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Six typical applications of fiber optic temperature measurement technology http://yunrun.com.cn/tech/2515.html Fiber optic temperature measurement technology is a new technique that has developed in recent years, and it has gradually shown certain excellent properties. However, just like other new technologies, fiber optic temperature measurement is not a panacea; it is not meant to replace traditional methods, but rather to complement and improve them. By fully leveraging its strengths, new temperature measurement methods and technologies can be developed. The applications of fiber optic temperature measurement technology are as follows. 1. Temperature measurement in strong electromagnetic fields: High-frequency and microwave heating methods have attracted considerable attention, and are gradually being applied in areas such as high-frequency melting, welding, and quenching of metals; vulcanization of rubber; drying of wood and fabrics; as well as in the pharmaceutical and chemical industries, and even in home cooking. Fiber optic temperature measurement technology has a clear advantage in these fields, as it suffers neither from additional heating caused by conductive parts nor from interference from electromagnetic fields. 2. Temperature measurement of high-voltage electrical equipment: The most typical application of fiber optic temperature sensors is the measurement of the temperature at hot spots in the windings of high-voltage transformers. The UK Electric Power Research Centre has been devoted to research on this topic since the mid-1970s; initially for fault diagnosis and prediction, and later for applications in computerized electric power management, leading to safe overloading operations that ensure the system is in an optimal power distribution state. Another category of applications is various high-voltage devices, such as generators, high-voltage switches, overload protection devices, and even overhead power lines and underground cables. 3. Temperature measurement in the production process of flammable and explosive materials and related equipment: Fiber optic temperature sensors are, by nature, fire and explosion-proof devices; they do not require any explosion-proof measures, making them very safe and reliable. Compared to electrical sensors, it can reduce costs while improving sensitivity. For example, the reaction tanks in large-scale chemical plants operate under high temperature and pressure conditions. Real-time monitoring of the surface temperature characteristics of these tanks ensures their proper operation. By laying optical fibers along the tank’s surface to form a temperature sensing network, any hot spots can be detected, thereby enabling effective prevention of accidents. 4. Temperature measurement of high-temperature media: In the metallurgical industry, there are many challenges related to temperature measurement when the temperature is above 1300°C or 1700°C, or when the temperature is not that high but the operating conditions are harsh. By fully leveraging the advantages of fiber-optic temperature sensing technology, some of these challenges are expected to be resolved. For example, issues such as the continuous temperature measurement of molten steel, molten iron, and related equipment, as well as the temperature distribution within blast furnace shells, are areas of research that are being carried out both domestically and internationally. 5. Bridge safety inspection: In domestic projects related to the safety inspection of large bridges, fiber bragg grating sensors are used to monitor the stress, strain, and temperature changes of these bridges under various conditions. Eight fiber bragg grating strain sensors and four fiber bragg grating temperature sensors were installed on the selected end faces of the bridge. The 8 strain sensors were connected in series to form one channel, and the 4 temperature sensors were also connected in series to form one channel; these signals were then transmitted via optical fibers to the bridge control room, enabling centralized management of the bridge. Based on the test results, the data obtained by the fiber Bragg grating sensor are consistent with the expected results. 6. Molten steel casting inspection: During casting, in order to prevent oxidation of the molten steel and improve its quality, it is necessary for the molten steel to flow from the ladle to the tundish in a state of complete isolation from air. But in reality, once the large-scale casting is complete, the operator visually checks whether slag has flowed out; therefore, the airtight condition is broken 5–10 minutes before the end of the large-scale casting. To prevent deterioration in the quality of the cast billets and incorrect judgments regarding slag leakage, an optical fiber slag leakage detection device has been developed. The application of fiber optic temperature measurement technology is not limited to the areas mentioned above. Compared with traditional thermocouple-based temperature measurement methods, it has a wide range of applications in fields such as microelectronics, medical diagnosis, and research on smart materials; Changhui Instruments will not go into further detail on this here.