WO2018209720A1

WO2018209720A1 - Optical fiber annealing extension tube

Info

Publication number: WO2018209720A1
Application number: PCT/CN2017/085703
Authority: WO
Inventors: 郝昌平; 宋海瑞; 陈伟; 罗干; 董魏; 曹少波; 贺作为; 张良; 袁健
Original assignee: 江苏亨通光纤科技有限公司; 江苏亨通光电股份有限公司
Priority date: 2017-05-15
Filing date: 2017-05-24
Publication date: 2018-11-22
Also published as: CN107082560B; DE112017000445T5; CN107082560A

Abstract

An optical fiber (1) annealing extension tube, comprising a quartz main tube (2). The middle position in the axial direction of the quartz main tube (2) is a variable-diameter tube section (4); the tube diameters of the tube body located at two sides of the variable-diameter tube section (4) of the quartz main tube (2) are less than the minimum tube diameter in the variable-diameter tube section (4); a quartz branch tube (6) is connected to the variable-diameter tube section (4); the quartz branch tube (6) is connected at the position having a maximum tube diameter of the variable-diameter tube section (4); the quartz branch tube (6) communicates with the inside of the quartz main tube (2); the other end of the quartz branch tube (6) is connected with a negative pressure suction device; the tube diameter of a middle tube section in the axial direction of the variable-diameter tube section (4) is maximum; the tube diameters of the tube body located at two sides of the middle tube section of the variable-diameter tube section (4) are gradually reduced. The quartz main tube (2) optimizing the structure design can perform, in coordination with the negative pressure suction device, online cleaning treatment on oxides, volatile substances, etc. generated in an optical fiber (1) furnace and entering the annealing extension tube, so that, on the premise of ensuring the quality of the optical fiber (1), the fracture rate of the optical fiber (1) is reduced, and production efficiency is improved.

Description

Fiber annealing extension tube

Technical field

The invention belongs to the technical field of quartz optical fibers, and in particular relates to an optical fiber annealing extension tube.

Background technique

With the recovery of the optical fiber market, the demand for optical fiber is increasing, and major fiber manufacturers are speeding up to improve production efficiency to meet market demand. The fiber annealing extension tube is arranged under the drawing furnace to prevent the quenching of the fiber after the fiber is extracted and affects its performance. The conventional fiber annealing adopts a combination of a graphite liner and a metal tube, for example, the fiber disclosed in Chinese patents CN201121163Y and CN102079623B. The annealing device has simple operation and strong practicability, and has a certain effect on the fiber retreat. However, due to the limitation of the metal material itself, under the influence of high and low temperature circulation for a long time, the metal deformation is serious, thereby affecting the quality of the optical fiber.

On the other hand, as the size of the preform increases, the time for drawing a single rod gradually increases (the longest drawing time can be about 6 days), resulting in an increase in oxides generated in the fiber furnace. At the end of the light bar, the accumulated oxides and volatiles gradually accumulate into the annealing extension tube. The narrow space inside the annealing extension tube is easily blocked by oxides and volatiles, which affects the gas flow, causing the bare fiber to fluctuate and the volatile matter is extremely easy. Dropped again and adhered to the surface of bare fiber. Even at high temperature, SiC particles will enter the inside of bare fiber, causing micro cracks on the surface of the fiber. Under high temperature and high speed traction, the surface defects of the fiber will increase, and the strength of the fiber will be reduced. Performance, screening tests, and cabling characteristics have an adverse effect.

Summary of the invention

In order to solve the above technical problems, the present invention provides an optical fiber annealing extension tube, an optimized structural design of the quartz main tube, and a negative pressure suction device capable of performing on-line oxides and volatiles generated in the optical fiber furnace and entering the annealing extension tube. Under the premise of cleaning and ensuring the quality of the optical fiber, the fiber breakage rate of the optical fiber is reduced, and the production efficiency is improved.

In order to achieve the above object, the technical solution of the present invention is as follows: a fiber annealing extension tube, including stone The British main pipe is characterized in that: the intermediate portion in the axial direction of the quartz main pipe is a reduced diameter pipe segment, and the pipe diameter of the quartz main pipe located on both sides of the variable diameter pipe segment is smaller than the minimum pipe diameter in the variable diameter pipe segment, the change a quartz branch pipe is connected to the diameter pipe section, and the quartz branch pipe is connected at a maximum pipe diameter of the variable diameter pipe section, and the quartz branch pipe is connected to the interior of the quartz main pipe;

The other end of the quartz branch pipe is connected with a vacuum suction device;

The diameter of the intermediate pipe section in the axial direction of the reducer pipe section is the largest, and the diameter of the pipe body of the reducer pipe section located on both sides of the intermediate pipe section is gradually reduced.

