CN109721237B - Production process of optical fiber preform and optical fiber preform - Google Patents
Production process of optical fiber preform and optical fiber preform Download PDFInfo
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- CN109721237B CN109721237B CN201910128912.XA CN201910128912A CN109721237B CN 109721237 B CN109721237 B CN 109721237B CN 201910128912 A CN201910128912 A CN 201910128912A CN 109721237 B CN109721237 B CN 109721237B
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- 239000013307 optical fiber Substances 0.000 title claims abstract description 44
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 26
- 238000010438 heat treatment Methods 0.000 claims abstract description 143
- 238000000034 method Methods 0.000 claims abstract description 70
- 238000005137 deposition process Methods 0.000 claims abstract description 8
- 238000004017 vitrification Methods 0.000 claims abstract description 5
- 229910052751 metal Inorganic materials 0.000 claims description 54
- 239000002184 metal Substances 0.000 claims description 54
- 239000011159 matrix material Substances 0.000 claims description 15
- 230000008719 thickening Effects 0.000 claims description 15
- 239000000758 substrate Substances 0.000 claims description 14
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 13
- 238000000151 deposition Methods 0.000 claims description 12
- 238000005245 sintering Methods 0.000 claims description 10
- 238000005096 rolling process Methods 0.000 claims description 9
- 239000002245 particle Substances 0.000 claims description 6
- 235000012239 silicon dioxide Nutrition 0.000 claims description 6
- 239000000377 silicon dioxide Substances 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 5
- 230000018044 dehydration Effects 0.000 claims 1
- 238000006297 dehydration reaction Methods 0.000 claims 1
- 230000007547 defect Effects 0.000 abstract description 5
- 230000001276 controlling effect Effects 0.000 description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 5
- 239000001301 oxygen Substances 0.000 description 5
- 229910052760 oxygen Inorganic materials 0.000 description 5
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 239000005049 silicon tetrachloride Substances 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 2
- 230000008602 contraction Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 229910052582 BN Inorganic materials 0.000 description 1
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- 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
-
- 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
- C03B37/01807—Reactant delivery systems, e.g. reactant deposition burners
- C03B37/01815—Reactant deposition burners or deposition heating means
-
- 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
- C03B37/01861—Means for changing or stabilising the diameter or form of tubes or rods
-
- 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
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
本发明公开了一种光纤预制棒的生产工艺，包括以下步骤:1)芯棒沉积工序；2)玻璃化工序；3)粗延伸工序第一阶段；4)粗延伸工序第二阶段；5)粗延伸工序第三阶段；步骤3)和步骤5)中辅助加热装置包括一对并列布置的伸缩铰架、推杆和若各个发热金属丝；所述伸缩铰架包括第一连杆、第二连杆、第三连杆、第四连杆、第五连杆和第六连杆；发热金属丝为弧形线圈，上下相邻的发热金属丝通过弹性导电片相连；推杆驱动伸缩铰架展开或收缩；发热金属丝上分别连接电源正极和负极。本发明采用一种全新的生产工艺和辅助加热设备，解决了现有的光纤预制棒在延伸过程出现各部分尺寸相差较大的缺陷。
The invention discloses a production process for an optical fiber preform, comprising the following steps: 1) a core rod deposition process; 2) a vitrification process; 3) a first stage of a rough extension process; 4) a second stage of the rough extension process; 5) The third stage of the rough extension process; in steps 3) and 5), the auxiliary heating device includes a pair of parallelly arranged telescopic hinges, push rods and each heating wire; the telescopic hinges include a first link, a second The connecting rod, the third connecting rod, the fourth connecting rod, the fifth connecting rod and the sixth connecting rod; the heating wire is an arc coil, and the upper and lower adjacent heating wires are connected by elastic conductive sheets; the push rod drives the telescopic hinge Expand or shrink; the positive and negative electrodes of the power supply are respectively connected to the heating wire. The invention adopts a brand-new production process and auxiliary heating equipment, and solves the defect that the size of each part of the existing optical fiber preform is greatly different in the extension process.
Description
The application is a divisional application with application date of 2017, 02, 15 and application number of 201710081160.7, and is named as a production process of a large-size optical fiber preform and the large-size optical fiber preform thereof.
Technical Field
The invention relates to the field of optical fiber perform production, in particular to a production process of a large-size optical fiber perform.
Background
The optical fiber preform is a core raw material for manufacturing a silica-based optical fiber. The internal structure of the optical fiber is formed in the preform, and thus the fabrication of the preform is the most important part of the optical fiber process. There are various methods for manufacturing the optical fiber preform, and a commonly used manufacturing process is a gas phase oxidation method. In the gas phase oxidation process, high purity halide vapor and oxygen react to form oxide particles which are deposited on the surface of a glass or quartz body (or the inner wall of a tubular body) and then sintered to form a transparent glass rod.
