Chunfeng Tunnel is Shenzhen's first single-hole and double-layer shield-based motor vehicle tunnel. Tunnel Boring Machine work under 30 meter ground. CREC already 1745 meter excavate with CREG Tunnel Boring Machine (CREG TBM). TBM is 6 story high.

China's biggest slurry TBM. This CREG TBM 15.8 meter diameter. Manufactured China Railway Equipment Group (CREG). CREG is subsidiary of CREC.

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