JP2590702Y2 - Waterproof shielding composite tape and waterproof type power cable using the same - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-shielding composite tape and a water-shielding type power cable having a water-shielding composite layer made of the water-shielding composite tape.

[0002]

2. Description of the Related Art Generally, a rubber or plastic insulated power cable for a high voltage whose working voltage reaches 6.6 kV is provided on a conductor 51 on an inner semiconductive layer 52 and an insulator layer as shown in FIG. 53, an external semiconductive layer 54, a metal shielding layer 55 made of a copper tape, and a protective sheath layer 56 made of a soft vinyl chloride resin composition or the like are sequentially provided. Normally, the conductor 51, the inner semiconductive layer 52, the insulator layer 53, and the outer semiconductive layer 54 are called a cable core.

In the power cable 50 having such a configuration, the protective sheath layer 55 cannot always completely block water penetration into the inside of the cable. When moisture penetrates into the inside of the cable 50, the water reaches the cable core and the outer semiconductive layer 5
4 or the insulating layer 53. Thereby, a defect such as a so-called water tree is generated in the insulator layer 53.
As a result, it has been a serious cause of deteriorating the electrical characteristics such as the insulation performance of the power cable 50.

In order to effectively prevent the deterioration of the electric characteristics of the power cable due to the infiltration of moisture, the inventors of the present invention first set the insulating layer on the cable core of the power cable. Or, directly above the external semiconductive layer, a metal-plastic laminate tape is vertically wrapped as a water barrier layer, and then wrapped with a semiconductive cloth tape.Further, on the semiconductive cloth tape, a copper tape, We have proposed a water-impervious cable on a core with a protective sheath.
No. 890).

[0005] Separately, a water-impervious layer formed by laminating a plastic tape on at least one side of a metal tape is vertically wrapped directly under the outer sheath of the cable core, and is integrated with the sheath. (See Japanese Utility Model Publication No. 3-3934). In this case, after providing a metal shielding layer of copper tape on the outside of the cable core, via a pressing tape winding layer as necessary,
A water barrier layer and a protective sheath layer are provided.

[0006]

However, each of the above-described water-impermeable cable above the core and the water-impermeable cable below the sheath has a separate metal water-impervious layer and a different metal shield layer. For this reason, the number of manufacturing steps is increased, so that there is a problem that the manufacturing of the cable is troublesome and the cost is increased.

In order to solve such a problem, first,
A copper laminated tape, in which an insulating or conductive plastic film and a copper tape used as a metal water shielding layer are sequentially laminated on a copper tape used as a metal shielding layer, is vertically applied on the cable core. It is possible to do. Next, after the overlapping portion of the copper laminated tape is heat-sealed, a protective sheath is extrusion-coated on the copper laminated tape. In this case, the water shielding layer and the metal shielding layer are made of the same material. However, with such a cable, although there is no particular problem at the time of manufacture, if the cable is repeatedly bent at the time of laying or the like, for example, wrinkles are generated on the copper tape or the overlapped portion is separated. In addition, the edge of the copper tape contacts an adjacent copper tape, or the edge of the copper tape constituting the metal shielding layer contacts the edge of the copper tape constituting the metal waterproof layer, and the copper tape becomes It will be torn. Due to such a defect of the copper tape, the water-shielding property and the shielding property were easily lost, and it was not practical.

[0008] The present invention has been made in view of such a point, and it is possible to easily manufacture the metal water-blocking layer and the metal shielding layer in the same manufacturing process, and to form the metal water-blocking layer and the metal shielding layer. It is an object of the present invention to provide a water-impervious shielding composite tape that can almost completely prevent breakage due to contact with each other and a water-impervious power cable using the same.

[0009]

Means for Solving the Problems The present invention includes a water-impervious metal
Lead foil and copper mesh foil or copper as shielding metal
A water-shielding composite tape characterized in that a plastic layer is provided on at least one surface of a metal laminate obtained by integrating a mesh strip with a heat-resistant resin layer therebetween.

[0010] The present invention is, on the conductor, the inner semiconducting layer, an insulating layer, and the water barrier shielding composite arranged outside the cable core portion formed by sequentially arranging the outer semiconductive layer optionally A water-impermeable power cable, comprising: a water-impervious shielding composite layer made of tape; and a protective sheath layer disposed outside the water-impervious shielding composite layer. Hereinafter, the present invention will be described in more detail.

