CN203319858U

CN203319858U - Optical fiber drawing furnace

Info

Publication number: CN203319858U
Application number: CN201320398260XU
Authority: CN
Inventors: 俞华; 黄本华; 周震华; 陈强; 洪留明
Original assignee: FA'ERSHENG PHOTON Co Ltd JIANGSU
Current assignee: FA'ERSHENG PHOTON Co Ltd JIANGSU
Priority date: 2013-07-05
Filing date: 2013-07-05
Publication date: 2013-12-04
Anticipated expiration: 2023-07-05

Abstract

The utility model relates to an optical fiber drawing furnace. The optical fiber drawing furnace comprises a furnace body, a heating body, a heat-preservation body, a middle sleeve, a flow guiding pipe, an extending pipe and a furnace roof gas disc, and is characterized by further comprising a separation ring, an elastic graphite annulus piece and a gas guiding disc, wherein the gas guiding disc is installed on the furnace roof gas disc, the elastic graphite annulus piece is installed on a hollow annular disc, the separation ring is arranged between the flow guiding pipe and the extending pipe, and a plurality of first air inlets are formed in the lateral wall of the extending pipe at the upper end of the separation ring. The optical fiber drawing furnace has the advantages of being suitable for drawing preform with a large diameter, and optical fiber preform with large diameter fluctuation, enabling graphite dust not to be attached to the preform easily and effectively controlling the air flow state inside the drawing furnace.

Description

A kind of fibre drawing furnace

Technical field

The utility model relates to a kind of equipment for fiber manufacturing, relates in particular to a kind of fibre drawing furnace that is applicable to draw prefabricated rods that diameter is larger and the larger preform of diameter fluctuation.

Background technology

Current fibre drawing furnace comprises body of heater, heating element, thermal insulator, middle sleeve, thrust-augmenting nozzle, extension tube and top gas dish, the upper and lower wall correspondence of body of heater respectively has wire drawing hole and lower wire drawing hole on one, middle sleeve is arranged in body of heater through upper wire drawing hole and lower wire drawing hole, thermal insulator is arranged in body of heater, heating element is arranged between middle sleeve and thermal insulator in body of heater, on upper wire drawing hole, the top gas dish is set, extension tube one end is communicated with on the body of heater outside lower wire drawing hole, and thrust-augmenting nozzle one end is sleeved in middle sleeve, and the thrust-augmenting nozzle the other end is sleeved in extension tube, the outer side wall of top gas dish is provided with transfer port, evenly has several gas orifices facing to the top gas dish center of circle on inner side-wall, when drawing optical fiber, the quartz glass bar end of preform (hereinafter to be referred as prefabricated rods) is constantly moved down and enters inside heating furnace, because the fiber drawing furnace internal temperature reaches 2200 degrees centigrade, so high purity graphite is commonly used to the material as the heating element of fiber drawing furnace, between prefabricated rods in upper wire drawing hole and insertion stove, little gap is arranged, in order to prevent making at high temperature oxidation of graphite after extraneous air from entering fiber drawing furnace, affect the work-ing life of heating element, graphite dust after simultaneous oxidation can stick to prefabricated rods and melt part, cause the decline of the fiber strength made, need in fiber drawing furnace, pass into rare gas element, as argon gas, helium etc., its gas orifice by the top gas dish is blown in stove, the inert gas atmosphere that keeps certain malleation in stove, on the other hand, drawing optical fibers requires the air-flow of fiber drawing furnace to keep stable laminar flow regime, in drawing process, the variation of air-flow can cause that the diameter of optical fiber changes and fiber strength descends, it is less that this requires the prefabricated rods diameter to change, and generally, by special-purpose extension device, the prefabricated rods that diameter is changed is greatly at high temperature extended evenly, yet along with the preform diameter is increasing, it is large that the fluctuation range of preform diameter just becomes, the gap fluctuation range that makes the wire drawing hole and insert between the prefabricated rods in stove just becomes large, just is difficult to thus control the laminar flow stability of the high-temperature gas in fiber drawing furnace.

