A container ship is a ship that carry all of its cargo in standardized truck-size containers. A container is either 20 or 40 feet long, 8 feet wide and 8 or 8,6 feet high. To increase revenues, “high cube” containers with heights of 9’6″ have come into common use. Fortunately, most container ships can carry containers of mixed heights without significant difficulty.  Containerships generally carry a mix of 20′ and 40′ containers, and some are fitted for deck stowage of 45′ and 48′ lengths.

Over the years goods transported in containers has increased and is increasing due to the flexibility and easy of cargo handling at port. One example is that containers are taking over the Reefer market. Today, approximately 90% of non-bulk cargo worldwide is transported by container. Containers ships is also many time referred to as “Box-Ships”

Container ship size & Classes

Container ships have constantly been growing in size and today they are seriously competing with the ULCC Tankers of being the largest ships in the world. It is the economy-of-scale that is driving the growth in ship size. Unlike the Bulker and Tanker segment Container ships are defined by its capacity in number of containers they able to carry. The term used is TEU and is an abbreviation from Twenty Feet Equivalent Units. One of the first container ships, the US Ideal X, owned by Malcom Mclean, had a capacity of 58 containers in on its first voyage in April 1956. Today´s largest Container ship deveivered 2007, the Emma Maersk,  officially have a capacity of 11 000 TEUs and is 357 meters long & 56 m wide. Industry sources however estimates the capacity to be between 13 000 – 15 000 TEUs. Today the industry is looking into construction even larger ships, 18 000+ TEUs.

Panamax: ≈4 500 – 5 000 TEU

Post Panamax: ≈5 000 – 10 000 TEU

Suezmax: ≈10 000 -15 5000 TEU

Post Suezmax: ≈15 500 TEU< (This ship type does not exist yet but is being discussed)

Container Designed & Type

General Design

Containers are generally designed with either one or two medium speed engines or slow-speed (2-stroke)  engines depending on ship size. Design speed is about 15 – 27 knots. In general bigger ships needs go faster due longer port stay for offloading. Smaller vessel can be (geared) equipped with equipment for self offloading of containers while the larger gearless ships is dependent on port equipment.

ULCS

Abbriviation of “Ultra Large Container Ship” and today are able to carry more than 10 000 TEU. Speed is usually 25 + knots and the vessels are gearless.

Container Feeder vessel

Typically between 500 – 1 700 TEU and operates between ports within a continent i. e. the northern european ports. Design speed is 15 – 21knots and there are both geared and gearless types.

More information about container ships could be found here or here.