In a preferred embodiment of the present invention, the quartz main pipe has two parts which are separately arranged and coaxially connected, and are respectively a quartz tube 1 and a quartz tube 2, and the quartz tube is axially The diameter of the lower end portion is gradually increased, the diameter of the upper end portion of the quartz tube is gradually reduced, and the end of the lower end of the quartz tube is connected to the end of the upper end of the quartz tube 2, and the quartz branch is connected to the quartz. On the upper end of the tube 2.

In a preferred embodiment of the present invention, it is further included that both ends of the quartz main pipe are connected with a gas pipe through which an inert shielding gas is introduced into the quartz main pipe.

In a preferred embodiment of the present invention, the quartz branch is further connected to both sides of the quartz main tube, and the other ends of the quartz branch tubes are connected to the vacuum suction device.

In a preferred embodiment of the present invention, the vacuum suction device further includes a suction pump and a suction pipe. One end of the suction pipe is connected to the quartz branch pipe, and the other end thereof is connected to the suction pump. Pressure regulators and pressure gauges are also provided on the suction pipe.

In a preferred embodiment of the present invention, the tube wall of the upper end portion of the quartz tube is further provided with a card slot, and an axially lower end portion of the quartz tube is inserted into the card slot and sealedly connected.

In a preferred embodiment of the present invention, the length of the reduced diameter pipe section is 0.025 to 0.03 times the length of the quartz main pipe.

In a preferred embodiment of the present invention, the method further includes: the reduced diameter pipe section is a variable diameter pipe section that changes stepwise, and the diameter of the pipe body on the adjacent step is changed by 10 mm to 15 mm.

In a preferred embodiment of the invention, the method further includes providing a flow meter on the gas pipe.

In a preferred embodiment of the invention, further comprising two of the suction tube and the quartz branch tube The contact jacket has a high temperature resistant leather tube.

The beneficial effects of the invention are:

Firstly, the quartz main pipe with optimized structural design and the negative pressure suction device can clean the oxides and volatiles generated in the fiber-optic furnace and enter the annealing extension tube, and ensure the fiber quality under the premise of ensuring the quality of the optical fiber. Fiber rate, improve production efficiency;

Secondly, according to the theory of gas flow and pressure gradual change, and fully considering the influence of structural changes on the flow of gas, the structure of the quartz main pipe is designed. During the high-speed drawing process, the gas in the quartz main pipe is driven by the high-speed moving fiber to enter the variable-diameter pipe section. The gas movement in the area of the reduced diameter section tends to be laminar; at the same time, when the oxide and volatile matter in the furnace are driven by the optical fiber, the airflow becomes slow and the quartz enters into the area of the variable diameter pipe section. The oxides and volatiles in the main pipe are piled up in the area of the reducing pipe section, and the waste vacuuming device is designed to clean the waste accumulated in the area of the reducing pipe section, and the maximum removal rate of the waste is removed;

Third, the quartz main pipe with the variable diameter pipe section is designed as two parts that can be disassembled, which is convenient for cleaning the inside of the quartz main pipe after the drawing is completed;

Fourth, during the process of pumping waste by the vacuum suction device, part of the gas in the quartz main pipe is also sucked out, and an inert gas is introduced into the quartz main pipe through the gas pipe, and the inert gas that is introduced on the one hand protects, and the other On the one hand, the inert gas that is introduced enters the balance of the gas pressure in the tube when the gas in the tube is sucked away, ensuring the normal production of the optical fiber, and is advantageous for improving the drawing quality of the optical fiber.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the technical description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some implementations of the present invention. For example, other drawings may be obtained from those of ordinary skill in the art in light of the inventive work.

Figure 1 is a schematic view showing the structure of a preferred embodiment of the present invention;

2 is a schematic structural view of a quartz tube 2 according to a preferred embodiment of the present invention;

Figure 3 is a schematic view showing the structure of a joint between a quartz tube 1 and a quartz tube 2 in a preferred embodiment of the present invention.

Among them: 1-fiber, 2-quartz main pipe, 4-reducing pipe section, 6-quartz branch pipe, 8-quartz pipe one, 10-quartz tube 2, 12-air tube, 14-suction pump, 16-suction tube, 18-pressure regulating valve, 20-pressure gauge, 22-flow meter, 24-heat resistant leather tube, 26-card slot, 28-rubber ring.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Example

