Inert gas recovery method for optical fiber manufacturing

Abstract

The invention relates to the technical field of optical fiber manufacturing, in particular to an inert gas recovery method for optical fiber manufacturing, which is applied to an optical fiber manufacturing workshop with a plurality of production lines, induction furnaces and strip line electromagnetic valves are arranged on the production lines, and comprises the following steps: S1, collecting gas output by annealing pipes at the bottoms of the induction furnaces to obtain first gas; s2, filtering the first gas to obtain second gas; s3, under the condition that the first set threshold value is met, the strip line electromagnetic valve is opened, the second gas continues to be conveyed, otherwise, the strip line electromagnetic valve is closed, and the second gas is blocked in the corresponding production line; s4, uniformly extracting the continuously transmitted second gas to obtain third gas; and S5, under the condition that a second set threshold value is met, the third gas is recycled to the storage tank, and otherwise, the third gas is exhausted. According to the method, the structure of the induction furnace does not need to be changed, better variability and universality are achieved, and the recovery purity and the recovery efficiency are improved.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber manufacturing, and in particular to an inert gas recovery method used in optical fiber manufacturing. Background Art

[0002] In optical fiber manufacturing, drawn optical rods (commonly known as optical fiber preforms) are converted into optical fibers with specific optical properties by high-temperature melting. This process is usually carried out in an induction furnace, which uses a strong magnetic field generated by an induction coil to rapidly heat the graphite parts in the furnace to a temperature of more than 2000 degrees Celsius to melt the drawn optical rods.

[0003] High temperature conditions can easily lead to a violent oxidation reaction between graphite parts and oxygen in the air, accelerating the wear and damage of graphite parts. In order to protect graphite parts and meet the continuity of optical fiber production, the induction furnace must be filled with inert gas to isolate oxygen and prevent oxidation reactions. Inert gas will not react chemically with the materials in the furnace, and will not be consumed while protecting graphite parts.

[0004] The cost of using inert gas accounts for a large proportion of the total cost of optical fiber manufacturing. Recycling inert gas is an optimization direction in optical fiber manufacturing. However, in actual operation, since the structure of the induction furnace needs to take into account the feeding of the drawing light rod and the output of the optical fiber, its upper and lower parts cannot be completely sealed, which hinders the recovery of inert gas. Existing inert gas recovery is often achieved by changing the structure of the induction furnace, which is costly, poor in variability and versatility; lack of control over the inert gas recovery threshold reduces the recovery purity and efficiency of the inert gas. These problems are particularly obvious when there are a large number of induction furnaces. Summary of the invention

[0005] To this end, the technical problem to be solved by the present invention is to overcome the problem that the recovery of inert gas in the prior art requires changing the structure of the induction furnace, resulting in high cost, poor variability and versatility, and lack of control over the inert gas recovery threshold. An inert gas recovery method for optical fiber manufacturing is provided, which does not require changing the structure of the induction furnace, has low cost, and has good variability and versatility; the recovery threshold of the inert gas is controlled to improve the recovery purity and recovery efficiency.

[0006] In order to solve the above technical problems, the present invention provides an inert gas recovery method for optical fiber manufacturing, which is applied to an optical fiber manufacturing workshop with multiple production lines, each of which is equipped with an induction furnace and a line solenoid valve, comprising:

[0007] Step S1: collecting the gas output from the bottom annealing tube of the induction furnace to obtain a first gas;

[0008] Step S2: filtering the first gas to obtain a second gas;

[0009] Step S3: controlling the line solenoid valves configured on each of the production lines according to a first set threshold value, and when the first set threshold value is met, the line solenoid valves are opened, and the second gas continues to be transmitted; when the first set threshold value is not met, the line solenoid valves are closed, and the second gas is blocked in the corresponding production line;

[0010] Step S4: uniformly extracting the second gas that continues to be transmitted to obtain a third gas;

[0011] Step S5: When the third gas meets the second set threshold, the third gas is recovered to the storage tank; when the third gas does not meet the second set threshold, the third gas is discharged.

