JP2000211937A - Cleaning method for burner for optical fiber preform - Google Patents
Cleaning method for burner for optical fiber preformInfo
- Publication number
- JP2000211937A JP2000211937A JP11016840A JP1684099A JP2000211937A JP 2000211937 A JP2000211937 A JP 2000211937A JP 11016840 A JP11016840 A JP 11016840A JP 1684099 A JP1684099 A JP 1684099A JP 2000211937 A JP2000211937 A JP 2000211937A
- Authority
- JP
- Japan
- Prior art keywords
- burner
- optical fiber
- cleaning
- fiber preform
- cleaning liquid
- 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.)
- Pending
Links
Landscapes
- Cleaning By Liquid Or Steam (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
(57)【要約】
【課題】光ファイバプリフォーム用バーナの先端部に付
着した金属酸化物や不純異物を除去するための洗浄方法
を提供する。
【解決手段】光ファイバプリフォーム用バーナ１の洗浄
方法は、可燃性ガスの流れる外筒２内に、支燃性ガスの
流れる複数の内管３が挿入されたバーナの少なくとも火
炎口４近傍を、超音波振動を与えた洗浄液８に浸漬して
洗浄することを特徴としている。
An object of the present invention is to provide a cleaning method for removing metal oxides and impurity particles adhering to the tip of an optical fiber preform burner. A method of cleaning a burner for an optical fiber preform includes a method of cleaning a burner in which a plurality of inner tubes through which a combustible gas flows are inserted into an outer tube through which a combustible gas flows. It is characterized in that it is immersed in a cleaning liquid 8 to which ultrasonic vibration is applied for cleaning.
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、光ファイバを得る
ための原材となる光ファイバプリフォームの延伸や、光
ファイバプリフォーム表面の平滑化の際に用いられるバ
ーナの洗浄方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning a burner used for stretching an optical fiber preform as a raw material for obtaining an optical fiber and smoothing the surface of the optical fiber preform. .
【０００２】[0002]
【従来の技術】光ファイバは、石英ガラスを主成分とす
る光ファイバ母材を原材として、製造されている。光フ
ァイバ母材を加熱して所定径に延伸したものは、光ファ
イバプリフォームと呼ばれる。これを線引機で線引きす
ると光ファイバが得られる。2. Description of the Related Art An optical fiber is manufactured using an optical fiber preform mainly composed of quartz glass as a raw material. An optical fiber preform heated and drawn to a predetermined diameter is called an optical fiber preform. When this is drawn by a drawing machine, an optical fiber is obtained.
【０００３】この光ファイバプリフォームを延伸した
り、その表面を平滑にするため熱処理する際には、バー
ナにより火炎で加熱する方法がとられている。[0003] When the optical fiber preform is stretched or heat-treated to smooth its surface, a method of heating with a burner using a flame is used.
【０００４】バーナは、可燃性ガスの流れる外筒内に、
支燃性ガスの流れる複数の内管が挿入されたものが用い
られる。この外筒や内管の材質は、耐熱性に優れたステ
ンレス鋼が使用されている。しかしバーナ先端の表面は
火炎により４００〜７００℃の高温になっているので、
バーナを長時間使用すると、バーナ先端表面に金属酸化
物が生じ、徐々に浮遊性の微粒子となる。光ファイバー
プリフォームの製造や熱処理の際に、この金属酸化物の
微粒子や、バーナに付着したガラス微粒子等の不純異物
が飛散し、光ファイバプリフォームの表面に付着する
と、表層部をヤスリ等で研磨しなければならない。研磨
すると光ファイバープリフォームの石英クラッド部とコ
ア部との比率が変わり、光ファイバの光伝送特性を劣化
させてしまう。[0004] The burner is provided in an outer cylinder through which combustible gas flows.
The one into which a plurality of inner pipes through which the supporting gas flows is used. As the material of the outer tube and the inner tube, stainless steel having excellent heat resistance is used. However, the surface of the burner tip is heated to 400-700 ° C by the flame,
When the burner is used for a long time, metal oxides are generated on the tip surface of the burner and gradually become buoyant fine particles. When manufacturing or heat treating an optical fiber preform, impurity particles such as metal oxide fine particles and glass fine particles attached to a burner are scattered and adhere to the surface of the optical fiber preform, and the surface layer is polished with a file or the like. Must. Polishing changes the ratio between the quartz clad portion and the core portion of the optical fiber preform, and deteriorates the optical transmission characteristics of the optical fiber.
