JP2000341842A - Wound tape connecting part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wound tape connecting part capable of eliminating an air gap (triangular void or the like) between wound tape layers in the wound tape connecting part of crosslinked polyethylene power cables or at the overlapped part of tapes, thereby increasing the electrical reliability of the wound tape connecting part of the crosslinked polyethylene power cable. SOLUTION: This wound tape connecting part for a crosslinked polyethylene power cable involves an inner semi-conductive tape winding layer 5 on the outer periphery of the conductor connecting part of two crosslinked polyethylene power cables in which terminal crosslinked polyethylene-insulated layer are stripped so that conductors may be exposed, a self-welding insulating tape winding layer on the outer periphery of the inner semi-conductive tape winding layer 5, and an outer semi-conductive tape winding layer on the outer periphery of the self-welding insulating tape winding layer, wherein the self-welding insulating tape winding layer is an alkyl phenyl ketone impregnated self-welding insulating tape winding layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape winding connection. More specifically, the present invention relates to a tape wound connection of a crosslinked polyethylene insulated power cable.

[0002]

2. Description of the Related Art Generally, the length of an insulated electric wire, a power cable, and the like is generally limited due to production facilities, winding devices, transport vehicles, and the like. For this reason, when installing an insulated wire, a power cable, etc. over a long length, those terminal parts are connected. Various methods are used for connecting such insulated wires and power cables depending on their voltage class, type of insulating material, and the like.

[0003] As a connecting portion of a crosslinked polyethylene power cable of 22 to 77 kV class, a tape wound connecting portion is widely used. In this method of constructing the tape winding connection part of the crosslinked polyethylene power cable, first connect the conductors of the crosslinked polyethylene power cable to be connected, and then wind the self-fusing insulating tape around the outer periphery of the connection part between the conductors. To form an electrical insulating layer.

Here, as the self-fusing insulating tape, a self-fusing insulating tape mainly containing EPR (ethylene / propylene rubber) is used.

[0005] In the method of constructing the tape winding connection portion of the cross-linked polyethylene power cable, when the self-fusing insulating tape is wound around the outer periphery of the conductor-to-conductor connection portion, a layer between the winding tapes and the overlap of the tape, etc. Are wound so that no voids (triangular voids or the like) are formed in the holes. This is because void discharge is likely to occur at the tape winding connection portion of the cross-linked polyethylene power cable in which a gap is formed between the winding tape layers or at the tape joint, and as a result, the electrical insulation breakdown occurs at the tape winding connection portion. There is concern.

However, in the actual tape winding connection portion of the cross-linked polyethylene power cable, even if a gap (triangular void or the like) is formed between the winding tape layers or at the overlap portion of the tape at the time of winding, the winding tape is self-contained. Since it is a fusible insulating tape, its self-fusing property and winding tension close the gaps with the passage of time, so that there is no electrical problem.

[0007]

However, in the tape-wound connecting portion of the crosslinked polyethylene power cable, a high voltage is applied before the self-fusing property of the used self-fusing insulating tape and the void eliminating action due to the winding tension occur. There is a concern that a void discharge may occur and a trace of void discharge may remain in the tape winding connection part. Such a void discharge trace in the tape winding connection portion is not preferable because it has a high possibility of becoming a starting point of electrical insulation breakdown.

The present invention has been made in view of such a point, and an object of the present invention is to solve the above-mentioned disadvantages of the prior art, and to provide a method of manufacturing a cross-linked polyethylene power cable in which a tape between tape windings is used. It is an object of the present invention to provide a tape winding connection part in which no voids (triangular voids or the like) are formed in tape overlapping portions or the like, thereby significantly improving the electrical reliability of the tape winding connection part of the crosslinked polyethylene power cable.

[0009]

SUMMARY OF THE INVENTION The gist of the present invention resides in that an inner half is provided on the outer periphery of a conductor connection portion of two crosslinked polyethylene power cables in which a conductor is exposed by peeling off a crosslinked polyethylene insulating coating layer of a terminal. A conductive tape winding layer is provided, and a self-fusing insulating tape winding layer is provided around the inner semiconductive tape winding layer, and the self-fusing insulating tape winding layer is provided. In a tape winding connection portion of a crosslinked polyethylene power cable having an outer semiconductive tape winding layer provided on an outer periphery, the self-fusing insulating tape winding layer is an alkylphenyl ketone-impregnated self-fusing insulating tape winding layer. There is a tape winding connection part.

That is, the present invention provides a tape winding connection portion of a crosslinked polyethylene power cable using an alkylphenyl ketone-impregnated self-fusing insulating tape, so that it is possible to temporarily cover the winding tape between the tape layers and the tape overlap at the time of winding. Even if voids (triangular voids, etc.) are generated, these voids are effectively closed by the action of alkyl phenyl ketone, thereby significantly improving the electrical reliability of the tape wound connection portion of the crosslinked polyethylene power cable. .

