A merchant ship, merchant vessel, trading vessel, or merchantman is a watercraft that transports cargo or carries for hire. This is in contrast to Boating, which are used for personal recreation, and , which are used for military purposes.
They come in a myriad of sizes and shapes, from inflatable in Hawaii, to 5,000-passenger Riverboat casino on the Mississippi River, to plying New York Harbor, to oil tankers and at major ports, to passenger-carrying in the Caribbean.
Many merchant ships operate under a "flag of convenience" from a country other than the home of the vessel's owners, such as Liberia and Panama, which have more favorable maritime laws than other countries.
The Greek merchant marine is the largest in the world. Today, the Greek fleet accounts for some 16 per cent of the world's tonnage; this makes it currently the largest single international merchant fleet in the world, albeit not the largest in history.
During wars, merchant ships may be used as auxiliaries to the navy of their respective countries, and are called upon to deliver military personnel and materiel.
History
Definitions
The term "commercial vessel" is defined by the United States Coast Guard as any vessel (i.e. boat or ship) engaged in commercial
trade or that carries passengers for hire.
In English, the term "Merchant Navy" without further clarification is used to refer to the British Merchant Navy; the United States merchant fleet is known as the United States Merchant Marine.
Name prefixes
Merchant ships' names have a prefix to indicate which kind of vessel they are:
Merchant ship categories
The UNCTAD review of maritime transport categorizes ships as: oil tankers, bulk (and combination) carriers, general cargo ships, container ships, and "other ships", which includes "liquefied petroleum gas carriers, liquefied natural gas carriers, parcel (chemical) tankers, specialized tankers, reefers, offshore supply, tugs, dredgers, cruise, ferries, other non-cargo". General cargo ships include "multi-purpose and project vessels and Roll-on/roll-off cargo".
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Cargo ship
A cargo ship or freighter is any sort of
ship or vessel that carries
cargo, goods, and materials from one port to another. Thousands of cargo carriers ply the world's seas and oceans each year; they handle the bulk of international trade. Cargo ships are usually specially designed for the task, often being equipped with cranes and other mechanisms to load and unload, and come in all sizes.
Bulk carrier
A bulk carrier is a
ship used to transport
bulk cargo items such as
iron ore, bauxite, coal, cement, grain and similar cargo. Bulk carriers can be recognized by large box-like hatches on deck, designed to slide outboard or fold fore-and-aft to enable access for loading or discharging cargo. The dimensions of bulk carriers are often determined by the ports and sea routes that they need to serve, and by the maximum width of the Panama Canal. Most lakes are too small to accommodate bulk carriers, but a large fleet of
has been plying the
Great Lakes and St. Lawrence Seaway of
North America for over a century.
Container ship
Colombo Express built in 2005]]A container ship is a cargo ship that carries its cargo in standardized containers, in a technique called
containerization. These ships are a common means of commercial intermodal freight transport.
Tanker
A tanker is a
ship designed to transport
liquids in bulk. Tankers can range in size from several hundred
tonnage, designed to serve small harbours and coastal settlements, to several hundred thousand tons, with these being designed for long-range haulage. A wide range of products are carried by tankers, including:
Different products require different handling and transport, thus special types of tankers have been built, such as , , and Gas carrier.
Among oil tankers, were designed for carrying oil around the Horn of Africa from the Middle East; the FSO Knock Nevis being the largest vessel in the world, a ULCC supertanker formerly known as Jahre Viking (Seawise Giant). It has a deadweight of 565,000 metric tons and length of about . The use of such large ships is in fact very unprofitable, due to the inability to operate them at full cargo capacity; hence, the production of supertankers has currently ceased. Today's largest oil tankers in comparison by gross tonnage are TI Europe, TI Asia, TI Oceania, which are the largest sailing vessels today. But even with their deadweight of 441,585 metric tons, sailing as VLCC most of the time, they do not use more than 70% of their total capacity.
Apart from pipeline transport, tankers are the only method for transporting large quantities of oil, although such tankers have caused large environmental disasters when sinking close to coastal regions, causing . See , Erika, Exxon Valdez, Prestige and for examples of tankers that have been involved in oil spills.
Coastal trading vessel
Coastal trading vessels are smaller ships that carry any category of cargo along coastal, rather than trans-oceanic, routes. Coasters are shallow-hulled
used for trade between locations on the same island or continent. Their shallow hulls allow them to sail over
and other submerged navigation hazards, whereas ships designed for blue-water trade usually have much deeper hulls for better
seakeeping.
Passenger ship
A passenger ship is a ship whose primary function is to carry passengers. The category does not include
cargo ship which have accommodations for limited numbers of passengers, such as the formerly ubiquitous twelve-passenger freighters in which the transport of passengers is secondary to the carriage of freight. The type does however include many classes of ships which are designed to transport substantial numbers of passengers as well as freight. Indeed, until recently virtually all
were able to transport mail, package freight and express, and other cargo in addition to passenger luggage, and were equipped with cargo holds and derricks, kingposts, or other cargo-handling gear for that purpose. Modern
cruiseferry have
for lorries as well as the passengers' cars. Only in more recent
and in virtually all
has this cargo capacity been removed. A
ferry is a
boat or
ship carrying passengers and sometimes their vehicles. Ferries are also used to transport freight (in
Truck and sometimes unpowered freight
Containerization) and even
(in the case of a
train ferry).
See also
