HS2 has unveiled the names of the next pair of tunnel boring machines (TBMs) that will construct the high-speed rail line under the capital: Emily and Anne.
The machines are earth pressure balance TBMs, designed specifically for the soft ground conditions of London clay.
This section of tunnelling will complete the 8.4-mile-long Northolt tunnel, which is being built in two sections.
TBMs Caroline and Sushiula are already boring the western end of the tunnel beginning in West Ruislip and working towards Greenford, with almost two miles completed so far. Emily and Anne will bore the eastern section.
The final section of tunnel from Victoria Road Crossover Box to connect to Old Oak Common Station will be constructed using spray concrete lining.
The new TBMs have been manufactured by Herrenknecht in Germany and each weigh 1,700 tonnes. After being lowered underground into the launch chambers in pieces, they will be reassembled.
Each part of the TBM is lifted using a crane, including the 316-tonne front shield and 336-tonne middle shield. Eight back gantries for each machine will also be lifted into place to provide all the systems required for the tunnelling operations underground.
The major components of the first machine have now been lifted into the 25-metre-deep ancillary shaft in Ealing.
The TBMs will begin their 3.4-mile, year-long journey at the start of 2024, travelling under Ealing from the Victoria Road site towards Greenpark Way in Greenford.
Upon reaching Greenpark Way, they will be disassembled and removed via another 35-metre-deep shaft.
“The London Tunnels programme is reaching its peak delivery stage and we’re excited to name our next two TBMs Emily and Anne.
“They will join our first two TBMs, Sushila and Caroline, who are already one year into constructing the section of tunnel between West Ruislip and Victoria Road.”
The first TBM has been named after the midwife Emily Sophia Taylor, who helped establish the Perivale Maternity Hospital in 1937 before becoming Ealing’s first female mayor in 1938.
The second TBM is named after educational reformer Lady Anne Byron. She established the Ealing Grove School in 1834 – England’s first co-operative school which provided education for the working classes.
Before the launch of Emily and Anne, a blessing ceremony will be conducted by a local priest. This longstanding tunnelling tradition involves a statue of St Barbara, the Patron Saint of tunnelling, being blessed and placed at the entrance of the tunnel.
Next year, HS2 will assemble the final two TBMs, which will tunnel between Old Oak Common and Euston.
