CN118005262A - Device and method for controlling longitudinal temperature zone of optical fiber preform sintering furnace on line - Google Patents
Device and method for controlling longitudinal temperature zone of optical fiber preform sintering furnace on line Download PDFInfo
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- CN118005262A CN118005262A CN202410254081.1A CN202410254081A CN118005262A CN 118005262 A CN118005262 A CN 118005262A CN 202410254081 A CN202410254081 A CN 202410254081A CN 118005262 A CN118005262 A CN 118005262A
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- temperature
- guide rod
- optical fiber
- fiber preform
- measuring element
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- 239000013307 optical fiber Substances 0.000 title claims abstract description 54
- 238000005245 sintering Methods 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000010438 heat treatment Methods 0.000 claims abstract description 16
- 238000009826 distribution Methods 0.000 claims abstract description 14
- 238000013480 data collection Methods 0.000 claims abstract description 6
- 238000004519 manufacturing process Methods 0.000 claims description 29
- 238000012544 monitoring process Methods 0.000 claims description 9
- 238000012360 testing method Methods 0.000 claims description 9
- 238000004017 vitrification Methods 0.000 claims description 7
- 238000005906 dihydroxylation reaction Methods 0.000 claims description 5
- 230000003044 adaptive effect Effects 0.000 claims description 3
- 238000012937 correction Methods 0.000 claims description 3
- 238000003780 insertion Methods 0.000 claims description 3
- 230000037431 insertion Effects 0.000 claims description 3
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 claims description 3
- PXXKQOPKNFECSZ-UHFFFAOYSA-N platinum rhodium Chemical compound [Rh].[Pt] PXXKQOPKNFECSZ-UHFFFAOYSA-N 0.000 claims description 3
- 239000000835 fiber Substances 0.000 claims description 2
- 230000001276 controlling effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 3
- 238000009529 body temperature measurement Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000002950 deficient Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000009477 glass transition Effects 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
- C03B5/24—Automatically regulating the melting process
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
The invention discloses an on-line control device and method for a longitudinal temperature zone of an optical fiber preform sintering furnace, wherein the on-line control device comprises a furnace core tube, a heating device, a guide rod, a temperature measuring element, a motor and data collecting equipment; the heating device is arranged at the periphery of the furnace core tube and is used for heating the furnace core tube; the middle part of the guide rod is of a hollow structure, the upper end of the guide rod is connected with a motor, and the motor can drive the guide rod to rotate; the optical fiber preform rod is hung in the furnace core tube through the guide rod; the temperature measuring element is arranged in the hollow structure of the guide rod; the temperature measuring element is in signal connection with the data collection device. The invention can realize the automatic on-line control of the longitudinal temperature zone of the optical fiber preform sintering furnace, improve the process temperature accuracy, solve the influence on the preform when the temperature field distribution is deviated, and improve the quality and uniformity of the preform product.
Description
Technical Field
The invention belongs to the technical field of optical fiber manufacturing, and particularly relates to an on-line control device and method for a longitudinal temperature zone of an optical fiber preform sintering furnace.
Background
The optical fiber perform is sintered, a high-temperature environment is provided by adopting a resistance furnace or an induction furnace, and the perform in the furnace core tube is subjected to dehydroxylation and vitrification in a heat transfer and heat radiation mode; the process has higher requirements on the production temperature control precision.
