JP2007250538A - Anticorrosion low corona wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anticorrosion low corona wire capable of effectively preventing leakage of anticorrosion grease, corona discharge and corona noise. <P>SOLUTION: The anticorrosion low corona wire is provided with a strand group composed of a plurality of intertwined strands, and a segment layer arranged inside the strand group and formed by intertwining a plurality of segment strands with one another, and has anticorrosion grease filled in the inside. The anticorrosion low corona wire is characterized in that the segment layer is a layer formed by using the plurality of segment strands each having a recess formed on one side surface and a projecting part formed on the other side surface, and by fitting the recess on the side surface of one-side segment strand of the segment strands adjacent to each other to the protrusion of the side surface of the other-side segment strand thereof. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an anticorrosion low corona electric wire, and more particularly to an anticorrosion low corona electric wire suitable for installation on a house and having reduced corona noise.

  Usually, an overhead transmission line is composed of a plurality of strands in which bare aluminum conductors are twisted. Such an overhead power transmission line has a phenomenon that, when there is rain, raindrops adhere to the strands and corona discharge is generated from the raindrops. This corona discharge causes radio interference near the transmission line. Also, along with this corona discharge, audible sound (corona noise) is generated, causing noise complaints from residents under the transmission line.

  Immediately after the overhead wire, oil at the time of manufacture adheres to the surface, so raindrops are likely to form.However, after the overhead wire, the oil on the surface flows down over time, and the surface of the strand made of aluminum is oxidized. In general, the surface of the electric wire has become more hydrophilic, and moisture due to rain spreads to the surface of the electric wire without becoming granular, and the occurrence of corona discharge is generally gradually reduced.

  However, if there is a gap between the wires in the center of the overhead power transmission line, moisture will enter during rain and will be stored there. Even if water droplets on the surface of the overhead power transmission line disappear, the water stored in the internal gaps exudes to the surface in the form of replenishing it, forming water droplets and causing corona discharge.

  For the purpose of preventing this corona discharge, it has been proposed to fill a non-oil filler between strands (see, for example, Patent Document 1). The oil-based filler has a high viscosity, so it is difficult to fill the inside of the electric wire.

  On the other hand, for overhead power transmission lines installed in corrosive environments near the coast, a method of coating and filling anti-corrosion grease is generally adopted as a countermeasure against corrosion. In the finished electric wire, the inside is filled with anti-corrosion grease. In such an anti-corrosion wire, since the gap is filled with grease, water cannot enter, and therefore, the phenomenon that water oozes out to form water droplets and corona discharge can be prevented. Is also possible.

  In practice, however, rainwater from rain soaks into the anti-corrosion grease, and the grease and rainwater gradually flow onto the wire surface together. Since the grease filled in the electric wire flows out to the surface of the electric wire and remains on the surface of the electric wire, the state where oil remains on the surface of the electric wire continues for a long time. For this reason, water droplets adhere to the surface of the electric wires in the rain, and corona discharge occurs.

In addition, an overhead electric wire (see, for example, Patent Document 2) has been proposed in which a fitting-type segment wire having an uneven fitting portion and fitting a concave portion and a convex portion of an adjacent segment is arranged in the outermost layer. However, this overhead electric wire is not filled with anti-corrosion grease inside, and the purpose of the fitting type segment wire is to maintain the shape of the outermost layer. Accordingly, the fitting type segment wire is not intended to suppress the leakage of the anticorrosive grease and the corona noise.
Japanese Patent Laid-Open No. 10-255554 JP 2001-35260 A

  The present invention has been made under the circumstances as described above, and an object of the present invention is to provide an anticorrosion low corona electric wire that effectively prevents anticorrosion grease seepage, corona discharge, and corona noise.

  In order to solve the above-mentioned problem, a first aspect of the present invention includes a group of strands constituted by a plurality of twisted round strands, and a segment layer obtained by twisting a plurality of segment strands, and a segment An anticorrosion low corona wire having an anticorrosion grease filled inside is provided.

  In such a corrosion-resistant low-corona electric wire, one or more layers of strands composed of a plurality of twisted round strands can be arranged outside the segment layer.

  The 2nd aspect of this invention has the segment layer which twisted the several segment strand in the outermost layer, and the strand group comprised by this strand layer by the multiple twisted round strand In the anticorrosion low corona electric wire with the anticorrosion grease filled therein, the segment layer includes a plurality of segment wires provided with a concave portion on one side surface and a convex portion on the other side surface. Provided is a corrosion-resistant low corona electric wire characterized by being a layer formed by fitting a concave portion on a side surface of one segment strand of a wire and a convex portion on a side surface of the other segment strand.

