JP3386397B2 - Flame burner for glass processing, glass lathe, and glass processing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention prevents foreign matter from adhering to and mixing with a material to be processed at the time of processing a glass material, particularly a synthetic quartz material, a natural quartz material or an optical fiber preform, for a long time at a high temperature. The present invention relates to a flame burner for glass processing that enables stable operation.

[0002]

2. Description of the Related Art Flames from a flame burner are generally used for processing glass materials. Among the glass materials, the quartz material has a high softening temperature of 1600 ° C. or higher, and when heated with a flame burner for a long time, the temperature of the burner itself also rises, and especially the nozzle at the tip of the burner is oxidized by the high temperature, and the generated oxide is There is a problem that the quality is deteriorated by being sprayed onto the glass material and adhering as a foreign substance.

Normally, stainless steel such as SUS304 and SUS316L is used for the nozzle of the flame burner as a material which is not easily oxidized. These materials hardly oxidize when used for a short time, and the adhesion of metal oxides to the glass material is small, but when used at high temperature for a long time, oxides are generated, which causes foreign substances to adhere to the glass material. .

On the other hand, in the processing of optical fiber preforms, a glass lathe is used, and processing by flame is performed in the steps of drawing, fire polishing and the like. In a glass lathe, a flame burner is usually processed for a long time of 60 minutes or more, so that the flame burner is easily oxidized, and particularly, an oxide is easily generated at the tip of the nozzle, which becomes a thin film and peels off.
It is blown away by the flame and adheres to the surface of the preform. Since such oxides remain as black spots after processing and cooling, the quality of the preform is greatly deteriorated. Therefore, it is necessary to use a material that is not easily oxidized as a material for the flame burner.

As a material for a flame burner that does not generate foreign matter even if it is used for a long time at high temperature, there is a material using a quartz tube, but the quartz tube is vulnerable to mechanical shock, and requires careful use. is there. In particular, when a work (workpiece) is placed directly above the flame burner for processing, when the work falls, the flame burner may be damaged and safety problems such as flammable gas leakage may occur. is there. In addition, when a quartz tube is processed to produce a flame burner, it requires a lot of manual processing, so it is extremely difficult to manufacture it accurately, such as the inner and outer diameters of the tube and the angle of the nozzle. , It is difficult to use.

[0006]

Therefore, in the present invention, a material is selected which is excellent in heat resistance and oxidation resistance, has little deterioration in mechanical strength and the like even at high temperatures, is relatively inexpensive, and is easy to process. A flame burner for glass processing and a glass processing method in which a burner is produced so that an oxide is hardly generated during processing of a glass material, particularly a quartz-based material, and does not adhere to or mix with a workpiece to cause quality deterioration. The main purpose is to provide.

[0007]

In order to solve the above problems, the invention described in claim 1 of the present invention is a flame burner used for processing a glass material, and the material of the nozzle of the flame burner is Ni or SUS310S. A flame burner for glass processing, which is characterized in that

As described above, when a burner using Ni or SUS310S, which has excellent heat resistance and oxidation resistance, is used as the material of the nozzle of the flame burner, the generation of metal oxide at the tip of the nozzle and the thin film peeling off. As a result, it is almost impossible for foreign matter to be attached to or caught in the work piece as a foreign matter, stabilizing the operation and improving quality throughout the glass processing period, improving yield and productivity, and reducing costs. It becomes a flame burner for glass processing that can achieve the above.

In this case, as described in claim 2, the glass material can be synthetic quartz or natural quartz. In this way, even if the glass material to be processed is synthetic quartz or natural quartz, which has a high softening point and is difficult to process, stable operation can be performed relatively easily for a long time, and there is almost no foreign matter and high quality. It becomes a flame burner for glass processing that can obtain a processed product.

Further, as described in claim 3, the glass material can be an optical fiber preform (hereinafter sometimes referred to as an optical fiber preform). In this way, even if the glass material to be processed is an optical fiber preform that requires a long time and highly accurate processing, the length and outer diameter adjustment by stretching the preform and the processing such as fire polishing are long. The flame burner for glass processing can be stably operated for a long time and can obtain a high-quality processed product with almost no foreign matter.

Further, as described in claim 4, the combustible gas used in the flame burner may be hydrogen, and as described in claim 5, the combustion supporting gas may be oxygen. A so-called oxyhydrogen flame in which hydrogen is burned with oxygen is suitable for processing a glass material having a high softening temperature, and if a flame burner made of the material of the present invention is used for processing,
Since it has excellent heat resistance and oxidation resistance, it is a flame burner for glass processing, which can be stably operated for a long time and can obtain a processed product in which almost no foreign matter is generated and adhered.