The optical fiber preform sintering equipment is used for monitoring the temperature of a fixed position in a heater in general cases; the mode is widely applied to various sintering furnaces due to the simple structure adopted by the mode. The temperature in the furnace core tube is generally checked by using a thermocouple when the sintering furnace is stopped, and the actual temperature control has deviation because the temperature is different from the actual production environment in the test process and the preform absorbs heat and the gas chemical reaction absorbs heat in the production process. Secondly, because the temperature in the heater and the furnace core pipe has deviation, when the temperature changes, the actual temperature changes at two positions are irregular, and the temperature in the furnace core pipe can not be accurately controlled by regulating and controlling the temperature at the heater. Meanwhile, the temperature field distribution condition cannot be known in a fixed position monitoring mode, and in the actual optical fiber preform production process, if the highest temperature in a furnace core tube and the temperature field distribution deviate, the fixed position monitoring mode cannot accurately identify the highest temperature and the temperature field distribution, which may result in: 1) The attenuation of the optical fiber at the wavelength of 1383nm can be obviously increased due to insufficient local dehydroxylation temperature; 2) The glass transition temperature is deviated, and the appearance of the preform rod is defective after glass transition; 3) The temperature field changes, the refractive index of the two ends of the preform rod does not meet the requirement, and the appearance of the preform rod is defective after vitrification. If the above problems occur, the loss of the production process increases, which is disadvantageous for mass production of the optical fiber preform.
In summary, a method for detecting the temperature and the temperature field distribution change in the furnace core tube and automatically correcting the temperature and the temperature field distribution change in time on the premise of not influencing the production of the optical fiber preform and guaranteeing the tightness of equipment needs to be developed.
Chinese patent, grant No. CN 211141894U, provides a sintering apparatus and method for monitoring the diameter of a preform in real time, thereby controlling the temperature and speed in real time. The method can regulate and control the temperature of the fixed position in real time, but is only limited to be applied to the diameter shrinkage stage of the preform, and the application condition is limited.
Chinese patent, issued No. CN 203668232U, provides a sintering apparatus for optical fiber preforms, which uses a laser feedback control system to adjust the temperature of the sintering furnace in real time during sintering. The thermocouple in the sintering equipment is penetrated in the heat insulation material of the sintering furnace, and the laser transmitter and the laser receiver are arranged at two sides of the quartz furnace core tube; the method uses a laser control system to monitor the vitrification degree of the sintered preform below the heater to adjust the temperature in real time. The method cannot detect the preform before the preform is sintered and falls into a laser system area, has obvious abnormal response hysteresis, and is only suitable for the vitrification stage of the preform and cannot monitor the actual situation of a high Wen Ouwen field.
Chinese patent, publication No. CN 110104946A, provides a structure of optical fiber preform sintering equipment. The structure does not mention how the temperature of the warm zone is controlled.
Chinese patent, grant publication No. CN 209537309U, provides a dehydration sintering furnace structure for optical fiber preforms. The temperature measurement and temperature control are carried out by adding a temperature sensor in the sintering furnace heater, and the temperature can be monitored only at a fixed position, so that the problem that the temperature field change cannot be detected in time still exists.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide the device and the method for controlling the longitudinal temperature zone of the optical fiber perform sintering furnace on line, which can realize the automatic on-line control of the longitudinal temperature zone of the optical fiber perform sintering furnace, improve the accuracy of process temperature, solve the influence on the perform when the temperature field distribution is deviated, and improve the quality and uniformity of the preform product.
In order to achieve the technical purpose and the technical effect, the invention is realized by the following technical scheme:
The invention provides an on-line control device for a longitudinal temperature zone of an optical fiber preform sintering furnace, which comprises a furnace core tube, a heating device, a guide rod, a temperature measuring element, a motor and data collecting equipment;
The heating device is arranged at the periphery of the furnace core tube and is used for heating the furnace core tube;
the middle part of the guide rod is of a hollow structure, the upper end of the guide rod is connected with a motor, and the motor can drive the guide rod to rotate; the optical fiber preform rod is hung in the furnace core tube through the guide rod;
the temperature measuring element is arranged in the hollow structure of the guide rod;
The temperature measuring element is in signal connection with the data collection device.
Further, the upper end of the temperature measuring element is fixedly connected with the guide rod, and the temperature measuring element is connected with the data collecting device through an electric slip ring.
Further, the rotating part of the electric slip ring is fixedly connected with the guide rod, and the fixed part of the electric slip ring is fixedly connected to the data collecting equipment; and an opening is formed in the upper part of the guide rod, and a lead wire of the temperature measuring element passes through the opening of the guide rod and is connected to the electric slip ring.
