How Many Tons of Steel Coil Fit in a 20GP, 40GP or 40HQ Container?
How Many Tons of Steel Coil Fit in a 20GP, 40GP or 40HQ Container?
Direct answer: steel coil is weight-limited, not volume-limited. A 20GP is normally loaded with roughly 20-25 tonnes, and a 40GP or 40HQ rarely does better because the box payload ceiling is similar and destination road-axle limits often bind before the container does. The practical figure is always confirmed at booking, against the carrier's payload and the importing country's road weight rules.
| Container | Internal volume | Box payload limit | Practical coil load |
|---|---|---|---|
| 20GP | about 33 m3 | about 28 t | 20-25 t |
| 40GP | about 67 m3 | about 26-28 t | 20-25 t |
| 40HQ | about 76 m3 | about 26-28 t | 20-24 t |
Why the 40-foot box does not double your tonnage
A 40-foot container has roughly twice the volume of a 20GP but almost the same payload limit, because the extra steel in the longer box is spent on the box itself. For dense cargo such as coil, that extra volume buys nothing: a coil load typically fills only a third to a half of the internal space before the weight ceiling arrives.
This is why coil buyers so often ship in 20GP units. Two 20-foot boxes usually move more tonnes, and unload more conveniently, than one 40-foot box - and they isolate damage or moisture problems to half the cargo.
What really sets the number
Four constraints decide the final figure, and the lowest one wins: the container's maximum gross weight, the carrier's declared payload, the road axle limit in the importing country, and the physical fit of coil diameter against internal width and height.
Road limits are the constraint buyers most often miss. A box that is legal at the port can be overloaded on the truck that leaves it.
How to get an exact figure
Give the coil OD, ID, width and unit weight, plus the destination country, and the loading plan can be calculated rather than estimated - including how many coils per box and whether the stack needs a second tier.