In order to have a higher deposition rate, the preparation of the preform generally adopts a method of preparing a large-size core rod, then thinning the core rod, and then depositing a cladding layer outside the core rod. In the stretching process of the core rod of the large-size optical fiber preform rod, the diameter of the starting end of the core rod is smaller after stretching; at the end of the drawing, the tail end of the mandrel is insufficiently melted, resulting in a larger diameter in this portion. The part with the smaller diameter of the core rod is usually removed and is not used in the actual use process, so that the product waste is caused, and the cost is increased.
Disclosure of Invention
The invention provides a production process of a large-size optical fiber preform aiming at the problems, and solves the defect that the existing production process of the large-size optical fiber preform is easy to cause uneven size of the preform.
The technical scheme adopted by the invention is as follows:
a production process of a large-size optical fiber preform comprises the following steps:
1) a core rod deposition process: introducing silicon tetrachloride, hydrogen and oxygen into an oxyhydrogen blast burner on a mandrel lathe, depositing and sintering, and attaching generated silicon dioxide particles on a seed rod to form a mandrel matrix; in the process of depositing and sintering the tail end of the core rod substrate, the outer diameter of the tail end of the core rod substrate with the length of 10 mm-20 mm is larger than that of the other parts by 6 mm-10 mm by reducing the lifting rate of the seed rod;
2) a vitrification step: the obtained core rod matrix is melted and dehydrated at the temperature of 1800-2000 ℃ to obtain a vitrified core rod;
3) first stage of rough extension process: transferring the vitrified core rod into a high-temperature furnace for heating and extending, wherein the temperature of the high-temperature furnace is controlled to be 2000-2200 ℃, and an auxiliary heating device is extended to a core rod thickening area, so that the temperature of the core rod thickening area exceeds 2300 ℃; further heating and extending, and controlling the air return speed to be 10-15 cm/s;
4) and a second stage of the rough extension process: removing the auxiliary heating device, controlling the temperature of the high-temperature furnace at 2000-2200 ℃, further heating and extending, and controlling the air return speed to be 20-25 cm/s;
5) rough extension process third stage: the temperature of the high-temperature furnace is controlled to be 2100-2300 ℃, the high-temperature furnace is further heated and extended, and the air speed of return air is controlled to be 30-35 cm/s; the auxiliary heating device is arranged at one end of the core rod far away from the thickening area, so that the local temperature rises to exceed 2300 ℃; after the extension is finished, cooling, and making the outer diameter of the thickened area of the core rod larger than the outer diameter of the middle area of the core rod by 3-4 mm;
the auxiliary heating device in the step 3) and the step 5) comprises a pair of telescopic hinge brackets which are arranged in parallel, a push rod and a plurality of heating metal wires;
the telescopic hinge frame comprises a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod, a fifth connecting rod and a sixth connecting rod; one end of the first connecting rod is fixedly connected with the push rod, and the other end of the first connecting rod is hinged with the heating metal wire; the second connecting rod is fixedly connected with the push rod, and the other end of the second connecting rod is hinged with the heating metal wire; the middle parts of the first connecting rod and the second connecting rod are hinged in a crossed manner; one end of the third connecting rod is hinged with the connecting point of the first connecting rod and the heating metal wire, and the other end of the third connecting rod is hinged with the heating metal wire; the fourth connecting rod is hinged with the connecting point of the second connecting rod and the heating metal wire, and the other end of the fourth connecting rod is hinged with the heating metal wire; the middle parts of the third connecting rod and the fourth connecting rod are hinged in a crossed manner; one end of the fifth connecting rod is hinged with a connecting point of the third connecting rod and the heating metal wire, and the other end of the fifth connecting rod is hinged with the heating metal wire; the sixth connecting rod is hinged with the connecting point of the fourth connecting rod and the heating metal wire, and the other end of the sixth connecting rod is hinged with the heating metal wire; the middle parts of the fifth connecting rod and the sixth connecting rod are hinged in a crossed manner; the heating metal wires are arc-shaped coils, and the heating metal wires which are adjacent up and down are connected through elastic conducting strips;
the push rod is connected with the other end, away from the third connecting rod or the fourth connecting rod, of the first connecting rod or the second connecting rod; the push rod drives the telescopic hinged frame to expand or contract; the heating metal wire connected with the first connecting rod or the second connecting rod is respectively connected with the anode and the cathode of the power supply.