[0012] In one embodiment of the present invention, after filtering the first gas to obtain the second gas, the first set threshold is set according to the rated power of the corresponding induction furnace on the production line, or the first set threshold is set according to the remaining length of the wire drawing polished rods on the production line waiting to be put into the corresponding induction furnace.

[0013] In one embodiment of the present invention, when the operating power of the corresponding induction furnace on the production line is less than 20% of the rated power, or the remaining length of the drawn polished rods on the production line waiting to be put into the corresponding induction furnace is less than 200 kilometers, the corresponding line solenoid valves on the production line are closed; when the operating power of the corresponding induction furnace on the production line is not less than 20% of the rated power, or the remaining length of the drawn polished rods on the production line waiting to be put into the corresponding induction furnace is not less than 200 kilometers, the corresponding line solenoid valves on the production line are opened.

[0014] In one embodiment of the present invention, the second set threshold is set according to the oxygen content of the third gas.

[0015] In one embodiment of the present invention, when the oxygen content of the third gas does not exceed 0.4%, the third gas is recovered to a storage tank; when the oxygen content of the third gas exceeds 0.4%, the third gas is discharged.

[0016] In one embodiment of the present invention, after the second gas that is continuously transmitted is uniformly extracted to obtain the third gas, the third gas is prevented from flowing back in a recovery direction or an external discharge direction based on a first one-way valve.

[0017] In one embodiment of the present invention, when the third gas meets the second set threshold, before the third gas is recovered to the storage tank, the second one-way valve is used to prevent the third gas from flowing back in the recovery direction.

[0018] In one embodiment of the present invention, step S6 is further included: the third gas recovered to the storage tank is transmitted and utilized to obtain a fourth gas; wherein the flow rate of the fourth gas is detected, and the flow rate of the fourth gas transmitted from the storage tank to the user end is controlled based on the flow rate detection result.

[0019] In one embodiment of the present invention, the flow detection is performed based on a flow meter, and the pressure of the storage tank is adjusted based on the flow detection result to control the flow of the fourth gas.

[0020] In one embodiment of the present invention, before the flow rate of the fourth gas is detected, the third one-way valve is used to prevent the fourth gas from flowing back in the direction of being transmitted from the storage tank to the use end.

[0021] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0022] The inert gas recovery method for optical fiber manufacturing described in the present invention does not need to change the structure of the induction furnace, has low cost, and has good variability and versatility; the recovery of the inert gas is controlled twice based on the first set threshold and the second set threshold, thereby improving the recovery purity and recovery efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0024] Figure 1 The present invention is a flowchart of an inert gas recovery method for optical fiber manufacturing in an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of a recovery system designed based on the inert gas recovery method for optical fiber manufacturing in an embodiment of the present invention.

[0026] Description of the Figures in the Specification:

[0027] 10 line areas; 20 public areas;

[0028] 101 induction furnace; 102 collection device; 103 filter; 104 line solenoid valve;

[0029] 201 extraction pump; 202 oxygen sensor; 203 bypass solenoid valve; 204 main solenoid valve; 205 storage tank; 206 first one-way valve; 207 second one-way valve. DETAILED DESCRIPTION

[0030] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0031] In this application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, and can be a fixed connection, a detachable connection, or an integral connection; can be a mechanical connection, or an electrical connection; can be a direct connection, or an indirect connection through an intermediate medium, can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0033] The cost of using inert gas accounts for a large proportion of the total cost of optical fiber manufacturing. Recycling inert gas is an optimization direction in optical fiber manufacturing. However, in actual operation, since the structure of the induction furnace needs to take into account the feeding of the drawing light rod and the output of the optical fiber, its upper and lower parts cannot be completely sealed, which hinders the recovery of inert gas. Existing inert gas recovery is often achieved by changing the structure of the induction furnace, which is costly, poor in variability and versatility; lack of control over the inert gas recovery threshold reduces the recovery purity and efficiency of the inert gas. These problems are particularly obvious when there are a large number of induction furnaces.

