CN103043894A - Holding furnace of optical fiber preform deposition lathe for plasma chemistry vapor deposition (PCVD) processing - Google Patents

Holding furnace of optical fiber preform deposition lathe for plasma chemistry vapor deposition (PCVD) processing Download PDF

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Publication number
CN103043894A
CN103043894A CN2012104892812A CN201210489281A CN103043894A CN 103043894 A CN103043894 A CN 103043894A CN 2012104892812 A CN2012104892812 A CN 2012104892812A CN 201210489281 A CN201210489281 A CN 201210489281A CN 103043894 A CN103043894 A CN 103043894A
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China
Prior art keywords
furnace
holding furnace
thermal
chamber
temperature
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CN2012104892812A
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CN103043894B (en
Inventor
朱继红
龙胜亚
王瑞春
刘涛
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Yangtze Optical Fibre and Cable Co Ltd
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Yangtze Optical Fibre and Cable Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01Manufacture of glass fibres or filaments
    • C03B37/012Manufacture of preforms for drawing fibres or filaments
    • C03B37/014Manufacture 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]
    • C03B37/018Manufacture 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
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01Manufacture of glass fibres or filaments
    • C03B37/012Manufacture of preforms for drawing fibres or filaments
    • C03B37/014Manufacture 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]
    • C03B37/018Manufacture 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
    • C03B37/01884Means for supporting, rotating and translating tubes or rods being formed, e.g. lathes

Abstract

The invention relates to a holding furnace of an optical fiber preform deposition lathe for plasma chemistry vapor deposition (PCVD) processing. The holding furnace comprises a cubic opened/closed holding furnace body, wherein a longitudinal through slot is formed below the holding furnace body, four corners of an inner cavity in the holding furnace body are provided with large carbon rods, and two ends of the holding furnace body are respectively provided with auxiliary carbon rods; and the holding furnace is characterized in that thermal baffles are respectively arranged on two sides of the inner cavity in the holding furnace body; the inner cavity of the holding furnace body is separated into three cavities along the longitudinal direction; and the inner cavity of the holding furnace body is divided into five temperature areas along the longitudinal direction during heat insulation. The structural arrangement is simple and reasonable, the thermal field distribution curve in the holding furnace can be effectively controlled, and different requirements on the holding temperature along with different axial areas of the quartz liner in the PCVD process are met; according to the thermal baffles, temperature radiation among various areas is blocked, and the requirements of corresponding areas on the different temperature reduction degrees can be met; and moreover, the uniformity and deposition layer precision of the optical fiber preform deposition are enhanced, so that the deposition of the optical fiber preform is improved.

