Distributed temperature sensing optical cable structure of integrated cold box
By integrating a cold box structure and a constant temperature device, the problems of large measurement deviations and easy damage to connectors in traditional optical cables in complex environments are solved, achieving high-precision temperature monitoring and low-cost maintenance, and making it suitable for various environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WUHAN TUOXIN OPTOELECTRONICS CO LTD
- Filing Date
- 2025-05-14
- Publication Date
- 2026-05-19
AI Technical Summary
Traditional distributed temperature sensing optical cables exhibit large measurement deviations in complex environments, are prone to damage to optical connectors, and are difficult to maintain, thus affecting measurement accuracy and system reliability.
It adopts an integrated cold box structure with an internal constant temperature device and waterproof and dustproof design, including a temperature sensor, a semiconductor cooling chip and a heating resistance plate. The constant temperature environment of 20℃±0.5℃ is maintained by a PID controller. The bare optical fiber is coiled inside the cold box, and the outer shell is made of polyurethane foam insulation material.
It improves the accuracy of temperature measurement and the reliability of the system, reduces maintenance costs and difficulty, adapts to harsh environments, and meets diverse temperature monitoring needs.
Smart Images
Figure CN224262659U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of optical cable technology, and in particular to a distributed temperature sensing optical cable structure with an integrated cold box. Background Technology
[0002] With the widespread application of distributed temperature sensing technology, accurate temperature monitoring is crucial for many fields, including power systems, petrochemicals, transportation, and building structural health monitoring.
[0003] In existing technologies, traditional distributed temperature sensing optical cables cannot effectively control the ambient temperature of the optical fiber in terms of temperature measurement. Due to the temperature sensitivity of optical fiber optical characteristics, temperature fluctuations in complex environments such as power cable trenches and long-distance oil and gas pipelines lead to large deviations in measurement results, making it difficult to meet the requirements of high-precision monitoring. In terms of optical connectors, the connectors made at both ends are fragile and easily damaged by external pulling forces and environmental corrosion. Repair requires professional personnel and precision equipment, and operation is difficult and quality cannot be guaranteed in special working environments. It also introduces new optical losses, affecting the quality of optical signal transmission, leading to a decrease in measurement accuracy or even interruption of the monitoring system, which seriously affects the real-time monitoring of critical areas. Therefore, it is necessary to propose a distributed temperature sensing optical cable structure with an integrated cold box to address the above problems. Utility Model Content
[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a distributed temperature sensing optical cable structure with an integrated cold box.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A distributed temperature sensing optical cable structure with an integrated cold box includes a temperature sensing optical cable. Both ends of the temperature sensing optical cable are connected to bare optical fibers of the same type, with a length of 20-30 meters. Cold boxes are located at both ends of the temperature sensing optical cable. The cold boxes encapsulate the splice points of the bare optical fibers. The remaining bare optical fibers are loosely coiled in a coiled area inside the cold boxes, with one end leading out from the outlet of the cold boxes. A temperature control device is provided inside the cold boxes. The temperature control device includes a temperature sensor, a thermoelectric cooler, and a heating resistor plate. The thermoelectric cooler and heating resistor plate are respectively located on the left and right sides of the bare optical fibers. A PID controller is electrically connected to the temperature sensor, thermoelectric cooler, and heating resistor plate. A thermally conductive aluminum plate covers the inner wall of the cold boxes and contacts the thermoelectric cooler and heating resistor plate. A temperature display screen is provided on the surface of the cold boxes. FC / APC optical connectors are fabricated at both ends of the bare optical fibers. The FC / APC optical connectors are used to connect to a distributed temperature measurement system (DTS).
[0007] Preferably, the optical fiber inlet of the cold box is located on the left side and the outlet is located on the right side, and the bare optical fiber is coiled clockwise from the inlet to the outlet.
[0008] Preferably, the set temperature of the PID controller is 20℃±0.5℃, and the temperature recovery stabilization time does not exceed 60 seconds.
