JP3465237B1 - Cable with metal impermeable layer - Google Patents

Abstract

An object of the present invention is to facilitate grounding processing of a metal impermeable layer in a cable with a metal impermeable layer having a shielding layer. SOLUTION: A shielding layer 3 in which a copper tape 3a is wrapped and wound.
And a first metallized tape 12 in which a metal foil 12b is attached to the surface of a base tape 12a such as paper between the metal impermeable layer 5 to which a metal laminate tape 5a is vertically attached, and a back surface of the base tape 13a. Second metal foil 13b bonded
The metallized tape layer 11 is formed by wrapping the metallized tape 13 with the metal foil surfaces facing each other and partially overlapping (part) in a parallel state to form a metallized tape layer 11. The metal water-impervious layer 5 and the shield layer 3 are arranged over the entire length in the longitudinal direction of the cable.
They are electrically connected via the metal foil surfaces of the pair of metallized tapes 12 and 13 (paths of,). Since the shielding layer 3 is always grounded, the metal water shielding layer 5 is grounded, and it is not necessary to ground the metal water shielding layer 5 independently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable with a metal water shield layer having a shield layer, and more particularly to means for grounding the metal water shield layer.

[0002]

2. Description of the Related Art As a high-voltage power cable or a control cable laid in, for example, a petrochemical plant, a cable with a metal water-impervious layer having a metal water-impervious layer in which a metal laminate tape is vertically attached is widely used. When it is necessary to ground the metal impermeable layer in this cable with a metal impermeable layer, a method of vertically inserting a drain wire over the entire length of the cable inside the metal impermeable layer and connecting the end of the drain wire to the ground electrode is a method. is there. This method of using a drain wire is a general method for a control cable.

A cable having a structure in which a shielding layer formed by wrapping a metal tape, for example, a copper tape, on a cable core is formed over the entire length, such as a high-voltage power cable,
In addition to the method of vertically extending the drain wire, between the shielding layer and the metal water blocking layer, a semiconductive tape layer is formed by wrapping the semiconductive tape, and the metal water blocking layer is a semiconductive tape layer. Electrical connection is also made to the shielding layer via the. Cable 1 with a metal water shield layer having a shield layer in Figure 5
A conventional example of is shown. This cable 1 with a metal water-shielding layer comprises, in order from the inside on a cable core 2, a shielding layer 3 formed by wrapping a copper tape 3a, a semiconductive tape layer 4 formed by wrapping a semiconductive tape 4a, and a metal laminate tape. This is a structure in which a metal water-impervious layer 5 is formed by vertically extending 5a, and a rubber or plastic sheath 6 is coated on the outer periphery thereof. Note that the wrap winding means that when the tape is spirally wound around the cylindrical body, the tape is wound so as to partially overlap each other. The illustrated cable 1 is a high voltage power cable and the cable core 2 is, for example, an inner semiconductive layer 2 on a conductor 2a.
b, the insulator 2c, and the outer semiconductive layer 2d are provided in this order. The semi-conductive tape 4a also has a function of a press-winding tape that presses the shielding layer 3. Since the shielding layer 3 is naturally grounded in the cable 1 with the metal water shielding layer, the metal water shielding layer 5 electrically connected to the shielding layer 3 through the semiconductive tape 4 is also grounded. Also for control cables, if there is a shielding layer such as copper tape,
Similarly, a method of providing a semiconductive tape layer can be adopted.

[0004]

By the way, when the metal water-permeable layer 5 is formed by vertically adding the metal laminating tape 5a, as shown in FIG. 3 of the present invention, the metal laminating tape 5a is formed. An overlapping portion 5b is formed on both edges of the.
Therefore, in the cable 1 with a metal water-impervious layer having the above-mentioned shield layer 3, the lower edge 5c of the overlapping portion 5b of the metal water-impervious layer 5 vertically aligned by the thermal expansion and contraction in the radial direction is formed on the lower edge 5c. The copper tape 3a of the shielding layer 3 is repeatedly pressed, and as a result, wrinkles may occur, which may lead to breakage. In the case of a cable with a large conductor size and a cable that is laid in a place where the effect of sunlight is strong and subjected to heat cycle,
This phenomenon is particularly remarkable because the insulator expands and contracts greatly. Then, when the copper tape 3a is broken, the shielding function of the shielding layer 3 is impaired. Further, the electric resistance of the lap portion of the wrapped copper tape 3a has a certain magnitude, and the current flowing through the shielding layer 3 does not necessarily flow linearly in the cable longitudinal direction, and the wrapped copper tape 3a is When the cable 1 is used with one end grounded, a discharge may occur and a ground fault or even a fire may occur if the copper tape 3a is broken.

