Dynamic characterisation and modelling of a slew drive system of offshore cranes

Current dynamical models of the slewing motion of offshore cranes cannot predict the occurring vibrations during the design phase that arise during slewing. The relatively small pedestal crane on the Sleipnir experienced severe vibrations during the slewing motion in both the crane house and the boom, which were in the order of 1 and 5 Hz. As a...

3D motion compensation for an offshore crane: Assessing the feasibility for wind turbine maintenance

When working offshore on a floating vessel, the vessel will be subjected to wave induced motions and with a moving crane tip, a suspended load can start to swing. When the motions of the load become too large, the operation is interrupted. Alternatives such as jack-ups, function as a fixed platform to which the crane is attached, therefore...