PURPOSE: To furnish a device for inspecting abnormality of a pipe of small diameter incorporated in a steam condenser or the like from the inside of the pipe by an ultrasonic method by processing a detection signal with a device whose main component is a rotary scanning part of an ultrasonic probe.
CONSTITUTION: A rotary scanning part 4 of a probe is composed of a probe part 11 and a separate rotary driving part 13 for rotating the former for scanning, connected therewith by a flexible axis 12. The probe part is separated from the rotary driving part 13 so that noises on the side of a motor rotating the former have no effect on the side of the probe. Two probes 30A and 30B in a signal processing part divide the frequency of a reference oscillator of 4kHz by a synchronizing-signal generating circuit and are excited alternately by the repetition of 2kHz, thus performing the detection of flaws. When there is even a slight change in the inside shape of a pipe, noises are produced thereby, and from these noises a signal of the flaw is detected with discrimination.
SUZUKI AKIO
ITOU ATSUSHI
