Crossrail’s sixth and seventh tunnel boring machines (TBMs) have completed their factory testing and are set to start their journey to London.
Both machines are in the process of being dismantled, boxed up and transported from the Herrenknecht factory in Germany.
TBM 6, a slurry machine called Mary, will drill a tunnel under the Thames from Plumstead to North Woolwich alongside her sister machine Sophia, who started tunnelling at the start of January.
TBM Mary is named after the wife of the Isambard Kingdom Brunel. It weighs 1,000 tonnes and is 110m long, equipped especially to deal with the chalk, flint and wet conditions of southeast London.
The 150m-long TBM 7 is yet to be named, but will start its operation this summer from Pudding Mill Lane to Stepney Green. It is an earth pressure balanced machine designed for the London clay north of the River.
All the machines’ components are expected to arrive at Crossrail’s sites within the next month where they will be reassembled.
Crossrail’s final tunnel boring machine, TBM 8, will complete factory testing this summer.
Crossrail programme director Andy Mitchell said: “Over 4km of tunnel has now been constructed on Crossrail. With tunnelling now well underway we are looking forward to welcoming our sixth and seventh tunnel boring machines to the project. Once we’ve unpacked and reassembled them, they’ll begin drilling yet more tunnels underneath the streets of the capital.”