CN109264985B - Degassing method and device for optical fiber preform - Google Patents
Degassing method and device for optical fiber preform Download PDFInfo
- Publication number
- CN109264985B CN109264985B CN201811353111.5A CN201811353111A CN109264985B CN 109264985 B CN109264985 B CN 109264985B CN 201811353111 A CN201811353111 A CN 201811353111A CN 109264985 B CN109264985 B CN 109264985B
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- furnace
- fiber preform
- vacuum furnace
- temperature
- 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.)
- Active
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 61
- 238000007872 degassing Methods 0.000 title claims abstract description 36
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 45
- 238000010438 heat treatment Methods 0.000 claims abstract description 35
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 31
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 31
- 239000010439 graphite Substances 0.000 claims abstract description 31
- 238000001816 cooling Methods 0.000 claims description 39
- 230000006835 compression Effects 0.000 claims description 38
- 238000007906 compression Methods 0.000 claims description 38
- 238000009413 insulation Methods 0.000 claims description 32
- 239000010453 quartz Substances 0.000 claims description 24
- -1 polytetrafluoroethylene Polymers 0.000 claims description 13
- 239000002184 metal Substances 0.000 claims description 12
- 238000004321 preservation Methods 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 7
- 238000007789 sealing Methods 0.000 claims description 6
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 5
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 5
- 238000012544 monitoring process Methods 0.000 claims description 3
- 230000000630 rising effect Effects 0.000 claims 1
- 238000000137 annealing Methods 0.000 abstract description 8
- 239000012535 impurity Substances 0.000 abstract description 3
- 238000012423 maintenance Methods 0.000 abstract description 2
- 230000002035 prolonged effect Effects 0.000 abstract description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 23
- 238000004519 manufacturing process Methods 0.000 description 8
- 239000007789 gas Substances 0.000 description 7
- 230000035882 stress Effects 0.000 description 7
- 239000011521 glass Substances 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 229910052681 coesite Inorganic materials 0.000 description 2
- 229910052906 cristobalite Inorganic materials 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 229910052682 stishovite Inorganic materials 0.000 description 2
- 229910052905 tridymite Inorganic materials 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005906 dihydroxylation reaction Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012681 fiber drawing Methods 0.000 description 1
- 229920001973 fluoroelastomer Polymers 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 230000008646 thermal stress Effects 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]
- C03B37/018—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] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
- C03B37/01853—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
- Y02P40/57—Improving the yield, e-g- reduction of reject rates
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Thermal 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)
Abstract
The embodiment of the application discloses a degassing method and a degassing device for an optical fiber preform. Furthermore, the present application provides an apparatus for applying the above-mentioned optical fiber preform degassing method. The embodiment of the application provides a degassing method and a degassing device for an optical fiber preform, wherein a vacuum furnace is adopted to provide a heat source, a heating body is composed of a plurality of sections of graphite heating pipes, and meanwhile, a graphite equalizing pipe is arranged in the vacuum furnace and is provided with a plurality of groups of temperature sensors, so that the temperature in the furnace is controlled, and the vacuum state is kept in the furnace all the time, so that the service life of the furnace body is greatly prolonged, and the maintenance cost is reduced. In addition, the degassing and annealing of the optical fiber preform are completed in the quartz glass tube, and the quartz glass tube is close to a vacuum state, so that the movable impurities in the furnace are less, and the surface pollution of the optical fiber preform can be greatly reduced.
Description
Technical Field
The application relates to the technical field of optical fiber preforms, in particular to a degassing method and device for an optical fiber preform.
Background
Since quartz optical fiber is invented and is largely applied to the communication field, market demand is increased year by year, the whole optical fiber market is up to trillion scale at present, various manufacturers continuously expand production, lower production cost and higher product quality are continuously pursued.
The main production links in the optical fiber preform production process are core rod production and overclad production, both contain the deposition of SiO2 dust, then sinter into glass, and in the sintering process, a certain amount of gas such as helium, nitrogen, chlorine and the like remains in the glass body, and a large amount of internal stress remains. The existence of residual gas and internal stress can seriously affect the drawing quality of the optical fiber, including increasing the fiber breakage probability in the optical fiber drawing process, reducing the strength of the optical fiber, increasing the attenuation value of the optical fiber and the like, and the degassing and annealing of the core rod and the optical fiber preform can well solve the problems.
