CN2928841Y - Combined device for producing optic fiber of large size low water peak optic fiber prefabricated stick - Google Patents
Combined device for producing optic fiber of large size low water peak optic fiber prefabricated stick Download PDFInfo
- Publication number
- CN2928841Y CN2928841Y CNU2006201052381U CN200620105238U CN2928841Y CN 2928841 Y CN2928841 Y CN 2928841Y CN U2006201052381 U CNU2006201052381 U CN U2006201052381U CN 200620105238 U CN200620105238 U CN 200620105238U CN 2928841 Y CN2928841 Y CN 2928841Y
- Authority
- CN
- China
- Prior art keywords
- plug
- optical fiber
- sleeve pipe
- mandrel
- low water
- 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.)
- Expired - Lifetime
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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
- C03B37/01205—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments
- C03B37/01211—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments by inserting one or more rods or tubes into a tube
-
- 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
- C03B37/01205—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments
- C03B37/01225—Means for changing or stabilising the shape, e.g. diameter, of tubes or rods in general, e.g. collapsing
- C03B37/01228—Removal of preform material
- C03B37/01231—Removal of preform material to form a longitudinal hole, e.g. by drilling
-
- 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
- C03B37/02754—Solid fibres drawn from hollow preforms
-
- 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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- Engineering & Computer Science (AREA)
- 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
An assembled apparatus of a large-size low water peak optical fiber preform rod for optical fiber manufacture comprises a mandrel and an annular tube, and is technically characterized in that one end of the mandrel is a seed rod, which has the same structure and size as the end rod of a wiredrawing general optical fiber preform rod, the other end of the mandrel is a highly axial-symmetric cone, one end of the annular tube is a highly axial-symmetric cone with the inner pyramidal face of the conical end tightly engaged and connected with the external surface of the conical end of the mandrel, and the annular tube and the mandrel are locked and combined together by an expansion plug. Because the expansion plug can be used repeatedly and VAD mandrel is elaboration-free which means the mandrel has own accurate symmetrical conical end, the method of the utility model simplifies RIC procedure and the device for optical fiber on-line wire drawing, simultaneously improves concentricity of core cladding for optical fiber preparing with RIC method. The utility model is capable of substantially increasing productivity after making marginal reconstruction to the prior device and simultaneously reducing manufacture cost of optical fiber markedly.
Description
Technical field:
The utility model relates to a kind of device of preformod of optical fiber with low water peak in large size drawing optical fiber.
Background technology:
Since second half year calendar year 2001, the competition of optical fiber industry grows in intensity, the price of preform, optical fiber and optical cable is also kept falling, and the cost competition becomes the primary factor of the sector market competition gradually, and the cost that therefore how to reduce product also becomes the focus that each major company pays close attention to.
Studies show that, increase the size of preform, but also promptly improve the cost that the length of string of single prefabricated rods can very effective reduction unit length optical fiber.For example, pressing 100 yuan/core of optical fiber kilometer calculates, the size of prefabricated rods is increased to 80mm by 60mm, then every core kilometer can be saved 6.7 yuan of prefabricated rods starting material, ending 0.95 yuan of bar material, drawing optical fibers stay 2.92 yuan of tail materials, fine 2.84 yuan of wire drawing transition, adding up to reduces cost reaches 13.41 yuan, also promptly saves cost 13.4%.Therefore, the maximization of prefabricated rods size becomes each company and reduces the optical fiber cost, improves the inevitable choice of the market competitiveness.Plug+sleeve pipe (RIC, Rod in thecylinder) technology is considered to less investment, instant effect and can makes full use of one of optimal selection of existing installation.
