Optical fiber thermometer, also known as optical fiber sensing thermometer, belongs to infrared thermometer. The principle is to sense the infrared rays emitted by the object itself in a non-contact way, and detect the surface temperature of the object. In a common infrared thermometer, the main principle is to sense the infrared rays emitted by the object itself in a non-contact manner to detect the surface temperature of the object. In the case of a separate optical fiber infrared temperature measuring instrument, the difference from the usual infrared temperature measuring instrument is that the optical path system and the electric circuit system of the temperature measuring instrument can be separated by transmitting infrared rays to the sensor via an optical fiber. Then, as follows Let's learn about the advantages of fiber optic thermometers in metallurgical process temperature measurement!

The advantages of optical fiber thermometer in metallurgical process

1. The optical path system is separated from the electrical circuit system. In the industrial site, high temperature or special environment, the optical path system of the thermometer can be set in a high temperature environment (it can withstand a field environment of 250 degrees), and it can work stably online for a long time.
2. The infrared signal of the optical fiber infrared thermometer is transmitted to the sensor through a special infrared optical fiber material, so while the optical path is focused on the optical fiber, the light spot can be transmitted to the sensor through the optical fiber, and the large area of light is directly focused on the sensor, which will not affect the sensor. Sensor causes aging
3. Not disturbed by atmospheric dust, smoke, steam and particles;
4. Perspective windows, transparent glass, etc.;
5. The visual field (optical path) of the instrument is partially blocked or blocked, which will not be affected;
6. The target does not meet the field of view (the measured target is smaller than the measurement point);
7. Suitable for moving or vibrating objects.

The optical fiber thermometer system is composed of optical fiber thermometer, temperature-sensing optical cable, measurement software and other supporting equipment. It is a time-domain distributed temperature monitoring system. The principle is the technical basis, and the optical domain reflection technology is adopted (the measurement range can reach tens of kilometers, and the spatial positioning accuracy can reach 1m. It has been widely used in electric power, petrochemical, coal, tunnel, fire protection and other industries.

After the optical fiber thermometer enters the sensing fiber, the propagation of photons in the fiber is affected by the density, stress, doping in the fiber, temperature, bending deformation, etc., so some scattered light reflects along the incident light. Propagating in the forward direction is called backscattered light.

The optical fiber thermometer detects light entering the optical fiber, and generates spontaneous Raman scattering during the transmission process, and the generated post-Stokes light is temperature-sensitive, that is, it increases with the increase of temperature. Combined with optical domain reflectance technology for spatial positioning and analysis of the compared Raman scattering signals, the temperature information corresponding to any point along the fiber can be obtained. Real-time distributed monitoring of object temperature information.