According to the production process of the large-size optical fiber preform rod, in the core rod deposition process, the outer diameter of the 10-20 mm length of the tail end of the core rod substrate is larger than that of the other parts by 6-10 mm, and the diameter reduction of the starting end easily caused in the subsequent extension process is compensated. Meanwhile, the coarse extension process is divided into three different stages which are respectively regulated and controlled, and an auxiliary heating device is used for the first stage to carry out compensation type heating, so that the temperature of the initial end is higher, the heat transfer is faster, and the heat is more rapidly transferred to the inner core of the matrix; making the initial stretching process more rapid, reducing diameter reduction and reducing possible waste. And then, an auxiliary heating device is used in the third stage to compensate the heat lost in the stage and increase the circulation of hot air, so that the heat transfer is more uniform, and the defect that the size of the extending tail end of the prefabricated rod is larger is reduced. The auxiliary heating device is stable in heating, the distance between the heating metal wires can be adjusted by adjusting the push rod, the heating temperature and the range of the heating area are further adjusted, and the auxiliary heating device is simple and convenient to operate.
Optionally, in the step 3), the telescopic hinge frame is in a contracted state, so that the vertical distance between the plurality of heating metal wires is smaller. The up-down distance between the heating metal wires is smaller, so that the heat is more concentrated, the heating temperature is higher, and the heat is more rapidly transferred to the inner core of the matrix.
Optionally, in the step 5), the telescopic hinge frame is in an expanded state, so that the vertical distance between the plurality of heating wires is larger. The heat is uniformly dispersed due to the large up-down distance between the heating wires.
Optionally, the production process of the large-size optical fiber preform further comprises a pre-fine-rolling process; the pre-fine-rolling procedure comprises the following steps: heating the thickened area of the core rod for accurate extension, so that the difference between the outer diameter of the thickened area of the core rod and the outer diameter of the middle area of the core rod is less than or equal to 2 mm; the pre-fine stretching process is after the third stage of the coarse stretching process. The local thicker part of the obtained prefabricated rod is pre-extended by adopting a pre-fine extension process, so that the accurate control of the equal-proportion extension of the subsequent fine extension process is facilitated.
Optionally, the elastic conductive sheet is made of a high-temperature-resistant conductive heating wire which is the same as the heating wire.
Optionally, the auxiliary heating device further comprises a driving motor and a control unit, the control unit is electrically connected with the driving motor, the driving motor is provided with four pull rods, the four pull rods are respectively connected with the four push rods, and the driving motor drives the pull rods to move so as to drive the push rods to move horizontally.
The invention also discloses a large-size optical fiber preform rod which is manufactured by utilizing the large-size optical fiber preform rod process.
The invention has the beneficial effects that: according to the production process of the large-size optical fiber preform rod, in the core rod deposition process, the outer diameter of the 10-20 mm length of the tail end of the core rod substrate is larger than that of the other parts by 6-10 mm, and the diameter reduction of the starting end easily caused in the subsequent extension process is compensated. Simultaneously with the thick extension process division three different stages, regulate and control respectively, use auxiliary heating device to first stage, carry out the offset heating for the temperature of initial end is higher, and heat transfer is faster, makes tensile process more rapidly in the initial time, has reduced the reduction of diameter and has reduced possible waste. And then, an auxiliary heating device is used in the third stage to compensate the heat lost in the stage and increase the circulation of hot air, so that the heat transfer is more uniform, and the defect that the size of the extending tail end of the prefabricated rod is larger is reduced. The auxiliary heating device is stable in heating, the distance between the heating metal wires can be adjusted by adjusting the push rod, the heating temperature and the range of the heating area are further adjusted, and the auxiliary heating device is simple and convenient to operate.
In addition, the telescopic hinged frame is in a contraction state, so that the vertical distance between the plurality of heating metal wires is smaller. The up-down distance between the heating metal wires is smaller, so that the heat is more concentrated, the heating temperature is higher, and the heat is more rapidly transferred to the inner core of the matrix. The telescopic hinged frame is in an expansion state, so that the up-down distance between the plurality of heating metal wires is larger. The heat is uniformly dispersed due to the large up-down distance between the heating wires. The local thicker part of the obtained preform is pre-extended by adopting a pre-fine extension process, so that the accurate control of the equal-proportion extension of the subsequent fine extension process is facilitated.
Description of the drawings:
FIG. 1 is a schematic view of a process for producing a large-sized optical fiber preform according to the present invention;
FIG. 2 is a schematic view of an auxiliary heating apparatus for a process of manufacturing a large-sized optical fiber preform;
FIG. 3 is a schematic view showing a structure of a telescopic hinge frame in an auxiliary heating apparatus for a process of manufacturing a large-sized optical fiber preform;
FIG. 4 is a schematic view showing the structure of an auxiliary heating device for a large-sized optical fiber preform rod in cooperation with the preform rod.
