Recently, Shanghai Chengxi Shipbuilding Co., Ltd. successfully delivered the 74,000-ton self-unloading ship “Agsey,†which was modified by the Canadian Steamship Company (CSL). This project marked a significant milestone for Chengxi Shipyard, showcasing its technical expertise and strengthening the long-term partnership with CSL.
The Agsey was originally named "Nayong," a single-hull tanker that had been in service for over two decades. With the International Maritime Organization’s ban on single-hull tankers transporting heavy oils like crude oil and fuel oil starting in April 2005, CSL decided to upgrade the vessel. They chose to convert it into a self-unloading bulk carrier, a complex and challenging task that required top-tier shipbuilding capabilities.
Two years prior, CSL had already worked with Chengxi Shipyard on the successful modification of the “Oriental†self-unloading vessel. The positive experience left a strong impression on the shipowner, who later reached out to Chengxi again for the “Nayong†project. This collaboration was not only a testament to Chengxi’s reputation but also an opportunity to prove itself in a technically demanding field.
Modifying a large self-unloading bulk carrier was no easy feat. There were no prior examples to follow, and the engineering challenges were immense. The complexity of the design, the difficulty of construction, and the high risk involved made this one of the most ambitious projects in the industry.
During the modification process, Chengxi faced several major obstacles. First, launching the new sections onto the slipway posed a significant challenge due to their massive weight—around 11,000 tons. To address this, the shipyard adopted a unique ship-to-drain approach, which had never been used before in China. Engineers conducted extensive calculations and experiments to ensure safety and success.
Next, docking the new section in the floating dock was another critical step. The old and new segments together exceeded 200 meters in length, requiring precise alignment in a tight space. Any misalignment could lead to structural issues and weaken the welds. To prevent this, the team focused on quality control, minimizing gaps and reducing the number of seams. They also reinforced the dock with custom supports and docking devices to handle the heavy load.
Finally, installing the self-unloading system presented another hurdle. The ship’s large cargo hold featured a funnel-like structure with a very tight clearance requirement—no more than 3 mm between the doors. Ensuring the conveyor belt’s precision and resolving equipment issues required close coordination between the shipyard, the client, and the suppliers.
To complete the project, Chengxi mobilized a large team of skilled workers. Every detail was carefully managed, from production planning to quality control. Employees worked around the clock, even sacrificing time with family during holidays, to meet deadlines and maintain high standards.
The success of the “Agsey†project earned Chengxi Shipyard widespread recognition. Before the ship was even delivered, CSL signed a second contract for another 74,000-ton conversion and entrusted Chengxi with the repairs of six additional self-unloading vessels. This achievement not only highlighted Chengxi’s capabilities but also solidified its position as a trusted partner in the global shipping industry.
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