FEASIBILITY STUDY ON NON-DESTRUCTIVE TESTING FOR FATIGUE CRACK DETECTION OF CORNER WELD

This study reviews the non-destructive testing methods and evaluates their reliability and adaptability for the detection of fatigue cracks which develop from a blowhole at the root of the corner weld. X-ray, ultrasonic, magnetic particle, liquid penetrant, and eddy current testing methods are provided. For the internal crack, ultrasonic testing appears to be desirable. Minimum crack sizes detectable are about 8mm∅ with a high accuracy. For the crack opened to the surface, eddy current and magnetic particle testing give a fair estimation. But it must be understood that fatigue cracks will be missed by liquid penetrant testing.