Corrosion of the bottom of the petroleum tank may lead to a product leak that could cause a fire or explosion resulting in damage to people and the environment, therefore the test of tank bottom corrosion is necessary to be conducted periodically to prevent the occurrence of the above problems. In non-destructive inspection, the Magnetic Flux Leakage (MFL) method relies on the variation of fluxes caused by defects on the surface of materials to detect corrosion, pitting, or imperfections, which is proved quite effectively with low cost. The project was implemented to develop a prototype of the MFL bottom detection device based on the research results in the world to improve corrosion survey capacity in industrial equipment, as well as to improve the expertise in the Research Team of electronics and automation in the fields of magnetic fields and sensors. As a result, an MFL model using permanent magnets and Hall sensors were fabricated. Survey experiments showed that the machine could detect corrosion defects up to 20% of steel wall thickness in the scanning speed range from 500 mm/s to 1130 mm/s. However, to meet the actual survey needs, the team must continue to improve the device in terms of sensitivity, scanning speed, the ability to operate automatically or semi-automatically, and register for a fire safety inspection.
References
Espina-Hernandez, J.W.; Hallen, J.M. (2010) Influence of Remanent Magnetization on Pitting Corrosion in Pipeline Steel. In Proceedings of the 8th International Pipeline Conference, Calgary, AL, Canada, pp. 565–572.
Feng, J.; Zhang, J.F.; Lu, S.X.; Wang, H.Y.; Ma, R.Z. (2013) Three-axis magnetic fluxleakage in-line inspection simulation based on finite-element analysis, 531–536.
Gloriaa, N.S.; Areiza, M.L. (2009) Development of a magnetic sensor for detection andsizing of internal pipeline corrosion defects, 669–677.
Isabel, C.P.; Jorge, H.A.; Gerd, D. (2014) Simulation for Magnetic Flux Leakage signalinterpretation: A FE-approach to support in-line magnetic pipeline pigging, pp.349–353.
J. C. Drury I.Eng. M.Ins NDT. (2015) Magnetic Flux Leakage Technology,SilverwingNDT (Uk) Limited.
Keshwani, R.T. (2009) Analysis of Magnetic Flux Leakage Signals of InstrumentedPipeline Inspection Gauge using Finite Element Method. IETE J. Res, 73–82.
Ke, M.Y.; Liao, P.; Song, X.C. (2010). Real-time Data Mining in Magnetic FluxLeakage Detecting in Boiler Pipeline. In Proceedings of the InternationalConference on Digital Manufacturing & Automation, Changsha, China, 18–20.
Kim, H.M.; Yoo, H.R.; Rho, Y.W.; Park, G.S. (2013) Detection method of cracks byusing magnetic fields in underground pipeline.