How Many Sinks Fit a 20ft or 40ft Container? Loading Math
Quick answer
There is no fixed number of sinks per container — the count comes from one formula: usable container volume ÷ packed carton volume, adjusted for how the order mixes models and accessories. Below is the standard method and a worked example with clearly stated assumptions, so you can sanity-check any loading plan a factory sends you.
Container interiors (standard dry vans)
| Container | Interior (m) | Nominal volume | Practical capacity* |
|---|---|---|---|
| 20 GP | 5.90 × 2.35 × 2.39 | ≈33.2 CBM | ≈28 CBM |
| 40 GP | 12.03 × 2.35 × 2.39 | ≈67.7 CBM | ≈60 CBM |
| 40 HQ | 12.03 × 2.35 × 2.69 | ≈76.4 CBM | ≈68 CBM |
*Practical capacity is lower than nominal because cartons do not tessellate perfectly, door clearance is lost, and dunnage takes space. Exact interiors vary slightly by carrier and container age.
Worked example (assumptions stated)
Take a 780 × 500 mm single-bowl workstation, packed at an assumed carton size of 0.82 × 0.56 × 0.36 m = 0.165 CBM, loose-loaded (not palletized), accessories boxed inside the sink carton:
- 40 HQ: 68 ÷ 0.165 ≈ 412 cartons
- 40 GP: 60 ÷ 0.165 ≈ 363 cartons
- 20 GP: 28 ÷ 0.165 ≈ 169 cartons
Change any assumption and the number moves: palletized loading typically costs 10–15% of capacity; a mixed order of 5 models with different carton footprints loses another 5–10% to fit; separate accessory cartons add volume but improve stacking safety. Treat any factory quote of a round number — “500 pcs per 40HQ” — as a claim to verify with real carton dimensions, not a promise.
Five factors that change a real loading plan
1. Carton design
Sink cartons nest well because the bowl is hollow, but edge protection (foam corners, edge boards) adds bulk. Stronger cartons stack higher and save dunnage — worth the extra cents.
2. Mixed models
An order of one model loads at the theoretical maximum. Real orders mix lengths (550–1800 mm across our range), and the last pallet-space of a long model rarely fills with a short model.
3. Pallets or loose
Pallets protect and speed handling; they cost volume. Retail-bound orders usually palletize; distributor restock usually loose-loads.
4. Moisture control
Stainless sinks arrive spotless and can arrive stained if container rain and paper packaging meet. Container desiccants and a dried, vented load matter on long routes.
5. Stack order and FIFO
Heavy double-bowl cartons below, art basins and accessories above — and the SKUs to be unpacked first loaded last.
How we handle it
Carton dimensions are fixed at order stage, per model, before the PI is signed — so the loading plan you approve is calculated from real boxes, not estimates. Send your model list and destination port and you will get a per-container count and a mixed-load layout. If you are comparing factories, ask each of them for the same thing; a factory that cannot produce carton dimensions per model is guessing at your freight bill. For model dimensions, start with the dimension table and the specification guide; for sourcing context, see sourcing stainless steel sinks from China and custom sink sizes for cabinet manufacturers.