CN111704357A - Drawing equipment and method for large-core-diameter single-polarization optical fiber - Google Patents
Drawing equipment and method for large-core-diameter single-polarization optical fiber Download PDFInfo
- Publication number
- CN111704357A CN111704357A CN202010696199.1A CN202010696199A CN111704357A CN 111704357 A CN111704357 A CN 111704357A CN 202010696199 A CN202010696199 A CN 202010696199A CN 111704357 A CN111704357 A CN 111704357A
- Authority
- CN
- China
- Prior art keywords
- temperature
- optical fiber
- drawing furnace
- wire drawing
- furnace
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 99
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000005491 wire drawing Methods 0.000 claims abstract description 114
- 238000000137 annealing Methods 0.000 claims abstract description 73
- 238000010438 heat treatment Methods 0.000 claims abstract description 17
- 238000005086 pumping Methods 0.000 claims abstract description 6
- 238000005520 cutting process Methods 0.000 claims abstract description 5
- 230000010287 polarization Effects 0.000 claims description 26
- 238000001816 cooling Methods 0.000 claims description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 12
- 239000001307 helium Substances 0.000 claims description 12
- 229910052734 helium Inorganic materials 0.000 claims description 12
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 12
- 239000007789 gas Substances 0.000 claims description 9
- 238000010926 purge Methods 0.000 claims description 8
- 238000000576 coating method Methods 0.000 claims description 7
- 238000007664 blowing Methods 0.000 claims description 6
- 239000011248 coating agent Substances 0.000 claims description 6
- 239000000498 cooling water Substances 0.000 claims description 6
- 239000012774 insulation material Substances 0.000 claims description 6
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 230000000087 stabilizing effect Effects 0.000 claims description 2
- 239000011247 coating layer Substances 0.000 description 14
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 10
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 7
- 238000005253 cladding Methods 0.000 description 7
- 239000000835 fiber Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000000377 silicon dioxide Substances 0.000 description 4
- 239000011347 resin Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 238000007789 sealing Methods 0.000 description 3
- 238000005452 bending Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000012681 fiber drawing Methods 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- 208000025174 PANDAS Diseases 0.000 description 1
- 208000021155 Paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection Diseases 0.000 description 1
- 240000000220 Panda oleosa Species 0.000 description 1
- 235000016496 Panda oleosa Nutrition 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000007847 structural defect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
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
- C03B37/02709—Polarisation maintaining fibres, e.g. PM, PANDA, bi-refringent optical fibres
-
- 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
- C03B37/02727—Annealing or re-heating
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2203/00—Fibre product details, e.g. structure, shape
- C03B2203/10—Internal structure or shape details
- C03B2203/22—Radial profile of refractive index, composition or softening point
- C03B2203/28—Large core fibres, e.g. with a core diameter greater than 60 micrometers
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2203/00—Fibre product details, e.g. structure, shape
- C03B2203/30—Polarisation maintaining [PM], i.e. birefringent products, e.g. with elliptical core, by use of stress rods, "PANDA" type fibres
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2205/00—Fibre drawing or extruding details
- C03B2205/56—Annealing or re-heating the drawn fibre prior to coating
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2205/00—Fibre drawing or extruding details
- C03B2205/60—Optical fibre draw furnaces
- C03B2205/62—Heating means for drawing
Abstract
The invention relates to a wire drawing device and a method for a large-core-diameter single-polarization optical fiber. The equipment is characterized by comprising a low-temperature area of the wire drawing furnace, a high-temperature area of the wire drawing furnace and an annealing pipe, wherein the low-temperature area of the wire drawing furnace and the high-temperature area of the wire drawing furnace are alternately and sequentially arranged to form a heating furnace area, the central lines of the high-temperature areas of the two wire drawing furnaces are mutually vertical to the central connecting line of the stress elements of the optical fiber, the central lines of the low-temperature areas of the two wire drawing furnaces are consistent with the central connecting line of the stress elements, and the annealing pipe is placed under. The method is characterized by comprising the steps of clamping the prefabricated rod in a wire drawing furnace; step two, heating the wire drawing furnace; step three, hanging the plate, and setting the temperature of an annealing pipe; step four, performing vacuum pumping treatment on the prefabricated rod; step five, drawing wires; and step six, cutting off the optical fiber. The invention can eliminate the uneven internal stress generated in the drawing process of the large-core-diameter single-polarization optical fiber, so that the optical fiber has the characteristic of being capable of being welded perfectly after being cut, and the usability of the optical fiber is further realized.
Description
Technical Field
The invention relates to the technical field of optical fibers, in particular to drawing equipment and a drawing method for a large-core-diameter single-polarization optical fiber.
Background
The common optical fiber is designed in a symmetrical cylindrical structure, but in practical application, the common optical fiber is subjected to mechanical stress to become asymmetrical, and a birefringence phenomenon is generated, so that the polarization state of light is irregularly changed when the light is transmitted in the common optical fiber. The main influencing factors are wavelength, bending degree, temperature and the like. The polarization maintaining fiber can solve the problem of polarization state change, and a panda type or bow-tie type stress circle is generally adopted to apply stress to the fiber core to generate stress polarization, so that the polarization maintaining fiber or the single polarization fiber is formed.
