China sets records with new self-unloading vessel

China State Shipbuilding Corp, the world's largest listed shipbuilder in terms of production capacity, delivered on Tuesday a self-unloading bulk carrier custom-built for a landmark project off the coast of Guinea in West Africa, noting that the vessel sets several records in its class.

The Wontanara, built by CSSC Chengxi Shipyard for global mining giant Rio Tinto and boasting a cargo capacity of 41,800 metric tons, has achieved three industrial milestones. It is the world's largest deadweight shallow-water transshipment self-unloader, the fastest self-unloading vessel ever made and the world's first self-unloader with bidirectional sailing capability in its tonnage class.

A self-unloader — also known as a self-discharger — is a ship capable of unloading its cargo using onboard equipment, without relying on shore-based cranes, mechanical grabs or conveyor systems.

The Wontanara, which was delivered at the shipyard's Yangzhou facility in Jiangsu province, measures 215 meters in length, 42 meters in beam width and 14.5 meters in molded depth, and has a cargo hold capacity of 29,000 cubic meters.

The vessel, powered by a full diesel-electric propulsion system, completed a 12-day trial in the East China Sea between late June and early July.

The CSSC said in a statement that the ship's delivery marks a major step in China's transition from a follower to a global leader in the high-end self-unloading transshipment vessel sector.

Zhang Xinlong, general manager of CSSC Chengxi Shipyard, said that Rio Tinto has ordered five such self-dischargers, with the Wontanara being the first. "The vessel's construction started in May last year, and the 14-month delivery cycle has underscored Chengxi's robust research and manufacturing strength," he said, noting that the model features a high level of automation with a small crew. "For example, steering maneuvers can be executed by a single operator using several control levers."

The second self-discharger is expected to be delivered in October, and all five are scheduled for handover by next summer, Zhang added.

The five vessels will operate off the coast of Guinea, serving as the main transshipment equipment for the Simandou iron ore project. They will shuttle ore from shallow-water terminals to large ocean-going bulk carriers anchored in deep waters.

Jiang Minghua, chief designer of the Wontanara, said it is equipped with two independent lifting systems with a combined unloading rate of 12,000 tons per hour.

Before its debut, the world's fastest self-discharger — a vessel converted by CSSC Chengxi Shipyard — had an unloading capacity of about 7,000 tons per hour.

According to Jiang, 41,800 tons of iron ore would fill almost 700 standard railway freight cars, stretching more than 7 kilometers, and yet, the vessel can unload a full cargo in under 3.5 hours.

"Working in rotation, the five ships can complete full transshipment and loading for a 200,000-ton ocean-going bulk carrier within 24 hours, minimizing anchorage time for large transportation vessels and effectively increasing mine output," he said.

To date, the shipyard has repaired, converted and built nearly 100 self-dischargers, giving it the world's most comprehensive product portfolio and the largest global market share in the sector.