On January 22, at the construction site on the Haimen side of the Haitai Yangtze River Tunnel—the underwater shield tunnel with the longest distance and largest cross-section in China—the cutterhead of the "Jianghai" shield machine, with the Zoomlion ZCC18000 crawler crane as the main lifting equipment and a 400-ton auxiliary crane working in coordination, completed an "aerial rotation" and then slowly descended to precisely dock with the main body of the launch shaft, successfully completing the task of lowering the cutterhead of the "Jianghai" shield machine into the shaft.

The "Jianghai" shield machine has an overall length of about 145 meters and a total weight of about 5,000 tons. Its cutterhead has a diameter of 16.64 meters and a total weight of about 460 tons, and is composed of 1 center block, 6 main cutter arms, and 6 auxiliary cutter arms. With such a massive body, assembling and operating it in the narrow underground space is imaginably difficult.

The process of lowering the cutterhead into the shaft is complex and requires close coordination between two crawler cranes. The Zoomlion ZCC18000 crawler crane first hoisted one end of the cutterhead, and the auxiliary crane helped raise the cutterhead; during lifting, the two cranes had to maintain a highly consistent height. After rising to a certain height, the ZCC18000 rotated to drive the cutterhead to "turn" 90 degrees and adjust its posture. Subsequently, the ZCC18000 applied force again to make the cutterhead perform a second 90-degree "turn," so that it precisely aligned with the working shaft, and finally it was slowly lowered into the shaft to connect with the main shield body, with an error of no more than two millimeters throughout the entire process.

The Haitai Yangtze River Tunnel is currently the underwater shield tunnel with the longest distance and largest cross-section in China. Once completed, it will divert traffic from the Sutong Yangtze River Bridge and ease traffic pressure. At the national strategic level, it is of great significance for advancing the development of the Yangtze River Economic Belt and the integrated development of the Yangtze River Delta region, and can strengthen connections between cities on both banks and promote resource sharing. In terms of regional development, it will promote cross-river integration of the urban agglomeration along the Yangtze River, facilitate complementary advantages between Nantong's Haimen District and Suzhou's Taicang City, improve the regional road network layout, and enhance the status of transportation hubs.

The smooth lowering of the cutterhead of the "Jianghai" shield machine into the shaft embodies the wisdom and sweat of the builders and demonstrates China's strength in tunnel construction. In the future, Zoomlion will also continue to support social engineering construction and provide a more solid and smarter equipment foundation for the vigorous development of our beautiful motherland.