The traditional method for drawing the polarization maintaining optical fiber is to vacuumize a heated liquid stress element on the basis of a non-polarization maintaining optical fiber, so that bubbles are prevented from being mixed into the stress element. The drawing process has two main defects, namely, the shape of the prefabricated rod is not uniform everywhere due to the existence of the stress element, the heating temperature required by the part occupied by the stress element is lower than the temperature of the part vertical to the stress element, because the stress element mainly consists of boron-doped quartz with a lower melting point, and the annular heating furnace is not favorable for heating the prefabricated rod, so that the energy consumption is wasted, and the uniformity of the quartz and the stress element is optimized; secondly, in the annealing process, the residual stress in the optical fiber is not uniform due to insufficient annealing temperature and time. Optical fibers having non-uniform internal stress or structural defects may cause excessive warpage of the optical fiber and end face cracks during cleaving, thereby causing the optical fiber to lose its usability. Especially for the polarization maintaining optical fiber or single polarization optical fiber with the cladding diameter of about 400 mu m, the conventional polarization maintaining optical fiber drawing process can lead to the fact that almost 100% of the optical fiber can generate end surface cracks after being cut, thereby leading to the generation of a plurality of bubbles during welding, leading to large loss and heat generation during the transmission of dozens of watts or even lower laser power, being easy to burn, thereby bearing the power of over hundred watts, and the mechanical tensile strength and the bending resistance of the optical fiber are usually low, thus losing the usability. Therefore, a process method capable of solving the problem of uneven stress, improving the quality of the cutting surface of the optical fiber and improving the yield of the optical fiber needs to be found.
Disclosure of Invention
The invention aims to provide drawing equipment and a drawing method for a large-core-diameter single-polarization optical fiber, which can eliminate uneven stress in the optical fiber and have no defects when the large-core-diameter optical fiber is cut and welded, and the drawing equipment and the drawing method have the specific structure that:
the drawing equipment for the large-core-diameter single-polarization optical fiber is characterized in that: the optical fiber annealing furnace comprises two low-temperature areas (2) of the wire drawing furnace, two high-temperature areas (3) of the wire drawing furnace and an annealing pipe, wherein the low-temperature areas (2) of the wire drawing furnace and the high-temperature areas (3) of the wire drawing furnace are alternately and sequentially arranged to form a heating furnace area, the central lines of the high-temperature areas (3) of the wire drawing furnace and the central connecting line of a stress element (1) of an optical fiber are mutually vertical, the central lines of the low-temperature areas (2) of the wire drawing furnace and the central connecting line of the stress element (1) are consistent, and the annealing pipe is placed under the central line of the.
Further, the ratio of the arc length of the high-temperature area (3) of the wire-drawing furnace to the arc length of the low-temperature area (2) of the wire-drawing furnace is 1:2 to 2: 1.
Further, the temperature of the high-temperature zone (3) of the wire drawing furnace is 2000-2100 ℃, and the temperature of the low-temperature zone (2) of the wire drawing furnace is 1800-2000 ℃.
Further, the number of the annealing tubes can be two, three or four, the temperature is arranged from high to low, the temperature of the annealing tubes is 1000 ℃ to 100 ℃, and the length of the annealing tubes is 80cm to 150 cm.
Furthermore, the high-temperature area (3) and the low-temperature area (2) of the wire-drawing furnace are composed of a plurality of temperature-adjustable wire-drawing furnace slices according to the arc length proportion.
Further, the annealing pipe is a temperature-adjustable annealing pipe.
The invention provides a method for using the large-core-diameter single-polarization optical fiber drawing equipment, which is characterized by comprising the following steps of:
the method comprises the following steps that firstly, a single polarization optical fiber preform is placed in a wire drawing furnace in a clamping and hoisting mode, the direction of a circle center connecting line of a stress element (1) is aligned to the central axis of a low-temperature area (2) of the wire drawing furnace, and the direction of the circle center connecting line of the stress element (1) is vertical to the central axis of a high-temperature area (3) of the wire drawing furnace;
step two, heating the drawing furnace to heat the tip area of the prefabricated rod; nitrogen purging protection is adopted in the wire drawing furnace, and cooling water is adopted to carry out cooling treatment on the heat insulation material in the wire drawing furnace; setting the temperature of the wire drawing furnace to a preset temperature;
step three, hanging the disc after the conical head falls down, and setting the temperature of the annealing pipe to be a preset temperature;
step four, performing vacuum-pumping treatment on the top of the preform, and vacuumizing the hole where the stress element is located;
step five, drawing the preform, stabilizing the drawing speed from slow to fast at a preset speed, and purging and cooling the optical fiber passing through the annealing pipe by adopting helium gas in the drawing process;
and step six, cutting off the optical fiber according to the requirement, cooling the drawing furnace, and finishing drawing.
Further, in the second step, the preset temperature of the wire drawing furnace is that the temperature of the high temperature zone (3) of the wire drawing furnace is between 2000 ℃ and 2100 ℃, and the temperature of the low temperature zone (2) of the wire drawing furnace is between 1800 ℃ and 2000 ℃;
in the third step, the annealing pipe is preset at a temperature of 1000-100 ℃ and has a length of 150-80 cm.
