EMD of EMAT NDT in X70 Pipeline Weld Defects

Electromagnetic acoustic transducer (EMAT) is an emerging non-destructive testing technique which has been applied to the pipelines inspection. EMAT has advantages of Non coupling agent and can be used with high temperature environment. Due to the roughness remaining in surface of the pipeline, the quantitative analysis of defect location are challenges by using EMAT NDT. This paper introduces a new detection method of EMAT by hybriding Empirical Mode Decomposition (EMD) with IMFs reconstruction to quantitative detect weld defects. The new method has been validated to detect the defects of weld for the X70 pipeline by using Bulk-wave. Experiments have been proved that it improves the accuracy of the measurement, and achieve the recognition of millimeter-level defects.