JP2023182998A - Cable track, power cable, and cable track manufacturing method - Google Patents

Abstract

To stably suppress the axial movement of a power cable.SOLUTION: A cable track includes a pipe buried underground, a trough buried underground and connected to the pipe, and a power cable installed continuously in the pipe and the trough, and the power cable is laid bent in an S-shape within the trough, and the trough except for the power cable is filled with a filler.SELECTED DRAWING: Figure 1A

Description

The present disclosure relates to cable lines, power cables, and methods of manufacturing cable lines.

If the conduit where the power cable is laid is installed at a shallow depth underground, the conduit may bend due to the passage of vehicles on the ground, causing the power cable to move in the direction of travel of the vehicle. Sometimes it happened. Such a phenomenon is called "surf riding phenomenon."

Until now, various types of cable lines have been studied in order to suppress the wave riding phenomenon as described above (for example, Patent Document 1).

Utility Model Publication No. 61-159832

An object of the present disclosure is to stably suppress axial movement of a power cable.

According to one aspect of the present disclosure,
pipes buried underground,
a trough buried underground and connected to the pipe;
a power cable continuously laid within the conduit and the trough;
Equipped with
The power cable is bent and laid in an S-shape within the trough,
A cable track filled with a filler is provided in the trough, excluding the power cable.

According to the present disclosure, it is possible to stably suppress movement of the power cable in the axial direction.

FIG. 1A is a schematic horizontal cross-sectional view of a cable line according to an embodiment of the present disclosure. FIG. 1A is a schematic vertical cross-sectional view showing a cable line according to an embodiment of the present disclosure. FIG. 2 is an enlarged schematic horizontal cross-sectional view of the power cable within the trough. FIG. 3 is an enlarged schematic side view of the power cable in the trough according to Modification 1 of the embodiment of the present disclosure. FIG. 4 is a schematic horizontal sectional view showing a cable line according to a second modification of the embodiment of the present disclosure. FIG. 5 is a diagram showing the fixed load relative to the tensile load measured for each of Samples 1 to 4.

[Description of embodiments of the present disclosure]
<Findings obtained by the inventors>
First, the findings obtained by the inventors will be explained.

In conventional cable lines operated by power companies, power cables were laid in sturdy conduits buried deep underground. For this reason, in the conventional cable line, the above-mentioned power cable wave-riding phenomenon is difficult to occur.

On the other hand, in recent years, the use of renewable energy such as wind power generation, which has a small environmental impact, has been promoted.

In cable lines that transmit power from power sources such as wind power generation, power cables are sometimes laid in inexpensive conduits buried shallowly underground to reduce the cost of civil engineering work. . In such a conduit, as described above, the conduit itself bends when a vehicle passes through the conduit, and the cable wave-riding phenomenon tends to occur. When the cable wave-riding phenomenon occurs, there is a risk that the power cable may be abnormally bent inside the manhole and the cable connection portion may be damaged.

In such a case, it is conceivable to install a cable restraint device that mechanically restrains the power cable at the end of the conduit. However, when installing a cable restraint device, it may be difficult to secure an installation space, or sufficient restraint may not be obtained.

Therefore, there has been a need for a cable line that can stably suppress the cable wave-riding phenomenon with a simple configuration.

The present disclosure below is based on the above findings discovered by the present disclosers.

<Embodiments of the present disclosure>
Next, embodiments of the present disclosure will be listed and described.

[1] The cable line according to one aspect of the present disclosure is
pipes buried underground,
a trough buried underground and connected to the pipe;
a power cable continuously laid within the conduit and the trough;
Equipped with
The power cable is bent and laid in an S-shape within the trough,
The trough, excluding the power cable, is filled with a filler.
According to this configuration, movement of the power cable in the axial direction can be stably suppressed.

[2] In the cable line described in [1] above,
The filler includes at least sand.
According to this configuration, the binding force of the power cable can be improved.

