Bulk carrier.

A bulk carrier moves unpackaged dry cargo such as ore, coal, grain and cement in large holds under hatch covers. Shippers meet it whenever a cargo is sold by the tonne and fills a whole hold or a whole ship, from 500 t river lots to 400,000 DWT ore cargoes.

Dry cargoDWT

Bulk carrier at sea — Photo: Nsandel, Public domain, Wikimedia Commons

Navo drawing, schematic, not to scale

Single-deck ship with large hatches for unpackaged dry cargo in volume. Small classes are geared, Capesize and larger need shore loaders. The largest ore carriers reach 400,000 DWT.

What a bulk carrier is

A bulk carrier, or bulker, is a merchant ship built to carry unpackaged bulk cargo in its holds: typically grain, coal, ore, forest products, steel coils or cement. Bulk carriers make up 21 percent of the world's merchant fleets.

They range from single-hold mini-bulk carriers to ore ships of 400,000 DWT. South Korea is the largest single builder, and 82 percent of these ships were built in Asia. Crews range from three people on the smallest ships to over 30 on the largest.

How cargo is loaded and discharged

Every bulk carrier has a series of holds under prominent hatch covers. Geared ships carry cranes, derricks or conveyors and can work ports without shore equipment. Gearless ships depend on shore loaders and unloaders, which saves the cost of installing and maintaining cranes.

Conveyor belts load at standard rates of 100 to 700 tons per hour, and the most advanced ports reach 16,000 tons per hour. A crane's discharge rate is limited by its grab, which holds 6 to 40 tons. Self-dischargers use their own conveyor belts or an excavator running over the hatches to unload quickly.

Size classes and dimensions

Bulk carriers fall into six size categories: small, Handysize, Handymax, Panamax, Capesize and very large. Typical ranges are 10,000 to 35,000 DWT for Handysize, 35,000 to 59,000 DWT for Handymax, 60,000 to 80,000 DWT for Panamax and 80,000 DWT and over for Capesize. Very large ore carriers start above 200,000 DWT.

Handymax ships are typically 150 to 200 m long with five holds and four cranes. Panamax size follows the old canal locks: 32.31 m beam, 294.13 m length and 12.04 m draft. Port limits create regional classes such as Kamsarmax (229 m), Newcastlemax (about 185,000 DWT) and Seawaymax (226 m, 7.92 m draft).

Cargo and trades

Handysize and Handymax ships are general purpose and together make up 71% of bulk carriers over 10,000 DWT. They carry grain, fertiliser, cement, steel coils and forest products, often into ports with limited equipment.

Capesize ships are specialised: 93% of their cargo is iron ore and coal. They are too large for the Panama Canal, but the deepening of the Suez Canal to 20 m lets most of them pass. Mini-bulk carriers of 500 to 2,500 tons serve rivers and pass under bridges.

Variants and recent developments

Besides geared, gearless and self-discharging ships, there are combined carriers for liquid and dry bulk, common in the 1970s but rare since 1990, and Great Lakes freighters with a forward house for transiting locks.

In October 2022, the MOL bulk carrier Shofu Maru arrived in Newcastle on its maiden voyage as the first bulk carrier partly powered by a hard sail, with a five percent fuel saving expected. Larger bulkers from Handymax up usually run a single low-speed two-stroke diesel.

What to know when booking

Bulk freight is usually quoted per tonne on a voyage basis, but some shippers charter a whole ship and pay a daily rate instead. Match the size class to your lot and to the draft and length limits of both ports.

Ask whether the ship is geared if the discharge port lacks shore cranes, and check the port's loading rate, since it decides how long the ship stays alongside. A mini-bulk carrier spends about 55 hours in port per call, so handling speed counts on short trades.

Variants

Geared bulk carrierHandysize to Handymax ship with its own cranes, derricks or conveyors for ports without shore gear.

Gearless bulk carrierShip of any size that relies on shore loaders and unloaders, including the largest ore carriers.

Self-dischargerBulker with conveyor belts or a travelling excavator that unloads its own cargo quickly.

Combined carrierShip built for both liquid and dry bulk, kept in separate holds and tanks.

LakerGreat Lakes bulk carrier with a forward house that helps it transit locks.

Mini-bulk carrierSingle-hold river ship carrying 500 to 2,500 tons with a crew of three to eight.

Size classes

Handysize10,000 to 35,000 DWT. Typical modern ship: about 32,000 DWT, 10 m draft, 5 holds, four 30 t cranes

Handymax35,000 to 59,000 DWT (bulk carrier table); 40,000 to 50,000 DWT (Handymax article). Typically 150 to 200 m long

Supramax50,000 to 60,000 DWT. Five holds, four cranes of about 30 t

Ultramax60,000 to 69,999 DWT. Indicative band (Drewry, used by USDA since April 2020): a larger Supramax

Panamax60,000 to 80,000 DWT

KamsarmaxLOA 229 m max. Port Kamsar berth length

Post-Panamax / Kamsarmax79,000 to 99,999 DWT. Indicative band (Drewry, used by USDA)

Capesize80,000 DWT and over (bulk carrier table); about 170,000 DWT typical. About 290 m long, 45 m beam, 18 m draught

VLOC / VLBCover 200,000 DWT. Very large ore and bulk carriers, a subset of Capesize

Valemax380,000 to 400,000 DWT. 360 to 362 m long, about 65 m beam, 22 to 23 m laden draught

All size classes and canal limits

Questions shippers ask

Which bulk carrier size fits my cargo?

Lots up to about 35,000 t suit Handysize, 35,000 to 59,000 t Handymax, 60,000 to 80,000 t Panamax, and larger ore or coal lots Capesize. Port draft and length limits also decide.

Do bulk carriers have their own cranes?

Smaller Handysize and Handymax ships are often geared. Capesize and larger ships are gearless and need shore loaders.

How fast is a bulk carrier loaded?

Standard conveyor rates are 100 to 700 tons per hour, and the best terminals reach 16,000 tons per hour. Grab discharge depends on bucket size, 6 to 40 tons.

Can I hire a whole bulk carrier?

Yes. Some shippers charter a ship and pay a daily rate instead of a price per ton.