CN116891337A - Large-caliber long cooling pipe for optical fiber drawing and use method - Google Patents
Large-caliber long cooling pipe for optical fiber drawing and use method Download PDFInfo
- Publication number
- CN116891337A CN116891337A CN202310946654.2A CN202310946654A CN116891337A CN 116891337 A CN116891337 A CN 116891337A CN 202310946654 A CN202310946654 A CN 202310946654A CN 116891337 A CN116891337 A CN 116891337A
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- China
- Prior art keywords
- cooling pipe
- cooling
- optical fiber
- cooling tube
- shutter
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- 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
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- 238000001816 cooling Methods 0.000 title claims abstract description 158
- 239000013307 optical fiber Substances 0.000 title claims abstract description 35
- 238000012681 fiber drawing Methods 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 10
- 239000001307 helium Substances 0.000 claims abstract description 43
- 229910052734 helium Inorganic materials 0.000 claims abstract description 43
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims abstract description 43
- 238000007789 sealing Methods 0.000 claims abstract description 17
- 239000007789 gas Substances 0.000 claims abstract description 16
- 238000004064 recycling Methods 0.000 claims abstract description 4
- 239000000498 cooling water Substances 0.000 claims description 15
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 238000004140 cleaning Methods 0.000 claims description 4
- 239000000835 fiber Substances 0.000 claims description 3
- 239000011261 inert gas Substances 0.000 claims description 3
- 238000005491 wire drawing Methods 0.000 claims description 3
- 238000011084 recovery Methods 0.000 abstract description 10
- 238000003754 machining Methods 0.000 abstract description 2
- 238000000605 extraction Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007380 fibre production Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 210000001503 joint Anatomy 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 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
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
- C03B37/027—Fibres composed of different sorts of glass, e.g. glass optical fibres
- C03B37/02718—Thermal treatment of the fibre during the drawing process, e.g. cooling
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Thermal 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)
- Light Guides In General And Applications Therefor (AREA)
Abstract
The invention provides a large-caliber long cooling pipe for optical fiber drawing and a use method thereof, wherein the large-caliber long cooling pipe comprises a plurality of cooling pipe bodies, the adjacent cooling pipe bodies are sequentially connected to form a long cooling pipe, two ends of the long cooling pipe are respectively connected with a cooling pipe end surface shutter, the long cooling pipe comprises a shutter body, a first radial channel and an end surface connecting part, the end surface connecting part is provided with a second radial channel, the first radial channel of one cooling pipe end surface shutter is connected with a cooling pipe helium inlet, and the second radial channel is connected with a recovered helium outlet; the first radial channel of the shutter of the end face of the other cooling pipe is connected with the air sealing inlet of the cooling pipe, and the second radial channel is connected with the recycling helium outlet. The invention reduces the machining and mounting precision of the cooling pipe; helium recovery ports are respectively arranged at the two shutters, so that negative pressure is formed to improve the leakage of the end face of the large-caliber cooling pipe; the shutter is provided with an air seal, and the overflow of helium in the cooling pipe is reduced by introducing positive pressure formed by shielding gas, so that the helium is saved, and the recovery efficiency of the helium is improved.
Description
Technical Field
The invention belongs to the field of optical fiber production, and particularly relates to a large-caliber long cooling pipe for optical fiber drawing and a use method thereof.
Background
The optical fiber is produced by high temperature melting of the preform rod in an optical fiber drawing furnace, drawing to form a wire, cooling, coating, solidifying and other processes. The optical fiber cooling is completed in a cooling pipe, and the working principle is that a refrigerator cools the cooling pipe, and rare gas helium is introduced into the cooling pipe as a heat exchange medium to cool the optical fiber.
The rise in the price of helium, subject to the supply of helium, increases the manufacturing cost of the optical fiber. In order to reduce helium consumption, a cooling pipe is generally made into a small hole structure with an inner hole of about 5-8mm in industry, and is made into an opening and closing mode so as to solve the requirements of cleaning the wall of the cooling pipe and producing and feeding wires. The cooling pipe with small aperture has complex structure, high cost and difficult installation, extension or change of structure in order to meet the precision requirement in the length direction. In addition, the structure has higher sealing requirement, the sections are required to be excessively connected, and the problem of helium leakage cannot be completely solved in the long-dimension direction.
