SHI Fangfang1  WU Xianmei1  KE Yijing1  ZHANG Bixing2

(1 State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences  Beijing 100190)

(2 School of Geophysics and Oil Resource, Yangtze University  Jingzhou  434023)

Received Oct. 27, 2009

Revised Nov. 24, 2009

Abstract An Ultrasonic Phased Array (UPA) transducer is presented for borehole imaging and casing inspection in acoustical logging. First, a Cylindrical Linear Phased Array (CLPA), which is made up of numbers of piezoelectric elements distributed on the surface of a cylinder uniformly, is designed and fabricated. By transmitting and receiving acoustic waves using different groups of elements under the control of the electric system, the CLPA can scan all area of the borehole wall dynamically and rapidly. Then the radiation and reflection acoustic fields of the CLPA are investigated theoretically in the casing borehole with defects. Finally, the experimental researches about ultrasonic scanning and imaging for the casing boreholes with defects have been conducted by the CLPA transducer. The experimental results consist well with the theoretical ones.