~ This milestone strengthens India’s three-stage nuclear programme and advances energy self-reliance through indigenous engineering~

Bangalore : India has taken a significant step forward in its civil nuclear programme with the Prototype Fast Breeder Reactor (PFBR) at Kalpakkam achieving criticality, marking progress into the next stage of its three-stage nuclear energy roadmap focused on long-term energy security and efficient fuel utilisation. The Precision Engineering business of Godrej Enterprises Group has contributed to this milestone by manufacturing and supplying the Large Rotating Plug (LRP), Small Rotating Plug (SRP), and the Sodium Pump Shaft.

These components combine large-scale fabrication with high-precision engineering. The rotating plugs, measuring up to 8 metres in diameter with a combined weight of nearly 120 tonnes, are designed to rotate 360 degrees and align with exact precision to enable fuel insertion into the reactor core. The 10-metre-long sodium pump shaft operates at over 500 RPM in a liquid sodium environment, requiring stringent control over balance, material integrity, and operational reliability. These components were designed and manufactured in India without any prior domestic reference, making this a first-time-right achievement for a first-of-its-kind application.

The execution of these systems involved overcoming multiple engineering challenges, including the development of specialised bearing systems, surface treatment processes for friction control, and gear systems designed to operate under stringent conditions, including seismic requirements. These solutions were developed and manufactured indigenously, reflecting strong in-house engineering and manufacturing capabilities. The components are supplied to The Bharatiya Nabhikiya Vidyut Nigam Limited (BHAVINI) a wholly owned Enterprise of Government of India.

The PFBR achieving criticality marks the culmination of a 22-year effort and a key step in India’s three-stage nuclear programme. Fast breeder reactors enable a closed fuel cycle by using plutonium from PHWRs and producing more fissile material, while also unlocking thorium utilisation. Typically, four PHWRs can fuel one fast breeder reactor. India currently operates 19 PHWRs, with 10 more 700 MWe units sanctioned. With ~846,000 tonnes of thorium reserves, this stage is critical to scaling domestic, low-carbon, and self-sustaining energy.

Godrej Enterprises Group continues to support India’s strategic and industrial capabilities through advanced engineering, delivering high-precision solutions across sectors that are critical to national development.