JPS5858816A - Cable protecting cover - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention provides protection from external forces for transmission cables that are buried underground and laid on shelves in tunnels, underground tunnels, and public ditches, and are used for transmitting power and communication information. This invention relates to a protective cover that doubles as a conduit and is attached to the outer periphery of a cable to prevent the spread of fire to other areas in the event of self-ignition.

Generally, when laying a transmission cable entirely underground, asbestos pipes, hard vinyl pipes, corrugated polyethylene pipes, and other pipes are installed in advance, a series of pipes are completely formed, and then the cables are installed underground.
A well-known installation method is to form concrete manholes at both ends of the conduit and lead the transmission cable from one manhole to the other manhole. In addition, when laying a transmission cable on a shelf in a tunnel or a common ditch, it is usually installed on the shelf with a cross-sectional dimension of about 2 to 3 m in length and 30 to 60 crn in width and height, as shown in Figure 1. Completely blind rigid structure FRP (fiber reinforced plastic) trough 1
The cables 2 are arranged in advance over the entire length, the cables 2 are drawn into the trough, and after installation, the trough lid 3 is sequentially covered over the entire length.

In the conventional cable construction explained above, the civil engineering work, conduit work, trough arrangement work, etc. prior to cable installation require a great deal of labor, expense, and complete installation time, and the capital investment amount is extremely large. I'm here. In particular, the construction of pipelines and the installation of troughs requires construction over the entire length of the route by sequentially joining short rigid structures, which takes time, and can lead to problems such as incomplete joints and flooding. In practice, various problems arise because the joints may break due to ground deterioration. In addition, in the case of a trough, it is practically impossible to maintain watertight joints in the vertical and circumferential directions, and insulating oil prevents fatigue failure of the metal coating, such as in oil-immersed cables. Furthermore, in the event of oil leakage, the cable may leak into the tunnel, resulting in problems such as an insufficient function as a cable protection storage body.

In view of the above-mentioned points, the present invention has a disaster prevention function against external force and fire from others, has a function to completely prevent the influence on others in the event of self-ignition or oil leakage, and allows all cable installation work to be completed at the same time as the cable is brought in. Therefore, during transportation, it has a flat plate or U-shaped cross section and is completely flexible, allowing for example to be wrapped in a drum, and when attached to the outer circumference of the cable, it is formed into a solid and integral shape like a conduit. This provides a labor-saving cable protection cover that can be used.

The present invention will be explained below with reference to embodiments shown in the drawings.

FIG. 2 is a plan view showing one embodiment of the present invention, and particularly shows a state in which a flat cover is assembled into a cylindrical pipe shape.

In the figure, on the inner surface of the flexible band-like plate 4 which is conduit-shaped and serves as the inner surface 5, there is a vertical protrusion 6 for securing, which maintains a gap around the cable.
7.8.9. ] 0' is assembled into a cylindrical shape, and the longitudinal joints 11 extend along the entire length and are bonded together with adhesive. It can be seen that a groove 12.18 is provided along the seam 11 of the flexible strip plate 4, and a joining fitting 14 having a U-shaped cross section and a length of 20 to 30 m is arranged in this part, and is cut with a tool such as a bench. Caulk and check the seam 11. Since the joining fittings 4 are mainly used to obtain the pressing force during the curing of the adhesive at the seam II, they may be attached at intervals of several squares. The longitudinal protrusions 6 and 10 have an uneven fitting structure on the abutment surface 15, and it is necessary to configure the fitting so that the fitting does not create a difference in level with respect to the cable outer surface imaginary line 16. be.

In addition, in order to improve shape retention against internal and external pressure in the form of a pipe,
On the conduit-like inner surface 5, ribs 17 made of iron wire are installed every few meters in the longitudinal direction. Since the lip 17 is embedded and attached at the longitudinal securing projections 6,7,8,9,10, it will not fall off or shift.

As is clear from the description, the above configuration starts from a flat flexible band plate 4 as a base, on which longitudinal protrusions, lips, etc. for security are formed or embedded. The materials etc. of the flexible strip plate 4 will be explained in order.

