Introduction
In the world of international logistics, not all cargo fits easily into a standard container. That’s where flat rack containers come in. They are designed to handle oversized, heavy, or oddly shaped goods, flat racks provide unmatched flexibility for shippers dealing with cargo that cannot be accommodated in standard enclosed containers. From heavy machinery to structural components, flat rack containers play an important role in global shipping.
In this post, we’ll explore the purpose of flat rack containers, examine the types of commodities they are commonly used for, and review a real-life case study that demonstrates their utility.
What Is a Flat Rack Container?
A flat rack container is a specialized shipping container with no side and top walls with either fixed or collapsible end walls. This design enables it to carry goods that exceed the dimensions of standard containers, especially in width or height. Flat racks are particularly well-suited for good that must be loaded from the top or sides using cranes or forklifts.
Flat racks are typically available in two sizes:
- 20-foot flat rack: Ideal for smaller, yet heavy or awkward cargo.
- 40-foot flat rack: Suitable for larger, more cumbersome equipment or machinery.
Some flat racks also come with lashing rings and supports for better securing cargo during transit, especially on ocean vessels where movement from waves is a concern.
What Is OOG (Out-of-Gauge) Cargo?
Out-of-Gauge (OOG) cargo refers to freight that exceeds the internal dimensions of a standard shipping container. This includes:
- Over-width cargo: wider than 8′ (2.44m)
- Over-height cargo: taller than 8’6″ (2.59m)
- Over-length cargo: longer than 20’ or 40’, requiring special bracing or multiple containers
Because of its irregular dimensions, OOG cargo often can’t be containerized in traditional dry or high-cube containers. That’s where flat racks step in.
Flat rack containers are specifically designed to handle OOG cargo. They offer:
- Open loading space for oversized dimensions
- Heavy-duty flooring to support weight-intensive freight
- Multiple lashing points to secure cargo during transit
- Stacking capabilities when not in use, aiding in repositioning logistics
OOG shipments typically require additional planning, including route surveys, port approvals, and specialized handling—areas where experienced freight forwarders make a difference.
Primary Uses and Commodities Shipped on Flat Rack Containers
Flat rack containers are most often used for out-of-gauge (OOG) cargo. The types of commodities commonly shipped on flat racks include:
- Heavy Machinery
Industrial equipment such as excavators, bulldozers, cranes, and pavers are commonly shipped on flat racks due to their size and weight. These machines often exceed height or width restrictions for enclosed containers.
- Construction Materials
Prefabricated walls, scaffolding, cement mixers, and other materials used in construction projects are often moved on flat racks, especially for large-scale building projects overseas.
- Industrial Components
Items like steel beams, generators, transformers, wind turbine parts, and pipe segments are typical flat rack cargo. These pieces often exceed length or width constraints.
- Vehicles and Boats
Flat racks are used to transport oversized trucks, buses, RVs, and even small yachts or boats that cannot fit into high cube or standard containers.
- Military or Government Equipment
Military bases frequently require the movement of vehicles, shelters, or field machinery, all of which are typically handled with flat racks due to their robust build and accessibility.
Case Study: Shipping Trailers from the USA to Europe
Project Overview:
A U.S.-based heavy equipment manufacturer needed to ship three support trailers to a military base in Luxembourg. The dimensions of the units exceeded only the width limits of a standard container.
Solution:
We utilized a 40-foot flat rack container to accommodate this cargo. We first picked up the units on a flatbed from the shipper in west Texas. Then, we delivered them to the port of Houston where the trailers were towed onto the container and secured using heavy-duty chains and lashing equipment. Additionally, we tarped the cargo to ensure that it was protected while in transit. It was treated as an OOG shipment and required special handling at the port.
Key Challenges:
- Coordination with the port authority for lift-on/lift-off (LOLO) crane services
- Adjusting to the inclement winter weather.
- Ensuring the trailers were properly protected against saltwater corrosion
Outcome:
The shipment arrived at the port of Antwerp within 30 days from the pickup in Texas. Upon arrival in Belgium, the container was brought to a local warehouse outside Antwerp where the goods were safely unloaded and then transloaded onto a flatbed trailer for delivery to the end user in Luxembourg. The flat rack container allowed the client to receive the units without having to dismantle them, saving significant time and labor on both ends.
Flat rack container shipment from USA to Luxembourg.
Advantages of Using Flat Rack Containers
- Versatility: Able to accommodate wide, tall, or heavy cargo.
- Easy Loading/Unloading: Open sides make it ideal for top or side loading.
- Secure Transport: Fitted with lashing rings and supports for tight securing.
- Time-Saving: Reduces or eliminates the need for disassembly/reassembly of equipment or structures.
Key Considerations When Shipping with Flat Racks
While flat racks offer many benefits, there are some challenges and requirements to keep in mind:
- Cost: OOG and flat rack cargo often incur additional port handling and freight charges.
- Space Availability: Flat racks are less common than standard containers; early booking is recommended.
- Regulations: Ports and carriers have strict requirements for weight distribution, overhangs, and cargo securing.
- Insurance: Heavier cargo or expensive machinery should be properly insured due to exposure to weather and port handling risks.
Why Flat Rack Shipping Requires the Right Partner
Flat rack container shipments are often of high-value, high-risk, and time-sensitive. When dealing with OOG cargo, the margin for error is small. Poor securing, incorrect routing, or mismanaged customs documentation can result in serious delays, damage, or fines.
That’s why businesses across numerous industries—from construction and energy to government and manufacturing—choose logistics partners with deep experience in specialized freight.
An expert freight forwarder like Allison Shipping not only arranges the equipment, but also:
- Analyzes and classifies cargo dimensions for OOG requirements
- Identifies the safest, most efficient vessel routing options
- Provides on-site assistance for loading and lashing
- Manages export/import documentation and compliance
- Offers cargo insurance and condition reports
These added layers of service don’t just protect your cargo, they protect your timeline, your reputation, and your bottom line.
Ready to Ship Smart?
Flat rack containers are essential tools in the world of international shipping. For businesses moving oversized, awkward, or heavy cargo, flat racks provide the ideal solution that balances flexibility, safety, and cost-efficiency. Whether shipping excavators across oceans or delivering wind turbines to job sites, flat racks are a key enabler of global commerce.
If you’re preparing to move an oversized load, planning a construction project abroad, or need help navigating complex OOG cargo requirements, don’t go about it alone. Flat rack shipping demands precision—and that’s where experience pays off.
Let our team at Allison Shipping help you find the right solution, minimize risk, and keep your cargo moving forward. Your shipment deserves more than a container—it deserves a strategy. Contact us today for a custom quote and logistics plan that fits your needs.
Interested in shipping your OOG cargo internationally? Get Pricing on your next shipment today.