[3] In the cable line according to [1] or [2] above,
The filling includes mortar.
According to this configuration, the binding force of the power cable can be stably improved.

[4] In the cable line described in [3] above,
The ratio of the mass of sand to the total mass of mortar in the filling is 70% or more and 98% or less.
According to this configuration, it is possible to stably improve the binding force of the power cable while suppressing damage to the power cable.

[5] In the cable line according to any one of [1] to [4] above,
The power cable has a protrusion within the trough that projects in a radial direction of the power cable.
According to this configuration, the protrusion is engaged with the filling material, and the restraining force of the power cable can be further improved.

[6] In the cable line according to any one of [1] to [5] above,
The power cable does not have a metal sheath.
According to this configuration, the configuration from the conductor of the power cable to the cable sheath is combined as one piece.

[7] A power cable according to still another aspect of the present disclosure,
It is installed on the cable line according to any one of [1] to [6] above.
According to this configuration, movement of the power cable in the axial direction can be stably suppressed.

[8] A method for manufacturing a cable line according to still another aspect of the present disclosure,
The process of installing underground pipes,
installing a trough underground and connecting the trough to the conduit;
Continuously laying power cables within the conduit and the trough;
burying the conduit and the trough underground;
Equipped with
In the step of laying the power cable,
The power cable is bent and laid in an S-shape within the trough,
A filler is filled into the trough excluding the power cable.
According to this configuration, movement of the power cable in the axial direction can be stably suppressed.

[Details of embodiments of the present disclosure]
Next, one embodiment of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to these examples, but is indicated by the scope of the claims, and is intended to include all changes within the meaning and scope equivalent to the scope of the claims.

<One embodiment of the present disclosure>
(1) Cable Line A schematic configuration of a cable line 10 according to an embodiment of the present disclosure will be described with reference to FIGS. 1A to 2. Note that in FIG. 1A, a part of the bending mode of the power cable 100 is omitted.

As shown in FIGS. 1A and 1B, the cable line 10 of this embodiment includes, for example, a power cable 100, a conduit 300, a trough 400, and a manhole 500.

Note that in the following, the "axial direction" of the power cable 100, etc. refers to the direction along the central axis of the power cable 100, etc., and can be paraphrased as the longitudinal direction or extending direction of the power cable 100, etc. Further, the "radial direction" of the power cable 100 etc. refers to a direction perpendicular to the axial direction of the power cable 100 etc., and can be translated as the lateral direction of the power cable 100 etc. in some cases. Furthermore, the term "the direction in which the power cable 100 is laid" refers to the direction in which the power cable 100 is laid on the cable line 20, and can also be translated as the direction in which the power cable 100 extends.

[Power cable]
The power cable 100 shown in FIGS. 1A and 1B is configured as a solid insulated cable (CV cable: crosslinked polyethylene (PE) insulated vinyl sheathed cable, also referred to as XLPE cable) that is a high voltage power transmission cable.

The power cable 100 is configured as an underground cable, for example, and includes a conductor, a cable inner semiconducting layer, a cable insulation layer, a cable outer semiconducting layer, a cable metal shielding layer, and a cable sheath from the central axis of the conductor to the power cable 100. They are arranged in this order toward the outer periphery.

In this embodiment, power cable 100 does not have a metal sheath. The cable metal shielding layer mentioned above is, for example, a metal jacket or a wrapped layer of copper wire or copper tape. The cable sheath contains resin. The conductor-to-cable sheath structure of power cable 100 is joined together as one piece.

For example, the power cable 100 is continuously installed inside a conduit 300, a trough 400, and a manhole 500.

[Pipe line]
The conduit 300 is, for example, buried underground. The conduit 300 is configured as, for example, a cylindrical tube, and contains, for example, resin. Examples of the resin constituting the conduit 300 include FRP (Fiber Reinforced Plastics).

Note that the pipe line 300 is not filled with a filler to be described later. That is, the power cable 100 is laid within the gap of the conduit 300.

