A bucket-wheel dredger has a rotating mechanical device, an excavator, perpendicular to the ship’s axis, mounted in front of the suction head.
The excavating head of the bucket-wheel contains 10 to 14 open or closed buckets. The working principle is similar to that of a cutter suction dredger but they are used for different purposes. They work in a stationary mode stabilised by either on spuds or anchors and have a continuously rotating system.
Bucket wheels are most often used for mining minerals in marine areas rather than dredging hard rock. Some are self-propelled to provide for transportation between work-sites.