Freight equipment

Flat rack container

A flat rack is a container reduced to its floor and, usually, two end walls. It carries cargo that will not fit inside any box, and the cargo becomes part of the securing problem.

Mode: Ocean
Published figures: 11, each with a named publisher

Shipping containers stacked in rows across a port container park, seen from above.

What is left when the sides come off

A flat rack has a reinforced floor, corner castings so it can be handled and stowed like a container, and end walls that on many types fold flat when the unit is empty. There are no sides and no roof.

The point is that the cargo may be wider than a container, taller than one, or both. A flat rack gives it a floor that the terminal's equipment already knows how to lift, without pretending to enclose it.

Out-of-gauge is a commercial fact, not a technical one

Once cargo extends beyond the flat rack's own footprint, it occupies space that would otherwise have carried other containers — beside it, above it, or both. Carriers price that lost slot capacity, and the charge follows the dimensions rather than the weight.

The consequence is that a few centimetres can change the cost of a shipment sharply, because they change how many slots the piece blocks. Measuring the cargo accurately at the widest and highest points, including any packaging, cradle or protruding fitting, is the single most useful thing a shipper can do before asking for a price.

Securing an unenclosed piece for a sea passage

A vessel moves in every axis for days at a time. Cargo on a flat rack is held only by what secures it to the deck, so lashing is engineered for the piece: rated points, angles chosen so the restraint acts against the direction of movement, and bearing timbers or a cradle spreading the load across the floor rather than concentrating it.

Heavy or unusual pieces frequently need a securing arrangement drawn up and approved before loading. That is a specialist exercise and belongs with the parties doing the stowage, not with a general packing instruction.

Full exposure, for the whole voyage

There is no roof, no side and, at sea, no shelter. Cargo on a flat rack takes weather and salt spray for the entire passage, and anything vulnerable to either needs its own protective wrapping or coating specified as part of the packing.

Rated payloads for flat racks vary widely between publishers — more than for any other container type — so the capacity that matters is the one stamped on the unit supplied, not a general figure.

Suited to

What this equipment is for.

Machinery, vehicles and plant that exceed a container's internal dimensions
Long items such as pipe, beams and fabricated steel
Cargo needing crane loading from above or from the side
Pieces whose shape makes any enclosed unit impossible

Specifications

Published figures, and who publishes them.

These are not industry constants. Each figure below is one named publisher’s statement about its own equipment on the date it was checked, and where publishers disagree the row says so. For a specific shipment, the specification that matters is the one for the actual vehicle or container being used.

20ft

Internal dimensions: 5,638 length min. x 2,438 width at floor x 2,233 height; minimum width between posts 2,194; bottom height 370 (Hapag-Lloyd) mmFlat racks are dimensioned differently from box containers and the two publishers do not even use the same reference points, so the figures are not directly comparable. Hapag-Lloyd gives a five-value set (length min., width at floor, width min., height, height bottom). ONE gives 5,568 mm between corner posts x 2,194 mm between side rails x 2,213 mm. The one figure both agree on exactly is the 2,194 mm minimum width between posts, which is the binding constraint for most cargo and is the safest single number to publish. Loading length differs by 70 mm depending on where it is measured from.Hapag-Lloyd — source, checked 2026-08-14
External dimensions: 6,058 x 2,438 x 2,591 (L x W x H) mmONE is the only source fetched that publishes this. Identical to the 20ft dry external envelope from CIMC. The external envelope is what the ship cell and the trailer accept; cargo overhanging it becomes out-of-gauge and is priced and routed differently, which is the operationally relevant point.Ocean Network Express — source, checked 2026-08-14
Tare weight: 2,900-3,100 (Hapag-Lloyd 2,900; ONE special-cargo page 3,050; ONE dry-containers page 3,100) kg200 kg spread, and ONE again publishes two different values on two of its own pages (3,100 and 3,050 kg).Hapag-Lloyd (low endpoint); high endpoint Ocean Network Express at https://www.one-line.com/en/dry-containers — source, checked 2026-08-14
Maximum gross weight: 34,000 to 45,000 (ONE special-cargo page 34,000; ONE dry-containers page 38,100; Hapag-Lloyd 45,000) kgThe worst variation in the entire dataset: three different ratings spanning 11,000 kg, or 32%, and two of the three come from the same carrier's own website. All three reconcile internally against their own tare and payload rows, so none is a typo — they are genuinely different equipment ratings. A single published figure here would be wrong for most of the market and could materially mislead a shipper planning a heavy lift. Publish the range with all three named, or publish nothing.Hapag-Lloyd (45,000); the 38,100 and 34,000 figures are both Ocean Network Express, at https://www.one-line.com/en/dry-containers and https://www.one-line.com/en/special-cargo/containers-and-specifications respectively — source, checked 2026-08-14
Payload: 30,950 to 42,100 (ONE special-cargo page 30,950; ONE dry-containers page 35,000; Hapag-Lloyd 42,100) kgAn 11,150 kg spread, roughly 36% — by far the widest disagreement found, and the strongest single argument in this dataset against publishing any figure as 'the' specification. The payload a flat rack can actually take also depends on load distribution and lashing, which no publisher reduces to one number.Hapag-Lloyd (42,100); the 35,000 and 30,950 figures are both Ocean Network Express — source, checked 2026-08-14
Cubic capacity: 28.4 m3Single-source only: Hapag-Lloyd publishes no capacity row at all for flat racks, which is itself informative — a flat rack has no enclosed volume, so a cubic capacity figure is a notional loading envelope rather than a container volume. Low confidence, and arguably should not be published for this equipment type at all.Ocean Network Express — source, checked 2026-08-14

