pedestal side.
As shown in the figure, the come-along pulleys S, S and the pulleys S', S' on the pedestal side are connected by a single pull rope W. One end of the pull rope W is fixed to the pedestal A, and the other end is wound up by an engine car E (not shown). If it is held in this way, all the loads applied to the electric wire C will be transferred to the three come-alongs K ₁ , K ₂ , K ₃ (it goes without saying that the number is not limited to three but may be more than one) As a result, the load on one come-along is reduced to one-third, and for example, in the case of Figure 1, the tension load of 9 tons is unthinkable for ordinary overhead wires. Although tension is applied, since the load is distributed as described above, there is no risk of accidents such as damage or breakage of the aluminum layer as described above.

Moreover, although each rope is equipped with multiple pulleys, the actual tensioning work involves only pulling a single rope, so there is no substantial difference from conventional tensioning work.

FIG. 4 shows yet another embodiment, in which yokes Y ₁ , Y ₂ are separately interposed between the electric wire and the pedestal, and pulleys S, S on the come-along side and the pulleys S and S on the yoke Y ₁ side are connected with a pulling rope W ₁ , and the yoke Y ₁
The pulleys S, S on the side and the pulleys S, S on the yoke _Y2 side are connected by a separate pull rope _W2 .
By interposing the yoke in the middle in this way, the tension of the overhead wire becomes more dispersed, and the load sharing becomes smaller in each come-along. Furthermore, a pull rope connects the P part in the figure between yokes Y ₁ and Y ₂ .
Since the tension applied to the entire W ₂ is also reduced,
That's how thin the rope will be.

The above explanation is based on the case of tightening electric wires, but it can also be applied to the construction of wires coated with a large amount of grease, such as ropes for ropeways, or for removing slack. You can make it work.

``Effects of the Invention'' As described above, the wire tensioning method according to the present invention can be used simply by using conventional come-alongs or pulleys as they are, and can be used in cases where strong tension is applied during overhead wires, or when special wires are being strained. This makes it possible to close lines extremely safely and with high reliability in situations where lines are closed, and its usefulness should be highly evaluated.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing how electric wires are laid across a river, and FIGS. 2 to 4 are explanatory diagrams showing three embodiments of the present invention. A...cradle, C...wire, K...come-along, S...pulley, W...pull rope, Y...yoke.

Claims (1)

[Claims] 1. In the tensioning of a linear body in which the slackness of the linear body is adjusted by drawing the linear body to a pedestal, a plurality of come-alongs are attached to the linear body to be strained, and each A pulley is attached to the come-along, and this pulley is connected to a pulley separately attached to a pedestal via a single pull rope, and by pulling one end of the pull rope, the tension load is shared between each come-along. A tensioning method for the linear body that adjusts the slackness of the linear body. 2. When straining a linear body in which the slackness of the linear body is adjusted by drawing the linear body to a pedestal, a plurality of come-alongs are attached to the linear body to be strained, and a pulley is attached to each come-along. A pulley is also attached to the pedestal side, and a yoke having a separate group of pulleys is arranged between the come-along and the pedestal in a position opposite to these pulleys, and the pulley of the come-along, the pulley of the yoke, and the pedestal are provided. A method of tensioning a linear body in which the pulley of the yoke and the pulley of the yoke are connected separately with different pull ropes, and the slackness of the linear body is adjusted by pulling the pull rope on the pedestal side.