In the RIC method, at first that quartz socket tube is fixing on fiber drawing furnace, the plug of coaxial again insertion preform, and then with quartz socket tube thermoplastic and molten being reduced on the plug, thereby obtain the bigger prefabricated rods of size.The quartz socket tube that uses mainly adopts the OVD manufactured at present, has higher geometric accuracy.For making single prefabricated stick drawn wire surpass 1000km, need telescopic weight 25kg at least, the cover external diameter of pipe is not less than 120mm usually, and the diameter of mandrel that is complementary with it is not less than 33mm.Method (MCVD and PCVD) prepares in the pipe and plug adopts usually, owing to be subjected to the restriction of substrate dimension, its size is often too little, this plug is directly inserted wire drawing in the sleeve pipe, the excessive clearance between plug and the sleeve pipe then, parameters such as the core concentricity of optical fiber, covering circularity can't be guaranteed.For addressing this problem, United States Patent (USP) 09/515,227,2005/0064188A1 and 6,460,378B1 have introduced increases one or more telescopic methods between plug and outer tube, to reduce the gap between plug and the sleeve pipe.But this kind method has increased stationary installation, the waste thermal source, and make clean and drying process more difficult, the difficult quality of optical fiber is controlled.U.S. Pat 2004/0107735A1, US6 for this reason, 553,790B1, European patent EP 1156018A1 adopts different technology that plug is carried out " compression " to increase the size of plug respectively with Chinese patent 200310102706.0,03124114.X, its main thought is that the less plug of size that at first deposition in the many pipes is obtained is welded together the plug that forms than long, again this long plug heating is made it softening, and then exert pressure at two ends make it to shorten, chap, thereby obtain the bigger plug of external diameter that is complementary with the large size sleeve pipe.But these compression process have all increased the manufacturing process of preform, make the quality control of optical fiber complicated more, and have increased the cost of optical fiber to a certain extent.Chinese patent 200510019304.3 and 200510019135.3 has been introduced a kind of improved " compression " technology, this method will be originally independently the plug compression section change into and in drawing process, carrying out, its juche idea is, in drawing process, plug and sleeve pipe are not fixed together, but adopt different fixing and feeding units respectively, by the relative input speed of accurate control plug with telescopic, the speed that makes plug is in proportion greater than telescopic speed, thereby reaches the equal effect of compressing plug in advance.But this method has increased by a cover stringy fixes and running gear, and very high to the accuracy requirement of plug and sleeve pipe relative movement, thereby makes the control ratio of optical fiber quality more difficult.On the other hand, for guaranteeing plug enough amounts are arranged, need at least 4 common plugs to be welded together usually, this has not only increased the excellent operation of system, and long plug often makes existing wire-drawing equipment spatially be difficult to meet the demands.
Pipe external sediment method (VAD and OVD) is not subjected to the restriction of bushing pipe, can directly make the large size plug that is complementary with sleeve pipe.Compare with OVD, VAD is more accurate to the control of plug section and geometrical dimension, though its sedimentation effect is relatively low, but when sedimentary diameter was big, its sedimentation effect can be significantly improved, and VAD technology is very easy to the control at water peak, be particularly suitable for producing preformod of optical fiber with low water peak and plug thereof, therefore, adopt VAD technology that plug is provided, and employing RIC technology production optical fiber will be a kind of low-water-peak fiber manufacture method rationally efficient, with low cost.In addition, also be easy to generate the problem of core concentricity in the RIC method, because there is big gap between plug and the sleeve pipe, this makes plug depart from the center easily after inserting sleeve pipe, to draw the core concentricity obtain optical fiber relatively poor thereby make, and cause the PMD value of optical fiber higher.For addressing this problem, U.S. Pat 2004/0107735A1 has described a kind of method that increases a chuck at sleeve bottom, though this method can be well fixing in sleeve pipe with plug, but the quartzy chuck that is increased in the sleeve pipe lower end must be melted in wire drawing and be drawn into useless transitional fibre and scrap, this has not only wasted material, and increased making and the operation of end connector down is installed, thereby also increased the production cost of optical fiber.
