JPS5838523B2 - Melt spinning equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a melt-spinning apparatus, and more particularly to a melt-spinning apparatus equipped with a device for supplying water vapor to the spinneret surface to suppress fouling of the spinneret.

Generally, when a thermoplastic polymer such as polyamide is melt-spun, low-molecular compounds are volatilized and some of them adhere to the die surface and are thermally denatured, resulting in so-called die staining.

When this nozzle dirt accumulates and increases, the spun filament yarn becomes unstable, causing bending and twitching, and even yarn breakage, which has a significant negative impact on quality and productivity.

Therefore, it is common practice to periodically wipe the mouth surface with a heat-resistant mold release agent or the like.

However, since spinning had to be temporarily suspended, there were problems such as a decrease in production, an increase in waste, a decrease in quality, and an increase in labor costs, and controlling the fouling of the spinnerets was an extremely important issue.

It is known that a method of providing multiple spinneret surfaces is effective in suppressing die fouling in melt spinning, and many specific methods and devices for supplying water vapor to the spinneret surfaces have been proposed.

However, the mechanism is complicated and equipment costs are high, the supply of water vapor is not uniform and yarn unevenness tends to occur, or crystals of low-molecular-weight compounds grow around the outer periphery of the yarn path and prevent damage to the yarn. There were various drawbacks.

In other words, many methods have been proposed for supplying steam from outside to a steam supply device installed below the cap, but in each case, a precise pressure adjustment device and steam condensation prevention device are required in the steam piping system. This is extremely expensive equipment.

On the other hand, regarding a method in which water or hot water is supplied from the outside to a steam supply device provided below the mouthpiece, heat is evaporated at the cutting edge, and the generated steam is supplied to the face of the mouthpiece, for example, Japanese Patent Publication No. 483
A device such as No. 2603, which directly heats a water reservoir from the bottom or side to generate steam, has been proposed, but direct heating causes uneven evaporation, and especially at temperatures at or near the boiling point, a bumping phenomenon occurs. However, there was a drawback that stable water vapor could not be efficiently generated.

In addition, the water reservoir is necessarily provided facing the yarn passage passage section, and the crystals of the low-molecular-weight compound described above are formed on the outer wall of the water reservoir, which does not exceed 100°C, that is, the outer wall of the yarn passage section. As it accumulates, it will eventually interfere with the yarn, so
It is necessary to periodically dispose of this material, which has serious drawbacks such as an increase in labor costs.

The purpose of the present invention is to generate water vapor stably and efficiently using an extremely simple device free from the above-mentioned drawbacks, to constantly supply water vapor to the surface of the mouthpiece, and to remove the polymer from the mouth in order to suppress fouling of the mouthpiece. An object of the present invention is to provide a melt spinning device equipped with an excellent steam supply device that prevents the formation of volatilized low-molecular compound crystals around the yarn path.

The present invention has the following configuration.

That is, the present invention provides a steam supply device for supplying water vapor to the spinneret surface installed in a heating and heat-insulating cylinder to suppress staining of the spinneret surface, wherein the steam supply device is provided in contact with the lower surface of the heating and heat-insulating cylinder. This is a melt spinning device that is equipped with a steam generation chamber and a steam chamber adjacent to the steam generation chamber. In a steam supply device for suppressing dirt, the steam supply device includes a steam generation chamber provided in contact with the lower surface of the heating and insulation cylinder and a steam chamber adjacent to the steam generation chamber, and the steam supply device includes a steam generation chamber provided in contact with the lower surface of the heating and insulation cylinder, and a steam chamber adjacent to the steam generation chamber. The present invention relates to a melt spinning device with a heat source provided above the surface.

Hereinafter, the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of the melt spinning apparatus of the present invention.

1 is a heating and heat-insulating tube, 2 is a cap, 3 is a steam generation chamber, 4 is a steam chamber, 5 is a thread passage tube, 6 is a water pipe, 7 is a heat insulating material, 8 is a low molecular compound suction device, 9 is for filament cooling Cold air blowing device, 10 is a liquid level adjustment device with one overflow type,
11 is a melting upper cooling drain pipe, and 13 is a spun filament.

In FIG. 1, water enters the liquid level preparation device 10 from the melting upper cooling drain pipe 11, and passes through the water pipe 6 to the steam generation chamber 3.
is replenished so that the liquid level remains constant.

The water stored in the steam generation chamber 3 is indirectly heated from the liquid surface by heat transfer from the heating and insulation cylinder 1, which is a heat source installed above the steam generation chamber, and is prevented from causing bumping near the liquid surface. (It boils gently and generates steam.

The steam generated in the steam generation chamber 3 enters the adjacent steam chamber 4, where it evaporates the entrained droplets and becomes complete steam.

Next, the steam passes through the gap between the yarn passing cylinder 5 and the heating and heat-insulating cylinder 1, and is supplied to the nozzle surface, and the surface of the nozzle 2 is continuously exposed. It descends inside the passage tube 5 and is discharged from the low molecular compound suction device 8.

