JPH034834B2 - - Google Patents
Info
- Publication number
- JPH034834B2 JPH034834B2 JP7335486A JP7335486A JPH034834B2 JP H034834 B2 JPH034834 B2 JP H034834B2 JP 7335486 A JP7335486 A JP 7335486A JP 7335486 A JP7335486 A JP 7335486A JP H034834 B2 JPH034834 B2 JP H034834B2
- Authority
- JP
- Japan
- Prior art keywords
- heat treatment
- treatment chamber
- hot air
- yarn
- chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000010438 heat treatment Methods 0.000 claims description 49
- 238000005192 partition Methods 0.000 claims description 18
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 10
- 239000004917 carbon fiber Substances 0.000 claims description 10
- 238000007789 sealing Methods 0.000 claims description 7
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 3
- 238000007664 blowing Methods 0.000 claims description 2
- 238000000034 method Methods 0.000 description 8
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 5
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000000835 fiber Substances 0.000 description 3
- 239000003063 flame retardant Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 229920002994 synthetic fiber Polymers 0.000 description 3
- 239000012209 synthetic fiber Substances 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000003763 carbonization Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 230000002250 progressing effect Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
Landscapes
- Treatment Of Fiber Materials (AREA)
- Tunnel Furnaces (AREA)
- Inorganic Fibers (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は高性能炭素繊維を高速生産性下に製造
するのに適した熱処理炉、とくに耐炎化熱処理炉
に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a heat treatment furnace suitable for producing high-performance carbon fibers at high speed productivity, and particularly to a flame-retardant heat treatment furnace.
炭素繊維、とくにアクリロニトリル系合成繊維
を原料として作られた炭素繊維は、その引張強度
が500Kg／mm2以上、伸度２％以上と極めて高性能
なものとすることができるため、航空、宇宙用素
材としての用途開発が進められている。
Carbon fibers, especially carbon fibers made from acrylonitrile synthetic fibers, have extremely high tensile strength of 500 kg/mm 2 or more and elongation of 2% or more, making them suitable for aerospace and aerospace applications. Development of applications as a material is progressing.
アクリロニトリル系合成繊維を出発原料として
炭素繊維を製造するには、まず該繊維を200〜350
℃の酸化性雰囲気下で耐炎化処理することが必要
であるが、この耐炎化反応工程は発熱反応である
ため、一挙に大量の糸条を耐炎化処理すると、耐
炎化反応の暴走が起こり、着火現象が認められる
に至るため、これまでは、できるだけ糸間隔を設
けた小規模焼成法により作らざるを得ず、その製
造コストの低減は極めて困難なものとなつてお
り、従来より、この困難を解決するための方法が
提案されてきた。 To produce carbon fiber using acrylonitrile synthetic fiber as a starting material, first the fiber is
It is necessary to carry out flameproofing treatment in an oxidizing atmosphere at ℃, but since this flameproofing reaction process is an exothermic reaction, if a large amount of yarn is flameproofed at once, the flameproofing reaction will run out of control. Since the ignition phenomenon has been observed, up until now, it has been necessary to use a small-scale firing method in which the threads are spaced as much as possible, making it extremely difficult to reduce manufacturing costs. Methods have been proposed to solve this problem.
例えば特公昭52−21090号公報に示される方法、
或いは特開昭55−1322号公報及び特開昭55−
71818号公報に示される方法であり、後者には熱
処理炉内に複数本上下に並べられた広巾ローラ群
の間に、アクリロニトリル系繊維束をかけ渡し、
これらローラ群を定速で熱処理炉入口より出口に
向けて移動せしめながら熱風を炉の天井部より吹
出し床部で吸気する、いわゆるホツトフル−型熱
処理炉を用いた竪型耐炎化処理炉が示されてい
る。 For example, the method shown in Japanese Patent Publication No. 52-21090,
Or JP-A-55-1322 and JP-A-55-
This is the method shown in Publication No. 71818, and the latter involves passing an acrylonitrile fiber bundle between a group of wide rollers arranged vertically in a heat treatment furnace.
A vertical flame-retardant treatment furnace using a so-called hot full type heat treatment furnace is shown, in which a group of rollers is moved at a constant speed from the inlet to the outlet of the heat treatment furnace, and hot air is blown out from the ceiling of the furnace and sucked in at the floor. ing.