Theoretically, annealing of the optical fiber preform is completed at about 1100 ℃ for several hours, and gas molecules inside the glass body are emitted to the surface through thermal motion; the atomic structure of the internal SiO2 is also thermally moved at high temperature to be rearranged, thereby releasing the internal stress. Patent CN 106830651a discloses a method and a device for dehydroxylation annealing of large-size optical fiber preforms, in which a plurality of optical fiber preforms are transversely placed in a furnace chamber, and internal stress and residual gas in the rods are eliminated through certain steps of heating, heat preservation and cooling. However, the optical fiber preform rod generates new internal stress in the radial direction due to the gravity action at high temperature due to the transverse placement; the outer surface of the optical fiber preform is exposed in the heat preservation furnace, and as the heating body and the heat preservation fiber are exposed outside, a large amount of volatilized metal impurities in the cavity are bonded to the surface of the preform to cause pollution, so that the quality of the preform is affected. Patent CN105753311a discloses a degassing device and a degassing method for optical fiber preforms, wherein a plurality of optical fiber preforms are placed in a quartz tube, the quartz tube is vacuumized, and degassing is performed after the temperature is raised, so that the production efficiency is improved. However, the device has high sealing requirements, especially the rod size of the optical fiber preform is difficult to precisely control, and the sealing of the quartz tube and the quartz plate is difficult. The temperature of the plurality of prefabricated rods in the radial direction of the prefabricated rods is uneven in the same quartz furnace, partial residual stress exists after degassing is finished, and new thermal stress is generated.
The degassing and annealing conditions of the optical fiber preform are very severe, if the temperature is too low, the internal gas cannot be separated, and if the temperature is lower than the specific temperature of 950 ℃, the degassing and annealing functions cannot be completed for a long time; if the temperature is too high and exceeds 1200 ℃ or even higher, the surface of the optical fiber preform rod can be gradually crystallized and embrittled, and the drawing quality of the optical fiber is seriously affected. Thus, a moderate degassing annealing process is defined, which is critical for the production of optical fiber preforms.
Disclosure of Invention
The embodiment of the application aims to provide a degassing method and device for an optical fiber preform, wherein the whole degassing process is performed under vacuum, and residual gas of the optical fiber preform can rapidly leave the surface of the preform through thermal motion, so that the rapid degassing work is facilitated.
To achieve the above object, an embodiment of the present application provides a degassing method for an optical fiber preform, including the steps of:
step one, raising the internal temperature of a quartz glass tube of a vacuum furnace to 600-900 ℃;
opening a furnace door of the cooling chamber, mounting the optical fiber preform on a quartz hanging rod, descending a hanging compression rod until the O-shaped ring is sealed, and closing the furnace door;
and thirdly, vacuumizing the cooling chamber by using a vacuumizing device, heating to 1000-1300 ℃ at the speed of 10-300 ℃/hour, keeping for 3-20 hours, cooling to below 900 ℃ at the speed of 10-300 ℃/hour, keeping for 0.5-3 hours, and then lifting the hanging compression bar, wherein the optical fiber preform is cooled in the cooling chamber.
In some embodiments, the temperature rise rate is less than or equal to 200 ℃/h when the degassing temperature is raised, and the temperature drop rate is less than or equal to 200 ℃/h when the cooling temperature is lowered.
In some embodiments, the absolute pressure inside the vacuum furnace is controlled to be 5-100 Pa, and the absolute pressure of the cooling chamber is controlled to be 10-200 Pa during operation.
In addition, the application provides a device applied to the optical fiber preform degassing method, which comprises a vacuum furnace, a cooling chamber and a hanging compression bar, wherein the cooling chamber is arranged at the top of the vacuum furnace, a heat insulation layer is arranged between the vacuum furnace and the cooling chamber, the hanging compression bar sequentially passes through the cooling chamber and the heat insulation layer to enter the vacuum furnace, the bottom end of the hanging compression bar is provided with the optical fiber preform, and the vacuum furnace and the cooling chamber are respectively provided with a vacuumizing device.