For this reason, U.S. Pat 2006/280578A1 discloses and a kind ofly can respond prefabricated rods external diameter change for sealing the method in prefabricated rods and wire drawing fire door gap.The method has been used and has been comprised that outer shroud and interior loops close the wear ring formed, and by spring, the sealing ring is shifted onto to the surface of prefabricated rods; .TOHKEMY 2007-70189 communique discloses a kind of containment member, and the sealing member has the structure of brush and sac like at the wire drawing fire door.Also has the design that directly by graphite soft felt, seals prefabricated rods and wire drawing fire door; Patent of invention 200810134932.x discloses a kind of structure of graphite flake sealing of two sealing units, this structure is sealed by the elasticity of the graphite flake of particular design, yet, in these designs, because fiber drawing furnace adopts downward air-flow trend, the sealing material that fire door is used, under the effect of high temperature and friction, causes some graphite soft felt carbon dusts to enter fiber drawing furnace, thereby can cause the strength degradation of optical fiber; In patent of invention 200810134932.x, in the structure of two unit graphite flake sealings, the elasticity of graphite flake is at high temperature very little, and the prefabricated rods changed for larger diameter can cause gas leakage, causes the oxidation of fiber drawing furnace.

Summary of the invention

For above shortcoming, the purpose of this utility model is to provide a kind of fibre drawing furnace, it can be applicable to draw prefabricated rods and the larger preform of diameter fluctuation that diameter is larger, can make graphite dust be difficult for sticking on prefabricated rods simultaneously and can effectively control the air-flow condition in fiber drawing furnace.

Technology contents of the present utility model is that a kind of fibre drawing furnace comprises body of heater, heating element, thermal insulator, middle sleeve, thrust-augmenting nozzle, extension tube and top gas dish; It is characterized in that it also comprises spacer ring, elastic graphite ring plate and air-guide disk; Air-guide disk comprises a cavity ring dish and some ring plates, in the cavity ring dish, the ring place is an open ports, upper inwall, lower inwall upper and lower adjacent be staggered installation of of some ring plates in the cavity ring dish, the upper inwall at the close outer side wall of cavity ring dish place is provided with the some production wells of a circle; Air-guide disk is arranged on the top gas dish and makes production well vertically upward, and the elastic graphite ring plate is arranged on the cavity ring dish of production well inboard; Spacer ring is arranged between thrust-augmenting nozzle and extension tube, make the thrust-augmenting nozzle outer wall respectively and extension tube inwall and middle sleeve inwall between be formed with gap; Be provided with some the first air inlet ports on the extension tube sidewall of spacer ring upper end.

For further protecting the elastic graphite ring plate, the utility model also comprises the sealing gland cover; The sealing gland enclosure is contained on the cavity ring dish of production well inboard and covers the elastic graphite ring plate, is provided with some the second air inlet ports on the sealing gland cover; Be provided with sealing gland cover endoporus at sealing gland cover center.

The advantage that the utility model compared with prior art had is: the elastic graphite ring plate can make fiber drawing furnace can be applicable to draw prefabricated rods and the larger preform of diameter fluctuation that diameter is larger; Extension tube place by furnace bottom is to input protection gas in body of heater and upwards flow and flow out from the production well of air-guide disk, and the shielding gas of the gentle sealing cover input of air-guide disk also flows out from the production well of air-guide disk, plays thus the effect of current stabilization; Air-guide disk plays the collecting action of ash content simultaneously; The utility model can be applicable to draw prefabricated rods and the larger preform of diameter fluctuation that diameter is larger thus, can make graphite dust be difficult for sticking on prefabricated rods simultaneously and can effectively control the air-flow condition in fiber drawing furnace.

The accompanying drawing explanation

Fig. 1 is structural representation of the present utility model.

The structural representation that Fig. 2 is air-guide disk in the utility model.

Fig. 3 be in Fig. 2 A-A to schematic diagram.

