West of England P and I

The slewing ring attached to the rotating crane body will be subject to the most wear at the rear of the crane body opposite the jib and under the jib itself, the former being subject to tension and the latter to compression caused by the weight of the jib and loads suspended from the hook.

The principal causes leading to failure of a crane slewing ring bearings are lack of lubrication of the bearings and inadequate monitoring of the bearing wear down.

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