KR20110098548A - Insulated electric wire - Google Patents

Abstract

The present invention relates to an insulated wire. Electricity transmission according to the present invention, the heat-resistant aluminum alloy conductor layer containing zirconium, surround the outer layer of the heat-resistant aluminum conductor layer, evenly distributes the charge of the heat-resistant aluminum alloy conductor layer, ethylene butyl acrylate is An insulated wire is provided surrounding the periphery of the included heat resistant semiconducting layer and the heat resistant semiconducting layer, the heat resistant insulating layer including medium density polyethylene in the second base resin.

Description

Insulated Wire {INSULATED ELECTRIC WIRE}

The present invention relates to an insulated wire.

Insulated wire is an insulated wire between the surface of each conductor or between each conductor using an insulator suitable for the purpose of use.

Insulated wire is a distribution line from substation to consumer. It is used to transmit electricity in indoor wiring, wiring of electric equipment, and wiring in salt area. The transmission capacity of the insulated wire is determined by the type and cross-sectional area of the conductor used in the insulated wire. As the insulated wire used in overhead distribution line, the aluminum coated steel core crosslinked polyethylene insulated wire (ACSR / AW-OC) is mainly used.

In the case of ACSR / AW-OC, the continuous allowable temperature is limited to 90 ° C.

As described above, in the case of an insulated wire that is generally used by the continuous allowable temperature limited to 90 ° C., the transmission capacity is limited.

A method for increasing the transmission capacity of an insulated wire is to use copper having a larger transmission capacity than aluminum instead of aluminum used in the conductor layer. However, copper is not suitable for overhead insulated wire because it is heavier and more expensive than aluminum.

Another method for increasing the transmission capacity of an insulated wire is to increase the power transmission capacity by increasing the cross-sectional area of the insulated wire. However, if the cross-sectional area of the insulated wire is increased, the power transmission capacity can be increased, but there are limitations such as an increase in wind pressure load. For this reason, ACSR / AW-OC of up to 160 mm2 is generally used for overhead distribution lines.

Another way to increase the transmission capacity of an insulated wire is to increase the continuous allowable temperature of the insulated wire. Since conductors used for insulated wires have their own resistance, heat is generated when current flows. That is, as the amount of current flowing through the insulated wire increases, the heat generated in the conductor also increases. When the insulated wire exceeds the allowable continuous temperature, the tensile strength of the conductor is broken and the insulated wire is stretched. At this time, due to the continuously increasing temperature of the insulated wire, the insulated wire continues to increase and breaks without maintaining its own weight. In addition, the insulator used as the covering of the insulated wire also transfers the heat of the conductor so that the temperature rises, and when the temperature exceeds a certain temperature, the insulator is cut off.

The present invention provides an insulated wire having improved heat resistance.

In addition, the present invention is to provide an insulated wire having increased transmission capacity by improving heat resistance.

According to an aspect of the present invention, the heat distribution of the heat-resistant aluminum alloy conductor layer, the heat-resistant aluminum alloy conductor layer containing zirconium, the heat-resistant aluminum alloy conductor layer, which transmits electricity and evenly, the ethylene butyl to the first base resin An insulated wire including a heat resistant semiconducting layer including acrylate and a heat resistant insulating layer including medium density polyethylene in a second base resin, which is formed on the outside of the heat resistant semiconducting layer, is provided.

The heat resistant semiconducting layer may further include low density polyethylene as the first base resin.

The heat resistant semiconductive layer may further include any one or more of carbon black, a crosslinking agent, an antioxidant, and a processing aid.

The heat resistant semiconducting layer may be composed of 100 parts by weight of the first base resin, 40 to 80 parts by weight of carbon black, 1 to 10 parts by weight of crosslinking agent, 0.2 to 5 parts by weight of antioxidant and 1 to 10 parts by weight of processing aid. have.

The heat resistant insulating layer may further include any one or more of carbon black, a crosslinking agent, an antioxidant, and a processing aid.

Heat-resistant insulating layer. The second base resin may further include low density polyethylene.

The heat resistant insulating layer may be composed of 100 parts by weight of the second base resin, 0.5 to 5 parts by weight of carbon black, 1 to 5 parts by weight of crosslinking agent, 0.1 to 3 parts by weight of antioxidant and 0.5 to 5 parts by weight of crosslinking aid. have.

The heat resistant insulating layer may be composed of 100 parts by weight of the second base resin and 0.1 to 15 parts by weight of the second additive.

The second base resin may be composed of 70 to 100 parts by weight of medium density polyethylene, 30 parts by weight or less of low density polyethylene.