Further, the negative pressure of the vacuum-pumping treatment in the fourth step is set to be 30Mbar to 80 Mbar;
and the drawing speed in the step five is 5m/min when starting, the corresponding rod feeding speed is about 0.8mm/min, the drawing speed is kept between 40m/min and 60m/min when the drawing speed is stable, and the blowing amount of helium is 5L/min.
Further, the inner and outer surfaces of the optical fiber can be coated and cured as required between the fifth step and the sixth step.
The invention upgrades the wire drawing furnace, changes an annular temperature zone into four temperature zones which are symmetrically distributed, and a pair of temperature zones close to the stress element can be set to have a temperature lower than that of the pair of temperature zones far away from the stress element, thereby being convenient for adjusting the viscosity of the stress element, further adjusting the cooling and curing speed and stress uniformity of the stress element, and saving energy to a certain extent due to the low-temperature setting of the temperature zone close to the stress element; meanwhile, the annealing area of the wire drawing is changed into three annealing temperature areas capable of independently controlling the temperature, so that the annealing time is prolonged, the condition that the internal stress is not uniform due to sudden temperature drop in optical fiber annealing is avoided, the quality of the cut end face of the large-core-diameter polarization maintaining optical fiber or the single-polarization optical fiber is greatly improved, for example, the number of end face cracks can be 0 or 1, and the length of the cracks is not more than one tenth of the diameter of the end face, so that the yield of the optical fiber is obviously improved, and the transmission of kilowatt-level polarization laser is realized.
Drawings
The present invention will be described in further detail with reference to the following drawings and specific examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
FIG. 1 is a schematic view of a drawing furnace and an annealing tube;
FIG. 2 is a cross-sectional view of a drawing furnace and a preform;
FIG. 3 is a longitudinal sectional view of the drawing furnace and the preform.
Description of reference numerals:
1. a stress element; 2. a low-temperature area of the wire drawing furnace; 3. a high-temperature wire drawing furnace sheet; 4. a high temperature annealing pipe; 5. annealing the tube at a medium temperature; 6. and (4) annealing the tube at a low temperature.
Detailed Description
The present invention will be described in further detail with reference to the following drawings and specific examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The drawing device of the large-core-diameter single-polarization optical fiber comprises a plurality of drawing furnace plates and a plurality of annealing pipes as shown in figure 1, wherein the drawing furnace plates surround a stress element 1 in an optical fiber preform to serve as a drawing furnace. The drawing furnace is divided into a plurality of groups of temperature areas, the temperature areas at the opposite corners are consistent, the temperature areas with different temperatures are adjacent to each other, and the drawing furnace is generally divided into 4 temperature areas, namely two drawing furnace high-temperature areas 3 and two drawing furnace low-temperature areas 2. The central point connecting line of the high-temperature area 3 of the wire drawing furnace is vertical to the central connecting line of the two stress elements 1 in the optical fiber to be processed, and the central point connecting line of the low-temperature area 2 of the wire drawing furnace is consistent with the central connecting line of the two stress elements 1 in the optical fiber to be processed.
The arc length ratio of adjacent temperature zones of a common wire drawing furnace (namely the arc length ratio of a high-temperature zone and a low-temperature zone) is 1: 2-2: 1, the temperature of the high-temperature zone is 2000-2100 ℃, and the temperature of the low-temperature zone is 1800-2000 ℃. In order to facilitate temperature adjustment, the temperature-adjustable wire drawing furnace slices can be selected to form each temperature area.
The temperatures of the annealing pipes are different and are arranged below the center line of the wire drawing furnace, and the temperatures are arranged from high to low in sequence along with the increase of the distance from the wire drawing furnace.
The number of the annealing tubes can be two to four according to the requirement, the temperature of the annealing tube with the highest temperature is 800-1000 ℃, and the temperature of the annealing tube with the lowest temperature is 100-200 ℃. The length of the annealing pipe is 80 cm-150 cm. The annealing tube with adjustable temperature can be selected for temperature adjustment.
The drawing equipment based on the large-core-diameter single-polarization optical fiber comprises the following specific drawing methods:
placing the single polarization optical fiber preform in a wire drawing furnace in a clamping and hoisting mode, wherein the direction of a circle center connecting line of a stress element 1 is aligned to the central axis of a low-temperature area of the wire drawing furnace, and the vertical direction is aligned to the central axis of a high-temperature area of the wire drawing furnace;
step two, heating the drawing furnace to about 2010 ℃, and heating an area of about 5cm of the tip of the preform; nitrogen purging protection is adopted in the wire drawing furnace, and cooling water is adopted to carry out cooling treatment on the heat insulation material in the wire drawing furnace; setting the temperature of the annealing pipe to a preset temperature;
step three, hanging the disc after the cone head falls down, and setting each temperature zone of the wire drawing furnace to 1800-2100 ℃;
step four, performing vacuum-pumping treatment on the top of the preform, and vacuumizing the hole where the stress element is located, wherein the negative pressure is set to be 30 Mbar-80 Mbar, so that gas in the hole is not mixed into the stress element to form bubbles, and the deformation of the stress element hole due to overhigh negative pressure is avoided;
and step five, drawing the prefabricated rod. For a preform rod with a rod diameter of about 30mm, the starting drawing speed is about 5m/min, and the corresponding rod feeding speed is about 0.8 mm/min. After the speed is gradually increased by rod feeding and wire drawing, the wire drawing speed is finally kept between 40m/min and 60 m/min. And in the drawing process, the optical fiber passing through the annealing pipe is blown and cooled by helium, and the blowing flow of the helium is about 5L/min. The annealing tubes consist of 2-4 tubes, the temperature is set to be 800-1000 ℃, 400-700 ℃ to 100-150 ℃ from top to bottom, and the length of a single tube is 150-80 cm.