Description

A kind of holding furnace of the prefabricated fiber rod depositing lathe for PCVD processing
Technical field
The present invention relates to a kind of holding furnace of the prefabricated fiber rod depositing lathe for PCVD processing, belong to the preform technical field of processing equipment.
Background technology
Being used for PCVD is the prefabricated fiber rod depositing lathe of PCVD (Plasma Chemical Vapor Deposition) processing, mainly comprises lathe bed structure, mechanical driving part, resonator cavity microwave device and holding furnace device.Holding furnace is in order to the insulation to whole quartz liner, so that quartz liner is finished the deposition of doping quartz layer under the certain temperature condition.But existing holding furnace is rectangular parallelepiped opening and closing furnace bindings, the furnace shell inwall is equipped with thermal insulation layer, the body of heater below offers vertical groove, be used for vertically moving back and forth of microwave device, the whole large carbon-point that is provided in the furnace shell heating adds the auxiliary little carbon-point heating at two ends, above-mentioned holding furnace structure causes in preform PCVD deposition process, temperature curve distributes simple, be difficult to satisfy in the PCVD deposition process along the different demands of the axial different zones of quartz liner for holding temperature, thereby affect homogeneity and the settled layer precision of prefabricated fiber rod depositing.
Summary of the invention
Technical problem to be solved by this invention is the deficiency that exists for above-mentioned prior art and a kind of holding furnace of the prefabricated fiber rod depositing lathe for PCVD processing is provided, it can effectively control thermal field distribution curve in the holding furnace, satisfy in the PCVD deposition process along the different demands of the axial different zones of quartz liner for holding temperature, thereby improve the prefabricated fiber rod depositing quality.
The present invention addresses the above problem the technical scheme that adopts to be: but include rectangular parallelepiped opening and closing thermal insulation furnace body, the thermal insulation furnace body below offers vertical groove, four jiaos of thermal insulation furnace body inner chambers are installed on large carbon-point, auxiliary carbon-point is installed respectively at two ends, it is characterized in that installing respectively thermal baffle in thermal insulation furnace body inner chamber both sides, the thermal insulation furnace body inner chamber longitudinally is divided into three chambeies, during heat insulation work the thermal insulation furnace body inner chamber longitudinally is divided into five temperature provinces.
Press such scheme, described thermal baffle includes solid thermal baffle and hollow heat insulated plate, and described hollow heat insulated plate is spaced by 2 ~ 4 thermal baffles and forms.
Press such scheme, described solid thermal baffle thickness is 50 ~ 200mm, and hollow heat insulated plate thickness is 50 ~ 200mm.
Press such scheme, described thermal baffle plate face equates with thermal insulation furnace body inner chamber cross section, and at the middle mesopore of offering of thermal baffle, vertical groove that straight trough extends to the thermal insulation furnace body below is offered in the mesopore below, with the moving interface phase configuration of resonator cavity microwave device.
Press such scheme, described three chambeies are respectively inlet chamber, main chamber and outlet chamber, install solid thermal baffle between inlet chamber and main chamber, install hollow heat insulated plate between outlet chamber and main chamber.
Press such scheme, described five temperature provinces are respectively inlet chamber humidity province, inlet chamber thermal baffle humidity province, main cavity temperature district, outlet chamber thermal baffle humidity province and outlet chamber humidity province, wherein inlet chamber humidity province temperature remains on 1050 ~ 1140 ℃, main cavity temperature district temperature remains on 1020 ~ 1120 ℃, outlet chamber humidity province temperature remains on 1020 ~ 1110 ℃, the temperature that inlet chamber thermal baffle humidity province temperature is lower than adjacent two humidity provinces is about 10 ~ 50 ℃, and the temperature that outlet chamber thermal baffle humidity province temperature is lower than adjacent two humidity provinces is about 10 ~ 30 ℃.
Press such scheme, the spacer of described both sides thermal baffle and thermal insulation furnace body two ends inwall is respectively 150 ~ 250mm.
Press such scheme, symmetrical dimidiation before and after the described thermal baffle, but adhere to the two halves body of heater of opening and closing thermal insulation furnace body separately.
Press such scheme, but described opening and closing thermal insulation furnace body comprise can before and after the furnace shell of double opening and closing, vertical groove is offered in the furnace shell below, the furnace shell inwall is laid thermal insulation layer.
