On June 10, the "Tielong No. 10" shield machine for the right line of the Nanwan Station–Sifangchang Station section of Qingdao Metro Line 15 was successfully launched. Just as the left-line "Tielong No. 9" completed its first hundred rings of tunneling, the right-line "Tielong No. 10" advanced to join it, and the "brother" shield machines were smoothly brought online to "join hands" and embark on a new journey.

The "Tielong No. 10" shield machine launched this time undertakes the tunneling task for the right line of the Nanwan Station–Sifangchang Station section. The machine was launched in split mode from the section's ventilation shaft, tunneling eastward along Jinhong East Road through moderately and slightly weathered andesite, passing through the Hongjiang River fracture zone and the upper-soft/lower-hard strata, and passing alongside the Hongjiang River bridge piles to reach the small-mileage end of Nanwan Station, completing half of the construction task. After reception, it will be relocated to the section's ventilation shaft for a second split launch, tunneling westward along Jinhong East Road, crossing the Tiejiazhuang fault zone, and reaching Sifangchang Station to complete the entire construction task.

The "weight" of the "Tielong No. 10" shield machine is comparable to that of "Tielong No. 9," and its performance and overall configuration are also extremely similar. The "two brothers" have worked hand in hand, having previously participated in metro construction in Hangzhou and Shenzhen before traveling far and wide to the beautiful coastal city of Qingdao. In light of the engineering geological characteristics of this section, the project team conducted in-depth research on equipment selection, focusing on how to improve rock-breaking capability, reduce wear on the cutterhead and cutting tools, prevent mud cake formation, and lower the probability of machine jamming when the shield machine tunnels through hard rock, mudstone, upper-soft/lower-hard strata, and fracture zones. Tailoring the machine to these conditions, they equipped it with a total of 121 disc cutters, cutting knives, and edge scrapers, and optimized the center cutter spacing; targeted wear-resistant protection measures were added to each part of the cutterhead, such as surfacing the cutterhead face with special wear-resistant material, welding a wear-resistant ring with embedded alloy on the cutterhead periphery, and welding dense wear-resistant mesh on the cutterhead edge transition zone, the cutterhead muck inlets, the back of the cutterhead, and the corner transition zones of the cutterhead support legs—truly giving it "sharp teeth."

At the same time, the muck inlets of the "Tielong No. 10" shield machine adopt a conical design, and the support rib plates at the muck inlets adopt a Z-shaped design. This special design facilitates the smooth flow of muck into the soil chamber and prevents blockage of the muck ports. The screw conveyor adopts a shafted screw and a double-discharge-gate structure, and the barrel is provided with multiple inspection doors and injection ports through which bentonite or foam can be injected to improve the fluidity of the muck and ensure its smooth discharge, enabling the equipment to "take in smoothly and discharge smoothly," thereby greatly improving work efficiency.

A month and a half ago, "Tielong No. 9" was successfully launched under the supervision and guidance of the Qingdao Municipal Public Utility Engineering Quality and Safety Supervision Station, and to date it has completed the construction task of one hundred rings. The construction unit summarized the various construction parameters from the past hundred rings, providing a foundational guarantee for the safe launch and efficient tunneling of "Tielong No. 10."