The crosslinking agent may be a peroxide crosslinking agent.

It may further include an aluminum-clad steel core layer located in the center of the aluminum alloy conductor layer.

According to the embodiment of the present invention, there is an effect that can improve the heat resistance of the insulated wire.

In addition, according to the embodiment of the present invention, there is an effect that can increase the transmission capacity by improving the heat resistance of the insulated wire.

1 is an exemplary view showing an insulated wire according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description.

Hereinafter, the insulated wire according to the present invention will be described in detail with reference to the accompanying drawings, in the description with reference to the accompanying drawings, the same or corresponding components are given the same reference numerals and redundant description thereof will be omitted. Shall be.

1 is an exemplary view showing an insulated wire according to an embodiment of the present invention.

Referring to FIG. 1, the insulated wire includes an aluminum coated steel core layer 110, a heat resistant aluminum alloy conductor layer 120, a heat resistant semiconducting layer 130, and a heat resistant insulating layer 140.

The aluminum-clad steel core layer 110 is located at the center of the insulated wire. The aluminum-clad steel core layer 110 serves as a support line for supporting the insulated wire load between the pole and the pole. The aluminum coated steel core layer 110 is coated with aluminum on a general steel wire. The aluminum-coated steel core layer 110 is coated with 0.22 mm of aluminum in a general steel wire based on a case where the cross-sectional area of the insulated wire is 160 mm 2, and the continuous allowable temperature can be up to 150 ° C. The temperature of the insulated wire is increased by the heat generated when the current flows in the conductor. At this time, a temperature that the conductor or insulator does not impair the performance of the conductor or the insulator is allowable continuous temperature.

The heat-resistant aluminum alloy (TAL) conductor layer 120 is formed surrounding the outer periphery of the aluminum-clad steel core layer 110. The heat-resistant aluminum alloy conductor layer 120 serves as a converter through which electricity is transmitted. The heat resistant aluminum alloy conductor layer 120 is a conductor layer containing zirconium. The heat-resistant aluminum alloy conductor layer 120 may include 0.05% to 1% zirconium in aluminum. When zirconium is alloyed with less than 0.05% of aluminum, it is not sufficient to improve the heat resistance of the heat-resistant aluminum alloy conductor layer. In addition, when zirconium is alloyed with aluminum in excess of 1%, it is not dispersed in the aluminum alloy, thereby reducing the heat resistance of the heat-resistant aluminum alloy conductor layer. The heat-resistant aluminum alloy conductor layer 120 is an alloy with zirconium, the continuous allowable temperature can be improved up to 150 ℃.

Conductor type Continuous allowable temperature AL 90 ° C TAL 150 ℃

Table 1 shows the continuous allowable temperatures of conductors used in insulated wires.

As can be seen from Table 1, in the case of aluminum used as a conductor layer of most of the conventional insulated wire, the continuous allowable temperature is limited to 90 ° C. However, in the case of the heat-resistant aluminum alloy conductor layer 120 of the embodiment of the present invention, the continuous allowable temperature is 150 ° C. Therefore, the heat-resistant aluminum alloy conductor layer 120 has a higher continuous allowable temperature than the aluminum conductor layer, and thus increases the transmission capacity compared with the conventional art. It can be effected.

The heat resistant semiconducting layer 130 is formed surrounding the outer periphery of the heat resistant aluminum conductor layer 120. The heat resistant semiconducting layer 130 evenly distributes the charge of the heat resistant aluminum alloy conductor layer 120 so that the electric field formed in the heat resistant insulator 140 is uniform. That is, the heat resistant insulator 140 serves to prevent the insulator from being destroyed by excessive stress due to concentration of an electric field.

In addition, the heat resistant semiconducting layer 130 serves to prevent depression of the heat resistant insulator 140.

The heat resistant semiconducting layer 130 includes a polyethylene base resin. In order to form the heat resistant semiconductive layer 130, an additive may be mixed with the base resin.

According to the embodiment of the present invention, the polyethylene base resin constituting the heat resistant semiconductive layer 130 may be low density polyethylene (LDPE). In this case, ethylene butyl acrylate (EBA) may be further included to improve heat resistance of the heat resistant semiconducting layer 130.

In addition, carbon black, a crosslinking agent, an antioxidant, a processing aid, or the like may be used as an additive mixed in the heat-resistant semiconducting layer 130 base resin.

A crosslinking agent is used to crosslink the base resin of the heat resistant semiconductive layer 130 to improve thermal capability.

