This paper describes a method of evaluating the structural integrity of rocket motor cases using Acoustic Emission (AE) technique. The AE technique is used to monitor the defects during proof pressure testing of rocket motor casings made of M250 maraging steel, that is highly fracture sensitive. An acceptance criterion developed based on specimen level testing has been used for assessing the integrity of the motor cases during the proof pressure test. The AE data acquired from 45 rocket motor casings during proof pressure testing is analysed to characterise the quality of each motor case. AE parameters like amplitude, duration of the signal, event roll-off, event rate etc., are considered for the analysis. The data pertaining to each of these parameters has been analysed as per the acceptance criterion. Based on this analysis, the motor cases could be classified into various categories. Further, this information has been used to standardise the qualification criterion.
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 2427 - 2432 Publisher:Ashgate Publishing Company
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