JPH0359769B2 - - Google Patents

Description

[Detailed description of the invention]

"Industrial Application Field" The present invention relates to a method for manufacturing deformed composite wires such as aluminum-coated deformed steel wires used in optical fiber composite power transmission lines, by drawing from a seed core material of a special shape. The present invention relates to a method for manufacturing a composite wire having a coating layer of uniform thickness. "Prior Art" Conventionally, as a method for manufacturing deformed aluminum-coated steel wires used for optical fiber composite power transmission lines and the like, a method is known in which a wire-drawing process is performed on an aluminum-coated base material. This manufacturing method is a method in which the outer surface of a steel wire is coated with an aluminum layer to form an aluminum coated base material, and then the wire is finished into a predetermined shape by performing diameter reduction processing using a die. ``Problems to be Solved by the Invention'' However, in the past, when a deformed aluminum-coated steel wire was manufactured by the method described above, when coating the steel wire with an aluminum layer, it was difficult to form the aluminum coating layer to a uniform thickness. Even in this case, a problem occurred in that the thickness of the aluminum coating layer became locally non-uniform during the diameter reduction process using a die. This is because when performing diameter reduction using a die, the steel wire is processed through the aluminum coating layer with low hardness, and the diameter is reduced from a round wire to a strip with an irregular cross section, so the compressive force that acts during diameter reduction is The core material (steel wire) tends to be processed into a shape different from the shape of the die hole, resulting in uneven thickness of the aluminum coating layer. Therefore, conventionally,
A deformed aluminum coated steel wire is manufactured using the method described below based on FIGS. 5 to 7. As shown in FIG. 5, when producing an aluminum-coated steel wire 3 having a substantially fan-shaped cross section by covering a steel wire 1 with an aluminum coating layer 2, this conventional method has a similar shape to that of the aluminum-coated steel wire 3. In this method, a seed wire 4 shown in FIG. 6 having a large cross-sectional area is prepared, and this seed wire 4 is subjected to a diameter reduction process to produce the required aluminum-coated steel wire. However, when an aluminum-coated steel wire with a substantially fan-shaped cross section is manufactured by the conventional method, the processing rate in the major axis direction is substantially larger than that in the minor axis direction, and the machining of the peripheral portion is difficult. The size of the ratio affects the wire drawability and greatly influences the thickness of the aluminum coating layer and the shape of the core material, resulting in the problem of uneven thickness of the aluminum coating layer 6 as shown in Fig. 7. It was happening. This indicates that by machining similar shapes, the pressure (contact pressure) applied by the die to the surface of the machined part becomes uneven, and as a result, the soft aluminum moves to the area where the contact pressure is low. It is something. The reason for the phenomenon in which soft aluminum moves to areas with lower surface pressure when wire drawing is performed with similar shapes is shown in Figures 8 and 9.
This is presumed to be due to the reasons explained below based on the example shown in the figure. In addition, in the examples shown in FIGS. 8 and 9, for ease of explanation, the case where only the core material is used without the covering layer is assumed. The cross section shown in Figure 8A is 20 mm long and 40 mm wide.
The seed line 15 is a cross section shown in Figure 8B, and the length is 10.
When drawing an aluminum-coated steel wire 16 with a similar shape of 20 mm wide and 20 mm wide using a die, the die and the seed wire 15
It seems that the contact state is as shown in FIG. 9A in the horizontal direction and as shown in FIG. 9B in the vertical direction. That is, in the wire drawing process using the die 21, in the horizontal dimension reduction shown in FIG. 9A, the horizontal dimension of the seed line 15 is reduced from 40 mm to 20 mm, and in the vertical dimension reduction shown in FIG. 9 B, the seed line is reduced. The vertical dimension of 15 is 20mm.
It will be reduced to 10mm. Therefore, as shown in FIGS. 9A and 9B, the position where the seed line 15 reaches the die hole of the die 21 is different in the vertical direction and the horizontal direction. As a result, machining proceeds from the part that is larger in size and reaches the die hole first.
It is thought that the softer aluminum will move to the part where the dimensions are smaller and machining will be delayed. From the above, it has become clear that the conventional idea that uniform processing is possible if the shapes are similar is incorrect. In addition, if such a difference in processing rate occurs, there is a risk of burn-in during diameter reduction processing, so conventionally,
An expensive lubricant containing molybdenum disulfide or the like is used, but even with this lubricant, seizure tends to occur. The part where this kind of seizure occurs is not the entire circumference of the workpiece, but
This phenomenon is particularly likely to occur in areas where processing is difficult and where the coating layer is thin, and this fact also shows the non-uniformity of processing in conventional methods. The present invention was made in view of the above problems, and
It is an object of the present invention to provide a method capable of manufacturing a deformed composite wire having a metal coating layer of uniform thickness. "Means for Solving the Problems" In order to solve the above-mentioned problems, the present invention provides a structure in which a metal core material having a cross-sectional shape surrounded by three or more sides is surrounded by a metal core material that is larger than the metal core material. In a method for manufacturing a deformed composite wire formed by forming a metal coating layer with low hardness, each of a plurality of sides constituting a cross section of a metal core material in the final shape to be obtained after processing is lengthened by the same length. Using a seed core material with a cross-sectional shape consisting of two sides, a metal coating layer of uniform thickness is formed on this seed core material, and then wire drawing is performed, so that all the individual sides of the metal core material have the same size. , to form an irregularly shaped composite line. "Operation" If the method of the present invention is carried out, each side will be reduced in diameter by the same dimension on three or more sides constituting the cross section of the seed core material, so each side will be reduced in diameter uniformly. Since the seed core material can be equally reduced over the entire circumference, it is possible to manufacture a deformed composite wire having a metal coating layer of uniform thickness, and it is also possible to prevent seizure during wire