Just two months after its acceptance at the Nansha plant, Herrenknecht's XXL Mixshield "Yongping" begins its tunnel drive on March 29, 2021. Trains will soon be rolling through the undersea tunnel to be built at a speed of 350 kilometers per hour. The "Shantou Bay Sea Crossing Tunnel" is an important sub-project of the new Shantou-Shanwei railroad station. 

Over 2,169 meters of the 9,191-meter-long tunnel, the TBM passes under the Zhongtai overpass, the Shenhai high-speed rail line, the Huaneng waterworks and several other buildings and residential areas. The Mixshield faces complex soil layers of silt, clay, sand and granite with compressive strengths of up to 106.9 MPa and a maximum water pressure of 5.4 bar.

The 14.52-metre-wide mixshield is equipped with a DCRM system for monitoring the cutter tools and an extendable main drive. Special anti-corrosion measures protect the machine from corrosion caused by seawater.