[trough]
The trough 400 is, for example, buried underground and connected to the conduit 300. In this embodiment, the trough 400 is provided between the conduit 300 and the manhole 500.

In this embodiment, the trough 400 has a frame (numerals not shown). The frame that constitutes the trough 400 is, for example, a so-called concrete pit. Such a robust frame can protect the power cable 100 within the trough 400.

In this embodiment, the trough 400 is filled with a filler 420. The configuration inside the trough 400 will be described in detail later.

[manhole]
The manhole 500 is, for example, buried underground and connected to the conduit 300 via the trough 400 as described above. A connecting portion (junction box) 200 for the power cable 100 is installed inside the manhole 500 . Furthermore, within the manhole 500, between the connection portion 200 and the trough 400, for example, the power cable 100 is bent in an S-shape (in the vertical direction) to form a so-called offset portion 240.

Note that the manhole 500 is not filled with a filler to be described later. That is, the power cable 100 and its connecting portion 200 are installed within the gap of the manhole 500.

(2) Configuration inside the trough The configuration inside the trough 400 of this embodiment will be described with reference to FIGS. 1A to 2.

As shown in FIGS. 1A and 1B, the power cable 100 is laid, for example, bent in an S-shape within a trough 400. For example, the power cable 100 is bent in an S-shape in at least one of the horizontal direction and the vertical direction. Note that the power cable 100 may be bent in a spiral shape. In this embodiment, the power cable 100 is bent in an S-shape in the horizontal direction, for example. Note that, in the following, a portion of the S-shaped line that is bent into an arc shape may be referred to as a "bent portion BP."

Further, in this embodiment, the trough 400 excluding the power cable 100 is filled with a filler 420 so as to maintain the S-shaped linear shape of the power cable 100. Thereby, the power cable 100 can be restrained.

In this embodiment, the trough 400 has a frame body, and the frame body except for the power cable 100 is filled with a filler 420. The frame that constitutes the trough 400 can suppress rainwater from entering the trough 400. As a result, the linearity of the power cable 100 can be stably maintained.

In this embodiment, the filler 420 includes, for example, at least sand. Thereby, the filler 420 can be easily and densely filled so as to follow a complicated linear shape, such as the inner part of the S-shaped bent portion of the power cable 100. As a result, the linearity of the power cable 100 can be stably fixed within the trough 400, and the binding force of the power cable 100 can be improved.

Further, in this embodiment, the filling 420 includes, for example, mortar. Mortar as filling 420 is in direct contact with power cable 100 . "Mortar" here is a material containing fine aggregate (sand) and cement. Mortar as the filling material 420 is filled into the trough 400 in a water-containing state, and then dried and solidified. Examples of the cement in the mortar include ordinary Portland cement specified by JIS R5210. When the filler 420 contains mortar as described above, collapse of the filler 420 can be suppressed and the binding force of the power cable 100 can be further improved.

The ratio of the mass of sand to the total mass of mortar in the filling 420 (mass percent content) is, for example, 70% or more and 98% or less. Note that the "mass of mortar" used to calculate the ratio here is the mass of mortar after drying. By setting the proportion of sand to 70% or more, it is possible to suppress damage to the power cable 100 caused by excessive restraint of the mortar. On the other hand, by setting the proportion of sand to 98% or less, the binding force of the power cable 100 can be stably improved.

Alternatively, the ratio of the mass of sand to the total mass of mortar in the filling 420 may be, for example, 90% or more and 95% or less. By setting the proportion of sand to 90% or more and 95% or less, it is possible to stably improve the binding force of the power cable 100 described above, and to make the filling 420 containing mortar easy to break. Thereby, even after the filling 420 including mortar has hardened, the filling 420 can be broken and the power cable 100 inside the trough 400 can be taken out. As a result, maintenance of the cable line 20 can be easily performed.

