How many tonnes of ferrosilicon fit in a container?
Payload, bulk density and bag size decide the answer. A worked example for a 20GP, plus the products where volume runs out before weight.
The quick answer for ferrosilicon in a 20GP is usually 25–28 tonnes, limited by payload rather than volume. But that answer changes with the product, the bag and the container — and getting it wrong is expensive at the port.
KRIS ships bagged ferroalloys in 20GP and 40HQ containers and photographs every loading before the doors close. If you are combining grades, send the list and we will return a loading plan with the container count and the limiting factor.
Request a quote →Weight usually runs out before volume
A 20GP has about 33 m³ of internal volume and a payload around 28 tonnes. Ferrosilicon has a bulk density near 2.2 t/m³, so a full container by volume would weigh over 60 tonnes. Payload is the binding constraint.
| Container | Internal volume | Typical payload |
|---|---|---|
| 20GP | ~33 m³ | ~28 t |
| 40GP | ~67 m³ | ~26.5 t |
| 40HQ | ~76 m³ | ~26 t |
Worked example: FeSi 75 in a 20GP
Take 25 kg bags, a bulk density of 2.2 t/m³ and 85% fill efficiency. Volume capacity is roughly 33 × 0.85 × 2.2 = 61.7 tonnes, so the 28-tonne payload governs. At 25 kg per bag, that is 1,120 bags — before pallets, dunnage and weight limits on local roads.
In practice we quote 25–27 tonnes per 20GP for bagged ferrosilicon, depending on the destination’s road limits and whether pallets are used.
When volume becomes the constraint
Light materials behave differently. Coke particles at roughly 0.55 t/m³ fill a 20GP by volume at about 15 tonnes, well before the payload limit. Carburizer and some briquettes sit in between. This is why a single “tonnes per container” number is misleading across a product range.
Mixed containers
Combining two or three grades in one container is normal, but the loading plan has to respect axle limits, bag stacking height and the order of discharge. Send us the grades and tonnages and we will return a loading plan with the container count and the limiting factor.
FAQ
Can a 40HQ carry more ferrosilicon than a 20GP?
Not by weight. A 40HQ has a lower payload than a 20GP on many trade lanes, although it has more volume. For dense alloys, two 20GP containers often carry more than one 40HQ.
Do pallets reduce the load?
Yes. Pallets add height and weight, and usually cut the usable payload by 5–10%. Confirm the destination’s handling requirements before choosing palletised bags.
This note is general information for buyers. It is not trading, financial or investment advice. Specifications must be confirmed against the COA for each lot.