The steam supply rate can be adjusted arbitrarily by adjusting the heat receiving area of the heat transfer amount of the steam generation chamber 3, but 0.5 to 5 t/min is appropriate when considering the effect of suppressing the nozzle contamination and the quality of the obtained product. .

In the device of the present invention, since the outer wall of the yarn passing cylinder 5 is not in contact with water, the temperature is constantly maintained at 100° C. or higher by heat transfer from the heating and heat-insulating cylinder 1.

As a result, the formation of crystals of low-molecular-weight compounds is almost suppressed, and even disappears at temperatures above 125°C.

FIG. 2 shows another embodiment of the invention.

A power solar heater 1 is installed in the upper part of the steam generation chamber 3 and the steam chamber 4.
2 is provided, and is effective when sufficient heat transfer from the heating and heat-insulating cylinder 1 cannot be obtained.

As described above, the device of the present invention introduces water into the steam generation chamber 3 provided in contact with the lower part of the heating and heat-insulating cylinder 1, and at least the water does not bump up due to the heating from the upper heat source, and the water near the water surface remains calm. It continuously boils and evaporates into water vapor, and the adjoining steam chamber prevents entrainment, so when this device is used, uniform water vapor is stably and sufficiently supplied to the mouth surface, thereby eliminating thread spots. The amount of dirt on the mouthpiece surface can be significantly suppressed, and the attachment of low-molecular-weight compounds to the yarn passing cylinder is eliminated.

In the present invention, the height from the bottom of the steam generation chamber to the inner wall ceiling is 10 to 307 nrrL, and the height of the space above the water surface (from the liquid level to the ceiling of the steam generation chamber) is 2 to 25 mm.
It is preferable to set it as approximately.

That is, if the space above the water surface is less than 2 mm, water comes into contact with the soil wall due to liquid level fluctuations due to boiling, causing intense evaporation, making the amount of water vapor generated unstable, and increasing thread spotting.

On the other hand, if it exceeds 25 mm, the heating efficiency by the upper heat source will decrease.

Also, the height from the bottom of the steam generation room to the ceiling of the inner wall is 1
If it is less than 07n7IL, it is difficult to secure sufficient water depth and space above the water surface to continuously generate stable water vapor, and if it exceeds 30mm, workability such as applying silicone to the mouthpiece surface will be significantly deteriorated.

Furthermore, the water used for cooling in the melt spinning section is used as the water introduced to the steam generator.

This is hot water (30 to 90°C), which is preferable because it saves energy.

In the embodiments of the present invention, an overflow type is adopted as a device for adjusting the water surface height in the steam generation chamber, but the present invention is not limited to this embodiment, and other means such as a metering pump or a flow rate control device are used. You may use a device that uses a meter to supply water in proportion to the amount of evaporation, or a device that electrically detects the liquid level and automatically replenishes water, but the overflow type is simple in terms of equipment. preferable.

Furthermore, the present invention is such that the yarn passing tube 5 and the steam chamber 401 are detachable and replaceable, so that regular mouthpiece replacement and silicone coating on the mouthpiece surface 1 can be carried out without moving the steam generating chamber. Work can be carried out safely and efficiently.

It goes without saying that if the whole or part of the side and/or bottom surfaces of the steam generation chamber and the steam chamber are surrounded with a heat insulating material, the heat retention effect will be good.

As described above, in the present invention, the effect of suppressing dirt on the mouth surface is remarkable, there is no quality defect such as thread spotting, and there is no problem with the thread passage due to the formation of low molecular weight compounds, so stable production is possible for a long period of time. The structure is extremely simple, the equipment cost is low, and it is easy to handle.

[Brief explanation of the drawing]

FIGS. 1 and 2 are schematic sectional views showing different embodiments of the melt spinning apparatus according to the present invention. 1: heating and insulation tube, 2: base, 3: steam generation chamber, 4: steam chamber, 5: yarn passing tube, 7: heat insulating material, 10: liquid level adjustment device, 12: heater.

Claims (1)

[Scope of Claims] 1. A melt-spinning apparatus equipped with a steam supply device that supplies water vapor to a spinneret surface installed in a heating and heat-insulating tube to suppress staining of the spinneret surface, wherein the steam supply device includes a heating and heat-insulating tube. A steam generation chamber provided in contact with the lower surface, a steam chamber provided adjacent to the steam generation chamber, a yarn passage tube provided through the steam chamber, and above the liquid level of the steam generation chamber. 1. A melt spinning apparatus comprising: a heating device which boils and evaporates water supplied into the steam generating chamber in a non-bumping manner. 2. The melt-spinning apparatus according to claim 1, wherein the power U heat device is a ceiling plate of a steam generation chamber heated by heat transfer from a heating and heat-insulating cylinder. 3. The melt spinning apparatus according to claim 1, wherein the heating device is a heater provided on the lower surface of the heat insulation cylinder. 4 The height from the floor to the ceiling of the steam generation room is 10 to 3
2. The melt spinning apparatus according to claim 1, wherein the steam generating chamber is arranged such that the height from the liquid level to the ceiling of the steam generating chamber can be adjusted to 2 to 25 mm. 5. The melt spinning apparatus according to claim 1, which is provided with a device for adjusting the liquid level height in the steam generation chamber.