In the present invention, the alkyl phenyl ketone includes acetophenone, n-octanophenone, n-octanophenone,
Decanophenone, laurophenone, n-tetradecanophenone, n-hexadecanophenone, n-heptadecanophenone, 4'-n-octylacetophenone, 4-n
Octanoylbiphenyl, 1,9-diphenyl-1,
One or a mixture of two or more selected from 3,6,8-nonatetraen-5-one and 2-isopropoxy-1,2-diphenylethanone is preferable.

In the present invention, the amount of the alkylphenyl ketone impregnated in the wound layer of the self-fusing insulating tape impregnated with alkylphenyl ketone is preferably 1 to 5% by weight.

The reason why the impregnation amount of the alkylphenyl ketone is set to 1 to 5% by weight is that when the amount is less than 1%, the effect of closing the voids is small, and when the amount is more than 5% by weight, dimensional swelling is caused. This is because characteristics, mechanical characteristics, and the like are deteriorated.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a tape winding connection portion of the present invention and a tape winding connection portion of a conventional comparative example will be described.

(Connection Base of Cross-linked Polyethylene Power Cable) First, a connection base of a cross-linked polyethylene power cable used in an embodiment of the tape winding connection section of the present invention and a conventional tape winding connection section of a comparative example will be described.

(Example 1) First, a copper stranded wire conductor was exposed by shaving off a crosslinked polyethylene insulating layer at the ends of two crosslinked polyethylene power cables to be connected.

Next, the copper stranded conductors at the ends of the cross-linked polyethylene power cable having the cross-linked polyethylene insulation layer removed therefrom were brought into axial contact with each other and brought into contact with each other, and then a copper sleeve was fitted around the outer periphery thereof.

Next, an inner semiconductive tape was wrapped around the outer periphery of the copper sleeve several times.

Next, the acetophenone-impregnated self-fusing ethylene / propylene rubber insulating tape was wound many times on the wound layer of the internal semiconductive tape.

The method for preparing the acetophenone-impregnated self-fusing ethylene / propylene rubber insulating tape used here is as follows.

First, a self-fusing ethylene / propylene rubber insulating tape having a thickness of 0.5 mm was prepared, and then immersed in setophenone at room temperature for 3 days.

Next, after dipping for 3 days, the self-fusing ethylene-propylene rubber insulating tape was taken out of the setophenone, and then the self-fusing ethylene-propylene rubber insulating tape was wrapped with aluminum foil.

Next, a self-fusing ethylene / propylene rubber insulating tape whose outer periphery is wrapped in aluminum foil is placed in a constant temperature bath at 60 ° C. and heated to obtain an acetophenone-impregnated self-fusing ethylene / propylene rubber. An insulating tape was obtained. This acetophenone impregnated self-fusing ethylene
The propylene rubber insulating tape impregnated with acetophenone is 2
% By weight.

Next, an external semiconductive tape was wound on the wound layer of the acetophenone-impregnated self-fusing ethylene / propylene rubber insulating tape to obtain a tape wound connection portion of Example 1.

FIG. 1 is a partially sectional front view showing the tape winding connection portion of the first embodiment thus obtained.

In FIG. 1, 1 and 1 'are cross-linked polyethylene power cables, 2' and 2 'are copper stranded conductors, 3 and 3' are cross-linked polyethylene insulation coating layers, 4 is a copper sleeve, and 5 is an inner semiconductive tape wound. Reference numeral 6 denotes a wound layer of an acetophenone-impregnated self-fusing ethylene / propylene rubber insulating tape, and reference numeral 7 denotes an outer semiconductive tape wound layer.

Example 2 In the same manner as in Example 1, the stranded polyethylene insulating layer at the ends of the two crosslinked polyethylene power cables to be connected was scraped off to expose the copper stranded conductor.

Next, the copper stranded conductors at the ends of the crosslinked polyethylene power cable from which the crosslinked polyethylene insulating layer was scraped off were opposed and contacted in the axial direction, and then a copper sleeve was fitted around the outer periphery thereof.

Next, an inner semiconductive tape was wound around the outer periphery of the copper sleeve several times.

Next, a laurophenone-impregnated self-fusing ethylene / propylene rubber insulating tape was wound many times on the wound layer of the above-mentioned internal semiconductive tape.

The method for producing the laurophenone-impregnated self-fusing ethylene / propylene rubber insulating tape used here is as follows.

First, a self-fusing ethylene / propylene rubber insulating tape having a thickness of 0.5 mm was prepared, and then immersed in laurophenone at room temperature for 3 days.

Next, after immersion for 3 days, the self-fusing ethylene-propylene rubber insulating tape was taken out of the laurophenone, and then the self-fusing ethylene-propylene rubber insulating tape was wrapped with aluminum foil.

Next, a self-fusing ethylene-propylene rubber insulating tape whose outer periphery is wrapped in aluminum foil is placed in a constant temperature bath at 60 ° C. and heated to obtain laurophenone-impregnated self-fusing ethylene-propylene. A rubber insulating tape was obtained. This laurophenone impregnated self-fusing ethylene
Laurophenone impregnation amount of propylene rubber insulating tape is 3
% By weight.

