JPS6214804B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a reinforced optical cable for an optical cable composite overhead ground wire in which an optical cable is embedded in an overhead ground wire for a power transmission line.

In recent years, in the field of overhead power transmission, as power transmission capacity has increased, power generation and substation facilities have become larger, and power generation and substations have tended to be located in remote locations. In order to cope with this, communication lines have been used such as power carriers and microwaves, but the former has limited information capacity and cannot centralize grid protection control, and the latter is limited by location conditions and other communication services. There were drawbacks such as the difficulty in securing lines due to the diversification of networks.

These problems are solved by using an optical cable composite overhead ground wire in which an optical cable is embedded within the overhead ground wire. Various structures can be considered for the optical cable composite overhead ground wire, but for ease of manufacturing and to protect the optical cable during manufacturing and use, it is recommended to protect a single optical cable or multiple optical cables with a metal pipe.
A composite overhead ground wire in which this wire is twisted together with other overhead ground wire constituent wires is preferred.

The present invention relates to a method for manufacturing this type of metal pipe sheath reinforced optical cable. Conventional methods for manufacturing metal pipe sheath reinforced optical cables include:
The methods used include inserting an optical cable into a pipe prepared in advance, and forming a metal tape into a circular shape around the optical cable and welding the seam.
In the former, there is a limit to the length of the cable that can be inserted,
In addition, the latter method has the disadvantage that it is difficult to form a small-diameter pipe, and the cable protective layer is damaged by the heat effect during welding.

In view of the above points, the present invention provides a method for economically manufacturing a long reinforced optical cable for an optical cable composite overhead ground wire without damaging the optical cable.

The embodiments shown in the drawings will be explained below.

As shown in FIG. 1, a metal tape B sent out from a metal tape supply 2 is attached to an optical cable A sent out from an optical cable supply 1 through a cleaning tank 3, a tape slitter 4, guide rollers 5 and 6, and then vertically spliced by a forming machine 7. A pipe with an inner diameter of 4 mmφ or more is coated and the seam portion is welded using a welding machine 8.

9 indicates a squeeze roll. Immediately after welding, the die or roll 1 is cooled in a cooling tank 10.
1, the cable is expanded into a predetermined shape to form a metal-coated optical cable C, which is then wound onto a winder 12. 2A shows a sectional view taken along the line aa' in FIG. 1, and FIG. 2A shows a sectional view taken along the line bb' in the same figure.

Here, the pipe with an inner diameter of 4 mmφ or more is 4 mm.
This is because if the diameter is less than φ, the optical cable protective layer will deteriorate due to thermal effects during welding.

Furthermore, when expanding the pipe, there is an advantage that the wall thickness of the pipe can be made more uniform if the pipe is expanded using a hollow floating plug provided with a passage for the optical cable, rather than simply drawing it by air. Further, the welding itself may be TIG welding, high frequency welding, or other known methods.

Next, examples of the present invention will be shown.

5052, Al alloy 18.8mm width x 0.4mm thick tape 0.9mm
It was supplied vertically to a 4-core optical cable, formed into a concentric pipe with an outer diameter of 6 mm, and the seam was TIG welded. Immediately after welding, the pipe was cooled with water and expanded to an outer diameter of 4.2 mmφ without bending the pipe. At this time, the optical cable was not subject to thermal or mechanical deterioration.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the method of the present invention, FIG. 2A is a sectional view taken along the line aa' in FIG. 1, and FIG. 2 is a sectional view taken along the line bb' in the same figure. 1 is an optical cable supply, 2 is a metal tape supply, 3 is a cleaning tank, 4 is a tape slitter,
5 and 6 are guide rolls, 7 is a molding machine, 8 is a welding machine, 9 is a squeeze roll, 10 is a cooling machine, 11 is a die, 12 is a winding machine, A is an optical cable, B is a metal tape, and C is a metal coating. optical cable.

Claims (1)

[Claims] 1. Place metal tape around the multi-core optical cable with an inner diameter of 4
A method for producing a reinforced optical cable, which is characterized by forming the cable to a diameter of mm or more, welding the seam, and immediately elongating it using dies or rolls after cooling.