JPH05184022A - Work method for loosening and extending large-sized long power cable - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a construction method capable of continuously extending a large-sized long power cable wound in a large container while giving slack without giving excessive force. [Structure] A scaffold 3 is assembled along the extension direction of the cable from the side of the large-sized container 1 in which a large-sized long power cable 13 is wound and installed on a turntable 1a, and the position of the scaffold near the container side and the extended line. The wire drawing machines 8 and 9 are attached to positions closer to the sides, and a slack absorption section 1 is provided on the scaffold between the front and rear of the wire drawing machines, so that the cable fed out by the rotation of the large container is drawn toward the container side. Then, the wire is pulled up on the scaffolding and further given a predetermined slack 14 in the slack absorbing section, and then sent out to the laying route by a wire drawing machine near the wire drawing side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for continuously extending a large-sized long power cable, and particularly, the inertial force of a large container and the inertial force of a wire drawing machine are reduced. The present invention relates to the provision of a slackening and wire-drawing method for preliminarily imparting the slack of a cable required in relation to rotation.

[0002]

[Prior Art and Problems to be Solved by the Invention] In general,
The power cable was wound on a wooden or metal drum for shipment / transportation. In that case, the cable length was limited to 800 to 1000 m, though depending on the size and weight of the cable. That was also the case due to road restrictions.

By the way, in the case of crossing a river or crossing a tunnel, a cable length of 3000 to 5000 m may be required. In such a case, it is not possible to wind the drum at the time of shipping / transporting, and therefore, it is necessary to roll the product horizontally in a large container before shipping. Then, when the cable is extended, the container is set on the turntable and the operation of the turntable and the operation of the wire-drawing machine arranged on the laying route are jointly sent out.

Since such a container corresponds to a long cable, it becomes considerably large, and the weight of the container itself, the cable, and the turntable is 10%.
It reaches over 0 tons, and at the start / stop of operation,
It was necessary to start slowly and stop slowly. In particular, even if an operation stop signal is issued during an emergency stop, the turntable and container, which have a large own weight (load), will have a very large inertial force and must be stopped after a certain braking distance to prevent damage to each part. I had no choice. The need for a braking distance means that when a long cable is drawn, the difference in inertia between the container operation system and the wire drawing machine operation system must be generated as slack in the cable. It is required to absorb the slack without applying stress and to continuously extend the cable, but the conventional cable drawing method, which is a long laying of 1000 m at most, satisfies such a requirement. I couldn't.

In view of the above situation, the present invention provides a construction method capable of continuously extending a large-sized long-length power cable wound in a large-sized container while applying slack without giving excessive force. There is a purpose in particular.

[0006]

The method for slackening and extending a large-sized long power cable provided by the present invention provides a method for removing a large-sized long power cable from the side of a large container on which a large-length long power cable is wound and installed on a turntable. Assemble the scaffold along the line drawing direction, install the wire drawing machine at the position near the container side of the scaffold and the position near the wire drawing side, and provide a slack absorbing section on the scaffold between the front and rear of those wire drawing machines, The cable drawn out by the rotation of a large container is pulled up on the scaffold by a wire drawing machine near the container side, and after giving a certain amount of slack in the slack absorbing section, it is sent to the laying route by the wire drawing machine near the wire drawing side. It is in.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a preferred embodiment of a method for slackening and drawing a large-sized power cable according to the present invention,
(A) is a plan view and (B) is a side (front) view. In this embodiment, the large size power cable is DC500.
kvOF cable (cable outer diameter 130mmφ, weight 45
(kg / m) This is an example using 1 article 5100 m.

The large container indicated by reference numeral 1 has an inner diameter of 3
The cable has a diameter of 500 mm, an outer diameter of 8000 mm, and a height of 3500 mm, and the above cable has 5100 mm wound therein and is set on the turntable 1a, and a cable shooter 2 is attached.

