Effect of Lift-off on Pipeline Magnetic Flux Leakage Inspection
نویسندگان
چکیده
On pipeline magnetic flux leakage (MFL) inspection, welds and debris are present in all pipelines and cause lift-off of the sensors and/or the magnetizer of the magnetic flux leakage inspection tool, and have the potential to affect the acquired magnetic flux leakage data. By adopting ANSYS software to simulate the effect of lift-off on the MFL signal. The results of this research indicate that lift-off (sensor, magnetizer, and both) causes a reduction on the peak magnetic flux leakage amplitude, sensor lift-off has a substantially greater effect on the peak magnetic flux leakage amplitude than magnetizer lift-off of the same magnitude, lift-off of sensors and magnet simultaneously produces the greatest reduction in measured peak magnetic flux leakage amplitude. Better to understand the effect that lift-off has on MFL inspection results will improve the quality of the magnetic flux leakage inspection data and result integrity assessment in defect.
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