JPS60111716A - Manufacture of metallic wire rod - Google Patents

Abstract

PURPOSE:To guarantee characteristics of all products basing on a drawing force and to improve remarkably the productivity by measuring continuously the drawing force of a material to be worked to be passed through a die and preventing its breakage by controlling the drawing force to the value less than or equal to the prescribed yielding strength of the material. CONSTITUTION:The drawing force of a material (a) to be worked is detected as the strain quantity of a resistance wire by providing a load cell 3 housing a electric-resistance strain gauge to the space between a die 1 for drawing the material (a) and a die holder 2, and the strain quantity is converted into an output in a range of about 0-1V by an amplifier 4 and is simultaneously converted into a drawing force kg to indicate it by a direct-reading meter 5 thereby recording it in a recorder 6. In this way, by controlling the drawing force to <=0.2% yielding strength of the material, the breakage of material is prevented and the characteristics of all products are guaranteed by the magnitude of drawing force. Thus the manpower for sampling inspection is saved and the variance of material quality due to the breakage during working is eliminated to improve the productivity remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a metal wire, and in particular, it prevents breakage of the workpiece material during wire drawing and improves the properties (tensile strength, elongation, conductivity) of the wire drawn product. This system is designed to guarantee the full rate (rate).

In general, metal wires, especially Cu wires and 8 (wires) used as conductive materials, are made by a wide wire drawing process through a die, and in order to guarantee their performance, a portion is extracted from each product to check the tensile strength, elongation, etc. The electrical conductivity is measured.However, although the cost required for this measurement is enormous, it is impossible to guarantee the quality of all wires due to sampling inspections.Furthermore, wire breaks often occur during the wire drawing process. However, although this not only hinders productivity but also causes variations in product characteristics, it has not been possible to accurately determine the cause of the wire breakage.

In view of this, as a result of various studies, the present invention has found that wire breakage during wire drawing is mostly due to the fact that the magnitude of the drawing force cannot be clearly grasped. As a result of further study, we established a method for measuring the pulling force during wire drawing, measured the drawing force during wire drawing, and controlled it. We have developed a method for manufacturing metal wire that prevents wire breakage in the workpiece and guarantees the characteristics of all products.

That is, the present invention continuously measures the drawing force of the workpiece material being drawn through a die in the wire drawing process for producing metal wire, and controls the drawing force to below 0.2% yield strength of the workpiece hard material. It is characterized by preventing wire breakage and guaranteeing the characteristics of the product based on the magnitude of the pulling force.

In order to measure the pulling force of a workpiece that is pulled through a die in the present invention, as shown in Fig. A load cell (3) with a built-in meter is installed, and a die (1) is installed.
The pulling force of the workpiece (a) being handled through the load cell (3) is detected as the amount of strain in the resistance wires arranged in the load cell (3), and this is converted into an output of 0 to 1 V by the amplifier (4), and the pulling force ( K9) is displayed on the direct reading meter (5>) and recorded on the recorder (6).In this way, the present invention continuously detects the pulling force of the workpiece being pulled through the die in the wire drawing process. By controlling the pulling force to less than 0.2% proof stress of the hard material to be processed, breakage of the material to be processed is prevented.Furthermore, the pulling force is continuously recorded and the product characteristics can be determined from the pulling force. This is a guarantee for all quantities.

However, the reason why the pulling force is controlled to be less than the 0.2% yield strength of the hardwood to be processed is to prevent wire breakage as mentioned above and to prevent product variations. What is guaranteed is that a pulling force of 0.2% proof stress or less corresponds to the characteristics of the product, so the relationship between the pulling force, tensile strength, elongation, conductivity, etc. of various metal wires is experimentally determined in advance. Then, the drawing process is performed using a drawing force according to predetermined characteristics, thereby guaranteeing the characteristics of all products.

The load cell can be installed at any position on each die during continuous wire drawing, but it is preferable to install it on a die at a position where the drawing force is representative of the characteristics of the product, and the drawing force can be controlled at one die. This can be easily achieved by lowering the area reduction rate per hit and adjusting the wire drawing speed.

The present invention will be described in detail below with reference to Examples.

A wire rod with a diameter of 8.0 mm was processed into a wire rod with a diameter of 4.0 mm using a continuous wire drawing machine according to the conventional method.
The load cell shown in the figure was placed, wire drawing was performed with various drawing forces, and the relationship between drawing force and wire breakage was investigated. As a result, as shown in Figure 2, the pulling force was increased (0.2% yield strength of hardwood (about 495
It can be seen that when the weight exceeds 1 kg), the number of wire breaks increases significantly. The dotted line in the figure indicates A (hard wood), and the solid line indicates A (soft wood).

Next, wires A and e were drawn using the same wire drawing machine with various drawing forces, and various properties of the obtained wire rods were measured. The results are shown in Figures 3 (a), (b), and (c).

(a) is the pulling force and conductivity, (b) is the pulling force and tensile strength,
(C) shows the relationship between drawing force and elongation.As is clear from the figure, there is a specific relationship between the drawing force of the workpiece during wire drawing and the properties of the product, and the drawing force can be controlled. It can be seen that by doing so, a product with desired characteristics can be obtained.

To the above (although the description has been made regarding wire rods, the present invention is not limited to this, and similar results can be obtained with Cu wire and other various wire rods.

As described above, according to the manufacturing method of the present invention, there is no need to measure the characteristics of the product by handling and inspecting a part of the product as in the past, and the quality of the entire product can be guaranteed by the pulling force. It is possible to save labor related to inspections, etc. In addition, by preventing wire breakage during wire drawing, productivity is significantly improved and quality variations due to wire breakage are eliminated, resulting in significant industrial effects.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing a method for measuring the pulling force of a workpiece in the wire drawing process of the present invention, Fig. 2 is an explanatory diagram showing the relationship between drawing force and wire breakage, Figs. 3 (a), (b), (C) shows the relationship between pulling force and product characteristics, (A) shows the relationship between pulling force and electrical conductivity, (B) shows the relationship between pulling force and tensile strength, and (C) shows the relationship between pulling force and elongation. It is an explanatory diagram. a, Workpiece material 1, Dice 2, Dice holder 3, Load cell 4, Amplifier 5, Direct reading meter-6, Recorder agent Patent attorney Seibi Minoura 1゛L゛,・ri

Claims (2)

[Claims] (1) In the wire drawing process for manufacturing metal wire, the drawing force of the workpiece material being drawn through a die is continuously measured, and the drawing force is controlled to be less than 0.2% yield strength of the workpiece hard material to break the wire. The characteristics of the product (tensile strength, tensile strength,
A method for producing metal wire, which is characterized by guaranteeing the elongation and electrical conductivity of all products. (2) A load cell with a built-in resistance wire strain meter is installed between the die through which the hpT material is passed and the die holder, and the pull-out force of the workpiece is detected as the amount of strain in the resistance wire, and this is converted into the pull-out force. Claim 1 wherein the recorded values are displayed on a direct reading meter and recorded on a recorder, and the characteristics of the product are characterized by the recorded values.
The method for manufacturing the metal wire described in Section 1.