[0009] Preferably, the outer shell of the cold box is made of polyurethane foam insulation material and has a waterproof and dustproof sealing structure on the outside.
[0010] Preferably, the length of the bare optical fiber reserved in the coiled area is 20 to 30 meters.
[0011] Preferably, the thermally conductive aluminum plate is in close contact with the cold side of the semiconductor refrigeration chip and the heating side of the heating resistance plate.
[0012] This utility model has the following beneficial effects:
[0013] 1. This utility model, through a constant temperature device inside the cold box, can precisely control the temperature inside the cold box at 20℃±0.5℃, creating a stable temperature environment for the bare optical fiber. This greatly reduces the interference of ambient temperature fluctuations on measurement accuracy. Precise temperature control makes temperature calibration more reliable, ensuring the accuracy and stability of temperature measurement results. It provides accurate data support for temperature monitoring of important facilities such as power cables and oil and gas pipelines, effectively avoiding safety accidents caused by inaccurate temperature monitoring and improving the reliability and safety of related systems.
[0014] 2. This utility model, by reserving 20-30 meters of bare optical fiber inside the cold box, eliminates the need to replace the entire optical cable when the FC / APC optical connector is damaged, reducing maintenance costs and difficulty and improving system maintainability. At the same time, the cold box adopts polyurethane foam insulation material and a waterproof and dustproof sealing structure, giving it good environmental adaptability and enabling it to work stably in harsh environments. This expands the application scenarios of distributed temperature sensing optical cables, allowing them to operate reliably in high-temperature and high-humidity outdoor environments as well as industrial areas with heavy dust, meeting the diverse needs of different fields for temperature monitoring. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of a distributed temperature sensing optical cable structure with an integrated cold box proposed in this utility model.
[0016] Figure 2 for Figure 1 Structural diagram.
[0017] Figure 3 This is a block diagram of the internal structure of the cold box in section 1.
[0018] In the diagram: 1. Temperature-sensing optical cable; 2. Bare optical fiber; 3. Cold box; 4. FC / APC optical connector; 5. Temperature display screen. Detailed Implementation
[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.
[0020] Reference Figure 1-3 A distributed temperature sensing optical cable structure with an integrated cold box includes a temperature sensing optical cable 1, with bare optical fibers 2 of the same type connected to both ends of the temperature sensing optical cable 1. The length of the bare optical fibers 2 is 20-30 meters. Cold boxes 3 are set at both ends of the temperature sensing optical cable 1. The fusion splice of the bare optical fibers 2 is encapsulated inside the cold box 3. The remaining bare optical fibers 2 are loosely coiled in a coiled area inside the cold box 3, and one end of the bare optical fibers 2 is led out from the outlet of the cold box 3. A constant temperature device is set inside the cold box 3. The constant temperature device includes: a temperature sensor, a semiconductor cooling chip and a heating resistance plate. The semiconductor cooling chip and the heating resistance plate are respectively set on the left and right sides of the bare optical fibers 2. A PID controller is electrically connected to the temperature sensor, the semiconductor cooling chip and the heating resistance plate. A heat-conducting aluminum plate covers the inner wall of the cold box 3 and is in contact with the semiconductor cooling chip and the heating resistance plate. A temperature display screen 5 is set on the surface of the cold box 3. FC / APC optical connectors 4 are made at both ends of the bare optical fibers 2. The FC / APC optical connectors 4 are used to connect to a distributed temperature measurement system (DTS).
[0021] Furthermore, by setting cold boxes 3 at both ends of the temperature-sensing optical cable 1 and encapsulating the splice points, the fragile optical fiber connection parts can be effectively protected, preventing them from being directly exposed to complex environments and reducing the risk of damage caused by external forces or environmental erosion. By placing the semiconductor cooling chip and heating resistance plate on opposite sides of the bare optical fiber 2 and uniformly conducting temperature through a heat-conducting aluminum plate, the bare optical fiber 2 can be kept in a stable constant temperature environment, reducing the impact of ambient temperature fluctuations on measurement accuracy and solving the problem of large temperature measurement deviations in traditional technologies. The temperature display screen 5 facilitates real-time monitoring of the temperature status inside the cold box 3, providing maintenance personnel with intuitive temperature data and helping to promptly detect potential anomalies.
