JPH0522561U - Spinneret - Google Patents

Abstract

(57) [Summary] [Structure] In a spinneret formed by forming a spinning hole in ceramics, cermet, or cemented carbide, the surface roughness of the inner wall surface of the spinning hole is 0.5 to 4 s. [Effect] It is possible to significantly extend the cycle of the cleaning work for scraping off the carbide adhered to the lower surface of the spinneret. As a result, the equipment operating rate of the spinning machine can be increased and productivity can be improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a spinneret used for spinning synthetic fibers.

[0002]

[Prior Art]

 As shown in FIG. 1, a general shape of a spinneret used for spinning synthetic fibers is a disk-shaped spinneret body 10 in which a large number of introducing holes 11 and spinning holes 12 communicating therewith are formed. For example, in the case of melt spinning, the molten stock solution is spun from the spinning hole 12 to obtain a synthetic fiber having a predetermined shape and thickness. In addition, since carbide of the molten stock solution adheres to the lower surface 13 on the spinning hole 12 side during use and causes thread breakage, use a spatula-like jig to scrape off the adhered material on the lower surface 13 at any time. I was doing cleaning work.

A metal material such as stainless steel has been used as the material of the die body 10, but carbide of the molten stock solution is liable to adhere, requires cleaning work in a short period of time, and has low wear resistance. Therefore, there was a problem that the life was short.

Therefore, ceramics, cermet, or cemented carbide has come to be used as the material of the die body 10. Further, as shown in FIG. 2, a nozzle piece 14 made of ceramics, cermet, cemented carbide or the like is provided only in the vicinity of the introduction hole 11 and the spinning hole 12, and the nozzle piece 14 is attached to the metal die body 10. Some of them have been disclosed (see JP-A-58-76512).

As described above, in the spinneret using ceramics, cermet, or cemented carbide, since the wettability of the material is poor, it is difficult for the carbide of the molten stock solution to adhere to the lower surface 13, and the adhered material on the lower surface 13 is scraped off. The cleaning cycle was longer than the metal spinneret.

[0006]

[Problems to be solved by the device]

 However, in the spinneret using the above-mentioned ceramics, cermet, or cemented carbide, the inner wall surface of the spinning hole 12 is polished so that the surface roughness becomes a smooth surface of 0.4 s or less. Therefore, the flow of the molten undiluted solution in the spinning hole 12 causes a difference in flow velocity between the vicinity of the inner wall surface and the central portion, and as a result, the undiluted molten solution discharged from the spinning hole 12 adheres to the lower surface 13. There was a problem that it was easy.

[0007]

[Means for Solving the Problems]

 In view of the above, the present invention relates to a spinneret made of ceramics, cermet, and cemented carbide with spinning holes, wherein the inner wall surface of the spinning hole has a surface roughness of 0.5 to 4 s. is there. In this way, since the inner wall surface of the spinning hole is rough, the difference in the flow velocity of the molten stock solution between the vicinity of the wall surface and the central part is small, and the molten stock solution from the spinning hole does not easily adhere to the lower surface. . As a result, the period of the cleaning work for scraping off the deposits on the lower surface becomes longer.

Further, in order to make the inner wall surface of the spinning hole have the above-mentioned surface roughness, an electrolytic solution having a relatively low concentration may be used and the processing may be performed by electrolytic polishing.

[0009]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings (for convenience, the same drawings as the conventional example will be used).

The spinning spinneret shown in FIG. 1 comprises a disk-shaped spinneret body 10 having a large number of introduction holes 11 and spinning holes 12 communicating therewith. For example, in the case of melt spinning, melt spinning is performed. By spinning the stock solution through the spinning hole 12, a synthetic fiber having a predetermined shape and thickness was obtained. The base body 10 is integrally formed of ceramics, thermite, or cemented carbide, and the inner wall surface of the spinning hole 12 is a relatively rough surface of 0.5 to 4 s.

In another embodiment, as shown in FIG. 2, only the vicinity of the introduction hole 11 and the spinning hole 12 is a nozzle piece 14 made of ceramics, cermet, cemented carbide or the like, and the nozzle piece 14 is It may have a structure attached to the metal cap body 10, and in this case also, the inner wall surface of the spinning hole 12 is a relatively rough surface of 0.5 to 4 s.