[0034] To this end, the present application embodiment provides an inert gas recovery method for optical fiber manufacturing, which is applied to an optical fiber manufacturing workshop with multiple production lines, each of which is equipped with an induction furnace and a line solenoid valve. Figure 1 As shown, including:

[0035] Step S1: collecting the gas output from the bottom annealing tube of the induction furnace to obtain a first gas;

[0036] Step S2: filtering the first gas to obtain a second gas;

[0037] Step S3: controlling the line solenoid valves configured on each of the production lines according to a first set threshold value, and when the first set threshold value is met, the line solenoid valves are opened, and the second gas continues to be transmitted; when the first set threshold value is not met, the line solenoid valves are closed, and the second gas is blocked in the corresponding production line;

[0038] Step S4: uniformly extracting the second gas that continues to be transmitted to obtain a third gas;

[0039] Step S5: When the third gas meets the second set threshold, the third gas is recovered to the storage tank; when the third gas does not meet the second set threshold, the third gas is discharged.

[0040] The present embodiment provides an inert gas recovery method for optical fiber manufacturing, which (1) does not require changing the structure of the induction furnace, has low cost, and has good variability and versatility; (2) controls the recovery of the inert gas twice based on a first set threshold and a second set threshold, thereby improving the recovery purity and recovery efficiency; (3) the more induction furnaces there are, the more obvious the beneficial effects are.

[0041] Next, a method for recovering inert gas for optical fiber manufacturing provided in this embodiment is described in detail. Figure 1 and Figure 2 shown.

[0042] It should be noted that Figure 2 The schematic diagram of the recovery system designed based on the inert gas recovery method for optical fiber manufacturing is shown in FIG. In addition, considering that argon has the advantages of being more abundant in resources, easier to obtain, and lower in cost than other inert gases, this embodiment uses argon to protect graphite parts in optical fiber manufacturing, that is, the object of recovery is argon.

[0043] Step S1: collecting the gas output from the bottom annealing tube of the induction furnace to obtain the first gas.

[0044] Exemplarily, the first gas is obtained by collecting the gas output from the bottom annealing tube of the induction furnace 101 based on the collecting device 102; wherein, there are suction holes on both sides of the collecting device 102, and the collecting device 102 is connected to the bottom annealing tube of the induction furnace 101 through a metal hard tube.

[0045] Step S2: filtering the first gas to obtain a second gas.

[0046] Exemplarily, the second gas is obtained by filtering the first gas based on the filter 103; wherein the filter 103 is connected to the collection device 102, and the filter 103 can remove the ash in the first gas.

[0047] Step S3: Control the line solenoid valve 104 configured on each of the production lines according to the first set threshold value. When the first set threshold value is met, the line solenoid valve 104 is opened and the second gas continues to be transmitted; when the first set threshold value is not met, the line solenoid valve 104 is closed and the second gas is blocked in the corresponding production line.

[0048] For example, please refer to Figure 2 As shown, the line area 10 includes a plurality of the production lines.

[0049] Optionally, after filtering the first gas to obtain the second gas, the first set threshold is set according to the rated power of the corresponding induction furnace 101 on the production line, or the first set threshold is set according to the remaining length of the drawing polished rods waiting to be put into the corresponding induction furnace 101 on the production line.

[0050] Preferably, when the operating power of the corresponding induction furnace 101 on the production line is less than 20% of the rated power, or the remaining length of the drawn polished rods waiting to be put into the corresponding induction furnace 101 on the production line is less than 200 kilometers, the corresponding line solenoid valve 104 on the production line is closed; when the operating power of the corresponding induction furnace 101 on the production line is not less than 20% of the rated power, or the remaining length of the drawn polished rods waiting to be put into the corresponding induction furnace 101 on the production line is not less than 200 kilometers, the corresponding line solenoid valve 104 on the production line is opened.

