Imaging for Borehole Wall by a Cylindrical Linear Phased Array

• Published in: Chinese physics letters Vol. 27; no. 9; pp. 119 - 122
• Main Author: 张碧星 师芳芳 吴先梅 宫俊杰 章成广
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.09.2010
• Subjects: CLPA; 压电元件; 均匀分布; 成像测井; 电力系统控制; 相控线阵
• ISSN: 0256-307X; 1741-3540
• DOI: 10.1088/0256-307X/27/9/094301

A new ultrasonic cylindrical linear phased array （CLPA） transducer is designed and fabricated for the borehole wall imaging in petroleum logging based on the previous theoretical researches. First, the CLPA transducer, which is made up of numbers of the piezoelectric elements distributed on the surface of a cylinder uniformly, is designed and fabricated. By transmitting and receiving acoustic waves with 16 active elements and using different groups of the elements under the control of the electric system, the CLPA can scan all areas of the borehole wall dynamically and rapidly without a traditional mechanism around the borehole axis. Then, the theoretical and experimental investigations are conducted in detail for the borehole wall scanning and imaging by the steel pipe and casing borehole with defects distributed in different shapes and directions. It is shown by experiments that the CLPA transducer has good focusing characteristic and good resolution for the borehole wall imaging in acoustic logging.