Erosion Identification and Assessment of a Steel Pipeline Using EMI Technique

Abstract

Gas and oil transmission pipelines have a very good safety record. This is because of their good design, better type of materials used, and good operating practices. However, like any other engineering structure, pipelines are subjected to failure due to many problems. One such problem is an erosion of pipelines. Erosion is a process along the timeline in which the pipeline material is degraded due to high impact from any kind of abrasive material on the pipeline initiating metal loss which ultimately reduces its strength and decreases its load-bearing capacity. Electromechanical impedance (EMI) method is a recent nondestructive evaluation technique which is effectively employed nowadays for structural health monitoring (SHM). Whether be it damaged or undamaged condition of the structure, PZTs are used to evaluate the response of the host structure. In the present study, an experimental setup comprising of a part of the pipeline is examined which is subjected to eroding action through a shot-blasting equipment. The EMI technique employed in the present research is suitable for damage identification due to erosion. Metal wire-based technique is used, as PZT cannot be directly bonded to the curved surface like a pipe. Root-mean-square deviation (RMSD) index is calculated for quantifying and evaluation of damages. This study is aimed at the structural health monitoring of pipeline structures which are subjected to erosion.