  As the anti-corrosion grease used for the anti-corrosion low corona electric wire as described above, one containing a water-resistant liquid polymer made of polybutene as a base material can be used.

As polybutene, kinematic viscosity at 40 ° C. is a kinematic viscosity at 30~50000mm ² / s, 100 ℃ can be used is a 20~1000mm ² / s.

  Further, the grease may be a blend of 5 to 50 parts by weight of a thickener and 0.01 to 10 parts by weight of an antioxidant with respect to 100 parts by weight of a water-resistant liquid polymer made of polybutene.

  According to the present invention, by arranging a segment layer in which fitting-type segment wires are twisted together, the contact area between adjacent strands is increased, the gap between segment strands is reduced, and the contact surface is curved. For this reason, it is difficult for rainwater to enter the inside when it rains, and it is possible to prevent the grease filled inside from seeping out. As a result, a large corona discharge and corona noise prevention effect can be obtained.

  In particular, by disposing the segment layer on the inner side of the outermost layer strand group, the outermost layer strand group can be configured by a strand group having a circular cross section with excellent corona resistance. In addition, the segment layer placed inside the outermost strand group can suppress the intrusion of water from the outermost layer into the inside of the electric wire, and can quickly discharge the intruded water. Further, it is possible to improve the water drainage on the surface of the electric wire. As a result, a larger corona discharge and corona noise prevention effect can be obtained.

  The best mode for carrying out the invention will be described below with reference to the drawings.

  FIG. 1 shows a cross section of an anticorrosion low corona wire according to an embodiment of the present invention. The anticorrosion low corona electric wire according to this embodiment is provided with an aluminum stranded wire layer 2 in which aluminum strands having a circular cross section are twisted around a core wire 1 of a steel stranded wire, and the stranded wire layer 2 has a substantially trapezoidal cross section. The segment wire 3 is surrounded by a twisted segment layer 3 and the outside thereof is covered with a strand wire 4 having a circular cross section. The space inside the segment layer 3 of the electric wire is filled with anticorrosion grease 5. The outer side of the segment layer 3 is not filled with anticorrosive grease.

  The aluminum strands constituting the aluminum stranded wire layers 2 and 4 are not limited to aluminum or aluminum alloy, but may be a conductor made of copper or the like or a strand whose surface is a conductor (for example, an aluminum-coated steel wire). .

  FIG. 2A shows a segment wire 11 constituting the segment layer 3, and this segment wire 11 has a trapezoidal cross section and includes a convex fitting portion 12 and a concave fitting portion 13. The convex fitting portion 12 is continuously provided in the longitudinal direction of the wire on one side surface in the circumferential direction of the electric wire having a trapezoidal cross section, and the concave fitting portion 13 is formed on the other side surface in the circumferential direction of the electric wire having a trapezoidal cross section. Are provided continuously in the longitudinal direction. When the segment wire 11 is twisted, the convex fitting portion 12 and the concave fitting portion 13 have a convex fitting portion 12 on one side surface of one adjacent strand and a concave portion on the side surface of the other strand. The fitting part 13 is formed so as to fit together.

  FIG. 2B shows a part of the segment layer 3 in which the convex fitting portion 12 and the concave fitting portion 13 of the segment strand 11 are fitted on the fitting surface 14 and twisted together. The segment wire 11 is a conductor made of an aluminum alloy, copper, or the like or a strand whose surface is a conductor (for example, an aluminum-coated steel wire).

  In this way, the segment strands 11 provided with the convex fitting portions 12 and the concave fitting portions 13 on both side surfaces in the circumferential direction of the electric wire are twisted together outside the aluminum stranded wire layer 2 to form the segment layer 3, thereby twisting. Since the convex fitting portion 12 and the concave fitting portion 13 of the adjacent adjacent strands are fitted to each other on the fitting surface 14, a deviation in the electric wire radial direction of each segment strand 11 is prevented, and the shoulder standing and the line floating are prevented. The prevention effect becomes large. Further, by fitting the convex fitting portion 12 and the concave fitting portion 13 of the adjacent strands, the contact area of the fitting surface 14 between the adjacent strands is increased, and the gap between the segment strands 11 is narrowed. In addition, since the contact fitting surface 14 is curved, it is difficult for rainwater to enter the inside during rain, and it is possible to prevent the grease filled inside from seeping out. In this way, a greater corona discharge prevention effect can be obtained.

