Bulk carriers have generally maintained strong growth since their emergence in the mid-1950s. In the international maritime industry, bulk carrier transportation accounts for more than 30% of cargo transportation. Due to factors such as large freight volume, sufficient supply, fixed routes, and high loading and unloading efficiency, bulk carrier transportation can achieve good economic benefits, and bulk carriers have become the main force of transport ships. With the development of the world economy, bulk carrier transportation will maintain a growth momentum.

Before the 1950s, there were no special bulk carriers, and the bulk carriers in Shanghai International Logistics were all transported by ordinary general cargo ships. Bulk goods such as grain and cement are less mobile than liquids. Therefore, when loading these bulk cargoes, there is still a chess-shaped gap under the deck around the hatch after the wrench around the hatch is full. After the vessel rolls laterally at sea, the bulk cargo flows towards neutral, creating a free surface that spans the entire width of the vessel. When there is lateral roll, the bulk cargo will flow to one side and the vessel will immediately pitch laterally, which can easily capsize in a storm.

In order to solve this safety problem, the widely used special bulk carrier structure type has been gradually formed: bottom tanks are arranged on both sides, hatch coamings are added to ensure full tanks, bottom tanks are arranged on both sides for easy cleaning, double bottom And four side tank areas adopt longitudinal frame structure to ensure the overall longitudinal strength of the hull. The total longitudinal bending stress near the waterline of the side tanks on both sides is very small, and the transverse skeleton structure with relatively simple structure is adopted: the deck between the two hatches is not involved to ensure the total longitudinal strength. The emergence of special bulk carriers can better solve the problem of bulk cargo flow, improve the safety of bulk cargo transportation, and make marine bulk carrier transportation enter a new stage of development.