Abstract
The article describes real cases where dangerous axial vibration of ship shafting occurred. The vibration occurrence mechanism is considered on the basis of the fluctuating deformation of the crank in the main engine crankshaft with the provision of the methodical background for its calculation and normalization. The differential equations for natural and forced axial oscillations are shown to be derived from similar equations for torsional ones. However, as opposed to the torsional vibration axial shafting vibration acts directly on the ship's hull through the thrust bearing. Shaft stresses occurring due to the axial vibration are shown to be too small to be used as an admissibility parameter, so it is preferable to control axial vibration by amplitude. The article also provides a summary analysis of the requirements of Classification Societies for axial shafting vibration.
Keywords: shafting, axial vibration, torsional vibration, damper, internal combustion engine
References
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About authors
Rumb Viktor - PhD, professor, St. Petersburg State Marine Technical University, 3, Lotsmanskaya st., 190121, St. Petersburg, Russia
Hoang Van Tu - St. Petersburg State Marine Technical University, 3, Lotsmanskaya st., 190121, St. Petersburg, Russia
Serov Aleksey - PhD, FAI "Russian Maritime Register of Shipping", 8, Dvortsovaya naberezhnaya, 191186, St. Petersburg, Russia
Issue: 46/47 (2017)
For citation: V.K. Rumb, Hoang Van Tu, A.V. Serov. Modern view on axial vibration of ship propulsion unit shafting. Research Bulletin by Russian Maritime Register of Shipping. 2017, No. 46/47, pp. 82-86.
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