JPS6187879A - Production of stranded conductor element insulated by coating with copper oxide film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to a copper stranded wire in which cupric oxide (
The present invention relates to a method of manufacturing an insulated conductor having a film formed thereon.

Conventional technology Twisted copper wires used as power cables are made by twisting a large number of wires together and then compressing them to increase the space factor. Due to the skin effect that flows near the surface of the entire line, the power transmission capacity does not increase in proportion to the cross-sectional area. Therefore, in order to increase the power transmission capacity, attempts have been made to provide an insulating layer on the surface of the wires to insulate them from each other.

As a method for manufacturing such insulated conductors, a method is known in which a cupric oxide (Cub) film is formed on the surface of the wire, but such an oxide film is formed on the wire in advance, and then If twisting and compression molding are performed, there is a high possibility that the oxide film will peel off during the tacking process or the compression molding process. Conventionally, therefore, a method has been adopted in which compression-molded copper ms is immersed in an oxidizing solution to oxidize the surface layer of the wire, or preheating is performed to promote oxidation.

Problems to be Solved by the Invention However, sufficient oxidation does not occur simply by immersing stranded copper wire in an oxidizing solution, and since the wires are in close contact with each other due to compression molding, the center layer side It is difficult for the oxidation treatment liquid to enter between the strands of the strands, so in the conventional method, it takes a long time to form a sufficient oxide film, resulting in poor productivity. In addition, in the conventional method, cuprous oxide (C) has poor insulation properties and is difficult to convert into cupric oxide.
LIO) may occur.

In view of the above-mentioned circumstances, the present invention provides a method for producing a copper oxide film strand insulated conductor that uniformly, sufficiently, and quickly forms a cupric oxide film over the entire surface layer of the strands of a stranded copper wire. The purpose is to

Means for Solving the Problems In order to achieve the above object, the present invention provides a mixed aqueous solution of 1 to 10% NaClO2 aqueous solution and 1 to 10% NaOH aqueous solution for compression molded f[Ii. 80～
A step of maintaining the temperature at 105°C and press-fitting it, a step of injecting water vapor or hot water at about 100°C into the copper m-wire to wash and remove the mixed aqueous solution, and a step of putting the washed copper stranded wire in an inert atmosphere. heating to 100-300℃, and 1-10%
This method is characterized by including the step of again press-fitting a mixed aqueous solution of a NaC1o2 aqueous solution and a 1 to 10% Na01-1 aqueous solution into the twisted copper wire.

DETAILED DESCRIPTION OF THE INVENTION The present invention can be applied to #il stranded wires with a high compression ratio, such as copper wire with a space factor of about 90%. ! Lines can be targeted. As in the case of ordinary oxidation treatment, the mm wire is preferably subjected to alkaline degreasing treatment, washing removal of the Si treatment liquid, and draining treatment prior to oxidation treatment.

After performing such preliminary treatment, a first oxidation treatment is performed. The main purpose of this is to generate cupric oxide on the surface of the wire in the outer layer, and the oxidizing agent is a 1-10% NaClO2 aqueous solution and a 1-10%
Using a mixed aqueous solution with an NaOH aqueous solution, the mixed aqueous solution is maintained at 80 to 105°C and press-fitted into the target copper stranded wire.

The operation can be carried out, for example, by placing the mixed aqueous solution in a closed tank and placing #! This is carried out by inserting iam into the closed tank while maintaining its water solubility and pressurizing the inside of the closed tank.

Following the oxidation treatment described above, the stranded copper wire is subjected to a cleaning treatment to remove the mixed aqueous solution. This will be converted into Na Cj! during heating in the next step. The purpose of this is to prevent the decomposition of 02 and the generation of ClO2 gas, the formation and adhesion of NaC1'02 crystals, and furthermore to prevent +trt roughness on the conductor surface. This is done by pressurizing steam or hot water at a temperature of around 10°C into the stranded copper wire. More specifically, a method can be adopted in which a stranded copper wire is inserted into a sealed tank in which steam or hot water is pressurized and sealed while maintaining airtightness or watertightness.

Next, the W4 stranded wire is stranded in an inert atmosphere with a
Heat and raise temperature to ℃. The purpose of this is to promote the oxidation of the strands on the center layer side during the oxidation treatment in the next step. The purpose of heating in an inert atmosphere is to prevent the formation of cuprous oxide due to air oxidation. You can use a high-frequency induction heating device.If you heat the stranded copper wire as described above, the strands will swell with heat and the gaps between the strands will widen, and the gas in the gap will become hot! 11ffi and is discharged to the outside, and in the next process, when it is cooled by the oxidation treatment liquid, it contracts and reduces the pressure. By maintaining the above temperature until the next process, the strands between the strands in the center layer are The penetration of the oxidation treatment liquid is improved, and the oxidation reaction is promoted due to the high temperature.

Furthermore, if the heating temperature is 200° C. or higher, an annealing effect is produced, so that work hardening caused by compression molding can be corrected, and the electrical conductivity of the strands, particularly on the center layer side, can be increased and the electrical resistance thereof can be reduced.

The copper stranded wire heated to an elevated temperature as described above is sent to a second oxidation step and subjected to a smelting treatment while maintaining the same temperature. This second oxidation step is mainly aimed at oxidizing the strands on the center layer side, and its conditions and operations are the same as those of the first oxidation treatment step described above. This is carried out by press-fitting a mixed aqueous solution of a CJ202 aqueous solution and a 1-10% NaOH aqueous solution into a stranded copper wire while maintaining the temperature at 80-105°C.

In addition, in this second oxidation treatment step, since the copper stranded wire is heated in the previous stage, the center FF4 is heated as described above.
The mixed aqueous solution as the oxidation treatment liquid easily penetrates into the gaps between the strands of the image, and the oxidation reaction proceeds rapidly. As a result, in the first saponification treatment step, the strands of the outer part are In addition to being oxidized, the surface of the strands of the entire copper frame is oxidized almost uniformly to form a film of cupric oxide.

In addition,! In the process, the mixed aqueous solution is removed by washing with water, and the stranded copper wire is drained and dried, and then wound up. In addition, the above-mentioned series of processing is performed on F, which has been compression-molded in advance.
[This is done while letting the ff out of the drum and running it.
R Continuous treatment is preferred, and for that purpose, the aforementioned closed tanks for oxidation treatment, closed tanks for cleaning, or heating equipment are arranged in sequence, and the target copper stranded wire is inserted into the closed tanks or the equipment. Just let it run. Furthermore, the f! The four-stranded wire itself may be an nn product, or may be a segment in which a plurality of wires are combined to form one conductor.

Effects of the Invention As is clear from the above explanation, according to the method of the present invention, although the oxidation reaction is carried out at a relatively high temperature, there is no room for the production of cuprous oxide due to air oxidation, and moreover, the heating step is not required. It promotes the penetration of the oxidation treatment liquid into the center side and the oxidation reaction, so the strands of the entire compression-molded W4 strand are uniformly oxidized and the cupric oxide film is sufficiently and quickly formed. can be generated.

Claims (1)

[Claims] 1 to 10% (weight%,
Same below) NaClO_2 aqueous solution and 1-10% NaOH
A mixed aqueous solution with an aqueous solution is maintained at 80 to 105°C and then press-fitted, steam or hot water at about 100°C is press-fitted into the copper strands for cleaning, and then the copper strands are placed in an inert atmosphere. Heating to 100-300℃, and then adding 1-10% NaClO_2 aqueous solution and 1-10% NaClO_2 aqueous solution to the heated copper stranded wire.
% NaOH aqueous solution is maintained at 80 to 105°C and press-fitted.