Long Tons (long-ton) to Tons (t) conversion

What is the Long Ton?

The long ton is a unit of mass in the British imperial system, historically used for weighing bulk commodities such as coal, ore, and shipping cargo. It is equal to 2,240 pounds and remains familiar in the United Kingdom and in maritime contexts.

Definition

The long ton is defined as exactly 2,240 pounds avoirdupois. Since one pound equals 0.45359237 kg exactly, its SI value is:

$$1\ \text{long-ton} = 1016.05\ \text{kg}$$

Equivalently, the long ton equals 20 hundredweight (cwt) of 112 lb each, distinguishing it from the 2,000 lb US short ton and the 1,000 kg metric tonne.

Origin and History

The long ton descends from the medieval English "tun," a large cask used to ship wine, whose full weight was standardized in trade. The avoirdupois system fixed the hundredweight at 112 pounds (eight stone of 14 lb), and twenty of these made the ton, giving 2,240 lb. This "long" hundredweight and ton became the standard for British commerce and were carried throughout the Commonwealth and colonial trade.

Law and Notable Facts

The long ton is the British/imperial ton, contrasted with the 2,000 lb US short ton and the 1,000 kg metric tonne (megagram). It is legally recognized in the United Kingdom, though the metric tonne has largely replaced it for official trade. Notably, the long ton (1016 kg) sits remarkably close to the metric tonne (1000 kg), differing by only about 1.6%, which is why "ton" and "tonne" are often used loosely as near-equivalents in shipping.

Real-World Examples and Conversions

• A long ton equals 1016.05 kg, about 16 kg heavier than a metric tonne.
• Ship displacement and cargo were traditionally quoted in long tons; a 10,000 long ton vessel carries roughly 10,160 metric tonnes.
• One long ton (2,240 lb) is 240 lb heavier than one US short ton (2,000 lb), a 12% difference.
• A long ton of coal (1016 kg) is a typical unit still cited in older British mining and heating records.

What is Tons?

Tons are a unit of mass, primarily used for measuring heavy objects. However, there are different types of tons, each with a slightly different weight. The most common are the metric ton, the short ton (or US ton), and the long ton (or UK ton). This document aims to give more insights for each of the ton measure.

Types of Tons

• Metric Ton (tonne): The metric ton, also known as a tonne, is defined as 1,000 kilograms.
• Short Ton (US Ton): The short ton, or US ton, is defined as 2,000 pounds.
• Long Ton (UK Ton or Imperial Ton): The long ton, also known as the UK ton or imperial ton, is defined as 2,240 pounds.

Conversion Between Tons

Here's how to convert between the different types of tons:

• 1 metric ton = 1,000 kg ≈ 2,204.62 lbs ≈ 1.102 short tons ≈ 0.984 long tons
• 1 short ton = 2,000 lbs ≈ 907.185 kg ≈ 0.907 metric tons ≈ 0.893 long tons
• 1 long ton = 2,240 lbs ≈ 1,016.05 kg ≈ 1.016 metric tons ≈ 1.12 short tons

$$1 \text{ metric ton } = 1000 \text{ kg}$$

$$1 \text{ short ton } = 2000 \text{ lbs}$$

$$1 \text{ long ton } = 2240 \text{ lbs}$$

Origin and History

The term "ton" has its roots in the Old English word "tun," which referred to a large cask or barrel. Over time, it evolved to represent a unit of weight based on the capacity of such a barrel, typically used for wine or other goods. The different types of tons arose due to variations in measurement systems between countries and industries.

Real-World Examples

• Shipping: Cargo ships often measure their carrying capacity in metric tons.
• Mining: The extraction and trade of ores, like iron ore, are frequently quantified in metric tons.
• Construction: Materials like concrete and steel are often ordered and priced by the ton.
• Agriculture: Crop yields, such as wheat or corn, can be measured in tons, especially on a large scale.
• Waste Management: Municipal waste and recycling amounts are often reported in tons.

Interesting Facts

• The metric ton is part of the International System of Units (SI).
• The term "tonnage" is often used in the shipping industry to refer to a vessel's cargo-carrying capacity, although it doesn't always directly correspond to weight in tons. Instead, it can relate to volume or other measures.
• The abbreviation for metric ton is "t," while short ton is often abbreviated as "ST" and long ton as "LT" to avoid confusion.

Notable Associations

While no specific law or person is directly associated with the ton as a unit of measurement, its use is deeply embedded in various industries and regulations related to trade, transportation, and commerce. For example, international trade agreements often specify quantities of goods in metric tons.