JPH0424207A - Spinneret - Google Patents

Abstract

PURPOSE:To provide a spinneret having a highly sealed connecting portion in a good yield by inserting a nozzle piece comprising a ceramics, cermet or carbide alloy into the attaching hole of a metal-made spinneret main body and brazing the inserted nozzle piece and the main body in the major axis direction partially around all the periphery. CONSTITUTION:A nozzle piece 1 comprising a ceramics, cermet or carbide alloy and having a feeding hole 1a and a spinning hole 1b is inserted into an attaching hole 2a formed in a spinneret 2, and a step portion 1c of the nozzle piece 1 on the tip side thereof in the longitudinal direction is filled and brazed with a brazing material partially around the whole periphery thereof to provide the objective spinneret. Since the brazing material is filled over the whole periphery of a space between the nozzle piece and the spinneret main body 2, the connecting portion can perfectly be sealed, and even when a dimensional difference is produced in the major axis direction of the nozzle piece 1 due to a difference between the thermal expansion of the nozzle piece 1 and the spinneret main body 2, any crack is not produced because the brazing portion is short.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a spinneret used for spinning synthetic fibers.

[Conventional technology]

The spinneret used for spinning synthetic fibers, as shown in FIG. 3, has a disc-shaped spinneret body lO formed with a large number of introduction holes 11 and a spinning hole 12 communicating with the introduction holes 11.
For example, in the case of melt spinning, a synthetic fiber having a predetermined shape and thickness is obtained by spinning a molten stock solution through a spinning hole 12.

As the material of the mouthpiece body 1O, metal materials such as stainless steel, ceramics, cermets, cemented carbide, etc. have been used.

In addition, the introduction hole 11. There was also a structure in which a nozzle piece made of ceramic, cermet, or cemented carbide was used only in the vicinity of the spinning hole 12, and this nozzle piece was attached to a metal mouthpiece body IO (see Japanese Patent Application Laid-Open No. 76512/1983). .

[Issues with conventional technology]

Spinnerets made of metal materials such as stainless steel have problems in that carbides from the molten stock solution tend to adhere to them, requiring cleaning work in a short period of time, and their lifespan is short due to low wear resistance.

In addition, with a spinneret integrally formed from a hard material such as ceramics, cermet, or cemented carbide, it is difficult to accurately form a large number of spinning holes 12, resulting in a very low manufacturing yield and high cost. It was also expensive.

Therefore, it was difficult to determine the best structure for attaching a nozzle piece made of ceramics, cermet, cemented carbide, etc. to a metal mouthpiece body, or in this case, how to connect the nozzle piece and the mouthpiece body. For example, if the joint is simply made by firing, press-fitting, mechanical joining, etc., the joined part may not be completely sealed and the molten liquid will leak out, and if brazing is used, the main body of the cap will be damaged. Because the coefficient of thermal expansion is high, there was a problem in that large stress was applied to the nozzle piece side during cooling after brazing, resulting in cracks.

[Means to solve the problem]

In view of the above, the present invention has been developed by brazing a nozzle piece made of ceramics, cermet, or cemented carbide to a metal mouthpiece body to a length of 3 to 7 mm, partially in the longitudinal direction, and completely in this part. It is soldered all the way around.

C Example] Embodiments of the present invention will be described below with reference to the drawings.

The spinneret shown in FIG. 1 includes a nozzle piece 1 having an introduction hole 1a and a spinning hole 1b, and a mounting hole 2 formed in a spinneret body 2.
It is arranged and combined within a. This bond structure is
The step portion 1c prevents the nozzle piece 1 from coming off, and the solder material 3 is filled only on the tip side of the step portion 1c, and the nozzle piece 1 is joined by brazing.

Further, as another embodiment (not shown), the step portion 1c may be omitted, the nozzle piece 1 may have a straight shape, and only the tip portion of the nozzle piece 1 may be brazed. Furthermore, it is also possible to braze only the rear end side of the nozzle piece 1, or to braze only the front end side and the rear end side.

In addition, in FIG. 1, only one nozzle piece 1 is shown, or a large number of nozzle pieces 1 are similarly connected to the base body 2.

As shown in Table 1, the material of the nozzle piece l is ceramics such as alumina, zirconia, silicon carbide, silicon nitride, cermet, cemented carbide, or the like.

The above-mentioned cermets include carbides, nitrides, or carbonitrides (TiC, TiN) of transition metals in groups 4a and 5a.
, T1CN, NbC, TaC, etc.) and iron group metals (Fe, Ni, Co), and is a heat-resistant sintered body with electrical conductivity.

In addition, the material of the cap body 2 may be any general metal material, or may be made of stainless steel, which has excellent corrosion resistance and workability.
5tJS 630. SO3316) is used.

