JPH06328124A - Diamond die for wire drawing - Google Patents

Abstract

PURPOSE:To provide a diamond die for a wire which can obtain the wire suitable in the supply quantity lubricant and small in friction between the wire and the die, free from the surface flaws of the wire caused by the die damage when the wire is drawn and is excellent in feeding property of the wire at a welding time even when a large quantity of the wire is drawn at a high speed. CONSTITUTION:In the diamond die for wire drawing composed of an entrance and an approach of an introduction part, reduction, a bearing and a back relief of a wire drawing part and an exit of an outlet part, the length of the bearing is made 0.30D-0.45Dmm to the inner diameter D(mm), the approach angle alphais made 6-10 deg., the angle of the back reef beta is made 45-60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire drawing die using a hard sintered body containing diamond as a main component, and more particularly to a diamond die suitable for wire drawing at high speed. .

[0002]

2. Description of the Related Art In recent years, the automation and labor saving of welding have been promoted, and the technological progress of semi-automatic welding and full-automatic welding is remarkable,
The demand for welding steel wire (hereinafter, referred to as wire) used with this trend tends to increase year by year. In such a situation, it is necessary to economically and efficiently produce a wire and to provide the wire with a wire having good feedability and stable quality during use (during welding) to the market. However, if the capacity of the production equipment is increased and wire drawing is performed to a wire diameter of 0.8 to 2.0 mm at a high speed of 1000 m / min or more,
Roughness of the dies occurs, and the dies are frequently replaced, resulting in poor economic efficiency and production of stable quality wire.

Therefore, in order to cope with high-speed wire drawing in recent years,
Diamond wire dies, which are used for wire drawing of wire materials having high melting points such as tungsten and molybdenum, have come to be used for wire drawing. However, in a commercially available diamond die defined in JIS B4133, an appropriate amount of lubricant is not brought in during wire drawing at high speed, the friction between the wire and the die becomes large, the die becomes rough, and the wire surface is scratched. Occurs, shortening the die life. Furthermore, in order to improve the wire feedability during welding,
As disclosed in Japanese Unexamined Patent Publication No. 398, when an appropriate amount of lubricant is applied to the wire surface in the final skin pass, the amount of lubricant applied is reduced because wire drawing is performed at a high speed, resulting in poor wire feedability during welding. There is also.

[0004]

Therefore, according to the present invention, even if a large amount of wire is drawn at a high speed, the amount of the lubricant brought in is appropriate, the friction between the wire and the die during wire drawing is small, and wire surface scratches due to die roughening occur. It is an object of the present invention to provide a diamond die for wire drawing that can obtain a wire that does not have a good wire feeding property during welding.

[0005]

In order to achieve the above-mentioned object, the present invention is directed to an entrance a of an introduction part A, an approach b, a reduction c of a wire drawing part B, a bearing d and a back leaf e, and an exit part C. In the wire drawing diamond die consisting of the exit f, the length dl of the bearing d
Is set to 0.30D to 0.45Dmm with respect to the inner diameter D (mm), the approach angle α is set to 6 to 10 °, and the back leaf angle β is set to 45 to 60 °.

[0006]

The present inventors have made various studies on the shape of the diamond die shown in FIG. 1 and the influence on the wire drawability of the wire at a high speed of 1000 m / min or more and the quality after wire drawing. As a result, by limiting the length dl of the bearing d, the approach angle α, and the back leaf angle β to predetermined ranges, there is no wire surface flaw due to roughness of the die during wire drawing, the die life is long, and an appropriate amount of lubricant is used. It has been found that a stable quality wire having good wire feedability can be obtained. The reasons for limitation are described below.

First, the bearing length dl needs to be 0.30 D to 0.45 D mm with respect to the inner diameter D (mm) of the bearing. If it is less than 0.30 Dmm, the surface of the wire is damaged due to the roughening of the die, the life of the die is short, and it is necessary to replace the die frequently, resulting in poor production efficiency and economical efficiency. On the other hand, if the bearing length d exceeds 0.45 Dmm, the amount of lubricant adhering to the wire surface decreases with the deterioration of the lubricant carry-in, and the wire feedability during welding deteriorates.

Next, the approach angle α needs to be 6 to 10 °. When the angle is less than 6 °, the crimping distance between the wire and the die becomes long, the die becomes rough, and the wire surface is damaged. When the approach angle α exceeds 10 °, the amount of lubricant brought in is small, the friction between the wire and the die is large, the wire surface is scratched due to the roughness of the die, and the amount of lubricant attached to the wire is reduced. , The wire feedability during welding becomes poor.

