Metro Rail Technology: On Fast Track

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It is estimated that by 2030, 40 percent of India will be residing in cities. This working class of population contributes significantly to the GDP of the country. Metro rail technology will be the future of travel for most of this urban population – smart, fast,convenient and cost effective. A report by Rachita Jha, Elets News Network (ENN)

Indian Rail transport network is the fourth largest network in the world and has been a major carrier of freight and passenger traffic across many locations nationwide. With accelerated growth of population in cities and limited road infrastructure, future smart cities are optimistic about metro rail as a mode of mass transport.

Growth Outlook
As per the urban transport policy of India, metro rail technology (MRT), a proven and established solution in urban mobility, is envisaged in cities with population exceeding 2 million and is presently being mooted in more than 20 cities. The required investment for the projects is around Rs 2 lakh crore, including rolling stock portion of Rs 50,000 crore approximately. With most of the work already underway for major metro cities such as Delhi, Kolkata, Mumbai, Bangalore, Hyderabad and Chennai, the next phase of mass rapid transit systems is planned for smaller cities of Jaipur, Kochi, Lucknow, Kanpur, Nagpur, Patna, Ludhiana, Indore, Pune and Chandigarh and Ahmedabad. “We are already working on DMRC Phase-III project for 366 metro cars with option of additional 150 cars, with BMRCL for intermediate cars to augment the existing 3-car train sets to 6-car train sets, Jaipur Metro to supply 64 additional cars and Kochi Metro rolling stock requirement of 75 cars with option of additional 75 cars, which is in bidding stage,” informs P Dwarakanath, CMD, Bharath Earth Movers Limited (BEML).

Cities Network
The country is urbanizing fast, and the urban population now exceeds the rural population. This rising population will require mass transport for their mobility. A mass transport system will also help people move to the suburban areas instead of staying in the more congested central areas. Use of MRT will reduce fuel consumption, pollution, health hazards, stress of driving, etc., thereby uplifting the socio-economic status of the country.“In addition many functioning metros are planning to expand their operations. Delhi Metro Railway Corporation (DMRC) is planning to double its network within National Capital Region (NCR), besides expanding to neighboring cities like Sonepat and Panipat in Haryana, Alwar in Rajasthan and Meerut in Uttar Pradesh. Bangalore Metro, Chennai Metro, Jaipur Metro have plans to implement Phase-II of their metro rail projects”, avers Dwarakanath. Most of the other Metro Rail projects planned are in the final stages of Detailed Project Report (DPR) approval. The cities which are well ahead in the planning stage include Lucknow, Nagpur, Pune, Chandigarh, Bhopal, Patna, Indore, Kanpur and Ludhiana.

Case Study – Jaipur Metro

The Jaipur metro project was taken up by BEML with a challenge to design the bogie with a capability to negotiate 120m track curve. The order was to supply 10 train sets of 4 car formation – DTC (Driving Trailer car) + MC (Motor car) + MC + DTC.
Project Specifications
Gauge                          1435 mm
Max Speed                   85 kmph
Axle load                     16 tonnes
Passenger capacity    1312 (4 car)
Carbody                       Austenitic Stainless steel
Bogie                           Bolsterless, air spring in secondary, conical rubber in primary
Brake                           Microprocessor controlled EP + ED brake, disc brakes on wheel
Current collection         25 Kv AC, through pantograph
Propulsion                   IGBT Converter-Inverter, VVVF controls, AC traction motor

New Technologies
“The latest technologies in the metro rail system include driverless train operation and Unattended Train Operation using Communication Based Train Control (CBTC) signaling with moving block technology instead of present fixed block technology. This will improve the performance of the metro system through improved service headway,” avers Dwarakanath. Higher motorization of 67 percent will lead to higher energy efficiency, as more energy will be regenerated by the trains back to the grid. Critical systems like propulsion, brake, door, HVAC, PA/PIS, etc are software controlled for increased efficiency and safety. Fire retardant materials for minimizing fire hazards and ensuring safety and bogie design to suit tighter curves, reduced lateral forces, wheel wear, better suspension characteristics to improve ride comfort among others.

