Mumbai–Ahmedabad Bullet Train Project: Second TBM Cutterhead Installed at Ghansoli Shaft

Mumbai, May 23, 2026: The Mumbai–Ahmedabad high-speed rail project achieved a key construction milestone with the installation of the cutterhead of a second Tunnel Boring Machine (TBM) at the Savali (Ghansoli) shaft near Mumbai.

The development is part of the construction of a 21-kilometre underground tunnel section of the high-speed rail corridor.

Key Construction Update

The second TBM cutterhead, weighing approximately 350 tonnes with a diameter of 13.6 metres, was lowered into the Ghansoli shaft. This marks the final stage of the primary assembly of the TBM main shield.

The machine will begin tunnelling from Ghansoli towards Vikhroli after final assembly and commissioning trials.

Earlier this week, the cutterhead of the first TBM was also lowered at Vikhroli, indicating parallel progress on both tunnel drives.

Project Timeline

According to project updates:

Both TBMs will undergo final assembly and commissioning trials
Trial operations are expected to be completed in the coming weeks
Initial tunnelling drives are scheduled to begin in early July 2026

The twin TBMs will be deployed to accelerate underground excavation for the high-speed rail corridor.

Engineering Specifications

The TBMs deployed for the project are among the largest tunnelling machines being used in India.

Each machine includes:

Length: 95.32 metres
Type: Mix Shield / Slurry TBM
Cutterhead diameter: 13.6 metres
Total weight: 3,080 tonnes (TBM 1) and 3,184 tonnes (TBM 2)

The cutterhead is equipped with:

84 cutter discs
124 scrapers
16 bucket lips

These components enable efficient rock cutting and material removal during tunnelling operations.

Operational Capability

The TBMs are designed to operate with:

Maximum cutterhead speed: 4 RPM
Excavation rate: up to 49 mm per minute

The machines are engineered to ensure controlled excavation while maintaining high safety standards for large-scale underground construction.

About the Project

The Mumbai–Ahmedabad high-speed rail corridor is India’s first bullet train project, featuring advanced tunnelling and civil engineering works designed for high-speed rail connectivity between major urban centres.