Parametric Study on the Pipeline Stress Detection of Magnetostrictive Guided Wave

Abstract

The corrosion of pipelines caused by concentrated stress is a main cause of pipeline leakage when long-distance oil pipelines are laid in complex environment. Regular inspection of pipeline stress can prevent the further aggravation of pipeline corrosion caused by stress at early minor defects. Aiming at the problem of pipeline stress damage detection, this research simulatesthe pipeline stress detection based on the magnetostrictive guided wave technology. Firstly, on the basis of the echo signal generated at the defect location of the pipeline, the solution process of the electromagnetic field of the ferromagnetic material is analyzed by the physical equation. Secondly, the stress detection model of straight pipe segment is built with the help of COMSOL software. Finally, the effect of depth, width and excitation frequency of the corrosion defect on the stress state are analyzed by finite element simulation. The results show that the magnetic induction strength inside the ferromagnetic material determines the strain size of the material under the action of an external magnetic field. Under the same excitation condition, the stress at the defect increases with the depth of the defect and decreases with the increase of the axial width. Under the condition that the defect is unchanged, the stress increases with the increase of the excitation frequency, and decreases with the increase to a certain extent. In this paper, a method of stress detection with magnetostrictive guided wave is presented to realize the purpose of concentrated stress detection at early defects, which is of significance to reduce the risk of pipeline leakage.