Here, the crosslinking agent serves to increase the thermal and mechanical properties by interconnecting the polymers of the base resin. Examples of the crosslinking agent include a sulfur crosslinking agent used for crosslinking of natural rubber rubber and a peroxide crosslinking agent used for crosslinking ethylene (PE) resin. In the embodiment of the present invention, since the base resin of the heat resistant semiconducting layer 130 uses an ethylene resin, a crosslinking agent used in forming the heat resistant semiconducting layer 130 may use a peroxide crosslinking agent having a crosslinking temperature higher than the base resin processing temperature. . For example, the crosslinking agent may be a Trogonox-311 crosslinking agent (Akzo Nobel, The Netherlands) which is a peroxide crosslinking agent having a crosslinking temperature of 156 ° C.

For example, the heat resistant semiconducting layer 130 may include 100 parts by weight of the base resin, 40 to 80 parts by weight of carbon black, 1 to 10 parts by weight of the crosslinking agent, 0.2 to 5 parts by weight of the antioxidant, and 1 to 10 parts by weight of the processing aid. It can be formed by.

In this case, in the case of carbon black, when the amount is less than 40 parts by weight, proper resistance of the heat resistant semiconducting layer 130 may not be obtained. When the carbon black exceeds 80 parts by weight, the workability and mechanical strength of the heat resistant semiconductive layer 130 are lowered.

When the crosslinking agent is less than 1 part by weight, crosslinking is not properly performed when the heat resistant semiconductive layer 130 is formed. When the crosslinking agent exceeds 10 parts by weight, the heat resistant semiconducting layer 130 is overcrosslinked, thereby lowering the elongation rate among mechanical properties.

When the antioxidant is less than 0.2 part by weight, the heat resistance of the heat resistant semiconducting layer 130 at a high temperature is weakened. When the antioxidant exceeds 5 parts by weight, the overcrosslinking efficiency is lowered by an excess of the antioxidant.

If the processing aid exceeds 10 parts by weight of carbon black is not uniformly dispersed, the quality of the heat resistant semiconducting layer 130 is reduced.

By the composition as described above, the heat-resistant semiconducting layer 130 according to the embodiment of the present invention has an improved continuous allowable temperature up to 150 ° C.

The heat resistant insulating layer 140 is formed surrounding the outer periphery of the heat resistant semiconducting layer 130. The heat-resistant insulating layer 140 is to prevent the insulated wire withstands the voltage and the current leaks to the outside. The heat resistant insulating layer 140 serves to ensure the life of the insulated wire by making the insulated wire have weather resistance to ultraviolet rays and the environment.

The heat resistant insulating layer 140 includes a polyethylene base resin. In order to form the heat resistant insulating layer 140, an additive may be mixed with the base resin.

According to an embodiment of the present invention, the base resin constituting the heat resistant insulating layer 140 may be medium density polyethylene (MDPE) to improve heat resistance. However, when only medium density polyethylene is used as the base resin, there may be a case where the additive mixture such as carbon black is not evenly distributed in the base resin. In order to prevent such a case from occurring, low density polyethylene may be mixed with medium density polyethylene so as to evenly distribute the mixture of the additives to the base resin.

In addition, carbon black, a crosslinking agent, an antioxidant, a processing aid, or the like may be used as an additive mixed in the heat resistant insulating layer 140 base resin.

As the crosslinking agent used to form the heat resistant insulating layer 140, a peroxide crosslinking agent having a crosslinking temperature higher than the base resin processing temperature of the heat resistant insulating layer 140 is used. For example, the crosslinking agent may be a Trogonox-311 crosslinking agent (Akzo Nobel, The Netherlands) which is a peroxide crosslinking agent having a crosslinking temperature of 156 ° C.

For example, the heat resistant insulating layer 140 is formed by 100 parts by weight of base resin, 0.5 to 5 parts by weight of carbon black, 1 to 5 parts by weight of crosslinking agent, 0.1 to 3 parts by weight of antioxidant, and 0.5 to 5 parts by weight of crosslinking aid. Can be. The base resin may be formed by mixing 60 to 100 parts by weight of medium density polyethylene and 0 to 40 parts by weight of low density polyethylene.

At this time, when the medium density polyethylene is less than 60 parts by weight, the heat resistance performance of the heat resistant semiconducting layer 140 is lowered, it is not possible to ensure a sufficient tensile strength and elongation at high temperatures, creep properties are also reduced.

When the carbon black is less than 0.5 parts by weight, the heat-resistant insulating layer 140 accelerates the decomposition of the polymer when used for a long time, and the UV blocking effect is reduced. When the carbon black exceeds 5 parts by weight, the withstand voltage performance of the heat resistant insulating layer 140 is reduced.