In some embodiments, the insulating layer includes a quartz insulating sheet and a graphite insulating sheet disposed over the quartz insulating sheet.
In some embodiments, the vacuum furnace comprises a furnace shell, a heating body, a graphite uniform heating pipe, a heat preservation felt and a quartz glass pipe which is arranged in the furnace shell and can contain an optical fiber preform rod, wherein the heat preservation felt, the heating body and the graphite uniform heating pipe are sequentially arranged from the furnace shell to the quartz glass pipe.
In some embodiments, the heating body in the vacuum furnace consists of 2-6 groups of heaters, the gap between the adjacent heaters is 20-50 mm, and each group of heating body is provided with two temperature sensors, one temperature sensor is used for monitoring the temperature, and the other temperature sensor is used for controlling the temperature.
In some embodiments, the graphite equalizing tube is formed by splicing 2-6 groups of graphite tubes, and the thickness of the graphite tubes is 4-8 mm.
In some embodiments, the top of the heat insulating layer is provided with a metal compression ring, and a screw sequentially penetrates through the metal compression ring and the top of the vacuum furnace to realize the fixed connection of the heat insulating layer and the vacuum furnace.
In some embodiments, a polytetrafluoroethylene pad is arranged between the heat insulation layer and the metal compression ring, a perfluoro O-shaped ring is arranged between the heat insulation layer and the vacuum furnace, the cross section diameter of the perfluoro O-shaped ring is 6-12 mm, and the sealing compression amount is 1/4-1/2 of the cross section diameter.
Compared with the prior art, the embodiment of the application has the advantages that: the embodiment of the application provides a degassing method and a degassing device for an optical fiber preform, wherein a vacuum furnace is adopted to provide a heat source, a heating body is composed of a plurality of sections of graphite heating pipes, and meanwhile, a graphite equalizing pipe is arranged in the vacuum furnace and is provided with a plurality of groups of temperature sensors, so that the temperature in the furnace is controlled, and the vacuum state is kept in the furnace all the time, so that the service life of the furnace body is greatly prolonged, and the maintenance cost is reduced. In addition, the degassing and annealing of the optical fiber preform are completed in the quartz glass tube, and the quartz glass tube is in a vacuum state, so that the movable impurities in the furnace are less, and the surface pollution of the optical fiber preform can be greatly reduced; in the vacuum environment, the residual gas in the preform is also beneficial to outward diffusion, and the degassing time and the temperature are greatly reduced. And meanwhile, the optical fiber preform rod is vertically downward during degassing, so that the release of the internal stress of the upper is facilitated, and the optical fiber with higher qualification rate is pulled out.
Drawings
FIG. 1 is a schematic diagram of an apparatus according to an exemplary embodiment of the present application;
FIG. 2 is a schematic view showing a structure of a vacuum furnace according to an exemplary embodiment of the present application;
reference numerals illustrate: 1. a vacuum furnace; 2. a cooling chamber; 3. a furnace door; 4. hanging a compression bar; 5. a vacuum pumping device; 6. an O-ring; 7. an optical fiber preform; 8. a graphite heat insulating sheet; 9. quartz heat-insulating sheet; 10. a quartz hanging rod; 101. a quartz glass tube; 102. a heating body; 103. a graphite equalizing tube; 104. a thermal insulation felt; 105. a furnace shell; 106. a perfluoro O-ring; 107. a polytetrafluoroethylene pad; 108. metal compression rings, 109, screws.
Detailed Description
Further advantages and effects of the present application will become apparent to those skilled in the art from the disclosure of the present application, which is described by the following specific examples.
The embodiment discloses a degassing method of an optical fiber preform, comprising the following steps:
step one, raising the internal temperature of a quartz glass tube of a vacuum furnace to 600-900 ℃;
opening a furnace door of the cooling chamber, mounting the optical fiber preform on a quartz hanging rod, descending a hanging compression rod until the O-shaped ring is sealed, and closing the furnace door;
and thirdly, vacuumizing the cooling chamber by using a vacuumizing device, heating to 1000-1300 ℃ at the speed of 10-300 ℃/hour, keeping for 3-20 hours, cooling to below 900 ℃ at the speed of 10-300 ℃/hour, keeping for 0.5-3 hours, and then lifting the hanging compression bar, wherein the optical fiber preform is cooled in the cooling chamber.
