METHOD FOR DETECTING FLAW OF CONTINUOUSLY CAST SLAB AND SYSTEM FOR DETECTING FLAW

PROBLEM TO BE SOLVED: To provide a method for detecting a flaw of a continuously cast slab, which can accurately detect a surface flaw of a cast slab that is cast continuously.SOLUTION: The method for detecting a flaw of a continuously cast slab includes: a setup step of preliminary setting the range that is obtained by excluding a predetermined length from each end in a width direction of the cast slab 18 that is cast continuously, as center parts 24, 25a, 25b, 26 of the cast slab 18; a measuring step of measuring a temperature distribution in a width direction of a surface of the cast slab 18 that is cast continuously; a temperature difference calculation step of calculating differences between maximum surface temperatures and minimum surface temperatures of the center parts 24, 25a, 25b, 26 of the cast slab 18 based on the measured temperature distribution; and a determination step of determining that a flaw is found in the cast slab 18 when the calculated difference becomes larger than a predetermined threshold or exceeds the predetermined threshold.