Further, as described in claim 6, the combustible gas and the auxiliary combustion gas used in the flame burner can be mixed and burned at the tip of the flame burner. With this configuration, ignition inside the flame burner is prevented, and the rise in temperature at the burner tip is suppressed. As a result, the generation of oxides can be prevented, so that foreign matter adheres to the workpiece. This can be further reduced.

Next, the invention according to claim 7 of the present invention comprises the flame burner for glass processing according to any one of claims 1 to 6 Is. If a synthetic quartz material, natural quartz material or optical fiber preform is processed with a flame burner using the glass lathe configured in this way, stable operation can be performed for a long time and a high quality processed product free of foreign matter can be obtained. Can be a glass lathe.

Further, in the invention described in claim 8 of the present invention, when processing a synthetic quartz material, a natural quartz material or an optical fiber preform set on a glass lathe with a flame burner, the material of the nozzle of the burner is used. Ni or SUS
It is a glass processing method characterized by using a flame burner manufactured as 310S.

When the glass material is processed by the flame burner made of Ni or SUS310S, which is excellent in heat resistance and oxidation resistance as the material of the nozzle, the generation of metal oxide at the tip of the nozzle or the thin film becomes a thin film. There is almost no possibility that it will peel off and become attached as foreign matter to the work piece or be caught in the work piece, stabilizing the operation and improving the quality throughout the glass processing period and improving the yield and productivity. Therefore, the cost can be reduced.

[0016]

Embodiments of the present invention will be described below with reference to the accompanying drawings, but the present invention is not limited thereto. Here, FIG. 1 is an (a) external view showing a flame burner for glass processing of the present invention, and (b) a front view of an outlet of a nozzle portion at the tip of the flame burner, and FIG. 2 is provided with a flame burner for glass processing. It is a schematic diagram showing an example of composition of a glass lathe.

The flame burner 20 for glass processing of the present invention comprises:
For example, the external appearance is as shown in FIG. 1A, and the hydrogen introducing pipe 21 for the combustible gas and the oxygen introducing pipe 22 for the supporting gas are used.
The tip of the cylindrical body provided with is a truncated cone-shaped nozzle portion 23, and a high temperature flame is ejected at the tip by an oxyhydrogen flame reaction. As shown in FIG.
As shown in (b), the supporting gas is blown out from several tens of thin pipe-shaped nozzles 25, and the flammable gas is discharged from the gap 26 between the outer case 24 of the nozzle portion 23 and the nozzle 25. Erupted. Oxygen is usually used as the combustion supporting gas, and hydrogen is used as the flammable gas.

In particular, when hydrogen is used as the combustible gas, in order to prevent ignition inside the flame burner, the combustible gas and the auxiliary combustion gas are introduced through separate introduction pipes as described above, It is preferable that the burner gas is fed to the tip of the burner, and the combustible gas and the supporting gas are mixed and burned at the tip of the nozzle of the flame burner so that the flame is blown to the workpiece. The gas flow rate is usually set to about 150 to 500 SLM for hydrogen gas and about 70 to 300 SLM for oxygen gas.

Next, the glass lathe 1 has the above flame burner 2
0 is used to synthesize synthetic quartz material, natural quartz material or optical fiber preform [hereinafter, these may be generically referred to as quartz preform], and a flame burner 20 blows and heats a flame toward the surface of W, It is a machine for stretching to modify the outer diameter and length, removal of dirt, foreign matter, scratches, etc. adhering to the surface of the optical fiber preform, and processing such as final finishing fire polishing (flame polishing).

For example, as shown in FIG. 2, a pair of left and right columns 3 and 4 which are arranged to face each other along the longitudinal direction on the machine base 2 and whose mutual interval is adjustable by a moving mechanism (not shown).
While holding the quartz preform W on the pair of chucks 5 and 5 attached to the front surfaces of the columns 3 and 4 and rotating the quartz preform W around the axis, from one end of the quartz preform W toward the surface of the quartz preform W. ,
Flame burner 2 set on a horizontally movable platform 6.
At 0, a flame is blown and heated, and while measuring the outer diameter with an outer diameter measuring device, the columns 3 and 4 are moved and controlled so as to open the gap between the left and right chucks 5 and 5 so as to obtain a desired diameter, and stretched. It is being processed.

