A crane ship is a ship with a crane specialised in lifting heavy loads. The largest crane ships are used for construction on the deep sea. Conventional single-body cranes are used, but the largest cranes are often catamarans or semi-submersible ships because they have increased stability.
Sheerleigh- A granty crane has a fixed crane and cannot be rotated, so the crane is oriented towards the load. The world record in lifting loads is held by the Saipem 7000 crane with 12,500 tons lifted.