A shield tunneling machine recently passed inspection by the China Railway Heavy Machinery Group and will be exported to Colombo, capital of Sri Lanka.

The piece of equipment, with a diameter of 3.7 meters, is the first of its kind to be exported from China to Sri Lanka. It is relatively small, but includes all the necessary functions and matches larger machines in terms of performance and efficiency.

Zhang Ruilin, program manager and directing designer, said that engineering tunnels are composed of extremely hard rocks such as gneiss, which has a compressive strength of 150MPa, equal to the pressure of 15 African elephants standing on one hand. The shortest turning radius in the tunnel is only 80 meters, while the average among such machines is 250 meters, making them difficult to operate. The one exported to Sri Lanka bears distinct Chinese characteristics and major parts are customized to fit the narrow tunnel space of local drainage pipes.

The Sri Lankan government started international bidding for the project to prepare for the summer flood in Colombo. The project will be carried out by the China Petroleum Pipeline Bureau, and the exported equipment is expected to start operating this April.