これらの方法によると、連続して大量のアクリ
ロニトリル系繊維束を耐炎化処理することが可能
であるが、これら堅型炉の最大の難点は、炉内で
極部的な上昇気流が生じ、均一な温度分布を有す
る熱処理炉とすることができない点にあり、この
方法によつて得た部分的に不均一熱処理を受けた
耐炎化糸は、その炭素化処理法を工夫しても引張
強度500Kg／mm2以上の高強度炭素繊維或いは弾性
率27〜33t／mm2、引張強度500Kg／mm2以上の高強度
中弾性炭素繊維を効率よく作ることは極めて難し
い現状にある。
According to these methods, it is possible to continuously flame-retardize a large amount of acrylonitrile fiber bundles, but the biggest drawback of these vertical furnaces is that local updrafts occur within the furnace, making it difficult to maintain uniformity. However, it is not possible to use a heat treatment furnace with a uniform temperature distribution, and the flame-retardant yarn obtained by this method and partially subjected to non-uniform heat treatment has a tensile strength of 500 kg even if the carbonization treatment method is devised. The present situation is that it is extremely difficult to efficiently produce high-strength carbon fibers with an elastic modulus of 27 to 33 t/mm 2 and a tensile strength of 500 Kg/mm 2 or higher.
一方、特公昭52−21604号公報に示される如き
横型熱処理炉は、熱風の風向きを上下方向或いは
左右方向に変更して熱処理を行つてもやはり炉内
での対流現象を極めて小さくすることはできず、
均一な熱処理を行うことはできない。更に、この
横型炉ではシート状に並列した多数本のアクリロ
ニトリル系合成繊維を焼成しようとする際には熱
風の供給方法が極めて難しいという難点をも有し
ている。 On the other hand, in the horizontal heat treatment furnace as shown in Japanese Patent Publication No. 52-21604, even if heat treatment is performed by changing the direction of the hot air to the vertical or horizontal direction, the convection phenomenon inside the furnace cannot be minimized. figure,
Uniform heat treatment cannot be performed. Furthermore, this horizontal furnace has the disadvantage that it is extremely difficult to supply hot air when attempting to sinter a large number of acrylonitrile synthetic fibers arranged in a sheet-like manner.
そこで本発明者らは、熱風吹き出し口と吸気口
を糸条の通路の上下に備えた構造とするととも
に、この熱処理室の前後に糸条通過口がスリツト
状構造のシール室を設けることによつて、従来法
に比べ、極めて均一な温度制御性を備えた熱処理
炉となし得ることを見出し本発明を完成した。
Therefore, the present inventors created a structure in which a hot air outlet and an inlet are provided above and below the yarn passage, and also provided a seal chamber with a slit-shaped yarn passage opening before and after this heat treatment chamber. Therefore, the present invention was completed by discovering that a heat treatment furnace with extremely uniform temperature control compared to conventional methods can be achieved.
即ち本発明の要旨とするところは、熱処理室内
に糸条の移送方向と平行な方向へ熱風を吹き出す
熱風吹き出し口１と該熱風を熱処理室外に排出す
る為の吸気口２とを糸条の通路の上下に備え、か
つ、糸条の通路間を区画するように熱処理室内に
仕切板３を設けた熱処理室と、熱処理室の出入口
部にスリツト６を有するシール室４，５を設け、
該シール室内の糸条の通路を区画するようにシー
ル室内に仕切板７，８を設けたことを特徴とする
炭素繊維製造用の横型熱処理炉にある。 That is, the gist of the present invention is that a hot air outlet 1 for blowing hot air into the heat treatment chamber in a direction parallel to the direction of yarn transfer and an air intake port 2 for discharging the hot air to the outside of the heat treatment chamber are connected to a yarn path. A heat treatment chamber is provided above and below, and a partition plate 3 is provided in the heat treatment chamber to partition the passage of the yarn, and seal chambers 4 and 5 having slits 6 at the entrance and exit of the heat treatment chamber are provided.