  FIG. 3 shows a structure in which the segment layer 3 is arranged around the core wire 1 of the steel stranded wire and the two aluminum stranded wire layers 2 and 4 are arranged outside thereof, according to the second embodiment of the present invention. The cross section of an anticorrosion low corona electric wire is shown. That is, in the anticorrosion low corona electric wire shown in FIG. 1, the aluminum stranded wire layer 2 and the segment layer 3 are replaced. Also by such a structure, the same effect as the anticorrosion low corona electric wire of embodiment shown in FIG. 1 is acquired.

  FIG. 4 shows a structure in which segment layers 3a and 3b are arranged around a core wire 1 of a steel stranded wire, and one aluminum stranded wire layer 4 is arranged outside thereof, according to the third embodiment of the present invention. The cross section of an anticorrosion low corona electric wire is shown. That is, in the anticorrosion low corona electric wire shown in FIG. 1, a segment layer is arranged instead of the aluminum stranded wire layer 2. Also by such a structure, the same effect as the anticorrosion low corona electric wire of embodiment shown in FIG. 1 is acquired.

  FIG. 5 shows an anticorrosion low structure having a structure in which a segment layer 3 is arranged around a core wire 1 of a steel stranded wire and an aluminum stranded wire layer 4 is arranged on the outside thereof according to a fourth embodiment of the present invention. A corona wire is shown. That is, in the anticorrosion low corona wire shown in FIG. 1, the aluminum stranded wire layer 2 is removed. Also by such a structure, the same effect as the anticorrosion low corona electric wire of embodiment shown in FIG. 1 is acquired.

  FIG. 6 shows a structure in which two layers of aluminum stranded wires 2 and 4 are arranged around a core wire 1 of a steel stranded wire and a segment layer 3 is arranged outside thereof, according to a fifth embodiment of the present invention. The cross section of an anticorrosion low corona electric wire is shown. That is, in the anticorrosion low corona electric wire shown in FIG. 1, the aluminum stranded wire layer 4 and the segment layer 3 are replaced. Also by such a structure, the same effect as the anticorrosion low corona electric wire of embodiment shown in FIG. 1 is acquired.

  Hereinafter, the anti-corrosion grease 5 used in the anti-corrosion low corona electric wire according to the embodiment will be described.

  As the anticorrosion grease used for the low corona electric wire according to the present embodiment, one containing a water-resistant liquid polymer made of polybutene as a base material is preferable. In particular, it is preferable that 5 to 50 parts by mass of the thickener and 0.01 to 10 parts by mass of the antioxidant are blended with respect to 100 parts by mass of the base material.

  Polybutene is a liquid low polymer obtained by polymerization of butenes (isobutylene, 1-butene, etc.) and has a hydrocarbon main chain, so it has excellent electrical insulation and chemical stability, It is stable against light and light, and is excellent in water resistance, water repellency, weather resistance, aging resistance and the like. In addition, since it has very few impurities, wax, and volatile oil, it has excellent heat resistance and exhibits a low pour point. By filling it with grease containing this, it is a necessary characteristic for a low corona wire. Heat resistance and cold resistance can be increased. Moreover, it is rich in adhesiveness and adhesiveness, and can sag from the electric wire even at high temperatures.

  Such polybutene can be appropriately selected from commercially available ones. For example, Nisseki Polybutene Series (trade names: HV-15, HV-35, HV-54, HV-110, HV-300, etc., manufactured by Shin Nippon Petrochemical Co., Ltd.), Idemitsu Polybutene Series (trade names: 100H, 300H) 2000H, 35R, 100R, 300R, etc., manufactured by Idemitsu Petrochemical Co., Ltd.), Nissan polybutene series (trade names: 3N, 5N, 10N, etc., manufactured by Nippon Oil & Fats Co., Ltd.), and the like can be suitably used.

The polybutene preferably has a kinematic viscosity at 40 ° C. of 30 to 50000 mm ² / s and a kinematic viscosity at 100 ° C. of ²⁰ to 1000 mm ² / s. If the kinematic viscosity is lower than the lower limit value, after filling and laying the electric wire, heat generation due to energization increases the evaporation of the base material component, which may reduce the corona discharge resistance of the low corona electric wire. Moreover, when kinematic viscosity is higher than an upper limit, it will be inferior to the pumpability and handling of grease, and it exists in the tendency for the filling to an electric wire to become difficult.