【０００５】[0005]
【発明が解決しようとする課題】高品質の光ファイバー
プリフォームを製造するためには、清浄なバーナを使用
する必要がある。The production of high quality optical fiber preforms requires the use of clean burners.
【０００６】本発明は前記の課題を解決するためなされ
たもので、光ファイバプリフォーム用バーナの先端部の
金属酸化物や付着不純異物を除去するための洗浄方法を
提供することを目的とする。SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a cleaning method for removing metal oxides and adhered impurities at the tip of an optical fiber preform burner. .
【０００７】[0007]
【課題を解決するための手段】前記の目的を達成するた
めになされた本発明の光ファイバプリフォーム用バーナ
の洗浄方法は、実施例に対応する図１を参照して説明す
ると、可燃性ガスの流れる外筒２内に、支燃性ガスの流
れる複数の内管３が挿入されたバーナ１の少なくとも火
炎口４近傍を、超音波振動を与えた洗浄液８に浸漬して
洗浄することを特徴としている。A method of cleaning a burner for an optical fiber preform according to the present invention, which has been made to achieve the above object, will be described with reference to FIG. At least the vicinity of the flame port 4 of the burner 1 in which the plurality of inner tubes 3 through which the combustion-supporting gas flows is inserted into the outer cylinder 2 through which water flows, is immersed in a cleaning liquid 8 which is subjected to ultrasonic vibration to be cleaned. And
【０００８】超音波振動は、振動周波数１０ｋＨｚ〜１
００ｋＨｚであることが好ましい。The ultrasonic vibration has a vibration frequency of 10 kHz to 1
Preferably, it is 00 kHz.
【０００９】洗浄液８が、フッ化水素酸と硝酸とを含ん
でいることが好ましい。フッ化水素酸は、外筒２および
内管３の表面の金属酸化物を溶解させる作用を有してい
る。外筒２および内管３の材質がステンレス鋼である場
合、ステンレス鋼が含んでいる鉄やクロムやニッケル
は、その表面に硝酸の作用による不動態薄膜を形成する
ため、表面酸化が起こりにくくなる。Preferably, the cleaning liquid 8 contains hydrofluoric acid and nitric acid. Hydrofluoric acid has an action of dissolving the metal oxide on the surfaces of the outer tube 2 and the inner tube 3. When the material of the outer tube 2 and the inner tube 3 is stainless steel, the surface oxidation of iron, chromium and nickel contained in the stainless steel is less likely to occur because a passive thin film is formed on the surface by the action of nitric acid. .
【００１０】洗浄液８は、水溶液であることが好ましい
が、水溶性有機溶媒を含んでいてもよい。水溶性有機溶
媒は、具体的には、アルコール、アセトン、アセトニト
リル、テトラヒドロフランが挙げられる。The washing liquid 8 is preferably an aqueous solution, but may contain a water-soluble organic solvent. Specific examples of the water-soluble organic solvent include alcohol, acetone, acetonitrile, and tetrahydrofuran.
【００１１】光ファイバプリフォーム用バーナの洗浄方
法は、バーナ１を、フッ化水素酸を含む洗浄液８に浸漬
後、硝酸を含む別な洗浄液８に浸漬する方法であっても
よい。The method for cleaning a burner for an optical fiber preform may be a method in which the burner 1 is immersed in a cleaning liquid 8 containing hydrofluoric acid and then immersed in another cleaning liquid 8 containing nitric acid.
【００１２】フッ化水素酸と硝酸の混液に超音波振動を
与えながら、バーナを洗浄すると、バーナの先端が酸化
された金属酸化物を除去できるとともに、バーナに付着
したガラス微粒子等の不純異物を除去することができ
る。When the burner is cleaned while applying ultrasonic vibration to the mixed solution of hydrofluoric acid and nitric acid, the burner tip can remove the oxidized metal oxide and remove foreign impurities such as glass particles adhered to the burner. Can be removed.
【００１３】なお、超音波発振器７からは、１Ｗ／ｃｍ
２〜２ｋＷ／ｃｍ２の強度の超音波が発振されることが
好ましい。The ultrasonic oscillator 7 outputs 1 W / cm
Preferably, an ultrasonic wave having an intensity of 2 to 2 kW / cm 2 is oscillated.