[0022] The optical fiber inlet of the cold box 3 is located on the left and the outlet is located on the right. The bare optical fiber 2 is coiled clockwise from the inlet to the outlet.
[0023] Furthermore, the coiling method of the bare optical fiber 2 optimizes the fiber's orientation within the cold box 3, reducing fiber bending loss and ensuring the quality of optical signal transmission. The clockwise coiling method also facilitates a more uniform temperature field distribution, resulting in more even heating or cooling of different parts of the bare optical fiber 2, further improving the accuracy and consistency of temperature measurements, making it suitable for long-distance distributed temperature monitoring scenarios.
[0024] The PID controller is set to a temperature of 20℃±0.5℃, and the temperature recovery time should not exceed 60 seconds.
[0025] Furthermore, the PID controller is set to a precise constant temperature range of 20℃±0.5℃, providing stable conditions for the optical fiber close to the standard ambient temperature. This eliminates the drift of optical fiber characteristics caused by changes in ambient temperature, improving the accuracy of temperature calibration and the reliability of measurement results.
[0026] The outer shell of the cold box 3 is made of polyurethane foam insulation material and has a waterproof and dustproof sealing structure on the outside;
[0027] Furthermore, the outer shell of the cold box 3 is made of polyurethane foam insulation material, which can effectively isolate external temperature interference, reduce heat transfer, reduce the energy consumption of the constant temperature device, and enhance the stability of the internal temperature of the cold box 3.
[0028] The bare optical fiber 2 in the coiled area has a reserved length of 20-30 meters;
[0029] Furthermore, a length of 20-30 meters of bare optical fiber is reserved in the coiling area, providing ample operational margin for the installation, maintenance, and repair of the optical cable.
[0030] The thermally conductive aluminum plate is in close contact with the cold side of the semiconductor refrigeration chip and the heating side of the heating resistance plate;
[0031] Furthermore, the close contact between the heat-conducting aluminum plate and the cold side of the semiconductor refrigeration chip and the heating resistance plate enables efficient heat conduction, allowing the cooling or heating effect to be applied quickly and evenly to the internal space of the cold box 3.
[0032] In this invention, the device is used as follows: For temperature monitoring, the temperature-sensing optical cable 1 is connected to a distributed temperature measurement system (DTS) via bare optical fibers 2 of the same type at both ends. The temperature control device inside the cold box 3 uses a temperature sensor to monitor the internal temperature of the cold box 3 in real time. When the temperature is higher than the set value by 20℃±0.5℃, the PID controller receives the signal from the temperature sensor and controls the thermoelectric cooler to start cooling. The thermoelectric cooler operates based on the Peltier effect, absorbing heat on the cold side and dissipating heat on the hot side. When the temperature is lower than the set value, the PID controller controls the heating resistance plate to heat up. A heat-conducting aluminum plate covers the inner wall of the cold box 3 and is in close contact with the thermoelectric cooler and the heating resistance plate, enabling rapid and uniform heat conduction, creating a stable and uniform temperature field inside the cold box 3, and keeping the bare optical fiber 2 in a constant temperature environment. This overcomes the problem of environmental temperature fluctuations affecting measurement accuracy in traditional technologies, providing a stable and reliable reference for temperature calibration and ensuring the accuracy of temperature measurements. Meanwhile, the temperature display screen 5 on the surface of the cold box 3 displays the internal temperature in real time, which makes it convenient for maintenance personnel to intuitively grasp the temperature status inside the cold box 3, so as to promptly detect and deal with abnormalities.