The angle β of the back leaf must be 45-60 °. When the angle is less than 45 °, the amount of lubricant taken out is small, the amount of lubricant adhered to the wire surface is small, and the wire feedability during welding becomes poor. If it exceeds 60 °, the strength of the bearing becomes weak and may be damaged, resulting in a shorter die life.

[0010]

The present invention will be described in more detail with reference to the following examples. First, YGW specified in JIS Z3312
11 solid wires drawn and plated to a diameter of 3.2 mm were continuously drawn with 15 dies up to a product diameter of 1.2 mm. The dies used were prototype diamond dies with various shapes and sizes shown in Table 1. The area reduction ratio of wire drawing in each die was 10 to 14%, and the linear velocity at the final die exit was 12%.
The wire was drawn at 00 m / min. In each test example, the length of the die with respect to the bearing diameter, the approach angle, and the back leaf angle were constant for 15 pieces.

In each test example, the die was evaluated by the wire 50.
Tons of wire up to a product diameter of 1.2 mm and wound on a 20 kg winding spool. The wire drawability at that time depends on the presence or absence of scratches on the wire surface, the amount of lubricant adhered to the product diameter, and the welding device shown in Fig. 2. Welded and used to investigate the wire feedability.

When the die was rough during wire drawing and the surface of the wire was scratched or the die was damaged, wire drawing was stopped at that point. As the wire drawing lubricant, one containing vegetable oil and an anion activator as main components was used. The amount of lubricant adhering to the product diameter is 0.4 to 1.2 g per 10 kg of wire, which is good for wire feedability during welding and defect resistance (pits, blowholes). Regarding the wire feeding property, for the purpose of increasing the feeding resistance, the wire pulled out from the spool 2 was fed by the feeding motor 3 to the 6 m conduit cable 1 provided with the loop 2 rotation of 200 mm in diameter and fed to the torch 4. . The welding conditions at that time are as follows. Welding current 300A welding voltage 30V welding speed 35 cm / min shield gas CO ₂ 20 liters / min welding method bead-on-plate

The wire feedability was examined by measuring the armature current of the feed motor 3. If the armature current exceeds 3.5 A, the wire feedability will be poor. The results are summarized in Table 1.

[0014]

[Table 1]

In Table 1, the test No. Test Nos. 1 to 6 were drawn by the diamond die of the present invention. 7-
12 is a comparative example. Test No. 1 using the die of the present invention.
Nos. 1 to 6 have no wire surface scratches due to the roughness of the die during wire drawing, have a proper amount of lubricant, and have good wire feedability.
The result was extremely satisfactory.

In the comparative example, the test No. No. 7 has a long length with respect to the bearing diameter of the die, and therefore the test No. 12
Had a small back leaf angle, the amount of lubricant adhered to the wire surface was small, the armature current was high during welding, and the wire feedability was poor. Test No. Test No. 8 has a short length with respect to the bearing diameter of the die, so that the test No. No. 9 has a large approach angle, so test No. 9 was also used. In No. 10, since the approach angle was small, the die was rough and scratches were generated on the wire surface, so wire drawing was stopped. Test No. 11 is
Since the back leaf angle was large, the die was damaged during wire drawing, so wire drawing was stopped.

[0017]

As described in detail above, according to the diamond die for wire drawing of the present invention, even if a large amount of wire is drawn at high speed,
We can provide a welding wire that has no damage on the wire surface due to die roughening, has an appropriate lubricant carry-in amount, and has good wire drawability and wire feedability during welding, making a major contribution to improving the productivity of high-quality wires. To do.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the shape of a diamond die.

FIG. 2 is a view showing a welding device used in an embodiment of the present invention.

[Explanation of symbols]

 A introduction part B wire drawing part C exit part D bearing inner diameter a entrance b approach c reduction d bearing dl bearing length e back leaf f exit α approach angle β back leaf angle 1 conduit cable 2 spool 3 feed motor 4 torch

Claims (1)

[Claims] 1. An entrance of an introduction part, an approach, a reduction of a wire drawing part, a bearing and a back leaf,
In the diamond die consisting of the exit exit, the bearing length is 0.30 with respect to the inner diameter D (mm).
D-0.45Dmm, the approach angle is 6-10 °, and the back leaf angle is 45-60 °. A diamond die for wire drawing.