As shown in FIG. 1 , in this embodiment, an optical fiber annealing extension tube is disclosed, which comprises a quartz main tube 2, and a quartz main tube 2 is connected to the drawing furnace. When in use, the optical fiber 1 passes through a central shaft hole in the quartz main tube 2, and the above change A quartz branch pipe 6 is connected to the diameter pipe section 4, and the quartz branch pipe 6 is connected to the largest pipe diameter of the reduced diameter pipe section 4, the quartz branch pipe 4 is in communication with the interior of the quartz main pipe 2, and the other end of the quartz branch pipe 6 is connected with a vacuum suction. In the technical solution of the present invention, the intermediate portion of the quartz main pipe 2 in the axial direction is the reduced diameter pipe section 4, and the pipe diameter of the quartz main pipe 2 located on both sides of the variable diameter pipe section 4 is smaller than the minimum pipe diameter of the variable diameter pipe section 4. The pipe diameter of the intermediate pipe section in the axial direction of the above-mentioned variable diameter pipe section 4 is the largest, and the diameter of the pipe body of the above-mentioned variable diameter pipe section 4 on both sides of the intermediate pipe section is gradually reduced. Specifically, in the technical solution of the embodiment, the above-mentioned variable diameter pipe section The length of 4 is 0.025 to 0.03 times the length of the quartz main pipe 2. For example, the length of the quartz main pipe 2 is 1.2 m (1200 mm), the length of the variable diameter pipe section 4 is 30 to 36 mm, and the variable diameter pipe section 4 is disposed in the quartz main pipe 2 axial direction. Intermediate part; further In the technical solution of the embodiment, the reduced diameter pipe section 4 is preferably a variable diameter pipe section 4 that changes stepwise, and the diameter of the pipe body on the adjacent step is changed by 10 mm to 15 mm. For example, the quartz main pipe 2 is located on both sides of the variable diameter pipe section 4. The diameter of the pipe body is designed to be 50 mm, and the diameter of the pipe body of the variable diameter pipe section 4 is 60 mm, 70 mm, 80 mm, 80 mm, 70 mm, 60 mm, and the length of each stepped pipe body is 4 mm to 5 mm.

The quartz main pipe 2 of the above structural design fully considers the influence of structural changes on the flow of the air flow. During the high-speed drawing process, the gas in the quartz main pipe 2 is driven by the high-speed moving optical fiber 1 into the variable-diameter pipe section 4, and the gas in the variable-diameter pipe section 4 region The movement slows down to laminar motion; at the same time, when the oxides and volatiles in the drawing furnace are driven by the optical fiber 1 into the region of the variable diameter pipe section 4, due to the increase in space, The airflow is slowed down, and the oxides and volatiles entering the quartz main pipe 2 are accumulated in the area of the variable diameter pipe section 4, and the waste accumulated in the area of the variable diameter pipe section 4 is cleaned online by the negative pressure suction device designed to achieve the maximum clearance rate. Under the premise of ensuring the quality of the optical fiber, the fiber is cut off on the line to reduce the fiber breakage rate and improve the production efficiency.

In the technical solution of the embodiment, the structure of the vacuum suction device for sucking waste is as follows:

The vacuum suction device includes a suction pump 14 and a suction pipe 16. One end of the suction pipe 16 is connected to the quartz branch pipe 6, and the other end thereof is connected to the suction pump 14, and the suction pipe 16 is further provided with a pressure regulating valve. 18 and the pressure gauge 20; the suction pump 14 is activated to generate a negative pressure, and the waste accumulated at the reduced diameter pipe section 4 is sucked out from the quartz branch pipe 6 under the negative pressure, and is evacuated through the suction pipe 16 into the waste recovery device. The effect of the quartz main pipe 2 is cleaned online, and the magnitude of the negative pressure is adjusted by the pressure regulating valve 18, while the current suction pressure value is visually displayed on the pressure gauge 20.

The two contact holes of the suction pipe 16 and the quartz branch pipe 6 are provided with a high temperature resistant leather pipe 24, and the suction pipe 16 is a metal pipe during use, and the quartz branch pipe 6 is a quartz pipe, and the high temperature resistant leather pipe 24 is designed. The sealing action to the pipe connection, on the other hand, acts as a soft connection to protect the quartz branch pipe 6 from damage.

In order to balance the suction force in the quartz main tube 2 without affecting the normal fiber penetration of the optical fiber 1, in the technical solution of the embodiment, the quartz tube 6 is connected to both sides of the axially symmetric side of the quartz main tube 2, and the negative pressure of the above structure The suction device has two of the two quartz branch pipes 6, respectively.

During the process of pumping waste by the vacuum suction device, part of the gas in the quartz main pipe 2 is also sucked out. In order not to affect the normal fiber penetration in the quartz main pipe 2, the two ends of the quartz main pipe 2 are connected in the axial direction. The gas pipe 12 is provided with a flow meter 22 on the gas pipe 12, and an inert shielding gas is introduced into the quartz main pipe 2 through the gas pipe 12, and the current gas inlet amount can be subjectively viewed through the flow meter 22; The inert gas is introduced, on the one hand, the inert gas is protected, and on the other hand, the inert gas is used to balance the pressure in the tube when the gas in the quartz main tube 2 is sucked away, ensuring the normal production of the fiber. It is carried out to improve the quality of the fiber drawing.