A scaffold 3 is assembled from the installation position of the large container 1 along the extending direction of the cable. The scaffolding 3 is assembled according to the installation height of the large-sized container 1, and has three rows from the position where it is connected to the cable shooter 2 to a predetermined length (about 3000 m from the center of the container), and the assembly height of the middle row is lowered. It is designed so that the cable can pass through (the upper part of the middle row is shown by a thick solid line in Fig. 1 (b)). After that, one row is connected to the end of the cable passage portion and extends to the cable laying route. 4, 5, 6
Is a stake for lowering the cable to the ground side and connecting to the underground cable laying route. In the case of this embodiment, the three cables can be lowered from different turrets.

In the three-row scaffold portion, the space surrounded by the rows on both sides above the intermediate row is used as a cable passage area, and the rollers 7 are arranged at predetermined intervals. Further, the first wire drawing machine 8 is installed at a position near the container side, and the second wire drawing machine 9 is installed at a position near the wire drawing side. Further, a slack absorbing section 1 is provided before and after the wire drawing machines 8 and 9. The middle row portion of the scaffold portion in the slack absorbing section 1 is made lower than the front and rear thereof to allow the slack of the cable to be removed. The rollers 7 may be installed between the sides of the scaffold on both sides, and the wire drawing machines 8 and 9 may be installed in the upper part of the middle row.

The first wire drawing machine 8 is an oil rolling wire machine for pulling up a cable with a constant tension, and the second wire drawing machine 9 is an AC servo motor 10 of variable speed.

Reference numeral 11 denotes a container / turntable operation console, which is operated while checking the inside of the container from above. Reference numeral 12 denotes a centralized control stand of the wire drawing machine system, which is operated while monitoring the slack state of the cable in the slack absorption section. For the monitoring, a monitor TV or the like can be installed in the slack absorption section, and centralized monitoring control can be performed at another place.

In the large container 1 system, the cable length 510
About 230 tons at 0 mm, about 3 at container and turntable
It will be 0 tons, and the total of them will be about 260 tons.
This is normally started slowly by the drive motor of the turntable 1a, and it is operated at a speed suitable for the speed of the wire drawing machine 9 (maximum 10 m / min) of the AC servo motor as an appropriate speed (the peripheral speed of the outermost layer of the container). And it is stopped slowly. The speed can be controlled by the volume of the operation console 11. On the other hand, the control of the wire drawing machine system can be performed by the volume of the centralized control stand 12 at once for all the wire drawing machines. Turntable 1a and wire drawing machine 8,
Operation 9 is such that it can be stopped automatically or manually if either of the abnormal signals is output during an emergency stop, with some cooperation.

The large-sized long power cable 13 (hereinafter, simply referred to as a cable) is rotated by driving the turntable 1a of the large-sized container 1 to rotate the cable shooter 2 therein.
And is pulled out onto the scaffold 3 by the first wire drawing machine 8, while moving on the roller 7, a predetermined slack 14 is taken in the slack absorbing space l, and further the wire drawing machine 9 on the base 1
It is moved to the roller above the scaffolding part of the row, and through the selected turret, it is extended to the underground cable laying route.

For the slack of the cable in the slack absorbing section 1, the minimum bending radius R of the cable (R ≧ 25d, d is the outer diameter of the cable) is taken into consideration, and the slack due to its own weight and the slack due to the braking distance of the container are considered. Check and set an appropriate amount of slack. A preferred setting example will be described with reference to FIG. 2. When the slack absorption section length 1 is 10 m, the sag h1: 720 mm due to the weight of the cable is the high level of sag, and the allowable sag h2: 2100 mm obtained from the minimum bending radius. Is a low level. On the other hand, from the braking distance of the container and the amount of sag of the cable, it was confirmed that the amount of sag was 1620 mm when the braking distance was 5000 mm. It was confirmed that if the low level is 2100 mm, the braking distance can be absorbed up to 800 mm.

Rollers are attached to the scaffold at predetermined intervals for the purpose of supporting the cables and smoothing the movement. Especially, in the slack absorbing section, when the length is 10 m, both ends of the rollers and the lowest point of the low level. It is desirable to set the horizontal positions of 750 mm and 1500 mm along the minimum bending radius from both ends to prevent buckling during cable behavior.