Summary of the invention:
The purpose of this utility model is to overcome above deficiency and provides a kind of less investment, instant effect also can make full use of the reasonable associated plant of preformod of optical fiber with low water peak in large size drawing optical fiber efficiently of existing installation.
The utility model is achieved by the following technical solution: this associated plant, comprise plug, sleeve pipe, its major technique feature is that this plug one end is kind of a rod, the ending rod during with the ordinary optic fibre prefabricated stick drawn wire is identical with size for the structure of kind of rod, and the other end of plug is the symmetric cone of altitude axis; Telescopic one end becomes the symmetric taper of altitude axis, and the intimate cooperation of the inner conical surface of conical ends and plug conical ends contacts; Expanding stopple is locked sleeve pipe and plug and is integral; The external diameter of plug is not less than 55mm, length is not less than 700mm, and the sleeve pipe of the geometrical dimension of plug and employing is complementary; Expanding stopple between described plug and the sleeve pipe is to be used to connect plug and telescopic stopper, comprises outer plug, interior plug, compact heap and venting hole; Expanding stopple is the cylinder stopcock of a hollow, and cylinder is connected and composed by the outer plug and the interior plug conical surface, and cylinder stopcock top is provided with compact heap, and a side of interior plug is provided with venting hole; Described sleeve pipe is provided with transition conduit.
The plug size need not more greatly to renew in advance in the utility model, and plug and sleeve pipe relative fixed only need to use a cover feeding unit charging wire drawing, and plug and telescopic concentricity can be controlled by the accurate processing of expanding stopple central hole location and sleeve pipe conical ends.Because this expanding stopple can use repeatedly, the VAD plug need not processing and promptly carries accurate symmetric conical ends, therefore this method has been simplified RIC operation and the online stringy device of optical fiber, improved the core concentricity that the RIC legal system is equipped with optical fiber simultaneously, existing installation is carried out a spot of transformation can increase substantially production capacity, and significantly reduce the manufacturing cost of optical fiber simultaneously.
Description of drawings:
Fig. 1 is the sectional view of the utility model middle sleeve;
Fig. 2 a is the longitudinal profile synoptic diagram of plug in the utility model;
Fig. 2 b is the cross sectional representation of plug in the utility model;
Fig. 3 passes through the longitudinal profile synoptic diagram after the transition conduit in end face processing and the welding for sleeve pipe;
Fig. 4 is the diagrammatic cross-section of expanding stopple of the present utility model;
Fig. 5 is that sleeve pipe of the present utility model and plug are loaded in the view before the wire drawing on the wire-drawer-tower;
Fig. 6 is a drawing process synoptic diagram of the present utility model.
Embodiment:
For convenience of description, relational language and parameter are done following explanation:
Shown in Fig. 2 a, 2b, plug 20: the stuffed quartz rod that adopts VAD technology to make comprises the sandwich layer 22 and the pure SiO that mix Ge
2Covering 23;
As Fig. 1, shown in Figure 3, sleeve pipe 10: the cylindric purity quartz glass pipe for high 11 of high geometric accuracy;
Expanding stopple 30 as shown in Figure 4: be used to connect plug and telescopic stopper, mainly comprise overcoat 31, interior plug 32, compact heap 33 and venting hole 34; Expanding stopple is the cylinder stopcock of a hollow, and cylinder is connected and composed by the outer plug and the interior plug conical surface, and cylinder stopcock top is provided with compact heap, and a side of interior plug is provided with venting hole.
R
r: plug Bao Xin ratio, the i.e. ratio of the diameter t of plug and plug center core layer diameter a;
D
o: the telescopic external diameter;
D
i: the telescopic internal diameter;
D
v: the green diameter of the plug that the VAD prepared obtains;
D
r: through extending the diameter of back plug;
L
c: telescopic length;
L
v: the plug length that the VAD prepared obtains without extension;
L
r: through extending the length of back plug
R
f: the Bao Xin ratio of optical fiber, the i.e. ratio of the external diameter of bare fibre and optical fiber center core layer diameter.
