How a tunnel machine works?
How a tunnel machine works? A Tunnel Boring Machine (TBM) is a large-scale mechanical device used for tunnel excavation, integrating various technologies such as mechanics, hydraulics, electricity, and automatic control. It can efficiently and safely excavate tunnels under various geological conditions. The working principle of a TBM can be broken down into several main steps:
1、Rock and Soil Cutting: At the front of the TBM is a rotating cutting wheel equipped with cutting tools. As the wheel rotates, the tools cut through the rock and soil, breaking it into smaller pieces.
2、Muck Removal: The broken rock and soil enter the TBM through openings on the cutting wheel, and are then conveyed out of the tunnel using conveyor belts or screw conveyors.
3、Advancement: The TBM is propelled forward by an advance system, which typically includes hydraulic cylinders or electric motors. This system moves the TBM forward, while the cutting wheel continuously cuts through the rock and soil, advancing the tunnel.
4、Support: During tunneling, the TBM must support the surrounding rock and soil to prevent collapse. The support system usually includes a shield and support hydraulic cylinders. The shield protects the TBM’s internal components and operators, while the hydraulic cylinders provide the necessary support to maintain tunnel stability.
5、Guidance: The TBM must excavate in the intended direction, and a guidance system helps it maintain the correct course. This system typically includes laser guidance instruments and gyroscopes.
TBMs are widely used in tunnel construction for subways, highways, water conservancy projects, and mines. They not only enhance construction efficiency and safety, reduce environmental impact, but also ensure project quality and economic benefits, marking a significant milestone in modern tunnel construction technology.