An Automatic Pinhole Inspection System for Cold Rolled Strip

摘要

There are many pinhole inspection systems available in steel industry. But most of them suffer from edge dead band (undetectable area near strip edge), and to solve this problem they use edge mask to prevent lights from diffracting near strip edge. In this paper we introduce the new pinhole inspection system for cold roiled strip without edge mask. The inspection system uses 4 CCD cameras as detection sensors with two kinds of different detection sensitivities, and halogen lamp guided by optical fiber as light sources. By this hybrid configuration, the inspection system can detect pinholes up to 10 mu m at strip speed of 1000 mpm, but also has virtually no edge dead band without edge mask equipment.