The figures are numbered:
1. a telescopic hinge frame; 2. a push rod; 3. a heat generating wire; 4. a first link; 5. a second link; 6. a third link; 7. a fourth link; 8. a fifth link; 9. a sixth link; 10. an elastic conductive sheet; 12. a pull rod; 14. a control unit; 15. a high temperature furnace.
The specific implementation mode is as follows:
the present invention will be described in detail below with reference to the accompanying drawings.
The large size referred to in the present invention generally means a preform having a diameter of 120mm or more.
The invention discloses a large-size optical fiber preform rod which is manufactured by utilizing the large-size optical fiber preform rod process.
The first embodiment is as follows: the invention also discloses a production process of the large-size optical fiber preform (see the attached figure 1), which comprises the following steps:
1) a core rod deposition process: introducing silicon tetrachloride, hydrogen and oxygen into an oxyhydrogen blast burner on a mandrel lathe, depositing and sintering, and attaching generated silicon dioxide particles on a seed rod to form a mandrel matrix; in the process of depositing and sintering at the tail end of the core rod substrate, the outer diameter of the 10mm length of the tail end of the core rod substrate is larger than that of the other parts by 6mm through reducing the lifting rate of the seed rod;
2) a vitrification step: the obtained core rod matrix is melted and dehydrated at the temperature of 1800 ℃ to obtain a vitrified core rod;
3) first stage of rough extension process: transferring the vitrified core rod into a high-temperature furnace 15 for heating and extending, controlling the temperature of the high-temperature furnace 15 at 2000 ℃, and extending an auxiliary heating device to a core rod thickening area to ensure that the temperature of the core rod thickening area is 2300 ℃; further heating and extending, and controlling the air return speed to be 10 cm/s;
4) and a second stage of the rough extension process: removing the auxiliary heating device, controlling the temperature of the high-temperature furnace 15 at 2000 ℃, further heating and extending, and controlling the return air speed to be 20 cm/s;
5) rough extension process third stage: the temperature of the high-temperature furnace 15 is controlled to be 2100 ℃, the high-temperature furnace is further heated and extended, and the air speed of return air is controlled to be 30 cm/s; the auxiliary heating device is arranged at one end of the core rod far away from the thickening area, so that the local temperature rises to exceed 2300 ℃; after the extension is finished, cooling, and making the outer diameter of the thickened area of the core rod larger than that of the middle area of the core rod by 3 mm;
6) pre-fine-rolling procedure: and heating the thickened area of the core rod for accurate extension, so that the difference between the outer diameter of the thickened area of the core rod and the outer diameter of the middle area of the core rod is equal to 2 mm.
Example two: the invention also discloses a production process of the large-size optical fiber preform, which comprises the following steps:
1) a core rod deposition process: introducing silicon tetrachloride, hydrogen and oxygen into an oxyhydrogen blast burner on a mandrel lathe, depositing and sintering, and attaching generated silicon dioxide particles on a seed rod to form a mandrel matrix; in the process of depositing and sintering at the tail end of the core rod substrate, the outer diameter of the 20mm length of the tail end of the core rod substrate is larger than that of the other parts by reducing the lifting rate of the seed rod;
2) a vitrification step: the obtained core rod matrix is melted and dehydrated at the temperature of 2000 ℃ to obtain a vitrified core rod;
3) first stage of rough extension process: transferring the vitrified core rod into a high-temperature furnace for heating and extending, controlling the temperature of the high-temperature furnace 15 at 2200 ℃, and extending into an auxiliary heating device to a core rod thickening area to ensure that the temperature of the core rod thickening area is 2300 ℃; further heating and extending, and controlling the air return speed to be 15 cm/s;
4) and a second stage of the rough extension process: removing the auxiliary heating device, controlling the temperature of the high-temperature furnace 15 at 2200 ℃, further heating and extending, and controlling the return air speed to be 25 cm/s;
5) rough extension process third stage: the temperature of the high-temperature furnace 15 is controlled to be 2300, the high-temperature furnace is further heated and extended, and the air return speed is controlled to be 35 cm/s; the auxiliary heating device is arranged at one end of the core rod far away from the thickening area, so that the local temperature rises to exceed 2300 ℃; after the extension is finished, cooling, and making the outer diameter of the thickened area of the core rod 4mm larger than that of the middle area of the core rod;
6) pre-fine-rolling procedure: and heating the thickened area of the core rod for accurate extension, so that the difference between the outer diameter of the thickened area of the core rod and the outer diameter of the middle area of the core rod is equal to 2 mm.