This horizontal heat treatment furnace for producing carbon fibers is characterized in that partition plates 7 and 8 are provided in the sealing chamber so as to partition the passage of the yarn in the sealing chamber.
以下図面により本発明を具体的に説明する。 The present invention will be specifically explained below with reference to the drawings.
第１図は糸条Ａの移送方向と平行な方向へ熱風
を吹き出す熱風吹き出し口１ａ，１ｂ，１ｃ…
と、該熱風を熱処理室外に排出する為の吸気口２
ａ，２ｂ，２ｃ…とを糸条の通路の上下に備え、
かつ、糸条の通路を区画するように熱処理室内に
仕切板３ａ，３ｂ…を設けるとともに、熱処理室
の出入口にスリツトを有するシール室４及び５を
設け、該シール室内を糸条の通路を区画するよう
に仕切板７ａ，７ｂ…及び８ａ，８ｂ…を設けた
本発明の炭素繊維製造用の横型熱処理炉を示す。 Figure 1 shows hot air outlets 1a, 1b, 1c, etc. that blow out hot air in a direction parallel to the direction in which yarn A is transported.
and an intake port 2 for discharging the hot air to the outside of the heat treatment room.
a, 2b, 2c... are provided above and below the thread passage,
In addition, partition plates 3a, 3b, etc. are provided in the heat treatment chamber to partition the passage of the yarn, and seal chambers 4 and 5 having slits are provided at the entrance and exit of the heat treatment chamber to partition the passage of the yarn within the seal chamber. This figure shows a horizontal heat treatment furnace for producing carbon fibers according to the present invention, which is provided with partition plates 7a, 7b, . . . and 8a, 8b, .
第２図に示すように熱風吹き出し口１ａ，１
ｂ，１ｃ…より熱処理室に供給される熱風は、通
常、熱処理室外に設けた熱風加熱器１３とフアン
１４を、吸気口２ａ，２ｂ，２ｃ…と熱風吹き出
し口１ａ，１ｂ，１ｃ…とダクトにより接続して
循環使用される。シール室４及び５の前後には糸
条が通過できるようにスリツト６ａ，６ｂ，６ｃ
…が設けられている。このスリツトの開口寸法は
糸条と接触しない範囲で可能な限り狭い方が好ま
しく、この点から上下方向に調節可能なスリツト
とするのが好ましい。 As shown in Figure 2, hot air outlets 1a, 1
The hot air supplied to the heat treatment chamber from b, 1c... is normally passed through a hot air heater 13 and fan 14 provided outside the heat treatment chamber, through intake ports 2a, 2b, 2c..., hot air outlets 1a, 1b, 1c... and ducts. Connected and used in circulation. Slits 6a, 6b, 6c are provided before and after the seal chambers 4 and 5 so that the yarn can pass through.
...is provided. The opening size of this slit is preferably as narrow as possible without coming into contact with the yarn, and from this point it is preferable that the slit be adjustable in the vertical direction.
さらに、仕切板７ａ，７ｂ…及び８ａ，８ｂ…
により形成される小室′，′，′…及び′，
′，′…には夫々排気口９ａ，９ｂ，９ｃ…及
び１０ａ，１０ｂ，１０ｃが設けられており、炉
外に設置したフアン１１及び１２により個別に排
気出来る構造となつている。 Furthermore, partition plates 7a, 7b... and 8a, 8b...
The chambers formed by ′, ′, ′... and ′,
are provided with exhaust ports 9a, 9b, 9c, . . . and 10a, 10b, 10c, respectively, and are configured to be individually evacuated by fans 11 and 12 installed outside the furnace.
