Six of the seven cutting-head sections for the Tunnel Boring Machine (TBM) that will excavate Poland's flagship high-speed rail tunnel beneath Łódź have now arrived on site, marking another major milestone for the project.
Construction teams at the K7 launch shaft near Retkinia are continuing the assembly of the giant machine, which will begin boring the 4.6km tunnel in spring 2027. The underground route will connect the launch shaft in western Łódź with the receiving shaft near the Łódź House of Culture, forming a critical section of the country's expanding high-speed rail network.
Six Huge Cutting Wheel Segments Now Installed
The cutting wheel, one of the most important elements of the TBM, is rapidly taking shape. Six of its seven sections have been delivered and installed, with each arm weighing almost 40 tonnes.
Designed to operate at the front of the machine, the rotating cutting wheel is equipped with specialist excavation tools that break up and loosen the ground as the TBM advances. Excavated material then passes through openings in the wheel and into the excavation chamber located behind it.
The arrival of these components represents a significant step towards the completion of the machine's assembly ahead of tunnelling operations next year.
Shield Sections and Hydraulic Systems Taking Shape
Alongside the cutting head, contractors are assembling additional sections of the TBM shield, each weighing between 50 and 65 tonnes.
These sections house the hydraulic thrust cylinders that generate the force required to propel the machine through the ground. As well as driving excavation progress, the shield provides a protective steel structure around the front of the TBM, ensuring safe and efficient underground operations.
A key element currently being prepared is the shield section featuring a circular opening for the installation of the screw conveyor. Once operational, this component will transport excavated spoil away from the excavation chamber during tunnelling works.
Key Infrastructure Project Moves Forward
The ongoing delivery and installation of major TBM components signals the start of another crucial phase in the construction of the Łódź high-speed rail tunnel.
Once fully assembled, the machine will excavate one of the most strategically important sections of rail infrastructure being developed as part of the Port Polska programme. Upon completion, the tunnel will play a central role in improving connectivity and supporting the future growth of Poland's high-speed rail network.
Image credit: Port Polska
