FIELD APPLICATION TECHNIQUE OF MONITORING SYSTEM FOR BEARINGS IN ROTATING MACHINERY USING ACOUSTIC EMISSION
Min-Hwa Chung, Yong-Sang Cho, Sang-Guk Lee and Dong-Jin Yoon* Korea Electric Power Research Institute *Korea Research Institute of Standards and Science
Keywords: Acoustic Emission, NDT of bearings, condition, monitoring
ABSTRACT
For the continuous monitoring and the earlier detection of abnormal conditions of the journal bearing in rotating machinery for power plants, a system for their diagnosis by acoustic emission(AE) was developed and applied to actual power plants. It was found from the field application study as well as the laboratory experiment using a simulated journal bearing system that AE RMS voltage was the most efficient parameter for the purpose of current study. Based on the above results, algorithms and judgement criteria for the diagnosis system was established. The system in composed of four parts as follows: the sensing part including AE sensor and preamplifier, the signal processing part for RMS-to-DC conversion to measure AE rms voltage, the interface part for transferring RMS voltage data into PC using A/D converter, and the software part including the graphic display of bearing conditions and the diagnosis program. At present, the system is so composed that it can simultaneously control no.5, no.6 internal combustion engines in North-Chejoo power plant, and it is available for the on-line monitoring of journal bearings.
Publication Source: Trends in NDE Science & Technology; Proceedings of the 14th World Conference on Non-Destructive Testing, New Delhi, 8-13 December 1996.Vol. 4, pages 2537 - 2542 Publisher:Ashgate Publishing Company
NDTnet
