JPH06134516A - Manufacture of long size, highly accurate ultra fine steel wire - Google Patents

Abstract

PURPOSE:To dissolve the dispersion of a wire diameter due to the uneven wear of a die and manufacture a long size, highly accurate ultra fine steel wire by continuously drawing the wire while continuously or intermittently revolving the die in the final stage. CONSTITUTION:A base stock 1 for a steel wire is drawn and reduced its diameter with area reducing dies 5a-5n which are in multiple stages, arranged between capstans 4a, 4b and 4c, 4d. A rotary die 7 is provided to finish the projecting parts of die mark which are inevitably generated and developed due to these area reducing dies. A sintered diamond or artificial single crystal diamond which is hard to generate uneven wear is used for the rotary die 7 which is given about one revolution per a wire-drawing length of, for example, 100-500m or at a timing so that cracking is not generated, for example, one revolution at several seconds' interval. Consequently, the projecting parts on the surface of steel wire is slightly rolled down and drawn, so die wear is uniformized and variation in the outside diameter of the drawn wire is not imparted. It is preferable to take the reduction of area as <=1%. Next the final correction is executed with a skin pass die 8 whose reduction of area is zero.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention requires ultra-long and highly accurate dimensions for use in, for example, gauze for screen printing, reinforcing material for timing belts in the field of rubber products, or oil filters in the field of filtration products. The present invention relates to a method for producing a high-strength ultrafine steel wire.

[0002]

2. Description of the Related Art Conventionally, the high-strength ultra-fine steel wire used in the above-mentioned industrial fields is obtained by subjecting a steel wire material obtained by hot rolling of approximately 5 mmφ to surface treatment (pickling, lubrication, etc.). Is a thin wire having an outer diameter of approximately 10 to 30 μmφ, which is manufactured by repeatedly performing heat drawing as an intermediate step by a multi-stage die wire drawing method (slip type wire drawing machine).

The outer diameter accuracy of the high-strength ultrafine steel wire product obtained by such a manufacturing method is determined by the die shape in the final stage of the manufacturing process. Generally, this die is made of diamond with little wear, but the die wears in accordance with the wire drawing length of the steel wire, and especially in the diamond die, the wear progresses along the crystal direction, causing uneven wear,
This causes the accuracy of the outer diameter to deteriorate, and is about 50 km.
With the wire drawing, the outer diameter deviation has reached 0.4 μm.

On the other hand, as in the above-mentioned screen-printed gauze, for example, the screen characteristics generally require that the width of the printed line be 100 μm or less and the line width variation of the printed line be ± 10 μm or less. In electronics related to wiring, thick film ICs, resistors, etc., higher densification is promoted, and in printing wiring etc., a high-precision screen suitable for ultrafine line printing with a line width of 50 μm can be stably obtained. Is requested.

In the industrial field where high density and high accuracy and high stability are required such as products such as such screens, the accuracy of the outer diameter of the ultrafine steel wire which is the basic constituent part of the product is It is extremely important and adds value to the product (eg I
High density of C board wiring, etc.) will be greatly affected. Therefore, in order to improve the above-mentioned outer diameter accuracy and meet the requirements of the product, in order to reduce wear of the die and the steel wire, lubrication improvement technology such as surface treatment is used for wire drawing,
At present, there is a limit, and it is not in a situation where the outer diameter deviation of 0.2 μm or less at the wire length of 50 km or more, which is a product requirement for ultrafine steel wire, is sufficiently satisfied.

[0006]

SUMMARY OF THE INVENTION The present invention is to solve the problems at present in the multi-stage die wire drawing method as described above. By suppressing die wear and prolonging the life, It is an object of the present invention to provide a method for producing a long, high-precision, ultrafine steel wire which can eliminate the variation in wire diameter due to uneven wear.

[0007]

In order to achieve the above object, the present invention has the following structures. (1) Finishing For steel wire material of intermediate size to be used for ultrafine wire drawing,
After the heat treatment, in the process of manufacturing ultra-fine steel wire by the multi-stage die wire drawing method, the final surface-reducing die is used to determine the approximate final wire diameter, and a rotating mechanism is added to the final-stage die that has been continuously installed. 1. A method for producing a long, high-precision ultra-fine steel wire, which comprises continuously drawing wire while rotating the wire continuously or intermittently. (2) Finishing For steel wire material of intermediate size for ultra-fine wire drawing,
In the process of manufacturing ultra-fine steel wire by the multi-stage die wire drawing method after heat treatment, determine the final wire diameter with the final surface-reducing die, and reduce the surface area by the same as the inner diameter of the final surface-reducing die or 1% or less. A method for manufacturing a long, high-precision ultra-fine steel wire, which comprises finally passing a skin pass die having a die diameter of (3) Finishing For steel wire material of intermediate size to be used for ultrafine wire drawing,
After the intermediate heat treatment, in the process of manufacturing ultra-fine steel wire by the multi-stage die wire drawing method, a die with a rotating mechanism is added to the final surface-reducing die that determines the final wire diameter, and the die is drawn during wire drawing. Is continuously or intermittently rotated for continuous wire drawing, and is the same as the inner diameter of the rotary die or 1%.
A method for producing a long, high-precision ultra-fine steel wire, which comprises finally passing a skin-pass die having a die diameter having the following surface reduction rate.