In the above-mentioned conventional cable 1 with a metal water-impervious layer in which the semi-conductive tape layer 4 is arranged between the shield layer 3 and the metal water-impervious layer 5, since the strength of the semi-conductive tape 4 is weak, the overlapping portion is overlapped. Since the pressing force of 5b is not dispersed but locally concentrates on a part of the copper tape 3a (below the edge 5c of the overlapping portion 5b), the copper tape 3a easily breaks as described above.

[0006] In a cable with a metal water shield layer having a shield layer in which a drain wire is vertically installed, since the drain wire serves as a local protrusion, the pressing force from the metal water shield layer side to the copper tape at the drain wire portion is exerted. Concentration may occur and the copper tape may break. In addition, it is troublesome to vertically install the drain wire as a cable manufacturing process, and there is a drawback that the cost is increased.

The present invention has been made in order to solve the above-mentioned conventional drawbacks, and in a cable with a metal water shield layer having a shield layer, the risk that the metal tape of the shield layer is broken can be reduced as much as possible. Another object of the present invention is to provide a cable with a metal water shield layer, which does not impair the shielding function of the cable even if the metal tape breaks and can easily perform the grounding treatment of the metal water shield layer.

[0008]

In order to solve the above-mentioned problems, the invention of claim 1 comprises at least a shielding layer in order from the inside to the outer periphery of a cable core, a metal water-impervious layer in which a metal laminating tape is vertically added, and a sheath. In a cable with a metal waterproof layer, a first metallized tape obtained by bonding a metal foil to a surface of a base tape made of paper or plastic and a back surface of the base tape made of paper or plastic on the shield layer. A second metallized tape to which a metal foil is attached is lap-wrapped in a parallel state with the metal foil surfaces facing each other and partially overlapped, and the metal water-impervious layer is formed on the metallized tape layer. It is characterized by being formed.

According to a second aspect of the invention, there is provided a cable with a metal water shield layer, which comprises at least a shield layer, a metal water shield layer in which a metal laminate tape is vertically inserted, and a sheath in order from the inside to the outer periphery of the cable core. A metallized tape obtained by laminating a metal foil on both sides of a base tape made of paper or plastic is wrapped around the shielding layer, and the metal water-impervious layer is formed on the metallized tape layer. And

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view showing a cable 1A with a metal waterproof layer according to an embodiment of the present invention, which is applied to a high voltage power cable. This cable 1A with a metal water shield layer has a shield layer 3 in which, for example, a copper tape 3a is wrapped and wrapped around the outer periphery of a cable core 2, a metallized tape layer 11 and a metal laminate tape 5a, which will be described in detail later, are vertically added. The metal water barrier layer 5 is formed, and a rubber or plastic sheath 6 is coated on the metal water barrier layer 5. The cable core 2 has a structure in which an inner semiconductive layer 2b, an insulator 2c, and an outer semiconductive layer 2d are sequentially provided on a conductor 2a.

In the present invention, as described above, the metallized tape layer 11 is formed between the shield layer 3 and the metal water shield layer 5. As shown in detail in FIG. 2, the metallized tape layer 11 includes a first metallized tape 12 in which a metal foil 12b is attached to the surface of a base tape 12a made of paper or plastic on the shielding layer 3. , A second metallized tape 13 in which a metal foil 13b is attached to the back surface of a base tape 13a made of paper or plastic, and the metal foils 12b and 13b face each other and partially overlap (partially overlapped portion). (Indicated by) is wrapped in a parallel state. That is, on the shielding layer 3, two metallized tapes 12 and 13 partially facing each other with their metal foil surfaces facing each other are continuously wound to form a metallized tape layer 11, and a metallized tape layer 11 is formed thereon. Water layer 5
To form. The metallized tapes 12 and 13 are the shielding layer 3
Since it fulfills the function of pressing down, it is not necessary to press down with a separate winding tape.

