Optical fiber temperature control method, system and device

Abstract

The invention discloses an optical fiber temperature control method, system and device, and relates to the technical field of optical information. The optical fiber temperature control method comprises the following steps: acquiring an optical fiber temperature, a coating temperature and an optical fiber drawing rate; and if the absolute value of the difference value between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, adjusting a cooling parameter according to the current optical fiber drawing rate, so that the absolute value of the difference value between the optical fiber temperature and the coating temperature is less than the first temperature threshold. The absolute value of the difference value between the optical fiber temperature and the coating temperature is smaller than the first temperature threshold value and is controlled within the range smaller than the first temperature threshold value, the deviation between the optical fiber temperature and the coating temperature can be reduced, and temperature fluctuation is reduced. And the quality problems of glue overflowing, bead stringing, fine threads, coating fluctuation and the like in the coating process are reduced.

Description

Technical Field

[0001] The present application relates to the field of optical information technology, and in particular to an optical fiber temperature control method, system and device. Background Art

[0002] During the fiber drawing process, the fiber is at a high temperature when it comes out of the drawing furnace and carries a lot of heat. At this time, before coating, the temperature of the fiber needs to be lowered to a range suitable for coating. Generally, the temperature is controlled in a specific range by a cooling device to ensure that the coating material can adhere normally. When the fiber temperature deviates greatly from the coating temperature, it will cause coating abnormalities, such as glue oozing, beads, thin lines, coating fluctuations and other quality problems, affecting the quality of the fiber. Summary of the invention

[0003] The present application provides an optical fiber temperature control method, system and device to solve the existing quality problems such as coating abnormality, such as glue oozing, beading, thin lines, coating fluctuations, etc., when the optical fiber temperature deviates greatly from the coating temperature.

[0004] In a first aspect, the present application provides a method for controlling the temperature of an optical fiber, comprising the following steps:

[0005] Obtain the fiber temperature, coating temperature and fiber drawing rate;

[0006] If the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameters are adjusted according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold.

[0007] The present application obtains the fiber temperature, coating temperature and fiber drawing rate, and when the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, adjusts the cooling parameters according to the current fiber drawing rate, so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold, so that the absolute value of the difference between the fiber temperature and the coating temperature is controlled within the range less than the first temperature threshold, which can reduce the deviation between the fiber temperature and the coating temperature, reduce temperature fluctuations, and reduce quality problems such as glue bubbling, beading, thin lines, and coating fluctuations during the coating process. Among them, the first temperature threshold can be 3 to 8 ° C. When - the first temperature threshold < T1-T2 < the first temperature threshold, the fiber temperature does not need to be adjusted; when T1-T2≤- the first temperature threshold, that is, the fiber temperature is lower than the coating temperature, the fiber temperature is increased so that the temperature difference meets the requirements. When T1-T2≥ the first temperature threshold, that is, the fiber temperature is higher than the coating temperature, the fiber temperature is reduced so that the temperature difference meets the requirements.

[0008] It should be noted that the cooling parameters that need to be controlled are different when the optical fiber drawing speed is different to achieve the same cooling temperature. This is because the faster the optical fiber drawing speed, the more heat it brings per unit time and the more cooling capacity is required. The slower the optical fiber drawing speed, the less heat it brings per unit time and the less cooling capacity is required. Therefore, by adjusting the cooling parameters according to the current optical fiber drawing speed, the optical fiber temperature can be accurately controlled and the deviation between the optical fiber temperature and the coating temperature can be reduced.

[0009] In some embodiments, the cooling parameters include at least one of helium temperature, helium flow rate, and coolant temperature. Traditional cooling methods such as natural cooling or air cooling have extremely low cooling efficiency under high-speed wire drawing conditions and cannot meet the requirements for rapid cooling of optical fibers. Cold pipe cooling technology is mainly based on the principle of heat conduction and is usually made of materials with high thermal conductivity, such as copper and other metals. When the high-temperature optical fiber passes through the cold pipe, the optical fiber directly contacts the helium in the cold pipe for heat exchange, and the heat is transferred to the cold pipe. A coolant circulation system can be set inside the cold pipe or a special refrigeration structure can be used to maintain the low temperature of the cold pipe, so that heat is continuously transferred from the optical fiber to the cold pipe and taken away. Therefore, the temperature of the optical fiber can be controlled by adjusting the helium temperature, helium flow rate, and coolant temperature.