And selecting proper coatings of the inner coating layer and the outer coating layer according to requirements for coating and curing. For double-clad optical fiber, low-refractive-index resin is adopted as the inner coating layer of the optical fiber, and high-refractive-index acrylate is selected as the material of the outer coating layer. For single-clad optical fibers, the inner coating of the optical fiber is made of high-refractive-index and low-modulus acrylate used for manufacturing conventional communication optical fibers, and the material of the outer coating is high-refractive-index acrylate. When the outer diameter of the silica cladding of the optical fiber is 400 μm, the outer diameter of the inner coating layer is about 500 μm and the outer diameter of the outer coating layer is about 550 μm.
And step six, cutting off the optical fiber according to the requirement, cooling the drawing furnace, and finishing drawing.
In order to better illustrate the present invention, the drawing method of the present invention will be further described with reference to specific examples.
Example 1: this example draws a preform having a rod diameter of 29.6mm into a double clad optical fiber.
In the implementation, the arc length ratio of the low-temperature area 2 of the wire drawing furnace to the high-temperature area 3 of the wire drawing furnace is 1:1, and the wire drawing furnace is composed of one wire drawing furnace piece with adjustable temperature. The annealing tubes consist of 2 annealing tubes, the lengths of the high-temperature annealing tube 4 and the low-temperature annealing tube 6 are respectively 80cm and 150cm, and the temperatures are respectively 800 ℃ and 100 ℃. The remaining parameters are shown in example 1 of Table 1.
Placing a single polarization optical fiber preform in a wire drawing furnace in a clamping and hoisting mode, wherein the direction of a circle center connecting line of a stress element 1 is aligned to the central axis of a low-temperature area 2 of the wire drawing furnace, and the vertical direction is aligned to the central axis of a high-temperature area 3 of the wire drawing furnace;
step two, heating the drawing furnace to 2010 ℃, and heating a 5cm area at the tip of the preform; nitrogen purging protection is adopted in the wire drawing furnace, and cooling water is adopted to carry out cooling treatment on the heat insulation material of the wire drawing furnace;
step three, hanging the disc after the cone head falls down, and setting the temperatures of a low-temperature area 2 and a high-temperature area 3 of a wire drawing furnace of the wire drawing furnace to be 1900 ℃ and 2000 ℃ respectively;
fourthly, vacuumizing the top of the prefabricated rod, sleeving an air pump at the tail end, close to the clamping end, of the prefabricated rod through a hose and a clamp with a high-temperature-resistant rubber sealing ring, vacuumizing the holes where the two stress elements are located, wherein the negative pressure is 50Mbar, so that gas in the holes cannot be mixed into the stress elements to form bubbles and the holes of the stress elements cannot deform due to the fact that the gas in the holes is prevented from being mixed into the stress elements;
and step five, continuously drawing the preform after the upper disc, wherein the starting drawing speed of the preform with the rod diameter of 29.6mm is 5m/min, and the corresponding rod feeding speed is 0.85 mm/min. After the speed is gradually increased by rod feeding and wire drawing, the wire drawing speed is finally kept at 50m/min, and the rod feeding speed is 8.0 mm/min. And (4) adopting helium to blow and cool the optical fiber passing through the annealing pipe, wherein the blowing flow of the helium is 5L/min. The annealing tubes are composed of 2 tubes, the temperatures of the self-annealing tube 4 and the annealing tube 6 are set to 800 ℃ and 100 ℃ respectively, and the lengths of the single tubes are 80cm and 150cm respectively.
Drawing a double-clad optical fiber, wherein the inner coating layer of the optical fiber adopts low-refractive-index resin with the refractive index of 1.37, the material of the outer coating layer selects KG200 acrylate, the power of an ultraviolet curing lamp is 100 watts, and the drawing tension is 100 g. The outer diameter of the silica cladding of the optical fiber was 394 μm, the outer diameter of the inner coating layer was 510 μm, and the outer diameter of the outer coating layer was 552 μm.
Example 2: this example draws a preform having a rod diameter of 28.9mm into a double clad optical fiber.