Further, when the degassing temperature is raised, the temperature raising speed is less than or equal to 200 ℃/h, and when the temperature is lowered, the temperature lowering speed is less than or equal to 200 ℃/h. The absolute pressure in the vacuum furnace is controlled to be 5-100 Pa, and the absolute pressure in the cooling chamber is controlled to be 10-200 Pa in the operation process.
In addition, the application provides a device applied to the optical fiber preform degassing method, which comprises a vacuum furnace, a cooling chamber and a hanging compression bar, wherein the cooling chamber is arranged at the top of the vacuum furnace, a heat insulation layer is arranged between the vacuum furnace and the cooling chamber, the hanging compression bar sequentially passes through the cooling chamber and the heat insulation layer to enter the vacuum furnace, the bottom end of the hanging compression bar is provided with the optical fiber preform, and the vacuum furnace and the cooling chamber are respectively provided with a vacuumizing device.
Further, the heat insulation layer comprises a quartz heat insulation sheet and a graphite heat insulation sheet arranged above the quartz heat insulation sheet.
Further, the vacuum furnace comprises a furnace shell, a heating body, a graphite uniform heating pipe, a heat preservation felt and a quartz glass pipe which is arranged in the furnace shell and can accommodate the optical fiber preform, and the heat preservation felt, the heating body and the graphite uniform heating pipe are sequentially arranged in the direction from the furnace shell to the quartz glass pipe.
Furthermore, the heating body in the vacuum furnace consists of 2-6 groups of heaters, the gap between the adjacent heaters is 20-50 mm, two temperature sensors are arranged on each group of heating body, one temperature sensor is used for monitoring the temperature, and the other temperature sensor is used for controlling the temperature.
Further, the graphite equalizing pipe is formed by splicing 2-6 groups of graphite pipes, and the thickness of the graphite pipes is 4-8 mm.
Further, the top of the heat insulation layer is provided with a metal compression ring, and a screw sequentially penetrates through the metal compression ring and the top of the vacuum furnace to realize the fixed connection of the heat insulation layer and the vacuum furnace.
Further, a polytetrafluoroethylene pad is arranged between the heat insulation layer and the metal compression ring, a perfluoro O-shaped ring is arranged between the heat insulation layer and the vacuum furnace, the section diameter of the perfluoro O-shaped ring is 6-12 mm, and the sealing compression amount is 1/4-1/2 of the section diameter.
The present application will be described in detail with reference to specific examples.
The device of the optical fiber preform degassing furnace shown in the figure 1 comprises a vacuum furnace 1, a cooling chamber 2, a furnace door 3, a hanging compression bar 4, a vacuumizing device 5, an O-shaped ring 6, a graphite heat insulation sheet 8, a quartz heat insulation sheet 9 and a quartz hanging bar 10.
The vacuum furnace shown in fig. 2 comprises a quartz glass tube 101, a heating body 102, a graphite equalizing tube 103, a heat insulation felt 104, a furnace shell 105, a perfluoro O-ring 106, a polytetrafluoroethylene pad 107, a metal compression ring 108 and screws 109.
The target degassing object is an optical fiber preform, the diameter of which is less than or equal to 180mm, and the qualified length of which is less than or equal to 2500mm; the length of the quartz glass tube 101 is 4000mm, the inner diameter is 260mm, the thickness is 5mm, the thickness of the top flange is 10mm, and the outer diameter of the flange is 500mm; the graphite equalizing pipe 103 is formed by splicing 5 sections of graphite pipes, the inner diameter of the equalizing pipe is 290mm, the outer diameter of the equalizing pipe is 302mm, and the total height of the equalizing pipe after splicing is 3600mm; the heating body 102 consists of 5 groups of cylindrical graphite heating bodies, the height of a single heating body is 600mm, the inner diameter is 360mm, the distance between two heating body pieces is 650mm, and the total height of the heating body 102 is 3200mm; the thickness of the heat insulation felt 104 is 120mm, the heat insulation felt is distributed around a hearth, the outer diameter of the hearth is 920mm, and the total height is 4300mm; the thickness of the quartz heat insulation sheet 11 is 10mm, the outer diameter is 300mm, and the inner hole is 50mm; the graphite heat insulation sheet has the outer diameter of 300mm, the thickness of 20mm, the inner diameter of 60mm and is made of graphite felt.
