Recently，The world's longest undersea road tunnel——The Second Subsea Tunnel of Jiaozhou Bay，Weighing 600 tons.“Sea and sky”Shield Machine Cutter Successfully Completed Downhole，About to enter the drilling work。

“Sea and sky”The total length of the shield machine is 142 meters.，Total weight 5166 tons，It is also equipped with a telescopic main drive、Telescopic excavation bin monitoring system and a series of intelligent systems。Tunnel excavation diameter 15.63 meters，Equivalent to a 5-story building。

This time, the cutter head is lowered into the well，Yes“Sea and sky”Key links in the process of lifting and assembling，Beijing Yian Hoisting Engineering Co., Ltd.SCC12000TMThe crawler crane bears the main crane。

Xiao Yingyu of Beijing Yian Hoisting Engineering Co., Ltd.：“The construction site of the second tunnel in Jiaozhou Bay is very limited.，The shield structure is narrower after arriving at the site.。Although only a short distance of movement is require during that hoist process,，But considering the oversized parts,，The requirements for security and stability are high.，Finally, two Trinity crawler cranes were used to work together.，The main crane is an 800-ton crawler crane.SCC12000TM，The other auxiliary crane is a 400-ton crawler crane.SCC4000A-2。”

This construction，Main craneSCC12000TMWorking condition of 42m main boom with 390t super-lift configuration，Lifting radius: 17m、Super-lift radius of 20m。After about 3 hours of operation，The cutter head and the machine body are stably combined together.。

The second tunnel project in Jiaozhou Bay is the largest in the world.、The longest undersea road tunnel，It is also a submarine tunnel with the largest section of drilling and blasting method and shield method.。At present，The Qingdao shield section is planned to be put into operation“National Signal”、“Sea and sky”、“Deep Blue”All three shield machines have been transferred to the project.“Check in”。According to plan，It will be completed and opened to traffic in December 2027.。