40ft High Cube

Internal dimensions: 11,652 length min. x 2,347 width at floor x 2,265 height; minimum width between posts 2,245; bottom height 648 (Hapag-Lloyd) mmHapag-Lloyd labels this type '40' Flatrack High Cube / 40' Platform'. ONE's comparable 40/HC flat rack gives 11,658 x 2,374 x 2,264 mm; loading length agrees within 6 mm and height within 1 mm, but the width reference differs by 129 mm because the two measure to different points. ONE separately lists a standard-height 40ft flat rack (11,652 x 2,208 x 1,955 mm, 8'6") which is a different piece of equipment with a much lower loading height — do not merge the two.Hapag-Lloyd — source, checked 2026-08-14
External dimensions: 12,192 x 2,438 x 2,896 (L x W x H) mmONE is the only source fetched publishing this. ONE gives 12,192 x 2,438 x 2,591 mm for its standard-height 40ft flat rack — the 305 mm height difference is exactly what distinguishes the high cube frame.Ocean Network Express (40/HC Flat Rack Container) — source, checked 2026-08-14
Tare weight: 5,900-6,250 (Hapag-Lloyd 5,900; ONE special-cargo page 6,100; ONE dry-containers page 6,250) kg350 kg spread, and ONE once more gives two different values across its own two pages (6,250 and 6,100 kg).Hapag-Lloyd (low endpoint); high endpoint Ocean Network Express at https://www.one-line.com/en/dry-containers — source, checked 2026-08-14
Maximum gross weight: 55,000 (Hapag-Lloyd) or 58,600 (ONE) kg3,600 kg divergence. Hapag-Lloyd reconciles exactly (5,900 + 49,100 = 55,000); ONE's figures do not (6,250 + 52,500 = 58,750 against its stated 58,600, a 150 kg internal error on ONE's page), so slightly higher confidence in the Hapag-Lloyd figure.Hapag-Lloyd (55,000); ONE (58,600) at https://www.one-line.com/en/dry-containers — source, checked 2026-08-14
Payload: 49,100 (Hapag-Lloyd) to 52,500 (ONE) kg3,400 kg spread, about 7%. ONE's endpoint carries the 150 kg internal inconsistency noted above. As with the 20ft flat rack, achievable payload depends on load distribution and lashing and is not reducible to one number.Hapag-Lloyd (49,100); ONE (52,500) at https://www.one-line.com/en/dry-containers — source, checked 2026-08-14

Considerations

What constrains it.

Out-of-gauge charges follow dimensions, so measure at the widest and highest points including packaging
Lashing is engineered for the piece and may need approval before loading
Complete exposure to weather and salt spray for the whole voyage
Published payload ratings vary more than for any other container type

From equipment to load plan

Confirm the unit against the actual cargo.

Suitability depends on the goods, loading method and the specification of the equipment that will actually be used.

European road freight