  As a base material of the grease used for the low corona electric wire according to the present embodiment, other kinds of oils such as mineral oil (naphthenic and paraffinic) and synthetic oil can be used as long as the main component is the above-mentioned polybutene. What mixed less than 50 mass% can be used. More preferably, it contains 80% by mass or more of polybutene, and more preferably 95% by mass or more of polybutene.

  As the thickener to be blended in the base material, those having a dropping point of grease of 220 ° C. or higher are used from the viewpoints of heat resistance and dripping resistance of the grease. Examples of such thickeners include metal composite soaps, inorganic thickeners such as organic bentonite and silica gel, urea compounds such as polyurea, and polymer thickeners such as polytetrafluoroethylene. Or the mixture of 2 or more types is mentioned.

  Organized bentonite is hydrophobized by adsorbing quaternary ammonium cation salts or the like on the surface of bentonite clay mainly composed of clay minerals such as montmorillonite. That is, it is an intercalation compound formed by the quaternary ammonium cation entering between the layered silicate structures of clay minerals, exhibiting excellent dispersibility in organic solvents, and swells when mixed with a substrate. It exhibits thickening and thixotropic properties.

  When an anionic polymer or a silane-based treatment agent is used as the surface treatment agent for bentonite, it is not suitable as a thickening agent because bentonite is not sufficiently hydrophobized and becomes hydrophilic. However, it is preferable to use a silane-based treatment agent after adsorbing a quaternary ammonium cation or the like to make it hydrophobic.

  The metal composite soap is obtained by combining a metal salt of a long chain fatty acid with a metal salt of another acid such as acetic acid, lactic acid, adipic acid, or dialkyl phosphoric acid. Examples of the metal include lithium, aluminum, calcium, and barium.

  As long-chain fatty acids used for these composite soaps, those having a hydroxyl group in the molecule, such as 12-hydroxystearic acid, are particularly preferable because the thixotropic property of grease can be increased by rolling.

  Each of the above-mentioned thickeners is excellent in heat resistance and water resistance, and has high viscosity, so that a grease having high thixotropic properties can be obtained. For this reason, while being excellent in the application property to an electric wire, it can control dripping after installation, and the heat degradation by the heat_generation | fever at the time of electricity supply, and exhibits the outstanding property as a grease for low corona electric wires. .

  In particular, organic bentonite is particularly preferable because it has an ion exchange action and can adsorb metal ions and the like, and does not react with corrosive substances such as acids and hardly changes in quality or softens.

  The blending ratio of the base material and the thickener is adjusted so that the consistency of the resulting grease is 180 to 340 by blending 5 to 50 parts by weight of the thickener with respect to 100 parts by weight of the base material. Is preferred. When the consistency is less than 180, the obtained grease becomes very hard and the applicability is lowered. On the other hand, if it exceeds 340, the resulting grease softens and tends to flow, which is not preferable.

  In the grease used for the low corona electric wire according to the present embodiment, the antioxidant is within a range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the base material in order to suppress deterioration of the grease due to high temperature thermal oxidation. Added. As the antioxidant, phenol-based, amine-based, phosphorus-based and the like can be used, and phenol-based and amine-based ones are particularly preferable.

Furthermore, other additives such as a metal deactivator, an acid acceptor such as calcium carbonate, and a weathering agent such as carbon may be blended in an appropriate amount as long as the effects of the present invention are not hindered. . Moreover, in order to improve the adhesiveness to an electric wire for the thing whose viscosity of a base material is comparatively low (For example, the kinematic viscosity in 40 degreeC is about 40 mm < ² > / s etc.), a thickener is added to a base material. 5-60 mass parts can be added with respect to 100 mass parts. As the thickener, those having excellent flexibility at low temperatures are preferably used, and examples thereof include petroleum resins such as polyisobutylene, olefin copolymer (OCP), polymethacrylate, and petroleum rosin.

  The grease can be produced by an appropriate method such as a saponification method or a mixing method selected according to the raw material.

  For example, with grease containing metal composite soap as a thickener, oils and metal bases are heated and saponified at normal pressure or under pressure in the base material, and after cooling, various additives are added. After heating according to the above, the mixture is mixed, homogenized by milling, filtered and degassed to produce grease.

