JPS6356178B2 - - Google Patents
Info
- Publication number
- JPS6356178B2 JPS6356178B2 JP8589180A JP8589180A JPS6356178B2 JP S6356178 B2 JPS6356178 B2 JP S6356178B2 JP 8589180 A JP8589180 A JP 8589180A JP 8589180 A JP8589180 A JP 8589180A JP S6356178 B2 JPS6356178 B2 JP S6356178B2
- Authority
- JP
- Japan
- Prior art keywords
- base material
- furnace
- porous glass
- preheating furnace
- glass base
- 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
- 239000000463 material Substances 0.000 claims description 35
- 239000005373 porous glass Substances 0.000 claims description 31
- 238000010438 heat treatment Methods 0.000 claims description 25
- 239000011521 glass Substances 0.000 claims description 14
- 239000013307 optical fiber Substances 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 238000007380 fibre production Methods 0.000 claims 1
- 239000007789 gas Substances 0.000 description 9
- 239000002245 particle Substances 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- 238000003786 synthesis reaction Methods 0.000 description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 238000005253 cladding Methods 0.000 description 4
- 208000005156 Dehydration Diseases 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000018044 dehydration Effects 0.000 description 3
- 238000006297 dehydration reaction Methods 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 229910003902 SiCl 4 Inorganic materials 0.000 description 2
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- RLOWWWKZYUNIDI-UHFFFAOYSA-N phosphinic chloride Chemical compound ClP=O RLOWWWKZYUNIDI-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000004017 vitrification Methods 0.000 description 2
- 229910005793 GeO 2 Inorganic materials 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 229910000953 kanthal Inorganic materials 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/012—Manufacture of preforms for drawing fibres or filaments
- C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
- C03B37/01466—Means for changing or stabilising the diameter or form of tubes or rods
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Description
【発明の詳細な説明】
本発明は光フアイバ用母材の製造方法及び製造
装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for manufacturing a base material for optical fiber.
光フアイバ用母材の製造方法の１種のVAD法
では第１図に示すような装置により丸棒状の多孔
質ガラス母材および透明母材を製造する。 In the VAD method, which is one type of method for manufacturing optical fiber preforms, round bar-shaped porous glass preforms and transparent preforms are manufactured using an apparatus as shown in FIG.
第１図において、コア用ガラス微粒子合成トー
チ１、クラツド用ガラス粒子合成トーチ２により
形成されたガラス微粒子を出発部材３の端部に堆
積させることにより多孔質ガラス母材４を成長さ
せる。多孔質ガラス母材４は回転引上装置１０に
より毎分10〜20回程度の速度で回転させながら、
多孔質ガラス母材の成長に合わせて上方に引き上
げられる。多孔質ガラス母材は、上方に設けられ
た加熱炉５を通過するにつれて脱泡され、透明ガ
ラス化され透明母材６となる。加熱炉５は、主に
ヒータ７および炉芯管８より構成されており、炉
芯管８の内部には多孔質ガラス母材中のH2O分
子やOH基を除くための脱水処理用ガスが供給口
９を通して送り込まれる。１１は反応容器、１２
は排ガス処理装置を示す。 In FIG. 1, glass particles formed by a core glass particle synthesis torch 1 and a cladding glass particle synthesis torch 2 are deposited on the end of a starting member 3 to grow a porous glass base material 4. The porous glass base material 4 is rotated at a speed of about 10 to 20 times per minute by the rotary pulling device 10, while
It is pulled upward as the porous glass base material grows. The porous glass base material is degassed as it passes through a heating furnace 5 provided above, and becomes transparent vitrified to become a transparent base material 6. The heating furnace 5 is mainly composed of a heater 7 and a furnace core tube 8, and inside the furnace core tube 8 is a dehydration treatment gas for removing H 2 O molecules and OH groups in the porous glass base material. is fed through the supply port 9. 11 is a reaction container, 12
indicates an exhaust gas treatment device.
多孔質ガラス母材を透明ガラス化するためには
1500℃程度の高温が必要であり、炉芯管８として
は高温度および脱水処理用ガスの腐蝕性に耐える
ために高純度アルミナや石英ガラスの材質が用い
られている。多孔質ガラス母材の直径は普通60mm
程度、炉芯管の内径は普通90mm程度である。 To convert porous glass base material into transparent glass
A high temperature of about 1500° C. is required, and the furnace core tube 8 is made of high-purity alumina or quartz glass in order to withstand the high temperature and the corrosivity of the dehydration gas. The diameter of the porous glass base material is usually 60mm.