Disclosure of Invention
The invention aims to provide a large-caliber long cooling pipe for optical fiber drawing, which not only can reduce the machining and mounting precision of the cooling pipe, but also can effectively solve the problem of helium leakage, and a use method thereof.
The invention is realized in the following way:
the large-caliber long cooling pipe for optical fiber drawing is characterized by comprising a plurality of cooling pipe bodies, wherein the adjacent cooling pipe bodies are sequentially connected to form a long cooling pipe, a cooling water channel is arranged on the long cooling pipe, an insulating layer is arranged on the periphery of the long cooling pipe, two ends of the cooling pipe are respectively connected with a cooling pipe end face shutter, the cooling pipe end face shutter is of a reducing structure and comprises a shutter body, a small-caliber optical fiber channel pipe body communicated with the long cooling pipe, a first radial channel and an end face connecting part used for being connected with one end part of the long cooling pipe are arranged on the shutter body, the inner end of the shutter body stretches into the long cooling pipe for a set distance, a second radial channel is arranged on the end face connecting part, the first radial channel of one cooling pipe end face shutter is connected with a cooling pipe helium inlet, and the second radial channel is connected with a recovered helium outlet; the first radial channel of the shutter of the end face of the other cooling pipe is connected with the air sealing inlet of the cooling pipe, and the second radial channel is connected with the recycling helium outlet.
In some alternative embodiments, an extension section is disposed between the end surface connection portion and the shutter body, an annular space is disposed between the extension section and the outer surface of the small-caliber optical fiber channel tube, and the second radial channel is disposed at the extension section.
In some alternative embodiments, adjacent cooling tubes are sealingly connected by end flanges.
In some alternative embodiments, a seal groove for mounting a seal is provided on the end face of the cooling tube body.
In some alternative embodiments, a plurality of axial cooling water passages are provided in the cooling tube body, the axial cooling water passages in adjacent cooling tubes being in communication.
In some alternative embodiments, the long cooling tube has an inner diameter greater than 30mm.
In some alternative embodiments, the inner end of the shutter body extends 50-150mm into the long cooling tube.
In some alternative embodiments, the inert gas is introduced at the cooling tube gas seal inlet.
In some alternative embodiments, the small bore fibre channel tube has an inner diameter of 5-8mm.
The method for using the large-caliber long cooling pipe for optical fiber drawing is characterized in that: the method comprises the following steps:
before the production of the wire drawing tower, opening the shutters at the end surfaces of the two cooling pipes, cleaning the inner walls of the cooling pipes, and recovering the production; after the two cooling tube end face shutters are closed, cooling helium is introduced into the first radial channel of one cooling tube end face shutter, shielding gas is introduced into the first radial channel of the other sealing cooling tube end face shutter for sealing, and the overflow of helium in the cooling tube is reduced by positive pressure formed by introducing the shielding gas. After helium recovery is respectively communicated with the second radial channels of the two cooling tube end face shutters, negative pressure is formed to improve the leakage of the large-caliber cooling tube end face; during operation, low-temperature cooling water is introduced into the inner wall of the cooling pipe for heat exchange.
The beneficial effects of the invention are as follows:
1. the invention adopts the large-caliber cooling pipe, and shutters with the inner diameter of 5mm are arranged at the outlets of the two ends of the cooling pipe and used for sealing the cooling pipe, and the cooling pipe can be taken down during shutdown, thereby reducing the processing and mounting precision of the cooling pipe; helium recovery ports are respectively arranged at the two shutters, so that negative pressure is formed to improve the leakage of the end face of the large-caliber cooling pipe; the shutter is provided with an air seal, and positive pressure formed by introducing protective gas reduces the overflow of helium in the cooling pipe, so that the helium is saved and the recovery efficiency of the helium is improved;
2. the second radial channel (helium recovery port) is arranged at the extension section, namely, the extraction port of the helium recovery port is positioned in the cooling pipe, the extraction position avoids the optical fiber channel, the optical fiber jitter is reduced, and the extraction efficiency is further improved;
3. the upper and lower openings of the cooling tube are provided with small holes through shutters, so that the helium leakage problem is effectively avoided; the shutters of the upper and lower openings adopt the same structure and are respectively used for air intake, helium recovery and air sealing, thus having strong universality
4. The long cooling pipe adopts a butt joint mode, the outer wall is wrapped by using a heat insulation material, and the problem of condensation can be avoided by using low-temperature water for cooling.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic structural diagram of a large-caliber long cooling tube for optical fiber drawing according to an embodiment of the present invention.
