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Metro Tunnel

TBM Joan cutterhead installed

Posted: 01 Aug 2019

The Metro Tunnel Project’s first tunnel boring machine (TBM) is in the final stages of assembly, with a 100-tonne red cutterhead installed on the state-of-the-art tunnelling machine.

The cutterhead – which can cut through rock six times harder than concrete – is the heaviest piece of the TBM at over 100-tonnes.

The TBM will now be moved into a steel bell, an innovative launching method for the tunnel boring machines that enhances the initial excavation and provides greater ground support control.

Once the TBM is inside the steel bell, additional pieces of the machine will be lowered into the station box and assembled.

The red TBM, named after Victoria's first female Premier Joan Kirner, will then be launched from the new North Melbourne Station site in the coming weeks as it starts 24-7 tunnelling towards the western tunnel entrance in Kensington.

Find out more about our TBMs and their journey.