In the embodiment, the arc length ratio of the low-temperature area 2 of the wire drawing furnace to the high-temperature area 3 of the wire drawing furnace is 1:2, the low-temperature area 2 of the wire drawing furnace is formed by one wire drawing furnace piece, and the high-temperature area 3 of the wire drawing furnace is formed by placing two wire drawing furnace pieces side by side. The annealing tubes 4, 5 and 6 are 80cm, 100cm and 150cm long, respectively, and the temperature is 1000 deg.C, 700 deg.C and 200 deg.C. The remaining parameters are shown in example 2 of Table 1
Placing a single polarization optical fiber preform in a wire drawing furnace in a clamping and hoisting mode, wherein the direction of a circle center connecting line of a stress element 1 is aligned to the central axis of a low-temperature area 2 of the wire drawing furnace, and the vertical direction is aligned to the central axis of a high-temperature area 3 of the wire drawing furnace;
step two, heating the drawing furnace to 2010 ℃, and heating a 5cm area at the tip of the preform; nitrogen purging protection is adopted in the wire drawing furnace, and cooling water is adopted to carry out cooling treatment on the heat insulation material of the wire drawing furnace;
step three, hanging the disc after the cone head falls down, and setting the temperatures of a low-temperature area 2 and a high-temperature area 3 of a wire drawing furnace of the wire drawing furnace to be 1800 ℃ and 2050 ℃ respectively;
step four, vacuumizing the top of the preform, sleeving an air pump at the tail end, close to the clamping end, of the preform through a hose and a clamp with a high-temperature-resistant rubber sealing ring, vacuumizing the holes where the two stress elements are located, wherein the negative pressure is 30Mbar, so that gas in the holes cannot be mixed into the stress elements to form bubbles and the holes of the stress elements cannot deform due to the fact that the gas in the holes is prevented from being mixed into the stress elements;
and step five, continuously drawing the preform after the upper disc, wherein the starting drawing speed of the preform with the rod diameter of 28.9mm is 5m/min, and the corresponding rod feeding speed is 0.85 mm/min. After the speed is gradually increased by rod feeding and wire drawing, the wire drawing speed is finally kept at 40m/min, and the rod feeding speed is 8.2 mm/min. And (4) adopting helium to blow and cool the optical fiber passing through the annealing pipe, wherein the blowing flow of the helium is 5L/min. The annealing tubes are composed of 3 tubes, the temperatures of the self-annealing tube 4, the annealing tube 5 and the annealing tube 6 are set to 1000 ℃, 700 ℃ and 100 ℃, respectively, and the lengths of the single tubes are 80cm, 100cm and 150cm, respectively.
Drawing a double-clad optical fiber, wherein the inner coating layer of the optical fiber adopts low-refractive-index resin with the refractive index of 1.37, the material of the outer coating layer selects KG200 acrylate, the power of an ultraviolet curing lamp is 100 watts, and the drawing tension is 100 g. The silica cladding of the optical fiber had an outer diameter of 399 μm, the inner cladding had an outer diameter of 502 μm, and the outer cladding had an outer diameter of 555 μm.
Example 3: this example draws a preform having a rod diameter of 30.1mm into a single clad optical fiber.
In the embodiment, the arc length ratio of the low-temperature area 2 of the wire drawing furnace to the high-temperature area 3 of the wire drawing furnace is 2:1, the low-temperature area 2 of the wire drawing furnace is formed by placing two wire drawing furnace sheets side by side, and the high-temperature area 3 of the wire drawing furnace is formed by two wire drawing furnace sheets. The annealing tubes are composed of 4 annealing tubes, the lengths of the annealing tubes 4, 5, 6 and 6 are respectively 80cm, 100cm, 150cm and 150cm, and the temperatures are respectively 1000 ℃, 700 ℃, 400 ℃ and 100 ℃. The remaining parameters are shown in example 3 of Table 1.
Placing a single polarization optical fiber preform in a wire drawing furnace in a clamping and hoisting mode, wherein the direction of a circle center connecting line of a stress element 1 is aligned to the central axis of a low-temperature area 2 of the wire drawing furnace, and the vertical direction is aligned to the central axis of a high-temperature area 3 of the wire drawing furnace;
step two, heating the drawing furnace to 2010 ℃, and heating a 5cm area at the tip of the preform; nitrogen purging protection is adopted in the wire drawing furnace, and cooling water is adopted to carry out cooling treatment on the heat insulation material of the wire drawing furnace;
step three, hanging the disc after the cone head falls down, and setting the temperatures of a low-temperature area 2 and a high-temperature area 3 of a wire drawing furnace of the wire drawing furnace to 2000 ℃ and 2100 ℃ respectively;
step four, vacuumizing the top of the preform, sleeving an air pump at the tail end, close to the clamping end, of the preform through a hose and a clamp with a high-temperature-resistant rubber sealing ring, vacuumizing the holes where the two stress elements are located, wherein the negative pressure is 80Mbar, so that gas in the holes cannot be mixed into the stress elements to form bubbles and the holes of the stress elements cannot deform due to the fact that the gas in the holes is mixed into the stress elements;
and step five, continuously drawing the preform after the upper disc, wherein the starting drawing speed of the preform with the rod diameter of 30.1mm is 5m/min, and the corresponding rod feeding speed is 0.81 mm/min. After the speed is gradually increased by rod feeding and wire drawing, the wire drawing speed is finally kept at 60m/min, and the rod feeding speed is 8.1 mm/min. And (4) adopting helium to blow and cool the optical fiber passing through the annealing pipe, wherein the blowing flow of the helium is 5L/min. The annealing tubes are 4, the lengths of the high-temperature annealing tube 4, the annealing tube 5, the annealing tube 6 and the annealing tubes below the annealing tubes are respectively 80cm, 100cm, 150cm and 150cm, and the temperatures are respectively 1000 ℃, 700 ℃, 400 ℃ and 100 ℃.