As described above, various methods are conceivable for making the inner wall surface of the spinning hole 12 a relatively rough surface of 0.5 to 4 s, but electrolytic polishing is particularly preferable. For example, in the case of the example shown in FIG. 2, first, as shown in FIG. 3, a nozzle piece 14 is formed in a shape having a spinning hole 12, and the inner wall surface of this spinning hole 12 is polished to obtain a predetermined inner diameter d. After that, when the spinning hole 12 portion is dipped in an electrolytic solution and a voltage is applied between the electrode in the electrolytic solution and the nozzle piece 14, the surface of the nozzle piece 14 may be roughened depending on the amount of current and the energization time. it can. With this method, it is easy to adjust the surface roughness to a predetermined value, and the accuracy of the inner diameter d is not deteriorated. In electrolytic polishing, the edge portion of the lower end of the spinning hole 12 is easily processed. Therefore, it is desirable to adjust the length 1 of the spinning hole 12 by polishing the lower end surface after electrolytic polishing.

In general, electrolytic polishing is used as a method of roughening a plane surface such as a square plate, but the present invention utilizes the fact that the reaction amount of processing is related to current and time, and in particular, This processing method was used to roughen the inner wall of the spinning hole 12, which requires high precision. Further, in the case of this processing method, the required accuracy can be easily satisfied because no reaction occurs when the power is turned off.

Note that the nozzle piece 14 must be made of a conductive material in order to perform electrolytic polishing, and when ceramics is used, conductive ceramics such as silicon carbide ceramics and aluminum ceramics containing TiC are used.

Experimental Example 1 First, the following tests were carried out with respect to the surface roughness of the inner wall surface of the spinning hole 12 and the cycle of the cleaning operation for scraping off the deposits on the lower surface 13.

A spinning test was conducted by changing the surface roughness of the inner wall surface of the spinning hole 12 variously, and the running time until the cleaning work for scraping off the deposits on the lower surface 13 was required for each was determined. The result is as shown in FIG.

As a result, there is a close relationship between the surface roughness of the inner wall surface of the spinning hole 12 and the running time. In the conventional spinneret having a surface roughness of 0.2 s, the running time was about 6 hours. By setting the surface roughness of the inner wall surface to 0.5 to 4 s, the running time could be significantly extended to 20 hours or more, and particularly about 1 s, the running time was 30 hours or more, which was excellent. This is because if the inner wall surface of the spinning hole 12 is appropriately rough, the molten stock solution during spinning is less likely to adhere, and the difference in the outflow velocity between the central portion and the portion near the inner wall is small.

Experimental Example 2 Next, a processing experiment of the inner wall surface of the spinning hole by electrolytic polishing was conducted.

Processing was performed so that the surface roughness of the inner wall surface of the spinning hole 12 of the nozzle piece 14 having the shape shown in FIG. 3 was Rma x1s. The nozzle piece 14 was made of a TiC-TiN cermet, and had a diameter of 6 mm, a diameter d of the spinning hole 12 of 0.2 mm, and a length 1 of the spinning hole 12 of 0.3 mm.

A dilute nitric acid solution having a concentration of 2%, 5%, and 7.5% was prepared as an electrolytic solution, and was adjusted to 0. By changing the surface roughness of the inner wall surface of the spinning hole 12 (Fig. 5), the diameter d (Fig. 6), and the length l (Fig. 7) with the electropolishing time by applying a direct current of 2A. confirmed. The results are as shown in FIGS.

From FIG. 5, when electrolytic polishing is performed for about 15 minutes with a dilute nitric acid solution having a concentration of 2% and 5% and for about 5 minutes with a dilute nitric acid solution having a concentration of 7.5%, the surface roughness Rmax1s can be obtained. did it. However, as shown in FIGS. 7 and 8, in the case of dilute nitric acid solution having a concentration of 2% and 5%, the processing time is long, but the required accuracy is easily satisfied because the dimensional change amount of the inner diameter d and the length l is small. be able to. Compared with this, in the case of a dilute nitric acid solution with a concentration of 7.5%, the processing time is short, but the reaction is so vigorous that the dimensional change of the inner diameter d and the length l is large, so it is difficult to maintain accuracy. . Therefore, it is difficult to satisfy the required accuracy.