As an example of specific processing conditions, when the preform is heated with a flame and the diameter of expansion and contraction is increased, the flame burner is moved at a speed of about 10 mm / min.
Approximately 10 to process a preform with a length of 1000 mm
It will take 0 minutes. During this time, since the flame was constantly ejected, the tip of the nozzle of the flame burner was heated to about 800 ° C and maintained for 100 minutes, which was a material that was slightly inferior in heat resistance and oxidation resistance, which was conventionally used. For example, when a flame burner made of SUS304, SUS316L or the like is used, even if it is for a short time of about several minutes, if it is for a long time of tens of minutes to several hours, the oxidation becomes severe and the metal oxide becomes a thin foil. It may peel off from the nozzle, fly onto the quartz base material due to the flame, adhere as a foreign substance to the surface of the quartz base material, or may be mixed inside.

Therefore, the material of the nozzle from which oxygen, which is the combustion supporting gas, in the flame burner of the present invention blows out is thoroughly investigated, and as a result of repeated experiments, Ni or SUS310S, which is particularly excellent in heat resistance and oxidation resistance, is used. It was to be. Table 1 shows the compositions of Ni and these stainless steels.

[0023]

[Table 1]

The Ni or 310S nozzle 25 is composed of, for example, about 60 pipes having an outer diameter of 3 mm, an inner diameter of 1 mm and a length of 100 mm, and the root is brazed to a brass base. In the flame burner, the temperature of 800 ° C or higher is in the range of about 40 mm from the tip, and it is necessary that at least this portion is composed of Ni or 310S. However, almost no oxide was generated, and almost no foreign matter was attached to or mixed with the surface of the quartz base material W as foreign matter.

It is desirable that the outer case 24 of the flame burner 20 is also made of Ni material, but the temperature of this portion is less likely to rise than that of the nozzle, and since Ni is expensive, the material is expensive, such as SUS310S and SUS316L. It can also be made of stainless steel. Of course, the nozzle 25 and the outer case 24 are all made of Ni material or SUS310.
It goes without saying that it may be made of S.

The gas supply system to the nozzle may be divided into a plurality of parts so that the size of the flame in the flame burner can be changed. In order to heat a wide range, a large flame can be obtained by flowing gas from all the nozzles.

On the contrary, when squeezing and cutting the end of the quartz base material, it is necessary to heat a narrow range. At that time, the flame can be narrowed down by discharging the gas only from the central nozzle. Especially when the gas flow rate is reduced and used, the temperature of the nozzle tends to rise. In this case, it is effective to lower the nozzle temperature by mixing the combustible gas or the auxiliary combustion gas with an inert gas such as nitrogen or argon and increasing the flow velocity of the gas in the nozzle.

[0028]

EXAMPLES Next, examples and comparative examples of the present invention will be specifically described, but the present invention is not limited thereto. (Example 1) 3 mm outer diameter made of Ni material having a purity of 99%,
A pipe having an inner diameter of 1 mm was used as a nozzle of a flame burner, and was incorporated in an outer case made of SUS310S to produce a flame burner. This flame burner was set on a glass lathe, and an optical fiber preform made of synthetic quartz was stretched and flame-polished. An example of the conditions for the stretching process using this flame burner is shown below.

Oxygen gas was introduced into the nozzle of the flame burner.
Hydrogen gas was flowed through the gap between the outer case and the nozzle. The gas flow rates of the flame burner were adjusted to 250 SLM (standard liter / minute) for hydrogen and 130 SLM for oxygen. As shown in FIG. 2, while heating the preform with a flame, the flame burner was moved in a fixed direction at a speed of 15.0 mm / min, and at the same time, the chuck holding the end of the preform was moved by the column 2. It was moved in the direction opposite to the flame burner at a speed of 3 mm / min. Under the above conditions, a preform having an outer diameter of 65 mm and a length of 1,150 mm could be processed.

The preforms were processed at a rate of 5 pieces per day for 3 months, and the change with time of the number of foreign matters adhering to the surface of the preforms was investigated during the processing. Figure 3 shows the change in the number of foreign matter adhered per day. As is clear from FIG. 3, when the flame burner according to the present invention is used, almost no foreign matter adheres to the preform and no change with time occurs.

(Example 2) SUS310S was used as the nozzle material of the flame burner, and another glass lathe was used in Example 1
The preform was processed for 3 months in the same manner as above, and the transition of the number of foreign substances adhering to the surface of the preform was examined. The result is shown in FIG. As is clear from FIG. 4, SUS31
Even when 0S was used as the nozzle material, the amount of foreign matter attached to the preform was small.

(Comparative Example) SU is used as a flame burner nozzle material.
The number of foreign matters adhering to the surface of the preform for 3 months was examined under the same conditions as in Example 1 except that S304 and 316L were used. The result is shown in FIG. As is clear from FIG. 5, both 304 and 316L are generally used as a material having high corrosion resistance, but when used as a nozzle material of a flame burner, oxidation progresses in a relatively short period of time, resulting in oxide formation. A large amount of foreign matter adhered to the preform due to peeling. The amount of 304 generated was 2-3 times as large as that of 316L. Also, it can be seen that such a flame burner can be used only for about one month because the change over time is severe.