[0010] In some embodiments, the optical fiber temperature is T1, the coating temperature is T2, and the first temperature threshold is ΔT. If T1-T2≥ΔT, it satisfies:

[0011] Helium temperature regulation rate = first reference regulation rate * (T1-T2); and / or,

[0012] Helium flow rate adjustment rate = second reference adjustment rate * (T1-T2); and / or,

[0013] Coolant temperature adjustment rate = third reference adjustment rate * (T1-T2);

[0014] Among them, the first reference adjustment rate, the second reference adjustment rate and the third reference adjustment rate are coefficients related to the optical fiber drawing rate.

[0015] By regulating the helium temperature, helium flow rate and coolant temperature according to the first reference regulating rate, the second reference regulating rate and the third reference regulating rate, which are coefficients related to the optical fiber drawing rate, the optical fiber temperature can be precisely controlled, and the absolute value of the difference between the optical fiber temperature and the coating temperature can be reduced. In particular, when the optical fiber drawing rate changes, the cooling parameters of the optical fiber can be precisely regulated based on the change in the optical fiber drawing rate, so as to achieve precise control of the optical fiber temperature.

[0016] In some embodiments, the first reference adjustment rate is 0.1-0.5°C / min. Within this range, the first reference adjustment rate can adapt to the control of optical fiber temperature at different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature; and / or,

[0017] The second reference adjustment rate is 0.05 to 0.25 L / min. Within this range, the second reference adjustment rate can adapt to the control of the optical fiber temperature at different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature; and / or,

[0018] The third reference adjustment rate is 0.1-0.5°C / min. Within this range, the third reference adjustment rate can adapt to the control of optical fiber temperature under different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0019] In some embodiments, the adjustment range of the coolant temperature is -20°C to 20°C. Within this range, the adjustment range of the coolant temperature can adapt to the control of the optical fiber temperature at different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature; and / or,

[0020] The adjustment range of the helium temperature is -20°C to 20°C. Within this range, the adjustment range of the helium temperature can adapt to the control of the optical fiber temperature at different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature; and / or,

[0021] The adjustment range of the helium flow rate is 0 to 20 L / min. Within this range, the adjustment range of the helium flow rate can adapt to the control of the optical fiber temperature at different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0022] In some embodiments, if the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, adjusting the cooling parameter according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold, then adjusting the cooling parameter according to the current fiber drawing rate includes:

[0023] Establish correlation curves among different optical fiber drawing rates, different coolant temperatures, different helium temperatures, different helium flow rates and different optical fiber temperatures, and obtain target coolant temperatures, target helium temperatures and target helium flow rates corresponding to different optical fiber temperatures at different optical fiber drawing rates;

[0024] According to the target coolant temperature, the target helium temperature and the target helium flow rate, the current coolant temperature, the current helium temperature and the current helium flow rate are adjusted.

[0025] By introducing Fourier's law of heat conduction, Newton's law of cooling, convection heat dissipation, and Stefan-Boltzmann's law, a cooling simulation model can be established to obtain the relationship between the coolant temperature, helium temperature, helium flow process parameters and the fiber temperature at different fiber drawing speeds. The fiber temperature can be controlled within a suitable range by presetting the process in advance. The parameters are written into the PLC system and associated with the fiber drawing speed. In actual production, by obtaining the fiber drawing speed and the current fiber temperature, the appropriate coolant temperature, helium temperature, and helium flow can be quickly selected for adjustment, and the fiber temperature can be quickly and accurately regulated, thereby reducing the deviation between the fiber temperature and the coating temperature.

[0026] In some embodiments, the optical fiber drawing rate is 1000m / min to 4000m / min. The optical fiber drawing rate within this range is a high-speed drawing process. In the high-speed drawing process, the optical fiber temperature and the coating temperature are more likely to have a large deviation. The optical fiber temperature control method at this drawing rate has a more significant effect on the optical fiber temperature control effect.

[0027] In a second aspect, the present application provides an optical fiber temperature control system, comprising:

[0028] A drawing device, used for drawing the optical fiber preform into an optical fiber;

[0029] A cooling device, provided at the outlet of the drawing device, for cooling the optical fiber;

[0030] A measuring device for measuring the optical fiber temperature, the coating temperature and the optical fiber drawing rate;

[0031] A coating device, disposed at the outlet of the cooling device, for coating the surface of the optical fiber; and

[0032] The regulating device is communicatively connected to the cooling device, and is used to adjust the cooling parameters according to the current drawing rate of the optical fiber if the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold.

