TEMPERATURE MEASURING METHOD AND TEMPERATURE MEASURING DEVICE OF STEEL PLATE, AND TEMPERATURE CONTROL METHOD OF STEEL PLATE

摘要

A method and a device capable of measuring the temperature of a steel plate with high precision over a long period without being influenced by variations in radiation rate of a steel plate under measurement or a change with time in radiation rate of a reference plate (reflector), with installation of a measuring device being facilitated as compared with a measuring method utilizing multiple reflection. A high precision temperature control method of steel plate is also provided. A reference plate (2) equipped with a temperature controller (5) is disposed oppositely to a steel plate (1) in order to measure a reference plate temperature T₂ directly by a contact thermometer (6), and a radiation thermometer (7) is disposed to face the steel plate (1) at such an angle that radiation energy is reflected alternately once or twice respectively between the reference plate (2) and the steel plate (1). Degree of emission from the steel plate (1) is measured by the radiation thermometer (7), a degree of emission temperature T_g is determined by expressing the degree of emission in terms of the temperature of a black body radiating energy equivalent to the degree of emission, and the temperature controller (5) controls the reference plate temperature T₂ so as to match the degree of emission temperature T_g which is employed as the temperature of the steel plate.