【００１４】[0014]
【発明の実施の形態】以下、本発明の実施例を詳細に説
明する。図１には、本発明を適用する光ファイバプリフ
ォーム用バーナの洗浄方法の実施例の概略図が示されて
いる。DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is a schematic view showing an embodiment of a method for cleaning a burner for an optical fiber preform to which the present invention is applied.
【００１５】光ファイバプリフォーム用バーナ１の洗浄
方法は、超音波発振器７が取り付けられ、洗浄液８が入
った超音波洗浄用水槽９を用いて行われる。The method for cleaning the optical fiber preform burner 1 is performed by using an ultrasonic cleaning water tank 9 in which an ultrasonic oscillator 7 is attached and a cleaning liquid 8 is contained.
【００１６】一方、光ファイバープリフォーム用バーナ
１は、ステンレス製であり、水素ガスの流れる内径３０
ｍｍの外筒２の中に、酸素ガスの流れる内径１ｍｍで外
径３ｍｍの内管３を有している。外筒２は水素ガス導入
管５に接続され、全ての内管３は酸素ガス導入管６に繋
がっている。On the other hand, the burner 1 for an optical fiber preform is made of stainless steel, and has an inner diameter 30 through which hydrogen gas flows.
An inner tube 3 having an inner diameter of 1 mm and an outer diameter of 3 mm is provided in an outer cylinder 2 having a diameter of 1 mm. The outer cylinder 2 is connected to a hydrogen gas introduction pipe 5, and all the inner pipes 3 are connected to an oxygen gas introduction pipe 6.
【００１７】洗浄時には、水素ガス導入管５および酸素
ガス導入管６を外界へ開放し、火炎口４を下にしてバー
ナ１を洗浄液８に浸ける。すると外筒２内、および内管
３内の空気は各々水素ガス導入管５、および酸素ガス導
入管６から抜け、洗浄液８が水面の高さまで浸る。超音
波発振器７により超音波を発振させて洗浄を行う。At the time of cleaning, the hydrogen gas introducing pipe 5 and the oxygen gas introducing pipe 6 are opened to the outside, and the burner 1 is immersed in the cleaning liquid 8 with the flame port 4 down. Then, the air in the outer cylinder 2 and the air in the inner pipe 3 escape from the hydrogen gas introducing pipe 5 and the oxygen gas introducing pipe 6, respectively, and the cleaning liquid 8 is immersed to the level of the water surface. Cleaning is performed by oscillating ultrasonic waves by the ultrasonic oscillator 7.
【００１８】前記の実施例にしたがって、光ファイバプ
リフォーム用バーナの洗浄を行った。According to the above embodiment, the burner for the optical fiber preform was cleaned.
【００１９】超音波洗浄槽９には、１０％のフッ化水素
酸と３％の硝酸の水溶液である洗浄液８が入っている。
一方、光ファイバプリフォーム製造に用いたステンレス
製のバーナ１には、火炎口４近傍に金属酸化物が付着し
ている。このバーナ１の火炎口４近傍を洗浄液に浸け、
出力５００Ｗの超音波発振器により振動周波数の超音波
を３０分間発振させて洗浄処理を行った。バーナ１を引
き上げ、純水で表面に残留した洗浄液を流し去り、乾燥
した。外筒２および内管３の先端部をルーペにより観察
したところ、金属酸化物および不純異物は認められず、
金属光沢を呈していた。この洗浄処理したバーナを用
い、光ファイバプリフォームの表面を熱処理したとこ
ろ、全加工本数に対する、不純異物が付着していた本数
の比率は６％であった。The ultrasonic cleaning tank 9 contains a cleaning liquid 8 which is an aqueous solution of 10% hydrofluoric acid and 3% nitric acid.
On the other hand, a metal oxide adheres to the vicinity of the flame port 4 on the burner 1 made of stainless steel used for manufacturing the optical fiber preform. Immerse the vicinity of the flame port 4 of this burner 1 in the cleaning liquid,
A cleaning process was performed by oscillating ultrasonic waves having a vibration frequency for 30 minutes using an ultrasonic oscillator having an output of 500 W. The burner 1 was pulled up, the cleaning liquid remaining on the surface was washed away with pure water, and dried. When the distal ends of the outer tube 2 and the inner tube 3 were observed with a loupe, no metal oxides or impure foreign matters were found.
It had a metallic luster. When the surface of the optical fiber preform was heat-treated by using the burner subjected to the cleaning treatment, the ratio of the number of impure foreign matters to the total number of processed pieces was 6%.