[0033] By obtaining the fiber temperature, coating temperature and fiber drawing rate, when the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameter is adjusted according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold, so that the absolute value of the difference between the fiber temperature and the coating temperature is controlled within a range less than the first temperature threshold, which can reduce the deviation between the fiber temperature and the coating temperature, improve temperature fluctuation, and reduce the quality problems such as glue oozing, beading, thin lines, coating fluctuations, etc. during the coating process. Among them, the first temperature threshold can be 3 to 8°C.

[0034] By improving the quality problem caused by the large deviation between the fiber temperature and the coating temperature after the fiber is cooled during the high-speed drawing process, optimizing the cooling system, establishing a fiber cooling control system, and realizing fiber temperature control through PLC adjustment, the mismatch between the fiber temperature and the coating temperature during the high-speed drawing process is controlled.

[0035] In some embodiments, the measuring device includes a temperature measuring device, which includes a cold pipe joint and an infrared temperature detection device. The cold pipe joint is used to connect the cooling pipe of the cooling device and the coating device. The cold pipe joint is provided with a circular hole, and the infrared temperature detection device measures the temperature of the optical fiber through the circular hole.

[0036] The temperature of the optical fiber can be measured through the cold pipe joint and the round hole on the cold pipe joint to improve the accuracy of optical fiber temperature control. The coating temperature and optical fiber temperature signals can be connected to the system through PLC.

[0037] The cooling device can be a hollow metal tube with an interlayer, in which circulating cooling water is injected. The temperature of the cooling tube is adjusted by a water bath, and the temperature signal is connected to the system by a PLC. The cooling gas helium is introduced from the bottom of the cooling tube. The temperature and flow of the cooling gas can be adjusted by a temperature control device and a flow meter, and the temperature and flow signals are connected to the system through a PLC.

[0038] In a third aspect, the present application provides an optical fiber temperature control device, comprising:

[0039] An acquisition unit, used to acquire the optical fiber temperature, the coating temperature and the optical fiber drawing rate;

[0040] A control unit is used to adjust the cooling parameters according to the current optical fiber drawing rate if the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold.

[0041] By obtaining the fiber temperature, coating temperature and fiber drawing rate, when the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameter is adjusted according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold, so that the absolute value of the difference between the fiber temperature and the coating temperature is controlled within a range less than the first temperature threshold, which can reduce the deviation between the fiber temperature and the coating temperature, improve temperature fluctuation, and reduce the quality problems such as glue oozing, beading, thin lines, coating fluctuations, etc. during the coating process. Among them, the first temperature threshold can be 3 to 8°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 This is a flow chart of an optical fiber temperature control method according to an embodiment of the present application.

[0044] Figure 2 This is a flow chart of an optical fiber temperature control method according to an embodiment of the present application.

[0045] Figure 3 This is a schematic diagram of the structure of an optical fiber temperature control system according to an embodiment of the present application.

[0046] Figure 4 This is a diagram of optical fiber temperature changes in an optical fiber temperature control method according to an embodiment of the present application.

[0047] Figure 5 Schematic diagram of an optical fiber temperature control device according to an embodiment of the present application.

[0048] Description of Figure Numbers:

[0049] 100 optical fiber temperature control system; 10 optical fiber; 1 drawing device; 2 cooling device; 3 measuring device; 31 temperature measuring device; 311 cold pipe joint; 312 infrared temperature detection device; 4 coating device; 5 regulating device. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0051] During the fiber drawing process, the fiber is at a high temperature when it comes out of the drawing furnace and carries a lot of heat. At this time, before coating, the temperature of the fiber needs to be lowered to a range suitable for coating. Generally, the temperature is controlled in a specific range by a cooling device to ensure that the coating material can adhere normally. When the fiber temperature deviates greatly from the coating temperature, it will cause coating abnormalities, such as glue oozing, beads, thin lines, coating fluctuations and other quality problems, affecting the quality of the fiber.

[0052] First, as Figure 1 As shown, the present application provides a method for controlling the temperature of an optical fiber, comprising the following steps:

[0053] S100, obtaining the optical fiber temperature, the coating temperature and the optical fiber drawing rate;

[0054] S200. If the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to a first temperature threshold, adjust the cooling parameters according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold.

