Large machinery, boats or oversized pallets – when cargo does not fit into a standard container, the flat rack (FR) becomes the preferred solution. With a sturdy floor, two end walls (hinged or fixed) and no side walls, it is ideal for out-of-gauge shipments. Knowing the exact dimensions and weights saves time, money and hassle. This guide provides you with the most important data, practical tips and checklists.
Flat rack: overview of designs, uses and limitations
designs
Collapsible EndsFoldable front walls, space-saving when empty, versatile.
Fixed Ends: Fixed end walls often have a higher load capacity, but are less flexible for return transport.
40′ high cube flat rack: Higher construction (9′6″), specific to shipping companies, relevant for stowage heights and lashings.
Typical applications
Extra-wide machines
Excess height (e.g. generators)
Heavy goods with concentrated loads (e.g. construction machinery)
Rollable units (only with suitable lashing points)
Important: Load capacities vary depending on the shipping company and year of manufacture. For 20′ FRs, MGWs of up to 45,000 kg are common, and for 40′ FRs, up to 60,000 kg – the payload is always MGW minus tare weight.
Standardised external dimensions according to ISO
ISO 668 specifies the external dimensions of containers: 20′ or 40′ length, 8′ width, 8′6″ height. Flat racks follow these dimensions to ensure stackability and craneability. However, the internal dimensions vary depending on the end wall type and floor frame.
Typical flat rack dimensions and weights
Typical values (bandwidths per carrier):
20′ flat rack External dimensions: 6.058 × 2.438 × 2.591 m Internal dimensions: approx. 5.94 × 2.35 × 2.15–2.30 m MGW: up to 45,000 kg Tare weight: ~4.8–5.5 t Payload: ~30–40 tonnes
40′ flat rack External dimensions: 12,192 × 2,438 × 2,591 m Internal dimensions: approx. 11.7–12.0 × 2.35 × 1.95–2.30 m MGW: up to 60,000 kg Tare weight: ~5.5–6.5 t Payload: ~35–39 tonnes
Understanding MGW, tare weight, payload and ground load
MGW (Maximum Gross Weight): Maximum weight including tare
Tara: Net weight of the empty flat rack
Payload: MGW minus tare
Floor load/point load: Critical with concentrated loads – always distribute and secure
Tip: For point loads such as wheel loaders, use load distribution plates and secure the load in accordance with the CTU Code.
Create lashing plan with lashing equipment (SWL, LC)
Comply with CTU code + photo documentation
In the harbour:
Check gate-in time slot & equipment ID
Enter B/L data correctly
Note: Prices depend on the relationship, equipment, OOG dimensions and season – please request an individual quote for exact figures.
FAQ: Frequently asked questions
Which flat rack dimensions are binding? Only the data for the flat rack actually provided (equipment sheet) is binding. ISO 668 only defines the external dimensions.
How high can I build on a flat rack? Varies depending on route, header, CTU code and terminal conditions. Always check individually.
How much can a flat rack carry? 20 to 45 tonnes MGW, 40 to 60 tonnes MGW. The actual usable payload is usually 30–40 tonnes.
Why are point loads critical? Because they can cause local overloads. Distribute the load and secure it in accordance with the CTU Code.
Conclusion: Success with data, CTU code and the right setup
Flat rack shipping requires precise measurements, CTU code-compliant securing, correct documentation and early planning. With this knowledge, project cargo can be handled safely and efficiently.
Disclaimer: All information in this article has been carefully researched but is subject to change at any time. ODS Orient accepts no liability for the topicality, accuracy and completeness of the information provided.
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