The inner diameter of the furnace core tube is usually about 90mm.
光フアイバの低価格化のためには直径の大きい
多孔質ガラス母材を成長させ大型の透明母材を得
るのが有効であるが、従来、多孔質ガラス母材の
直径が90mmを越えると炉芯管８の寸法もそれに合
わせて太くしなければならず、大口径の高純度ア
ルミナ炉芯管がきわめて高価である。また1500℃
程度の高温のためひび割れるという大きな問題点
があつた。石英ガラス炉芯管の場合には、1500℃
が軟化点以上であるため大口径化に伴ない変形や
破裂等が生じ、消耗が激しいという欠点があつ
た。 In order to reduce the cost of optical fiber, it is effective to grow a porous glass base material with a large diameter to obtain a large transparent base material, but conventionally, if the diameter of the porous glass base material exceeds 90 mm, The dimensions of the core tube 8 must be increased accordingly, and a large-diameter, high-purity alumina furnace core tube is extremely expensive. Also 1500℃
A major problem was that it cracked due to the extremely high temperatures. 1500℃ for quartz glass furnace core tube
Since the diameter is above the softening point, deformation and rupture occur as the diameter increases, leading to severe wear and tear.
本発明では、多孔質ガラス母材を透明ガラス化
するには1500℃程度の高温が必要であるが、多孔
質ガラス母材を単に収縮するには1300℃程度の温
度でよいことに着目し、内口径の大きな収縮用の
予備加熱炉と内口径の小さな高温加熱炉に順次多
孔質ガラス母材を通すことにより、上記の問題点
を解決して直径の大きな多孔質ガラス母材の透明
ガラス化を可能にすることを目的とするものであ
る。 In the present invention, we focused on the fact that a high temperature of about 1500°C is required to turn a porous glass base material into transparent vitrification, but a temperature of about 1300°C is sufficient to simply shrink the porous glass base material, By sequentially passing the porous glass base material through a shrinkage preheating furnace with a large inner diameter and a high temperature heating furnace with a small inner diameter, the above problems can be solved and the porous glass base material with a large diameter can be made into transparent vitrification. The purpose is to make it possible.
第２図は、本発明の実施例であつて、第１図に
示した装置に対して異なる点は、透明ガラス化用
の加熱炉が、多孔質ガラス母材の寸法の収縮のみ
を行なう予備加熱炉５ａと、前記予備加熱炉より
内容の小さい最終的な透明化を行なう高温加熱炉
５ｂから構成されている点である。予備加熱炉５
ａはその中心に円筒形の炉芯管８ａが形成され、
該炉芯管の外周にヒータ７ａが配置されている。
高温加熱炉５ｂはその中心に円筒形の炉芯管８ａ
が形成され、該炉芯管の外周にヒータ７ｂが配置
されており、高温加熱炉の中心軸は、予備加熱炉
の中心軸上にあり、かつ炉芯管８ｂの内径は、炉
芯管８ａの内径より小である。炉芯管８ｂの上方
に脱水処理用ガスの供給口９が形成されている。
１０は回転引上装置を示す。１１は反応容器、１
２は排ガス処理装置を示す。炉芯管８ａ，８ｂは
本実施例では石英ガラス製であり、炉芯管８ａの
内径は150mm，肉厚は５mm，炉芯管８ｂの内径は
70mm，肉厚は５mmである。ヒータ７ａ，７ｂは本
実施例ではカーボン製であり抵抗加熱方式である
が、予備加熱炉５ａでは1300℃程度の加熱温度が
得られれば十分であるので、ヒータ７ａとして炭
化ケイ素発熱体やカンタル線発熱体を用いること
も可能である。ヒータ７ｂとしては高周波加熱カ
ーボンヒータを用いることもできる。 FIG. 2 shows an embodiment of the present invention, which is different from the apparatus shown in FIG. It consists of a heating furnace 5a and a high-temperature heating furnace 5b, which is smaller in content than the preheating furnace and performs final transparency. Preheating furnace 5
A has a cylindrical furnace core tube 8a formed at its center,
A heater 7a is arranged around the outer periphery of the furnace core tube.
