JPH0431026B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a manufacturing method for forming a rust preventive film with excellent corrosion resistance on the surface of a copper wire using benzotriazole. [Prior Art] Conventionally, during the storage of copper wires, copper wires and stranded copper wires, or during the manufacturing process and storage of insulated wires,
The surface of copper wires and copper strands may become discolored. For this reason, copper wires, stranded copper wires, etc. are coated with benzotriazole or/and its derivatives or other anti-rust solutions for copper during various manufacturing processes to perform anti-rust treatment. or,
A black oxide film forms on the surface of the hard copper stranded wire used for outdoor distribution lines several years after the wire is installed, and in rare cases, the hard copper stranded wire breaks in an abnormal knife cut shape, which is called stress corrosion cracking. may occur. Therefore, as a countermeasure, benzotriazole or/and its derivatives are used to prevent the surface of the hard copper stranded wire from being oxidized even if corrosive rainwater (corrosive substances contained in rainwater) enters the wire from the terminal end. It has been proposed to form a rust-preventing film by using Generally, in order to form a rust preventive film on the surface of a copper wire, a 0.5 to 3% rust preventive solution prepared by dissolving benzotriazole or/and its derivatives in a volatile organic solvent or water is poured onto a running copper wire by dripping, flowing, A rust preventive film is formed by spraying or immersing a copper wire in a rust preventive solution, squeezing out the excess solution that adheres to it, and drying it. [Problems to be solved by the invention] However, when a rust preventive solution containing benzotriazole or the like dissolved in a volatile organic solvent such as methyl alcohol is applied to the copper wire and the solvent evaporates, the added benzotriazole or the like becomes solid. precipitation,
A chelate compound with copper is not formed, that is, a rust preventive film is not formed. In addition, since the rust preventive film formed is colorless and transparent, it is not possible to visually determine whether the rust preventive film has been formed reliably from its appearance. Furthermore, if dirt such as oil or fat is attached to the surface of the copper wire, there is a problem that a reliable rust-preventing film cannot be formed even if the above-mentioned rust-preventing solution is applied. Therefore, if the method of applying the anti-corrosion solution is not appropriate, even if the copper wire is subjected to anti-rust treatment, it may discolor in a short period of time if left in a hot and humid atmosphere, or the hard copper stranded wire used for outdoor distribution lines may become discolored in a short period of time. Even if anti-rust treatment is applied to the hard copper strands, it is not possible to form a rust-preventive film on the hard copper strands that can withstand a long-term corrosive environment. The present invention was made in view of the above-mentioned problems, and it is possible to reliably form a strong rust-preventing film with benzotriazole on the surface of copper wire, and to prevent the copper wire from being exposed to nature or immersed in a corrosive aqueous solution. The object of the present invention is to provide a method for manufacturing a corrosion-resistant copper wire that maintains its copper color over a long period of time. [Means for Solving the Problems] As a result of intensive studies to solve the above object, the present inventors have found that after continuous drawing or continuous softening of the copper wire, the copper wire with residual heat is heated. The present invention was completed by discovering that the object can be achieved by passing or repeatedly passing through a rust preventive solution and the vapor atmosphere of the solution. The manufacturing method of the present invention comprises at least 50°C in a container.
In running a copper wire through a three-component rust preventive solution of benzotriazole-water-chlorine solvent heated as described above, the copper wire is passed through or repeatedly held in the vapor atmosphere of the above-mentioned rust preventive solution and the solution. It is characterized by continuously forming a rust-preventing film with benzotriazole on the surface of the running copper wire. The configuration of the present invention will be further explained below. A benzotriazole-water-chlorinated solvent antirust solution is a solution of benzotriazole dissolved in the minimum amount of methyl alcohol that dissolves it, and a mixed solution of water and 1,1,1 trichloroethane (the mixing ratio of water is 10
(preferably in the range of % to 80%).
Preferably, the benzotriazole concentration is in the range of 0.5-3.0% by weight and heating is performed at 50-70°C. By using such a mixed solution of water and 1,1,1 trichloroethane, cleaning the copper wire surface and forming a rust-preventive film on the surface is more efficient than using 1,1,1 trichloroethane alone. can be done. Here, other than 1,1,1 trichloroethane, 1,1,2 trichloroethane, trichloroethylene, etc. can also be used, but 1,1,1 trichloroethane, which has a low boiling point, is more preferable. In addition, benzotriazole derivatives other than benzotriazole, such as benzotriazole monoethanolamine salt, benzotriazole diethylamine salt, benzotriazole cyclohexylamine salt, benzotriazole morpholine salt, benzotriazole diisopropylamine salt, methylbenzotriazole cyclohexylamine salt, etc. are also used. can do. A running copper wire is immersed in the rust preventive solution, and then the copper wire is passed through the heated vapor atmosphere of the rust preventive solution, or this process is repeated to form a rust preventive film with benzotriazole on the surface of the copper wire. For example, the container for forming the wire is formed by installing pulleys in multiple stages at the upper and lower parts of the container, and providing an inlet and an outlet for copper wire.
