FLAW DETECTING METHOD DUE TO LEAKAGE FLUX AND LINE FOR DETECTING FLAW OF STEEL SHEET

• Main Authors: MATSUFUJI YASUHIRO, NAKAI KATSUNORI
• Format: Patent
• Language: English
• Published: 21.07.2005
• Edition: 7
• Subjects: AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKINGWITHOUT ESSENTIALLY REMOVING MATERIAL; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES,OTHERWISE THAN BY ROLLING; MEASURING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; PERFORMING OPERATIONS; PHYSICS; PUNCHING METAL; TESTING; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a flaw detecting method due to a leakage flux capable of inexpensively preventing the over-detection of the edge of a steel sheet without installing a steel sheet meandering control device for preventing the meandering of the steel sheet, and a line for detecting the flaw of the steel sheet. SOLUTION: In the flaw detecting method by the leakage flux for sensing the leakage flux caused by the flaw of the steel sheet to detect the flaw of the steel sheet, the edge of the steel sheet is detected by a CCD camera and the abnormal signal emitted from the edge of the steel sheet is masked. In the line for detecting the flaw of the steel sheet using a leakage flux type flaw detector for detecting the flaw of the steel sheet by sensing the leakage flux caused by the flaw of the steel sheet, the CCD camera for detecting the edge of the steel sheet is arranged and the leakage flux type flaw detector is equipped with a means for masking the signal based on the leakage flux detected at the part corresponding to the position of the edge of the steel sheet based on the position of the detected edge of the steel sheet. COPYRIGHT: (C)2005,JPO&NCIPI