The Mumbai Metro Rail Corporation (MMRC), on Friday, achieved the 33rd breakthrough of the 653-m long tunnel from Churchgate to Hutatma Chowk station. It is the first TBM breakthrough inside NATM tunnel employing Robbins-made Dual mode hard rock Tunnel Boring Machine (TBM) Surya-2 which has completed this downline stretch in 275 days using 502 rings.
“The presence of iconic Flora Fountain and various heritage buildings made out task a bit challenging. However, this unique station, in the vicinity of Hutatma Chowk, is being built by using a combination of Cut-and-Cover and New Austrian Tunnelling Method (NATM). This station will provide accessibility to the business centres of South Mumbai”, said Mr. Ranjit Singh Deol, Managing Director, MMRC.
- The overall progress of Hutatma Chowk station is 53%. Package-1, which consists of Cuffe Parade, Vidhan Bhavan, Churchgate and Hutatma Chowk stations, showcases overall 80% tunnelling progress and 68% overall station work progress.
- The total tunnelling of the project completed is 88% and civil work is 60%.
An important equipment, Flash Butt Welding Machine (FBW Machine), which will weld Head Hardened (HH) rails for the 33.5-km long Colaba-Bandra-SEEPZ Metro-3 corridor, has arrived in Mumbai and begun its work at the Chhatrapati Shivaji Maharaj International Airport Station (CSMIA-T2) on 9th Oct, 2020.
- FBW Machine will weld the rails by aligning, preheating, flashing, forging, stripping and air-quenching at a flash voltage of 340V and Boost Voltage of 420V.
- This is first of the two such plants to be deployed.
- “This is an automatic welding machine with pre-set parameters to function exactly as per the set values to produce quality welds. Welding of rails is planned from eleven different locations to cover entire 33.5km project”, informed Mr. Ranjit Singh Deol, MD, MMRC.
- The FBW Machine is manufactured by M/s. Holland LP, USA.
- The second FBW Machine is expected by the end of next month.
- In all 8,366 ton of HH rails, out of 10,740 ton, have already been received by the Mumbai Metro Rail Corporation (MMRC).
- Remaining rails are already shipped from Japan.
Source: MMRC-Press Release