In the step 3), the telescopic hinge frame 1 is in a contraction state, so that the vertical distance between the plurality of heating metal wires 3 is smaller. The up-down distance between the heating metal wires 3 is smaller, so that the heat is more concentrated, the heating temperature is higher, and the heat is more rapidly transferred to the inner core of the matrix.
In the step 5), the telescopic hinge frame 1 is in an expanded state, so that the vertical distance between the plurality of heating metal wires 3 is larger. The large up-down distance between the heating wires 3 makes the heat be dispersed uniformly.
According to the production process of the large-size optical fiber preform rod, in the core rod deposition process, the outer diameter of the 10-20 mm length of the tail end of the core rod substrate is larger than that of the other parts by 6-10 mm, and the diameter reduction of the starting end easily caused in the subsequent extension process is compensated. Meanwhile, the coarse extension process is divided into three different stages which are respectively regulated and controlled, and an auxiliary heating device is used for the first stage to carry out compensation type heating, so that the temperature of the initial end is higher, the heat transfer is faster, and the heat is more rapidly transferred to the inner core of the matrix; making the initial stretching process more rapid, reducing diameter reduction and reducing possible waste. And then, an auxiliary heating device is used in the third stage to compensate the heat lost in the stage and increase the circulation of hot air, so that the heat transfer is more uniform, and the defect that the size of the extending tail end of the prefabricated rod is larger is reduced.
The invention discloses an auxiliary heating device (shown in attached figures 2, 3 and 4), which comprises a pair of telescopic hinged brackets 1, a push rod 2 and a plurality of heating metal wires 3 which are arranged in parallel;
the telescopic hinge frame 1 comprises a first connecting rod 4, a second connecting rod 5, a third connecting rod 6, a fourth connecting rod 7, a fifth connecting rod 8 and a sixth connecting rod 9; one end of the first connecting rod 4 is fixedly connected with the push rod 2, and the other end of the first connecting rod is hinged with the heating metal wire 3; the second connecting rod 5 is fixedly connected with the push rod 2, and the other end of the second connecting rod is hinged with the heating metal wire 3; the middle parts of the first connecting rod 4 and the second connecting rod 5 are hinged in a crossed manner; one end of the third connecting rod 6 is hinged with the connecting point of the first connecting rod 4 and the heating metal wire 3, and the other end is hinged with the heating metal wire 3; the fourth connecting rod 7 is hinged with the connecting point of the second connecting rod 5 and the heating metal wire 3, and the other end of the fourth connecting rod is hinged with the heating metal wire 3; the middle parts of the third connecting rod 6 and the fourth connecting rod 7 are hinged in a crossed manner; one end of the fifth connecting rod 8 is hinged with the connecting point of the third connecting rod 6 and the heating metal wire 3, and the other end is hinged with the heating metal wire 3; the sixth connecting rod 9 is hinged with the connecting point of the fourth connecting rod 7 and the heating metal wire 3, and the other end of the sixth connecting rod is hinged with the heating metal wire 3; the middle parts of the fifth connecting rod 8 and the sixth connecting rod 9 are hinged in a crossed manner; the heating metal wires 3 are arc-shaped coils, and the heating metal wires 3 which are adjacent up and down are connected through an elastic conducting strip 10;
the push rod 2 is connected with the other end of the first connecting rod 4 or the second connecting rod 5 far away from the third connecting rod 6 or the fourth connecting rod 7; the push rod 2 drives the telescopic hinge frame 1 to expand or contract; the heating wire 3 connected with the first connecting rod 4 or the second connecting rod 5 is respectively connected with the anode and the cathode of a power supply.
The auxiliary heating device is stable in heating, the distance between the heating metal wires 3 can be adjusted by adjusting the push rod 2, the heating temperature and the range of a heating area are further adjusted, and the operation is simple and convenient.
The production process of the large-size optical fiber preform further comprises a pre-fine-rolling procedure; the pre-fine-rolling procedure comprises the following steps: heating the thickened area of the core rod for accurate extension, so that the difference between the outer diameter of the thickened area of the core rod and the outer diameter of the middle area of the core rod is equal to 2 mm; the pre-fine stretching process is after the third stage of the coarse stretching process. The local thicker part of the obtained prefabricated rod is pre-extended by adopting a pre-fine extension process, so that the accurate control of the equal-proportion extension of the subsequent fine extension process is facilitated.
The elastic conducting strip 10 adopts the high-temperature resistant conducting heating metal wire 3 which is the same as the heating metal wire 3.