From the above results, it can be understood that the inner wall surface of the spinning hole can be processed to 1 s or more while maintaining excellent accuracy by performing electrolytic polishing with the concentration of the dilute nitric acid solution being 5% or less.

Experimental Example 3 The same experiment as in Experimental Example 2 was conducted by changing the electrolytic solution from a dilute nitric acid solution to a nickel chloride solution. The results are shown in Fig. 8.

From FIG. 8, it is difficult to process with high accuracy in the case of a nickel chloride solution having a concentration exceeding 5%, but by using a nickel chloride solution having a concentration of 5% or less, it is possible to perform spinning while maintaining excellent accuracy. It can be seen that the inner wall surface of the hole can be processed for 1 s or more.

Further, in these embodiments, the machining amount is also related to the magnitude of the current, and the larger the current value, the larger the machining amount. However, as a result of various experiments, when the current value is 1 A or more, the accuracy of the inner diameter d deteriorates drastically, so that the current value of 1 A or less is preferable.

Comparative Example On the other hand, other processing was performed as compared with the electrolytic polishing processing.

First, the inner wall surface of the spinning hole 12 was processed using diamond abrasive grains. As shown in FIG. 9, the surface roughness can be increased by enlarging the diamond abrasive grains, but it is difficult to process for 1 s or more, and the variation in the surface roughness is large. I couldn't finish it evenly.

Next, electrolytic polishing was performed using a potassium hydroxide solution as an electrolytic solution. As the result is shown in FIG. 10, it could not be processed at all. Therefore, it is necessary to use a nitric acid solution or a nickel chloride solution as the electrolytic solution for electrolytic polishing.

[0029]

[Effect of the device]

 As described above, according to the present invention, in a spinneret formed by forming a spinning hole in ceramics, cermet, or cemented carbide, the surface roughness of the inner wall surface of the spinning hole is 0.5 to 4s. As a result, the period of cleaning work for scraping off the carbide adhered to the lower surface of the spinneret can be significantly extended. As a result, the equipment utilization rate of the spinning machine can be increased and productivity can be improved.

Further, such a spinneret is easily processed so as to have a predetermined surface roughness while maintaining excellent dimensional accuracy by using an electrolytic solution having a relatively low concentration and processing by electrolytic polishing. Can be processed into As a result, the manufacturing yield of the spinneret can be improved.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing a spinneret according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a spinneret according to an embodiment of the present invention.

FIG. 3 is a sectional view showing only the nozzle piece in FIG.

FIG. 4 is a graph showing the relationship between the surface roughness of the inner surface of the spinning hole of the spinneret and the running time until the deposits on the lower surface are removed.

FIG. 5 is a graph showing the relationship between electrolytic polishing time and surface roughness.

FIG. 6 is a graph showing the relationship between the electropolishing time and the amount of change in the spinning hole inner diameter d.

FIG. 7 is a graph showing the relationship between the electrolytic polishing time and the amount of change in the spinning hole length l.

FIG. 8 is a graph showing the relationship between electrolytic polishing time and surface roughness when a nickel chloride solution is used as the electrolytic solution.

FIG. 9 is a graph showing the relationship between abrasive grain size and surface roughness when diamond abrasive grains are used.

FIG. 10 is a graph showing the relationship between electrolytic polishing time and surface roughness when a potassium hydroxide solution is used as the electrolytic solution.

[Explanation of symbols]

 10 ・ ・ Base body 11 ・ ・ Introduction hole 12 ・ ・ Spinning hole 13 ・ ・ Bottom surface 14 ・ ・ Nozzle piece

Claims (1)

[Scope of utility model registration request] 1. A spinneret characterized in that a spinning hole is formed in ceramics, cermet or cemented carbide, and the inner wall surface of the spinning hole has a surface roughness of 0.5 to 4 s.