On May 16, the super-large cross-section rectangular pipe jacking machine "Kaixuan" (Triumph), jointly developed by China Railway Engineering Equipment Group (CREG), China Railway No.10 Engineering Group, and Zhongyifeng Tunnel, rolled off the production line smoothly in Hangzhou. It will be used as China's first rectangular pipe jacking machine applied to the construction of a metro parking line, for the construction of the parking line at Huajiachi Station on Hangzhou Metro Line 18.

The Huajiachi Station parking line project on Hangzhou Metro Line 18, where "Kaixuan" is deployed, faces challenges including large burial depth (22 m of overburden, currently the largest burial depth among large cross-section rectangular pipe jacking projects), high water pressure (a confined aquifer beneath the pipe bottom with a pressure of 3 kg), a long jacking distance of 252 m, and water-rich soft strata (including silt layers). It is therefore also recognized as a major difficult project on the line. As the equipment supplier, CREG worked with all participating parties on rigorous, targeted design of the equipment, adopting a quasi-rectangular cross-section 12.02 m wide and 8.72 m high, and technologies such as a low-disturbance excavation design with four front and four rear cutterheads, which can effectively meet the equipment's construction requirements for large-depth, high-water-pressure rectangular tunnels. At the same time, it also sets a precedent for the first application of rectangular pipe jacking to the construction of a large-depth, high-water-pressure rectangular tunnel.

Hangzhou Metro Line 18 is also known as the "Hangzhou Metro North-South Express Line." The line runs from Yiqiao Station to Century Avenue Station, with a length of 48 km and 19 underground stations. It is a north-south rail express line. Once completed, it will form a cross-shaped network with the airport rail express line and achieve interconnection with the urban (suburban) railways toward Haining, Zhuji, and Tongxiang, becoming a true "king of transfers" and enabling rapid access between the city's north and south wings and the central urban area.

As a leading enterprise in China's tunnel boring machines, CREG was the first to enter the rectangular pipe jacking field in 2014. The super-large cross-section rectangular pipe jacking machine it developed was successfully used in the Hongzhuan Road underpass tunnel in Zhengzhou, creating a new model for pedestrian underpass excavation in China. Over the years, our technology has continued to iterate and innovate, and a series of products have been successfully applied in projects such as the entrances and exits of Singapore's Thomson Line metro, the underpass at the Huaxi Campus of Sichuan University, the urban expressway underpass project in Jiaxing, Zhejiang, the Shasan Station of Shenzhen Metro, and the Tongxiang highway tunnel in Zhejiang, providing vivid practice for the safety and efficiency of urban underground space development.