The long ton, also known as the imperial ton, displacement ton,Dictionary.com - ''"a unit for measuring the displacement of a vessel, equal to a long ton of 2240 pounds (about 1016 kg) or 35 cu. ft. (1 cu. m) of seawater."'' or British ton, is a measurement

unit Unit may refer to: General measurement * Unit of measurement, a definite magnitude of a physical quantity, defined and adopted by convention or by law **International System of Units (SI), modern form of the metric system **English units, histo ...

equal to 2,240 pounds (1,016.0 kg). It is the name for the unit called the "

ton Ton is any of several units of measure of mass, volume or force. It has a long history and has acquired several meanings and uses. As a unit of mass, ''ton'' can mean: * the '' long ton'', which is * the ''tonne'', also called the ''metric ...

" in the

avoirdupois Avoirdupois (; abbreviated avdp.) is a measurement system of weights that uses pounds and ounces as units. It was first commonly used in the 13th century AD and was updated in 1959. In 1959, by international agreement, the definitions of the p ...

system of weights or Imperial system of measurements. It was standardised in the 13th century. It is used in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

for bulk commodities. It is not to be confused with the

short ton The short ton (abbreviation: tn or st), also known as the US ton, is a measurement unit equal to . It is commonly used in the United States, where it is known simply as a ton; however, the term is ambiguous, the single word "ton" being variously ...

, a unit of weight equal to used in the United States, and Canada before

metrication Metrication or metrification is the act or process of converting to the metric system of measurement. All over the world, countries have transitioned from local and traditional Unit of measurement, units of measurement to the metric system. This ...

, also referred to simply as a "ton".

Unit definition

A long ton is defined as exactly 2,240 pounds. The long ton arises from the traditional British measurement system: A long ton is 20

long hundredweight The hundredweight (abbreviation: cwt), formerly also known as the centum weight or quintal, is a British imperial and United States customary unit of weight or mass. Its value differs between the United States customary and British imperial sys ...

(cwt), each of which is 8

stone In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition, and the way in which it is formed. Rocks ...

Thus, a long ton is

Unit equivalences

A long ton, also called the weight ton (W/T), imperial ton, or displacement ton, is equal to: * * exactly 12% more than the 2,000 pounds of the North American

, being 20 long hundredweight (112 lb) rather than 20 short hundredweight (100 lb) * the weight of of salt water with a density of

Usage around the world

United Kingdom

To comply with the practices of the European Union, the British Imperial ton was explicitly excluded from use for trade by the United Kingdom's

Weights and Measures Act A weights and measures act is a kind of legislative act found in many jurisdictions establishing technical standards for weights and measures. Notable acts of this type include: * Various Weights and Measures Acts (UK) or the various legislative ...

of 1985. The measure used since then is the tonne, equal to 1,000 kilograms. If still used for measurement, then the word "ton" is taken to refer to an imperial or long ton.

United States

In the United States, the long ton is commonly used in measuring the

displacement Displacement may refer to: Physical sciences Mathematics and physics *Displacement (geometry), is the difference between the final and initial position of a point trajectory (for instance, the center of mass of a moving object). The actual path ...

ship A ship is a large watercraft, vessel that travels the world's oceans and other Waterway, navigable waterways, carrying cargo or passengers, or in support of specialized missions, such as defense, research and fishing. Ships are generally disti ...

s and the shipping of

bale Bale may refer to: Apps Bale Messenger, an Iranian instant messaging (IM) app owned by the National Bank of Iran Packaging * Cotton bale * Hay or straw bale in farming, bound by a baler * Paper bale, a unit of paper measurement equal t ...

d commodities and bulk goods like

iron ore Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the f ...

and elemental

sulfur Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms ...

International

The long ton was the unit prescribed for

warship A warship or combatant ship is a naval ship that is used for naval warfare. Usually they belong to the navy branch of the armed forces of a nation, though they have also been operated by individuals, cooperatives and corporations. As well as b ...

s by the

Washington Naval Treaty The Washington Naval Treaty, also known as the Five-Power Treaty, was signed during 1922 among the major Allies of World War I, Allies of World War I, which agreed to prevent an arms race by limiting Navy, naval construction. It was negotiated at ...

of 1922; for example,

battleship A battleship is a large, heavily naval armour, armored warship with a main battery consisting of large naval gun, guns, designed to serve as a capital ship. From their advent in the late 1880s, battleships were among the largest and most form ...

s were limited to a displacement of . The long ton is traditionally used as the unit of weight in international contracts for many bulk goods and commodities.

References

{{Imperial units Units of mass Ton, long Customary units of measurement in the United States