Improved Ultrasonic Inspection Techniques for Creviced Safe Ends

摘要

Described in this report are several developments which have been key factors leading to improved ultrasonic inspection techniques for detection of IGSCC in the creviced region of Boiling Water Reactors recirculation inlet safe ends.nSafe ends removed from an operating plant are used along with metallurgical studies to determine ultrasonic sizing capabilities on real cracks resulting in improved ultrasonic procedures and the design of calibration blocks which better reflect true geometric conditions encountered in the field.nApplication of improved ultrasonic techniques using improved calibration block containing geometric reflectors and calibration notches detected IGSCC in 9 of 10 recirculation inlet nozzle safe ends examined.