MEASURING METHOD OF CAST SLAB SURFACE TEMPERATURE IN CONTINUOUS CASTING MACHINE

PROBLEM TO BE SOLVED: To precisely measure the surface temperature of a cast slab being cast while accurately understanding an end part of the cast slab, without affected by a secondary cooling water remaining on the surface of the cast slab, the steam generated from the secondary cooling water, and the white plume resulting from condensation of the steam.SOLUTION: The measuring method of the surface temperature of a cast slab is a measuring method for surface temperature of a cast slab in a continuous casing machine, in which the surface temperature of the cast slab 10 being continuously cast by an infrared sensing type surface temperature measuring instrument 13 is measured. An infrared sensing type surface temperature measuring instrument is used, in which a spreading field angle from the condenser lens of the infrared sensing type surface temperature measuring instrument is 0.1-2°. The distance between the condenser lens and the surface of cast slab is 100-800 mm. The gas of 10 NL/min or higher is jetted toward the cast slab from the surface temperature measuring instrument. The gas excludes the secondary cooling water and the vapor from between the condenser lens and the surface of cast slab as well as from a temperature measurement point of the cast slab.