  In addition, in the case of grease with organic bentonite as a thickener, put the base material and organic bentonite into a mixing kettle, add a swelling agent such as methanol to swell the organic bentonite, mix, various additives, etc. Is added, heated as necessary, mixed, homogenized by milling, filtered and degassed to produce grease.

  Filling the electric wire (twisted wire) with grease can be performed by twisting a plurality of strands while twisting them while filling the grease between the strands.

  The low-corona electric wire manufactured in this way can be applied to overhead electric wires such as overhead power transmission lines and overhead ground wires, as well as jumper wires and buses in substations.

  Specific examples of the polybutene, which is the main component of the base material for the low corona wire grease described above, include the following.

Polybutene 1: having a kinematic viscosity of 28mm ² / s at 645mm ² / s, 100 ℃ at 40 ° C..

Polybutene 2: having a kinematic viscosity of 220 mm ² / s at 9600mm ² / s, 100 ℃ at 40 ° C..

Polybutene 3: having a kinematic viscosity of 850 mm ² / s at 37000mm ² / s, 100 ℃ at 40 ° C..

Polybutene 4: having a kinematic viscosity of 14 mm ² / s at 205mm ² / s, 100 ℃ at 40 ° C..

Polybutene 5: has a kinematic viscosity of 170000 mm ² / s at 40 ° C. and 3100 mm ² / s at 100 ° C.

Test Example A water resistance test was conducted on grease A containing polybutene and, as a comparative example, rough knee grease (manufactured by Nippon Oil Co., Ltd.) that has been conventionally used for corrosion protection of electric wires. That is, after applying grease on the substrate, water was sprayed on the grease in a shower form, and changes in the residual amount of grease with the passage of the test days were examined. As a result, a result as shown in FIG. 7 was obtained.

  From FIG. 7, the grease according to this example containing polybutene did not change so much after 30 days, whereas the normal anti-corrosion grease had a residual amount of grease after 15 days. It can be seen that is greatly reduced.

Sectional drawing which shows the low corona electric wire which concerns on the 1st Embodiment of this invention. Sectional drawing which takes out and shows a segment element. Sectional drawing which shows the low corona electric wire which concerns on the 2nd Embodiment of this invention. Sectional drawing which shows the low corona electric wire which concerns on the 3rd Embodiment of this invention. Sectional drawing which shows the low corona electric wire which concerns on the 4th Embodiment of this invention. Sectional drawing which shows the low corona electric wire which concerns on the 5th Embodiment of this invention. The characteristic view which compares and shows the water resistance of the grease containing polybutene and normal anti-corrosion grease.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Steel wire, 2, 4 ... Aluminum twisted wire layer, 3, 3a, 3b ... Segment layer, 5 ... Grease, 11 ... Segment strand, 12 ... Convex fitting part, 13 ... Concave fitting part recessed part.

Claims (6)

  An anticorrosion low corona electric wire comprising a strand group composed of a plurality of twisted round strands and a segment layer obtained by twisting a plurality of segment strands, and an anticorrosion grease filled in the segment layer.   The anticorrosion low corona electric wire according to claim 1, wherein at least one layer of strands composed of a plurality of twisted round strands is disposed outside the segment layer.   The outermost layer has a segment layer in which a plurality of segment wires are twisted together, and the inside of the segment layer is provided with a strand group composed of a plurality of twisted round strands, with anticorrosion grease inside In the filled anticorrosion low corona electric wire, the segment layer includes a plurality of segment wires provided with a concave portion on one side surface and provided with a convex portion on the other side surface, and a side surface of one segment wire of an adjacent segment wire. An anticorrosion low corona electric wire, characterized in that it is a layer formed by fitting a concave portion of the other and a convex portion on the side surface of the other segment wire.   The said anticorrosion grease contains the water-resistant liquid polymer which consists of polybutenes as a base material, The anticorrosion low corona electric wire in any one of Claims 1-3 characterized by the above-mentioned. 5. The anticorrosion low corona electric wire according to claim 4, wherein the anticorrosion grease has a kinematic viscosity at 40 ° C. of 30 to 50000 mm ² / s and a kinematic viscosity at 100 ° C. of ²⁰ to 1000 mm ² / s.   5. The grease is obtained by blending 5 to 50 parts by weight of a thickener and 0.01 to 10 parts by weight of an antioxidant with respect to 100 parts by weight of a water-resistant liquid polymer made of polybutene. The anticorrosion low corona wire described in 1.

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