Here, with reference to FIG. 2, the reduction in the axial force of the power cable 100 due to the S-shaped linear shape of the power cable 100 within the trough 400 will be described. Note that the "axial force" here refers to the force for moving the power cable 100 in the axial direction, and can be translated into wave riding force, pulling force, etc.

In FIG. 2, the bending portions BP of the power cable 100 bent into an S-shape are provided at n locations (where n is an integer of 1 or more). The axial force Fs of the power cable 100 reduced by the area where the power cable 100 is bent in an S-shape (hereinafter also referred to as the bending area) is determined by the following Rinfenburg equation (1).

Fs=Fm・exp(-μθ)...(1)

However, Fm is an axial force that moves the power cable 100 from left to right in the axial direction of the power cable 100 on the right (front stage) of the S-shaped bending region of the power cable 100. Fs is an axial force (axial force after reduction) that moves the power cable 100 from left to right in the axial direction of the power cable 100 on the left side (later stage) of the S-shaped bending area of the power cable 100. be. μ is the coefficient of friction between the power cable 100 and the filling 420.

θn is the bending angle (center angle of the circular arc) of the power cable 100 at the n-th bending portion BP. θ is the total angle obtained by adding up the bending angles of the power cable 100 at all bending portions BP, and is determined by the following formula.
θ=Σθn

In the present embodiment, the friction coefficient μ calculated using the Rinfenburg equation (1) in the S-shaped bending region of the power cable 100 within the trough 400 is, for example, 0.3 or more, or 0.5 or more. It may be. Thereby, the axial force Fs of the power cable 100 on the downstream side can be stably reduced by the S-shaped bending region of the power cable 100.

Further, in the present embodiment, the reduction rate Fs/Fm of the axial force of the power cable 100 on both sides of the S-shaped bending region of the power cable 100 is, for example, 0.25 or less, or 0.04 It may be the following. Thereby, excessive stress can be suppressed from being applied to the connecting portion 200 of the power cable 100 inside the manhole 500.

In addition, when the actually measured Fs with respect to Fm gradually increases in a curved manner, the friction coefficient μ and the reduction rate Fs/ Let us find Fm.

Further, in the present embodiment, the radius of curvature R at the bent portion BP of the power cable 100 bent in an S-shape within the trough 400 is larger than the radius of the conduit 300, for example. Thereby, abnormal bending of the power cable 100 can be stably suppressed while making the radius of curvature R of the power cable 100 at the bent portion BP equal to or greater than the allowable bending radius of the power cable 100.

Note that the number n of bent portions BP of the power cable 100 within the trough 400, the length of the bent portion BP in the installation direction of the power cable 100, and the width of the bent portion BP in the direction perpendicular to the installation direction of the power cable 100 are as follows: It is set so as to obtain a desired total angle θ at the bent portion BP of the power cable 100, and is not particularly limited. However, from the viewpoint of shortening the required width and length of the trough 400, the number n of bending portions BP of the power cable 100 within the trough 400 may be, for example, 2 or more and 11 or less. The length of the bent portion BP in the installation direction of the power cable 100 may be, for example, 500 mm or more and 2000 mm or less. When the diameter of the power cable 100 is D, the width of the bent portion BP in the direction perpendicular to the installation direction of the power cable 100 may be, for example, 1D or more and 5D or less.

(3) Cable line manufacturing method (cable laying method)
Next, a method for manufacturing a cable line according to this embodiment will be described with reference to FIGS. 1A and 1B.

The method for manufacturing the cable line 10 of this embodiment includes, for example, a preparation step S10, an installation step S20, a cable laying step S30, and a burying step S40.

(S10: Preparation process)
First, the power cable 100 that constitutes the cable line 10, the conduit 300, the frame that constitutes the trough 400, and the filler 420 are prepared. When the filling material 420 includes mortar, the mortar as the filling material 420 contains a predetermined amount of water.

(S20: Installation process)
After the preparation step S10 is completed, the conduit 300, trough 400, and manhole 500 are installed underground. At this time, a trough 400 is connected to the conduit 300, and a manhole 500 is connected to the conduit 300 via the trough 400.