From the above, when Ni material or SUS310S is used as the material of the nozzle of the flame burner as in the present invention, metal oxide is produced even when the nozzle tip is exposed to a high temperature oxyhydrogen flame for a long time. The thin film hardly peels off and adheres to or mixes with the work piece, which can stabilize the operation and improve the quality throughout the processing period, improve the yield and productivity, and reduce the cost. Can be down.

The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, has substantially the same configuration as the technical idea described in the scope of the claims of the present invention, and has any similar effect to the present invention. It is included in the technical scope of the invention.

[0035]

As described in detail above, the material of the nozzle of the flame burner for glass processing is Ni or SUS310S.
When using, even if the nozzle tip is exposed to a high temperature oxyhydrogen flame for a long time, the metal oxide is generated and the thin film is peeled off, and it hardly adheres to or is mixed with the work piece.
It is possible to stabilize the operation and improve the quality throughout the processing period, improve the yield and productivity, and reduce the cost.

[Brief description of drawings]

FIG. 1 is a schematic view showing a configuration example of a flame burner for glass processing of the present invention. (A) The external view of a flame burner, (b) The jet nozzle front view which shows the front-end | tip part of a flame burner.

FIG. 2 is a schematic diagram showing a configuration example of a glass lathe.

FIG. 3 is a diagram showing the number of foreign matters generated per day with respect to the elapsed days of glass lathe operation when Ni is used as the nozzle material of the flame burner (Example 1).

FIG. 4 is a diagram showing the number of occurrences of foreign matter per day with respect to the elapsed days of glass lathe operation when the nozzle material of the flame burner is SUS310S (Example 2).

FIG. 5 is a diagram showing the number of foreign matters generated per day with respect to the elapsed days of glass lathe operation when the nozzle material of the flame burner is SUS304 or SUS316L (comparative example).

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Glass lathe, 2 ... Machine stand 3, 4 ... Column, 5 ... Chuck, 6 ... Moving stand, 20 ... Flame burner, 21 ... Hydrogen introduction pipe, 22 ... Oxygen introduction pipe, 23 ... Nozzle part, 24 ... Outside Case, 25 ... Nozzle, 26 ... Gap. W ... Quartz base material.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroyuki Koide               2-13-1, Isobe, Annaka-shi, Gunma Shinetsu               Chemical Industry Co., Ltd. Precision Materials Research Laboratory               Within (72) Inventor Tadakatsu Shimada               2-13-1, Isobe, Annaka-shi, Gunma Shinetsu               Chemical Industry Co., Ltd. Precision Materials Research Laboratory               Within (72) Inventor Hoshino               2-13-1, Isobe, Annaka-shi, Gunma Shinetsu               Chemical Industry Co., Ltd. Gunma Office (72) Inventor Hideo Hirasawa               2-13-1, Isobe, Annaka-shi, Gunma Shinetsu               Chemical Industry Co., Ltd. Precision Materials Research Laboratory               Within                (56) References JP-A-8-310823 (JP, A)                 JP-A-8-188441 (JP, A)                 JP-A-8-290921 (JP, A)                 JP-A-11-268921 (JP, A)                 Japanese Patent Publication 7-29795 (JP, B2)                 Actual public Sho 62-1543 (JP, Y2)

Claims (8)

(57) [Claims] 1. A flame burner used for processing a glass material, wherein the nozzle material of the flame burner is Ni or SU.
A flame burner for glass processing, which is S310S. 2. The flame burner for glass processing according to claim 1, wherein the glass material is synthetic quartz or natural quartz. 3. The flame burner for glass processing according to claim 1, wherein the glass material is an optical fiber preform. 4. The flame burner for glass processing according to any one of claims 1 to 3, wherein the combustible gas used in the flame burner is hydrogen. 5. The flame burner for glass processing according to any one of claims 1 to 4, wherein the combustion-assisting gas used in the flame burner is oxygen. 6. The flammable gas and the auxiliary gas used in the flame burner are mixed and burned at the tip of the flame burner.
A flame burner for glass processing according to item. 7. A glass lathe comprising the flame burner for glass processing according to any one of claims 1 to 6. 8. A synthetic quartz material set on a glass lathe,
A method for processing glass, characterized in that, when a natural quartz material or an optical fiber preform is processed by a flame burner, a flame burner manufactured by using Ni or SUS310S as a material of a nozzle of the burner is used.