The preparation of plug
Before the plug preparation, at first to calculate the external diameter of required plug 20 according to internal diameter, external diameter and the length dimension of sleeve pipe 10, the length value of plug is not less than the telescopic length value.Method of calculation are as follows:
Then, according to D
rValue and telescopic length adopt VAD explained hereafter plug and extend to special diameter and length, with D
rPlug green diameter that matches and length relation satisfy formula (2).Plug one end of VAD technology gained is kind of a rod 21, its structure with geometrical dimension during with wire drawing the ending rod of prefabricated rods identical, be used as the ending rod of plug, the other end of plug then is the fabulous cone of axial symmetry 24.
The processing of the sleeve pipe conical surface
On the flour milling processing machine telescopic one end is worn into frustum 12, the high h of cone is 60mm usually, and tapering is 40 degree.
Sleeve pipe awl end internal diameter shrinks and the transition conduit welding
Heating is shunk the internal diameter of sleeve pipe awl end on flame, and usually, the least significant end inside diameter Ds of shrinking posterior pyramids is no more than 1/2 of corresponding diameter of mandrel.On flame, be L again with length
t(as 250mm), inside diameter D
TiAnd outer diameter D
To Transition silica tube 13 weldings that match with sleeve pipe are at the telescopic the other end.All flame machining are limit heating edge Rotating with Uniform body all.
As Fig. 5, shown in Figure 6, the sleeve pipe wire drawing
At first, be loaded in the fiber drawing furnace 40 with the sleeve pipe that connects transition conduit, the anchor clamps on the wire-drawer-tower 41 are fixed on the transition conduit 13 processing frustum; Secondly, plug is inserted in the sleeve pipe, the cone of plug one end is inserted in the frustum of sleeve pipe lower end, allow the male cone (strobilus masculinus) of plug cone segments and the inner conical surface of sleeve pipe frustum end combine closely; Then, expanding stopple 30 is installed on the kind rod 21 of the plug the other end and is filled in the telescopic transition conduit 13,, sleeve pipe and plug are fixed together expanding stopple locking; Feeding fluorine-containing gas (as SF6) and assist gas (as He) again in sleeve pipe cleans to surface clean the surface and the telescopic internal surface of plug; Close purge gas, and connect vacuum pump, the furnace temperature to 2000 that raises simultaneously～2200 ℃ make softening melting zone 14 and 25 and be drawn into optical fiber 50 of forming in sleeve pipe and plug bottom.During wire drawing, sleeve pipe and plug are fixed together all the time, and also feeding synchronously of plug when the sleeve pipe feeding is till sleeve pipe has drawn.
Claims (4)
1, a kind of preformod of optical fiber with low water peak in large size is made the associated plant of optical fiber, comprise plug, sleeve pipe is characterized in that this plug one end is kind of a rod, the ending rod during with the ordinary optic fibre prefabricated stick drawn wire is identical with size for the structure of kind of rod, and the other end of plug is the symmetric cone of altitude axis; Telescopic one end becomes the symmetric taper of altitude axis, and the intimate cooperation of the inner conical surface of conical ends and plug conical ends contacts; Expanding stopple is locked sleeve pipe and plug and is integral.
2, a kind of preformod of optical fiber with low water peak in large size as claimed in claim 1 is made the associated plant of optical fiber, it is characterized in that the external diameter of plug is not less than 55mm, length is not less than 700mm, and the sleeve pipe of the geometrical dimension of plug and employing is complementary.
3, a kind of preformod of optical fiber with low water peak in large size as claimed in claim 1 is made the associated plant of optical fiber, it is characterized in that the expanding stopple between described plug and the sleeve pipe is to be used to connect plug and telescopic stopper, comprise outer plug (31), interior plug (32), compact heap (33) and venting hole (34); Expanding stopple is the cylinder stopcock of a hollow, and cylinder is connected and composed by the outer plug and the interior plug conical surface, and cylinder stopcock top is provided with compact heap, and a side of interior plug is provided with venting hole.