The present invention will be described in detail below. In order to produce a long ultra-fine wire, after removing the surface scale from a steel wire rod of a few mmφ that is usually formed by hot rolling as described above, a secondary wire drawing is performed to obtain a fine wire raw material of 100 to 300 μmφ. Wires are drawn by the multi-stage die drawing method. That is, for example, by using a plurality of surface-reducing dies 5a to 5n arranged in a wire drawing line as schematically shown in FIG. 4, as shown by dotted lines in the schematic diagram of FIG. Wires are drawn so that the surface ratios are almost the same. The inner diameter of the surface-reducing die 5 is composed of a diamond die 11 to enable high load wire drawing.

Prior to this multi-stage die wire drawing, the thin wire material is immersed in a lead bath or heat treated (patented) in an inert atmosphere to obtain a homogeneous structure, and if necessary, Ni
After surface treatment with, etc., it is passed through the die while supplying lubricating oil.However, drawing ultra-fine wire imposes a large load on the surface-reducing die, and in the conventional method, the latter-stage surface-reducing die has a particularly large load. Die wear increases with relatively small production volume. Therefore, if an attempt is made to obtain a long ultrafine wire, the dimensional accuracy of the final product will be deteriorated. According to the experience of the present inventor, in order to obtain a final product with a wire diameter of 20 μm, uneven wear of the final surface-reducing die progresses rapidly in the conventional method, and the final surface reduction die has
It was found that the outer diameter deviation reached 0.4 μm when the wire was drawn (see the dotted line in FIG. 3), which greatly exceeded the current target value of 50 μm or more and the outer diameter deviation of 0.2 μm or less.

The cause lies in the diamond forming the surface-reducing die. That is, especially for natural diamond, if a high load (friction) is continuously applied to this,
This is because, as shown in FIG. 6, wear or cracks 12 are generated along the cleavage plane in the crystal direction and grow to form an uneven wear die surface. Such uneven wear determines the die surface, especially the final shape that determines the product shape. The generation on the step-reducing die surface promotes the deterioration of the product dimensional accuracy. Therefore, it is necessary to replace the die at an early stage so that uneven wear does not occur.

The present invention uses a rotary die as the final die. By continuously or intermittently rotating the rotary die provided after the final surface-reducing die from the beginning of using a new die, the die-mark convex portion of the surface-reduced wire rod that is inevitably generated and grows in the preceding surface-reducing die. Is reduced each time it is rotated, and the wear of the die surface of the rotary die itself is made uniform to suppress uneven wear. At this time, it is preferable to use, for the rotary die, sintered diamond or artificial single crystal diamond that has no crystal direction or is dispersed (irregular) and is less likely to cause uneven wear. As shown by the solid line in Figure 1, it is desirable to reduce the surface reduction rate of the die by lowering the surface reduction rate on the final stage side with a high reduction area on the front stage and a reduction area on the rear stage. Wear can be further suppressed.

Further, in the present invention, it is effective to arrange the skin pass dies in tandem in the final stage subsequent to the rotary die. The skin pass die is to reduce the surface area of a thin wire that has been subjected to surface reduction by adjusting the diameter, and by combining it with a rotating die, the minute wire diameter variation that occurs in the rotating die can be improved, A product with dimensional accuracy can be obtained. On the other hand, depending on the product wire diameter, it may be carried out on the wire material immediately after the usual final surface-reducing die (non-rotating) treatment,
The dimensional accuracy is likewise improved.