The flexible strip plate 4 is made of glass fiber, synthetic fiber woven fabric, rubber laminated with cord or roving as a strength part, a polyurethane sheet, an extrusion molded product of thermoplastic plastic,
Molded products made of fiber-reinforced plastic (FRP) or composites of these materials are used, but in order to have appropriate hardness and flexibility, Kepler (trade name) impregnated with unsaturated polyester as the weft, or whole fibers are used. Using a base fabric made entirely of polyester fibers for the warp and a 2-3 ply uncrosslinked rubber notebook, a long strip of sheet metal is drawn between a cylindrical die and a void/voice while being pressurized and heated. Those obtained by performing complete crosslinking are superior. The formed one has a curved ridge on its cross section. Security elements, such as security longitudinal protrusions 6, 7.8.9. It is made of a material with rubber elasticity such as IOI''i rubber or polyurethane, or thermoplastic plastic. In the figure, it is integrally bonded to the flexible strip plate 4 with adhesive in advance, but
It is not necessarily necessary to make it integrally, and since it is made concentric with the cable outer peripheral imaginary line 16, it is not necessary to make the height of the convex portions the same, and the protective cover may have an elliptical cross section in the final conduit.

The lip 17 for improving shape retention is necessary when the cable is directly buried in the ground and subjected to earth pressure, but is not required when the cable is installed on a shelf in a tunnel or a public ditch. When integrating the security longitudinal protrusions into the flexible band-like plate 4, the ribs 17 are placed between the flexible band-like plate 4 and the security longitudinal protrusions with an appropriate interval according to the width of the band. sandwich and integrate.

When the flexible strip plate 4 is shaped like a conduit, the virtual cable line 16
and holes 18, 19° 20 formed υ in the flexible strip plate 4.
．． In order to use the 211 cable as a longitudinal passage in the event of an oil leak, a passage for water supply in the event of self-ignition of the cable, or a water supply channel for a cooling type cable, not only the seam 11 but also the fitting seam 15 must be glued. It is necessary to bond the entire length with adhesive, and in order to increase the strength against internal pressure, the joining metal fitting 14 is installed with a thick plate over the entire length to increase strength.

However, it is not necessary for materials such as rubber, which do not require internal pressure strength and can be easily bonded in a short time.

When laying a cable line, it is formed to the same length as the single length of the cable (usually several hundred meters), wrapped around a drum and transported to the installation site, and when the cable is pulled in, it is attached vertically to the outer circumference of the cable as it is unwound from the drum. However, it can be installed while being integrally formed into a pipe shape.

Therefore, there is no need for plumbing or auxiliary work such as installing short rigid pipes or l/roughs in advance or attaching covers afterwards, which can significantly shorten the construction time, and the entire length of the pipe is seamless. You can get a protective cover.

Furthermore, according to the present invention, arbitrary holes can be provided around the cable along the entire length in the longitudinal direction, so that this part can be used not only as a buffer band to protect the cable from external forces, but also as a cooling water passage. Since it can be used as a passageway for oil leakage, there is no possibility of oil leaking outside the protective cover, making it effective for constructing pollution-preventing railway lines.

It can also be transported by wrapping it in a drum with a band-shaped plate.
This method is also more efficient than transporting finished pipes and troughs.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of cable storage in a trough in a tunnel or a common ditch. FIG. 2 is a cross-sectional view of one embodiment of the present invention. 4...Flexible strip plate, 6.7.8.9.10...Vertical projection for security, 11... Seam, 12.13...Longitudinal groove, 14... Joining metal fitting, 15... Butt surface due to unevenness, 16... Virtual line of cable outer circumference, 17.
・Reply, 18. +9.20.21...Vacancy.

Claims (4)

[Claims] (1) A protective cover for a cable, characterized in that a flexible band-like plate is wrapped around the outer circumference of the cable via a spacing material, and bonded by longitudinal joint bonding to form an integrated conduit. (2) The flexible strip is made of reinforced plastic or thermoplastic.
The protective cover for a cable according to claim 1, characterized in that it is a molded product made of plastic, rubber with reinforcing cords, polyurethane, or a composite material thereof. (3) The cable protection cover according to claim 1 or 2, characterized in that the longitudinal seam is watertight. (4) A protective cover for a cable according to any one of claims 1 to 3, wherein the insulation material is integrally bonded to the flexible band-like plate.