Guide to the operating principle of the two-color fixed thermometer
Guidance on the operating principle of the two-color fixed thermometer: The two-color infrared thermometer is a kind of infrared thermometer. It can also be called a fiber optic two-color infrared thermometer, which measures the infrared radiance emitted by an object in two different spectral ranges and infers the temperature of the object from the ratio of the two radiant luminances. It is called a two-color thermometer. In fact, the two-color thermometer does not have the meaning of brightness and color. Compared with the brightness thermometer (optical pyrometer), the two are different in principle. The meaning of "color" here should be infrared wavelength or spectrum, that is, "double infrared spectrum thermometer"
The two-color online thermometer is an effective tool for detecting and diagnosing electronic equipment failures. There are many varieties of fixed infrared thermometers, and different series play an important role in their respective applicable industries. The main performance indicators of fixed infrared thermometers are spectral response, response time, repeatability and emissivity. Fixed infrared thermometers are used in glass and ceramic industries, papermaking and packaging industries, various kiln temperature measurement applications, and chemical industry to measure the temperature of instruments and meters, so as to detect the operating status of instruments and meters and ensure the normal operation of an instrument. run.
Guidance on the operating principle of the two-color fixed thermometer:
The two-color infrared thermometer is composed of an optical system, a color separation film or a filter, an infrared detector, a signal processor and a display output part. The two-color thermometer measures the luminance emitted by the object in two different spectral ranges, and converts the ratio of the two radiances into the temperature of the object. Therefore, it is fundamentally different from the monochrome thermometer in principle. The key to the instrument lies in the selection of the two bands. The selection principle is: the signal ratio of the two bands is sensitive to temperature changes. When the temperature has a small change, the ratio of the signals in the two bands is still large, which will make the instrument have a larger temperature resolution.
Advantages of online temperature measurement Infrared thermometers in the steel industry
The steel industry uses thermometers because the products are in motion and the temperature is very high. A common steel industry application is that the temperature is a constant state where molten steel begins to transform into lumps. Reheating the steel to the same temperature is key to preventing it from warping, and infrared thermometers are used to measure the internal temperature of the regenerator. In high temperature rotary mills, infrared thermometers are used to confirm that the temperature of the product is within rotation limits. In cooling mills, infrared thermometers monitor the temperature of the steel as it cools.
Guidance on the operating principle of the two-color fixed thermometer: Infrared thermometers are used in the glass industry to be heated to very high temperatures. Infrared thermometers are used to monitor the temperature in the furnace. Hand-held sensors detect hot spots by measuring outside. Measure the temperature of the molten glass to determine the proper furnace mouth temperature. In flat glass products, sensors detect the temperature at every processing stage. Wrong temperature or too rapid temperature change can cause uneven expansion or contraction. For bottle and container products, the molten glass flows to a forehearth maintained at the same temperature. Infrared thermometers are used to detect the temperature of the glass in the forehearth. So it should be in the proper state where it is exported. In fiberglass products, infrared sensors are used in the processing furnace to detect the temperature of the glass in the forehearth. Another use of infrared sensors in the glass industry is in the process of windshield products.
Application of two-color infrared thermometer in plastic industry:
In the plastics industry, infrared thermometers are used to avoid product contamination, measure dynamic objects and measure high temperature plastics. Temperature measurements to adjust for heating and cooling during blown film extrusion can help maintain the integrity of the plastic's tension and its thickness. During ejection of cast film, sensors help control temperature to ensure product thickness and consistency. During sheet extrusion, sensors allow the operator to adjust the heaters and cold coils to be turned off to maintain product quality.
Infrared thermometer chemical industry applications:
In the petrochemical industry, refineries employ temperature display systems as part of routine preventive maintenance programs. These procedures include monitoring of the furnace process and verification of thermocouple readings. In the detection of furnace process, infrared display is used to detect the proportion of carbon accumulation in the heating surface tube. This buildup, known as coking, results in a higher firing rate of the furnace, which also increases the temperature of the tubes. This high temperature condition will reduce the life of the tube. Because this coking will prevent the product from absorbing the heat of the pipe evenly. When using an infrared thermometer, we will find that the surface temperature of the tube in the junction area tends to be higher than that in other areas.
The operating principle guidance of the two-color fixed thermometer can also play a role in preventive maintenance:
With a portable thermal display system, maintenance personnel can identify potential or existing problems. Examples: Overheated engine coil windings, plugged cooling fins on transformers, capacitor contacts, heat buildup in compressor cylinder head. Any problem is accompanied by a temperature rise, or a temperature curve that is sharply different from the surrounding temperature, so that it can be located with a portable thermal display system. In most cases, the problem can be found in time and corrected in time before the process is required to be stopped.
Comparative analysis of online infrared thermometer and handheld:
Online infrared thermometers are mostly used for online temperature measurement at industrial production sites. They measure and transmit/display the temperature of a certain part of the production line in real time in the control room, and even directly participate in closed-loop control. Such a thermometer generally requires long-term stability and reliability.
The handheld infrared thermometer is a kind of portable infrared thermometer, which is a small and portable infrared thermometer.
The difference between online and hand-held infrared thermometers lies in the use environment and temperature measurement accuracy. Hand-held infrared thermometers can be used in indoor and outdoor working environments because they are easy to carry, and are basically not limited by the environmental site, but relatively Compared with the online infrared thermometer, its temperature measurement accuracy is slightly worse. The online infrared thermometer is larger than the handheld, and it is not easy to move. It is limited by the use of the site, but its temperature measurement accuracy is high, and it can also be measured online. Temperature comparison and analysis are not available in handheld thermometers. Of course, the price of online thermometers is also higher than that of handheld thermometers. In terms of industry, the accuracy of online thermometers is much higher.
