CREG Phosphate Mine Hard Rock TBM Breakthrough

On Jan. 18, 2024, the Φ5.48m hard rock TBM developed by China Railway Engineering Equipment Co. Ltd. (CREG) broke through on Hubei Maping Phosphate Mine Inclined Shaft project in China.

This project is the first one in the phosphate mine field that uses a hard rock TBM to excavate. It is 6,427m long in total with the minimum curve radius of 480m. The section 1 of the project is 2,311m long with the maximum longitudinal slope of -12.9%, which was broken through in November 2022. The section 2 is 4116m long with the maximum longitudinal slope of 11.4%. During the excavation, the TBM confronts with half-face overcutting, downhill tunneling with a large slope, uphill tunneling, poor stability in surrounding rock, water ingress, leakage water backflow and other difficulties

To overcome these unfavorable geological conditions, the TBM is equipped with an advanced geological prediction system to achieve the precise identification of geology in front of tunnel face, and innovatively applies the synchronous excavation chamber dewatering technology during the large-slope downhill tunneling. The TBM achieved the maximum monthly advance of 526m and daily advance of 38m.

In recent years, CREG has overcome construction difficulties in non-coal mine tunnels by technology and product innovations, and has manufactured a batch of non-coal mine hard rock TBMs for copper mine, iron mine, lead, zinc and silver ore to satisfy the diversified needs of customers.