JPS59112063A - Heat treatment apparatus for preparing flame resistant yarn - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a heat treatment apparatus for producing flame-resistant yarn.

Today, carbon fiber is attracting attention as a base material for forming composite materials by integrating it with a matrix made of resin or metal, and it can be said that such composite materials have reached the stage of practical use. The mainstream is to use acrylonitrile fibers or what is commonly called pitch fibers as raw materials, and these raw material fibers are subjected to flame-retardant treatment or oxidation treatment before being carbonized. It is customary to oxidize raw material fibers in a heated oxidizing atmosphere.

Now, in this flame-retardant treatment or oxidation treatment (hereinafter simply referred to as flame-retardant treatment), rollers are placed above and below the heat treatment area as a device for continuously heat-treating the multifilar fibers. A device (so-called "vertical outside roll type heat treatment furnace") that continuously heat-treats the fibers by providing slits in the upper and lower parts of the heat treatment chamber through which the fibers pass is generally used.

In addition, in this heat treatment apparatus, since there is heated gas (usually air heated to 20.0 to 400°C, hereinafter simply referred to as heated air) in the heat treatment chamber, the chimney effect due to the temperature difference between the outside and outside of the heat treatment chamber causes It is also known that there is a phenomenon in which hot air blows out through the upper slit and cold air is sucked through the lower slit.

To deal with this phenomenon, according to Japanese Patent Publication No. 54-1815, seal chambers having slits for fiber passage are provided at the upper and lower portions of the heat treatment chamber, and gas is supplied to this upper seal chamber.
On the other hand, by sucking in cold air (outside air) in the lower seal chamber,
A method of sealing a heat treatment chamber has been proposed to prevent the leakage of heated air in the heat treatment chamber and the intrusion of outside air into the heat treatment chamber. However, it can be prevented to some extent.

However, as today's flame-retardant treatment equipment becomes larger and the fibers to be treated become more multi-filared, simply providing seal chambers above and below the heat treatment chamber will not allow the fibers to become a kind of barrier. This has the disadvantage that the seal balance in the seal chamber is likely to collapse. If this seal balance is disrupted, heated air inside the heat treatment chamber may leak or outside air may enter the heat treatment chamber, resulting in variations in physical properties between yarns due to temperature unevenness within the heat treatment chamber, deterioration of the working environment, and the heated air entering the heat treatment chamber. This causes heat loss due to leakage. Furthermore, if the heated air in the heat treatment chamber leaks, because the heated air contains tar-like substances, the sealed chamber where the heated air and gas (or outside air) of a relatively lower temperature are combined, Tar-like substances condense near the medium gas outlet or outside air suction section, and this not only adheres to the yarn and causes yarn damage and fuzz, but also damages the yarn in the heat treatment chamber. This causes running abnormalities (e.g., thread wrapping around rollers, thread breakage, etc.).

Therefore, in the heat treatment chamber sealing method described above,
How to easily and as much as possible reduce leakage of heated gas and intrusion of outside air has been considered an important technical issue in the process of flame-retardant treatment of fibers.

In contrast, the present inventors have developed a vertical outside-furnace roll type heat treatment apparatus for flame-retardant treatment of fibers. In addition to providing a heated gas exhaust duct +, the lower part of the heat treatment chamber is designed to draw in and draw outside air from the bottom to the top.
It was proposed that a sealed chamber for exhaust and a supply duct for heated gas could be installed to prevent leakage of heated air inside the heat treatment chamber and intrusion of outside air into the heat treatment chamber. However, in order to prevent quality or process abnormalities caused by the above-mentioned tar-like substances in the event of leakage, the present invention was developed as a result of intensive studies.

That is, the configuration of the present invention is as follows.