熱風吹き出し口１ａ，１ｂ，１ｃ…及び吸気口
２ａ，２ｂ，２ｃ…を本発明の構造とすることに
より、炉内における熱風の流れを容易に糸条走行
方向と実質的に平行な流れとすることができ、シ
ート状に並列した多数の糸条を耐炎化処理しても
激しい糸条間摩擦を防げるため、この工程におけ
る擦過による糸条の毛羽立ちや糸切れ現象がほと
んど起こらないものとすることができる。また、
熱処理室内に仕切板を設けることにより仕切板で
区画される熱処理室内の空間，，…の雰囲
気の熱対流を従来開発されてきた炉に比べ著しく
低いものとすることができるので、偏流のないよ
り均一な流れとなし得るだけでなく、炉内の上下
方向の温度の不均一性をも低減できる。 By making the hot air outlets 1a, 1b, 1c... and the intake ports 2a, 2b, 2c... into the structure of the present invention, the flow of hot air in the furnace can be easily made to flow substantially parallel to the yarn running direction. Even if a large number of yarns lined up in a sheet form are flame-retardantly treated, severe friction between the yarns can be prevented, so the phenomenon of thread fuzzing and yarn breakage due to friction in this process should hardly occur. Can be done. Also,
By installing a partition plate in the heat treatment chamber, the heat convection in the atmosphere of the heat treatment chamber partitioned by the partition plate can be significantly lowered compared to conventionally developed furnaces, so there is no biased flow. Not only can a uniform flow be achieved, but also the non-uniformity of temperature in the vertical direction within the furnace can be reduced.
一般に、熱処理室内の圧力と炉外の圧力との圧
力差は、気体温度の違いにより生ずる熱処理室内
外の浮力差の影響で炉の高さ方向に変化する。そ
のため、熱処理室の上部スリツトからは熱風が炉
外に逃げやすく、又、下部スリツトからは外部気
体が熱処理室内へ流入し易いが、本発明の熱処理
炉は前述した如きシール室４及び５を備えている
ため、シール室内の圧力を熱処理室内の圧力より
小さくすることができるので熱処理室内の圧力変
動に伴う熱処理室内への外部気体の流入による熱
処理室の温度変化を極めて少なくすることができ
るのである。 Generally, the pressure difference between the pressure inside the heat treatment chamber and the pressure outside the furnace changes in the height direction of the furnace due to the difference in buoyancy between the outside and outside of the heat treatment chamber caused by the difference in gas temperature. Therefore, hot air tends to escape from the upper slit of the heat treatment chamber to the outside of the furnace, and external gas tends to flow into the heat treatment chamber from the lower slit. However, the heat treatment furnace of the present invention is equipped with the seal chambers 4 and 5 as described above. As a result, the pressure inside the sealing chamber can be made lower than the pressure inside the heat treatment chamber, making it possible to minimize temperature changes in the heat treatment chamber due to external gas flowing into the heat treatment chamber due to pressure fluctuations within the heat treatment chamber. .
さらに、シール室にも仕切板を設けてあるので
各シール小室に夫々独立した排気機構あるいは圧
力調整機構を備えることにより各スリツト位置に
おける熱処理室内とシール室内の圧力差を個別に
制御できるので前述の熱処理室内外の浮力差の影
響による熱処理室への外気の流入及び熱風の過度
の流出を抑制することができ、従来にない温度の
均一性に優れた熱処理炉とすることに成功したの
である。 Furthermore, since the sealing chamber is also provided with a partition plate, each sealing chamber is equipped with an independent exhaust mechanism or pressure adjustment mechanism, so that the pressure difference between the heat treatment chamber and the sealing chamber at each slit position can be individually controlled. It was possible to suppress the inflow of outside air into the heat treatment chamber and the excessive outflow of hot air due to the difference in buoyancy between the outside and outside of the heat treatment chamber, and succeeded in creating a heat treatment furnace with unprecedented temperature uniformity.
本発明の熱処理炉は前述したごとき構造を有す
るため、熱処理室を所定の温度に加熱した際の温
度コントロール性に極めて優れていると共に、風
向きが糸条の走行方向と平行に保たれているため
走行糸条に無理な力が加えられることを防止する
ことができ、シート状に編成した糸条を熱処理し
た際にも糸条間の異常な摩擦による毛羽や糸切れ
の発生を防ぎ得るものであり、特に炭素繊維製造
工程において採用する耐炎化炉として用いた場
合、その性能を高く発揮することができるもので
ある。
Since the heat treatment furnace of the present invention has the above-described structure, it has excellent temperature controllability when heating the heat treatment chamber to a predetermined temperature, and the wind direction is kept parallel to the running direction of the yarn. It can prevent excessive force from being applied to the running yarn, and even when yarn knitted into a sheet is heat-treated, it can prevent fuzz and yarn breakage due to abnormal friction between the yarns. In particular, when used as a flameproofing furnace employed in the carbon fiber manufacturing process, it can exhibit high performance.