(S30: Cable installation process)
After the installation step S20 is completed, the power cable 100 is continuously installed inside the conduit 300, the trough 400, and the manhole 500.

At this time, in this embodiment, the power cable 100 is bent in an S-shape within the trough 400 and laid, and the trough 400 excluding the power cable 100 is filled with the filler 420. When the filling 420 includes mortar, the mortar as the filling 420 is dried and solidified. This restrains the power cable 100.

(S40: Burying process)
When the cable installation step S30 is completed, the lid of the frame that constitutes the trough 400 is closed, and the conduit 300 and the trough 400 are covered with earth and sand. Thereby, the pipe line 300 and the trough 400 are buried underground.

Through the above steps, the cable line 10 of this embodiment is manufactured.

(4) Effects of this embodiment According to this embodiment, one or more of the following effects can be achieved.

(a) In the present embodiment, the power cable 100 is laid in an S-shape bent within the trough 400. The inside of the trough 400 excluding the power cable 100 is filled with a filling 420. Thereby, a frictional force can be generated between the entire outer peripheral surface of the power cable 100 and the filler 420. Further, the inside of the S-shaped bent portion BP of the power cable 100 is supported by the filler 420, so that the S-shaped linear shape of the power cable 100 can be maintained. These allow the power cable 100 to be restrained. As a result, it becomes possible to stably suppress the movement of the power cable 100 in the axial direction, that is, the wave riding phenomenon of the power cable 100.

(b) In this embodiment, the power cable 100 can be restrained simply by filling the filler 420 into the trough 400 by utilizing the S-shaped linear shape of the power cable 100.

Thereby, for example, a mechanical cable restraint device can be made unnecessary, and the power cable 100 can be restrained with a simple configuration.

Moreover, this makes it unnecessary to fill the conduit 300 with a filler. As a result, compared to the technique of Patent Document 1 in which pentonite is spread over the entire pipe, in this embodiment, the work process can be shortened and an increase in member costs can be suppressed.

(c) In this embodiment, the filler 420 contains at least sand. Thereby, the filler 420 can be easily and densely filled so as to follow a complicated linear shape, such as the inner part of the S-shaped bent portion of the power cable 100. As a result, the linearity of the power cable 100 can be stably fixed within the trough 400, and the binding force of the power cable 100 can be improved.

(d) In this embodiment, the filling 420 includes mortar. Thereby, the filling material 420 can be solidified while maintaining the S-shaped linear shape of the power cable 100.

Here, if the filler 420 is made only of sand, when rainwater enters the trough 400, there is a possibility that the water-containing sand serving as the filler 420 will gradually collapse. For this reason, the S-shaped linear shape of the power cable 100 collapses. As a result, the binding force of the power cable 100 may be reduced.

In contrast, in the present embodiment, the filling material 420 includes mortar and is hardened, so that even if rainwater enters the trough 400, collapse of the filling material 420 can be suppressed. That is, it is possible to prevent the S-shaped linear shape of the power cable 100 from collapsing. As a result, the binding force of the power cable 100 can be stably improved.

(e) In this embodiment, the trough 400 is provided between the conduit 300 and the manhole 500. Thereby, the power cable 100 can be restrained at a position close to the manhole 500. For example, it is possible to suppress the power cable 100 from being drawn in toward the conduit 300 and from extending toward the manhole 500. Thereby, stress application to the connecting portion 200 of the power cable 100 inside the manhole 500 can be stably suppressed.

(5) Modifications of an Embodiment The above-described embodiment can be modified as required, as shown in the following modifications. Hereinafter, only elements that are different from the above-described embodiments will be described, and elements that are substantially the same as those described in the above-mentioned embodiments will be given the same reference numerals and their explanations will be omitted.

Modifications 1 and 2 of this embodiment will be described with reference to FIGS. 3 and 4, respectively.