The auxiliary heating device further comprises a driving motor and a control unit 14, the control unit 14 is electrically connected with the driving motor, the driving motor is provided with four pull rods 12, the four pull rods 12 are respectively connected with four push rods 2, and the driving motor drives the pull rods 12 to move so as to drive the push rods 2 to move horizontally.
The control unit 14 in this embodiment is a computer system. Tungsten wire may be used for the heating wire 3 and the elastic conductive sheet 10 in the present invention. The telescopic hinge frame 1 may be made of a high temperature resistant ceramic such as boron nitride ceramic.
When the invention is implemented, the production process of the large-size optical fiber preform adopts the following steps:
1) introducing silicon tetrachloride, hydrogen and oxygen into an oxyhydrogen blast burner on a mandrel lathe, depositing and sintering to generate silicon dioxide particles which are attached to a seed rod to form a mandrel matrix; in the process of depositing and sintering at the tail end of the core rod substrate, the outer diameter of the 10mm length of the tail end of the core rod substrate is larger than that of the other parts by 6mm through reducing the lifting rate of the seed rod; 2) melting and dehydrating the obtained core rod matrix at the temperature of 1800 ℃, and vitrifying to obtain a vitrified core rod; 3) transferring the vitrified core rod into a high-temperature furnace for heating and extending, controlling the temperature of the high-temperature furnace to be 2000 ℃, and extending into an auxiliary heating device to a core rod thickening area to ensure that the temperature of the core rod thickening area is 2300 ℃; further heating and extending, and controlling the air return speed to be 10 cm/s; 4) removing the auxiliary heating device, controlling the temperature of the high-temperature furnace at 2000 ℃, further heating and extending, and controlling the air return speed to be 20 cm/s; 5) the temperature of the high-temperature furnace is controlled at 2100 ℃, the high-temperature furnace is further heated and extended, and the air speed of return air is controlled to be 30 cm/s; the auxiliary heating device is arranged at one end of the core rod far away from the thickening area, so that the local temperature rises to exceed 2300 ℃; after the extension is finished, cooling, and making the outer diameter of the thickened area of the core rod larger than that of the middle area of the core rod by 3 mm; 6) the pre-fine-rolling procedure comprises the following steps: and heating the thickened area of the core rod for accurate extension, so that the difference between the outer diameter of the thickened area of the core rod and the outer diameter of the middle area of the core rod is equal to 2 mm.
The above description is only for the preferred embodiment of the present invention and is not intended to limit the scope of the present invention, and all equivalent structural changes made by using the contents of the present specification and the drawings can be directly or indirectly applied to other related technical fields and are included in the scope of the present invention.
Claims (8)
1. A process for producing an optical fiber preform, comprising the steps of:
1) a core rod deposition process: depositing and sintering on a mandrel lathe through an oxyhydrogen blast burner, and attaching the generated silicon dioxide particles on a seed rod to form a mandrel matrix; in the process of depositing and sintering at the tail end of the core rod substrate, the outer diameter of the tail end of the core rod substrate is larger than other parts by reducing the lifting rate of the seed rod;
2) a vitrification step: carrying out melt dehydration operation on the obtained core rod to obtain a vitrified core rod;
3) first stage of rough extension process: transferring the vitrified core rod into a high-temperature furnace for heating and extending, wherein the temperature of the high-temperature furnace is controlled to be 2000-2200 ℃, and the high-temperature furnace is extended into an auxiliary heating device to reach a core rod thickening area, so that the temperature of the core rod thickening area exceeds 2300 ℃; further heating and extending, and controlling the air return speed to be 10-15 cm/s;
4) and a second stage of the rough extension process: removing the auxiliary heating device, controlling the temperature of the high-temperature furnace at 2000-2200 ℃, further heating and extending, and controlling the air return speed at 20-25 cm/s;
5) rough extension process third stage: the temperature of the high-temperature furnace is controlled to be 2100-2300 ℃, the high-temperature furnace is further heated and extended, and the air speed of return air is controlled to be 30-35 cm/s; the auxiliary heating device is arranged at one end of the core rod far away from the thickening area, so that the local temperature rises to exceed 2300 ℃; after the extension is finished, cooling, wherein the outer diameter of the thickened area of the prepared core rod is larger than that of the middle area of the core rod;
the auxiliary heating device in the step 3) and the step 5) comprises a pair of telescopic hinge brackets which are arranged in parallel, a push rod and a plurality of heating metal wires;
the telescopic hinge frame comprises a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod, a fifth connecting rod and a sixth connecting rod; one end of the first connecting rod is fixedly connected with the push rod, and the other end of the first connecting rod is hinged with the heating metal wire; the second connecting rod is fixedly connected with the push rod, and the other end of the second connecting rod is hinged with the heating metal wire; the middle parts of the first connecting rod and the second connecting rod are hinged in a crossed manner; one end of the third connecting rod is hinged with the connecting point of the first connecting rod and the heating metal wire, and the other end of the third connecting rod is hinged with the heating metal wire; the fourth connecting rod is hinged with the connecting point of the second connecting rod and the heating metal wire, and the other end of the fourth connecting rod is hinged with the heating metal wire; the middle parts of the third connecting rod and the fourth connecting rod are hinged in a crossed manner; one end of the fifth connecting rod is hinged with a connecting point of the third connecting rod and the heating metal wire, and the other end of the fifth connecting rod is hinged with the heating metal wire; the sixth connecting rod is hinged with the connecting point of the fourth connecting rod and the heating metal wire, and the other end of the sixth connecting rod is hinged with the heating metal wire; the middle parts of the fifth connecting rod and the sixth connecting rod are hinged in a crossed manner; the heating metal wires are arc-shaped coils, and the heating metal wires which are adjacent up and down are connected through elastic conducting strips;
the push rod is connected with the other end, away from the third connecting rod or the fourth connecting rod, of the first connecting rod or the second connecting rod; the push rod drives the telescopic hinged frame to expand or contract; the heating metal wire connected with the first connecting rod or the second connecting rod is respectively connected with the anode and the cathode of the power supply.