In the water-shielding composite tape of the present invention, the water-shielding metal is a metal capable of preventing water from penetrating into the cable core. As the water shielding metal, for example, a metal foil having corrosion resistance to water, such as a lead foil or a copper foil, can be used. As the metal foil, for example, 10 to 50
A thin foil of μm can be used. When grounding the water-blocking metal, it may be connected to the shielding metal at the end of the cable.

As the shielding metal, it is preferable to use, for example, a copper mesh strip, a copper mesh foil, or a metal mesh strip or a mesh foil formed by plating these with tin, lead or the like. Because, when the metal mesh strip and the metal mesh foil are used as the metal shielding layer, the flexibility and the folding resistance of the power cable can be remarkably improved. In addition, since the load stress is dispersed, the copper tape used for the metal shielding layer can damage the metal water barrier layer due to the edge of the copper tape, damage to the cable core due to copper tape breakage, and abnormal overheating. Is not going to happen.

Here, the copper mesh strip is, for example, 0.0
It is a braided copper wire or tin-plated wire of 5 to 0.80 mm. The copper mesh foil is, for example, 0.05 to
A copper foil having a thickness of 0.50 mm is mesh-processed in an electrolytic solution.

Examples of such a heat-resistant resin layer in which the water-shielding metal and the shielding metal are tightly integrated and laminated are, for example,
Heat resistant resins such as polyester, polyamide, polyamide imide or polyimide films are preferred. Since these resins have a melting point of 150 ° C. or higher, they are not softened by heat even when the protective sheath layer is extrusion-coated. Further, since the cable has excellent mechanical strength, the cable is not easily broken even when repeatedly bent. The thickness of the heat-resistant resin layer is 10 to
It can be appropriately selected within a range of 80 μm.

[0015] Such a water-shielding metal, a heat-resistant resin layer and a shielding metal are laminated by bonding them with an appropriate adhesive such as a polyester hot-melt adhesive or a polyurethane-based adhesive. You can get the body.

As the plastic layer provided on at least one side of such a metal laminate, either a conductive or an insulating plastic can be selected as necessary. That is, for example, when arranging the water-impervious shielding composite tape on the cable core part, the electric conduction between the inner semiconductive layer, the outer semiconductive layer and the shielding metal from the conductor to the shielding metal is made. By establishing electrical continuity, the potentials in these layers become the same, and the electrical stability is improved. For this reason, in order to ensure electrical conduction between the metal laminate and the outer semiconductive layer of the cable core portion, the metal laminate is disposed directly on the outer semiconductive layer or the cable core portion of the metal laminate is It is preferable to provide a conductive plastic layer on the surface facing the side. On the other hand, as the plastic layer provided on the surface of the metal laminate facing the protective sheath layer,
It is preferable to select an insulating plastic in order to improve insulation, but there is no particular limitation.

The following combinations are conceivable for the impermeable power cable using the impermeable shielding composite tape described above, according to the arrangement order of the impermeable metal and the shielding metal, and the type of plastic layer to be selected. Can be

(I) conductor / inner semiconductive layer / insulator layer / outer semiconductive layer / conductive plastic layer / waterproof metal / heat resistant resin layer / shielding metal / protective sheath layer (II) conductor / inner Semiconductive layer / insulator layer / outer semiconductive layer / water barrier metal / heat resistant resin layer / shielding metal / insulating plastic layer / protective sheath layer (III) conductor / inner semiconductive layer / insulator layer / outer Semiconductive layer / conductive plastic layer / shielding metal / heat resistant resin layer / water shielding metal / protective sheath layer (IV) conductor / inner semiconductive layer / insulator layer / outer semiconductive layer / shielding metal / heat resistant Conductive resin layer / water shielding metal / insulating plastic layer / protective sheath layer (V) conductor / inner semiconductive layer / insulator layer / outer semiconductive layer / conductive plastic layer / shielding metal / heat resistant resin layer / Metal for water barrier / insulating plastic layer / protective sheath layer (VI) conductor / inner semiconductive layer / Insulator layer / External semiconductive layer / Conductive plastic layer / Waterproof metal / Heat-resistant resin layer / Shielding metal / Insulating plastic layer / Protective sheath layer (VII) Conductor / Inner semiconductive layer / Insulator layer / Outer semiconductive layer / conductive plastic layer / waterproof metal / heat resistant resin layer / shielding metal / conductive plastic layer / protective sheath layer After vertically arranging adjacent water-impervious shielding composite tapes on the peripheral surface of the part so that a part of them overlaps, the overlapping part of the water-impervious shielding composite tape is thermocompression-bonded to form a water-impervious shielding composite layer I do. After this, on the peripheral surface of the impermeable shielding composite layer,
For example, a waterproof sheathed power cable can be obtained by extrusion-coating a protective sheath layer made of polyethylene or polyvinyl chloride.

