Developed by China Railway Construction Corporation, the machine named Gangtie Jiliang boring machine, meaning "steel backbone," is designed for full-face vertical excavation, a method not previously achieved at such depths, according to the South China Morning Post.

Weighing about 500 tonnes and measuring 8.1 meters in diameter, the machine has been described by China's Science and Technology Daily newspaper as resembling an "underground aircraft carrier" rather than conventional mining equipment. It has been deployed at an iron ore project in Liaoning, northeastern China.

The system targets growing demand for deep-earth resources as shallow mineral reserves become harder to find. Mining at such depths has long faced challenges including extreme pressure, high temperatures, and dense rock formations.

Unlike traditional shaft-sinking methods, the machine uses a large circular cutterhead to drill vertically from the surface, similar to an oversized electric drill. It is engineered to maintain continuous and stable excavation in hard rock conditions.

The 500-ton drilling machine Gangtie Jiliang. Photo courtesy of China Railway Construction Corporation

Chief designer Ding Zhangfei told Science and Technology Daily that the team overcame several technical challenges during development, securing multiple patents.

Beyond improving efficiency, the technology may also reduce environmental impact. By enabling more direct access to underground deposits, it could limit large-scale surface excavation, which often leads to land degradation and ecological disruption, according to Interesting Engineering.

Ding said the team plans to expand the machine’s applications to other underground engineering projects, helping China advance in deep-earth excavation technologies.

The system could also support strategic infrastructure development. Chinese energy experts have proposed building deep underground networks in western China to house critical energy and defense facilities, making them more secure and harder to detect.