【００２０】比較のため洗浄処理を行っていないバーナ
を用い、光ファイバプリフォームの表面を熱処理する
と、同比率は１５％であり、不純異物の付着が多かっ
た。For comparison, when the surface of the optical fiber preform was heat-treated using a burner that had not been subjected to a cleaning treatment, the same ratio was found to be 15%, indicating that a large amount of impurity was attached.
【００２１】[0021]
【発明の効果】以上、詳細に説明したように本発明の光
ファイバプリフォーム用バーナの洗浄方法によれば、バ
ーナの先端に生じた金属酸化物や付着異物を除去するこ
とができる。洗浄されたバーナを用いて光ファイバープ
リフォームの製造、および表面加工を行う際、異物の付
着がないので、高品質の光ファイバプリフォームが得ら
れる。As described above in detail, according to the method for cleaning a burner for an optical fiber preform of the present invention, it is possible to remove metal oxides and attached foreign matter generated at the tip of the burner. When manufacturing and surface processing the optical fiber preform using the cleaned burner, there is no adhesion of foreign matter, and thus a high quality optical fiber preform can be obtained.
【図１】本発明を適用する光ファイバプリフォーム用バ
ーナの洗浄方法の実施例を示す概略図である。FIG. 1 is a schematic view showing an embodiment of a method for cleaning a burner for an optical fiber preform to which the present invention is applied.
１はバーナ、２は外筒、３は内管、４は火炎口、５は水
素導入管、６は酸素導入管、７は超音波発振器、８は洗
浄液、９は超音波洗浄用水槽である。1 is a burner, 2 is an outer cylinder, 3 is an inner tube, 4 is a flame port, 5 is a hydrogen inlet tube, 6 is an oxygen inlet tube, 7 is an ultrasonic oscillator, 8 is a cleaning liquid, and 9 is an ultrasonic cleaning water tank. .
───────────────────────────────────────────────────── フロントページの続き (72)発明者 鈴木 真二 群馬県安中市磯部２丁目13番１号 信越化 学工業株式会社精密機能材料研究所内 (72)発明者 島田 忠克 群馬県安中市磯部２丁目13番１号 信越化 学工業株式会社精密機能材料研究所内 (72)発明者 平沢 秀夫 群馬県安中市磯部２丁目13番１号 信越化 学工業株式会社精密機能材料研究所内 Ｆターム(参考） 3B201 AA47 AB42 BB02 BB84 BB96 CB12 CB15 4G021 EB13 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinji Suzuki 2-13-1, Isobe, Annaka-shi, Gunma Shin-Etsu Kagaku Kogyo Co., Ltd.Precision Functional Materials Laboratory (72) Inventor Tadakatsu Shimada Annaka-shi, Gunma 2-13-1, Isobe Shin-Etsu Chemical Industry Co., Ltd. Precision Functional Materials Research Laboratory (72) Inventor Hideo Hirasawa 2-13-1, Isobe, Annaka-shi, Gunma Prefecture Shin-Etsu Chemical Co., Ltd. Precision Functional Materials Research Laboratory F-term (Reference) 3B201 AA47 AB42 BB02 BB84 BB96 CB12 CB15 4G021 EB13
Claims (4)
ガスの流れる複数の内管が挿入されたバーナの少なくと
も火炎口近傍を、超音波振動を与えた洗浄液に浸漬して
洗浄することを特徴とする光ファイバプリフォーム用バ
ーナの洗浄方法。1. A burner in which a plurality of inner tubes through which a combustible gas flows is inserted into an outer cylinder through which a combustible gas flows, and at least a vicinity of a flame port of the burner is immersed in a cleaning liquid subjected to ultrasonic vibration to be cleaned. A method for cleaning a burner for an optical fiber preform, the method comprising:
Ｈｚ〜１００ｋＨｚであることを特徴とする請求項１に
記載の光ファイバプリフォーム用バーナの洗浄方法。2. The ultrasonic vibration has a vibration frequency of 10 k.
The method for cleaning a burner for an optical fiber preform according to claim 1, wherein the frequency is in the range of Hz to 100 kHz.
を含んでいることを特徴とする請求項１に記載の光ファ
イバプリフォーム用バーナの洗浄方法。3. The method for cleaning a burner for an optical fiber preform according to claim 1, wherein said cleaning liquid contains hydrofluoric acid and nitric acid.
