Supply vessel
These supply vessel include handling the anchors and mooring chains for drilling rigs, towing of rigs and platforms together with subsequent positioning on site, and platform supply duties. The required bollard pull has a powerful influence on the design, since this defines the power need, the propeller size, hull shape and depth aft to give the necessary propeller immersion. Hull beam and shape shall give good stability, particularly when heavy moorings and anchors are suspended from the stern. Anchor handling requires high power, winch capacity, deck space aft, storage bins for rig chains and auxiliary handling equipment. A stern roller is used to ease the passage of wires and anchors over the stern of the vessel during deploying or weighing of the anchor.