[0051] Step S4: uniformly extracting the second gas that continues to be transmitted to obtain the third gas.

[0052] For example, please refer to Figure 2 As shown, when step S4 is executed, the public area 20 is entered, and the public area 20 centrally recovers the gas transmitted on each production line in the line area 10.

[0053] Exemplarily, the third gas is obtained by uniformly extracting the second gas continuously transmitted by each production line based on the extraction pump 201 .

[0054] Furthermore, as the number of production lines increases, it is necessary to select a higher-power extraction pump as the extraction pump 201 .

[0055] Step S5: When the uniformly extracted gas meets the second set threshold, the third gas is recovered to the storage tank; when the uniformly extracted gas does not meet the second set threshold, the third gas is discharged.

[0056] For example, please refer to Figure 2As shown, when the third gas meets the second set threshold, the bypass solenoid valve 203 is closed and the main solenoid valve 204 is opened, and the third gas is recovered to the storage tank 205; conversely, the bypass solenoid valve 203 is opened and the main solenoid valve 204 is closed, and the third gas is discharged; wherein the bypass solenoid valve 203 is connected to the outside of the system, and the third gas can be discharged.

[0057] Optionally, the second set threshold is set according to the oxygen content of the third gas; and the oxygen content of the third gas is detected based on the oxygen sensor 202 .

[0058] Preferably, when the oxygen content of the third gas does not exceed 0.4%, the third gas is recovered to the storage tank 205; when the oxygen content of the third gas exceeds 0.4%, the third gas is discharged.

[0059] Preferably, after the second gas that is continuously transmitted is uniformly extracted to obtain the third gas, the first one-way valve 206 is used to prevent the third gas from flowing back in a recovery direction or an external discharge direction.

[0060] Specifically, the first check valve 206 can prevent external air from mixing into the interior through the bypass solenoid valve 203 , and can also prevent the argon gas recovered from the storage tank 205 from flowing back.

[0061] Preferably, when the third gas meets the second set threshold, before the third gas is recovered to the storage tank, the second one-way valve 207 is used to prevent the third gas from flowing back in the recovery direction.

[0062] Specifically, the second one-way valve 207 can further prevent the argon gas recovered in the storage tank 205 from flowing back.

[0063] Furthermore, as the number of production lines increases, it is necessary to select a storage tank with a larger volume as the above-mentioned storage tank 205.

[0064] Step S6: The third gas recovered to the storage tank 205 is transmitted and utilized to obtain a fourth gas; wherein, the flow rate of the fourth gas is detected, and the flow rate of the fourth gas transmitted from the storage tank to the user end is controlled based on the flow rate detection result.

[0065] Furthermore, the flow detection is performed based on a flow meter, and the pressure of the storage tank is adjusted based on the flow detection result to control the flow of the fourth gas.

[0066] Specifically, the on-duty personnel can perform pressure regulation control according to the flow detection results, or they can hand over the pressure control together with the line solenoid valve 104, the bypass solenoid valve 203, and the main solenoid valve 204 to ensure that the pressure difference in the storage tank 205 and the flow rate of the fourth gas are within the normal range.

[0067] Furthermore, before the flow rate of the fourth gas is detected, the third one-way valve is used to prevent the fourth gas from flowing back in the direction from the storage tank to the use end; this can prevent the argon gas from flowing back to the storage tank 205 when using argon gas.

[0068] The inert gas recovery method for optical fiber manufacturing described in this embodiment only requires the installation of a control system, which controls the line solenoid valves 104 on each production line in the line area 10 based on a first set threshold, and controls the bypass solenoid valve 203 and the main solenoid valve 204 in the public area 20 based on a second set threshold. While realizing intelligent automation to reduce manual intervention, it can achieve centralized recovery to improve recovery efficiency.

