Long ton | |
---|---|

Unit system | Imperial units, U.S. customary units |

Unit of | Mass |

In base units | 2,240 lb |

Conversions | |

1 in ... | ... is equal to ... |

SI base units | 1,016.047 kg |

Metric tons | 1.016047 t |

Short tons | 1.12 short tons (exactly) |

**Long ton**,^{ [1] } also known as the **imperial ton** or **displacement ton**,^{ [1] }^{ [2] } is the name for the unit called the "ton" in the avoirdupois system of weights or Imperial system of measurements. It was standardised in the thirteenth century. It is used in the United Kingdom and several other British Commonwealth of Nations countries alongside the mass-based metric tonne defined in 1799, as well as in the United States for bulk commodities.^{[ citation needed ]}

It is not to be confused with the short ton, a unit of weight equal to 2,000 pounds (907.18474 kg ) used in the United States, and in Canada before metrication, also referred to simply as a "ton".

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 hundredweight (cwt), each of which is 8 stone (1 stone = 14 pounds). Thus a long ton is 20 × 8 × 14 lb = 2,240 lb.

A long ton, also called the **weight ton** (W/T),^{ [1] }**imperial ton,** or **displacement ton,** is equal to:

- 2,240 pounds or 1,016 kilograms or 1.016 metric tons
- 12% more than the 2,000 pounds of the North American short ton
- the weight of 35 cubic feet (0.99 m
^{3})^{ [2] }of salt water with a density of 64 pounds per cubic foot (1.03 g/cm^{3})^{ [1] }

It remains in use in the United States, most commonly in measuring the displacement of ships, the volume-to-carrying-weight of fuels, and in trade of baled commodities^{ [1] } and bulk goods like iron ore and elemental sulfur. The long ton was the unit prescribed for warships by the Washington Naval Treaty of 1922—for example battleships were limited to a displacement of 35,000 long tons (36,000 t; 39,000 short tons).

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 of 1985.^{ [3] }^{ [4] }

The long ton remains in informal use by some heritage rail companies and remains on a limited number of weight limit signs on roads (usually in remote areas away from major towns and cities where tonnes are used).^{[ citation needed ]}

The **pound** or **pound-mass** is a unit of mass used in the imperial, United States customary and other systems of measurement. Various definitions have been used; the most common today is the international avoirdupois pound, which is legally defined as exactly 0.45359237 kilograms, and which is divided into 16 avoirdupois ounces. The international standard symbol for the avoirdupois pound is **lb**; an alternative symbol is **lb _{m}**,

The **ton** is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of mass. Its original use as a measurement of volume has continued in the capacity of cargo ships and in terms such as the freight ton. Recent specialised uses include the ton as a measure of energy and for truck classification. It is also a colloquial term.

The **tonne** is a non-SI metric unit of mass equal to 1,000 kilograms. It is commonly referred to as a **metric ton** in the United States. It is equivalent to approximately 2,204.6 pounds, 1.102 short tons (US) or approximately 0.984 long tons (UK). The official SI unit is the **megagram**, a less common way to express the same mass.

**United States customary units** are a system of measurements commonly used in the United States. The **United States customary system** developed from English units which were in use in the British Empire before the U.S. became an independent country. However, the United Kingdom's system of measures was overhauled in 1824 to create the imperial system, changing the definitions of some units. Therefore, while many U.S. units are essentially similar to their imperial counterparts, there are significant differences between the systems.

**Tonnage** is a measure of the cargo-carrying capacity of a ship. The term derives from the taxation paid on *tuns* or casks of wine. In modern maritime usage, "tonnage" specifically refers to a calculation of the volume or cargo volume of a ship. Tonnage should not be confused with displacement, which refers to the actual weight of the vessel. Tonnage is commonly used to assess fees on commercial shipping.

A **bushel** is an imperial and US customary unit of volume based upon an earlier measure of dry capacity. The old bushel was equal to 2 kennings (obsolete), 4 pecks or 8 dry gallons and was used mostly for agricultural products such as wheat. In modern usage, the volume is nominal, with bushels denoting a mass defined differently for each commodity.

