Journal of Vibration Testing and System Dynamics 8(4) (2024) 417--427 | DOI:10.5890/JVTSD.2024.12.004

Dattatraya R Hipparkar, Sunil Chandel

Defence Institute of Advanced Technology, Pune - 411025, India

Abstract

Shock isolation is a critical issue from the point of view of the problem of weapons stored inside submerged platforms from severe underwater shocks. The shock loads may result from the underwater explosion of a nuclear warhead, mines, and bomb nearby submerged platform. These underwater explosions would generate shock loads up to several hundred g's and must protect weapons from severe damage to keep them operational under such circumstances. The most efficient method for reducing shock levels transferred to weapons is shock isolation, which has received little attention from many researchers. Therefore, an Elastic rail shock isolator (ERSI) design was implemented to isolate underwater weapons stored inside submerged platforms to certain acceptable limits. In this study, the prototypes of ERSI were manufactured, and tests were carried out to investigate the isolation effectiveness under laboratory test conditions. The experimental setups were designed, and tests were performed on the universal shock test machine (USTM) equipped with instrumentation to measure the parameters during shock motion, i.e., acceleration and relative displacement of mass. On USTM, a shock input of 170g for 3 ms was characterized, and prototypes were subjected to shock tests to evaluate the performance of ERSI. Finally, the data collected during the shock test was analyzed and compared with analytical results to conclude on isolation performance of ERSI. Thus, the weapon protection was qualified for increasing combat reliability and endurance under attack.

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