Fig. 2 is a cross-sectional view of a shutter for cooling tube end surfaces according to an embodiment of the present invention.
Fig. 3 is a schematic cross-sectional view of a cooling pipe body according to an embodiment of the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the present invention, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or those that are conventionally put in use of the product of the application, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific direction, be configured and operated in a specific direction, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal," "vertical," "overhang," and the like do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.
The features and capabilities of the present invention are described in further detail below in connection with the examples.
As shown in fig. 1, this embodiment provides a large-caliber long cooling tube for optical fiber drawing, which comprises a plurality of cooling tube bodies 5, wherein cooling water channels 11 are arranged on the cooling tube bodies 5, adjacent cooling tube bodies are sequentially connected to form a long cooling tube, an insulating layer 4 is arranged on the periphery of the long cooling tube, and two ends of the insulating layer are respectively connected with end face shutters (1, 10) of the cooling tube.
As shown in fig. 2, the shutter at the end face of the cooling tube has a variable diameter structure, which comprises a shutter body 101, wherein the shutter body 101 is provided with a small-caliber optical fiber channel tube body 102 communicated with the long cooling tube, a first radial channel 2 and an end face connecting part 104 connected with one end of the long cooling tube, and the inner end of the shutter body extends into the long cooling tube for a set distance. An extension section 103 is arranged between the end face connecting part 104 and the shutter body 101, an annular space 105 is arranged between the extension section 103 and the outside of the small-caliber optical fiber channel body, a second radial channel is arranged at the extension section, and the second radial channel is communicated with the annular space. The first radial channel 2 of the shutter 1 of one cooling tube end face is connected with a cooling tube helium inlet, and the second radial channel 3 is connected with a recovered helium outlet; the first radial channel 9 of the shutter of the end face of the other cooling pipe is connected with the gas seal inlet of the cooling pipe, and the second radial channel 8 is connected with the outlet of the recovered helium gas.
In the embodiment, the length of the long cooling pipe body is 9-10m, and the inner diameter is larger than 30mm. Shutters with the inner diameter of 5mm are arranged at the outlets of the two ends of the long cooling pipe and used for sealing the cooling pipe, and the shutters can be taken down during shutdown. That is, the inner diameter of the small-caliber fiber channel tube body of the cooling tube end face shutter is 5mm. The end face flange is used for being in sealing connection with the adjacent two cooling pipe bodies, free splicing and extension are achieved, a better cooling effect is achieved, and a sealing groove for installing a sealing piece is formed in the end face of each cooling pipe body, so that the adjacent two cooling pipe bodies can be in sealing connection, and cooling water and helium are prevented from overflowing. The cooling pipe is a seamless steel pipe with a sandwich cooling water channel, is not only used for cooling the optical fiber, but also can effectively solve the helium leakage problem. Specifically, as shown in fig. 3, a plurality of axial cooling water passages 5 are provided in the cooling pipe body, the axial cooling water passages in the adjacent cooling pipes are communicated, and an interface (omitted in the figure) connected to the cooling water pump is provided in the cooling pipe body.
The embodiment also provides a use method of the large-caliber long cooling pipe for optical fiber drawing, which specifically comprises the following steps:
before the production of the wire drawing tower, opening the shutters (1, 10) on the end surfaces of the two cooling pipes, cleaning the inner walls of the cooling pipes, and recovering the production; after the two cooling pipe end face shutters (1, 10) are closed, cooling helium is introduced into the first radial channel 2 of the cooling pipe end face shutter 1, shielding gas (inert gas) is introduced into the first radial channel 9 of the sealing cooling pipe end face shutter 10 for sealing, and the overflow of helium in the cooling pipe is reduced by positive pressure formed by introducing the shielding gas. The second radial channels (3, 8) of the shutters at the end surfaces of the two cooling pipes are respectively communicated with helium gas for recovery, so that negative pressure is formed to improve the end surface leakage of the large-caliber cooling pipe; during operation, low-temperature cooling water is introduced into the inner wall of the cooling pipe for heat exchange. In the whole production process, helium leakage and overflow are less, and the cooling pipe can be cooled efficiently by the additional helium recovery device.