It is preferable that the copper wire be inserted through the inlet, and be drawn out from the outlet by making the copper wire go around the upper and lower pulleys in multiple stages. Then, add benzotriazole-water-1, so that about 1/3 of the lower pulley is immersed.
By pouring 1,1 trichloroethane-based anti-corrosion solution into the container and heating it to 50-70℃, the space inside the container will be
A vapor atmosphere is formed by the anti-rust solution. The upper end of the container is cooled to prevent the vapor components from volatilizing, and the container is repeatedly immersed and passed through the vapor atmosphere.
Forms a rust-preventing film on running copper wires. Next, the ratio of the length of the running copper wire immersed in the anti-rust solution to the length of the copper wire passing through the heated vapor atmosphere of the anti-rust solution is set to 1. In this case, it is preferable to set the latter to a range of 1 or more. It is preferable to lengthen the length of the tube through which it passes through the steam atmosphere inside the container, but it should not be made longer than necessary. The longer it is, the larger the container will be,
Circulating the copper wire becomes a hassle. The copper wire to be run is preferably a copper wire that has residual heat after continuous drawing or continuous softening, and it is preferable to use a copper wire whose surface has been pretreated, for example, by steam cleaning. is preferred. [Function] Even if a copper wire is immersed in a benzotriazole rust preventive solution heated to 50 to 70°C and dried, a rust preventive film with excellent corrosion resistance cannot be formed on the copper wire. In the present invention, pulleys are installed in multiple stages at the upper and lower parts of the container, an inlet and an outlet are provided for the copper wire, the copper wire is inserted from the inlet, and the copper wire is passed around the multiple pulleys at the upper and lower parts many times. so that the copper wire can be pulled out from the outlet part, and add benzotriazole to about 1/3 of the lower pulley, or so that the length of the copper wire that is immersed in the solution is equal to the length of the copper wire that is passed through the steam atmosphere. - A 1,1,1 trichloroethane-based rust preventive solution is poured into the solution, the rust preventive solution is heated to 50 to 70°C, a running copper wire is immersed in the rust preventive solution, and then,
When a copper wire is passed through a vapor atmosphere of a heated rust preventive solution, or when the copper wire is pulled out from the outlet while repeating this process, a rust preventive film with excellent corrosion resistance can be formed on the surface of the running copper wire. [Example] Examples and comparative examples of the present invention will be described below based on the drawings. 1 is a copper wire, 2 and 3 are pulleys, 4 is a steam cleaning pipe for pretreatment, 5 is an air wiper, 6 is a container for storing a multi-tiered upper pulley 7 and lower pulley 8;
9 is the inlet of the copper wire; 10 is the outlet of the copper wire; 11
12 is an auxiliary tank for antirust solution, 13 is a pump for liquid feeding, 14, 15, 16 are connecting pipes, 17
is a heater, 18, 19 are valves, 20, 21, 2
2 and 23 are spaces inside the container 6, 24 is a winding machine, and 2
5 is a cooling section, and A, B, C, and D are liquid levels in the container 6. Example 1 Next, the manufacturing method of the present invention will be explained based on FIG. First, dissolve 1.97 kg of benzotriazole in 5 ml of methyl alcohol, add 80 kg of water and 1,1,
1 and trichloroethane 15 to prepare a rust preventive solution with a benzotriazole concentration of 1.5% by weight, and transfer the solution to the auxiliary tank 12. The anti-corrosion solution is transferred to the container 6 by the liquid feeding pump 13.
The liquid is sent to about 1/3 of the liquid level A of the lower pulley 8 inside, and while flowing back from the overflow part 11 to the auxiliary tank 12,
The rust preventive solution is heated by the heater 17 so as to maintain the temperature of the solution at 70°C. Then, in order to remove the water-soluble lubricating oil adhering to the surface of the 2.0 mmφ hard copper wire 1 drawn at a drawing speed of about 710 m/min by a continuous wire drawing machine, the hard copper wire was passed through the pulleys 2 and 3. Adhering dirt and hot water are removed by an air wiper 5 through a steam cleaning pipe 4 provided in between. The pretreated hard copper wire 1 is passed through the inlet 9 to the container 6 [Container size: width 40 cm x length 25 cm x height 150 cm, pulley diameter:
20cm, distance between pulley axes: 120cm, number of pulleys: 3 on each of the upper and lower parts], make a number of turns between the upper and lower pulleys 7 and 8 in the container 6, and pull it out from the outlet 10. The antirust solution adhering to the surface of the copper wire 1 is removed by the air wiper 5 and dried, and then the winding machine 24
I wound up 80kg of 2.0mmφ hard copper wire 1. Example 2 80 kg of hard copper wire 1 with a diameter of 2.0 mm was wound up using the winder 24 in the same manner as in Example 1, except that the temperature of the anticorrosive solution was maintained at 55°C. Embodiment 3 Next, a description will be given based on FIG. 2. The liquid temperature of the anti-rust solution is set to 55°C, and the pump 13 for sending liquid from the auxiliary tank 12 is set so that the length of the copper wire immersed in the anti-rust solution is equal to the length of the copper wire passed through the steam atmosphere 21.