[0055] The present application obtains the fiber temperature, coating temperature and fiber drawing rate, and when the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, adjusts the cooling parameters according to the current fiber drawing rate, so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold, so that the absolute value of the difference between the fiber temperature and the coating temperature is controlled within the range less than the first temperature threshold, which can reduce the deviation between the fiber temperature and the coating temperature, improve temperature fluctuation, and reduce the quality problems such as glue bubbling, beading, thin wire, coating fluctuation, etc. during the coating process. Among them, the first temperature threshold can be 3 to 8 ° C. When - the first temperature threshold < T1-T2 < the first temperature threshold, the fiber temperature does not need to be adjusted; when T1-T2≤- the first temperature threshold, that is, the fiber temperature is lower than the coating temperature, the fiber temperature is increased so that the temperature difference meets the requirements. When T1-T2≥ the first temperature threshold, that is, the fiber temperature is higher than the coating temperature, the fiber temperature is reduced so that the temperature difference meets the requirements.

[0056] It should be noted that the cooling parameters that need to be controlled are different when the optical fiber drawing speed is different to achieve the same cooling temperature. This is because the faster the optical fiber drawing speed, the more heat it brings per unit time and the more cooling capacity is required. The slower the optical fiber drawing speed, the less heat it brings per unit time and the less cooling capacity is required. Therefore, by adjusting the cooling parameters according to the current optical fiber drawing speed, the optical fiber temperature can be accurately controlled and the deviation between the optical fiber temperature and the coating temperature can be reduced.

[0057] In combination with the first aspect, in some embodiments provided in the present application, the cooling parameters include at least one of the helium temperature, the helium flow rate, and the coolant temperature. Traditional cooling methods such as natural cooling or air cooling have extremely low cooling efficiency under high-speed wire drawing conditions and cannot meet the requirements for rapid cooling of optical fibers. Cold pipe cooling technology is mainly based on the principle of heat conduction and is usually made of materials with high thermal conductivity, such as copper and other metals. When the high-temperature optical fiber passes through the cold pipe, the optical fiber directly contacts the helium in the cold pipe for heat exchange, and the heat is transferred to the cold pipe. A coolant circulation system can be set inside the cold pipe or a special refrigeration structure can be used to maintain the low temperature state of the cold pipe, so that heat is continuously transferred from the optical fiber to the cold pipe and taken away. Therefore, the temperature of the optical fiber can be controlled by adjusting the helium temperature, the helium flow rate, and the coolant temperature.

[0058] In combination with the first aspect, in some embodiments provided in the present application, the optical fiber temperature is T1, the coating temperature is T2, the first temperature threshold is ΔT, and if T1-T2≥ΔT, it satisfies: the adjustment rate of the helium temperature = the first reference adjustment rate*(T1-T2), and the first reference adjustment rate is a coefficient related to the optical fiber drawing rate.

[0059] In combination with the first aspect, in some embodiments provided in the present application, the optical fiber temperature is T1, the coating temperature is T2, the first temperature threshold is ΔT, and if T1-T2≥ΔT, it satisfies: the adjustment rate of the helium flow rate = the second reference adjustment rate * (T1-T2), and the second reference adjustment rate is a coefficient related to the optical fiber drawing rate.

[0060] In combination with the first aspect, in some embodiments provided in the present application, the optical fiber temperature is T1, the coating temperature is T2, the first temperature threshold is ΔT, and if T1-T2≥ΔT, it satisfies: the adjustment rate of the cooling liquid temperature = the third reference adjustment rate*(T1-T2), and the third reference adjustment rate is a coefficient related to the optical fiber drawing rate.

[0061] By regulating the helium temperature, helium flow rate and coolant temperature according to the first reference regulating rate, the second reference regulating rate and the third reference regulating rate, which are coefficients related to the optical fiber drawing rate, the optical fiber temperature can be precisely controlled, and the absolute value of the difference between the optical fiber temperature and the coating temperature can be reduced. In particular, when the optical fiber drawing rate changes, the cooling parameters of the optical fiber can be precisely regulated based on the change in the optical fiber drawing rate, so as to achieve precise control of the optical fiber temperature.

