INTERGRANULAR OXIDATION DETECTING APPARATUS AND INTERGRANULAR OXIDATION DETECTING METHOD

PROBLEM TO BE SOLVED: To provide an intergranular oxidation detecting apparatus and an intergranular oxidation detecting method for determining whether an intergranular oxide is present on the surface of a hot-rolled steel sheet after acid cleaning.SOLUTION: An intergranular oxidation detecting apparatus according to the present invention for a hot-rolled steel sheet after acid cleaning includes: a first radiation thermometer; a second thermometer capable of measuring the temperature of the hot-rolled steel sheet after acid cleaning irrespective of the thermal emissivity; and a mechanism for determining whether an intergranular oxide is present on the basis of the temperature measured with the first radiation thermometer and the temperature measured with the second thermometer, and an intergranular oxidation detecting method according to the present invention for a hot-rolled steel sheet after acid cleaning includes: measuring a first temperature of a hot-rolled steel sheet after acid cleaning with a first radiation thermometer; measuring a second temperature of the hot-rolled steel sheet after acid cleaning with a second thermometer capable of measuring the temperature irrespective of the thermal emissivity; and determining whether an intergranular oxide is present on the basis of the first temperature and the second temperature.SELECTED DRAWING: Figure 1 【課題】本発明は、酸洗後の熱延鋼板表面の粒界酸化物の有無を判定できる粒界酸化検出装置及び粒界酸化検出方法を提供することを課題とする。【解決手段】本発明に係る酸洗後の熱延鋼板の粒界酸化検出装置は、第１放射温度計と、上記酸洗後の熱延鋼板の温度を熱放射率に拘わらず測定可能な第２温度計と、上記第１放射温度計の測定温度及び第２温度計の測定温度に基づいて粒界酸化物の有無を判定する機構とを備えることを特徴とする。本発明に係る酸洗後の熱延鋼板の粒界酸化検出方法は、第１放射温度計により酸洗後の熱延鋼板の第１の温度を測定する工程と、熱放射率に拘わらず温度測定可能な第２温度計により酸洗後の熱延鋼板の第２の温度を測定する工程と、上記第１の温度と第２の温度とに基づいて粒界酸化物の有無を判定する工程とを備えることを特徴とする。【選択図】図１