2. The process for producing an optical fiber preform according to claim 1, wherein in the step 1), the outer diameter of the end of the core rod substrate having a length of 10mm to 20mm is made larger than that of the other portion by 6mm to 10 mm; in the step 2), the core rod matrix is melted and dehydrated at the temperature of 1800-2000 ℃; in the step 5), the outer diameter of the thickened area of the prepared core rod is 3-4 mm larger than that of the middle area of the core rod.
3. A process for fabricating an optical fiber preform according to claim 1, wherein in the step 3), the telescopic hinge is contracted so that the upper and lower spaces between the plurality of heating wires are smaller.
4. A process for fabricating an optical fiber preform according to claim 1, wherein in the step 5), the telescopic hinge is in an expanded state so that the upper and lower spaces between the plurality of heating wires are larger.
5. A process for the production of an optical fiber preform according to claim 3, further comprising a pre-finish-rolling process; the pre-fine-rolling procedure comprises the following steps: heating the thickened area of the core rod for accurate extension, so that the difference between the outer diameter of the thickened area of the core rod and the outer diameter of the middle area of the core rod is less than or equal to 2 mm; the pre-fine stretching process is after the third stage of the coarse stretching process.
6. A process for fabricating an optical fiber preform according to claim 1, wherein the elastic conductive sheet is made of a high temperature resistant conductive heating wire identical to the heating wire.
7. The process for manufacturing an optical fiber preform according to claim 1, wherein the auxiliary heating device further comprises a driving motor and a control unit, the control unit is electrically connected to the driving motor, the driving motor has four pull rods, the four pull rods are respectively connected to four push rods, and the driving motor drives the pull rods to move, thereby driving the push rods to move horizontally.
8. An optical fiber preform, characterized in that it is produced by a process for producing an optical fiber preform according to any one of claims 1 to 7.
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| CN201710081160.7A CN106904821B (en) | 2017-02-15 | 2017-02-15 | The production technology and its large-scale optical fiber prefabricating stick of large-scale optical fiber prefabricating stick |
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| CN111320374B (en) * | 2018-12-15 | 2023-09-26 | 中天科技精密材料有限公司 | Optical fiber preform and method for manufacturing the same |
| CN116970881B (en) * | 2023-09-22 | 2023-12-19 | 连云港天舒热处理科技有限公司 | Heat treatment equipment for nonferrous metal processing |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1078309A (en) * | 1992-01-30 | 1993-11-10 | 古河电气工业株式会社 | The manufacture method of fibre-optical preform |
| CN1482082A (en) * | 2002-09-06 | 2004-03-17 | 江苏法尔胜光子有限公司 | Sintering process for manufacturing prefabricated fiber rod |
| JP2004338970A (en) * | 2003-05-13 | 2004-12-02 | Sumitomo Electric Ind Ltd | Manufacturing method of glass base material |
| CN1579977A (en) * | 2003-08-08 | 2005-02-16 | 住友电气工业株式会社 | Optical fiber preform, optical fiber, and manufacturing methods thereof |
| CN1656030A (en) * | 2002-06-19 | 2005-08-17 | 住友电气工业株式会社 | Method for stretching glass base material and stretching device used for the method |
| CN101328013A (en) * | 2007-06-22 | 2008-12-24 | 江苏亨通光纤科技有限公司 | Method for drawing optical fiber from large-size optical fiber preform |
| CN101541694A (en) * | 2007-06-25 | 2009-09-23 | 住友电气工业株式会社 | Process for producing drawn glass body |
