ULTRASONIC FLAW DETECTING SURVEY INSTRUMENT FOR NUCLEAR REACTOR PRESSURE VESSEL

摘要

PROBLEM TO BE SOLVED: To provide an ultrasonic flaw detecting survey instrument for a nuclear reactor pressure vessel that can ultrasonically detect and inspect a flaw of a nozzle-drum weld part while avoiding an obstruction by remote operation even when a member provided near a nozzle of a nuclear reactor pressure vessel becomes an obstruction to ultrasonic flaw detection and inspection. SOLUTION: In an ultrasonic flaw detecting survey instrument for ultrasonically detecting a flaw of a nozzle weld part of a nuclear reactor pressure vessel by a probe module 50, a fixed arm 30 is erectly provided at a base 20 moving along the periphery of a nozzle, and a moving arm 40 is provided movably in the longitudinal direction along the fixed arm 30. This moving arm 40 is provided with the probe module 50 so as to move longitudinally. When the moving arm 40 interferes with an obstruction, the moving arm 40 is moved by remote operation, and the whole arm is shortened to avoid the obstruction.