Further, the length of the guide rod is larger than the insertion depth of the temperature measuring element in the furnace core pipe.
Preferably, the temperature measuring element is a thermocouple.
Furthermore, the thermocouple is a platinum-rhodium thermocouple, and the adaptive temperature range is 0-1800 ℃.
Furthermore, the guide rod is a high-temperature-resistant guide rod.
Further, the motor can move up and down to drive the guide rod and the temperature measuring element to move up and down.
In another aspect, the present invention provides an on-line control method for a longitudinal temperature zone of an optical fiber preform sintering furnace, which is performed based on the above-mentioned on-line control device, and includes:
in the production process of the optical fiber preform, a guide rod is moved and rotated by a motor, the temperature in a furnace core tube is tested on line in real time by using a temperature measuring element arranged in the guide rod, test data are transmitted to data collection equipment, a database is formed, and a reference model is generated by fitting;
before optical fiber perform rod production, executing a self-checking program, testing a temperature field in a furnace core tube in a mode of moving a motor, and automatically correcting an initial set temperature by calculating a maximum temperature change amplitude when the maximum temperature in the furnace core tube changes based on a reference model; when the temperature field distribution in the furnace core tube changes, automatically calculating and correcting the process position of the fiber preform for dehydroxylation and vitrification by calculating the position of the boundary point of the effective temperature field;
In the actual production process of the optical fiber preform, the actual temperature is automatically corrected by comparing the deviation of the real-time monitoring temperature and the existing reference model, and the reference model is automatically optimized by the data in the existing actual production process; and when the automatic temperature deviation correction continuously cannot reach the expected temperature, automatically stopping production.
The invention has the beneficial effects that:
The temperature is monitored in real time in a mode of embedding a temperature measuring element in a guide rod used in optical fiber preform sintering equipment; the motor realizes the movement and rotation of the guide rod, and can achieve the effect of synchronously moving the temperature measuring element, thereby realizing the automatic on-line control of the whole longitudinal temperature zone of the optical fiber preform sintering furnace, improving the accuracy of the process temperature and the quality and uniformity of the preform product;
The invention can automatically correct the process position by monitoring the data; the method solves the problem of influence on the preform when the temperature field distribution is deviated, and improves the quality and uniformity of the preform product;
the invention adopts the electric slip ring to connect the temperature measuring element, so as to realize the temperature measurement of the temperature measuring element in a rotating state in the production process;
The invention solves the problem that the temperature of the heating device and the temperature in the furnace core tube are deviated due to the fact that the temperature is monitored in the heating device in the prior art, and improves the accuracy of temperature control;
the invention solves the problem that the traditional method for monitoring the fixed position in the heating device can not detect the temperature field distribution, and improves the flexibility of the test position;
The device does not affect the sealing structure of equipment in the use process, and has no influence on the production environment of the optical fiber preform.
Drawings
FIG. 1 is a schematic diagram of a longitudinal temperature zone on-line control device for an optical fiber preform sintering furnace according to the present invention.
Fig. 2 is a flow chart of the on-line control method of the present invention executing the self-checking procedure.
Fig. 3 is a schematic flow chart of the on-line control method of the present invention in the optical fiber preform manufacturing process.
FIG. 4 is a schematic diagram of the adjustment of the on-line control method of the present invention when the maximum temperature in the core tube is changed.
FIG. 5 is a schematic diagram of the on-line control method of the present invention for adjusting the temperature field distribution in the furnace core tube.
Fig. 6 is a schematic diagram showing real-time adjustment of the on-line control method of the present invention in the production process of an optical fiber preform.
In the figure, 1: a furnace core tube; 2: a heating device; 3: a guide rod; 4: a temperature measuring element; 5: a motor; 6: an electrical slip ring.