drawing. "Example" FIGS. 1 and 2 are for explaining an example of the method of the present invention. When manufacturing an aluminum-coated steel wire 10 having a substantially fan-shaped cross section as shown in FIG. First, as shown in FIG. 1, a base material 13 having a substantially fan-shaped cross section is prepared, in which a metal coating layer 12 made of Al is formed around a seed core material 11 having a substantially fan-shaped cross section. This base material 13 has a shape in which the diameter of the aluminum-coated steel wire 10 is increased uniformly over its entire length. That is, the length a of the vertical side along the cross section of the base material 13 is set to the length A of the vertical side of the aluminum-coated steel wire 10 in the final shape plus a predetermined length. The dimension b of the lateral side (arc in this example) along the cross section of 13 is the length obtained by adding the predetermined length to the lateral side dimension B of the aluminum-coated steel wire 10 in the final shape. is set to As a matter of course, the seed core material 11 having a fan-shaped cross section consists of four sides, and the left and right sides of the fan-shaped shape shown in FIGS. 1 and 2 both have the same dimensions and the value is a.
Therefore, the dimensions of the two left and right pieces of the seed core material 11 are the same. Of the upper and lower sides (arcs) of the seed core material 11, the upper side (arc) has the value of b explained earlier, but the lower side (arc)
Of course, the dimension is the sum of the lower side (arc) of the fan-shaped aluminum-coated steel wire 10 shown in FIG. 2 plus a predetermined length. Next, a die is used for the base material 13 to reduce the area reduction rate.
The aluminum-coated steel wire 10 is manufactured by performing diameter reduction processing at a constant thickness of 15 to 25%. Here, the range of the area reduction rate was limited as mentioned above because if the area reduction rate is greater than 25%, the pulling force required for wire drawing becomes large and wire breakage may occur.
This is because if the cross-sectional area reduction ratio is less than that, only the vicinity of the surface layer will be processed, defects will occur in the center of the core material, and the number of wire drawings will increase. When performing the diameter reduction process as described above, in the cross section of the base material 13, the diameter reduction ratio of the horizontal sides is different from the diameter reduction ratio of the vertical sides, but the diameter reduction dimension of the vertical sides is Since the reduced diameter dimensions of the horizontal sides are the same, the diameter can be reduced uniformly in both directions (i.e., all around the circumference), creating a coating layer with a uniform thickness as shown in Figure 2. The aluminum-coated steel wire 10 can be manufactured. In addition, since the wire is drawn by reducing the diameter equally on the vertical and horizontal sides, the processing rate in the peripheral area can be made uniform, and seizure during wire drawing can be prevented. Furthermore, since the pressure applied to the die can be made uniform on the vertical and horizontal sides, it is possible to prevent the die from wearing out unevenly, and the life of the die can be extended. Therefore, instead of an expensive lubricant containing molybdenum disulfide, a normal, inexpensive lubricant can be used, and manufacturing costs can be reduced. Here, in the case of wire drawing with equal thickness as described above, the relationship between the die and the base material is as described below based on the examples shown in FIGS. 3 and 4. Presumed. Note that the examples shown in FIGS. 3 and 4 will be explained with the aluminum coating layer omitted for ease of understanding. Here, the cross section shown in Figure 3A and the vertical 24
When drawing a base material 17 with a diameter of 34 mm and a width of 34 mm into an aluminum coated steel wire 18 with a cross section of 10 mm in length and 20 mm in width using a die, the state of contact between the die 21 and the base material 17 is as follows. It seems that the horizontal direction is as shown in FIG. 4A, and the vertical direction is as shown in FIG. 4B. That is, by the lateral reduction shown in FIG. 4A, the base material 1
Reduce the horizontal dimension of 7 from 34mm to 20mm, and make
In the vertical wire drawing state shown in , the vertical dimension of the base material 17 of 24 mm is reduced to 10 mm. Therefore, as shown in FIGS. 4A and 4B, the diameter is reduced by the same value (14 mm) in the vertical and horizontal directions, and in this case, the outer peripheral portion of the base material 17 reaches the die hole of the die 21. It can be estimated that the position is the same in the vertical and horizontal directions along the drawing direction. That is,
As a result of the base material reaching the die hole at the same time in both the large-sized portion and the small-sized portion, it can be assumed that the soft aluminum portion is wire-drawn without flowing in other directions. As a result, it can be assumed that uniform processing progresses. Note that the method described above applies to a deformed coated composite wire consisting of a coating layer made of a metal other than aluminum and a core material made of a metal material other than steel, and the core material is coated with a coating layer that is softer than the core material. Of course, the present invention can also be applied to other irregularly shaped composite lines to be formed. Manufacturing example 1 When manufacturing an aluminum-coated steel wire with a cross-sectional area of 9.6 mm ² and a final cross-sectional shape of approximately fan-shaped, the cross-sectional area of 41 mm ² obtained by increasing the diameter of this approximately fan-shaped cross-sectional shape to the same thickness is obtained. Base material (0.71%C-0.75%Mn-0.2%Si-
The remainder Fe) was prepared. After coating this base material with aluminum at a coverage rate of 30%, wire drawing was performed at a rate of area reduction of 15 to 23% to produce an aluminum coated steel wire. This aluminum-coated steel wire had an aluminum coating layer with a uniform thickness, and no seizure occurred during wire drawing. The results of measuring the thickness of the aluminum coating layer of the aluminum coated steel wire produced in this manner are shown in Table 1 below. "Comparative Example" In order to manufacture an aluminum-coated steel wire whose final cross-sectional shape is approximately fan-shaped, a deformed steel wire with a cross-sectional shape similar to this aluminum-coated steel wire and a cross-sectional area of 40.5 mm ² was prepared. Then, this was subjected to a panting treatment, and then coated with an aluminum layer to a coverage rate of 30%, and then subjected to a wire drawing process. During this wire drawing process, seizure occurred at the ends of the deformed steel wire in the major diameter direction. The results of measuring the thickness of the aluminum coating layer of the aluminum coated steel wire produced as described above are shown in Table 1 together with the results of the previous production examples.

