Steel containers for shipping are manufactured in a small number of standard sizes for certain specific purposes. While standard sizes for these ubiquitous mobile containers range from 10ft to 45ft, the most commonly used sizes are the 20ft container and the 40ft container.
The ISO standards specify the overall dimensions of steel containers as well minimum internal dimensions and the size of door openings. The sizes of any general purpose (GP) 20ft and 40ft container should be:
- 20ft container:
- Overall dimensions: Length 20 feet (6.058 m), width 8 feet (2.438 m), height 8 feet 6 inches (2.591 m).
- Minimum internal dimensions: Length 19 feet 41/8 inches (5.898 m), width 7 feet 8½ inches (2.350 m), height 7 feet 8½ inches (2.350 m).
- Minimum door opening dimensions: Width 7 feet 8 inches (2.337 m), height 7 feet 5 inches (2.261 m).
- 40ft container:
- Overall dimensions: Length 40 feet (12.192 m), width 8 feet (2.438 m), 8 feet 6 inches (2.591 m).
- Minimum internal dimensions: Length 39 feet 5½ inches (12.029 m), width 7 feet 8½ inches (2.350 m), height 7 feet 8½ inches (2.350 m).
- Minimum door opening dimensions: Width 7 feet 8 inches (2.337 m), height 7 feet 5 inches (2.261 m).
Both the 20ft and 40ft container are also available as high cube (HC) GP containers. These are the same length as ordinary GP steel containers but they are higher. Both the 20HC and 40HC mobile containers are 9 feet 6 inches (2.896 m) high.
Why Choose a 40ft Container?
Generally, 40-foot dry freight, GP shipping containers are made completely of welded steel except for the floors which are usually made of load-bearing marine-grade plywood, although some do have steel floors. The thick, steel double doors at one end (like those of 20-foot dry freight mobile containers) are weather-sealed and absolutely secure. The mobile containers themselves are freestanding and totally self-contained, and may be used for shipping, for storage, and converted shipping containers can even be used for accommodation.
GP mobile containers are used for dry freight of all kinds, from rocks to food, clothing, and even vehicles. Obviously, you will choose a container that provides sufficient space (in terms of volume) for the goods you need to transport, and a 40ft container has double the capacity to a 20ft container. But another element that must be considered is payload. This is generally 20 tons. If mobile containers are overloaded in terms of their carrying capacity (measured in weight) that provides revenue for the carrier, there will be a “heavy weight surcharge”.
For this reason, 20-foot containers are commonly used to carry heavy goods, like iron ore or rock, while a larger 40ft container, with the same payload, will be used to transport lighter products. And of course, you will be able to squeeze even more into a 40ft high cube container. These are the largest size steel containers currently used by shipping lines on a routine basis.
Almar has storage and dry freight and mobile containers as well as converted containers. Contact us for container rental prices.