Detailed Description
The following description of the embodiments of the present invention will be made more apparent and fully by reference to the accompanying drawings, in which it is shown, by way of illustration, only some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The preferred embodiment of the on-line control device for the longitudinal temperature zone of the optical fiber preform sintering furnace shown in FIG. 1 comprises a furnace core tube 1, a heating device 2, a guide rod 3, a temperature measuring element 4, a motor 5 and data collecting equipment;
The heating device 2 is arranged at the periphery of the furnace core tube 1 and is used for heating the furnace core tube 1 to realize sintering of the optical fiber preform;
the bottom end of the guide rod 3 is solid, the middle part of the rest part is of a hollow structure, the upper end of the guide rod 3 is connected with a motor 5, and the motor 5 can drive the guide rod 3 to rotate; the optical fiber preform is hung in the furnace core tube 1 through the guide rod 3;
the temperature measuring element 4 is arranged in the hollow structure of the guide rod 3;
the temperature measuring element 4 is in signal connection with the data collection device.
Specifically, the upper end of the temperature measuring element 4 is fixedly connected with the guide rod 3, and the temperature measuring element 4 is connected with the data collecting device through an electric slip ring 6. More specifically, the rotating part of the electric slip ring 6 is fixedly connected with the guide rod 3, and the fixed part of the electric slip ring 6 is fixedly connected to data collecting equipment near the motor; an opening is formed in the upper portion of the guide rod 3, and a lead wire of the temperature measuring element 4 passes through the opening of the guide rod 3 and is connected to the electric slip ring 6. The structure of the electric slip ring 6 can meet the requirement of rotation of the guide rod in the production process of the optical fiber preform rod, and meanwhile, the structure does not influence the overall tightness of the equipment.
The length of the guide rod 3 is larger than the insertion depth of the temperature measuring element 4 in the furnace core pipe 1 so as to test the temperature field distribution condition in the furnace core pipe.
In this embodiment, the temperature measuring element 4 is a thermocouple, and the thermocouple is a platinum-rhodium thermocouple, and the adaptive temperature range is 0-1800 ℃, so that the temperature required by the production of the optical fiber preform can be matched. The thermocouple is fixed at the hollow part of the guide rod through the shell made of high-temperature-resistant nonmetallic materials.
The guide rod 3 is made of a material with high temperature resistance and stable chemical property, so that the influence of the reaction of the guide rod with gas in the sintering furnace at high temperature on the quality of the core rod is avoided, and meanwhile, the high temperature resistance material can prevent the guide rod from deforming at high temperature for a long time, so that the replacement frequency is reduced, and the cost is lowered;
The motor 5 can move up and down under external control to drive the guide rod 3 and the temperature measuring element 4 to move up and down.
As shown in fig. 2 to 6, the method for controlling the longitudinal temperature zone of the optical fiber preform sintering furnace on line based on the on-line control device comprises the following steps:
In the production process of the optical fiber preform, the guide rod 3 is moved and rotated by the motor 5, the temperature in the furnace core tube 1 is tested on line in real time by using the temperature measuring element 4 arranged in the guide rod 3, test data are transmitted to the data collecting equipment, a database is formed, and a reference model is generated by fitting;
Before the optical fiber preform is produced, executing a self-checking program, testing the temperature field in the furnace core tube by means of a mobile motor, and automatically correcting the initial set temperature by calculating the variation amplitude (delta T) of the highest temperature when the highest temperature in the furnace core tube is changed based on a reference model as shown in fig. 4; when the temperature field distribution in the furnace core tube changes, as shown in fig. 5, the process positions for correcting the dehydroxylation and vitrification of the optical fiber preform are automatically calculated by calculating the positions of the boundary points of the effective temperature field;
in the actual production process of the optical fiber preform, the actual temperature is automatically corrected by comparing the deviation of the real-time monitoring temperature and the existing reference model, as shown in fig. 6, and the reference model is automatically optimized by the data in the existing actual production process, and the optimized reference model can be used as the actual reference model for the next optical fiber preform production; and when the automatic temperature deviation correction continuously cannot reach the expected temperature, automatically stopping production.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.
