A Giant-Magnetoresistance Sensor for Magnetic-Flux-Leakage Nondestructive Testing of a Pipeline

Research paper by L. Chen, P.-W. Que, T. Jin

Indexed on: 01 Jul '05Published on: 01 Jul '05Published in: Russian Journal of Nondestructive Testing


This paper presents the method of magnetic-flux-leakage (MFL) detection and the characteristics of a giant-magnetoresistance (GMR) sensor. An experimental apparatus that uses a GMR sensor for oil-pipeline inspection is described. A permanent-magnet assembly was used to excite MFL signals. The signal from the GMR sensor is preamplified with an appropriate gain. The result shows the magnetic-flux-leakage method based on a GMR sensor can detect small defects in an oil pipeline.