FIG. 1 schematically shows an example of a line for carrying out the present invention. In the figure, 1 is a steel wire material to be treated. This steel wire material has a weight percentage of C: 0.7 to 0.9.
%, Si: 0.1 to 0.3%, Mn: 0.4 to 0.6
%, N ≦ 0.0004%, O ≦ 0.0004%, balance unavoidable impurities and Fe, and tensile strength 300 kg /
It is preferable that product characteristics of mm ² or more and elongation of 3% or less can be obtained. In addition, the surface may have Ni as needed.
Surface treatment such as plating facilitates wire drawing and imparts rust prevention and surface gloss. 2 is a payoff reel,
Send the coiled steel wire material to the wire drawing machine. 3 is a guide roll, and 4a to 4d are capstans. The capstan is a take-up drum having an outer surface whose diameter continuously changes from one end to the other end, and the steel wire raw material 1 is wound around the capstans 4a-4b and 4c-4d to exert a pulling force. It is fed while being wound in multiple stages from the small diameter portion toward the large diameter portion. 5a to 5n are surface-reducing dies. That is, a die tool for reducing the diameter of a steel wire material by adding a certain area reduction ratio between the capstans 4a-4b and 4c-4d.
It is arranged in multiple stages at the steel wire material passing position between them. Each of the surface-reducing dies 5a to 5n is provided with a lubricating oil supply nozzle 6 at the front thereof, or is immersed in the lubricating oil, and the steel wire material 1 is subjected to a predetermined surface-reducing rate in the state where the lubricating oil is applied. To extend and contract the diameter. Area reduction depends on the material diameter and the product diameter to be obtained,
Since the linear velocity increases and the load of the die increases in the latter stage, as shown by the solid line in FIG. 2, the initial area reduction rate is increased, and the lower the area reduction rate in the latter stage. Is good.

Reference numeral 7 denotes a rotary die, which is the essential point of the present invention. A steel wire having a die mark convex portion which is inevitably generated and grows by the surface-reducing die in the preceding stage is provided with the die mark convex portion while rotating. A die tool for reducing the outer diameter of a rolled steel wire, which is installed after the final surface-reducing die 5n. That is, since the convex portion on the surface of the steel wire is drawn under light rolling while rotating the die, the wear of the die is made uniform and the outer diameter of the drawn wire does not vary. The surface reduction rate of the rotary die is not particularly limited, but it is preferably 1% or less. The rotation of the die is linked with the wire drawing speed and the die rotating mechanism, and is continuously rotated in synchronization with the wire drawing speed so as to obtain a peripheral speed for a preset wire drawing length.
About the time, or the timing when a crack does not occur,
For example, it is intermittently performed once every few seconds.

Reference numeral 8 is also a skin pass die which is one of the main points of the present invention, and corrects the variation of the wire diameter of the steel wire drawn by the final surface-reducing die to improve the outer diameter accuracy. In addition, since minute wire diameter variations and line habits are generated even in the rotary die, the skin pass die 8 is arranged in tandem after the rotary die 7 and these are corrected to obtain a product having excellent outer shape accuracy. As described above, since the skin pass die is for correcting the variation in wire diameter and the line habit to adjust the diameter, it is not necessary to give the surface reduction rate substantially, and 1% or less is sufficient. 9 is a finishing capstan, 9'is a separate roller, and 10 is a product winding bobbin.

By carrying out the present invention with the above line configuration, an ultrafine wire having an excellent outer diameter accuracy of 20 μm or less (deviation of 0.2 μm or less) can be used for 150 km without exchanging dice. It can be manufactured over the above length.

[0017]

EXAMPLES As weight%, C: 0.82%, Si: 0.
24%, Mn: 0.52%, P: 0.009%, S:
0.007%, N: 0.0003%, O: 0.0003
%, The balance being a steel wire material consisting essentially of Fe was passed through the manufacturing line shown in FIG. 1 to manufacture a product having a wire diameter of 20 μm.

The conditions for wire drawing were set as follows. Steel wire material: Wire diameter 44μm, Ni plating on the surface Number of die reduction areas: 17 steps (pieces), first (first step) area reduction rate is 13%, and thereafter the area reduction rate is gradually reduced The reduction rate of the die is set to 5%. Rotating die: Continuous rotation 1 rotation / 200m, Area reduction rate 0% Skin pass die: Area reduction rate 1% The outer diameter deviation of the products continuously drawn for 150km under the above conditions was measured and found to be within 0.10μm for all products. there were. Similarly, the outer diameter deviation is 0.14 μm or less when the rotary die is finally placed after the final surface-reducing die, and the outer diameter deviation is 0.20 μm or less when the skin pass die is finally placed after the final surface-reducing die. Met. For comparison, the product manufactured by the conventional method that does not pass through the rotary die and the skin pass die has an outer diameter deviation of 0.2 μm at a continuous wire drawing length of 15 km and 0.4 μm at a continuous wire drawing length of 30 km. It has become extremely large. The wire drawing conditions of both products are shown in FIG. 3, but the product of the present invention can be an ultra-long product with ultra-high accuracy that is more than 10 times that of the conventional method.