Press such scheme, four jiaos of thermal insulation furnace body inner chambers are installed on respectively a large carbon-point that passes through the body of heater cavity, the both sides, front and back of inlet chamber install respectively auxiliary in carbon-point, install respectively in the both sides, front and back of outlet chamber and to assist little carbon-point.
Beneficial effect of the present invention is: 1, the body of heater inner-cavity structure arranges advantages of simple, holding furnace inside is divided into five temperature provinces, can effectively control thermal field distribution curve in the holding furnace, satisfy in the PCVD deposition process along the different demands of the axial different zones of quartz liner for holding temperature; 2, thermal baffle has not only stopped the temperature radiation between regional, and passes through the thermal baffle setting of different structure, can solve corresponding zone for the different demand of drop in temperature degree; 3, by the control to thermal field reasonable layout in the holding furnace, strengthened homogeneity and the settled layer precision of prefabricated fiber rod depositing, thereby improved the deposition quality of preform.
Description of drawings
Fig. 1 is the positive sectional structure chart of one embodiment of the invention.
Fig. 2 is the side sectional structure chart of one embodiment of the invention.
Fig. 3 is the interior temperature distribution history of holding furnace and the interior temperature distributing curve diagram of existing holding furnace of the embodiment of the invention.
Embodiment
The invention will be further described below in conjunction with drawings and Examples.But include rectangular parallelepiped opening and closing thermal insulation furnace body, but described opening and closing thermal insulation furnace body comprise can before and after the furnace shell 3 of double opening and closing, vertical groove is offered in the furnace shell below, the furnace shell inwall is laid thermal insulation layer 4.Install respectively thermal baffle in the thermal insulation furnace body inner chamber left and right sides, the thermal insulation furnace body inner chamber longitudinally is divided into three chambeies, described three chambeies are respectively inlet chamber 8, main chamber 9 and outlet chamber 10, between inlet chamber and main chamber, install solid thermal baffle 1, install hollow heat insulated plate 2 between outlet chamber and main chamber, described hollow heat insulated plate is spaced by 3 thermal baffles and forms.Described thermal baffle plate face equates with thermal insulation furnace body inner chamber cross section, and at the middle mesopore of offering of thermal baffle, vertical groove that straight trough extends to the thermal insulation furnace body below, the moving interface phase configuration of mesopore and straight trough and resonator cavity microwave device are offered in the mesopore below; The spacer of described both sides thermal baffle and thermal insulation furnace body two ends inwall is respectively 200mm, symmetrical dimidiation before and after the described thermal baffle, but adhere to the two halves body of heater of opening and closing thermal insulation furnace body separately.The thermal insulation furnace body inner chamber longitudinally is divided into five temperature provinces during heat insulation work, described five temperature provinces are respectively inlet chamber humidity province, inlet chamber thermal baffle humidity province, main cavity temperature district, outlet chamber thermal baffle humidity province and outlet chamber humidity province, wherein inlet chamber humidity province temperature remains on 1100 ℃, main cavity temperature district temperature remains on 1085 ℃, outlet chamber humidity province temperature remains on 1070 ℃, inlet chamber thermal baffle humidity province temperature is 1060 ℃, and outlet chamber thermal baffle humidity province temperature is 1060 ℃.In addition, four jiaos of thermal insulation furnace body inner chambers are installed on respectively a large carbon-point 5 that passes through the body of heater cavity, the both sides, front and back of inlet chamber install respectively auxiliary in carbon-point 6, install respectively auxiliary little carbon-point 7 in the both sides, front and back of outlet chamber, for the heating to holding furnace.
By setting the Heating temperature of big or small carbon-point, make whole holding furnace inside obtain a temperature distribution history, and by use of the present invention, make the interior former temperature distribution history 11 of holding furnace be changed to new temperature distribution history 12 or 13, the differing temps along axial five zones of quartz liner distributes in the preform PCVD process deposits process thereby solved, and heat insulation 1, holding temperature is lower than respectively 30 ~ 40 ℃ of adjacent areas in 100 ~ 200mm width regions of 2 correspondences, 10 ~ 20 ℃ temperature requirements satisfies in the preform PCVD deposition process along the different demands of the axial different zones of quartz liner for holding temperature.