Next, an external semiconductive tape was wound on the wound layer of the laurophenone-impregnated self-fusing ethylene / propylene rubber insulating tape to obtain a tape wound connection portion of Example 2. .

Comparative Example 1 In the same manner as in Example 1, the cross-linked polyethylene insulating layer at the ends of the two cross-linked polyethylene power cables to be connected was scraped off to expose the copper stranded conductor.

Next, the copper stranded wire conductors at the ends of the cross-linked polyethylene power cable from which the cross-linked polyethylene insulating layer was scraped off were opposed and contacted in the axial direction, and then a copper sleeve was fitted on the outer periphery thereof.

Next, an inner semiconductive tape was wound around the outer periphery of the copper sleeve several times.

Next, a self-fusing ethylene / propylene rubber insulating tape was wound many times on the wound layer of the internal semiconductive tape.

Next, an external semiconductive tape was wound on the wound layer of the self-fusing ethylene / propylene rubber insulating tape to obtain a tape wound connection portion of Comparative Example 1.

(Test Method) Next, the discharge starting voltage of the tape wound connection of Example 1, the tape wound connection of Example 2, and the tape wound connection of Comparative Example 1 thus obtained was measured by a standard method. .

(Test Results) Table 1 shows the results of these tests.

[0043]

[Table 1]

As can be seen from Table 1, the discharge starting voltage of the tape winding connection portion of Comparative Example 1 is the lowest at 80 kV.

On the other hand, the discharge starting voltage of the tape winding connection portion of Example 1 was remarkably high at 160 kV. Further, the discharge starting voltage of the tape winding connection portion of Example 2 was remarkably high at 140 kV.

The acetophenone-impregnated self-fusing ethylene-propylene rubber insulating tape and laurophenone-impregnated self-fusing ethylene-propylene rubber insulating tape used in Examples 1 and 2 were impregnated with acetophenone or laurophenone in advance. However, in the present invention, the same effect can be obtained by performing the tape winding operation while dripping these liquid components during the self-fusing insulating tape winding operation.

Further, the acetophenone-impregnated self-fusing ethylene / propylene rubber insulating tape and laurophenone-impregnated self-fusing ethylene • used in Examples 1 and 2 were used.
The propylene rubber insulating tape is based on a self-fusing ethylene / propylene rubber insulating tape, but in the present invention, other self-fusing insulating tapes such as a self-fusing silicone rubber tape may be used.

[0048]

The tape winding connection of the present invention has a high discharge starting voltage, thereby exhibiting high reliability in initial and long-term use, and is industrially useful.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional front view showing a tape winding connection portion according to a first embodiment of the present invention.

[Explanation of symbols]

 1, 1 'cross-linked polyethylene power cable 2, 2' copper stranded conductor 3, 3 'cross-linked polyethylene insulating coating layer 4 copper sleeve 5 inner semi-conductive tape winding layer 6 acetophenone impregnated self-fusing insulating tape winding layer 7 External semiconductive tape wound layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H02G 1/14 H02G 1/14 A F term (Reference) 4J004 AA05 AA07 AA17 AB01 BA02 EA01 EA06 FA05 5G305 AA04 AB02 BA13 BA14 BA20 CA01 CA51 CD20 5G333 AA03 AB01 AB23 BA01 BA05 CA01 CC18 DA03 DA11 5G355 AA03 BA02 BA12 CA22 5G375 AA02 BA09 BB45 CA02 CA14 CB03 CB04 CB17 EA17

Claims (3)

[Claims] 1. An internal semiconductive tape winding layer is provided on the outer periphery of a conductor connection portion of two crosslinked polyethylene power cables in which a crosslinked polyethylene insulating coating layer of a terminal is peeled off to expose a conductor, and A self-fusing insulating tape winding layer is provided on the outer periphery of the inner semi-conductive tape winding layer, and an outer semi-conductive tape winding layer is provided on the outer periphery of the self-fusing insulating tape winding layer. In a tape wound connection part of a crosslinked polyethylene power cable, the wound layer of the self-fusing insulating tape is a wound layer of a self-fusing insulating tape impregnated with alkylphenyl ketone. 2. The method of claim 1, wherein the alkyl phenyl ketone is acetophenone, n-octanophenone, n-decanophenone, laurophenone, n-tetradecanophenone, n-hexadecanophenone, n-heptadecanophenone, 4'-. n-
1 selected from octyl acetophenone, 4-n-octanoylbiphenyl, 1,9-diphenyl-1,3,6,8-nonatetraen-5-one and 2-isopropoxy-1,2-diphenylethanone 2. The tape winding connection according to claim 1, wherein the tape winding connection is a seed or a mixture of two or more kinds. 3. The alkylphenyl ketone impregnated self-fusing insulating tape has an alkylphenyl ketone impregnation amount of 1 to 3.
2. The tape winding connection according to claim 1, wherein the content is 5% by weight.