JPS5919401B2 - Manufacturing method of copper oxide film wire insulated conductor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION For example, it has been proposed to form a thin copper oxide film on the surface of copper strands for strand insulation of power cable conductors.

Furthermore, as a method of forming an oxide film, it has been proposed to heat a copper wire and then immerse it in an oxidation treatment solution. However, when a copper wire is placed in an oxidizing solution, the temperature drops suddenly. This slows down the oxidation reaction rate. It is not possible to increase the linear speed. Purpose and Overview To prevent the temperature of the copper wire from dropping too much during the oxidation reaction.

It also speeds up the reaction rate, making it possible to increase the linear velocity. Therefore, in this invention, the oxidation treatment liquid is sprayed onto the heated copper wire.

First, an outline of the apparatus will be described (FIG. 1). This is an example in which wire drawing and annealing are used in tandem.

10 is a wire drawing machine, 12 is a copper wire, 14 is a take-up capstan, and 16 is a winding drum.

18 is a preheating chamber, and a gas seal 20 is provided at the inlet.

22 is a heating chamber.

A seal 24 is provided between the preheating chamber 18 and the preheating chamber 18 . However, this is not a perfect seal and allows gas to escape. 26 is a high frequency induction heating device, and 28 is a heating coil.

Note that other known heating devices (for example, electrical heating devices, etc.) can also be used. 30 is an oxidation treatment chamber.

A gap 34 is provided between the partition wall 32 and the heating chamber 22 to allow gas to pass therethrough. 36 is a shower tube, which is provided surrounding the copper wire 12.

Reference numeral 38 denotes an oxidation treatment liquid stored in a part of the bottom of the oxidation treatment chamber 30, which is, for example, a mixed aqueous solution of 5q1) sodium zincate and 5% sodium hydroxide.

40 is a heater for the oxidation treatment liquid 38;

The oxidation treatment liquid 38 is pumped into the shower cylinder 36 by the circulation pump 42.
from which it is ejected in the form of a shower or spray. 44 is a cooling chamber.

A seal 45 is provided between the chamber 30 and the oxidation treatment chamber 30 to substantially cut off gas. A cooling water tank 46 is provided in the lower part of the cooling chamber 44. The cooling water 48 is pumped to the pump 50. Circulate through cooler 52. A gas seal 54 is provided at the outlet of the copper wire 12. 56 is a blower for circulating inert gas.

Nitrogen gas is used as an example of an inert gas. gas heater 5
High-temperature nitrogen gas 60 heated to about 100 to 500° C., for example, is fed into the heating chamber 22 through the heating chamber 22 . A portion of hot nitrogen gas 60 enters preheat chamber 18 through seal 24 . Another part enters the oxidation treatment chamber 30 through the gap 34. Preheating chamber 18 and heating chamber 2 are heated by high temperature nitrogen gas 60.
2. The inside of the oxidation treatment chamber 30 is maintained at a high temperature. Furthermore, low-temperature nitrogen gas 62 that does not pass through the gas heater 58 is sent into the cooling chamber 44 . 6 and 4 are pipes for circulating nitrogen gas, 66 is a condenser, 68 is a moisture separator, and 70 is a nitrogen cylinder for replenishment.

Next, we will discuss the effect.

(1) Copper wire 12 is heated in the preheating chamber 18 to
Preheat it to about 0°C and place it in the heating chamber 22.

Therefore, the high frequency induction heating device 26
Heat to ℃. Since the heating chamber 22 is filled with high-temperature nitrogen gas 60, the temperature of the copper wire 12 hardly decreases.
Moreover, the surface enters the oxidation treatment chamber 30 without being oxidized. (
2) In the oxidation treatment chamber 30, the oxidation treatment liquid 38 is sprayed from the shower cylinder 36 to form a film of cupric oxide on the surface of the copper wire 12.

This acts as wire insulation. Note that since the oxidation treatment chamber 30 is filled with high-temperature nitrogen gas 60 and the oxidation treatment liquid 38 is sprayed, the temperature of the copper wire 12 does not drop suddenly. Since oxidation is carried out at high temperatures for a considerable period of time, the reaction rate becomes faster. (3) Then, the copper wire 121 is put into the cooling chamber 44 and cooled with nitrogen gas 62 (low temperature).

Note that air may be used for cooling instead of nitrogen gas. The temperature is further lowered to room temperature using cooling water 48. It is then washed, dried and wound onto a winding drum 16. Another Embodiment In a heating oxidation treatment chamber 72 in which a heating chamber 22 and an oxidation treatment chamber 30 are connected together, heating is performed by, for example, a high frequency induction heating device 26, and at the same time, an oxidation treatment liquid 38 is sprayed from a shower cylinder 36. , perform oxidation treatment.

Note that in this case, an electrical heating device cannot be used as a heating means for the copper wire 12. This is because the formation of an insulating oxide film makes it difficult to conduct electricity. A high frequency induction heating device 26 may be used. Note that the present invention can also be carried out separately from annealing.

In that case, the heating temperature is set to about 100 to 300°C. This can be done not only for solid wires but also for stranded wires.

"Figure 3" shows the change in temperature of the copper wire 12 over time.

A is the case of this invention, and B is the case of immersion in the oxidation treatment liquid 38. In the case of this invention, it is clearly seen that the oxidation reaction is carried out while maintaining a high temperature. Effects of the invention (1) Since the oxidation treatment liquid 38 is sprayed, the copper S is reduced compared to the case of dipping. 12 temperature does not drop suddenly.

Furthermore, the oxidation treatment liquid 3 was heated in a high-temperature inert gas.
8, the temperature of the copper internal wire 12 decreases even more. As a result, the reaction speed becomes very high, and the wire speed of the copper internal wire 12 can be increased, resulting in cost reduction. (2) As mentioned above, when the oxide film is formed, the wire 12 is still at a fairly high temperature;
Since it is pre-cooled with low-temperature gas and then passed through the cooling water 48, there is no fear that the oxide film will peel off due to heat shock caused by rapid cooling.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an apparatus used to carry out the present invention, FIG. 2 is an explanatory diagram of the main parts of an apparatus used in another embodiment, and FIG. 3 is a diagram of the change in temperature of the copper wire 12 over time. 18... Preheating chamber, 22... Heating chamber, 26... High frequency induction heating device, 30... Oxidation treatment chamber, 36... Shower 18... Oxidation treatment liquid.

Claims (1)

[Claims] 1. A process of heating the continuously running copper internal wire 12 in a high-temperature inert gas, and spraying a high-temperature oxidation treatment liquid 38 onto the heated copper internal wire 12 in the high-temperature inert gas. , is characterized by forming a film of cupric oxide on the surface of the copper internal wire 12, and precooling the copper internal wire 12 with the oxide film formed thereon with low-temperature gas, and then passing it through cooling water 48. A method for producing a copper oxide film stranded insulated conductor.