TBM Disha records first tunnel breakthrough on Golden Line of Delhi Metro Phase 4

New Delhi, India (Metro Rail Today): In a major milestone for Delhi Metro Phase 4, Afcons Infrastructure on Tuesday celebrated the first tunnel breakthrough by TBM Disha at Tughlakabad Railway Colony Station, marking significant progress on the 23.622 km Golden Line corridor that will eventually connect Aerocity to Tughlakabad through 16 stations.

TBM Disha, officially designated as S-1264B, is a refurbished Herrenknecht Earth Pressure Balance (EPB) machine. It previously operated under the name TBM Varada, donning an Indian-flag themed cutterhead, and was instrumental in tunneling works for Bangalore Metro’s Phase 2 Pink Line (Package RT-01) between March 2021 and September 2022. After completing its earlier assignment, the machine was refurbished at Butibori near Nagpur, successfully cleared factory acceptance tests (FAT) in October 2023, and was mobilised to Delhi shortly thereafter.

TBM Disha was launched in November 2024 from the Tughlakabad Station on the Golden Line. The machine was tasked with constructing a 959-meter tunnel heading westward toward Tughlakabad Railway Colony Station. According to Delhi Metro Rail Corporation (DMRC), the tunnel comprises 566 rings and has been built at an average depth of 18 meters, underscoring the engineering precision and safety achieved during its execution.

The tunneling is part of Package DC-07, a crucial 6.981 km section awarded to Afcons Infrastructure in January 2022 at a contract value of Rs 1669.20 crore. This section links Sangam Vihar Station’s east-end to Sarita Vihar Depot, including three intermediate stations at Maa Anandmayee Marg, Tughlakabad Railway Colony, and Tughlakabad, where it will eventually interchange with the existing Violet Line from Delhi Metro Phase 2. The project is being implemented under a 42-month deadline.

The parallel tunnel on the same stretch is currently being constructed using Robbins TBM 364, and DMRC anticipates its completion by the end of this month.

With this breakthrough, the Golden Line corridor has now seen a total of 12 tunnel breakthroughs. These include 4 by Afcons for DC-07, 6 by L&T for DC-09, and 2 by J Kumar for DC-08, marking steady advancement across the project’s entire alignment.

As Delhi Metro continues to push forward with Phase 4, the successful breakthrough by TBM Disha stands as a testament to the engineering excellence and coordination between DMRC and its construction partners.