Damage detection of pipeline multiple cracks using piezoceramic transducers

To study the feasibility of detecting pipeline multi-cracks damage using piezoceramic transducers, the electromechanical impedance method and the stress wave based active sensing method were used respectively to perform the damage detection of pipeline with multi-cracks. In this research, the lead zirconate titanate (PZT) type transducers were used due to its strong piezoelectric effect and low cost. During the experiments, two artificial cracks on the pipeline specimen were created, ranging from 0 mm to 9 mm, and seven different operating conditions were generated for each artificial crack. In the monitoring test, for the electromechanical impedance method, the damage index based on Root Mean Square Deviation (RMSD) was used, and for the active sensing method, the damage index based on Wavelet Packet Energy Loss (WPEL) was used. In addition, the relationship between the crack depth and RMSD as well as the relationship between the crack depth and location and WPEL were analyzed. The results show that RMSD and WPEL indices increase with the increase of the depth of pipeline cracks. In addition, the WPEL index increases with the appearance of new cracks. Quantitative analysis of pipeline crack damage can be realized by electromechanical impedance method, and localization analysis on the pipeline multi-cracks damage can be achieved by stress wave method based on sensor arrays

Feasibility Study on Crack Detection of Pipelines Using Piezoceramic Transducers

Damage detection of pipelines is of great significance in terms of safety in the oil and gas industry. Currently, lead zirconate titanates (PZTs) are the most popular piezoceramic materials and show great potential in the applications of structural health monitoring. In this paper, the authors present a feasibility study on the crack detection and severity monitoring of pipelines using PZT transducers. Due to their electromechanical properties, the piezoceramic transducers can be either as an actuator or a sensor to generate or detect the stress wave. The active sensing approach was applied to monitor the crack severity of pipelines. The crack in the stress wave propagation path can be regarded as a stress relief, which reduces the received energy by the sensors. In the test, eight different operating conditions were tested in which one artificial crack was created ranging from 0 mm to 10.5 mm. A wavelet packet-based crack severity index was also built to quantitatively identify the pipeline damage condition at various crack depths