The **hundredweight**, formerly also known as the **centum weight** or **quintal**, is an English, imperial, and American unit of weight or mass of various values. Its value differs between the American and imperial systems. The two values are distinguished in American English as the "short" and "long" hundredweight and in British English as the "cental" and the "imperial hundredweight".

The **short ton** is a *mass* measurement unit equal to 2,000 pounds-mass. Its usage is confined to the United States, where it is known as simply a common *ton*.

The **stone** or **stone weight** is an English and imperial unit of mass now equal to 6.35 kg (14 pounds).

A **system of measurement** is a collection of units of measurement and rules relating them to each other. Systems of measurement have historically been important, regulated and defined for the purposes of science and commerce. Systems of measurement in use include the International System of Units (SI), the modern form of the metric system, the imperial system, and United States customary units

**Deadweight tonnage** or **tons deadweight** (DWT) is a measure of how much weight a ship can carry, not its weight, empty or in any degree of load. DWT is the sum of the weights of cargo, fuel, fresh water, ballast water, provisions, passengers, and crew.

**English units** are the units of measurement that were used in England up to 1826, which evolved as a combination of the Anglo-Saxon and Roman systems of units. Various standards have applied to English units at different times, in different places, and for different applications.

The earliest recorded systems of weights and measures originate in the 3rd or 4th millennium BC. Even the very earliest civilizations needed measurement for purposes of agriculture, construction, and trade. Early standard units might only have applied to a single community or small region, with every area developing its own standards for lengths, areas, volumes and masses. Often such systems were closely tied to one field of use, so that volume measures used, for example, for dry grains were unrelated to those for liquids, with neither bearing any particular relationship to units of length used for measuring cloth or land. With development of manufacturing technologies, and the growing importance of trade between communities and ultimately across the Earth, standardized weights and measures became critical. Starting in the 18th century, modernized, simplified and uniform systems of weights and measures were developed, with the fundamental units defined by ever more precise methods in the science of metrology. The discovery and application of electricity was one factor motivating the development of standardized internationally applicable units.

Both the imperial and United States customary systems of measurement derive from earlier English systems used in the Middle Ages, that were the result of a combination of the local Anglo-Saxon units inherited from German tribes and Roman units brought by William the Conqueror after the Norman Conquest of England in 1066.

**Dimensional weight**, also known as **volumetric weight**, is a pricing technique for commercial freight transport, which uses an estimated weight that is calculated from the length, width and height of a package.

**Builder's Old Measurement** is the method used in England from approximately 1650 to 1849 for calculating the cargo capacity of a ship. It is a volumetric measurement of cubic capacity. It estimated the tonnage of a ship based on length and maximum beam. It is expressed in "tons **burden**", and abbreviated "tons bm".

The **units of transportation measurement** describes the unit of measurement used to measure the quantity and traffic of transportation used in transportation statistics, planning, and their related fields.

The **displacement** or **displacement tonnage** of a ship is its weight based on the amount of water its hull displaces at varying loads. It is measured indirectly using Archimedes' principle by first calculating the volume of water displaced by the ship then converting that value into weight displaced. Traditionally, various measurement rules have been in use, giving various measures in long tons. Today, metric tonnes are more used.

**Ship measurements** consist of a multitude of terms and definitions specifically related to ships and measuring or defining their characteristics.

The **Imperial and US customary measurement systems** are both derived from an earlier English system of measurement which in turn can be traced back to Ancient Roman units of measurement, and Carolingian and Saxon units of measure.

- 1 2 3 4 5 "Definitions, Tonnages and Equivalents".
*Military Sealift Fleet Support Command Ships*. Archived from the original on 25 May 2017. Retrieved 11 September 2016. - 1 2 Dictionary.com -
*"a unit for measuring the displacement of a vessel, equal to a long ton of 2240 pounds (1016 kg) or 35 cu. ft. (1 cu. m) of seawater."* - ↑ legislation.gov.uk: Weights and Measures Act 1985 Retrieved 17 January 2013.
- ↑ A Dictionary of Weights, Measures, and Units, edited by Donald Fenna, Oxford University Press

This page is based on this Wikipedia article

Text is available under the CC BY-SA 4.0 license; additional terms may apply.

Images, videos and audio are available under their respective licenses.

Text is available under the CC BY-SA 4.0 license; additional terms may apply.

Images, videos and audio are available under their respective licenses.