PURPOSE: To provide an ultrasonic inspection method for a cylindrical metal component such as a repaired stub tube of a boiling water reactor.
CONSTITUTION: In order to measure the dimension of a crack 26 in almost the radial direction within cylindrical metal components 14, 16, an interface 30 for reflecting ultrasonic energy is formed at one end of the cylindrical metal component, an ultrasonic conversion means 24 is arranged on the inside of the cylindrical metal component, pulse ultrasonic energy is sent from the ultrasonic conversion means to the interface at the specified angle against the interface, the pulse ultrasonic energy is reflected on the interface so as to pass through the main body of the cylindrical metal component in almost the axial direction, and the pulse ultrasonic energy which is reflected by the crack 26 and returned to the ultrasonic conversion means is detected. By utilizing the interface, the crack is scanned in the radial direction by the displacement in the vertical direction of the ultrasonic conversion means.
JIEEMUZU CHIYAN SHIE TAN
JIEEMUZU HAWAADO TAAHAN
JIERARUDO ARAN DEIIBAA