Paper (including processed paper) is suitable as the base tapes 12a and 13a of the metallized tapes 12 and 13, but plastic may be used. In the case of plastic, polyester, polyethylene, nylon or other plastic tape can be used. Metal foil 12
Aluminum foil is suitable for b and 13b, but copper foil or other metal foil may be used. The thickness of the base tape is
The thickness of the metal foil is, for example, about 0.1 to 0.3 mm, preferably about 0.15 mm (± 0.03 mm).
Although the size of the metallized tape is not particularly limited, for example, the thickness is about 0.15 mm (± 0.05 mm, etc.) and the width is 25 m.
Around m (± 10 mm etc.) is appropriate. Further, the thickness of the metal foil is preferably about 0.012 mm (± 0.002 mm or the like).

In the above cable 1A with a metal water shield layer, the first metallized tape 12 having the metal foil 12b on the outer surface (front surface side) is the metal laminated tape 5 of the metal water shield layer 5.
2 (a portion in FIG. 2) and the second metallized tape 13 having the metal foil 13b on the inner side surface (back surface side) comes into contact with (a portion of) the copper tape 3a of the shielding layer 3 and both metallized. Tape 1
Since the metal foils 12b and 13b are in contact with each other in a part of the overlapped portions 2 and 13, the outer metal water-impervious layer 5 is eventually formed.
And the inner shielding layer 3 are a pair of metallized tapes 12, 13
The metal foils 12b and 13b are electrically connected to each other. That is, the metal water-impervious layer 5 and the shield layer 3 are electrically connected over the entire length in the cable longitudinal direction. Therefore, if the shielding layer 3 is grounded by an appropriate method as usual, the metal impermeable layer 5 will be grounded at the same time, and it is not necessary to separately ground the metallic impermeable layer 5. Therefore, the complexity of the conventional method in which a drain wire is additionally provided vertically for grounding is eliminated, and the cable manufacturing process is simplified.

In the cable 1A with a metal water-impervious layer, the copper tape 3a of the shield layer 3 is thermally expanded and shrunk in the radial direction, so that the copper tape 3a of the metal water-impervious layer 5 extending vertically extends from the edge 5c. When subjected to a pressing force, the rigidity of the metallized tapes 12 and 13 is greater than that of the semi-conductive tape,
This pressing force is dispersed as compared with the case of the semi-conductive tape, and a part of the copper tape 3a (the edge 5c of the overlapping portion 5b is formed).
It is possible to reduce the local concentration of the copper tape 3a), and the risk of the copper tape 3a breaking is slightly reduced. Further, even if the copper tape 3a is broken, the metal water-impervious layer 5 is mechanically strong and does not break, and since the metal water-impermeable layer 5 is grounded by the metallized tape layer 11 over the entire length, the cable The shielding function of is not impaired. Further, for example, a metallized tape obtained by laminating an aluminum foil on a paper tape is cheaper than a semiconductive tape, and thus the cable manufacturing cost can be slightly reduced, which is preferable.

FIG. 4 shows an embodiment of the metallized tape layer 21 in the cable with a metal water-blocking layer according to claim 2, which metallized tape layer 21 is the same as in FIG.
And a metal impermeable layer 5, and is provided between the metal foil 22 on both sides of a base tape 22a made of paper or plastic.
It is formed by wrapping a metallized tape 22 in which b and 22b are bonded together. The metallized tape 22 in which the metal foils 22b are adhered to both surfaces is not covered with the outer metal water-impervious layer 5 through the metal foils 22b on the facing surfaces of the adjacent metallized tapes 22 even if only one is wrapped. The inner shield layer 3 is electrically connected. In this case, by bonding the metal foils on both sides, the cost is higher than the metallized tapes 12 and 13 having only one side described above, but since only one type is required, the workability of the wrap winding work is good.

Although a copper tape is used as the shielding layer 3 in the above embodiment, an aluminum tape or a braid of copper wire may be used. Further, in the embodiment, the case where the invention is applied to the high-voltage power cable has been described, but it is naturally applicable to the control cable with the metal water shield layer having the shield layer. In short, the present invention can be applied to a cable with a metal water shield layer that includes at least a shield layer, a metal water shield layer in which a metal laminate tape is vertically attached, and a sheath in order from the inside to the outer periphery of the cable core.

