Murayama, Riichi; Fukuoka Kogyo Daigaku; Japan
Murayama, R.; Fukuoka Institute of Technology; Japan
Sun, F.; Tsinghua University; China
Sun, Z.; Tsinghua University; China
Chen, Q.; Tsinghua University; China
Session: Guided Waves techniques 3
Time: 09:40 - 10:00
Nondestructive inspection of a high-temperature structure is required to guarantee its safety. However, there are no useful sensors for high-temperature structures. Some of them cannot work at temperatures over 50℃.Another concern is that they are too expensive to use. Therefore, a sensing system, which can transmit and receive a Lamb wave and an SH-plate wave alternately using an electromagnet and travel a long distance using a long waveguide, has been studied. This means that an ultrasonic sensor could be driven at atmospheric temperature.
Next, we tried to transmit and receive a guided wave into a pipe using a long wave guide for inspecting pipes at high temperatures. Actually, the other end of the wave guide was wound in a circumferential direction around the pipe surface using any types of fixtures. In particular, it has been confirmed that the T(0,1)-mode guide wave could be generated and received in the case that the ultrasonic source is a Lamb wave and L(0,2)-mode guide wave could be generated and received when the ultrasonic source is the SH0-plate wave. Finally, a drilled hole with a 10 mm diameter machined into a pipe could be detected. The results indicated that the development technology could be applied to a high temperature pipe in a nuclear power plant.