Embodiment

As shown in Figure 1, Figure 2 and Figure 3, a kind of fibre drawing furnace comprises body of heater 1, heating element 2, thermal insulator 3, middle sleeve 4, thrust-augmenting nozzle 5, extension tube 6 and top gas dish 7; It is characterized in that it also comprises spacer ring 8, elastic graphite ring plate 9, the gentle sealing cover 11 of air-guide disk 10; Air-guide disk 10 comprises a cavity ring dish 10.1 and some ring plates 10.2, the interior ring of cavity ring dish 10.1 place is an open ports 10.3, upper inwall 10.4, lower inwall 10.5 upper and lower adjacent be staggered installation of of some ring plates 10.2 in the cavity ring dish, the upper inwall 10.4 at cavity ring dish 10.1 close outer side wall 10.6 places is provided with the some production wells 10.7 of a circle; Air-guide disk 10 is arranged on top gas dish 7 and makes production well 10.7 vertically upward, and elastic graphite ring plate 9 is arranged on the cavity ring dish 10.1 of production well 10.7 inboards; Spacer ring 8 is arranged between thrust-augmenting nozzle 5 and extension tube 6, make thrust-augmenting nozzle 5 outer walls respectively and extension tube 6 inwalls and middle sleeve 4 inwalls between be formed with gap 12; Be provided with some the first air inlet ports 6.1 on extension tube 6 sidewalls of spacer ring 8 upper ends; Sealing gland cover 11 is sleeved on the cavity ring dish 10.1 of production well 10.7 inboards and covers elastic graphite ring plate 9, is provided with some the second air inlet ports 11.1 on sealing gland cover 11; Be provided with sealing gland cover endoporus 11.2 at sealing gland cover 11 centers.

Principle of work of the present utility model is, preform 13 ends are constantly moved down and enter in heating furnace body 1, by 13 heating of 2 pairs of preforms of heating element, pass into inert protective gas by the first air inlet port 6.1 simultaneously, this inert protective gas upwards flows in body of heater by gap 12, wherein the part inert protective gas by thrust-augmenting nozzle 5 by the optical fiber 14 that flows downward to protect drawing in extension tube 6; All the other inert protective gas in body of heater on flow, by production well 10.7, flowed out after then entering air-guide disk 10, ring plate 10.2 is blocked the volatile matter particle in inert protective gas and it is deposited in cavity ring dish 10.1 simultaneously; Inputted inert protective gas with protection elastic graphite ring plate 9 and prevented that between elastic graphite ring plate 9 and preform 13, nothing has airflow to enter by the second air inlet port 11.1 simultaneously with this, the inert protective gas of the second air inlet port 11.1 inputs flows out from production well 10.7 after flowing into air-guide disk 10 downwards; The gas orifice 7.1 of top gas dish 7 is blown into inert protective gas in stove, so that body of heater 1 upper end preform 13 ingresss enter in body of heater without air, the inert protective gas of gas orifice 7.1 inputs flows out from production well 10.7 after upwards flowing into air-guide disk 10.

Claims

1. a fibre drawing furnace comprises body of heater, heating element, thermal insulator, middle sleeve, thrust-augmenting nozzle, extension tube and top gas dish; It is characterized in that it also comprises spacer ring, elastic graphite ring plate and air-guide disk; Air-guide disk comprises a cavity ring dish and some ring plates, in the cavity ring dish, the ring place is an open ports, upper inwall, lower inwall upper and lower adjacent be staggered installation of of some ring plates in the cavity ring dish, the upper inwall at the close outer side wall of cavity ring dish place is provided with the some production wells of a circle; Air-guide disk is arranged on the top gas dish and makes production well vertically upward, and the elastic graphite ring plate is arranged on the cavity ring dish of production well inboard; Spacer ring is arranged between thrust-augmenting nozzle and extension tube, make the thrust-augmenting nozzle outer wall respectively and extension tube inwall and middle sleeve inwall between be formed with gap; Be provided with some the first air inlet ports on the extension tube sidewall of spacer ring upper end.