The high temperature heating furnace 5b has a cylindrical furnace core tube 8a at its center.
is formed, a heater 7b is arranged around the outer periphery of the furnace core tube, the central axis of the high-temperature heating furnace is on the central axis of the preheating furnace, and the inner diameter of the furnace core tube 8b is equal to that of the furnace core tube 8a. is smaller than the inner diameter of A dehydration gas supply port 9 is formed above the furnace core tube 8b.
10 indicates a rotary pulling device. 11 is a reaction container, 1
2 indicates an exhaust gas treatment device. In this embodiment, the furnace core tubes 8a and 8b are made of quartz glass, and the inner diameter of the furnace core tube 8a is 150 mm, the wall thickness is 5 mm, and the inner diameter of the furnace core tube 8b is 150 mm.
70mm, wall thickness 5mm. In this embodiment, the heaters 7a and 7b are made of carbon and use a resistance heating method, but since it is sufficient to obtain a heating temperature of about 1300°C in the preheating furnace 5a, a silicon carbide heating element or a Kanthal wire is used as the heater 7a. It is also possible to use a heating element. A high frequency heating carbon heater can also be used as the heater 7b.
コア用ガラス微粒子合成トーチ１にガラス原料
としてSiCl4とGeCl4とPOCl3の89：10：１（モル
比）の混合ガスを300ml／分の速度でキヤリアガ
スとともに供給し、酸水素炎により加水分解し、
SiO2−GeO2−P2O5系ガラス微粒子を合成し出発
部材３の端面に堆積させると同時に、側面からク
ラツド用ガラス微粒子合成トーチ２によりSiCl4
−POCl3（99：１）（モル比）（300ml／分）をガラ
ス原料としてSiO2−P2O5系ガラス微粒子を堆積
させ、コア部、クラツド部から成る直径100mmの
多孔質ガラス母材４を50mm／時の速度で成長させ
た。多孔質ガラス母材は1300℃に設定された予備
加熱炉５ａを通過するにつれて60mm程度にまで直
径が緒小された。この仮焼結体４′はやがて1550
℃に設定された高温加熱炉５ｂを通過するにつれ
て完全に脱泡され直径50mmの透明母材６が得られ
た。以上の操作の間、多孔質ガラス母材４の脱水
処理のため供給口９より炉内にHeとCl2との98：
２（モル比）の混合ガスを10／分の割合で供給
した。 A mixed gas of 89:10:1 (mole ratio) of SiCl 4 , GeCl 4 , and POCl 3 as a glass raw material is supplied to the core glass fine particle synthesis torch 1 at a rate of 300 ml/min together with a carrier gas, and hydrolyzed using an oxyhydrogen flame. death,
SiO 2 −GeO 2 −P 2 O 5 series glass particles are synthesized and deposited on the end face of the starting member 3, and at the same time, SiCl 4
- Using POCl 3 (99:1) (mole ratio) (300 ml/min) as a glass raw material, SiO 2 -P 2 O 5 -based glass particles are deposited to create a porous glass base material with a diameter of 100 mm consisting of a core part and a clad part. 4 was grown at a rate of 50 mm/hr. As the porous glass base material passed through the preheating furnace 5a set at 1300°C, its diameter decreased to about 60 mm. This temporary sintered body 4' will eventually become 1550
As it passed through the high-temperature heating furnace 5b set at .degree. C., it was completely degassed and a transparent base material 6 with a diameter of 50 mm was obtained. During the above operations, He and Cl 2 98:
A mixed gas of 2 (molar ratio) was supplied at a rate of 10/min.
本発明で重要な役割を占める予備加熱炉５ａの
設定温度は1250℃〜1450℃の範囲が望ましく、
1250℃よりも設定温度が低い場合には多孔質ガラ
ス母材４の収縮がすみやかに進行せず、上部の高
温加熱炉５ｂの炉芯管８ｂに収縮することが不可
能となつた。また1450℃よりも高い場合には、
150mm程度の大口径の炉芯管８ａの変形や破損、
消耗が激しく、多孔質ガラス母材４の収縮を中途
で断念しなければならなかつた。高温加熱炉は
1550℃程度の温度設定されるが、炉芯管の径が小
さいために炉芯管は長時間の動作に対しても消耗
することなく安定に保たれた。また加熱すべき径
が小さくて済むのでヒータ７ｂ自身の消耗も少な
かつた。 The preheating furnace 5a, which plays an important role in the present invention, preferably has a set temperature in the range of 1250°C to 1450°C.
