JPH028808B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for drilling holes in a spinneret.

Traditionally, durable cemented carbide has been used for punch tools for punching spinnerets made of stainless steel, gold-platinum alloys, etc., but among these, ferrite-based ones require tens of thousands of round holes. When drilling holes in or austenitic stainless steel material (normal plate thickness around 0.5 mm), the tip of the punch tool breaks after drilling about 1,000 to 2,000 holes, and the punch tool has to be replaced with a new one many times during the work. There was a drawback that it had to be done. In addition, the inner wall of the hole processed by the time of breakage becomes a dull, rough surface, and this roughens the surface of the spun yarn, resulting in a disadvantage that the quality of the spinneret deteriorates.

The reason why the tip of the punch tool is damaged as described above is that a seizure phenomenon occurs between the punch tool 1 made of cemented carbide and the stainless steel material 2 during drilling, as shown in Figure 1a, and the tip of the punch tool 1 is damaged. Part 1
As shown in FIG.
After drilling ~2000 holes, the tip 1a of the punch tool 1 completely adheres to the inner wall of the hole.
This is because when the punch tool 1 rises, the tip portion 1a is tensile and breaks as shown in FIG. 1b.

For this reason, in the past, in order to prevent the tip 1a of the punch tool 1 from seizing, lubricant oil 3 was applied to the top surface of the stainless steel material 2 as shown in Figure 3a, but in order to increase mass production efficiency, the drilling speed was If you make the process faster or approach the final process of drilling, the third
As shown in FIG. b, it becomes difficult for the lubricating oil 3 to flow up to the tip 1a of the punch tool 1, so that the anti-seizure effect is not sufficiently exhibited.

The present invention has been made in view of the above circumstances, and is intended to make holes using a punch tool for making holes in a spinneret, which does not cause the sticking phenomenon and does not cause breakage of the tip.

The method for forming holes in a spinneret according to the present invention is a method in which a lubricating oil film is formed on the top surface of a stainless steel spinneret and then holes are formed using a cemented carbide punch tool, whereby a TiN ion plating film of 0.03 to 0.2 μm is formed. This method is characterized in that the holes are made using a punch tool that has been prepared by the manufacturer.

In the punch tool for making holes in the spinneret of the present invention, as shown in FIG.
The reason for coating TiN film 4 is that
This is because the coefficient of friction is small, and when punching the stainless steel material 2, seizure can be prevented and breakage of the tip of the punch tool can be avoided. In addition, the TiN film 4
The reason why the coating was applied using the ion plating method is that the bonding strength with the punch tool 1 made of cemented carbide is sufficient and it will not peel off during the drilling process, and this is the reason why the coating is applied using other sputtering or vapor deposition methods. This is because the bonding strength between the punch tool 1 made of cemented carbide and the punch tool 1 is insufficient, and the punch tool 1 easily peels off during drilling. Furthermore, the above
The reason why the thickness of the TiN film 4 was limited to 0.03 to 0.2 μm is as follows.
As shown in Figure 5, if it is less than 0.03 μm, it will be almost the same as the base cemented carbide, and there will be no seizure prevention effect, and if it exceeds 0.2 μm, TiN crystal grains will grow due to the frictional heat during drilling. Otherwise, the surface of the coating film will become rough, the perforated surface 5 of the spinneret will not be glossy, and the anti-seizure effect will be lost.

In the case of a punch tool that strikes approximately 0.5 mm thick stainless steel material at a speed of 1 to 5 pieces per second, if the temperature at the tip of the punch tool rises too much (over 400°C), the TiN coating film may be damaged due to the small size of the punch tool. peels off. In the present invention, since seizure is prevented, the temperature of the punch tool tip does not rise, and since it is cooled by lubricating oil, the temperature of the punch tool tip does not rise too much.

Next, in order to clarify the effects of the present invention, specific embodiments and conventional examples thereof will be described.

Example Made of cemented carbide, taper angle 30 degrees, length 0.9 mm,
Film thicknesses of 0.01 μm, 0.05 μm, 0.08 μm, 0.1 μm,
0.15μm, 0.20μm, 0.50μm, 0.80μm, 1.0μm
A TiN film 4 was coated by an ion plating method.

In addition, 0.01μm, 0.50μm, 0.80μm and 1.0μm
TiN ion plating film is shown for comparison.

When a spinneret was manufactured by punching holes in an austenitic stainless steel material 2 at a rate of 2 to 4 holes per second using each punch tool 1, the film thickness was
As shown in the graph in Fig. 5, each punch tool 1 with a diameter of 0.05 to 0.2 μm prevents seizure even after drilling more than 2000 holes, does not break the tip 1a, and has a significantly extended breakage life. There is. Moreover, the perforated surface 5 of the spinneret was glossy and a good quality spinneret was obtained.

Conventional example Made of cemented carbide with a taper angle of 30 degrees and a length of 0.9 mm.
Punch holes are punched into an austenitic stainless steel material 2 each having a thickness of 0.5 mm at a rate of 2 to 4 holes per second using 10 conical hole punch tools 1 each having a diameter of 0.8 mm and shown in Fig. 1a. When a spinneret was manufactured using the same method, each punch tool 1 suffered from seizure after punching 1,000 to 2,000 holes and the tip portion 1a broke, resulting in extremely short breakage life. As a result, the punch tool had to be replaced many times during the process of punching 10,000 holes. Further, the perforated surface 5 was a rough surface with no luster, and a spinneret of poor quality was obtained.

Although the above embodiment describes the case where holes are made in the austenitic stainless steel material 2, the present invention is not limited to this, and the hole punch tool 1 of the present invention can be used as described above even when holes are made in ferritic stainless steel. Similarly, burn-in is prevented, the tip portion 1a does not break, and its lifespan is extended.

As detailed above, the drilling method according to the present invention includes:
Even after drilling more than 2000 holes in stainless steel spinneret material, the film thickness is 0.03 to 0.2 μm.
Since it is coated with a TiN film, there will be no burn-in and the TiN film will not peel off.
Therefore, the tip part does not break, and the service life is significantly extended. In addition, the processed surface of the spinneret drilled using the hole punching method of the present invention is smooth and glossy.
There are effects such as obtaining a spinneret of good quality.

[Brief explanation of drawings]

Fig. 1a is a cross-sectional view showing the state of hole-making using a conventional spinneret punch tool, Fig. 1b is a cross-sectional view showing the state in which the tip of the hole-making punch tool is broken, and Fig. 2 3 is an enlarged cross-sectional view showing a state in which deposits are welded to the tip of the punch tool for hole-drilling.
Figures a and b are cross-sectional views showing the process of applying lubricating oil to the top surface of a stainless steel material and punching a hole using a hole punch tool, and Figure 4 is a hole punching process using the spinneret hole punching method according to the present invention. FIG. 5 is a graph showing the relationship between the thickness of the TiN film of the punch tool and the rupture life in the hole-drilling method of the present invention. 1... Punch tool, 1a... Tip of punch tool, 2
... Stainless steel material, 2a... Deposit, 3... Lubricating oil,
4...TiN film, 5...Drilled surface.

Claims (1)

[Claims] 1 In the method of forming a lubricating oil film on the top surface of a stainless steel spinneret and then punching a hole with a cemented carbide punch tool, a punch tool on which a 0.03 to 0.2 μm TiN ion plating film is formed is used to punch the hole. A method for making holes in a spinneret characterized by the following.