The height of the inner cavity of the cooling chamber 2 is 5000mm, and the diameter is 800mm; the diameter of the hanging compression bar is 50mm, the length below the flange is 4800mm, the material is SUS 316L, and the surface is polished; the length of the quartz hanging rod is 800mm, the diameter of the quartz hanging rod is 45mm, and the upper end of the quartz hanging rod is connected with the hanging compression rod through a pin hole; the O-shaped ring 6 is made of fluororubber material, the diameter is 8mm, and the seal pressing amount is set to be 3mm.
After the furnace body is installed, the furnace body 1 is vacuumized by utilizing the vacuumizing device 5, when the absolute pressure is 10Pa, the valve is closed, the furnace chamber is subjected to pressure maintaining test, the pressure is maintained for 48 hours, the pressure change condition is checked, and if the pressure is greatly increased, the leakage point is checked. Under the no-load state, the furnace door 3 is closed, the hanging compression rod is lowered until the compression amount of the O-shaped ring 6 reaches about 3mm, the stroke position S of the hanging compression rod is recorded, the furnace door 3 is closed, the cooling chamber 2 is vacuumized by the vacuumizing device 5, when the absolute pressure is 10Pa, the valve is closed, the pressure maintaining test is carried out on the furnace chamber, the pressure maintaining is carried out for 48 hours, the pressure change condition is checked, and if the pressure is greatly increased, the leakage point is checked. After the sealing test of the vacuum furnace and the cooling chamber is carried out, equipment debugging is carried out, N2 is filled into the vacuum furnace, vacuumizing is carried out again, and when the pressure is displayed as 50Pa, the valve is closed, and the negative pressure value in the furnace is maintained. The heating body 102 is electrified and heated, the axial temperature of the center of the quartz glass tube is measured by using an external temperature thermocouple, the upper end position of the heating body 102 is measured, the total length is 3200mm, the interval is 50mm, one point is taken, the temperature values of 65 points are recorded, the temperature fluctuation value of 56 points in the middle is checked, the temperature is controlled by each temperature measuring sensor corresponding to the heating body 102 until the temperature fluctuation value of 56 points is 1100+/-5 ℃, the temperature is kept for 48 hours, and then the temperature is reduced to 700 ℃. The furnace door 3 is opened, an optical fiber preform with the diameter of 160mm and the effective length of 2500mm is mounted at the lower end of the quartz hanging rod 10, the hanging compression rod 4 is lowered to a position S, the furnace door is closed, the vacuumizing device is opened until the absolute pressure value in the cooling chamber reaches 50Pa, and the valve is closed. Waiting for 1 hour, then raising the temperature to 1200 ℃ at the speed of 50 ℃/hour, keeping for 6 hours, lowering the temperature to 700 ℃ at the speed of 50 ℃/hour, keeping for 2 hours, raising the hanging compression bar 4200mm, keeping for 2 hours, opening the furnace door, and taking out the optical fiber preform. The preform is drawn into an optical fiber, and an optical fiber with low attenuation and high strength can be obtained.
While the application has been described in detail in the foregoing general description and specific examples, it will be apparent to those skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the application and are intended to be within the scope of the application as claimed.
Claims (5)
1. A method for degassing an optical fiber preform, comprising the steps of:
step one, raising the internal temperature of a quartz glass tube of a vacuum furnace to 600-900 ℃;
opening a furnace door of the cooling chamber, mounting the optical fiber preform on a quartz hanging rod, descending a hanging compression rod until the O-shaped ring is sealed, and closing the furnace door;
step three, vacuumizing the cooling chamber by using a vacuumizing device, heating to 1000-1300 ℃ at the speed of 10-300 ℃/hour, keeping for 3-20 hours, cooling to below 900 ℃ at the speed of 10-300 ℃/hour, keeping for 0.5-3 hours, then lifting a hanging compression bar, and cooling the optical fiber preform in the cooling chamber;
when the degassing temperature rises, the temperature rising speed is less than or equal to 200 ℃/h, and when the temperature is reduced, the temperature reducing speed is less than or equal to 200 ℃/h;
the absolute pressure in the vacuum furnace is controlled to be 5-100 Pa, and the absolute pressure in the cooling chamber is controlled to be 10-200 Pa in the operation process.
