| 摘要 |
<p>PROBLEM TO BE SOLVED: To manufacture a coil having a defect marking which can reliably and easily discriminate harmful defects irrespective of presence/absence the adhesion of the rust preventive on a surface of a steel plate without generating any flaws in the steel plate by the defect marking. SOLUTION: A steel plate continuous treatment line comprising a surface defect meter to detect surface flaws and an ink marker device to mark the position of defects with ink comprises the steps of continuously treating the steel plate, detecting the surface flaws in the steel plate by the surface defect meter, operating the name, the length and the grade of the defect based on the information on the detected flaw, discriminating harmful defects, defects difficult to discriminate, and harmless defects, and marking the harmful defects and the defects difficult to discriminate with ink at the positions of the defects when the harmful defects and the defects difficult to discriminate reach the ink marker device.</p> |