[0069] Exemplarily, the line area 10 includes 12 production lines, the first set threshold is 20% of the rated power of the induction furnace or the remaining length of the drawn light rod is 200 kilometers, the second set threshold is the oxygen content of 0.4%, and the achievable argon recovery rate is 40%, that is, when the argon flow rate entering the induction furnace 101 is 10L / min, the argon flow rate that can be used from the storage tank 205 is 4L / min.

[0070] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0071] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1A device that provides the functions specified in a block or multiple blocks.

[0072] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0073] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0074] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A method for recovering inert gas for optical fiber manufacturing, applied to an optical fiber manufacturing workshop with multiple production lines, each of which is equipped with an induction furnace and a line solenoid valve, characterized in that: include: Step S1: collecting the gas output from the bottom annealing tube of the induction furnace to obtain a first gas; Step S2: filtering the first gas to obtain a second gas; Step S3: controlling the line solenoid valves configured on each of the production lines according to a first set threshold value, and when the first set threshold value is met, the line solenoid valves are opened, and the second gas continues to be transmitted; when the first set threshold value is not met, the line solenoid valves are closed, and the second gas is blocked in the corresponding production line; Step S4: uniformly extracting the second gas that continues to be transmitted to obtain a third gas; Step S5: When the third gas meets the second set threshold, the third gas is recovered to the storage tank; when the third gas does not meet the second set threshold, the third gas is discharged.

2. The inert gas recovery method for optical fiber manufacturing according to claim 1, characterized in that: After filtering the first gas to obtain the second gas, the first set threshold is set according to the rated power of the corresponding induction furnace on the production line, or the first set threshold is set according to the remaining length of the wire drawing polished rods waiting to be put into the corresponding induction furnace on the production line.

3. The inert gas recovery method for optical fiber manufacturing according to claim 2, characterized in that: When the operating power of the corresponding induction furnace on the production line is less than 20% of the rated power, or the remaining length of the wire drawing polished rod waiting to be put into the corresponding induction furnace on the production line is less than 200 kilometers, close the corresponding line solenoid valve on the production line; When the operating power of the corresponding induction furnace on the production line is not less than 20% of the rated power, or the remaining length of the wire drawing polished rods waiting to be put into the corresponding induction furnace on the production line is not less than 200 kilometers, the corresponding line solenoid valve on the production line is opened.

4. The inert gas recovery method for optical fiber manufacturing according to claim 1, characterized in that: The second set threshold is set according to the oxygen content of the third gas.

5. The inert gas recovery method for optical fiber manufacturing according to claim 4, characterized in that: When the oxygen content of the third gas does not exceed 0.4%, the third gas is recovered to a storage tank; when the oxygen content of the third gas exceeds 0.4%, the third gas is discharged.

6. The inert gas recovery method for optical fiber manufacturing according to claim 1, characterized in that: After the second gas that continues to be transmitted is uniformly extracted to obtain the third gas, the first one-way valve is used to prevent the third gas from flowing back in the recovery direction or the discharge direction.

7. The inert gas recovery method for optical fiber manufacturing according to claim 1, characterized in that: When the third gas meets the second set threshold, before the third gas is recovered to the storage tank, the second one-way valve prevents the third gas from flowing back in the recovery direction.

8. The inert gas recovery method for optical fiber manufacturing according to claim 1, characterized in that: The method further includes step S6: transmitting and utilizing the third gas recovered to the storage tank to obtain a fourth gas; wherein the flow rate of the fourth gas is detected, and the flow rate of the fourth gas transmitted from the storage tank to the user end is controlled based on the flow rate detection result.

9. The inert gas recovery method for optical fiber manufacturing according to claim 8, characterized in that: The flow rate detection is performed based on a flow meter, and the pressure of the storage tank is adjusted based on the flow rate detection result to control the flow rate of the fourth gas.

10. The inert gas recovery method for optical fiber manufacturing according to claim 8, characterized in that: Before the flow rate of the fourth gas is detected, the third one-way valve is used to prevent the fourth gas from flowing back in the direction of being transmitted from the storage tank to the use end.

Images