The liquid is fed to the liquid level B in the container 6 by
The same procedure as in Example 1 was carried out except that the flow was returned to the auxiliary tank 12 from 1', and 80 kg of hard copper wire 1 with a diameter of 2.0 mm was wound up with the winding machine 24. Comparative Example 1 Example 1 except that the temperature of the antirust solution was 25°C.
In the same manner as above, 50 kg of hard copper wire 1 with a diameter of 2.0 mm was wound up with the winding machine 24. Comparative Example 2 Example 1 except that the temperature of the antirust solution was 40°C.
In the same manner as above, the hard copper wire 1 of 2 mmφ is passed through the winding machine 2.
I wound up 50kg with 4. Comparative Example 3 The liquid temperature of the anti-corrosion solution was set to 65°C, the liquid level in the container 6 was brought up to the liquid level C at the lower end of the upper pulley 7 shown in FIG. Go, 2mmφ
The hard copper wire 1 was wound up by the winding machine 24. Comparative Example 4 Comparative Example 3 except that the temperature of the anti-rust solution was 25°C.
In the same manner as above, the hard copper wire 1 of 2 mmφ is passed through the winding machine 24.
I rolled it up. Comparative Example 5 The liquid temperature of the anti-rust solution was set to 65°C, the liquid level in the container 6 was pumped to the liquid level D shown in FIG. The copper wire 1 was wound up by a winding machine 24. Samples were taken from the various 2 mmφ hard copper wires obtained, immersed in an aqueous sodium sulfide solution with a concentration of 100 ppm for 30 seconds at room temperature, taken out, and subjected to a corrosion resistance test in which the state of discoloration on the surface of the hard copper wires was visually observed. The results are shown in Table 1. The criteria for determining corrosion resistance are: ◎ indicates original copper color, ○ indicates copper color with no discoloration, △ indicates discoloration in some places,
It was evaluated as lacking in practicality, and marked with an "X" as showing discoloration throughout. As can be seen from the results, Examples 1 to 3 all show good results with excellent corrosion resistance.
As can be seen from the figure, the anti-rust solution is fed to the liquid level C at the lower end of the upper pulley 7, and the solution is passed between the pulleys 7 and 8 at high speed (approximately
When the hard copper wire 1 is rotated many times at a speed of 710 m/min,
Even if the vapor space 22 exists in the container 6, the distance between the lower end of the pulley 7 and the liquid level C becomes very close.
The surface of the hard copper wire is always covered with the rust preventive solution pulled up by the running copper wire, and the state is the same as that of immersion, and the hard copper wire is not exposed to the vapor atmosphere of the rust preventive solution. Therefore, it is similar to the conventional rust prevention treatment method of simply dipping, and does not form a good rust prevention film. In Comparative Example 5, a good rust preventive film was not formed because the solution passed only through the vapor atmosphere of the rust preventive solution.

〔Effect of the invention〕

As explained above, according to the manufacturing method of the present invention, it is possible to form a rust-preventing film with excellent corrosion resistance on the surface of a copper wire. It is highly effective because it can sufficiently prevent the problem of discoloration of the copper wire surface and can be applied to stranded copper wires for outdoor insulated wires where corrosive rainwater can enter.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of manufacturing the corrosion-resistant copper wire according to the present invention, and Figs. 2 and 3 are explanatory diagrams of the liquid level position in which the container is filled with the anticorrosive solution. It is as follows. 1... Copper wire, 2, 3... Pulley, 4... Steam cleaning pipe for pretreatment, 5... Air wiper, 6... Container, 7... Upper pulley, 8... Lower pulley, 9... Copper wire inlet part, 10... Copper wire outlet part, 11... Liquid overflow part, 12... Auxiliary tank for antirust solution, 13... Liquid feeding pump, 17... Heater, 20, 21,
22, 23... Spaces within the container corresponding to liquid levels A, B, C, and D within the container 6.

Claims (1)

[Claims] 1. When running a copper wire through a three-component rust preventive solution of benzotriazole, water, and chlorine solvent heated to at least 50°C or higher in a container, the copper wire passes through the rust preventive solution and the vapor atmosphere of the solution. A method for manufacturing a corrosion-resistant copper wire, characterized in that a rust-preventing film with benzotriazole is formed on the surface of the running copper wire by repeating this process.