The bucket wheel can reach a diameter of up to 6 meters. For instance, a 1,600 kW bucket-wheel dredger might utilize the Ellicott DWE120 model-a dual-bucket-wheel assembly with a diameter of 3,317 mm, a rotational speed of 13 rpm, a shaft power of 186 kW, and a total cutting force of 10 tonnes, all driven by hydraulic motors. The dual-bucket-wheel configuration allows for equally efficient operation in both left and right directions; the dredger can work continuously and efficiently regardless of whether it is swinging to the left or right, thereby increasing productivity and offering distinct advantages when dredging side slopes.
The rotational axis of the bucket wheel is arranged at a specific angle relative to the support arm, distinguishing it from the parallel configuration found in cutter-suction dredgers. Specifically, the bucket wheel's rotational axis is angled relative to the support arm, whereas the rotational axis of a cutter-suction dredger's cutter head runs parallel to the support arm. Cutter-suction dredgers typically operate by swinging left and right around a central spud (positioning pile).
The hull is generally a non-self-propelled steel rectangular barge structure, with an overall length of up to 87.6 meters and a molded breadth of 18 meters. For example, some bucket-wheel dredgers feature a non-self-propelled, sectional welded box-type hull equipped with a spud carriage, underwater dredge pump, inboard dredge pump, and anchor boom system. The main inboard dredge pump is driven directly by the main diesel engine via a reduction gear and clutch, while the underwater pump is hydraulically driven; the hydraulic pumps are powered by diesel engines. The entire vessel is centrally controlled from the bridge, featuring operating, positioning, and surveying systems, along with a full suite of instrumentation; key control system components are sourced from Siemens (Germany) or Omron (Japan). Deck machinery includes port and starboard anchor-lifting winches on the main deck at the bow, port and starboard anchor booms and lateral shift anchors, as well as port and starboard 400 kN lateral shifting winches. The vessel's stern is equipped with a main spud, a main spud carriage, and an auxiliary spud. The main spud positions the vessel, while the carriage-using the main spud as a reaction point-pushes the vessel forward along the centerline of the dredged trench with a stroke of 6 meters; the auxiliary spud temporarily holds the vessel in position after the carriage completes a working stroke.
