Pune: Metro tunnel boring machine reaches Mumbai, work to start in December

PUNE: The first of the four tunnel boring machines to be used for the underground Metro stretch in the city reached Mumbai's Jawaharlal Nehru Port Trust on Wednesday.
The machine, which was shipped from Hong Kong, will reach the work site in Pune within the next few days. After assembling and lowering the machine, the actual excavation is expected to start in the first week of December from a shaft constructed at Agriculture College.The excavation will begin towards the Swargate side.
The Maharashtra Metro Rail Corporation (MahaMetro), which is constructing the 5km underground stretch from Agricultural College up to Swargate, stated that two machines were being procured from a Hong Kong-based company. Another machine would reach the city soon, a MahaMetro official said.
MahaMetro has already started the pre-excavation work in the underground stretch. Digging of the shaft has been complete at Agricultural College and similar work was in progress at Swargate.
The official said, "The machine has arrived in loose parts. It will be assembled at the Agriculture College site and then lowered in to the shaft. The machine is 120m long with a diameter of 6.65m. All four machines will be of international standard. Similar machines were used for underground tunnelling for the Metro in Delhi and Mumbai."
A single TBM was expected to complete tunnelling in about 6-7m in 24 hours, the official said. The machine has a facility to maintain adequate air pressure and oxygen levels.
Two machines will begin excavation from the Swargate end of the tunnel. The four machines will meet at Kasba Peth. The underground stretch will travel via Civil Court, Kasba Peth, Budhwar Peth, Mandai and up to Swargate.