JPS6039404A - Correction of face of spinneret in melt spinning - Google Patents

Abstract

PURPOSE:To correct face of a large number of spinnerets of spinning device, by using an automatic device for correcting faces of spinnerets capable of freely moving and stopping on a transfer rail set along the spinning device ahead a spinning unit. CONSTITUTION:The robot 7 is moved on a transfer rail set ahead a spinning unit, stopped at the front of a spinneret, the working arms 9 and 10 are operated, the switch 13 is pushed to suspend the feed of a polymer. The working arms 9 and 10 are set at the lower part of the center of the face of the spinneret, the working arm 10 is moved upward, the correction attachment 11 is brought into contact with the face of the spinneret and rotated. After the correction is over, the arm 10 is dropped, the switch 13 is pushed to restart the feed of the polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for modifying a spinneret surface in melt spinning, and an object thereof is to mechanically modify the spinneret surface of a spinning device having a large number of spinnerets. The goal is to provide a way to do so.

Ill! is used on the discharge surface of spinnerets used for melt spinning thermoplastic polymers such as polyester and polyamide. I! The release agent is sprayed or applied, but if melt spinning continues for a long time at high temperatures, the release agent may thermally decompose or
Furthermore, it is chemically decomposed by decomposable gases such as aldehydes generated during spinning, and its releasability is rapidly lost. As a result, oligomers, catalyst residues, and additives such as titanium dioxide become foreign substances that adhere to the surroundings of the spinning holes drilled in the spinneret, and grow over time, and in extreme cases, 1/1/2 of the spinning holes are deposited. There are even cases where the number 10 is overtaken.

If such foreign matter adheres to the area around the spinning hole, the stable discharge of the polymer will be hindered, including the spinning process.

Yarn breakage begins to occur frequently during processes such as drawing.

Therefore, it is necessary to occasionally modify the spinneret surface (brushing, treatment with a release agent, etc.) to keep it clean. Several proposals have been made regarding methods for modifying the spinneret surface (for example, Japanese Patent Publications Nos. 42-25481 and 47-17).
No. 726) was made by hand.

There were problems both in terms of cost and the success rate of repairs.

In particular, in recent years, in order to modernize equipment and improve productivity per unit space, the so-called multi-filament spinning method has been widely adopted, and the labor required to modify the spinneret surface is
This is becoming a cost factor that cannot be ignored.

In addition, the area directly under the spinneret is at a high temperature and the decomposable gases mentioned above remain there, and the work environment is extremely poor as mold release agent is sprayed when modifying the spinneret surface. Improvement is strongly requested.

The present invention provides a spinneret surface correction method that solves these problems by using an automatic spinneret surface correction device, and the gist thereof is as follows.

An automatic spinneret surface correction device that can freely move and stop on a moving rail provided along the spinning device in front of the spinning unit when correcting the spinneret surface in a melt spinning device in which many spinning units are lined up in a row. 1. A method for modifying a spinneret surface in melt spinning, the method comprising modifying a spinneret surface in a first step using a method.

(11) Stop the automatic spinneret surface correction device in front of the spinning unit with the spinneret to be corrected.

(2) Turn off the drive switch of the polymer discharge metering pump.
Make it F.

(3) Correct the spinneret surface.

(4) Turn on the drive switch of the polymer discharge metering pump.
Make it.

The spinning device to which the method of the present invention is applied is as follows.

A spinning unit that has a spinneret device for spinning the polymer, a cooling device for cooling the spun polymer, and a chimney for transferring the spun yarn to a winding chamber are arranged in one row. However, as a cooling device, a horizontal cooling device that sprays air at right angles from one side of the spun yarn generally has a larger space directly under the spinneret device, so it is not suitable for automatic spinnerets, which will be described later. A surface correction device (hereinafter simply referred to as a robot) is preferable because it is easy to work with.

In the present invention, the moving rail on which the robot moves must be provided in front of the spinning unit and along the spinning device. The provision of the moving rail in this manner allows the smooth operation of said robot by simply stopping the supply of polymer only in the spinning unit with the spinneret to be corrected without stopping the polymer discharge of the entire spinning apparatus. This makes it possible to move around.

In the present invention, the modification of the spinneret surface by the robot is
Specifically, the process is as follows.

In other words, when you input the number of the spinneret whose spinneret surface you want to correct into the robot, the robot automatically moves to the front of the spinning unit that has that spinneret and immediately turns off the drive switch of the polymer discharge needle pump. ,
The supply of polymer to that spinning unit is stopped.

Note that the spinning unit here is distinguished for each of the metering pumps for discharging the polymer, and one spinning unit usually includes 1 to 4 spinnerets. There is no problem if the number of spinning units and spinnerets is the same, that is, if each spinneret device is provided with a metering pump for discharging the polymer, but if the number of spinning units is 211
Considering the case where M or more spinneret devices are involved.

It is preferable to provide a switch for turning ON/OFF the drive of the metering pump for discharging the polymer for each spinneret device.

In this way, after a while (approximately 10 seconds) after the polymer discharge metering pump has stopped driving, the robot's working arm operates when the spun yarn disappears and corrects the predetermined spinneret surface. . In this case, the working arm of the robot needs to have a telescoping mechanism and a rotation mechanism. Attach an axotiment for correction to the tip of the working arm in advance.