4, a kind of preformod of optical fiber with low water peak in large size as claimed in claim 1 is made the associated plant of optical fiber, it is characterized in that described sleeve pipe is provided with transition conduit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2006201052381U CN2928841Y (en) | 2006-06-30 | 2006-06-30 | Combined device for producing optic fiber of large size low water peak optic fiber prefabricated stick |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2006201052381U CN2928841Y (en) | 2006-06-30 | 2006-06-30 | Combined device for producing optic fiber of large size low water peak optic fiber prefabricated stick |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2928841Y true CN2928841Y (en) | 2007-08-01 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2006201052381U Expired - Lifetime CN2928841Y (en) | 2006-06-30 | 2006-06-30 | Combined device for producing optic fiber of large size low water peak optic fiber prefabricated stick |
Country Status (1)
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|---|---|
| CN (1) | CN2928841Y (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103936277A (en) * | 2014-03-20 | 2014-07-23 | 富通集团有限公司 | Multi-core optical fiber manufacturing method |
| CN106007353A (en) * | 2016-05-19 | 2016-10-12 | 江苏亨通光导新材料有限公司 | Fixing device of optical fiber preform and fixing method of fixing device |
| CN107512848A (en) * | 2017-09-30 | 2017-12-26 | 长飞光纤潜江有限公司 | A kind of sintering equipment and method of the loose powder rod of large-scale optical fiber |
| CN111362571A (en) * | 2019-12-30 | 2020-07-03 | 中天科技精密材料有限公司 | Optical fiber, optical fiber preform and method of manufacturing |
| CN112880595A (en) * | 2021-03-03 | 2021-06-01 | 华能(泰安)光电科技有限公司 | Device and method for automatically detecting concentricity of optical fiber preform core package |
| CN113387558A (en) * | 2021-06-30 | 2021-09-14 | 杭州富通通信技术股份有限公司 | Processing technology of prefabricated rod |
| CN116143397A (en) * | 2023-03-29 | 2023-05-23 | 武汉睿芯特种光纤有限责任公司 | Preparation method of tapered optical fiber and tapered optical fiber |
-
2006
- 2006-06-30 CN CNU2006201052381U patent/CN2928841Y/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103936277A (en) * | 2014-03-20 | 2014-07-23 | 富通集团有限公司 | Multi-core optical fiber manufacturing method |
| CN106007353A (en) * | 2016-05-19 | 2016-10-12 | 江苏亨通光导新材料有限公司 | Fixing device of optical fiber preform and fixing method of fixing device |
| CN107512848A (en) * | 2017-09-30 | 2017-12-26 | 长飞光纤潜江有限公司 | A kind of sintering equipment and method of the loose powder rod of large-scale optical fiber |
| CN107512848B (en) * | 2017-09-30 | 2023-03-21 | 长飞光纤潜江有限公司 | Sintering device and method for large-size optical fiber loose powder rod |
| CN111362571A (en) * | 2019-12-30 | 2020-07-03 | 中天科技精密材料有限公司 | Optical fiber, optical fiber preform and method of manufacturing |
| CN112880595A (en) * | 2021-03-03 | 2021-06-01 | 华能(泰安)光电科技有限公司 | Device and method for automatically detecting concentricity of optical fiber preform core package |
| CN113387558A (en) * | 2021-06-30 | 2021-09-14 | 杭州富通通信技术股份有限公司 | Processing technology of prefabricated rod |
| CN113387558B (en) * | 2021-06-30 | 2022-09-23 | 杭州富通通信技术股份有限公司 | Processing technology of preform |
| CN116143397A (en) * | 2023-03-29 | 2023-05-23 | 武汉睿芯特种光纤有限责任公司 | Preparation method of tapered optical fiber and tapered optical fiber |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20070801 |
|
| EXPY | Termination of patent right or utility model |