2. An apparatus for applying the degassing method of an optical fiber preform according to claim 1, characterized in that: the device comprises a vacuum furnace, a cooling chamber and a hanging compression bar, wherein the cooling chamber is arranged at the top of the vacuum furnace, a heat insulation layer is arranged between the vacuum furnace and the cooling chamber, the hanging compression bar sequentially penetrates through the cooling chamber and the heat insulation layer to enter the vacuum furnace, an optical fiber preform is arranged at the bottom end of the hanging compression bar, and vacuumizing devices are respectively arranged on the vacuum furnace and the cooling chamber;
the heat insulation layer comprises a quartz heat insulation sheet and a graphite heat insulation sheet arranged above the quartz heat insulation sheet;
the vacuum furnace comprises a furnace shell, a heating body, a graphite uniform heat pipe, a heat preservation felt and a quartz glass pipe which is arranged in the furnace shell and can accommodate an optical fiber preform, wherein the heat preservation felt, the heating body and the graphite uniform heat pipe are sequentially arranged in the direction from the furnace shell to the quartz glass pipe;
the heating body in the vacuum furnace consists of 2-6 groups of heaters, the gap between the adjacent heaters is 20-50 mm, two temperature sensors are arranged on each group of heating body, one temperature sensor is used for monitoring the temperature, and the other temperature sensor is used for controlling the temperature.
3. The apparatus according to claim 2, wherein: the graphite equalizing pipe is formed by splicing 2-6 groups of graphite pipes, and the thickness of each graphite pipe is 4-8 mm.
4. The apparatus according to claim 2, wherein: the top of the heat insulation layer is provided with a metal compression ring, and a screw sequentially penetrates through the metal compression ring and the top of the vacuum furnace to realize the fixed connection of the heat insulation layer and the vacuum furnace.
5. The apparatus according to claim 2, wherein: a polytetrafluoroethylene pad is arranged between the heat insulation layer and the metal compression ring, a perfluoro O-shaped ring is arranged between the heat insulation layer and the vacuum furnace, the section diameter of the perfluoro O-shaped ring is 6-12 mm, and the sealing compression amount is 1/4-1/2 of the section diameter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811353111.5A CN109264985B (en) | 2018-11-14 | 2018-11-14 | Degassing method and device for optical fiber preform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811353111.5A CN109264985B (en) | 2018-11-14 | 2018-11-14 | Degassing method and device for optical fiber preform |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109264985A CN109264985A (en) | 2019-01-25 |
| CN109264985B true CN109264985B (en) | 2023-09-22 |
Family
ID=65188921
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811353111.5A Active CN109264985B (en) | 2018-11-14 | 2018-11-14 | Degassing method and device for optical fiber preform |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109264985B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110885184B (en) * | 2019-10-25 | 2022-04-29 | 烽火通信科技股份有限公司 | Common-rail optical fiber drawing device and drawing method thereof |
| CN111186999B (en) * | 2020-02-18 | 2024-03-12 | 通鼎互联信息股份有限公司 | A vacuum drawing furnace for optical fiber manufacturing |
| CN113248131B (en) * | 2021-05-31 | 2021-09-17 | 中天科技精密材料有限公司 | Optical fiber preform, and apparatus and method for manufacturing the same |
| CN113277728B (en) * | 2021-07-01 | 2023-06-09 | 中国计量大学 | An optical fiber drawing furnace suitable for fluoride glass |
| CN115947537B (en) * | 2022-12-24 | 2024-07-19 | 藤仓烽火光电材料科技有限公司 | Surface treatment device and surface treatment method for quartz core rod |
| CN118598501B (en) * | 2024-08-08 | 2024-11-15 | 江苏亨通光导新材料有限公司 | A low water peak optical fiber preform helium-free sintering device and use method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101781087A (en) * | 2010-02-09 | 2010-07-21 | 中天科技精密材料有限公司 | Equipment for loose body optical fiber prefabricated rod integral sintering desaeration and method thereof |