Claims (9)
1. The on-line control device for the longitudinal temperature zone of the optical fiber preform sintering furnace is characterized by comprising a furnace core tube, a heating device, a guide rod, a temperature measuring element, a motor and data collecting equipment;
The heating device is arranged at the periphery of the furnace core tube and is used for heating the furnace core tube;
the middle part of the guide rod is of a hollow structure, the upper end of the guide rod is connected with a motor, and the motor can drive the guide rod to rotate; the optical fiber preform rod is hung in the furnace core tube through the guide rod;
the temperature measuring element is arranged in the hollow structure of the guide rod;
The temperature measuring element is in signal connection with the data collection device.
2. The on-line control device for the longitudinal temperature zone of the optical fiber preform sintering furnace according to claim 1, wherein the upper end of the temperature measuring element is fixedly connected with the guide rod, and the temperature measuring element is connected with the data collecting equipment through an electric slip ring.
3. The on-line control device for the longitudinal temperature zone of the optical fiber preform sintering furnace according to claim 2, wherein the rotating part of the electric slip ring is fixedly connected with the guide rod, and the fixing part of the electric slip ring is fixedly connected to the data collecting equipment; and an opening is formed in the upper part of the guide rod, and a lead wire of the temperature measuring element passes through the opening of the guide rod and is connected to the electric slip ring.
4. The device for on-line control of the longitudinal temperature zone of an optical fiber preform sintering furnace according to claim 1, wherein the length of the guide rod is longer than the insertion depth of the temperature measuring element in the furnace core tube.
5. The device for on-line control of the longitudinal temperature zone of an optical fiber preform sintering furnace according to claim 1, wherein the temperature measuring element is a thermocouple.
6. The on-line control device for the longitudinal temperature zone of the optical fiber preform sintering furnace according to claim 5, wherein the thermocouple is a platinum-rhodium thermocouple, and the adaptive temperature range is 0-1800 ℃.
7. The device for on-line control of the longitudinal temperature zone of an optical fiber preform sintering furnace according to claim 1, wherein the guide rod is a high temperature resistant guide rod.
8. The device for on-line control of the longitudinal temperature zone of an optical fiber preform sintering furnace according to claim 1, wherein the motor is capable of moving up and down to drive the guide rod and the temperature measuring element to move up and down.
9. An on-line control method for a longitudinal temperature zone of an optical fiber preform sintering furnace, which is characterized by being performed based on the on-line control device according to any one of claims 1 to 8, and comprising:
in the production process of the optical fiber preform, a guide rod is moved and rotated by a motor, the temperature in a furnace core tube is tested on line in real time by using a temperature measuring element arranged in the guide rod, test data are transmitted to data collection equipment, a database is formed, and a reference model is generated by fitting;
before optical fiber perform rod production, executing a self-checking program, testing a temperature field in a furnace core tube in a mode of moving a motor, and automatically correcting an initial set temperature by calculating a maximum temperature change amplitude when the maximum temperature in the furnace core tube changes based on a reference model; when the temperature field distribution in the furnace core tube changes, automatically calculating and correcting the process position of the fiber preform for dehydroxylation and vitrification by calculating the position of the boundary point of the effective temperature field;
In the actual production process of the optical fiber preform, the actual temperature is automatically corrected by comparing the deviation of the real-time monitoring temperature and the existing reference model, and the reference model is automatically optimized by the data in the existing actual production process; and when the automatic temperature deviation correction continuously cannot reach the expected temperature, automatically stopping production.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410254081.1A CN118005262A (en) | 2024-03-06 | 2024-03-06 | Device and method for controlling longitudinal temperature zone of optical fiber preform sintering furnace on line |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410254081.1A CN118005262A (en) | 2024-03-06 | 2024-03-06 | Device and method for controlling longitudinal temperature zone of optical fiber preform sintering furnace on line |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118005262A true CN118005262A (en) | 2024-05-10 |
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ID=90950478
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410254081.1A Pending CN118005262A (en) | 2024-03-06 | 2024-03-06 | Device and method for controlling longitudinal temperature zone of optical fiber preform sintering furnace on line |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118005262A (en) |
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2024
- 2024-03-06 CN CN202410254081.1A patent/CN118005262A/en active Pending
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