[0062] In combination with the first aspect, in some embodiments provided in the present application, the first benchmark adjustment rate is 0.1-0.5°C / min. Within this range, the first benchmark adjustment rate can adapt to the control of optical fiber temperature under different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0063] In combination with the first aspect, in some embodiments provided in the present application, the second reference adjustment rate is 0.05 to 0.25 L / min. Within this range, the second reference adjustment rate can adapt to the control of optical fiber temperature under different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0064] In combination with the first aspect, in some embodiments provided in the present application, the third reference adjustment rate is 0.1-0.5°C / min. Within this range, the third reference adjustment rate can adapt to the control of optical fiber temperature under different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0065] In combination with the first aspect, in some embodiments provided in the present application, the adjustment range of the coolant temperature is -20°C to 20°C. Within this range, the adjustment range of the coolant temperature can adapt to the control of the optical fiber temperature at different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0066] In combination with the first aspect, in some embodiments provided in the present application, the adjustment range of the helium temperature is -20°C to 20°C. Within this range, the adjustment range of the helium temperature can adapt to the control of the optical fiber temperature under different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0067] In combination with the first aspect, in some embodiments provided in the present application, the adjustment range of the helium flow rate is 0 to 20 L / min. Within this range, the adjustment range of the helium flow rate can adapt to the control of the optical fiber temperature under different optical fiber drawing rates and reduce the absolute value of the difference between the optical fiber temperature and the coating temperature.

[0068] In combination with the first aspect, in some embodiments provided in the present application, such as Figure 2 As shown, if the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameter is adjusted according to the current optical fiber drawing rate so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold, then the cooling parameter is adjusted according to the current optical fiber drawing rate, including:

[0069] S201, establishing a correlation curve between different optical fiber drawing rates, different coolant temperatures, different helium temperatures, different helium flow rates and different optical fiber temperatures, and obtaining target coolant temperatures, target helium temperatures and target helium flow rates corresponding to different optical fiber temperatures at different optical fiber drawing rates;

[0070] S202: adjusting the current coolant temperature, the current helium temperature, and the current helium flow rate according to the target coolant temperature, the target helium temperature, and the target helium flow rate.

[0071] By introducing Fourier's law of heat conduction, Newton's law of cooling, convection heat dissipation, and Stefan-Boltzmann's law, a cooling simulation model can be established to obtain the relationship between the coolant temperature, helium temperature, helium flow process parameters and the fiber temperature at different fiber drawing speeds. The corresponding relationship between the coolant temperature, helium temperature, and helium flow parameters corresponding to different fiber temperatures at different drawing rates is established. The process parameters are pre-set through the corresponding relationship, and the fiber temperature can be controlled within a suitable range. The parameters are written into the PLC system and associated with the fiber drawing speed. The corresponding relationship can be obtained by pre-calibration, simulation calculation, or AI prediction. In actual production, by obtaining the fiber drawing speed and the current fiber temperature, the appropriate coolant temperature, helium temperature, and helium flow can be quickly selected for adjustment, and the fiber temperature can be quickly and accurately regulated, thereby reducing the deviation between the fiber temperature and the coating temperature.

[0072] In combination with the first aspect, in some embodiments provided in the present application, the optical fiber drawing rate is 1000m / min to 4000m / min. The optical fiber drawing rate within this range is a high-speed drawing process. In the high-speed drawing process, the optical fiber temperature and the coating temperature are more likely to have a large deviation. The optical fiber temperature control method at this drawing rate has a more significant effect on the optical fiber temperature control effect.

[0073] In a second aspect, the present application provides an optical fiber temperature control system 100, comprising:

[0074] A drawing device 1, used for drawing an optical fiber preform into an optical fiber 10;

[0075] A cooling device 2, provided at the outlet of the drawing device 1, for cooling the optical fiber 10;

[0076] Measuring device 3, used to measure the optical fiber temperature, coating temperature and optical fiber drawing rate;

[0077] A coating device 4, disposed at the outlet of the cooling device 2, for coating the surface of the optical fiber 10; and

[0078] The regulating device 5 is communicatively connected to the cooling device 2, and is used to adjust the cooling parameters according to the current drawing rate of the optical fiber 10 if the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold.