In a heat treatment chamber in which the fibers are continuously transferred in a heated gas through a group of rollers provided at the upper and lower parts of the heat treatment chamber, and during this time the fibers are oxidized, at the upper and lower parts of the heat treatment chamber, a heated gas discharge section and a supply section;
Above the heated gas discharge section and below the heated gas supply section, sealing chambers as many as the number of spaces are provided in the spaces defined by the fibers being transferred, and the sealing chambers are equipped with heating means. A heat treatment apparatus for producing flame-resistant yarn, characterized in that among the seal chambers, a gas different from the heating gas is supplied to the upper seal chamber, while outside air is sucked and discharged from the lower seal chamber. .

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

FIG. 1 is a schematic cross-sectional view showing an embodiment of the heat treatment apparatus for producing flame-resistant yarn according to the present invention, FIG. 2 is a side cross-sectional view seen from the right side of FIG. 1, and FIG. FIG.

In FIGS. 1 and 2, the fiber 1 is attached to the outer upper and lower guide rollers 3a of the heat treatment chamber 2.

3b, 4a, 4b, and 4c, the fiber 1 is continuously transferred into a heat treatment chamber under heated air, and during this time, the flameproofing treatment of the fiber 1 is performed.

In this heat treatment chamber 2, in the upper and lower parts of the space defined by the fibers 1 being transferred, there are discharge parts 5a, 6b, 6c for heating gas as many as the number of spaces.

6, d, 6e and supply parts 5a, 5b, 5c.

5d, 5e, and a sealing chamber 8a that supplies a gas different from the heated gas (usually air at a lower temperature than the heated gas, hereinafter simply referred to as air) above the heated gas discharge parts 6a to 6e; 8. b.

8, C, 8e, and a sealing chamber 7a that sucks and discharges air outside the heat treatment chamber below the heating gas supply parts 58 to 5e;
7b, 7c, 7cJ, and 7e are provided.

These seal chambers 8a to 8e' and 7a to 7e are respectively engaged with air supply passages and suction/exhaust passages (not shown) in which air volume adjusting means (usually dampers) are interposed.

As shown in FIG. 3, the sealing chamber is equipped with a perforated plate 9 on one side facing outside of the heat treatment chamber for blowing out air or sucking outside air, and a heating means is provided inside the sealing chamber. It is equipped with 1o.

This perforated plate is usually a rectifying wire mesh, punched metal, etc., but in particular, the perforated plate has a hole diameter of 3 to 8 TrL/TrL1.
Punched metal with a porosity of 10 to 35% is preferably used.

Also, as a heating means, an electric heater is mainly used.

In the above-mentioned heat treatment chamber 2, heated air of usually 200 to 400°C is circulated through its supply parts 5a to 5e and discharge parts 6a to 6e. Due to the difference, hot air blows out from the upper fiber passage, while outside air is sucked into the lower fiber passage and inevitably enters the heat treatment chamber 2.

Against the hot air blown out from the upper passage of this fiber,
Air is blown out from the perforated plate 9 of the seals v8a to 8e,
On the other hand, for the outside air sucked from the lower passage of the fibers,
Outside air is sucked in and exhausted through the perforated plates 9 of the seal chambers 7a to 7e, and this sufficiently prevents hot air from blowing out from the heat treatment chamber 2 or from drawing outside air into the heat treatment chamber 2.

Here, the first structural feature of the heat treatment apparatus is that the seal chambers 8a to 8e and 7a to 7e are arranged in the heat treatment chamber 2 in the number of spaces partitioned by the fibers to be transferred. That's true.

As a result, in the upper seal chambers 8a to 8e, the air volume balance between the air blown from each seal chamber and the hot air blown from the upper fiber passage can be easily adjusted without being disturbed by the fibers being transferred. In the chambers 7a to 7e, the balance between the suction of outside air in each sealing chamber and the action of the heat treatment chamber 2 to suck outside air from the lower passage of the fibers can be easily adjusted, as in the case of the upper sealing chamber. be.