| WO2014032476A1 (en) * | 2012-08-28 | 2014-03-06 | 长飞光纤光缆有限公司 | Wiredrawing method and apparatus for outer diameter fluctuation optical fiber preform |
| CN105753311A (en) * | 2016-02-04 | 2016-07-13 | 长飞光纤光缆股份有限公司 | Device and method for degassing optical fiber preform rods |
| CN105916823A (en) * | 2014-01-16 | 2016-08-31 | 古河电气工业株式会社 | Method for producing optical fiber preform and method for producing optical fiber |
| CN106643131A (en) * | 2016-10-20 | 2017-05-10 | 北京华海中谊节能科技股份有限公司 | Movable type vertical vacuum furnace structure |
-
2018
- 2018-11-14 CN CN201811353111.5A patent/CN109264985B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101781087A (en) * | 2010-02-09 | 2010-07-21 | 中天科技精密材料有限公司 | Equipment for loose body optical fiber prefabricated rod integral sintering desaeration and method thereof |
| WO2014032476A1 (en) * | 2012-08-28 | 2014-03-06 | 长飞光纤光缆有限公司 | Wiredrawing method and apparatus for outer diameter fluctuation optical fiber preform |
| CN105916823A (en) * | 2014-01-16 | 2016-08-31 | 古河电气工业株式会社 | Method for producing optical fiber preform and method for producing optical fiber |
| CN105753311A (en) * | 2016-02-04 | 2016-07-13 | 长飞光纤光缆股份有限公司 | Device and method for degassing optical fiber preform rods |
| CN106643131A (en) * | 2016-10-20 | 2017-05-10 | 北京华海中谊节能科技股份有限公司 | Movable type vertical vacuum furnace structure |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109264985A (en) | 2019-01-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109264985B (en) | Degassing method and device for optical fiber preform | |
| US5713979A (en) | Heat treatment facility for synthetic vitreous silica bodies | |
| JP5038435B2 (en) | Synthetic quartz glass hollow cylinder manufacturing method and thick hollow cylinder by the manufacturing method | |
| CN103626381B (en) | A kind of graphite furnace for sintered glass loose media | |
| WO2021184713A1 (en) | Sintering device and sintering method for optical fiber preform soot body | |
| CN109133593B (en) | Optical fiber drawing annealing device | |
| WO2018036142A1 (en) | Sintering device with casing tube for optical fibre preform rod and sintering method therefor | |
| CN110818238A (en) | Annealing device and method for improving stress of preform | |
| US3625669A (en) | Fiber optic bundle fusion | |
| CN111186999A (en) | A vacuum drawing furnace for optical fiber manufacturing | |
| CN202849232U (en) | Graphite furnace for sintering glass loose mass | |
| US20150135772A1 (en) | Furnace for Sintering Silica Soot Bodies | |
| CN209226836U (en) | A kind of preform degasification furnace | |
| JP2831802B2 (en) | Manufacturing method of optical fiber preform | |
| CN211999485U (en) | Double-layer vacuum dehydroxylation annealing device | |
| US5653779A (en) | Method for manufacturing quartz glass components and molding frame therefor | |
| KR102365316B1 (en) | Variable diameter seals for optical substrate furnaces | |
| CN211896679U (en) | Vacuum wire drawing furnace for manufacturing optical fiber | |
| CN110923676B (en) | Annealing equipment and process for multispectral zinc sulfide window | |
| JP4062407B2 (en) | Glass base material manufacturing method and manufacturing apparatus | |
| CN1781863B (en) | Apparatus and method for manufacturing glass preforms | |
| CN119143377A (en) | Optical fiber preform loose body integrated sintering furnace and sintering method thereof | |
| CN219233931U (en) | A preparation device for polycrystalline germanium optical window | |
| RU2772026C1 (en) | Method for manufacturing structural block from glasses of different compositions and device for its implementation | |
| CN209522763U (en) | A kind of optical fiber prefabricating stick cladding sintering furnace |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB03 | Change of inventor or designer information | ||
| CB03 | Change of inventor or designer information |
Inventor after: Zhang Xuejun Inventor after: Zheng Wei Inventor before: Zhang Xuejun |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |