New self-propelled mega-cutter dredger "d'Artagnan": Special features improve performance and flexibility. Advanced training simulator.
Type:
Presented during:
CEDA Dredging Days 2005 - Dredging: The Extremes, Rotterdam
Authors:
Keizer C. de; Gabriël J.; Clymans E. and Stroo S.
Abstract: Large cutter suction dredgers (CSD) frequently operate in open estuaries and at sea. Wave induced motions of the CSD generate additional forces on the “links” between the CSD and the sea bottom. The most important “link” is the spud (vertical steel tube) which is coupled to the CSD by means of the spud carrier. This coupling needs to be stiff to allow an efficient cutting process, but may not be too stiff, since the pontoon will irresistibly follow the movements of the longer waves and therefore high stiffness will inevitably lead to high forces in the links. The ideal is to create a variable stiffness – stiff in light wave conditions, flexible in rough wave conditions – and to decrease stiffness dramatically once the spud system is loaded beyond a certain limit. “D’Artagnan” is equipped with a spud carrier system capable to meet these requirements. CSD’s on one hand are used to excavate hard rocky materials (e.g. limestone, coral,..) and on the other hand to pump away relatively soft sea bottoms (sand, soft clay, silt,..). The dredging process -disintegration of the material, mixture formation of bottom material with seawater and pump process- behaves very differently in hard and in soft material. Conventionally a CSD is designed for optimum performance in hard soils or for optimum performance in soft material. “D’Artagnan” is optimised for both types of sea bottom material. In recent years large dredging projects requiring CSD’s on one hand pushed the industry to focus on the development and optimisation of CSD’s and hence on the ship-borne automated systems and on the other hand brought dredging crews, consisting partly of young men with little experience in the operation of CSD’s, back on board of CSD’s. To ensure optimum deployment of “d’Artagnan” and its new generation of automated systems additional focus on crew training is necessary. For this reason an advanced training simulator was developed together with “d’Artagnan”.
KEYWORDS : cutter suction dredger, flexible spud carrier, combination suction mouth/cutterhead, training simulator