[0019]

[Function] The water impervious shielding composite tape of the present invention is made of metal for water impermeability,
The heat-resistant resin layer and the shielding metal are laminated and integrated by a known lamination technique, and a plastic layer can be disposed on at least one surface of the metal laminate to facilitate production. By arranging the water-impervious shielding composite tape outside the cable core, the metal water-impervious layer and the metal shield-shielding layer can be provided simultaneously in the same step.

Further, in the waterproof power cable of the present invention,
Since the metal water-blocking layer and the metal-blocking layer are prevented from directly contacting with a heat-resistant resin layer with excellent heat resistance and mechanical strength, a relatively thin metal foil is used as the metal-blocking layer. Even when the metal mesh strip or the metal mesh foil is used as the layer, it is possible to prevent the metal foil from being in contact with the metal mesh strip or the metal mesh foil and being damaged.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory view showing a metal laminate constituting the water-shielding composite tape of the present invention. In the figure, 11 is a 100 μm thick lead foil 12 having a thickness of 15 μm as a metal for shielding water, and a copper mesh foil 13 having a thickness of 20 μm as a shielding metal laminated and integrated via a polyester film 14 having a thickness of 50 μm. It is a metal laminate. Between each layer, a polyester hot melt adhesive (trade name: PES120E,
(Toa Gosei Chemical Industry Co., Ltd.).

Further, as another example of the metal laminate, a copper mesh strip may be used as a shielding metal. That is, as shown in FIG. 2, a lead foil 22 having a thickness of 30 μm as a metal for water shielding, and a copper mesh strip 23 formed by braiding a tin-plated copper wire having a diameter of 0.08 mm into a mesh as a metal for shielding. May be laminated with a polyurethane adhesive (trade name: Takenate, manufactured by Takeda Pharmaceutical Co., Ltd.) via a polyamide film 24 having a thickness of 25 μm.

By laminating a plastic layer 31 on at least one side of the metal laminate 11 having such a structure, for example, as shown in FIG. The tape 30 is obtained. As the plastic layer 31, for example, Nac Ace GA
A conductive thermoplastic plastic film such as an adhesive polyolefin resin containing conductive carbon such as -OO4KB (trade name; manufactured by Nippon Unicar Co., Ltd.) can be used. Also, for example, Nac Ace GA-002
(Trade name; manufactured by Nippon Unicar Co., Ltd.), and an insulating thermoplastic plastic film such as an adhesive polyolefin resin containing no conductive carbon can also be used.

The water-shielding composite tape 3 as described above will now be described.
A water-impervious type power cable using No. 0 will be described.

In FIG. 4, reference numeral 41 denotes an inner semiconductive layer 43 made of, for example, an ethylene ethyl acrylate copolymer, for example, an insulator layer 44 made of cross-linked polyethylene, and This is a cable core portion in which an external semiconductive layer 45 made of an acrylate copolymer is sequentially provided. On the peripheral surface of the cable core 41,
The above-mentioned shielding / shielding composite tape 30 is laid in such a manner that a part of the adjacent shielding / shielding composite tape 30 overlaps,
This overlapping portion is thermocompression-bonded to provide a water-shielding composite layer 46. Further, a protective sheath layer 47 formed by, for example, extrusion coating of a polyvinyl chloride resin is formed on the peripheral surface of the water-shielding composite layer 46.

Hereinafter, the results of a test performed to confirm the effect of the water-shielded power cable 40 of the present invention having such a configuration will be described.

