水下管道超声导波检测实验研究

Experimental Investigation of Underwater Pipeline Inspection Using Ultrasonic Guided Waves

扭转模态导波T(0,1)对液体载荷不敏感,其用于水下管道检测是一种具有潜在吸引力的导波模态。基于T(0,1)导波,研制了一套可用于水下管道检测的新型换能器阵列,并在实验室环境中进行了系列检测实验。换能器采用厚度剪切型压电陶瓷作为敏感元件。卡具装置采用模块化设计,模块间通过销轴连接。这种设计使换能器阵列具有一定的柔性,并可方便拆卸各模块以满足不同直径管道对于换能器数量的要求。实验结果表明,换能器阵列能在水下管道中高效激励和接收T(0,1)模态导波。模拟损伤回波信号到达时间和幅度较好地反映了损伤的轴向位置及大小。换能器阵列具有安装简单,使用灵活的特点,为水下管道超声导波检测提供了有效手段。

The torsional guided wave T（0,1） is an attractive mode to use for underwater pipeline inspection because this mode is not sensitive to liquid loading. A novel piezoelectric transducer array for the detection of corrosion in underwater pipelines using T（0, 1） mode is developed and a series of tests are carried out in the laboratory environment. The transducer employs thickness shear mode piezoelectric ceramic as the sensitive element. The holding device is modular in design, and the modules are connected.with other by a pin. This design method makes the transducer array has a certain flexibility, and the modules can be easily disassembled to satisfy the number of transducers for various diameter pipelines. The results show that the transducer array can efficiently excite and receive the T（0,1） mode in underwater pipeline. The echo signal from artificial notch correlated well with the notch size and location. The transducer system has the advantages of simple installation and flexible use, and provides an effective means for the underwater pipeline inspection using guided waves.