The single-clad optical fiber is drawn, the inner coating layer of the optical fiber adopts FeykKG 100 acrylate, the material of the outer coating layer selects KG200 acrylate, the power of an ultraviolet curing lamp is 100 watts, and the drawing tension is 100 g. The outer diameter of the silica cladding of the optical fiber was 392 μm, the outer diameter of the inner coating was 490 μm and the outer diameter of the outer coating was 548 μm.
In order to better illustrate the three embodiments of the present invention, the design parameters of the apparatus and the process parameters during drawing are shown in table 1.
TABLE 1 drawing parameters of large core diameter single polarization fiber
The optical fibers manufactured by the three embodiments are tested by the invention, and the test data are shown in table 2.
TABLE 2 Main Properties of the optical fibers of the three examples
The data of the table 2 can be obtained, the wire drawing furnace is upgraded, the annular temperature zone is changed into four temperature zones (furnace plates) which are symmetrically distributed, and the temperature of the temperature zone pair close to the stress element can be set to be lower than that of the temperature zone pair far away from the stress element, so that the viscosity of the stress element can be conveniently adjusted, the cooling and curing speed and the stress uniformity of the stress element can be adjusted, and the energy can be saved to a certain extent due to the low-temperature setting of the temperature zone close to the stress element; the low-temperature setting of the temperature area close to the stress element can save energy to a certain extent, so that the uneven internal stress generated in the wire drawing process of processing the large-core single-polarization optical fiber or the polarization maintaining optical fiber is effectively reduced or even eliminated; meanwhile, the annealing area of the drawn wire is changed into a plurality of annealing temperature areas capable of independently controlling the temperature, so that the annealing time is prolonged, the condition that the internal stress is not uniform due to the sudden temperature drop in the annealing of the optical fiber is avoided, the quality of the cut end face of the large-core-diameter polarization maintaining optical fiber or the single-polarization optical fiber is greatly improved, for example, the number of end face cracks can be 0 or 1, and the length of the cracks does not exceed one tenth of the diameter of the end face, so that the optical fiber has the characteristic of being welded well after being cut, the availability of the optical fiber is further realized, the possibility of outputting high-power polarization laser is provided, and the optical fiber can be widely used for laser.
The present invention is not limited to the above embodiments, and those skilled in the art can implement the present invention in other various embodiments according to the present disclosure, since the scope of the present invention is defined by the appended claims.
Claims (10)
1. The drawing equipment for the large-core-diameter single-polarization optical fiber is characterized in that: the optical fiber annealing furnace comprises two low-temperature areas (2) of the wire drawing furnace, two high-temperature areas (3) of the wire drawing furnace and an annealing pipe, wherein the low-temperature areas (2) of the wire drawing furnace and the high-temperature areas (3) of the wire drawing furnace are alternately and sequentially arranged to form a heating furnace area, the central lines of the high-temperature areas (3) of the wire drawing furnace and the central connecting line of a stress element (1) of an optical fiber are mutually vertical, the central lines of the low-temperature areas (2) of the wire drawing furnace and the central connecting line of the stress element (1) are consistent, and the annealing pipe is placed under the central line of the.
2. The apparatus for drawing a large core single polarization optical fiber according to claim 1, wherein: the ratio of the arc length of the high-temperature area (3) of the wire-drawing furnace to the arc length of the low-temperature area (2) of the wire-drawing furnace is 1:2 to 2: 1.
3. The apparatus for drawing a large-core single-polarization optical fiber according to claim 1 or 2, wherein: the high-temperature area (3) and the low-temperature area (2) of the wire-drawing furnace are composed of a plurality of temperature-adjustable wire-drawing furnace slices according to the arc length proportion.
4. The apparatus for drawing a large core single polarization optical fiber according to claim 3, wherein: the temperature of the high-temperature zone (3) of the wire drawing furnace is 2000-2100 ℃, and the temperature of the low-temperature zone (2) of the wire drawing furnace is 1800-2000 ℃.
5. The apparatus for drawing a large-core single-polarization optical fiber according to claim 1 or 4, wherein: the annealing pipe is a temperature-adjustable annealing pipe.
6. The apparatus for drawing a large-core single-polarization optical fiber according to claim 5, wherein: the number of the annealing tubes can be two, three or four, the temperature is arranged from high to low, the temperature of the annealing tubes is 1000-100 ℃, and the length of the annealing tubes is 80-150 cm.
