【Ten Years of Rapid Development in Chemical Engineering Equipment】The tunnels of the Yangtze River tunneling project were fully completed between 2015 and 2022

The China-Russia East Route Yangtze River tunneling project is the first key control project to be initiated independently by the Pipeline Network Group since its establishment; it represents the \"vital link\" in the China-Russia East Route, which serves as a major energy artery. The section of this project that lies on the China-Russia East Route (Yongqing, Hebei – Shanghai) is connected to existing pipelines such as the West-East Gas Pipeline Line 1 and Line 2. With an annual gas transport capacity of 18.9 billion cubic meters, it helps reduce carbon dioxide emissions by 81.44 million tons, sulfur dioxide emissions by 900,000 tons, nitrogen oxide emissions by 230,000 tons, and dust emissions by 420,000 tons. It contributes to improving the regional air quality, increasing China’s supply of clean energy, optimizing the energy structure, and establishing a clean, low-carbon, safe, and efficient energy system, thereby helping to achieve the goals of carbon peak and carbon neutrality. The China-Russia East Line (Yongqing, Hebei – Shanghai) section was officially launched at the end of July 2020, and its construction was accelerated in January 2021; full connectivity across the entire line is expected to be achieved by 2025. Upon completion, it will enable the smooth delivery of \"Gazprom\" gas, which passes through the three northeastern provinces and the Beijing-Tianjin-Hebei region, to the Yangtze River Delta area, thereby enhancing the region’s capacity for emergency gas supply.

The oil and gas pipeline’s “longest tunnel in the Yangtze River” – It is understood that this project involves crossing the Yangtze River through a tunnel, and the construction conditions are complex as well as the construction process extremely difficult. The excavation of the north bank shaft in Haimen and the lifting and installation of the tunnel boring machine were completed earlier; now, the tunnel boring operations will commence. With a total length of 10.226 kilometers, it is currently the longest shield tunnel in the world for one-way shield tunneling in the oil and gas sector. It is also the first long-distance underwater tunnel in China to be excavated using a single shield machine over such a great distance ； At the lowest point of the project, the elevation of the tunnel roof is -60.2 meters, and the maximum cover thickness is 42.5 meters; these values represent the maximum depths required for the shield tunneling design of oil and gas pipelines ； The water pressure used in shield tunneling construction is 0.73 MPa, making it the shield tunneling project with the highest water pressure to date ； The tunneling excavation diameter is 7.95 meters; the inner diameter of the tunnel is 6.8 meters, while the outer diameter is 7.6 meters. Three pipes with a diameter of 1422 millimeters will be installed inside the tunnel, making it one of the projects with the largest pipe diameters in the world for gas transportation. The “Changtong” shield machine, developed specifically for this project, is the world’s first shield machine with a minimal diameter and a constant-pressure cutterhead. It was completed at the end of March 2021, and on-site assembly and testing began in April. Next, the “Tongchang” tunneling machine will take on this important task, digging at a rate of 450 meters per month in order to set five world records in the field of oil and gas.