Intermodal Freight Transport - Containers and Container Handling

Containers and Container Handling

Containers, also known as intermodal containers or ISO containers because the dimensions have been defined by ISO, are the main type of equipment used in intermodal transport, particularly when one of the modes of transportation is by ship. Containers are 8-foot (2.4 m) wide by 8-foot (2.4 m) high. Since introduction, there have been moves to adopt other heights, such as 8-foot-6-inch (2.59 m), 9-foot-6-inch (2.90 m) and 10-foot-6-inch (3.20 m). The most common lengths are 20 feet (6.1 m) nominal or 19 feet (5.8 m) - 10+1⁄₂ in (0.27 m) actual, 40 feet (12 m), 48 feet (15 m) and 53 feet (16 m), although other lengths exist. In countries where the railway loading gauge is sufficient, truck trailers are often used. Variations exist, including open-topped versions covered by a fabric curtain are used to transport larger loads. A container called a tanktainer, with a tank inside a standard container frame, carries liquids. Refrigerated containers are used for perishables.

Handling equipment can be designed with intermodality in mind, assisting with transferring containers between rail, road and sea. These can include:

• Transtainers for transferring containers from sea-going vessels onto either trucks or rail wagons. A transtainer is mounted on rails with a large boom spanning the distance between the ship's cargo hold and the quay, moving parallel to the ship's side.
• Gantry cranes, also known as straddle carriers, are able to straddle rail and road vehicles, allowing for quick transfer of containers. A spreader beam moves in several directions allowing accurate positioning of the cargo.
• Grappler lift, which is very similar to a straddle carrier.
• Reach stackers are fitted with lifting arms as well as spreader beams and lift containers to swap bodies or stack containers on top of each other.
• Sidelifters are a road-going truck or semi-trailer with cranes fitted at each end to hoist and transport containers in small yards or over longer distances.
• Swap body units are not strong enough to be stacked, but they have folding legs under their frame but they can be moved between trucks without using a crane.