7. A method of drawing an optical fiber using the drawing apparatus for a large core single polarization optical fiber according to claims 1 to 6, characterized in that:
the method comprises the following steps that firstly, a single polarization optical fiber preform is placed in a wire drawing furnace in a clamping and hoisting mode, the direction of a circle center connecting line of a stress element (1) is aligned to the central axis of a low-temperature area (2) of the wire drawing furnace, and the direction of the circle center connecting line of the stress element (1) is vertical to the central axis of a high-temperature area (3) of the wire drawing furnace;
step two, heating the drawing furnace to heat the tip area of the prefabricated rod; nitrogen purging protection is adopted in the wire drawing furnace, and cooling water is adopted to carry out cooling treatment on the heat insulation material in the wire drawing furnace; setting the temperature of the wire drawing furnace to a preset temperature;
step three, hanging the disc after the conical head falls down, and setting the temperature of the annealing pipe to be a preset temperature;
step four, performing vacuum-pumping treatment on the top of the preform, and vacuumizing the hole where the stress element is located;
step five, drawing the preform, stabilizing the drawing speed from slow to fast at a preset speed, and purging and cooling the optical fiber passing through the annealing pipe by adopting helium gas in the drawing process;
and step six, cutting off the optical fiber according to the requirement, cooling the drawing furnace, and finishing drawing.
8. The method of claim 7, wherein the step of drawing the large-core single-polarization optical fiber comprises: in the second step, the preset temperature of the wire-drawing furnace is that the temperature of the high-temperature area (3) of the wire-drawing furnace is between 2000 ℃ and 2100 ℃, and the temperature of the low-temperature area (2) of the wire-drawing furnace is between 1800 ℃ and 2000 ℃;
in the third step, the annealing pipe is preset at a temperature of 1000-100 ℃ and has a length of 150-80 cm.
9. The method of claim 7, wherein the step of drawing the large-core single-polarization optical fiber comprises: the negative pressure of the vacuum-pumping treatment in the fourth step is set to be 30Mbar to 80 Mbar;
and the drawing speed in the step five is 5m/min when starting, the corresponding rod feeding speed is about 0.8mm/min, the drawing speed is kept between 40m/min and 60m/min when the drawing speed is stable, and the blowing amount of helium is 5L/min.
10. The method of claim 7, wherein: and coating and curing the inner and outer surfaces of the optical fiber between the fifth step and the sixth step.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010696199.1A CN111704357A (en) | 2020-07-20 | 2020-07-20 | Drawing equipment and method for large-core-diameter single-polarization optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010696199.1A CN111704357A (en) | 2020-07-20 | 2020-07-20 | Drawing equipment and method for large-core-diameter single-polarization optical fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111704357A true CN111704357A (en) | 2020-09-25 |
Family
ID=72546649
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010696199.1A Pending CN111704357A (en) | 2020-07-20 | 2020-07-20 | Drawing equipment and method for large-core-diameter single-polarization optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111704357A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114349328A (en) * | 2022-01-18 | 2022-04-15 | 江苏亨通光导新材料有限公司 | Simple section structure polarization maintaining parent metal and efficient preparation method thereof |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5684333A (en) * | 1979-10-29 | 1981-07-09 | Int Standard Electric Corp | Single mode optical fiber |
| US5152818A (en) * | 1990-11-09 | 1992-10-06 | Corning Incorporated | Method of making polarization retaining fiber |
| CN1083449A (en) * | 1992-08-03 | 1994-03-09 | 美国电话电报公司 | Comprise fiber optic articles with low polarization mode dispersion and the method for making this optical fiber |
| CN1210985A (en) * | 1997-09-11 | 1999-03-17 | 株式会社藤仓 | Fibre-optical raster and its producing method |
| CN1320222A (en) * | 1998-09-25 | 2001-10-31 | 康宁股份有限公司 | Optical fiber having expande dmode field diameter and method of expanding the mode field diameter of optical fiber |
| US6701046B1 (en) * | 1999-09-30 | 2004-03-02 | Corning O.T.I. Spa | Method for producing an optical coupler for extracting a signal from a polarization maintaining optical fiber, and corresponding coupler |
| JP2004224587A (en) * | 2003-01-20 | 2004-08-12 | Sumitomo Electric Ind Ltd | Drawing method and drawing apparatus for optical fiber preform |
| CN101367608A (en) * | 2008-10-14 | 2009-02-18 | 长飞光纤光缆有限公司 | Method for manufacturing panda type polarization-preserving fiber |
| CN102010123A (en) * | 2010-10-13 | 2011-04-13 | 长飞光纤光缆有限公司 | Optical fiber eat treatment method and device |
| CN102838275A (en) * | 2012-08-28 | 2012-12-26 | 长飞光纤光缆有限公司 | Wiredrawing method and wiredrawing device for outer diameter fluctuation optical fiber perform |