[0079] By obtaining the fiber temperature, coating temperature and fiber drawing rate, when the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameter is adjusted according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold, so that the absolute value of the difference between the fiber temperature and the coating temperature is controlled within a range less than the first temperature threshold, which can reduce the deviation between the fiber temperature and the coating temperature, improve temperature fluctuation, and reduce the quality problems such as glue oozing, beading, thin lines, coating fluctuations, etc. during the coating process. Among them, the first temperature threshold can be 3 to 8°C.

[0080] By improving the quality problem caused by the large deviation between the fiber temperature and the coating temperature after the fiber is cooled during the high-speed drawing process, and optimizing the cooling system, an optical fiber cooling control system 100 is established, and the optical fiber temperature control is achieved through PLC adjustment to control the mismatch between the fiber temperature and the coating temperature during the high-speed drawing process.

[0081] Combined with the second aspect, such as Figure 3 As shown, in some embodiments provided in the present application, the measuring device 3 includes a temperature measuring device 31, and the temperature measuring device 31 includes a cold pipe joint 311 and an infrared temperature detection device 312. The cold pipe joint is used to connect the cooling pipe of the cooling device and the coating device 4. The cold pipe joint is provided with a circular hole, and the infrared temperature detection device measures the temperature of the optical fiber through the circular hole.

[0082] The temperature of the optical fiber 10 is measured through the cold pipe joint 311 and the round hole on the cold pipe joint, thereby improving the accuracy of temperature control of the optical fiber 10. The coating temperature and the optical fiber 10 temperature signal can be connected to the system through the PLC.

[0083] The cooling device 2 can be a hollow metal tube with an interlayer, in which circulating cooling water is injected. The temperature of the cooling tube is adjusted by a water bath, and the temperature signal is connected to the system by a PLC. The cooling gas helium is introduced from the bottom of the cooling tube. The temperature and flow of the cooling gas can be adjusted by a temperature control device and a flow meter, and the temperature and flow signals are connected to the system through a PLC.

[0084] Thirdly, Figure 4 As shown, the present application provides an optical fiber temperature control device, comprising:

[0085] An acquisition unit, used to acquire the optical fiber temperature, the coating temperature and the optical fiber drawing rate;

[0086] A control unit is used to adjust the cooling parameters according to the current optical fiber drawing rate if the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold.

[0087] By obtaining the fiber temperature, coating temperature and fiber drawing rate, when the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameter is adjusted according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold, so that the absolute value of the difference between the fiber temperature and the coating temperature is controlled within a range less than the first temperature threshold, which can reduce the deviation between the fiber temperature and the coating temperature, improve temperature fluctuation, and reduce the quality problems such as glue oozing, beading, thin lines, coating fluctuations, etc. during the coating process. Among them, the first temperature threshold can be 3 to 8°C.

[0088] The technical solution provided in this application is described in detail below in conjunction with embodiments.

[0089] Example 1

[0090] An optical fiber temperature control method comprises the following steps:

[0091] The optical fiber preform is heated to above the softening point, so that it is drawn into 125μm optical fiber filaments under tension. The optical fiber drawing speed is 3500m / min, and the temperature out of the high-temperature furnace is about 800℃;

[0092] The optical fiber is cooled by a cold tube, which is a hollow metal tube with an inner diameter of 10 mm and an outer diameter of 50 mm and a sandwich. Circulating cooling water is injected into the sandwich from bottom to top, and cooling helium is introduced from the bottom of the cold tube. The temperature of the cooling tube, the temperature of the helium, and the flow rate of the helium are automatically adjusted by the PLC access system.

[0093] By introducing Fourier's law of heat conduction, Newton's law of cooling, convection heat dissipation, and Stefan-Boltzmann's law, a fiber cooling model is established and simulated. The relationship between the cooling tube temperature, helium temperature, and helium flow process parameters and the fiber temperature at different speeds can be obtained, as shown in Table 1:

[0094] Table 1 Cooling conditions at different drawing rates

[0095]

[0096] The fiber drawing speed is 3500m / min, the corresponding coating temperature T2 is 65℃, the preset cooling process parameters are cooling tube temperature 10℃, helium temperature 10℃, and flow rate 8L / min; under this cooling parameter, the fiber temperature changes as follows Figure 5 As shown;

[0097] The infrared temperature detection device detects that the fiber temperature T1 is 72°C and the coating temperature T2 is 65°C through the cold pipe joint with a round hole. The fiber temperature is too high and parameters need to be adjusted. The PLC adjusts the cooling process. The cooling pipe temperature, helium temperature, and helium temperature reference adjustment coefficient are -0.2°C / min, -0.2°C / min, and 0.1L / min. The temperature coefficient is multiplied by 7 during adjustment. At this time, the cooling pipe temperature, helium temperature, and helium flow adjustment coefficient are -1.4°C / min, -1.4°C / min, and 0.7L / min. Adjust until the fiber temperature is 70°C. At this time, the cooling parameters are no longer adjusted, and the fiber temperature and coating temperature are continuously monitored to achieve fiber temperature control.