<Modification 1>
As shown in FIG. 3, in Modification 1, the power cable 100 has, for example, a protrusion 190 that protrudes in the radial direction of the power cable 100 within the trough 400. As shown in FIG. The protrusion 190 is formed, for example, by wrapping a resin tape around the outer periphery of the cable sheath.

For example, a plurality of protrusions 190 are provided at predetermined intervals in the axial direction of the power cable 100. The number of protrusions 190 may be, for example, 2 or more and 20 or less in one trough 400.

According to the first modification, since the power cable 100 has the protrusion 190, the protrusion 190 can be locked to the filler 420 in the S-shaped bending region of the power cable 100 in the trough 400. Thereby, the binding force of the power cable 100 can be further improved.

<Modification 2>
As shown in FIG. 4, in the second modification, the trough 400 is provided, for example, at an intermediate position in the axial direction of the conduit 300 between the pair of manholes 500.

According to the second modification, the power cable 100 can be restrained in the trough 400 provided at an intermediate position in the axial direction of the conduit 300. Thereby, the binding force of the power cable 100 can be further improved.

Furthermore, according to the second modification, a plurality of troughs 400 can be provided between a pair of manholes 500. Thereby, the restraining force of the power cable 100 can be increased by the number of troughs 400.

<Other embodiments of the present disclosure>
Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above-described embodiments, and various changes can be made without departing from the gist thereof.

In the above-described embodiment, the case where the sand and mortar as the filler 420 is in direct contact with the power cable 100 has been described, but the present disclosure is not limited to this case. The filling 420 may be a sand bag filled with sand. Thereby, the sand bag serving as the filler 420 can be easily taken in and out of the trough 400. As a result, the maintainability of the cable line 10 can be improved. However, if sand or the like as the filler 420 is in direct contact with the power cable 100 as in the above-described embodiment, the frictional force applied to the power cable 100 can be improved.

Next, examples according to the present disclosure will be described. These examples are examples of the present disclosure, and the present disclosure is not limited by these examples.

(1) Preparation of cable lines Cable lines of Samples 1 to 4 below were prepared. A trough was connected to each cable line conduit. The power cable was bent in an S-shape and laid within the trough. In Samples 1 to 4, the following fillings were filled in the troughs excluding the power cables.

[Common specifications for cable lines]
Power cable diameter: 66.5mm
Pipe diameter: 125mm
Radius of curvature of power cable bend in trough: 952mm
Number of power cable bends in the trough: 4 Length of power cable bends in the installation direction: 1125 mm
Width of the bend in the direction perpendicular to the power cable installation direction: 184 mm

[Trough configuration of sample 1]
Filling: Sand bag Power cable protrusion: None [Trough configuration of sample 2]
Filling: Sand only Power cable protrusions: None [Trough configuration of sample 3]
Filling: mortar (sand mass percentage: 94%)
Power cable protrusion: None [Trough configuration of sample 4]
Filling: mortar (sand mass percentage: 94%)
Power cable protrusion: Yes

(2) Measurement A power cable was pulled from the conduit by a chain block, and a predetermined tensile load was applied. At that time, the fixed load at the stage downstream of the trough was measured using a load cell.

(3) Results As shown in FIG. 5, in samples 1 to 4, the fixed load was smaller than the tensile load. It was found that in Samples 1 to 4, the binding force of the power cable improved in this order.

For each sample, the friction coefficient μ calculated using Rinfenburg's formula (1) and the reduction rate Fs/Fm (fixed load/tensile load) of the axial force of the power cable were as follows.
Sample 1: μ=0.37, Fs/Fm=0.15
Sample 2: μ=0.47, Fs/Fm=0.09
Sample 3: μ=0.72, Fs/Fm=0.03
Sample 4: μ=0.82, Fs/Fm=0.02

As described above, it was confirmed that Samples 1 to 4 could stably suppress the movement of the power cable in the axial direction.

<Additional notes>
Aspects of the present disclosure will be additionally described below.

