Pipe Defect Detection with Remote Magnetic Inspection and Wavelet Analysis

• DOI: 10.1007/s11277-017-4092-8
• Publication Date: 2017-03-16T16:29:23Z
• Authors: Qiang Song; Weixia Ding; He Peng; Jijun Gu; Jian Shuai
• Keywords: SIGNAL (programming language); Canalisation

High-pressure pipeline has significant magneto-mechanical effect in the geomagnetic field. Combined with magnetic inspection technology on the ground, the magnetic anomalies induced by buried pipeline defects can be detected and then be analyzed. But in remote inspection condition, the signal to noise ratio of magnetic signal is too low, and the pipeline magnetic anomalies will be obscured in the complex magnetic background. The difficulty for non-excavation pipeline detection is how to separate its magnetic anomalies from remote magnetic signals. In this paper, a nonlinear structural finite element analysis model was created for pipeline magnetic testing and the properties of three components of the magnetic field are investigated. The Φ220 mm × 10 mm pipe was detected under the conditions of 8 MPa pipe pressure and 2 m inspection distance, and a signal processing method based on wavelet analysis was also proposed. Experiment results showed that the magnetic anomalies induced by pipe cracks with different depth could be recognized.