Container ships are cargo ships that carry their entire load in truck-size intermodal containers, in a technique called containerization. They form a common means of commercial intermodal freight transport.
There are several key points in the design of modern container ships. The hull, similar to bulk carriers and general cargo ships, is built around a strong keel. Into this frame is set one or more below-deck cargo holds, numerous tanks, and the engine room. The holds are topped by hatch covers, onto which more containers can be stacked. Many container ships have cargo cranes installed on them, and some have specialized systems for securing containers on board.
The hull of a modern cargo ship is a complex arrangement of steel plates and strengthening beams. The hull is built around the keel. Resembling ribs, and fastened at right-angles to the keel are the ship's frames. The ship's main deck, the metal plate work that covers the top of the hull framework, is supported by beams that are attached to the tops of the frames and run the full breadth of the ship. The beams not only support the deck, but along with the deck, frames, and transverse bulkheads, strengthen and reinforce the shell. Another feature of recent hulls is a set of double-bottom tanks, which provide a second watertight shell that runs most of the length of a ship. The double-bottoms generally hold liquids such as fuel oil, ballast water or fresh water.
A ship's engine room houses its main engines and auxiliary machinery such as the fresh water and sewage systems, electrical generators, fire pumps, and air conditioners. In most new ships, the engine room is located in the aft portion of the ship.
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| General view of a typical container ship |
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| Container Ships guidelines for surveys |
