On July 30, the "New Crossing" shield machine for the Shanghai Airport Link Line rolled off the production line in Changsha and will soon be transported to the site for assembly and commissioning, marking another step forward in the excavation of the controlling project of Shanghai's first municipal railway.

The "New Crossing" shield machine has a total length of 114 meters and a total weight of about 3,174 tons. The cutterhead is painted with the white magnolia, the city flower of Shanghai, which not only reflects the regional cultural characteristics of Shanghai but also symbolizes the pioneering and enterprising spirit.

The Shanghai Airport Link Line has a total length of 68.68 kilometers and is laid out in a "Y" shape, with 9 stations in total and a design speed of 160 kilometers per hour. It is one of the first 11 municipal railway demonstration lines nationwide approved by the National Development and Reform Commission and is also an important east-west rapid corridor in Shanghai's rail transit network.

It is understood that the shield tunnel of Section 2 of the Shanghai Airport Link Line, constructed by the company, has a total length of 4,939.7 meters and a segment outer diameter of 13.6 meters. It is currently China's first large-diameter shield tunnel running parallel at a small spacing over a long distance to an operating high-speed railway line, and also the first large shield tunnel undertaken by China Railway Construction in Shanghai. Its innovative use of fully precast tunnel structures has also pioneered similar construction techniques.

The shield tunnel passes beneath important structures such as operating rail transit lines, municipal roads, and bridges, imposing high requirements on surface settlement control accuracy and environmental protection. The large curved block at the bottom of the tunnel adopts an integral precast assembly process for the first time, placing high demands on the reliability of the material transport system and assembly precision. The long-distance, large-section crossing of silty clay, sandy silt, and silty sand strata also imposes higher requirements on the shield machine's attitude control, overall sealing performance, and construction.

In response to the project characteristics and requirements, the shield machine was designed with a number of key technologies, including a atmospheric-pressure soft-ground cutterhead, high-pressure main drive seals, a large-flow slurry scouring circulation system, a high-precision gas-liquid pressure balance control system, efficient material transport and high-precision synchronous box culvert assembly technology, and a synchronous backfill grouting compactness detection system, greatly improving the adaptability and reliability of the shield machine and safeguarding the smooth implementation of the project.