In this post we’re focusing on what shipping containers are made of: materials and components.


  • Structure
    The corrugated walls, frame, cargo doors, and cross members of shipping containers are all made from Corten steel.
    Corten steel (often referred to as Cor–Ten) is a weather resistant steel which could more accurately be termed as an “Atmospheric Corrosion Resistant Steel”. It is a copper chromium alloy steel – this alloy displays a greater level of resistance to atmospheric weathering when compared to other unalloyed steels.
    In practice, this steel is also developed to eliminate the need for painting.
    Container manufactures use this material because it also possesses the physical properties that make it weldable and rust resistant.
    Rust-resistance means that should a piece of paint chip off of the steel, rust will form at the surface but go no deeper.
  • Floor
    Most shipping containers come with marine-grade plywood flooring. The flooring is infused with a small amount of insecticides to prevent six-legged stowaways from joining the container’s voyage. These insecticides do not aerosolize and are only a risk to hungry bugs, not to the people and goods who come in contact with the flooring.


  • Corner Castings
    The reinforced corners of shipping containers are called corner castings.
    Corner castings have openings for twist lock connections that allow them to be connected to other containers or to anchor points.
    They’re also designed to be strong enough for crane rigging (to be lifted by rigging to a crane), even when fully loaded.
  • Twist Locks
    Twist locks securely connect shipping containers to anchor points or to other containers. The end piece of the twist lock fits into the corner casting and then pivots to a locked position, usually via a lever.
  • Cross Members
    Beams, or joists, called cross members support the shipping container floor. The space the cross members creates between the ground and the flooring prevents moisture from seeping into the container from underneath.
    The cross members lift the structures away from the ground and mitigate the risk of damage caused by natural elements.
  • Forklift Pockets
    Standard 20-foot containers and many 40-foot containers come with two openings along the bottom edge of the structures, called forklift pockets.
    As their name implies, forklift pockets are reinforced slots designed to accommodate forklift tines. Forklifts can insert the tines into the pockets in order to lift and move the structures.
  • Cargo Doors
    A storage container’s cargo doors are the two steel doors most often found at one end of the container (though some shipping containers have cargo doors on both ends, or even have cargo door side walls).
    Cargo doors were designed to prevent theft and weather intrusion on long voyages and offer formidable security for the assets contained in them.
    The door’s locking mechanism is very simple in some particular units specially designed for storage, like Arctic Store and Superstore.
  • CSC Plate
    CSC is an acronym used to indicate The International Convention for Safe Containers. This convention is a set of standards for shipping container design intended to prevent structural failure and protect human life.
    For example, shipping containers loaded with tens of thousands of pounds of cargo are often stacked several units high, and a collapse in a port or at sea could be catastrophic to employees working below.
    The CSC plate affixed to the shipping container certifies a qualified inspector has examined that container and confirmed that it can safely carry cargo.
    The container has to be examined before its 5th year anniversary after manufacturing in order to mantain the CSC certification, applying the ACEP sticker on this plate.
    In addition, after the 5th year of life, most of Marine Carriers and Port Terminals in Italy require for Shipper’s Owned containers an additional certificate of compliance that is issued (after physical inspection) by Registro Italiano Navale (RINA) or Bureau Veritas (Star Service can arrange it for the buyer).

As you can see, shipping containers are relatively simple structures, making them the ideal base for shipment or storage.
The wide range of containers we can supply to our customers is suitable for all needs: contact us for further information!

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