Further, it is preferable to spray a fresh mold release agent onto the spinneret surface before and after the modification, and especially after the modification, and it is preferable to provide a mold release agent spraying device to the two working arms.

After correcting the spinneret surface in the above procedure, turn on the drive switch of the polymer discharge needle pump, move to another spinneret that requires correction, if necessary, and repeat the same operation.

As described above, in the present invention, since the correction of the spinneret surface is completely automated, it is particularly effective when a large number of spinnerets are periodically corrected all at once.

The method of the present invention will be explained in more detail below with reference to the drawings.

FIG. 1 is a schematic plan view of a spinning apparatus to which the method of the present invention is applied, and FIG. 2 is an operational view showing an example of a spinneret surface correction operation performed by a robot used in the method of the present invention.

Polymer discharge metering pump 2 attached to spinning head 1
The measured molten polymer is spun by a spinneret device 4 equipped with a spinneret 3. The spun yarn (not shown) is cooled by the cooling air blown from the main duct and blown at right angles by the cooling device 5, and is cooled by the chimney.
6 to the winding room. FIG. 1 shows an example in which four spinneret devices are installed in one spinning unit.

In front of each spinneret device is a switch 13 for turning on and off the drive device 12 of the polymer discharge needle pump.
is attached. The robot 7 can freely move and stop on a moving rail 8 provided in front of the spinning unit.

Further, working arms 9 and 10 are connected to the robot, and a correction actuator 1 (a brush in FIG. 2) is attached to the tip of the working arm 10.

In addition to this, the robot body also has programs for moving the robot itself to the front of the spinneret to be corrected, 5 for controlling the working arm to a position and posture that makes it easy to make corrections, and 2 timers and programs for regulating various operating times. is built-in.

For example, when the number of the spinneret to be modified is input into the robot nod, the robot automatically moves to the front of the spinneret, activates the working arm 9 and 10, and activates the switch 13.
Press to stop the polymer supply. After about 10 seconds, the working arms 9 and 10 are now centered below the center of the spinneret surface, and then the working arm 10 is moved upward.

When the correction attachment 11 comes into contact with the spinneret surface and reaches a certain height, the upward movement stops and it immediately begins to rotate. Then, the arm 10 is rotated for a certain period of time (about 5 seconds is sufficient), and when the correction is completed, the arm 10 is lowered and returned to the predetermined position, and the switch 13 is pressed again to resume supplying the polymer.

Thus, by employing the method of the present invention, it is possible to automate the modification of a large number of spinneret surfaces, improve the success rate, and significantly reduce costs.

EXAMPLES Hereinafter, the effects of the present invention will be specifically explained with reference to Examples.

Example 1 Polyethylene terephthalate having an intrinsic viscosity [η] of 0.68 was spun at a temperature of 290° C. and at a spinning speed using a spinning device having a 96-spinneret with a methylphenyl silicone release agent applied to the spinneret surface. When melt spinning was carried out at a discharge rate of 1,400 mm/min and the denier composition of the final product (drawn yarn) was 75 deniers/36 filaments, the yarn breakage rate during drawing exceeded 2% in about 7 days, so the total spinning The cap was modified using a robot as shown in Figure 2. The correction time using the rotating brush was set to 5 seconds. A mold release agent spraying device was attached to the working arm 10 of the robot, and the mold release agent was sprayed after correction using a single rotation brush.

The time required to fix all 96 spinnerets was approximately 40 minutes. After the correction was completed, spinning was restarted.
The thread breakage rate during stretching was drastically reduced to 0.2%.

The number of spinnerets that had to be corrected again due to poor correction was only two.

On the other hand, the time required for three workers to repair all 96 spindles without using a robot was also approximately 40 minutes, but there were 10 defective spindles that required re-correction. The yarn breakage rate during stretching was also reduced to only 0.8%.

Note that the yarn breakage rate during drawing herein is defined by the following formula, and serves as a measure of operability during drawing.

Yarn breakage rate (%) - In the above formula, yarn breakage pirns include not only burns in which the yarn is completely broken and becomes thin, but also burns in which the yarn is completely broken but a single yarn is broken during drawing. on the other hand.

A fully stirred pirn means one in which there is no complete cutting or single yarn cutting.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view of a spinning apparatus to which the method of the present invention is applied, and FIG. 2 is an operational view showing an example of a spinneret surface correction operation performed by a robot used in the method of the present invention. 2... Needle volume pump for discharging polymer, 3... Spinneret. 8...Movement rail, 9.10...Working arm,
11... Correction attachment, 12... Needle amount pump drive device. 13... Needle amount pump drive switch. Patent applicant Nippon Ester Co., Ltd. Unitika Co., Ltd.

Claims (1)

[Claims] (1) An automatic spinneret that can be freely moved and stopped on a moving rail provided along the spinning device in front of the spinning unit when modifying the spinneret surface in a melt spinning device where many spinning units are lined up in one row. 1. A method for modifying a spinneret surface in melt spinning, the method comprising modifying the spinneret surface in a first step using a surface modifying device. (a) Stop the automatic spinneret surface correction device in front of the spinning unit that has the spinneret to be corrected. (b) Turn off the drive switch of the polymer discharge metering pump.
Make it F. (Correct the C1 spinneret surface. (d) Turn on the drive switch of the polymer discharge needle pump.
Make it.