[0033] Regarding the fiber optic routing and temperature field distribution, the fiber optic inlet of the cold box 3 is located on the left, and the outlet is located on the right. The bare fiber 2 is coiled clockwise from the inlet to the outlet. This coiling method optimizes the fiber optic routing within the cold box 3, reduces the loss of optical signal transmission due to fiber bending, and ensures stable optical signal transmission. Moreover, the clockwise coiling helps to distribute the temperature field evenly within the cold box 3, making the heating or cooling of different parts of the bare fiber 2 more uniform, further improving the accuracy and consistency of temperature measurement. This is suitable for long-distance distributed temperature monitoring scenarios, as long-distance monitoring has higher requirements for the consistency of temperature measurement.
[0034] From the perspective of equipment stability and ease of maintenance, the outer shell of the cold box 3 is made of polyurethane foam insulation material and has a waterproof and dustproof sealing structure. The polyurethane foam insulation material effectively blocks the influence of external temperature on the interior of the cold box 3, reduces heat transfer, lowers the energy consumption of the temperature control device, and enhances the stability of the internal temperature of the cold box 3, ensuring the normal operation of the temperature control device. The waterproof and dustproof sealing structure prevents sand, dust, and moisture from entering the interior of the cold box 3, avoiding damage to the optical fiber and internal electronic components, and extending the service life of the equipment. In addition, 20-30 meters of bare optical fiber 2 is reserved in the coiling area, providing ample operational margin for the optical cable during installation, maintenance, and repair. When the FC / APC optical connector 4 is damaged, it is not necessary to replace the entire optical cable; a certain length of bare optical fiber 2 can be directly pulled from the cold box 3 to remake the connector or direct-fusion patch cord, greatly reducing maintenance costs and difficulty and improving the maintainability of the system.
[0035] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. A distributed temperature sensing optical cable structure with an integrated cold box, comprising a temperature sensing optical cable (1), characterized in that, The temperature-sensing optical cable (1) has bare optical fibers (2) of the same type connected to its front and rear ends respectively. The length of the bare optical fibers (2) is 20-30 meters. Cold boxes (3) are provided at both ends of the temperature-sensing optical cable (1). The fusion splice of the bare optical fibers (2) is encapsulated in the cold box (3). The remaining bare optical fibers are loosely coiled in a coiled area inside the cold box (3), and one end of the bare optical fibers (2) is led out from the outlet of the cold box (3). A constant temperature device is provided inside the cold box (3). The constant temperature device includes: a temperature sensor, a semiconductor cooling chip, and a thermoelectric cooler. A heating resistance plate is provided on the left and right sides of the bare optical fiber (2), the semiconductor cooling chip and the heating resistance plate are respectively disposed on the left and right sides of the bare optical fiber (2), the PID controller is electrically connected to the temperature sensor, the semiconductor cooling chip and the heating resistance plate, the thermally conductive aluminum plate covers the inner wall of the cold box (3) and contacts the semiconductor cooling chip and the heating resistance plate, the surface of the cold box (3) is provided with a temperature display screen (5), and FC / APC optical connectors (4) are respectively made at both ends of the bare optical fiber (2), the FC / APC optical connectors (4) are used to connect the distributed temperature measurement system (DTS).
2. The distributed temperature sensing optical cable structure with an integrated cold box according to claim 1, characterized in that, The optical fiber inlet of the cold box (3) is located on the left side and the outlet is located on the right side. The bare optical fiber (2) is coiled clockwise from the inlet to the outlet.
3. The distributed temperature sensing optical cable structure with an integrated cold box according to claim 2, characterized in that, The PID controller is set to a temperature of 20℃±0.5℃, and the temperature recovery time is no more than 60 seconds.
4. The distributed temperature sensing optical cable structure with an integrated cold box according to claim 3, characterized in that, The outer shell of the cold box (3) is made of polyurethane foam insulation material and has a waterproof and dustproof sealing structure on the outside.
5. The distributed temperature sensing optical cable structure with an integrated cold box according to claim 4, characterized in that, The bare optical fiber (2) in the coiled area has a reserved length of 20 to 30 meters.
6. The distributed temperature sensing optical cable structure with an integrated cold box according to claim 5, characterized in that, The thermally conductive aluminum plate is in close contact with the cold side of the semiconductor refrigeration chip and the heating side of the heating resistance plate.