2015. Vol.18. No. 3, pp. 40-42
AE Sources Localization Accuracy Improvement During Cross-country Gas Pipelines Testing
Method. The AE signal was simulated on the pipelines with wall thickness from 8 to 24 mm. A few types of transducers with different amplitude-frequency characteristics were chosen for signal detection. Further we analyzed forms of the detected AE signals and stability of their velocity.
Results. We have established that for each pipeline wall thickness there is a proper operation frequency range, within which the velocity of AE signals is stable and predictable. For example, for the 8 mm wall thickness the optimum frequency range is from 60 to 200 kHz. The suitable transducer for work within this range is GT200. If the work is held out of stated range, the AE signal velocity is not predictable and can vary from 500 to 5100 m/s; therefore localization of AE source turns to be impossible.
Keywords: acoustic emission, cross-country gas pipeline, acoustic emission transducer
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