[0019]

INDUSTRIAL APPLICABILITY As described above, the present invention continuously produces ultra-fine steel wire satisfying the requirements of ultra-high precision and ultra-long length required for screen printing gauze and the like with high productivity. Can be manufactured.

[Brief description of drawings]

FIG. 1 is an explanatory view schematically showing a production line of the present invention.

FIG. 2 is a diagram showing a situation of a surface-reducing die and a surface-reduction rate in a wire drawing line.

FIG. 3 is a diagram showing a relationship between a product wire drawing length and an outer diameter accuracy.

FIG. 4 is an explanatory view schematically showing a conventional manufacturing line.

FIG. 5 is an explanatory view showing a surface-reducing die.

FIG. 6 is an explanatory view showing a diamond die.

[Explanation of symbols]

 1: Steel wire material 2: Payoff reel 3: Guide roll 4a, 4b, 4c, 4d: Capstan 5a, 5n: Face-reducing die 6: Lubricating oil supply nozzle 7: Rotating die 8: Skin pass die 9: Finishing capstan 9 ': Separate roller 10: Winding bobbin 11: Diamond dies 12: Uneven wear

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[Procedure amendment]

[Submission date] September 3, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

FIG. 1 schematically shows an example of a line for carrying out the present invention. In the figure, 1 is a steel wire material to be treated. This steel wire material has a weight percentage of C: 0.7 to 0.9.
%, Si: 0.1 to 0.3%, Mn: 0.4 to 0.6
%, N ≦ 0.0004%, O ≦ 0.0004%, balance unavoidable impurities and Fe, and tensile strength 300 kg /
It is preferable that product characteristics of mm ² or more and elongation of 4% or less can be obtained. In addition, the surface may have Ni as needed.
If the surface is treated by plating or the like , wire drawing is easy and rust prevention and surface gloss can be imparted. 2 is a payoff reel,
Send the coiled steel wire material to the wire drawing machine. 3 is a guide roll, and 4a to 4d are capstans. The capstan is a take-up drum having an outer surface whose diameter continuously changes from one end to the other end, and the steel wire raw material 1 is wound around the capstans 4a-4b and 4c-4d to exert a pulling force. It is fed while being wound in multiple stages from the small diameter portion toward the large diameter portion. 5a to 5n are surface-reducing dies. That is, a die tool for reducing the diameter of a steel wire material by adding a certain area reduction ratio between the capstans 4a-4b and 4c-4d.
It is arranged in multiple stages at the steel wire material passing position between them. Each of the surface-reducing dies 5a to 5n is provided with a lubricating oil supply nozzle 6 at the front portion thereof or is immersed in the lubricating oil so that the lubricating oil is applied.
In the state, the steel wire material 1 is expanded and contracted at a predetermined reduction ratio. The area reduction rate is determined by the diameter of the material and the product diameter to be obtained, but the linear speed increases and the die load increases in the latter part, so as shown by the solid line in Fig. 2, the initial area reduction rate It is preferable that the value be increased so that the surface area is reduced in the subsequent stage.

Claims (3)

[Claims] 1. In a process of manufacturing an ultra-fine steel wire by a multi-stage die drawing method after heat-treating an intermediate-sized steel wire material to be used for finishing ultra-fine wire drawing, a final surface-reducing die is used to form a substantially final wire diameter. The manufacturing of a long, high-precision ultra-fine steel wire characterized by adding a rotating mechanism to the last-stage die provided continuously and continuously drawing the die while continuously or intermittently rotating the die. Method. 2. In the step of producing an ultra-fine steel wire by a multi-stage die wire drawing method after heat-treating an intermediate-sized steel wire material to be used for finishing ultra-fine wire drawing, a final surface-reducing die is used to form a substantially final wire diameter. The same as the inner diameter of the final surface-reducing die or 1%
A method for producing a long, high-precision ultra-fine steel wire, which comprises finally passing a skin-pass die having a die diameter having the following surface reduction rate. 3. A final reduction for determining a substantially final wire diameter in a step of manufacturing an ultrafine steel wire by a multistage die drawing method after intermediate heat treatment of a steel wire material of an intermediate size to be used for finishing ultrafine wire drawing. A surface die is continuously provided with a rotating mechanism, and the die is continuously or intermittently rotated during wire drawing for continuous wire drawing, and the surface area is equal to or less than 1% of the inner diameter of the rotary die. A method for producing a long, high-precision, ultra-fine steel wire, which comprises finally passing a skin-pass die having a die diameter of a certain ratio.