When the set temperature was lower than 1250° C., the shrinkage of the porous glass base material 4 did not proceed quickly, and it became impossible to shrink the porous glass base material 4 into the furnace core tube 8b of the upper high temperature heating furnace 5b. Also, if the temperature is higher than 1450℃,
Deformation or damage to the furnace core tube 8a, which has a large diameter of about 150 mm,
The consumption was severe, and shrinkage of the porous glass base material 4 had to be abandoned midway through. High temperature heating furnace
The temperature was set at around 1,550℃, but because the diameter of the furnace core tube was small, the furnace core tube remained stable even during long periods of operation without being worn out. Furthermore, since the diameter to be heated is small, the consumption of the heater 7b itself is also reduced.
なお、本実施例では予備加熱炉と高温加熱炉と
が軸方向に配列されている場合について説明した
が、予備加熱炉と高温加熱炉が分離されている場
合も本発明の範囲に含まれることは言うまでもな
い。 In this example, the case where the preheating furnace and the high temperature heating furnace are arranged in the axial direction has been described, but the scope of the present invention also includes a case where the preheating furnace and the high temperature heating furnace are separated. Needless to say.
以上説明したように、本発明では比較的低温で
動作する予備加熱炉と、予備加熱炉より内径の小
さい高温加熱炉を組み合わせることにより多孔質
ガラス母材の収縮，透明ガラス化を行なうので、
多孔質ガラス母材の収縮のみを行なう予備加熱炉
では、炉芯管や発熱体の激しい消耗を招くことな
く、大口径化が容易であり、従来困難であつた90
mmを越える直径の大型多孔質ガラス母材の収縮、
透明ガラス化が容易となり、光フアイバの低価格
化等の実用上の意義が大きい。 As explained above, in the present invention, the porous glass base material is shrunk and made transparent by combining a preheating furnace that operates at a relatively low temperature and a high temperature heating furnace that has an inner diameter smaller than the preheating furnace.
With a preheating furnace that only shrinks the porous glass base material, it is easy to increase the diameter without causing severe wear and tear on the furnace core tube or heating element, which was previously difficult90.
Shrinkage of large porous glass matrix with diameter exceeding mm,
This makes it easier to make transparent glass, which has great practical significance, such as lowering the cost of optical fibers.
また、VAD法により低損失な単一モード光フ
アイバ用母材を得るためには、厚いクラツド部を
設けた多孔質ガラス母材を形成することが要求さ
れ、またジヤケツト用の補助石英ガラス管を用い
ない、いわゆる全合成の光フアイバを作製する場
合にも多孔質ガラス母材の段階で厚いクラツド部
を堆積することが要求されるが、これらの場合必
要な多孔質ガラス母材の直径は100mmを越えるこ
とがあり、本発明の方法は、これらの単一モード
光フアイバ用母材や全合成光フアイバ用母材を製
造するに際してもきわめて有効である。 In addition, in order to obtain a low-loss single-mode optical fiber base material using the VAD method, it is required to form a porous glass base material with a thick cladding, and an auxiliary quartz glass tube for the jacket is required. Even in the case of producing a so-called fully synthetic optical fiber, which does not require the use of glass, it is required to deposit a thick cladding part at the stage of forming a porous glass base material, but in these cases, the diameter of the porous glass base material required is 100 mm. The method of the present invention is extremely effective in manufacturing these single-mode optical fiber preforms and fully synthetic optical fiber preforms.
