LUCKNOW: Keralam's sharp three- and four-degree railway curves limit the speed of Vande Bharat trains, but technologies such as canted turnouts could help trains negotiate some constrained locations faster without major changes to the existing alignment, according to senior officials at the Research Designs and Standards Organisation (RDSO) in Lucknow.
The assessment is significant because RDSO is the Railways' technical arm responsible for research, design and development, technical standards and specifications, as well as technical advice on railway infrastructure and operations.
As a train negotiates a curve, it experiences greater centrifugal force. To keep the ride safe and comfortable, the train's speed must be reduced. "A canted turnout is a track arrangement in which the outer rail is raised slightly at the turnout, helping trains negotiate the curve more smoothly and at higher speeds," Amit Srivastava, Executive Director (Research), RDSO, told TNIE
Explaining the improvement such changes can bring, Srivastava said earlier, the permissible speed in sharp curves was 15 kmph. "We improved it to 30 kmph, and now we are working towards 45 kmph." the official said.
But turnouts are only part of the challenge. For substantially higher speeds, the more effective solution is to make the curve itself more gradual by increasing its radius. That, however, can mean shifting the entire track alignment.
This could bring the difficult question of land acquisition into the picture, particularly around older stations and in places where houses and other structures have come close to the railway line. "Realigning the track could also require changes to signalling infrastructure because track points and off-takes are linked to the signalling system," Srivastava said.
Manish Thapliyal, Executive Director (Rolling Stock), RDSO said the state's terrain and sharp curves were important reasons for the speed restrictions. At the same time, improvements are possible. "After modifications to ease the curves, speeds have increased to 100 and 110 kmph in most parts of Kerala. Even 130 kmph is possible in parts of Kerala," the official said.
The issue comes as the Railways examines higher-speed potential on Kerala's network. Railway Minister Ashwini Vaishnaw had informed Parliament in February that surveys had been sanctioned for seven projects in the state with potential to support speeds of up to 160 kmph.
The RDSO officials stressed that the Vande. Bharat train's capability itself does not determine how fast it can operate. The permissible speed must be worked out section by section, based on track geometry and other engineering limitations, they said.