3D FEM of a pipeline with defect using MFL testing under extreme conditions

Corrosion monitoring of pipelines under extreme conditions (underwater and high temperature) is one of the important task to be carried out as corrosion is one of the leading causes of failure of steel structures mainly in pipelines. Magnetic Flux leakage testing technique is the most commonly used and cost effective method of estimating the extent of damage caused by corrosion in gas and oil transmission pipelines. In this paper, three dimensional simulation FEM model on corrosion inspection of various thickness of steel pipe using COMSOL software has been developed. The MFL signal (B z component) of defects, which have the same length, same width, and different depths, have been studied along with array sensors. The MFL signals have also been obtained experimentally through transmission of data using Radio frequency technique with an experimental set-up including the same pipe samples of various thickness measured along an axial line using hall effect and GMR sensor. This paper discusses in brief about the results obtained through FEM simulation and experiments done for data transmission which confirms the potential of the three-dimensional simulation for MFL inspection.