Automatic magnetic particle testing system for square billets

A new magnetic particle testing system using image processing has been developed for the task of detecting surface defects of square billets, instead of being done manually, at Kokura Steel Works. The system has been used in a square billets inspection and grinding line since July 1993 and has contributed to its fully automatic operation so that the number of operators for inspection can be reduced. The system is 100% accurate in detecting the defects which are more than 0.3 mm deep in real time.