第１図は本発明による炭素繊維製造用の横型熱
処理炉の概略構造を示す立断面図、第２図は第１
図を上から見た平面断面図である。
１ａ，１ｂ，１ｃ……熱風吹き出し口、２ａ，
２ｂ，２ｃ……吸気口、３ａ，３ｂ……仕切板、
４，５……シール室、６ａ，６ｂ，６ｃ……スリ
ツト、７ａ，７ｂ……仕切板、８ａ，８ｂ……仕
切板、９ａ，９ｂ，９ｃ……排気口、１０ａ，１
０ｂ，１０ｃ……排気口、１１，１２……排気フ
アン、１３……熱風加熱器、１４……フアン、Ａ
……糸条。
FIG. 1 is an elevational sectional view showing the schematic structure of a horizontal heat treatment furnace for manufacturing carbon fiber according to the present invention, and FIG.
FIG. 3 is a plan sectional view of the figure viewed from above. 1a, 1b, 1c...Hot air outlet, 2a,
2b, 2c...Intake port, 3a, 3b...Partition plate,
4, 5... Seal chamber, 6a, 6b, 6c... Slit, 7a, 7b... Partition plate, 8a, 8b... Partition plate, 9a, 9b, 9c... Exhaust port, 10a, 1
0b, 10c... Exhaust port, 11, 12... Exhaust fan, 13... Hot air heater, 14... Fan, A
...Thread.
Claims (1)
熱風を吹き出す熱風吹き出し口１と該熱風を熱処
理室外に排出する為の吸気口２とを糸条の通路の
上下に備え、かつ、糸条の通路間を区画するよう
に熱処理室内に仕切板３を設けた熱処理室と、熱
処理室の出入口部にスリツト６を有するシール室
４，５を設け、該シール室内の糸条の通路を区画
するようにシール室内に仕切板７，８を設けたこ
とを特徴とする炭素繊維製造用の横型熱処理炉。1. A hot air outlet 1 for blowing hot air into the heat treatment chamber in a direction parallel to the direction in which the yarn is transferred and an air inlet 2 for discharging the hot air to the outside of the heat treatment chamber are provided above and below the yarn path, and A heat treatment chamber is provided with a partition plate 3 in the heat treatment chamber to partition the passages between the two, and seal chambers 4 and 5 having slits 6 at the entrance and exit of the heat treatment chamber are provided to divide the passage of the yarn within the seal chamber. A horizontal heat treatment furnace for producing carbon fiber, characterized in that partition plates 7 and 8 are provided in the sealing chamber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7335486A JPS62228867A (en) | 1986-03-31 | 1986-03-31 | Horizontal type heat treating furnace for manufacturing carbon fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7335486A JPS62228867A (en) | 1986-03-31 | 1986-03-31 | Horizontal type heat treating furnace for manufacturing carbon fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62228867A JPS62228867A (en) | 1987-10-07 |
| JPH034834B2 true JPH034834B2 (en) | 1991-01-24 |
Family
ID=13515742
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7335486A Granted JPS62228867A (en) | 1986-03-31 | 1986-03-31 | Horizontal type heat treating furnace for manufacturing carbon fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62228867A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06173123A (en) * | 1992-09-14 | 1994-06-21 | Nippon Steel Corp | Method for sealing infusibilizing furnace for pitch-based carbon fiber and apparatus therefor |
| JPH06173124A (en) * | 1992-09-14 | 1994-06-21 | Nippon Steel Corp | Method for regulating atmosphere between infusibilizing furnace and carbonizing furnace and apparatus therefor |
| CA2409620C (en) | 2001-03-26 | 2009-09-15 | Toho Tenax Co., Ltd. | Heat treatment apparatus for oxidation and operating method of the apparatus |
| JP6372095B2 (en) * | 2014-03-06 | 2018-08-15 | 三菱ケミカル株式会社 | Carbon fiber manufacturing method |
-
1986
- 1986-03-31 JP JP7335486A patent/JPS62228867A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62228867A (en) | 1987-10-07 |
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