A general term applied to ships intended for carriage of both oil and dry cargoes in bulk. These cargoes are not carried simultaneously, except for oil retained in slop tanks. The design of a combination carrier is similar to a conventional bulk carrier but such a ship is equipped with pipelines, pumps and inert gas plant. See also Tri- Cargo Carrier.
- Oil/Bulk/Ore (OBO) carrier – A single-deck ship of double skin construction, with a double bottom, hopper side tanks and topside tanks fitted below the upper deck and intended for the carriage of oil or dry cargoes, including ore, in bulk.
OBO carrier SKS SKANA can carry three grades of cargo in seven tanks, all of which are coated with tar epoxy, and fitted with a deepwell pump. These are supplied from power packs driven by individual diesel engines.
- Ore/Oil carrier – A single-deck ship having two longitudinal bulkheads and a double bottom throughout the cargo region and intended for carriage of ore cargoes in the centre holds or oil cargoes in the centre holds and wing tanks.