While the cable is being extended as described above, it may be necessary to make an emergency stop due to some trouble or other reasons. At that time, the wire drawing machine system can stop immediately with a stop signal (brake distance is almost 0), but the container system with a weight of about 60 tons has an extremely large inertial force even if it receives a stop signal, so it stops immediately. You can't do that, and you can only stop after some braking distance. As a result of the implementation, it was confirmed that a braking distance of 150 mm to 500 mm was required, depending on the winding weight and the brake tightening amount. On the other hand, regarding the wire drawing, first, the container side is slowly started, and at the same time, the cable is pulled up by the hydraulic first wire drawing machine 8 and then the cable 13 sent by the second wire drawing machine 9 is drawn. In the process of laying the wire, in the relationship between the former wire drawing machine 8 and the latter wire drawing machine 9, a slight time delay may occur at the time of start and stop in order not to apply excessive tension to the cable and the wire drawing machine. It is necessary to have somewhere to afford that margin. Furthermore, when it is necessary to change the speed on the wire drawing machine side during cable laying, a cable must have a margin to absorb the time difference from the container side. According to the present invention, in any of the above cases, the change in the slack 14 of the cable is dealt with, and in consideration of the minimum bending radius of the cable, the amount of slack caused by the inertial force and the time difference is checked in advance, and the scaffolding is being performed. In the installed absorption section 1 of 10 m, the shape change of the bow shape corresponds.

In addition, the slack 14 of this embodiment is 10 m in section.
Although one circular arc is formed inside, two or more circular arcs may be formed to secure a necessary amount of slack when the height cannot be sufficiently obtained when constructing a scaffold or the like. In addition, the slack 14 of this embodiment
Is vertical in the traveling direction, but may be horizontal in the horizontal direction depending on conditions.

[0019]

As described above, according to the method for slackening and extending a large-sized long power cable according to the present invention, the large-sized long power cable wound in a large container having a large inertial force can be used as an inertial force. In the method of drawing with a small wire drawing machine, a scaffold is assembled from the side of the large container along the direction of the wire, and the wire drawing machine is attached to the position of the scaffold near the container side and the position near the wire drawing side. , A slack absorption section is provided on the scaffold between the front and rear of the wire drawing machine, and the cable fed out by the rotation of the large container is pulled up onto the scaffold by the wire drawing machine near the container side and a predetermined slack is given in the slack absorption section. After it was held, it was sent out to the laying route by the wire drawing machine near the wire drawing side, so that the cable surplus caused by the braking distance of the large container at the time of emergency stop and the speed of the wire drawing machine Can be accommodated by changing the slack of the cable in the slack absorbing section when the cable tension is changed, thus making it impossible to force a large-sized long power cable wound in a large container. The intended purpose of providing a construction method capable of continuously extending wire while giving slack without giving it is achieved.

Therefore, in the long installation of up to 5000 m, it is possible to install a single strip as it is without interposing a connecting part, and the conventional method requires sandwiching the connecting part every 1000 m at maximum. On the other hand, the construction period is about 1/2
It can be shortened to the above.

[Brief description of drawings]

FIG. 1 shows an embodiment of a method for slackening and extending a large-sized long power cable according to the present invention, in which (a) is a plan view and (b) is
Is a side (front) view.

FIG. 2 is an explanatory view showing a slack condition of the cable in a slack absorbing section in the above construction method.

[Explanation of symbols]

 1 large container 1a turntable 2 cable shooter 3 scaffolding 4, 5, 6 turret 7 roller 8 first wire drawing machine (hydraulic type) 9 second wire drawing machine (with AC servomotor 10) 11 container / turntable Operation console 12 Centralized control console for wire-drawing machine system 13 Large size long power cable 14 Cable slack l Slack absorption section

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] January 10, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

