JPS61277116A - Manufacture of compression copper twisted conductor - 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] [Technical Field of the Invention] The present invention relates to a method for manufacturing a compressed copper stranded wire conductor that has almost no discoloration or black oxide film on the conductor surface, particularly on the inner layer strands, and is suitable as a conductor for outdoor cables. .

[Technical Background of the Invention] Cross-linked polyethylene insulated cables, vinyl chloride insulated cables, polyethylene insulated cables, etc. used outdoors generally use compressed stranded wires as conductors.
During long-term use, black copper oxide is often formed on the surface of the conductor, eventually causing stress corrosion cracking, which has become a serious problem.

This stress corrosion cracking phenomenon is thought to occur when the hard copper strands are subjected to large stress during the manufacturing process, and black copper oxide is formed in areas where this stress remains due to the intrusion of rainwater, etc. There is.

As a method to solve this problem, there is a known method of applying a solution of benzotriazole derivatives in liquid paraffin to the surface of the stranded wire before passing it through a compression die (Japanese Patent Publication No. 57-46170). .

[Problems with Background Art] However, in the above method, (a) processing with a die is performed after coating, so the amount of coating liquid attached to the surface of the conductor is extremely small. (b) Since the copper wire before the compression die rotates at high speed, it causes uneven coating. (c) It is difficult to uniformly penetrate the coating liquid into the inside of the stranded wire.

[Purpose of the Invention] The present invention has been made to eliminate such drawbacks, and even if water enters the inside of the compressed copper stranded wire and undergoes a long heat cycle, dry-wet cycle, etc., the surface of the conductor remains intact. It is an object of the present invention to provide a manufacturing method for easily obtaining a compressed copper stranded wire conductor that does not cause discoloration or the formation of black copper oxide, and therefore does not cause stress corrosion cracking.

[Summary of the Invention] That is, the method for producing a compressed stranded copper wire conductor of the present invention involves heating the stranded wire after passing through a compression die to a temperature of 50 to 10
It is characterized in that it is heated to a temperature of 0°C and its outer periphery is coated with a rust preventive oil in which 0.5 to 5% of a benzotriazole derivative is dissolved.

In the present invention, since the concentration of the benzotriazole derivative in the rust preventive oil is low, it sufficiently penetrates into the compressed conductor, and since the conductor is heated, the reaction sufficiently proceeds on its surface.

In that case, the appropriate heating temperature is 50 to 100°C, since if it exceeds 100°C, thermal deterioration of the rust preventive oil will easily occur.
The atmosphere must be such as boiled water, steam, inert gas, etc. that will not oxidize the conductor surface.

Further, suitable benzotriazole derivatives are those that dissolve in oily solvents such as liquid paraffin, and examples of such derivatives include Thiolite B-10,51 (manufactured by Chiyoda Chemical Research Institute, trade name). A suitable concentration of this benzotriazole derivative in the rust preventive oil is 0.5 to 5%. If the concentration is less than 0.5%, the rust preventive effect will be insufficient, and if it exceeds 5%, the viscosity of the rust preventive oil will increase, making it difficult to penetrate into the compressed conductor. After applying rust preventive oil,
The concentration of the benzotriazole derivative needs to be 0.5% or more and less than 5% to sufficiently react with the heated stranded wire surface.

As an oily solvent for dissolving benzotriazole derivatives, liquid paraffin, bolybdenum, silicone oil, etc. can be used. Any material that can dissolve the triazole derivative can be used. For example, liquid paraffin includes industrial liquid paraffin No. 4, and bolybdenum includes, for example, Nisseki Bolybdenum LV-5,0 (Japanese Manufactured by Sekiyu Co., Ltd.
Product name). These are chemically and thermally stable and hydrophobic, so they contribute to corrosion prevention.

[Embodiments of the invention] Examples of the present invention will be described below.

A compressed conductor made by twisting 19 CU wires with a diameter of 2.0 mmφ and compressing them into a circular shape is heated to 70°C, and a benzotriazole derivative (thiolite B-1051) is applied to the outer periphery of the compressed conductor.
A rust preventive oil containing 3% of the above dissolved in liquid paraffin at an oil temperature of 70°C was applied.

The approximately 100 mm length of this twisted wire was divided into an outer layer wire, an inner layer wire, and a center wire, and each wire was immersed in a 0.05% Na2S solution for 1 minute, and then the state of discoloration on the surface of the wire was observed. .

The results are shown in the table below.

Comparative Example 1 Comparative Example 1 A compressed conductor was manufactured with the same strand structure and rust preventive oil composition as in the example except that rust preventive oil was applied to the stranded wires before compression processing, and the surface condition was observed in the same manner. In this case, the temperature of the twisted wire and the antirust oil is room temperature. The results are shown in the table above.

Comparative Example 2 After compression processing, antirust oil was applied, and the same procedure as in Example was carried out. In this case, the temperature of the compressed conductor and antirust oil is room temperature. The results are shown in the table above.

Comparative Example 3 A compressed conductor having the same structure as in the example was manufactured without applying rust preventive oil, and the same test was conducted. The results are shown in the table above.

[Effect of the invention]

Claims (1)

[Claims] In a method for manufacturing a conductor in which a plurality of hard copper strands are twisted together and then passed through a compression die to be compressed, the stranded wire after passing through the compression die is heated to a temperature of 50 to 1 in a non-oxidizing atmosphere.
A method for producing a compressed stranded copper wire conductor, which comprises heating the conductor to a temperature of 0.000C and applying a rust preventive oil in which 0.5 to 5% of a benzotriazole derivative is dissolved to the outer periphery of the conductor.