Recently, the first shield machine "Zhenxing No. 1" for the Second Work Section of Phase I of Changchun Urban Rail Transit Line 7 was successfully launched at Qiche Park Station, marking the project's official entry into the shield tunneling construction stage.

The "Zhenxing No. 1" shield machine launched this time is a ZTE6430 earth pressure balance shield machine produced by CRCC Heavy Industry, with a total weight of 503 tons and a length of 86 meters. The section from Qiche Park Station to the depot access line of Phase I of Rail Transit Line 7 has a total length of 1,142 meters. It mainly passes through moderately weathered mudstone in Changchun's harder strata, includes a 350-meter small-radius curve, passes beneath the Changchun Ring Expressway and beneath a DN800 high-pressure natural gas pipeline with a clearance of 3.17 meters between the tunnel crown and the bottom of the pipe, involving high safety risks and great construction difficulty.

To ensure the smooth launch of the "Zhenxing No. 1" shield machine, the Second Work Section project of Phase I of Rail Transit Line 7 planned ahead and organized meticulously, formulating a safe and efficient shield machine launch plan. Through the unremitting efforts of all employees of the project department, a series of launch preparation tasks, including the lowering, installation and commissioning of the shield machine, the gantry crane and ground supporting equipment, were successfully completed, ensuring the smooth launch of the "Zhenxing No. 1" shield machine.

It is understood that Phase I of Changchun Urban Rail Transit Line 7 has a total length of 23.166 kilometers. The construction tasks of the Second Work Section include 5 stations, 6 running tunnels, 1 connecting line and track laying for the entire line, with a total length of 8.21 kilometers, starting from Kaoshantun Depot (exclusive) and ending at Jida Siyuan (exclusive). As a northeast-to-southwest encryption line, the route runs along Dongfeng Street, Nanhu Avenue and Donghuancheng Road, starting from the Kaoshantun depot access line and ending at Donghuancheng Road Station. It strengthens the connection between the automobile development zone in the southwest and the central urban area. In particular, the sections along Nanhu Avenue and Donghuancheng Road have dense populations and jobs and large passenger flows, and are currently major congested areas. Once completed, the line will guide the rational development of Changchun's urban layout.