Core Viewpoint - The successful launch of the "Cangyuan" shield machine marks the beginning of the shield tunneling work for the world's longest underwater highway tunnel, the Haitai Yangtze River Tunnel, which is 9,327 meters long [1] Group 1: Project Overview - The Haitai Yangtze River Tunnel is characterized by its "long, large, high, and deep" features, making it the longest underwater highway shield tunnel in the world [1] - The construction faces significant challenges, including a maximum water pressure of 0.75 MPa and strict settlement control requirements during the tunneling process [1] Group 2: Technological Innovation - The "Cangyuan" shield machine was specifically designed to address the complex engineering risks and challenges associated with the project, featuring innovations in nine major systems including the cutter head, main drive, thrust, and synchronous grouting [1] - The successful development of the "Cangyuan" represents a significant breakthrough in China's equipment manufacturing sector [1] Group 3: Construction Timeline - The "Cangyuan" shield machine was launched on March 26 and underwent 66 days of assembly and debugging at the construction site before officially starting its tunneling work [1]