記洗浄液に浸漬後、硝酸を含む別な前記洗浄液に浸漬す
ることを特徴とする請求項１に記載の光ファイバプリフ
ォーム用バーナの洗浄方法。4. The cleaning of a burner for an optical fiber preform according to claim 1, wherein the burner is immersed in the cleaning liquid containing hydrofluoric acid and then immersed in another cleaning liquid containing nitric acid. Method.
Priority Applications (16)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11016840A JP2000211937A (en) | 1999-01-26 | 1999-01-26 | Cleaning method for burner for optical fiber preform |
| DE69931825T DE69931825T8 (en) | 1998-11-05 | 1999-11-03 | Method and apparatus for producing a preform and an optical fiber from the preform |
| EP99250390A EP0999189B1 (en) | 1998-11-05 | 1999-11-03 | Process and apparatus for drawing a preform and for drawing an optical fibre from the drawn preform |
| DE1999638158 DE69938158T8 (en) | 1998-11-05 | 1999-11-03 | A method of making a preform and an optical fiber from the preform |
| EP03090252A EP1364918B1 (en) | 1998-11-05 | 1999-11-03 | A method and apparatus for manufacturing a preform and optical fibre from the preform |
| DE69924447T DE69924447T2 (en) | 1998-11-05 | 1999-11-03 | A method and apparatus for drawing a preform and drawing an optical fiber from the drawn preform |
| EP03090253A EP1364919B1 (en) | 1998-11-05 | 1999-11-03 | Method for manufacturing a preform and optical fibre from the preform |
| US09/434,280 US6386001B1 (en) | 1998-11-05 | 1999-11-05 | Optical fiber manufacture method including elongating a preform in a vertical direction and a horizontal direction |
| KR1019990048941A KR100551100B1 (en) | 1998-11-05 | 1999-11-05 | Optical fiber manufacture method, preform manufacture method, and preform manufacture apparatus |
| TW90126003A TW548247B (en) | 1998-11-05 | 1999-12-10 | Optical fiber manufacture method, preform manufacture method, and preform manufacture apparatus |
| US10/158,801 US6848276B2 (en) | 1998-11-05 | 2002-06-03 | Optical fiber manufacture method, preform manufacture method, and preform manufacture apparatus |
| US10/158,803 US20020144520A1 (en) | 1998-11-05 | 2002-06-03 | Optical fiber manufacture method, preform manufacture method, and preform manufacture apparatus |
| US10/158,843 US20020139149A1 (en) | 1998-11-05 | 2002-06-03 | Optical fiber manufacture method, preform manufacture method, and preform manufacture apparatus |
| US10/158,804 US20020152772A1 (en) | 1998-11-05 | 2002-06-03 | Optical fiber manufacture method, preform manufacture method, and preform manufacture apparatus |
| US10/158,904 US6779362B2 (en) | 1998-11-05 | 2002-06-03 | Method of making an optical fiber preform where a second elongation is based on a mark on a glass rod |
| US11/046,889 US20050132753A1 (en) | 1998-11-05 | 2005-02-01 | Optical fiber manufacture method, preform manufacture method, and preform manufacture apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11016840A JP2000211937A (en) | 1999-01-26 | 1999-01-26 | Cleaning method for burner for optical fiber preform |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000211937A true JP2000211937A (en) | 2000-08-02 |
Family
ID=11927416
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11016840A Pending JP2000211937A (en) | 1998-11-05 | 1999-01-26 | Cleaning method for burner for optical fiber preform |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000211937A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2794374C1 (en) * | 2022-07-26 | 2023-04-17 | Общество с ограниченной ответственностью "Александра-Плюс" | Method for cleaning gas burners using ultrasonic vibrations |
| CN117732786A (en) * | 2023-12-21 | 2024-03-22 | 华能(泰安)光电科技有限公司 | Optical fiber perform surface treatment cleaning device |
-
1999
- 1999-01-26 JP JP11016840A patent/JP2000211937A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2794374C1 (en) * | 2022-07-26 | 2023-04-17 | Общество с ограниченной ответственностью "Александра-Плюс" | Method for cleaning gas burners using ultrasonic vibrations |
| CN117732786A (en) * | 2023-12-21 | 2024-03-22 | 华能(泰安)光电科技有限公司 | Optical fiber perform surface treatment cleaning device |
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