第１図は従来のVAD法装置、第２図は本発明
の一実施例を示す。
１……コア用ガラス微粒子合成トーチ、２……
クラツド用ガラス微粒子合成トーチ、３……出発
部材、４……多孔質ガラス母材、５……加熱炉、
６……透明母材、７……ヒータ、８……炉芯管、
９……ガス供給口、１０……回転引上げ装置、１
１……反応容器、１２……排ガス処理装置、４′
……仮焼結体、５ａ……予備加熱炉、５ｂ……高
温加熱炉、７ａ，７ｂ……ヒータ、８ａ，８ｂ…
…炉芯管。
FIG. 1 shows a conventional VAD method apparatus, and FIG. 2 shows an embodiment of the present invention. 1...Glass particle synthesis torch for core, 2...
Glass fine particle synthesis torch for cladding, 3... Starting member, 4... Porous glass base material, 5... Heating furnace,
6... Transparent base material, 7... Heater, 8... Furnace core tube,
9...Gas supply port, 10...Rotary pulling device, 1
1...Reaction container, 12...Exhaust gas treatment device, 4'
...Preliminary sintered body, 5a...Preheating furnace, 5b...High temperature heating furnace, 7a, 7b...Heater, 8a, 8b...
...furnace core tube.
Claims (1)
を加熱炉で加熱して透明ガラス化する光フアイバ
用母材の製造方法において、多孔質ガラス母材を
予備加熱炉により加熱して、多孔質ガラス母材の
寸法を縮小した後、前記予備加熱炉に比して内径
の小さい高温加熱炉でより高温に加熱して透明ガ
ラス化することを特徴とする光フアイバ用母材の
製造方法。 ２ 光フアイバ製造用の母材の出発部材が通過す
る通路と、該通路の周囲に配置されており、多孔
質ガラス母材が縮径する温度を与える予備加熱炉
と、該予備加熱炉よりも内径が小さく、多孔質ガ
ラス母材が透明ガラス化する温度を与える高温加
熱炉とを備え、両加熱炉は軸方向に配列されてい
ることを特徴とする光フアイバ用母材の製造装
置。[Claims] 1. A method for producing an optical fiber base material in which a porous glass base material produced by the VAD method is heated in a heating furnace to become transparent vitrified, the porous glass base material being heated in a preheating furnace. After reducing the dimensions of the porous glass preform, the preheating furnace is heated to a higher temperature in a high-temperature heating furnace with a smaller inner diameter than the preheating furnace to form transparent glass. manufacturing method. 2. A passage through which the starting member of the base material for optical fiber production passes, a preheating furnace that is arranged around the passage and provides a temperature at which the porous glass base material shrinks in diameter, and a preheating furnace that is higher than the preheating furnace. An apparatus for manufacturing an optical fiber preform, comprising a high-temperature heating furnace that has a small inner diameter and provides a temperature at which a porous glass preform becomes transparent vitrified, and both heating furnaces are arranged in the axial direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8589180A JPS5711842A (en) | 1980-06-26 | 1980-06-26 | Preparation of base material for optical fiber and preparing apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8589180A JPS5711842A (en) | 1980-06-26 | 1980-06-26 | Preparation of base material for optical fiber and preparing apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5711842A JPS5711842A (en) | 1982-01-21 |
| JPS6356178B2 true JPS6356178B2 (en) | 1988-11-07 |
Family
ID=13871508
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8589180A Granted JPS5711842A (en) | 1980-06-26 | 1980-06-26 | Preparation of base material for optical fiber and preparing apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5711842A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11713272B2 (en) | 2019-03-05 | 2023-08-01 | Corning Incorporated | System and methods for processing an optical fiber preform |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57140328A (en) * | 1981-02-20 | 1982-08-30 | Hitachi Ltd | Manufacture of base material for optical fiber |
| JPS6046940A (en) * | 1983-08-22 | 1985-03-14 | Furukawa Electric Co Ltd:The | Preparation of parent material for optical glass and its device |
| JPS6172644A (en) * | 1984-09-19 | 1986-04-14 | Sumitomo Electric Ind Ltd | Manufacture of optical fiber having low transmission loss |
| JP7205216B2 (en) * | 2018-12-25 | 2023-01-17 | 住友電気工業株式会社 | Manufacturing method of preform for optical fiber |
-
1980
- 1980-06-26 JP JP8589180A patent/JPS5711842A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11713272B2 (en) | 2019-03-05 | 2023-08-01 | Corning Incorporated | System and methods for processing an optical fiber preform |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5711842A (en) | 1982-01-21 |
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