When the crosslinking agent is less than 1 part by weight, the degree of crosslinking of the heat resistant insulating layer 140 is insufficient, and the mechanical properties are lowered. When the crosslinking agent exceeds 5 parts by weight, the possibility of scorch generation during the production of the insulated wire is high, and the elongation of the heat resistant insulating layer 140 is lowered.

When the antioxidant is less than 0.1 part by weight, the heat resistance performance of the heat resistant insulating layer 140 is weakened. If the antioxidant is more than 3 parts by weight, the overcrosslinking efficiency is lowered by the excess of the antioxidant.

When the crosslinking aid exceeds 5 parts by weight, the elongation of the heat resistant insulating layer 140 and the effect of the antioxidant is lowered.

The additive used for the heat resistant insulating layer 140 includes 0.1 to 15 parts by weight based on 100 parts by weight of the base resin. When the additive is less than 0.1 part by weight, deterioration of the polymer is accelerated when the heat resistant insulating layer 140 is used for a long time. When the additive exceeds 15 parts by weight, the mechanical properties of the heat resistant insulating layer 140 are lowered.

By the composition as described above, the heat-resistant insulating layer 140 according to the embodiment of the present invention has an improved continuous allowable temperature up to 150 ℃.

In order to verify the effect of the insulated wire according to the embodiment of the present invention, the heating aging test was performed on the insulated wire and the existing insulated wire of the present invention.

Table 1 shows the criteria for the heat aging test.

In the case of the insulated wire of the present invention, when it is heated at 158 ± 2 ℃ for 168 hours or more, it is tested whether it has a tensile strength of 80% or more and a residual ratio of elongation. Existing insulated wires are tested to have a tensile strength of 80% or more when they are heated at 120 ± 2 ℃ for more than 120 hours.

International test specifications for the performance testing of insulated wires, including tensile strength, elongation and thickness reduction after heating, vary. This test standard is intended to test the problem that when the conductor is used up to the continuous allowable temperature, the insulator loses tension due to lack of tensile strength, breaks due to lack of elongation, or fails to maintain its shape due to excessive thickness reduction. In the embodiment of the present invention is performed based on the KSC standard to test the performance of the insulated wire.

Test subject Continuous allowable temperature
[° C] Heating temperature
[° C] Heating time
[Hr] Tensile strength and
Elongation remaining Insulated wire according to an embodiment of the present invention 125 158 ± 2 168 80% or more Existing Insulated Wire 90 120 ± 2 120 80% or more

Table 2 is a heat aging test standard of the KSC standard for the heat aging test of the present invention. According to the heat aging test standard of the KSC standard, in order for the insulated wire to have a continuous allowable temperature of 90 ° C, the tensile strength and the elongation remaining rate should be 80% or more when it is heated at 120 ± 2 ° C for 120 hours. In addition, when the insulated wire is heated for 168 hours at a temperature of 158 ± 2 ℃ in order to have a continuous allowable temperature of 125 ℃, the tensile strength and elongation residual ratio should be more than 80%. Therefore, in order for the insulated wire according to the embodiment of the present invention to have an allowable temperature of 125 ° C., the heating aging test criteria of the KSC standard shown in [Table 2] must be satisfied.

When the heating aging test of the insulated wire and the existing insulated wire of the present invention as a reference of [Table 2] can be confirmed the results as shown in [Table 3].

Heat aging test Insulated wire according to an embodiment of the present invention Existing Insulated Wire Before the test 72h 168h 140h 310h Before the test 72h Tensile strength (kgf / cm2) 378 355 321 314 308 226 175 Tensile Strength Retention Rate (%) 100 94 85 83 81 100 77 Elongation (%) 733 733 704 692 742 694 554 Elongation Retention (%) 100 96 94 101 95 100 68

Table 3 shows the results of heating aging test of the insulated wire and the existing insulated wire of the present invention.

As can be seen from Table 3, it can be seen that in the case of the insulated wire of the present invention, the tensile strength residual ratio and the elongation residual ratio are maintained at 80% or more until 310 hours in excess of 168 hours of the test standard at 158 ° C. Can be. These results show that the insulation wire of the present invention satisfies the heat aging test standard of the KSC standard.

In the case of the existing insulated wire, it can be seen that after 72 hours, which is less than 120 hours of the test standard at 90 ° C, the tensile strength residual ratio and the elongation residual ratio deteriorate to 80%. In the case of the insulated wire of the present invention, the heat-aging test at 168 ° C. maintained the tensile strength residual ratio and the elongation residual ratio of 90% or more until 140 hours.

Through such a test, it can be seen that in the case of the insulated wire of the present invention, the tensile strength and the elongation rate are superior to those of the existing wire even though more time was tested at a higher heating temperature than the existing insulated wire.

