Ladle is an important accepting and transferring device of molten steel in steelmaking production. The baking process of ladle after laying is very important to ladle life and steelmaking production.  In order to control the roasting system and fuel consumption, it is necessary to accurately monitor the roasting temperature of ladle lining refractory in order to make different baking temperature curves and time nodes according to the characteristics of ladle refractory.  

    Thermocouple temperature measurement is the most commonly used temperature measurement method, but also one of the more classical methods.  The basic principle is that according to the Seebeck effect, two conductors or semiconductors of different materials are connected together at different temperatures, and the circuit will generate a thermoelectric potential, which in turn generates a thermal current.  In this way, the temperature signal is converted to the current signal, and the size of the current signal can be measured to get the size of the temperature.  

    The concrete realization method is that the movable furnace cover on the top of the ladle is provided with a baking device and a temperature measuring thermocouple, and the temperature of the furnace cover is replaced by the baking temperature of the ladle resistant material.  This method has the advantages of simple structure and reliable measurement, but its main disadvantage is that it is difficult to measure high temperature due to material limitation.  

    But in practice, the temperature of the lid cannot reflect the baking temperature of the inner wall of ladle accurately because of the influence of the length of the flame and the emission of flue gas.  At the same time, the ladle is closed during baking, so it is difficult to measure the temperature of inner wall indirectly.  Therefore, it is necessary to develop a technique and method to accurately measure ladle baking temperature.  

    The optical fiber pyrometer is installed on the ladle cover, and the temperature of the object can be calculated according to the wavelength or frequency of the heat radiation in the ladle.  The company has already applied this technology maturely and got good application effect.  

    Specific temperature measurement principle: radiation temperature measurement is based on Planck's law, Wien's law and so on.  When any object is heated, due to the vibration of internal atoms, it changes with the change of temperature. Externally, the object will emit radiation waves of various frequencies after being heated. Radiation method is to calculate the heating temperature of the object according to the wavelength or frequency of the emission spectrum of the object when heated.  Since the emissivity of different materials and objects with different shapes is different, the emissivity needs to be corrected to get the results.