Types of Shipping Containers

Conex boxes were first developed during the Korean War that started in 1950. They were used for transportation and storage of war supplies such as food and artillery. Conex boxes were also used in the Vietnam war for the same purposes.

It was Malcolm McLean, an American transport entrepreneur, that developed the conex box into the modern intermodal shipping container as we know it today. This reinvention revolutionized the transport industry and international trade ever since.

The container is credited for reducing transport costs significantly. It is used to handle bulk amounts of cargo which reduces handling costs. Handling supplies in small quantities was expensive. Conex boxes have also improved reliability by reducing clutter. They ensure minimal loss or damage of cargo while handling. Intermodal containers have safety features that help reduce cargo theft.

All these factors have contributed to the shortening of transit time and therefore reduction of inventory costs. Today, international trade can be carried out efficiently and effectively because of these boxes. The name conex came from the Container Express (CONEX) box system developed in early 1950 to help with logistics. Conex box and intermodular shipping containers are terms that are used interchangeably. The containers are also referred to as cargo containers, freight containers, ISO containers, shipping containers, container vans, and sea can.


Standardized containers made of steel first used the d in the second half of the 1940s. They were first developed by shipping companies ad the U.S. military. During World War II, the U.S. Army realized that war supplies were taking too long at the ports. This was because such cargo had to be loaded and offloaded in small bits. They could not afford to have such delays. The levels of pilferage and damage of supplies while in transit were just unacceptable. They had to do something about it.

Their first standardized container, the transporter, was developed in 1948 and could carry a little over 8,000 pounds of cargo. It had a volume of over ten cubic meters and was made of corrugated steel. One end was fitted with double doors and the top four corners were fitted with lifting rings. It was mounted on the skids.

They also developed a half size container. Conex boxes could be stacked up to three high. They were made in a way that protected the contents from being damaged by the elements. By the time America went to war with Vietnam, the U.S.A had close to 200,000 conex boxes.

Engineer Keith Tantlinger made significant contributions to the development of trailers used to transport connex boxes. By performing some design modifications, he changed them from their stressed skim aluminum material design to a stronger model that could carry up to 200 containers stacked two high. He also contributed to improved handling by putting steel castings on the top corners of the containers. This made lifting of containers easier.

Tantlinger also developed automatic spreaders that were used for lifting containers while loading and offloading. The spreaders were also used for packing unitized cargo into the containers. The engineer is also credited for designing the twist-lock mechanism. This mechanism is used to lock a container tightly on a ship, train or truck. The twist-lock connects with corner castings to form a standard rotating connector that secures shipping containers into place.

The international maritime organization came up with ISO standards for containers starting in 1968. ISO standards improved consistency in transportation, loading and offloading all around the globe. This has facilitated efficiency in local and international trade.

The Inter-governmental Maritime Consultative Organization came up with The International Convention for Safe of Containers regulation in 1972. This regulation seeks to ensure safety in handling and transportation of containers. It mandates that containers being transported in internationally should have a CSC Safety-approval plate. This plate provides vital information about the container. Such information includes container’s age, registration number, weight and dimensions, strength and maximum stacking capability. Shippers struggled with adhering to these standards, but there have been significant improvements in compliance over the years.

Recent Developments

They are fitted with a plywood floor. Using corrugated steel makes the boxes rigid and strong enough for stacking. It also makes the containers heavy, and this creates an aerodynamic drag during transportation. Their standard length is usually either twenty or forty feet.

Cargo is usually packed tightly in this containers, and the containers are appropriately arranged in ships or yards, by stacking them up. This avoids cluttering. Cargo becomes unitized and therefore easier to handle and move. Comex boxes do have some standard features, such as handling and stacking fittings, for shipping efficiency. They also have identifying features, individual unique reporting marks, to facilitate easier identification. Today, there are over 20 million intermodal containers around the world. Most of the world’s seaborne trade is aided, in one way or another, by shipping containers.

ISO approved containers have castings equipped on all eight corners of the container. The box can therefore be lifted from above, below or sideways. The castings have openings for twist-lock fasteners and these containers can be stacked up to ten high. Intermodal containers used in road and rail transport are usually stacked up to three units high.

Even though containers are made of the very strong material, it is not uncommon for them to flex during transportation. Containers are normally used for shipping for over ten years. China is the leading manufacturer of containers in the world.