Claims (10)

1. holding furnace that is used for the prefabricated fiber rod depositing lathe of PCVD processing, but include rectangular parallelepiped opening and closing thermal insulation furnace body, the thermal insulation furnace body below offers vertical groove, four jiaos of thermal insulation furnace body inner chambers are installed on large carbon-point, auxiliary carbon-point is installed respectively at two ends, it is characterized in that installing respectively thermal baffle in thermal insulation furnace body inner chamber both sides, the thermal insulation furnace body inner chamber longitudinally is divided into three chambeies, during heat insulation work the thermal insulation furnace body inner chamber longitudinally is divided into five temperature provinces.
2. by the holding furnace of the prefabricated fiber rod depositing lathe for PCVD processing claimed in claim 1, it is characterized in that described thermal baffle includes solid thermal baffle and hollow heat insulated plate, described hollow heat insulated plate is spaced by 2 ~ 4 thermal baffles and forms.
3. by the holding furnace of the prefabricated fiber rod depositing lathe for PCVD processing claimed in claim 2, it is characterized in that described solid thermal baffle thickness is 50 ~ 200mm, hollow heat insulated plate thickness is 50 ~ 200mm.
4. by the holding furnace of claim 1 or 2 described prefabricated fiber rod depositing lathes for PCVD processing, it is characterized in that described thermal baffle plate face equates with thermal insulation furnace body inner chamber cross section, and in the middle of thermal baffle, offer mesopore, vertical groove that straight trough extends to the thermal insulation furnace body below is offered in the mesopore below, with the moving interface phase configuration of resonator cavity microwave device.
5. by the holding furnace of claim 1 or 2 described prefabricated fiber rod depositing lathes for PCVD processing, it is characterized in that described three chambeies are respectively inlet chamber, main chamber and outlet chamber, between inlet chamber and main chamber, install solid thermal baffle, between outlet chamber and main chamber, install hollow heat insulated plate.
6. by the holding furnace of the prefabricated fiber rod depositing lathe for PCVD processing claimed in claim 5, it is characterized in that described five temperature provinces are respectively the inlet chamber humidity province, inlet chamber thermal baffle humidity province, main cavity temperature district, outlet chamber thermal baffle humidity province and outlet chamber humidity province, wherein inlet chamber humidity province temperature remains on 1050 ~ 1140 ℃, main cavity temperature district temperature remains on 1020 ~ 1120 ℃, outlet chamber humidity province temperature remains on 1020 ~ 1110 ℃, the temperature that inlet chamber thermal baffle humidity province temperature is lower than adjacent two humidity provinces is about 10 ~ 50 ℃, and the temperature that outlet chamber thermal baffle humidity province temperature is lower than adjacent two humidity provinces is about 10 ~ 30 ℃.
7. by the holding furnace of claim 1 or 2 described prefabricated fiber rod depositing lathes for PCVD processing, it is characterized in that the spacer of described both sides thermal baffle and thermal insulation furnace body two ends inwall is respectively 150 ~ 250mm.
8. by the holding furnace of claim 1 or 2 described prefabricated fiber rod depositing lathes for PCVD processing, it is characterized in that symmetrical dimidiation before and after the described thermal baffle, but adhere to the two halves body of heater of opening and closing thermal insulation furnace body separately.
9. by the holding furnace of claim 1 or 2 described prefabricated fiber rod depositing lathes for PCVD processing, but it is characterized in that described opening and closing thermal insulation furnace body comprise can before and after the furnace shell of double opening and closing, vertical groove is offered in the furnace shell below, the furnace shell inwall is laid thermal insulation layer.
10. by the holding furnace of the prefabricated fiber rod depositing lathe for PCVD processing claimed in claim 5, it is characterized in that four jiaos of thermal insulation furnace body inner chambers are installed on respectively a large carbon-point that passes through the body of heater cavity, the both sides, front and back of inlet chamber install respectively auxiliary in carbon-point, install respectively in the both sides, front and back of outlet chamber and to assist little carbon-point.
CN201210489281.2A 2012-11-27 2012-11-27 Holding furnace of optical fiber preform deposition lathe for plasma chemistry vapor deposition (PCVD) processing Active CN103043894B (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108298810A (en) * 2018-03-14 2018-07-20 长飞光纤光缆股份有限公司 A kind of PCVD precipitation equipments
CN111470771A (en) * 2020-04-08 2020-07-31 杭州辉吉信息技术有限公司 Optical fiber wire drawing annealing extension tube based on temperature cavity division principle
WO2021208350A1 (en) * 2020-04-13 2021-10-21 烽火通信科技股份有限公司 System and method for improving uniformity of pcvd raw material vapor deposition, and use thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07247133A (en) * 1994-03-09 1995-09-26 Fujikura Ltd Production of optical fiber preform
CN101109075A (en) * 2007-07-24 2008-01-23 长飞光纤光缆有限公司 Plasma resonant cavity waveguide assembly with heat insulating function
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
CN102249532A (en) * 2011-04-15 2011-11-23 长飞光纤光缆有限公司 Optical fiber preform deposition lathe for PCVD (plasma chemical vapor deposition) processing
CN202329128U (en) * 2011-11-16 2012-07-11 宜兴市前锦炉业设备有限公司 Multi-temperature-area tubular furnace

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07247133A (en) * 1994-03-09 1995-09-26 Fujikura Ltd Production of optical fiber preform
CN101109075A (en) * 2007-07-24 2008-01-23 长飞光纤光缆有限公司 Plasma resonant cavity waveguide assembly with heat insulating function
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
CN102249532A (en) * 2011-04-15 2011-11-23 长飞光纤光缆有限公司 Optical fiber preform deposition lathe for PCVD (plasma chemical vapor deposition) processing
CN202329128U (en) * 2011-11-16 2012-07-11 宜兴市前锦炉业设备有限公司 Multi-temperature-area tubular furnace

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108298810A (en) * 2018-03-14 2018-07-20 长飞光纤光缆股份有限公司 A kind of PCVD precipitation equipments
CN111470771A (en) * 2020-04-08 2020-07-31 杭州辉吉信息技术有限公司 Optical fiber wire drawing annealing extension tube based on temperature cavity division principle
WO2021208350A1 (en) * 2020-04-13 2021-10-21 烽火通信科技股份有限公司 System and method for improving uniformity of pcvd raw material vapor deposition, and use thereof

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Free format text: CORRECT: APPLICANT; FROM: CHANGFEI FIBRE-OPTICAL + OPTICAL CABLE CO., LTD. TO: YANGTZE OPTICAL FIBRE AND CABLE CO., LTD

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Address after: 430073 Hubei city of Wuhan province Wuchang two Guanshan Road No. four

Applicant after: Yangtze Optical Fibre and Cable Co., Ltd

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