Examples 1 to 6 On the outer semiconductive layer of the cable core part used for the 6.6 kV rubber-plastic insulated power cable, a water-impervious shielding composite tape having the structure shown in Table 1 was placed. After a part of the water-shielding composite tape was vertically attached so as to overlap with each other, the overlapping portion was thermocompression-bonded to form a water-shielding composite layer. Next, a protective sheath layer was formed by extrusion-coating a polyvinyl chloride resin on the peripheral surface of the water-shielding composite layer, and a 6.6 kV water-proof rubber-plastic insulated power cable of Examples 1 to 6 was prototyped. . Here, for bonding between the layers of the water-impervious shielding composite tape, for example, a two-component curing agent adhesive for lamination such as Takerac and Takenate (trade name; manufactured by Takeda Pharmaceutical Co., Ltd.) was used.

The 6.6 kV water-blocking rubber / plastic insulated power cable of Examples 1 to 6 thus produced was subjected to bending load (bend) at room temperature (20 ° C.) and to 90 ° C. The state of the metal water shielding layer and the metal shielding layer when a bending load was applied was evaluated. In this bending load test, the prototype cable was placed along a bend plate having a diameter 10 times the finished diameter of the cable, and after bending the bend plate eight times,
The prototype cable was dismantled, and the condition of the metal for water barrier and the metal shielding layer was evaluated. Table 2 shows the results.

[0030]

[Table 1]

COMPARATIVE EXAMPLE 1 A 6.6 kV rubber / plastic insulated power cable has a conductive and
Thermoplastic film (100 μm thick, GA-
004BK), lead foil (50 μm thickness) and conductive / thermoplastic film (100 μm thickness, GA-004
BK) were vertically laminated so that a part of adjacent water-impervious tapes overlapped, and the overlapped portions were heat-sealed. Thereafter, a copper tape (0.1 mm thick) was horizontally wound as a metal shielding layer. A polyvinyl chloride resin was extrusion-coated on the peripheral surface of the metal shielding layer, and a 6.6 kV water-blocking rubber / plastic insulated power cable of Comparative Example 1 was prototyped. With respect to the prototype waterproof cable of Comparative Example 1, the state of the metallic waterproof layer and the metallic shielding layer when a bending load was applied at room temperature and 90 ° C. was evaluated in the same manner as in Examples 1 to 6. The results are shown in Table 2.

COMPARATIVE EXAMPLE 2 A copper tape was horizontally wound as a metal shielding layer on the outer semiconductive layer of the cable core portion used for manufacturing a 6.6 kV rubber-plastic insulated power cable, and then 0.15
A non-woven fabric tape having a thickness of mm was wound. Then, on the peripheral surface of the wound nonwoven fabric tape, a 30 μm thick lead for water-blocking metal,
50 μm thick polyester and Bond First VC (5
0 μm thick) with the lead side facing the cable core and the adjacent tapes partially overlapping each other, and the overlapped portion is thermally fused to form a metal. A water barrier layer was formed. Further, a PVC anticorrosion layer was extrusion-coated on the metal impermeable layer, and 6.6 k of Comparative Example 2 was applied.
A prototype V-water-proof rubber / plastic insulated power cable was manufactured. With respect to the prototype water-impervious cable of Comparative Example 2, the state of the metal water-impervious layer and the metal shield layer when a bending load was applied at room temperature and 90 ° C. was evaluated as in Examples 1 to 6. The results are shown in Table 2.

COMPARATIVE EXAMPLE 3 A conductive / thermoplastic film (100 μm thick, trade name NAC ACE GA-004BK, Nippon Unicar) was formed on an outer semiconductive layer of a cable core used for a 6.6 kV rubber / plastic insulated power cable. (stock)
15 μm thick lead, 50 μm thick polyethylene and 2
A water impervious shielding composite tape formed by sequentially laminating a 0 μm thick copper mesh foil is vertically attached so that a part of the adjacent water impervious shielding composite tape overlaps, and then the overlapped portion is thermocompression-bonded to form a water impervious shield. A composite layer was formed. Next, a protective sheath layer was formed by extrusion-coating a polyvinyl chloride resin on the peripheral surface of the water-shielding composite layer, and a 6.6 kV water-proof rubber-plastic insulated power cable of Comparative Example 3 was prototyped. Comparative Example 3 Prototype
In the same manner as in Examples 1 to 6, the state of the metal water-shielding layer and the metal shielding layer when a bending load was applied at room temperature and 90 ° C. was evaluated. The results are shown in Table 2.