[Table] From the results shown in Table 1, the aluminum coating layer of the aluminum-coated deformed steel wire of the manufacturing example manufactured by applying the method of the present invention is superior to that of the aluminum-coated deformed steel wire manufactured by the conventional method. It is clear that the thickness is more uniform than that of the aluminum coating layer, and it is clear that the present invention can produce a deformed steel wire having a coating layer of uniform thickness. In the present invention, as shown in Table 1,
The deviation of the thickness of the Al layer from the average thickness is
While the difference was about 3%, the difference was as much as ±20% in the comparative example, and it became clear that uniform processing could be achieved by the method of the present invention. "Effects of the Invention" As explained above, the present invention forms a coating layer on a seed core material whose diameter is uniformly increased by the same dimension in all pieces of the cross-sectional shape of the core material in the final shape to be obtained. The diameter is reduced by the same size on the vertical and horizontal sides, and the diameter can be reduced while maintaining the thickness of the coating layer, making it possible to create a coating layer with a uniform thickness. There is an effect that it is possible to manufacture a deformed composite wire having the following properties. Furthermore, since the diameter of the seed core material is uniformly reduced on the vertical and horizontal sides, the die does not seize during wire drawing, and the life of the die is extended.

[Brief explanation of drawings]

Figures 1 and 2 are for explaining one embodiment of the present invention. Figure 1 is a cross-sectional view of a seed core material, and Figure 2 is an aluminum coating manufactured by the method of the present invention. A cross-sectional view of a steel wire, FIGS. 3A and 3B are front views showing examples of seed lines for estimating the wire drawing state in the present invention, and FIGS. 4A and B are cross-sectional views of steel wires shown in FIG. An explanatory diagram showing an estimated example of the wire processing state, Fig. 5 is a cross-sectional view showing an irregular cross-section strip to be manufactured by the conventional method, and Fig. 6 is a cross-sectional view of the seed line used in the conventional method. 7 is a cross-sectional view of an aluminum coated irregular cross-section strip manufactured by the conventional method, FIG. 8 A and B are front views showing the base material for estimating the conventional wire drawing state, and FIG. Figures A and B are explanatory diagrams showing a state in which the base material shown in Figure 8 is being wire-drawn. 10... Aluminum coated steel wire (deformed composite wire), 11
... Seed core material, 12 ... Aluminum coating layer, 13 ... Base material, 21 ... Dice.

Claims (1)

[Claims] 1. Manufacture of a deformed composite wire by forming a metal coating layer having a lower hardness than the metal core material around a metal core material having a cross-sectional shape surrounded by three or more sides. In the method, each of the plurality of sides constituting the cross section of the metal core material in the final shape to be obtained after processing is lengthened by the same length, using a seed core material having a cross-sectional shape made up of sides, An irregular shape characterized by forming a metal coating layer of uniform thickness on this type of core material and then subjecting it to wire drawing processing, reducing all the individual sides of the metal core material by the same dimension to form an irregularly shaped composite wire. Method of manufacturing composite wire.