Next, the second feature is that the sealing chamber is provided with heating means 10. That is, the seal chambers 7a to 7 described above
Even if the heat treatment chamber 2 is equipped with
During flame-retardant treatment of fibers, in order to prevent air or outside air from entering the heat treatment chamber, it is necessary to set a seal balance that allows some heated air to leak out. The air blown out from the sealing chamber or the outside air sucked into the lower sealing chamber cools and condenses (usually occurs at temperatures below 200°C), which may adhere to the fibers and cause process or quality abnormalities.

For this reason, the sealing chamber, especially the vicinity of the air blowing part and the outside air suction part, is heated to about 200° C. or higher to prevent the tar-like substances in the heated air from condensing.

This makes it possible to sufficiently prevent process or quality abnormalities due to rel-like substances during flame-retardant treatment of fibers.

In addition, even with such means, if tar-like substances condense and adhere to the perforated plate 9 constituting the air blowing part and the outside air suction part, the perforated plate 9 may be removed as necessary even during the flameproofing process. It is desirable that the perforated plate 9 has a removable structure so that it can be replaced.

As described above, the heat treatment apparatus for producing flame-resistant fibers of the present invention has the upper and lower parts of the heat treatment chamber divided by the m fibers transferred through the heat treatment chamber, each having the same number of spaces as the number of spaces. By arranging seal chambers, among these seal chambers, air is blown out in the upper seal chamber, while outside air is sucked in and exhausted from the front seal chamber, and a heating means is provided inside the seal. This solves the problem that conventional sealing methods for heat treatment and processing equipment for flame-resistant yarn production cannot sufficiently prevent the leakage of heated air inside the heat treatment chamber and the intrusion of outside air into the heat treatment chamber. Even when using this method, it is possible to prevent process abnormalities such as fiber wrapping around rollers and gold thread breakage due to tar-like substances in the heated air, as well as quality abnormalities that deteriorate the physical properties of the fibers, and also improve the working environment. During the process of flame-retardant treatment of fibers called colander,
It has excellent effects.

[Brief explanation of drawings]

Fig. 1 is a schematic sectional view showing an embodiment of the heat treatment apparatus for producing flame-resistant yarn according to the present invention, Fig. 2 is a side sectional view seen from the right side of Fig. 1, and Fig. 3 is a heating method according to the present invention. It is a sketch of the main part of the sealing chamber equipped with the means. 1: Fiber 2: Heat treatment chambers 3a, 3b, 4a, 4b, 4c: Guide rollers 5a, 5b, 5c, 5d, 5e: Heated air supply section 6a, 6b, 5c, 5e: Heated air discharge section 7a,
7'b, 7c, 7d, 7e: Lower seal chamber 8a, 8b, 8c, 8d, 8e: Upper seal chamber 9: Perforated plate 10: Heating means (heater) Patent applicant Toshi Co., Ltd. Figure 1 Figure 2 Figure 3

Claims (4)

[Claims] (1) Continuously transporting the fibers in a heated gas through a group of rollers provided at the upper and lower parts outside the heat treatment chamber,
During this time, in the heat treatment chamber in which the fibers are oxidized, a heated gas discharge part and a supply part are provided in the upper and lower parts of the heat treatment chamber, and above the heated gas discharge part and below the heated gas supply part, and a In the space divided by the fibers inside,
As many sealing chambers as there are spaces are provided, and each of the sealing chambers is equipped with a heating means, and a gas different from the heating gas is supplied to the upper sealing chamber, while outside air is supplied to the lower sealing chamber. A heat treatment device for producing flame-resistant yarn characterized by suction and discharge. (2) The heat treatment apparatus for producing flame-resistant yarn according to claim (1), wherein the sealing chamber has a gas blowing part or an outside air suction part made of a perforated plate. (3) Claim No. (2) in which the perforated plate is removable.
A heat treatment apparatus for producing flame-resistant yarn as described in 1. (4) The heat treatment apparatus for producing flame-resistant yarn according to claim (2), wherein the perforated plate has an opening degree in the range of 10 to 35%.