The embodiments described above are some, but not all embodiments of the invention. The detailed description of the embodiments of the invention is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Claims (10)
1. The large-caliber long cooling pipe for optical fiber drawing is characterized by comprising a plurality of cooling pipe bodies, wherein cooling water channels are formed in the cooling pipe bodies, the adjacent cooling pipe bodies are sequentially connected to form a long cooling pipe, an insulating layer is arranged on the periphery of the long cooling pipe, two ends of the cooling pipe are respectively connected with a cooling pipe end face shutter, the cooling pipe end face shutter is of a reducing structure and comprises a shutter body, a small-caliber optical fiber channel pipe body communicated with the long cooling pipe, a first radial channel and an end face connecting part used for being connected with one end part of the long cooling pipe are arranged on the shutter body, the inner end of the shutter body stretches into the long cooling pipe for a set distance, a second radial channel is formed in the end face connecting part, the first radial channel of one cooling pipe end face shutter is connected with a cooling pipe helium inlet, and the second radial channel is connected with a recovered helium outlet; the first radial channel of the shutter of the end face of the other cooling pipe is connected with the air sealing inlet of the cooling pipe, and the second radial channel is connected with the recycling helium outlet.
2. The large-caliber long cooling tube for optical fiber drawing according to claim 1, wherein an extension section is arranged between the end surface connecting part and the shutter body, an annular space is arranged between the extension section and the outer diameter of the small-caliber optical fiber channel tube body, and the second radial channel is arranged at the extension section.
3. A large diameter long cooling tube for optical fiber drawing according to claim 1 or 2, wherein adjacent cooling tube bodies are connected by end flange seal.
4. A large-diameter long cooling tube for optical fiber drawing according to claim 3, wherein a seal groove for mounting a seal is provided on an end face of the cooling tube body.
5. A large-diameter long cooling tube for optical fiber drawing according to claim 1 or 2, wherein a plurality of axial cooling water passages are provided on the cooling tube body, and the axial cooling water passages on the adjacent cooling tubes are communicated.
6. A large diameter long cooling tube for optical fiber drawing according to claim 1 or 2, wherein the inner diameter of the long cooling tube body is larger than 30mm.
7. A large diameter long cooling tube for optical fiber drawing according to claim 1 or 2, wherein the inner end of the shutter body extends into the long cooling tube by 50-150mm.
8. A large diameter long cooling tube for optical fiber drawing according to claim 1 or 2, wherein inert gas is introduced into the air seal inlet of the cooling tube.
9. A large diameter long cooling tube for optical fiber drawing according to claim 1 or 2, wherein the inner diameter of the small diameter fiber passage tube body is 5-8mm.
10. A method of using the large diameter long cooling tube for optical fiber drawing according to any one of claims 1 to 9, wherein:
before the production of the wire drawing tower, opening the shutters at the end surfaces of the two cooling pipes, cleaning the inner walls of the cooling pipes, and recovering the production; after the two cooling tube end face shutters are closed, cooling helium gas is introduced into a first radial channel of one cooling tube end face shutter, shielding gas is introduced into a first radial channel of the other sealing cooling tube end face shutter for sealing, the overflow of helium gas in the cooling tube is reduced by positive pressure formed by introducing the shielding gas, and after helium gas is respectively communicated with a second radial channel of the two cooling tube end face shutters for recycling, negative pressure is formed to improve the end face leakage of the large-caliber cooling tube; during operation, low-temperature cooling water is introduced into the inner wall of the cooling pipe for heat exchange.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310946654.2A CN116891337A (en) | 2023-07-28 | 2023-07-28 | Large-caliber long cooling pipe for optical fiber drawing and use method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310946654.2A CN116891337A (en) | 2023-07-28 | 2023-07-28 | Large-caliber long cooling pipe for optical fiber drawing and use method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116891337A true CN116891337A (en) | 2023-10-17 |
Family
ID=88313458
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310946654.2A Pending CN116891337A (en) | 2023-07-28 | 2023-07-28 | Large-caliber long cooling pipe for optical fiber drawing and use method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116891337A (en) |
-
2023
- 2023-07-28 CN CN202310946654.2A patent/CN116891337A/en active Pending
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