COMPARATIVE EXAMPLE 4 On the outer semiconductive layer of the cable core used in the manufacture of a 6.6 kV rubber-plastic insulated power cable,
−004BK (100 μm thickness), copper tape (0.1 mm
Thickness) and Bond First VC (100 μm thick), followed by extrusion coating with a PVC anticorrosion layer to produce a 6.6 kV rubber-plastic insulated power cable of Comparative Example 4. Example 1 of the prototype cable of Comparative Example 4
6, the state of the metal water shielding layer and the metal shielding layer when a bending load was applied at room temperature and 90 ° C. was evaluated. The results are shown in Table 2.

[0035]

[Table 2]

As is clear from Table 2, the water-impervious cables of Examples 1 to 6 exhibited a bending load test at room temperature.
Even in the bending load test at a high temperature, no change was observed in the metal water shielding layer and the metal shielding layer.

On the other hand, in the waterproof cable of Comparative Example 1, the heat-resistant resin layer was not provided between the lead foil as the metallic waterproof layer and the copper tape as the metallic shielding layer. The lead foil was damaged by the edge of the, and it was observed that the lead foil was cut. Further, the copper tape was broken.

In the cable of Comparative Example 2, a non-woven fabric tape is disposed between a copper tape as a metal shielding layer and a lead foil as a metal water shielding layer. Wrinkles were found, copper tapes were broken, and wrinkles were observed.

In the cable of Comparative Example 3, since the polyethylene disposed between the lead foil and the copper mesh foil constituting the impermeable shielding composite layer was not heat-resistant, no abnormality was observed in the bending load test at room temperature. However, in a bending load test at a high temperature, it was confirmed that the lead foil and the copper mesh foil were in contact with each other and the lead foil was damaged because the resin layer made of polyethylene was softened. In addition, the copper mesh foil was found to be broken.

In the cable of Comparative Example 4, since the copper tape was displaced when the cable was bent, it was confirmed that separation occurred at the overlapped portion and that the adjacent copper tape was cut off by the edge of the copper tape.

[0041]

As is clear from the above description, in the water-shielding composite tape of the present invention, since the water-shielding metal and the shielding metal are laminated and integrated, by using the water-shielding composite tape, A metal water shielding layer and a metal shielding layer can be simultaneously provided in the same step outside the cable core portion. Thereby, the manufacturing process of the water-blocking type power cable is shortened, and the manufacturing cost can be reduced. In addition, in the waterproof cable of the present invention, since the heat-resistant resin layer is provided between the shielding metal and the shielding metal, the shielding metal cuts the shielding metal under various temperature conditions. Can be prevented.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of a metal laminate constituting a water-shielding composite tape of the present invention.

FIG. 2 is an explanatory view showing another example of the metal laminate of the embodiment.

FIG. 3 is an explanatory view showing an example of the water-impervious shielding composite tape of the present invention.

FIG. 4 is an explanatory view showing an example of the water-impermeable power cable of the present invention.

FIG. 5 is an explanatory view showing a conventional power cable.

[Explanation of symbols]

11, 21 ... metal laminate, 12 ... lead foil, 13 ... copper mesh foil, 14 ... polyester film, 23 ... copper mesh strip, 24 ... polyamide film, 30 ... water shielding composite tape, 31 ... plastic layer, 40 ... Water-insulated power cable, 41: cable core, 42: conductor, 43: inner semiconductive layer, 44: insulator layer, 45: outer semiconductive layer, 46 ...
Water impervious shielding composite layer, 47 ... Protective sheath layer.

Claims (2)

(57) [Scope of request for utility model registration] [Claim 1] and the lead foil and the shielding for the metal as a water barrier for the metal
A water-impervious shielding composite tape, wherein a plastic layer is provided on at least one surface of a metal laminate obtained by integrating the above-mentioned copper mesh foil or copper mesh strip via a heat-resistant resin layer. 2. The water-impervious shielding composite according to claim 1, wherein an inner semi-conductive layer, an insulator layer, and an outer semi-conductive layer are arranged on the conductor in that order. A water-impermeable power cable, comprising: a water-impervious shielding composite layer made of a tape; and a protective sheath layer disposed outside the water-impervious shielding composite layer.