Local Manufacturing
India is encouraging indigenization through local manufacturing and transfer to organizations executing the metro projects across the country. “We had mentioned the condition of local production of rail coaches in our tenders that the production will happen close to Chennai. In our current inventory of 42 trains, we have only 9 trains that have to be imported and 33 trains have to be manufactured locally. This is under our indigenization plan and considers the important aspect of transfer of technology from abroad to India for coach manufacturing. This has not only helped in local employment, technology transfer but also reduced the costs. This will also give a push to modernization of technology capabilities to the country to export coaches to other countries in future,” says Pankaj Kumar Bansal, Managing Director, Chennai Metro Rail Limited.
Delhi-based Bombardier Transportation handles the complete range of railway vehicle manufacturing, software development, and customer service competencies. It has built up its capabilities over four decades of operations. Its large manufacturing presence in India combined with its local experience, international expertise and eco-friendly technologies means it is ideally suited to take India onto the world stage in terms of rail transportation. The company can not only address the country’s rail industry requirements for the production of metros, electric multiple units and locomotives, advanced IGBT propulsion systems and signaling systems, but also supply state-of-the-art made-in-India trains to neighbouring markets in the region.
The company has a state-of-the-art facility in Savli in Vadodara, Gujarat. With that investment, Bombardier proudly became the first foreign multinational company to set up a wholly-owned railway-manufacturing plant in India for the production and final assembly of bogies and car bodies. The Savli site is Bombardier’s largest investment of Rs 230 crores, built in a record time of just 18 months, making Vadodara the only city in the world with the capacity to deliver all key electrical and mechanical components for the manufacturing of railway vehicles. Bombardier Transportation is also one of the first companies to use robotic welding technology in car bodies manufacturing in India. As for indigenization, Bombardier has so far achieved an indigenization level of approximately 75 percent in terms of subsystem indigenization.

Challenges
A major challenge for the project partners is that since the design keeps on changing from project to project, dedicated production lines are required. Also, sourcing of key aggregates – alternate sources, vendor development, low quantities in certain projects, procurement norms is a hurdle. “Maintaining quality as per international standards in Indian conditions, lack of complete testing infrastructure within the country and to match technology changes at a fast pace with continuous knowledge upgrades & manpower training is a challenge,” says Dwarakanath. In addition, ensuring periodic maintenance of vehicles during service as a high reliability and availability is essential for the suppliers of the project at regular basis.

Future Footprint
The success of Delhi Metro has prompted other cities to think of adopting similar mass transport modes. The various mass transport technologies include Bus Rapid Transport (BRT), Monorail, Light Rail Transit (LRT), and high capacity metro rail. “Depending on the requirement for the city, the appropriate mode needs to be selected. In order to address the needs of Tier-II & III with population of million plus and peripheral feeder lines of Tier -I cities having a lower PHPDT market demand is envisaged for LRT. Such systems will be eco friendly and shall meet the green norms. Similarly, for shorter travels, buses using un-conventional fuel electric, hybrid, etc are expected to be introduced,” suggests Dwarakanath. This is in-line with the vision of Urban Development plan in the country.

Stages of Development

Design Stage
At the design stage, 3D CAD was used for design, digital mock ups, integration of various systems and aggregates and generation of manufacturing drawings using tools like CATIA V5 and Pro Engineer. In addition, CAE tools were used extensively to carry out simulations. Finite element analysis was done for all load bearing structures like car body, bogie frame and other critical parts. Typically, Hypermesh with Nastran and Ansys are used for this purpose. Crash analysis for the complete car body was also simulated and studied using LS Dyna tool. CFD analysis was done for HVAC thermal comfort & air flow studies using Star-CD tool. Finally, a vehicle dynamic analysis was done to know more of the behavior of the complete vehicle under all the probable loads, wheel and track situations. The specialized VAMPIRE software is used for this purpose.

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Development and Production Stage
Considering the stringent delivery timelines imposed by JMRC/DMRC, the development and production were the critical stages of the project. The challenge was to source critical aggregates in time and positioning them at appropriate stages of manufacturing. Some of these items included propulsion system; inter vehicular coupler, door system, gangway, wheel and axle, brake system, interior panels and cab equipment etc. Continuous monitoring, co-ordination and discussions were required with vendors at all the stages of manufacturing. Strict quality control systems were followed in all the stages of manufacturing.



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Pankaj Kumar Bansal
Managing Director, Chennai Metro Rail Ltd

“We had mentioned the condition of local production of rail coaches in our tenders. In our current inventory of 42 trains, 33 trains have to be manufactured locally. This is under our indigenization and transfer of technology strategy.” 


Testing and Design Validation Stage
Type testing and design validation to prove the design was a big challenge. All the critical aggregates were type tested for required performance & functionality. Vehicle level type tests were also carried out. These include the fatigue testing of bogie frame for 10 million cycles, wheel unloading test, bogie – carbody interference test, bogie rotational resistance test, etc. Vehicle level test and performance validation was done and RDSO/DMRC conducted oscillation trials and brake tests at site. The dynamic performance of the vehicle under all conditions was highly satisfactory.