At this time, as shown in Table 1, the thermal expansion coefficient of the cap body 2 is larger than that of the nozzle piece I, so stress is applied to the nozzle piece L during cooling after brazing during the manufacturing process of the preventive cap. By keeping the brazed portion short, no cracks will occur in the nozzle piece 1.

[Margin below]

Table 2 Also, as shown in the enlarged cross-sectional view in Fig. 2, the brazing material 3 is
It is filled between the nozzle piece 1 and the mouthpiece body 2 over the entire circumference, and can firmly connect the nozzle piece 1 and the mouthpiece body 2 and completely seal the joint.

Furthermore, in the bonding structure shown in FIG. 1, only the tip of the stepped portion 1c is brazed, the rear end is not bonded, and the temperature is zero at room temperature.
Or, it is a state in which a minute gap occurs. Therefore,
Even if there is a dimensional difference in the longitudinal direction of the nozzle piece 1 due to the difference in thermal expansion between the nozzle piece 1 and the mouthpiece body 2, it is possible to prevent the distal end surface of the nozzle piece 1 and the lower surface of the mouthpiece body 2 from misaligning.

Next, a method of connecting the nozzle piece 1 and the mouthpiece body 2 will be specifically explained.

Nozzle piece 1 has a diameter of 6 mm and a length of 20 mm.

The brazing length is 3 mm, and the base body 2 is made of stainless steel (
SUS 630) was used. Also, the brazing width d is 0,0
It was set to be 5 mm. Then, the brazing portion of the nozzle piece 1 was metal plated or metallized, and using silver solder as the brazing material 3, brazing was performed at a temperature of about 850°C.

The above joining method is the same even if the materials of the nozzle piece 1 and the mouthpiece body 2 are changed, and the brazing width d, type of brazing material 3, and brazing temperature are determined to be optimal depending on each material. Good.

Next, an experiment was conducted to find the optimum range of the brazing length t.

A spinneret having the structure shown in FIG. 1 and having 34 nozzle pieces was prototyped and tested for use. As shown in Table 2, a total of 20 spinnerets were prepared, with four spinnerets each having five different brazing lengths t.

For each, the number of nozzle pieces in which cracks occurred during manufacturing was determined. For Nα1 to Nα4, we installed four spinnerets in one spin box and melt-spun the polymer at various pressures, and measured the pressure at which even one leak occurred after 48 hours. Pressure resistant.

The results are shown in Table 2. In the case of Nα5 with a brazing length t of 10 mm, cracks occurred in the nozzle piece l during the manufacturing process and during cooling after brazing, and a use test could not be performed. On the other hand, since the brazing length t of Nαl-4 was 7 mm or less, the use test could be conducted without cracking the nozzle piece 1 because the brazing length t was short. . In addition, regarding pressure resistance, since 250Kg/cm2 or more is required in normal use, the brazing length t of Nα1 is 2 mm, so the pressure resistance is 200Kg/am2L.
It is not suitable for actual use.

For these, the brazing length t of Nα2-4 is 3-7
The example of the present invention with mm has a pressure resistance of 300 Kg/cm.
The fact that there are 2 or more indicates that there is no problem in normal use and it is excellent.

In the above experimental example, similar experiments were conducted using only cermet as the material of the nozzle piece l, or using other ceramics or cemented carbide, and the results were almost the same.

〔Effect of the invention〕

As described above, according to the present invention, the nozzle piece made of ceramics, cermet, or cemented carbide is partially and By brazing the entire circumference of this part, it is possible to obtain a spinneret with excellent sealing properties at the joint without causing cracks in the nozzle piece during manufacturing.

In addition, since the spinning hole is made of ceramics, cermet, or cemented carbide, there is less adhesion and wear of carbides in the molten raw solution, resulting in a long life.Furthermore, since the nozzle piece is attached, the manufacturing yield is high and the cost is low. We can provide a spinneret with many features at low cost.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a spinneret according to an embodiment of the present invention. FIG. 2 is a partially enlarged sectional view of the vicinity of the spinning hole in FIG. 1. FIG. 3 is a partially cutaway cross-sectional view showing a conventional spinning nozzle. Nozzle piece introduction hole 20k gold body b: Spinning hole/brazing material

Claims (2)

[Claims] (1) A nozzle piece made of ceramics, cermet, or cemented carbide was inserted into a mounting hole of a metal mouthpiece body, and brazed partially in the longitudinal direction of the nozzle piece and over the entire circumference in this part. A spinneret characterized by: (2) The spinneret according to claim 1, wherein the length of the brazed portion is 3 to 7 mm.