A rather unique heavyweight vessel docked at Niutou Island Immersed-Tube Prefabrication Factory in Zhuhai waters on April 27 to carry the first tube of the Shenzhen-Zhongshan Corridor sea channel.

Yihang Jin'an 1 was built in China in 2019 especially for the Shenzhen-Zhongshan Corridor project. It is the world's first self-propelled vessel designed for dynamic positioning and tracking of immersed tubes. Using an immersion gesture control system, it can immerse a tube 50 m (55 yd) under water and abut it precisely.

Yihang Jin'an 1 arrives at deep basin area of Niutou Island [Photo by Lu Zhihua / Guanhai App]

By May, the first immersed tube of the sea channel will be connected to the vessel at the deep basin area for a second fitting-out, immersion trials, and a departure drill. The vessel's installation system will also be debugged, according to Yue Yuanzheng, deputy general manager of the Shenzhen-Zhongshan Corridor project of CCCC First Harbor Engineering.

The immersed tube will be shipped from Niutou Island to the installation site 50 km (31 miles) away and be immersed by late June. For safety reasons, 21 km (13 miles) of shipping lanes will be restricted. Yihang Jin'an 1, however, reduces the impact on other vessels by cutting transport time from 24-26 to 12-13 hours.

Yihang Jin'an 1 was designed by Shanghai Zhenhua Heavy Industries and constructed by CSSC Huangpu Wenchong Shipbuilding under the proposal of CCCC First Harbor Engineering. It has fully independent and domestically patented intellectual property rights and is in application for international IPR protection.