Resource Transport
Bulkships transport huge volumes of cargoes such as iron ore, coal, grain, salt, aluminum, and copper ore without packing or packaging. These vessels are called “bulkers,” “dry bulkers,” or “bulk carriers,” and as the names imply, transport dry cargo in bulk. Bulkships vary widely in size and configuration, depending on the cargo they carry and the characteristics of the ports where they call.
Bulkships by Size

VLOC stands for Very Large Ore Carrier. This class of ship is a recent development, reflecting the trend toward larger vessels in pursuit of economy.
The “Capesize” is the largest class of bulkship that can carry any type of cargo, such as iron ore, coal, and grain. They are called “Capesize” ships because they cannot pass through the Panama Canal and have to sail around the Cape of Good Hope to sail between the Pacific and Atlantic oceans.
The “Panamax” is the largest class of vessel that can pass through Panama Canal, measuring 900 feet (about 274m) long with a breadth of up to 106 feet (about 32m). The name Panamax can also apply to other types of vessels, such as containerships, car carriers, and cruise ships.
The word “handy” is included in the names of ship types smaller than Panamax. This reflects the convenience of being able to call at most ports around the world. Handy bulkers are equipped with their own cranes, allowing them to load and discharge cargo even at ports without loading/discharging facilities, and can transport a wide variety of commodities.

Bulkship Names by Size
  Standard
deadweight tonnage
Main cargoes
Very Large Ore Carrier (VLOC) 250,000 iron ore
Capesize 180,000 iron ore, coking coal
Panamax 82,000 Iron ore, coking coal,
thermal coal, grain
Handymax 58,000 Thermal coal, grain, salt, cement, steel
Small Handy 28,000 Steel, cement, grain, ore

Structure/Characteristics
Bulkships have “topside tanks,” triangular ballast tanks (filled with water to stabilize the vessel) fitted at both shoulders/wings of the cargo holds. These help the ship maintain the proper trim no matter how much cargo is on board. The sides on the lower part of the hold are designed with a hopper configuration to maximize loading/discharging efficiency by preventing cargo from accumulating in the corners. Some bulkers have cranes for loading/discharging, while others rely on shoreside equipment. In general, the vessels larger than Panamax do not have cranes. There are hatch covers at the top of the hold, which are opened only during loading/discharging.


Dedicated Bulkships by Cargo

Generally, an optimal ship type of bulkship is chosen based on cargo volume and port scale, facilities, and equipment. But some dedicated bulkships are designed and constructed to transport a specific cargo in the safest, most economical, and most efficient manner.


Iron ore has a high specific gravity, so the cargo hold is designed to be narrow, with the cargo heaping up in the center. Capesize-class vessels without cranes represent the mainstream in economical, efficient transport of iron ore.



These vessels transport coal for thermal power generation. They are designed to match the water depth and discharging equipment at a dedicated berth for a power station. The wide-breadth type (80,000-90,000DWT) is the mainstream, as this configuration allows the ship to load a large volume of coal and still navigate safely in shallow waters.



This type of vessel is specially designed to carry woodchips, the raw material for paper. The specific gravity of woodchips is low, so the hold is designed to maximize cargo capacity. In addition, wood chips do not shift very much in transit, eliminating the need for topside tanks.



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