[0017]

According to the cable with a metal water-impervious layer of claim 1, between the shield layer and the metal water-impervious layer, two pieces of metal foil are attached to one surface of a base tape made of paper or plastic. Since the metallized tape layer was provided by wrapping the metallized tapes with the metal foil surfaces facing each other and partially overlapped with each other, the metallized tape layer was used to provide metal impermeability over the entire length in the cable longitudinal direction. Since the layer and the shielding layer are electrically connected, it is not necessary to perform the grounding treatment of the metal water shielding layer independently. Therefore, the complexity of the conventional method in which a drain wire is additionally provided vertically for grounding is eliminated, and the cable manufacturing process is simplified.

When the copper tape of the shielding layer receives a pressing force from the overlapping portion of the vertically aligned metal water shielding layers due to the thermal expansion and contraction of the cable in the radial direction, the rigidity of the metallized tape is semi-conductive. Since the tape is larger than the tape, the pressing force is dispersed as compared with the case of the semi-conductive tape, local concentration on a part of the copper tape is reduced, and the risk of breaking the copper tape is slightly reduced. Also, even if the copper tape breaks, the metal water-impervious layer does not break because it is mechanically strong, and the metal water-impervious layer is grounded by the metallized tape layer over the entire length, so the cable shielding function is It will not be damaged. Also, metallized tapes are generally cheaper than semi-conductive tapes, which can result in slightly lower cable manufacturing costs.

According to the cable with a metal waterproof layer of claim 2, the metallized tape layer formed by wrapping the metallized tape having metal foils adhered on both sides electrically connects the metal waterproof layer and the shield layer electrically. The same effect as described above is obtained. In this case, the cost of the metallized tape itself is slightly increased by using the metallized tape in which metal foils are attached to both surfaces, but the workability of the wrapping is good.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a cable with a metal waterproof layer according to an embodiment of the present invention.

FIG. 2 is an enlarged vertical cross-sectional view of a main part of the cable with a metal waterproof layer.

FIG. 3 is an enlarged view (however, hatching is omitted) of a main part of the cable with a metal waterproof layer of FIG.

FIG. 4 is an enlarged vertical cross-sectional view of a main part of a cable with a metal waterproof layer according to another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a conventional cable with a metal water blocking layer.

[Explanation of symbols]

1A Cable with metal impermeable layer 2 cable core 3 Shielding layer 3a Copper tape (metal tape) 5 Metal impermeable layer 5a Metal laminating tape 6 sheath 11 Metallized tape layer 12, 13 Metallized tape 12a, 13a base plate 12b, 13b Metal foil 21 Metallized tape layer 22 Metallized tape 22a base plate 22b metal foil

Front page continuation (72) Inventor Tatsuya Murofushi, Fujikura Co., Ltd. 1-5-1 Kiba, Koto-ku, Tokyo (56) References JP 2001-6449 (JP, A) JP 2001-291436 (JP, A) ) JP-A-2002-75072 (JP, A) JP-A-8-45360 (JP, A) JP-A-8-329741 (JP, A) JP-A-10-269860 (JP, A) JP-A-11-339577 (JP, A) Actually open 62-175521 (JP, U) Actually open 3-40720 (JP, U) Actually open 5-11220 (JP, U) Actually open 58-154514 (JP, U) Actual Kai 59-2023 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01B 7/17 H01B 7/282 H01B 9/02 H01B 11/06

Claims (2)

(57) [Claims] 1. A cable with a metal impermeable layer, which comprises at least a shielding layer in order from the inside to the outer periphery of a cable core, a metal impermeable layer in which a metal laminating tape is vertically attached, and a sheath, wherein: A first metallized tape having a metal foil attached to the surface of a base tape made of paper or plastic and a second metallized tape having a metal foil attached to the back surface of a base tape made of paper or plastic, 2. A cable with a metal water-impervious layer, characterized in that the metal foil surfaces are faced to each other and are partially overlapped and wrapped in parallel to form the metal water-impervious layer on the metallized tape layer. 2. A cable with a metal water shield layer, which comprises at least a shield layer, a metal water shield layer in which a metal laminate tape is vertically inserted, and a sheath in order from the inside to the outer periphery of the cable core, wherein the shield layer is provided on the shield layer. A metallized water-impervious layer, characterized in that a metallized tape obtained by laminating metal foils on both sides of a base tape made of paper or plastic is wrapped, and the metal water-impervious layer is formed on the metallized tape layer. With cable.