Northern Shaft Shield Machine: The “Underground Pioneer” of Energy Storage Power Stations

The borehole-expanding shaft tunnel boring machine (TBM) developed by Northern Heavy Industries for a pumped-storage power station in Zhejiang Province is an underground pioneer in shaft construction for power stations, revolutionizing the inefficient and high-risk nature of traditional blasting methods. Traditional shaft construction is extremely challenging due to the confined space and complex geology. However, this TBM’s innovative “conical cutterhead + borehole-expanding and slag removal” design is a key feature. The cutterhead is conical, with a diameter gradually expanding from 3 meters at the top to 6 meters at the bottom. During construction, the top cutterhead first excavates a pilot hole, and then the bottom cutterhead expands the hole, resolving the problem of traditional TBMs’ limited rotation in the shaft. The slag removal system utilizes a combination of a screw conveyor and negative pressure suction to rapidly transport slag to the surface, increasing slag removal efficiency by 50% and preventing slag accumulation from blocking the construction corridor. During the manufacturing process, the equipment applied 3D intelligent modeling technology to simulate the assembly precision of the cutterhead and fuselage in advance, with an error control of 0.1 mm. Laser cutting and robotic welding processes were used to increase the strength of key welds by 20%, ensuring that the equipment would not leak when subjected to high pressure in a vertical shaft 200 meters underground. Since its commissioning, this equipment has increased shaft construction efficiency by three times compared to traditional blasting methods, achieving “zero accident” operations. This provides new equipment support for the rapid construction of pumped-storage power stations in my country and opens up new directions for the cross-scenario application of shield machine technology.