In brief: What is Corten steel?
Corten steel is a weather-resistant structural steel used to manufacture shipping containers. The material is robust, weldable, and more resistant to the elements than standard structural steel.
When the surface is exposed, a solid patina forms under the right conditions. This layer slows down further corrosion. Additionally, a multi-layer paint finish protects the container from moisture, salt, and other environmental factors.
During their service life, shipping containers are exposed to rain, humidity, temperature fluctuations, and salty air. Corten steel withstands these stresses better than ordinary structural steel.
The material combines several key properties:
The corrugated walls further increase the structural stability. This keeps the container robust without becoming unnecessarily heavy.
No. Corten steel can also continue to corrode. The patina reduces the rate of corrosion but does not prevent rust entirely.
For a protective layer to form, the surface must be able to dry regularly. Constant moisture, standing water, aggressive chemicals, or high salt exposure can impair the protective effect.
Particularly critical factors include:
Under unfavorable conditions, the steel can rust significantly despite its special properties.
The paint provides additional protection against weather and corrosion. It also ensures a uniform surface and allows for the desired color scheme.
If the paint layer is damaged by impacts or scratches, the steel is exposed. Rust can form there. While weathering steel slows down the damage, it does not make repairs unnecessary.
Damaged areas of paint should be cleaned, prepared, and touched up with a suitable coating system.
Not every superficial spot of rust immediately compromises structural integrity. Flash rust or light surface rust may initially just be an aesthetic issue.
More critical are deep corrosion, pitting, flaking material layers, and weakened welded joints. Rust on corner posts, roof beams, floor beams, or corner castings should also be inspected carefully.
The depth, location, and extent of the corrosion are the deciding factors.
Loose paint, rust, and dirt must first be professionally removed. The surface is then prepared for the new anti-corrosion coating.
Depending on the condition, the following steps are taken:
Simply painting over it will not reliably stop corrosion if loose rust or moisture remains trapped under the coating.
Weathering steel can generally be welded. However, the process and the welding filler material must be suitable for the material used and the load on the component.
For load-bearing areas, repairs must not be based on visual criteria alone. This applies in particular to corner posts, frames, cross members, and areas around the corner castings.
If the container is to continue being used for transport, a professional inspection and CSC recertification may be necessary.
Yes. The robust steel construction provides a solid foundation for custom conversions. Doors, windows, ventilation, and technical connections can be integrated into the container shell.
However, cutouts alter the structural load distribution of the steel frame. Larger openings must therefore often be reinforced with additional steel profiles.
Corrosion protection, drainage, and potential thermal bridges should also be considered from the start. m³ plans container conversions to suit their intended use and the requirements for transport and installation.
Yes. Shipping containers are manufactured from robust Corten steel . The material is designed to withstand the heavy demands of international transport and protects the structure against atmospheric corrosion better than standard structural steel.
Yes. When uncoated Corten steel is exposed to moisture and oxygen, its surface begins to oxidize. Under the right conditions, this can form a dense patina that slows down further corrosion. For painted shipping containers, however, any visible rust should be inspected and the damaged coating repaired professionally.
Shipping containers are typically painted to provide additional protection for the steel. Damaged areas of paint should be repaired professionally.
Yes. Constant exposure to moisture, salt, chemicals, or a lack of drying periods can lead to progressive corrosion and, eventually, material loss.
Light surface rust does not automatically impair functionality. However, deep corrosion, holes, or weakened structural components must be inspected more closely.
Yes. The welding process and filler material must be compatible with the existing steel. Repairs to load-bearing areas should be carried out by a specialist company.