On the possibility of the application of magnetoacoustic emission intensity measurements for the diagnosis of thick-walled objects in the industrial environment

This paper presents the results of measurements of the magnetoacoustic emission (MAE) signal performed on thick-walled pipelines in the industrial environment, and discusses the possible ways of their further analysis. Even though the direct measurement of the MAE does not allow for the determination of the MAE intensity, the paper proves that it is possible to separate the useful signal from the background noise either by means of hardware analogue filtering or by the application of the numerical analysis of the signal. Both the fast Fourier transformation (FFT) and wavelet analysis allow for the characterization of the MAE signal, the intensity of which can be much lower than the background noise level. Implementation of the hardware filtering, even though resulting in a lower signal-to-noise ratio, allows us to measure only the useful data, simplifying greatly the analysis needed. It should be emphasized that the application of software made with the help of the LabVIEW package allows for the implementation of the numerical analysis directly in the measuring set, enabling thus the direct assessment of the correctness of the obtained results during the tests in the industrial environment.

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