As a further improvement of the present invention, the quartz main pipe 2 has two parts which are separately arranged and coaxially connected, and are respectively a quartz tube 8 and a quartz tube 2, and the quartz tube 8 is axially The diameter of the lower end portion is gradually increased, and the diameter of the upper end portion of the quartz tube 2 in the axial direction is gradually reduced, and the end of the lower end portion of the quartz tube 8 is connected to the end of the upper end portion of the quartz tube 2, and the quartz branch tube 6 is connected The upper end of the quartz tube 2 is 10 . The quartz tube 8 and the quartz tube 10 are fixed in a detachable manner; specifically, as shown in FIG. 2 and FIG. 3, the tube wall of the upper end of the quartz tube 2 is provided with a card slot 26, the quartz The lower end portion of the tube 8 in the axial direction is inserted into the card slot 26 and then sealedly connected. The inserted connector is sealed and fixed by a high temperature resistant rubber ring 28. The width of the rubber ring 28 is 2-5 cm, and the diameter of the quartz tube is 8 and The largest diameter of both

quartz tubes

2 and 10. On the one hand, the high temperature resistant rubber ring 28 is fastened to the quartz tube 8 and the quartz tube 2, so that the two are connected together, and on the other hand, the sealing effect after the connection. The quartz main pipe 2 with the variable diameter pipe section 4 is designed as two parts that can be disassembled, and is convenient for cleaning the inside of the quartz main pipe 2 after the drawing is completed. For example, after the drawing is completed, the quartz tube 8 and the quartz tube 2 are disassembled, and the time is changed. The diameter pipe sections are respectively located at the ends of the quartz tube 8 and the quartz tube 2, which can be used to thoroughly clean the inside of the variable diameter pipe section.

The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments are obvious to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but the scope of the invention is to be accorded

Claims

A fiber annealing extension pipe, comprising a quartz main pipe, wherein: an intermediate portion of the quartz main pipe in the axial direction is a reduced diameter pipe segment, and a pipe diameter of the quartz main pipe located on both sides of the variable diameter pipe segment is smaller than a variable diameter pipe segment a minimum pipe diameter, a quartz branch pipe is connected to the variable diameter pipe section, and the quartz branch pipe is connected at a maximum pipe diameter of the variable pipe section, and the quartz branch pipe is connected to the interior of the quartz main pipe;

The other end of the quartz branch pipe is connected with a vacuum suction device;

The diameter of the intermediate pipe section in the axial direction of the reducer pipe section is the largest, and the diameter of the pipe body of the reducer pipe section located on both sides of the intermediate pipe section is gradually reduced.
The optical fiber annealing extension tube according to claim 1, wherein the quartz main tube has two parts which are separately arranged and coaxially connected, and are respectively a quartz tube one and a quartz tube two, the quartz The diameter of the lower end of the tube is gradually increased, the diameter of the upper end of the quartz tube is gradually reduced, and the end of the lower end of the quartz tube is connected to the end of the upper end of the quartz tube 2 The quartz branch pipe is connected to the upper end portion of the quartz tube 2.
The optical fiber annealing extension tube according to claim 1 or 2, wherein a gas pipe is connected to both ends of the quartz main pipe axial direction, and an inert shielding gas is introduced into the quartz main pipe through the gas pipe.
The optical fiber annealing extension tube according to claim 1, wherein both sides of the quartz main tube are axially symmetrically connected to the quartz branch tube, and the other ends of the quartz branch tubes are connected to a vacuum suction. Device.
The optical fiber annealing extension tube according to claim 1 or 4, wherein the negative pressure suction device comprises a suction pump and a suction pipe, one end of the suction pipe is connected to the quartz branch pipe, and the other end thereof is A suction pump is connected, and the suction pipe is further provided with a pressure regulating valve and a pressure gauge.
The optical fiber annealing extension tube according to claim 2, wherein a wall of the upper end of the quartz tube is provided with a card slot, and an axially lower end portion of the quartz tube is inserted into the card slot. Inner and rear sealed connections.
A fiber annealing extension tube according to claim 1 or 2, wherein: said change The length of the diameter pipe section is 0.025 to 0.03 times the length of the quartz main pipe.
The optical fiber annealing extension tube according to claim 7, wherein the reduced diameter pipe section is a variable diameter pipe section that changes stepwise, and the diameter of the pipe body on the adjacent step is changed by 10 mm to 15 mm.
A fiber annealing extension tube according to claim 3, wherein the gas pipe is provided with a flow meter.
A fiber annealing extension tube according to claim 5, wherein the two contact jackets of the suction tube and the quartz branch tube are jacketed with a high temperature resistant skin tube.