[0098] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0099] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0100] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0101] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0102] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0103] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for controlling optical fiber temperature, characterized in that: The following steps are involved: Obtain the fiber temperature, coating temperature and fiber drawing rate; If the absolute value of the difference between the fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameters are adjusted according to the current fiber drawing rate so that the absolute value of the difference between the fiber temperature and the coating temperature is less than the first temperature threshold.

2. The optical fiber temperature control method according to claim 1, characterized in that: The cooling parameter includes at least one of helium temperature, helium flow rate and coolant temperature.

3. The optical fiber temperature control method according to claim 2, characterized in that: The fiber temperature is T1, the coating temperature is T2, and the first temperature threshold is ΔT. If T1-T2≥ΔT, then: Helium temperature regulation rate = first reference regulation rate * (T1-T2); and / or, Helium flow rate adjustment rate = second reference adjustment rate * (T1-T2); and / or, Coolant temperature adjustment rate = third reference adjustment rate * (T1-T2); Among them, the first reference adjustment rate, the second reference adjustment rate and the third reference adjustment rate are coefficients related to the optical fiber drawing rate.

4. The optical fiber temperature control method according to claim 3, characterized in that: The first reference adjustment rate is 0.1-0.5°C / min; and / or, The second reference adjustment rate is 0.05-0.25 L / min; and / or, The third reference adjustment rate is 0.1-0.5°C / min.

5. The optical fiber temperature control method according to claim 2, characterized in that: The adjustment range of the coolant temperature is -20°C to 20°C; and / or, The helium temperature is adjusted in the range of -20°C to 20°C; and / or, The adjustment range of helium flow rate is 0~20L / min.

6. The optical fiber temperature control method according to claim 2, characterized in that: If the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, the cooling parameter is adjusted according to the current optical fiber drawing rate so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold, and the cooling parameter is adjusted according to the current optical fiber drawing rate. Establish correlation curves among different optical fiber drawing rates, different coolant temperatures, different helium temperatures, different helium flow rates and different optical fiber temperatures, and obtain target coolant temperatures, target helium temperatures and target helium flow rates corresponding to different optical fiber temperatures at different optical fiber drawing rates; According to the target coolant temperature, the target helium temperature and the target helium flow rate, the current coolant temperature, the current helium temperature and the current helium flow rate are adjusted.

7. The optical fiber temperature control method according to claim 1, characterized in that: The drawing rate of the optical fiber is 1000m / min to 4000m / min.

8. An optical fiber temperature control system, characterized in that: include: A drawing device, used for drawing the optical fiber preform into an optical fiber; A cooling device, provided at the outlet of the drawing device, for cooling the optical fiber; A measuring device for measuring the optical fiber temperature, the coating temperature and the optical fiber drawing rate; A coating device, disposed at the outlet of the cooling device, for coating the surface of the optical fiber; and The regulating device is communicatively connected to the cooling device, and is used to adjust the cooling parameters according to the current drawing rate of the optical fiber if the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold.

9. The optical fiber temperature control system according to claim 8, characterized in that: The measuring device includes a temperature measuring device, which includes a cold pipe joint and an infrared temperature detection device. The cold pipe joint is used to connect the cooling pipe of the cooling device and the coating device. The cold pipe joint is provided with a circular hole, and the infrared temperature detection device measures the optical fiber temperature and the coating temperature through the circular hole.

10. An optical fiber temperature control device, characterized in that: include: An acquisition unit, used to acquire the optical fiber temperature, the coating temperature and the optical fiber drawing rate; A control unit is used to adjust the cooling parameters according to the current optical fiber drawing rate if the absolute value of the difference between the optical fiber temperature and the coating temperature is greater than or equal to the first temperature threshold, so that the absolute value of the difference between the optical fiber temperature and the coating temperature is less than the first temperature threshold.

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