In order to verify the effect of the insulated wire according to the embodiment of the present invention, the heat deformation test was performed on the insulated wire and the existing insulated wire of the present invention.

Heat deformation test is a test to check the mechanical strength at the continuous allowable temperature of the insulated wire and the existing insulated wire of the present invention. In the heat deformation test, the insulation wire and the existing insulation wire of the present invention were subjected to a pressure of 4 kg at a continuous allowable temperature to measure a thickness reduction rate.

In the case of the heat deformation test, when the pressure of 4kg is applied at the heating temperature of 120 ℃ according to the KSC standard, the thickness reduction rate should be less than 40%.

Test subject Continuous allowable temperature
[° C] Heating temperature
[° C] weight
[kg] Thickness reduction rate [%]
(Standard: 40% or less) Insulated wire of the present invention 125 158 ± 2 4 4.3 Existing Insulated Wire 90 120 ± 2 4 19.4

Table 4 shows the heat deformation test results of the insulated wire and the existing insulated wire of the present invention.

As can be seen in Table 4, in the case of the insulated wire of the present invention, it was confirmed that the thickness of about 4.3% was reduced when 4 kg of pressure was applied at a heating temperature of 150 ° C. higher than 120 ° C. of the KSC standard. Can be.

In Table 4, it was estimated that the existing insulation wires could not endure the heat deformation test using the heating temperature of 158 ° C, and the heating temperature was set according to the KSC standard. As a result, in the case of the existing insulated wire, the thickness of 19.4% was reduced when 4 kg of pressure was applied at 120 ° C.

Thus, from the heat deformation test results shown in Table 4, it can be seen that the insulated wire of the present invention has better performance even though the test was performed at a higher heating temperature than the existing insulated wire.

As a result of the test, the insulation wire of the present invention can be confirmed that the performance is improved by increasing the continuous allowable temperature by more than 36% and the continuous allowable current by more than 37% compared to the existing insulated wire of the same standard.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as set forth in the claims below It will be appreciated that modifications and variations can be made.

110: aluminum coated steel core layer 120: heat-resistant aluminum alloy conductor layer
130: heat resistant semiconducting layer 140: heat resistant insulating layer

Claims (11)

A heat-resistant aluminum alloy conductor layer that transmits electricity and includes zirconium;
A heat-resistant semiconducting layer formed on the outside of the heat-resistant aluminum conductor layer to evenly distribute the charge of the heat-resistant aluminum alloy conductor layer and including ethylene butyl acrylate in the first base resin; And
Insulated wire including a heat-resistant insulating layer containing medium density polyethylene in the second base resin, which is formed on the outside of the heat-resistant semiconducting layer.
The method of claim 1,
The heat resistant semiconducting layer,
Insulated wire further comprising a low density polyethylene as the first base resin.
The method of claim 2,
The heat resistant semiconducting layer,
Insulated wire further comprising a first additive further comprising any one or more of carbon black, crosslinking agent, antioxidant, processing aid.
The method of claim 3,
The heat resistant semiconducting layer
100 parts by weight of the first base resin, 40 to 80 parts by weight of the carbon black, 1 to 10 parts by weight of the crosslinking agent, 0.2 to 5 parts by weight of the antioxidant and 1 to 10 parts by weight of the processing aid Insulated wire.
The method of claim 1,
The heat resistant insulating layer,
Insulated wire further comprising a second additive further comprising any one or more of carbon black, crosslinking agent, antioxidant, processing aid.
The method of claim 5,
The heat resistant insulating layer is.
Insulated wire further comprising a low density polyethylene as the second base resin.
The method of claim 6,
The heat resistant insulating layer is
Insulation composed of 100 parts by weight of the second base resin, 0.5 to 5 parts by weight of the carbon black, 1 to 5 parts by weight of the crosslinking agent, 0.1 to 3 parts by weight of the antioxidant and 0.5 to 5 parts by weight of the crosslinking aid. wire.
The method of claim 5,
The heat resistant insulating layer is
The insulated wire, wherein the second base resin is 100 parts by weight and the second additive is 0.1 to 15 parts by weight.
The method according to claim 7 or 8,
The second base resin is insulated wire composed of 70 to 100 parts by weight of medium density polyethylene, 30 parts by weight or less of low density polyethylene
The method according to claim 3 or 5,
The crosslinking agent,
Insulated wire that is a peroxide crosslinking agent.
The method of claim 1,
Insulated wire further comprising an aluminum-clad steel core layer located in the center of the aluminum alloy conductor layer.

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