A scaffold 3 is assembled from the installation position of the large container 1 along the extending direction of the cable. The scaffold 3 is assembled according to the installation height of the large-sized container 1, and has three rows from the position where it is connected to the cable shooter 2 to a predetermined length (about 3000 mm from the center of the container), and the assembly height of the middle row is lowered. It is designed so that the cable can be passed through (the upper part of the middle row is shown by a thick solid line in Fig. 1 (b)). After that, one row is connected to the end of the cable passage portion and extends to the cable laying route. 4, 5, 6
Is a stake for lowering the cable to the ground side and connecting to the underground cable laying route. In the case of this embodiment, the three cables can be lowered from different turrets.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction content]

For the slack of the cable in the slack absorbing section l, the slack due to its own weight and the slack due to the braking distance of the container are taken into consideration in consideration of the minimum bending radius R of the cable (R ≧ 25d, d is the outer diameter of the cable). Check and set an appropriate amount of slack. A preferred setting example will be described with reference to FIG. 2. When the slack absorption section length 1 is 10 m, the sag h1: 720 mm due to the weight of the cable is the high level of sag, and the allowable sag h2: 2100 mm obtained from the minimum bending radius. Is a low level. On the other hand, it was confirmed from the braking distance of the container and the hanging amount of the cable that the hanging amount was 1620 mm when the braking distance was 500 mm. It was confirmed that if the low level is 2100 mm, the braking distance can be absorbed up to 800 mm. ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 8, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

While the cable is being extended as described above, it may be necessary to make an emergency stop due to some trouble or other reasons. At that time, the wire drawing machine system can stop immediately with a stop signal (the braking distance is almost 0), but the container system with a weight of about 260 tons has an extremely large inertial force even if it receives a stop signal, so it stops immediately. You can't do that, and you can only stop after some braking distance. As a result of the implementation, it was confirmed that a braking distance of 150 mm to 500 mm was required, depending on the winding weight and the brake tightening amount. On the other hand, regarding the wire drawing, first, the container side is slowly started, and at the same time, the cable is pulled up by the hydraulic first wire drawing machine 8 and then the cable 13 sent by the second wire drawing machine 9 is drawn. In the process of laying the wire, in the relationship between the former wire drawing machine 8 and the latter wire drawing machine 9, a slight time delay occurs at the time of start and stop in order not to give excessive tension to the cable and the wire drawing machine. there is a need to have the margin somewhere is needed. Furthermore, when it is necessary to change the speed on the wire drawing machine side during cable laying, a cable must have a margin to absorb the time difference from the container side. According to the present invention, in any of the above cases, the change in the slack 14 of the cable is taken as a countermeasure, and in consideration of the minimum bending radius of the cable, the amount of slack caused by the inertial force and the time difference is checked in advance,
During the scaffolding, a 10 m laying absorption section 1 corresponds to the change in the shape of the bow. ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 17, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

A scaffold 3 is assembled from the installation position of the large container 1 along the extending direction of the cable. The scaffold 3 is assembled according to the installation height of the large-sized container 1, and has three rows from the position where it is connected to the cable shooter 2 to a predetermined length (about 30000 mm from the center of the container), and the assembling height of the middle row is lowered. It is designed so that the cable can be passed through (the upper part of the middle row is shown by a thick solid line in Fig. 1 (b)). After that, one example extends to the end of the cable passage portion and reaches the cable installation route. 4, 5, 6
Is a stake for lowering the cable to the ground side and connecting to the underground cable laying route. In the case of this embodiment, the three cables can be lowered from different turrets.

Claims (2)

[Claims] 1. A scaffold is assembled from the side of a large-sized container on which a large-sized long power cable is wound and installed on a turntable, along the extending direction of the cable, and the position of the scaffold is closer to the container and closer to the extended line. In addition to installing wire drawing machines at the position of, the slack absorbing section is provided on the scaffold between the front and rear of those wire drawing machines, and the cable that is fed out by the rotation of the large container is pulled up onto the scaffold by the wire drawing machine near the container side. A method for slackening and drawing a large-sized long power cable, which comprises sending a predetermined amount of slack in a slack absorbing section and then sending the slack to a laying route with a wire-drawing machine close to the wire-drawing side. 2. The wire drawing method according to claim 1, wherein a guide roller is arranged along the maximum slack position of the cable in the slack absorbing section.