JPS6047685B2 - Manufacturing method of steel core aluminum stranded wire - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method for manufacturing a steel-core aluminum stranded wire that forms a hydrophilic layer on the outer surface to prevent the occurrence of corona caused by rainwater etc. adhering to the surface in a spherical shape. .

This type of steel-core aluminum stranded wire is manufactured by chemically surface-treating the outer surface of the aluminum stranded wire layer with alkaline liquid, acidic liquid, etc.
It is known that the surface is roughened to form a hydrophilic layer.

Normally, during this surface treatment, it is necessary to heat the surface of the steel-core aluminum stranded wire to a predetermined temperature, for example, about 50 to 1500C.

Conventionally, a method using a radiant furnace, a burner, etc. has been adopted as a means for this heating.

However, such methods have poor heating efficiency;
When incorporated into the manufacturing process of steel core aluminum stranded wire, the manufacturing speed has to be significantly reduced.

In addition, the heating method described above takes a long time to reach a certain temperature (poor start-up performance), and cannot follow the start-up and stoppage of steel-core aluminum stranded wire manufacturing equipment, such as a wire stranding machine.
The present invention improves these drawbacks by forming two or more aluminum stranded wire layers on a steel core, heating the aluminum stranded wire layer using high frequency heating, and then chemically roughening the aluminum wire layer. This method is characterized in that a hydrophilic layer is formed on the outer surface of the aluminum stranded wire layer by chemical treatment.

The reason why the aluminum stranded wire layer is limited to two or more layers is that when there is only one aluminum stranded wire layer, gaps are created between the aluminum wires, and magnetic flux during high-frequency heating leaks from this gap. However, the high-frequency energy can efficiently heat the aluminum stranded wire layer, heating up the internal steel core, and therefore the steel core will heat up before the aluminum stranding layer reaches the specified temperature (50 to 150°C). This is because the steel core is heated abnormally and reaches a dull temperature, reducing the strength of the steel core.

Next, the present invention will be explained in detail based on illustrated embodiments.

Fig. 1 shows an example of application in which the present invention is incorporated into a continuous production process for steel-core aluminum stranded wire, including a wire stranding process. The capstan 4 indicates a winding machine, and the manufacturing process is similar to the manufacturing process of known steel core aluminum stranded wire.

The present invention incorporates a high-frequency heating device 5 and a chemical surface roughening treatment tank 6 in this order in the post-process of the wire twisting machine 2, and the wire twisting machine 2 forms two layers of aluminum twisted wire on the steel core. A layer or more is formed and heated to a predetermined temperature (50 to 150°C) using a high frequency heating device 5.
The outer surface of the aluminum stranded wire layer is then roughened in a treatment bath 6 to form a hydrophilic layer.

The high-frequency heating device 5 includes an induction heating coil 7, a matching capacitor 8, and a high-frequency oscillator 9, and a steel-core aluminum stranded wire 1 is passed through the approximate center of the heating coil 7 to heat it. At the same time, the heating temperature can be controlled by controlling the output of the oscillator 9.

Furthermore, this high frequency oscillator 9 is connected to a speed detector 10, for example, a pulse generator, provided on the take-up capstan 3, and is configured to control the output in proportion to the take-up speed of the take-up capstan 3, so that when the take-up speed changes, However, the heating temperature is kept at a predetermined value. The chemical surface roughening treatment tank 6 has a structure in which the steel-core aluminum strands 1 pass through the treatment liquid, and a structure in which the treatment liquid is sprayed in a mist onto the outer surface of the steel-core aluminum strands 1 passing through. You can arbitrarily adopt such things.

The processing liquid is an alkaline liquid or an acidic liquid, for example, a concentration of 1.5.
~5% caustic soda solution may be used. Furthermore, the first
In the application example shown in the figure, an example is shown in which the high-frequency heating device 5 and the chemical surface roughening treatment tank 6 are incorporated in the pre-process of the take-off capstan 3;
Incorporate it into the post-process! Alternatively, the output control of the high frequency heating device 5 may be made proportional to the winding speed of the winder 4,
In some cases, independent control may be performed without interlocking with others.

Further, washing with water, drying treatment steps, etc. may be arranged after the surface treatment. Next, an example will be described in which a steel core aluminum stranded wire is manufactured in the manufacturing process of the configuration shown in FIG. Example 1 Three layers of 4 aluminum strands (wire diameter 4.8W$Lφ) were formed on a copper core consisting of 7 strands of 3.2TI$lφ, and this was formed into a 3KHz1100KW1 coil with an inner diameter of 55Tn! 11
The aluminum stranded wire layer was heated to 100℃ using a high-frequency oscillator of φ, and then subjected to chemical surface roughening treatment using a 5% caustic soda solution to form a hydrophilic layer on the outer surface. The twisted wire is 20Tr1. /min.

When we measured the temperature rise between the steel core and the aluminum stranded wire layer during this heating, we found that the aluminum stranded wire layer reached a predetermined 10
Even when the temperature reached 0°C, the temperature of the steel core was only about 200°C, and the strength of the steel core was not reduced, and the condition of the hydrophilic layer was good, reliably preventing corona generation and obtaining a beneficial effect. Example 2 A steel-core aluminum stranded wire was manufactured under the same conditions except that the aluminum stranded wire layer in Example 1 was changed to two layers, and the temperature rise during heating was measured. The result was as shown in Figure 2.

Comparative Example 1 A copper-core aluminum stranded wire was manufactured using only one aluminum stranded wire layer in Examples 1 and 2, and the other conditions were the same, and the temperature rise during heating was measured, as shown in Figure 3. Before the aluminum stranded wire layer reached the predetermined temperature of 100° C., the steel core reached an abnormally high temperature of about 500° C., reaching the dulling temperature and reducing its strength.

According to the method of the present invention, high-frequency heating is adopted as a means of heating the steel-core aluminum stranded wire, so the heating temperature can be easily controlled by controlling the output, and the rising performance is also improved compared to the conventional method. Since the heating process is incorporated into the stranded wire manufacturing process, the manufacturing speed can be significantly increased compared to the conventional method. Moreover, since there are two or more aluminum stranded wire layers, even when the aluminum stranded wire layer is brought to the required temperature of 50 to 150° C., the steel core will not be abnormally overheated and the desired purpose can be achieved.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram illustrating the manufacturing process of steel core aluminum stranded wire to which the present invention is applied, Fig. 2 is an explanatory diagram illustrating an embodiment of the present invention, and Fig. 3 is an explanatory diagram illustrating a comparative example. It is. 1... Steel core aluminum stranded wire, 2... Wire stranding machine, 3... Take-up capstan, 4... Winding machine,
5... High frequency heating device, 6... Chemical surface roughening treatment tank.

Claims (1)

[Claims] 1 Form two or more aluminum stranded wire layers on a steel core, heat the aluminum stranded wire layer using high frequency heating, and then chemically roughen the aluminum wire layer to make the outer surface of the aluminum stranded wire layer hydrophilic. A method for manufacturing a steel-core aluminum stranded wire, characterized by forming layers.