CAMERINI, C.; REBELLO, J. M. A. ; BRAGA, LUCAS ; SANTOS, R. W. ; SANTOS, J. M. C. ; PEREIRA, G. R. .
Resumo: Rigid pipelines installed in offshore structures for oil and gas production are built from pipe sections connected by circumferential welds. Such welds are generally points of stress concentration and therefore the regions that most demand periodic inspection. The weld geometry and the inspection speed required for in service inspection are the main challenges associated to the inspection procedure. In the present work an eddy current transducer with sensing coils placed orthogonally and connected in differential mode was introduced to evaluate fatigue cracks in weld root. A dedicated embedded electronic hardware was developed to drive the transducer and measure the electrical complex impedance of the coils and was specifically designed for operation under autonomous in-line inspection tool in a speed range between 0.5 – 1.0 m/s. The achieved results have confirmed that the introduced eddy current transducer is a potential solution for fatigue crack detection in irregular surfaces like weld root, while the hardware developed presented a reasonable SNR and achieved the data rate required to be incorporated in an autonomous in-line inspection tool.