| CN101792256A (en) * | 2010-02-09 | 2010-08-04 | 中天科技精密材料有限公司 | Test method for large size optical fiber preforms |
| CN102627399A (en) * | 2012-04-18 | 2012-08-08 | 长飞光纤光缆有限公司 | Vertical stretch method and device of optical fiber prefabricating rod |
| CN104053634A (en) * | 2011-10-25 | 2014-09-17 | 赫罗伊斯石英玻璃股份有限两合公司 | Method for producing cylindrical glass components by stretching |
| CN106082632A (en) * | 2016-06-16 | 2016-11-09 | 中天科技精密材料有限公司 | A kind of interior chemical vapor deposition method of pipe that automatically eliminates prepares glass tubing bow degree method during preform |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3625632B2 (en) * | 1997-12-04 | 2005-03-02 | 古河電気工業株式会社 | Drawing method of glass base material for optical fiber |
| CN1194916C (en) * | 2002-10-23 | 2005-03-30 | 长飞光纤光缆有限公司 | PCVD process of making optical fiber rod in high deposition rate |
| KR100896103B1 (en) * | 2003-03-10 | 2009-05-07 | 엘에스전선 주식회사 | Optical fiber base material manufacturing device that can reduce soot |
| US20070062337A1 (en) * | 2003-06-30 | 2007-03-22 | Guojun Dai | Method and apparatus for drilling preforms for holey optical fibers |
| JP2007223824A (en) * | 2006-02-21 | 2007-09-06 | Shin Etsu Chem Co Ltd | Method for sintering porous glass preform |
| CN101428964B (en) * | 2008-09-23 | 2011-01-12 | 富通集团有限公司 | A method for preparing the cladding of a large-scale optical fiber preform |
| CN101811822B (en) * | 2010-04-16 | 2012-03-07 | 长飞光纤光缆有限公司 | Method for manufacturing large-diameter optical fiber mandril through PCVD process |
| JP6459585B2 (en) * | 2015-02-10 | 2019-01-30 | 住友電気工業株式会社 | Optical fiber preform manufacturing method |
-
2017
- 2017-02-15 CN CN201910128912.XA patent/CN109721237B/en active Active
- 2017-02-15 CN CN201710081160.7A patent/CN106904821B/en active Active
- 2017-02-15 CN CN201910129028.8A patent/CN109704561B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1078309A (en) * | 1992-01-30 | 1993-11-10 | 古河电气工业株式会社 | The manufacture method of fibre-optical preform |
| CN1656030A (en) * | 2002-06-19 | 2005-08-17 | 住友电气工业株式会社 | Method for stretching glass base material and stretching device used for the method |
| CN1482082A (en) * | 2002-09-06 | 2004-03-17 | 江苏法尔胜光子有限公司 | Sintering process for manufacturing prefabricated fiber rod |
| JP2004338970A (en) * | 2003-05-13 | 2004-12-02 | Sumitomo Electric Ind Ltd | Manufacturing method of glass base material |
| CN1579977A (en) * | 2003-08-08 | 2005-02-16 | 住友电气工业株式会社 | Optical fiber preform, optical fiber, and manufacturing methods thereof |
| CN101328013A (en) * | 2007-06-22 | 2008-12-24 | 江苏亨通光纤科技有限公司 | Method for drawing optical fiber from large-size optical fiber preform |
| CN101541694A (en) * | 2007-06-25 | 2009-09-23 | 住友电气工业株式会社 | Process for producing drawn glass body |
| CN101792256A (en) * | 2010-02-09 | 2010-08-04 | 中天科技精密材料有限公司 | Test method for large size optical fiber preforms |
| CN104053634A (en) * | 2011-10-25 | 2014-09-17 | 赫罗伊斯石英玻璃股份有限两合公司 | Method for producing cylindrical glass components by stretching |
| CN102627399A (en) * | 2012-04-18 | 2012-08-08 | 长飞光纤光缆有限公司 | Vertical stretch method and device of optical fiber prefabricating rod |
| CN106082632A (en) * | 2016-06-16 | 2016-11-09 | 中天科技精密材料有限公司 | A kind of interior chemical vapor deposition method of pipe that automatically eliminates prepares glass tubing bow degree method during preform |
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| CN106904821B (en) | 2019-03-22 |
| CN109704561B (en) | 2021-09-21 |
| CN109704561A (en) | 2019-05-03 |
| CN106904821A (en) | 2017-06-30 |
| CN109721237A (en) | 2019-05-07 |
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