| WO2016099976A1 (en) * | 2014-12-15 | 2016-06-23 | Intuitive Surgical Operations, Inc. | Dissimilar cores in multicore optical fiber for strain and temperature separation |
| CN106019465A (en) * | 2016-06-01 | 2016-10-12 | 中天科技光纤有限公司 | Ultralow loss optical fiber production system and technology used for production |
| CN212982788U (en) * | 2020-07-20 | 2021-04-16 | 上海传输线研究所（中国电子科技集团公司第二十三研究所） | Wire drawing equipment for large-core-diameter single-polarization optical fiber |
-
2020
- 2020-07-20 CN CN202010696199.1A patent/CN111704357A/en active Pending
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5684333A (en) * | 1979-10-29 | 1981-07-09 | Int Standard Electric Corp | Single mode optical fiber |
| US5152818A (en) * | 1990-11-09 | 1992-10-06 | Corning Incorporated | Method of making polarization retaining fiber |
| CN1083449A (en) * | 1992-08-03 | 1994-03-09 | 美国电话电报公司 | Comprise fiber optic articles with low polarization mode dispersion and the method for making this optical fiber |
| CN1210985A (en) * | 1997-09-11 | 1999-03-17 | 株式会社藤仓 | Fibre-optical raster and its producing method |
| CN1320222A (en) * | 1998-09-25 | 2001-10-31 | 康宁股份有限公司 | Optical fiber having expande dmode field diameter and method of expanding the mode field diameter of optical fiber |
| US6701046B1 (en) * | 1999-09-30 | 2004-03-02 | Corning O.T.I. Spa | Method for producing an optical coupler for extracting a signal from a polarization maintaining optical fiber, and corresponding coupler |
| JP2004224587A (en) * | 2003-01-20 | 2004-08-12 | Sumitomo Electric Ind Ltd | Drawing method and drawing apparatus for optical fiber preform |
| CN101367608A (en) * | 2008-10-14 | 2009-02-18 | 长飞光纤光缆有限公司 | Method for manufacturing panda type polarization-preserving fiber |
| CN102010123A (en) * | 2010-10-13 | 2011-04-13 | 长飞光纤光缆有限公司 | Optical fiber eat treatment method and device |
| CN102838275A (en) * | 2012-08-28 | 2012-12-26 | 长飞光纤光缆有限公司 | Wiredrawing method and wiredrawing device for outer diameter fluctuation optical fiber perform |
| WO2016099976A1 (en) * | 2014-12-15 | 2016-06-23 | Intuitive Surgical Operations, Inc. | Dissimilar cores in multicore optical fiber for strain and temperature separation |
| CN106019465A (en) * | 2016-06-01 | 2016-10-12 | 中天科技光纤有限公司 | Ultralow loss optical fiber production system and technology used for production |
| CN212982788U (en) * | 2020-07-20 | 2021-04-16 | 上海传输线研究所（中国电子科技集团公司第二十三研究所） | Wire drawing equipment for large-core-diameter single-polarization optical fiber |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114349328A (en) * | 2022-01-18 | 2022-04-15 | 江苏亨通光导新材料有限公司 | Simple section structure polarization maintaining parent metal and efficient preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5074427B2 (en) | How to enable dual pressure control in fiber preforms during fiber production | |
| WO2022247102A1 (en) | Optical fiber drawing furnace, optical fiber preparation apparatus, optical fiber preparation method, and small-diameter optical fiber | |
| CN110794509A (en) | Single-mode optical fiber and preparation method thereof | |
| CN212982788U (en) | Wire drawing equipment for large-core-diameter single-polarization optical fiber | |
| CN111704357A (en) | Drawing equipment and method for large-core-diameter single-polarization optical fiber | |
| JP5949016B2 (en) | Optical fiber manufacturing method | |
| CN102898021B (en) | Optical fiber drawing methods and drawing furnaces | |
| CN111186999A (en) | Vacuum wire drawing furnace for manufacturing optical fiber | |
| JP5766157B2 (en) | Drawing method of glass base material | |
| KR102318786B1 (en) | High-strength welding process for making heavy glass preforms with large cross sectional areas | |
| JP7061628B2 (en) | Photonic crystal fiber and its manufacturing method | |
| CN104345388B (en) | A kind of large core fiber coupler and preparation method thereof | |
| CN107311445B (en) | Polarization maintaining optical fiber preform | |
| CN111308611B (en) | Fluorine-doped tapered sleeve and application thereof | |
| CN115710084A (en) | Glass plate directional stretching device and stretching method | |
| CN211896679U (en) | Vacuum wire drawing furnace for manufacturing optical fiber | |
| EP1165451B1 (en) | Method and apparatus for the thermal treatment of an object such as an optical fiber preform | |
| JP2012082092A (en) | Method and apparatus for manufacturing multicore tape fiber strand | |
| CN101289272A (en) | Production method of profiled silex glass holding bar and apparatus | |
| KR20020081325A (en) | Rod-shaped preform for manufacturing an optical fibre and methods of producing the preform and the fibre | |
| CN111470771A (en) | Optical fiber wire drawing annealing extension tube based on temperature cavity division principle | |
| CN218202569U (en) | Gradual change optical fiber manufacturing system | |
| CN112408773B (en) | D-shaped photonic crystal optical fiber preform and D-shaped photonic crystal optical fiber drawing method thereof | |
| CN115490420B (en) | Capillary manufacturing process for simultaneously processing multiple horn mouths | |
| CN114924345B (en) | Inner hexagonal capillary tube, manufacturing method thereof and application of inner hexagonal capillary tube in multi-core space division multiplexer |
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 |