The main press station is installed in the start shaft and adjusted as to direction, height and inclination. Then the machine is lowered into the shaft after which hydraulic cylinders press it into the ground. At the same time, the machine's cutter head excavates the soil. The process stops when the hydraulic cylinders have reached their maximum extension. The cylinders are withdrawn and a new tube is installed in the press station. This process is repeated until the tunnel boring machine has reached the target shaft.

The pipe jacking drive unit (main press station) consists of hydraulic press cylinders, a bracing ring, and back and bottom boards. The bracing ring transfers the forces of the hydraulic cylinders to the pipes. The back board supports the shaft walls.

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