Development of automatic flaw detection system for magnetic particle indications by the dry powder method

Magnetic particle examination (MT) has been widely used as a nondestructive technique for examining surface flaws in ferritic steel components. However, the evaluation of the examination depended on the testing personnel's eyesight resulting in the missing of flaws and lack of reliability. Automatic flaw detection is highly desirable to improve the reliability of the examination. We have, therefore, developed an automatic MT system of the dry powder method for welds in nuclear components making use of a video camera and an image processor. This report describes the automatic MT system and its functional test results. The system is capable of examining test objects at a speed of 2 m/min. (author)