Another major engineering task completed on Mumbai-Ahmedabad Bullet Train Project
By Arun Kumar Das
Mumbai, May 24: In further progress on the Mumbai-Ahmedabad Bullet Train project, a cutterhead for the second Tunnel Boring Machine (TBM) has been lowered at Sawli (Ghansoli) near Mumbai, a task considered gigantic in the railway sector.
The second TBM will start its journey from Sawli (Ghansoli) near Mumbai and move towards Vikhroli, said the National High Speed Rail Corporation (NHSRC), which is entrusted with the construction work.
With a diameter of 13.6 meters, weighing a massive 350 tonnes, this component marks the final step in the primary assembly of the TBM’s main shield.
Cutterhead for the first TBM was lowered earlier this week at Vikhroli. Both the TBMs will now undergo final assembly and commissioning trials before proceeding their initial drive in the first week of July 2026.
With a diameter of 13.6 meters, the cutterhead is designed to excavate a single tunnel large enough to accommodate both the up and down lines of the high-speed corridor.
The unit is equipped with 84 cutter discs, 124 scrapers, and 16 bucket lips to efficiently cut and remove muck during excavation.
Till now two TBMs have been received for the Bullet Train project.
While weight of TBM 1 is 3080 tons, weight of TBM 2 is 3184 tons with cutter head diameter is 13.6 m.
Each TBM measures 95.32 meters in total length and comprises several critical components, including the cutter wheel, main bearing, jaw crusher, erector, main shield, tail shield, and four specialized gantries that support tunnelling operations.
These machines can operate at a maximum cutterhead speed of 4 RPM (revolutions per minute), with a maximum excavation rate of 49 mm per minute, enabling steady and controlled tunnelling progress while maintaining high safety standards.
