A pipe inspection system using ultrasonic guided wave with inter-digital transducer was developed. In this system, for uni-directional transmission, a pair of transducer is set axially on the pipe with a separation of one-quarter of the wavelength, and a one-quarter period delayed anti-phased waveforms are applied to the pair. By this method, the amplitude of the syn thetic traveling wave in the minus direction can be completely decreased to zero in theory. For 50A pipe specimen, artificial discontinuities...
英字タイトル:
A Pipe Inspection System Using Ultrasonic Guided Wave

真庭 一彦 Kazuhiko MANIWA Guided wave inspection technique is effective for detecting defects like corrosion in piping, because it can perform long range inspection. It is possible to expect this inspection as a metho d that leads to the decrease of the inspection process and its cost, because the incidental work can be reduced. Especially, the contraction effect of the inspection work is extensive in larg e-diameter piping inspection. In this paper, we introduce the guided wave inspection system to large-d...
英字タイトル:
Wall Thinning Inspection Technique for Large-Diameter Piping using Guided Wave

Underwater inspection vehicles for nuclear power plants were selected as the third maintenance heritage. Hitachi- GE Nuclear Energy, Ltd and Toshiba Energy Systems & Solutions Corporation have been working on miniaturization and weight reduction of vehicles for many years, and enabling visual inspection of narrow space and bottom of the nuclear reactors, which were not accessible with the conventional hanging cameras. This article describes the developed vehicles by each company and their contribution to ma...
英字タイトル:
The Third Maintenance Heritage Underwater Inspection Vehicles for Nuclear Power Plants

An ultrasonic measurement method has been developed to determine the crystal growth angle of a unidirectional solidification material by using an ultrasonic array probe. The crystal growth direction of a unidirectional solidified nickel based superalloy are derived within an error of ±5 degrees by evaluating wave height levels of echoes measured with focal laws of each assumed crystal growth angle. Moreover, high precision ultrasonic testing is realized based on the focal laws considering the acoustic anis...
英字タイトル:
Development of Ultrasonic Phased Array Testing Method for Unidirectional Solidification Materials