(Additional note 1)
pipes buried underground,
a trough buried underground and connected to the pipe;
a power cable continuously laid within the conduit and the trough;
Equipped with
The power cable is bent and laid in an S-shape within the trough,
The trough, except for the power cable, is filled with a filler.

(Additional note 2)
The cable line according to appendix 1, wherein the trough excluding the power cable is filled with a filler so as to maintain the S-shaped linearity of the power cable.

(Additional note 3)
The cable line according to appendix 1 or 2, wherein the filling includes at least sand.

(Additional note 4)
The cable line according to any one of Supplementary Notes 1 to 3, wherein the filling includes mortar.

(Appendix 5)
The cable line according to appendix 4, wherein the ratio of the mass of sand to the total mass of mortar in the filling is 70% or more and 98% or less.

(Appendix 6)
The cable line according to appendix 5, wherein the ratio of the mass of sand to the total mass of mortar in the filling is 90% or more and 95% or less.

(Appendix 7)
The cable line according to any one of Supplementary Notes 1 to 6, wherein the power cable has a protrusion that protrudes in the radial direction of the power cable within the trough.

(Appendix 8)
The cable line according to any one of Supplementary notes 1 to 7, wherein a friction coefficient calculated using the Rinfenburg formula in a region where the power cable is bent in an S-shape within the trough is 0.3 or more.

(Appendix 9)
The cable line according to any one of Supplementary Notes 1 to 8, wherein a radius of curvature at a bent portion of the power cable bent in an S-shape within the trough is larger than a radius of the conduit.

(Appendix 10)
The trough has a frame,
The cable line according to any one of Supplementary Notes 1 to 9, wherein the frame body excluding the power cable is filled with the filler.

(Appendix 11)
comprising a manhole in which a connection part of the power cable is installed;
The cable line according to any one of Supplementary notes 1 to 10, wherein the trough is provided between the conduit and the manhole.

(Appendix 12)
The cable line according to any one of Supplementary Notes 1 to 11, wherein the trough is provided at an intermediate position in the axial direction of the conduit.

(Appendix 13)
The cable line according to any one of appendices 1 to 12, wherein the power cable does not have a metal sheath.

(Appendix 14)
A power cable installed on the cable line described in any one of Supplementary Notes 1 to 13.

(Appendix 15)
The process of installing underground pipes,
installing a trough underground and connecting the trough to the conduit;
Continuously laying power cables within the conduit and the trough;
burying the conduit and the trough underground;
Equipped with
In the step of laying the power cable,
The power cable is bent and laid in an S-shape within the trough,
A method for manufacturing a cable line, comprising filling the trough excluding the power cable with a filler.

10 Cable line 100 Power cable 190 Projection 200 Connection portion 240 Offset portion 300 Conduit 400 Trough 420 Filler 500 Manhole BP Bend portion

Claims (8)

pipes buried underground,
a trough buried underground and connected to the pipe;
a power cable continuously laid within the conduit and the trough;
Equipped with
The power cable is bent and laid in an S-shape within the trough,
The trough, excluding the power cable, is filled with a filler. The cable line according to claim 1, wherein the filling includes at least sand. The cable line according to claim 1 or 2, wherein the filling includes mortar. The cable line according to claim 3, wherein the ratio of the mass of sand to the total mass of mortar in the filling is 70% or more and 98% or less. The cable line according to claim 1 or 2, wherein the power cable has a protrusion projecting in the radial direction of the power cable within the trough. The cable line according to claim 1 or 2, wherein the power cable does not have a metal sheath. A power cable laid on the cable line according to claim 1 or 2. The process of installing underground pipes,
installing a trough underground and connecting the trough to the conduit;
Continuously laying power cables within the conduit and the trough;
burying the conduit and the trough underground;
Equipped with
In the step of laying the power cable,
The power cable is bent and laid in an S-shape within the trough,
A method for manufacturing a cable line, comprising filling the trough excluding the power cable with a filler.

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