The Indian locomotive class WAG-12B, created in 2017 through collaboration between Alstom and Indian Railways, is a class of 25 kV AC electric locomotives. The name "WAG-12B" signifies its characteristics: broad gauge (W), Alternating Current (AC), Goods traffic (G) locomotive, and a power output of 12,000 hp.
Beginning trial service in 2019, a total of 320 WAG-12B locomotives have been manufactured at the Electric Locomotive Factory in Madhepura, Bihar, India. These locomotives are remarkably powerful, boasting twice the horsepower of their predecessor, the WAG-9. As a result, they stand among the most formidable freight locomotives worldwide.
The primary purpose of the WAG-12B is to operate on the Dedicated Freight Corridors, where it will pull freight trains weighing over 6,000 tonnes (5,900 long tons; 6,600 short tons) at speeds ranging from 100 km/h (62 mph) to 120 km/h (75 mph). This development effectively doubles the average speed of freight trains in this sector, significantly enhancing efficiency and longetivity.
History[]
Origins[]
The inception of the WAG-12B locomotive can be traced back to 2006 when the Government of India approved the Dedicated Freight Corridor (DFC) project and established the Dedicated Freight Corridor Corporation of India Limited (DFCCIL) to oversee its construction. It became evident that even the most powerful locomotive of that time, the WAG-9, would not suffice to ensure optimal train operations on the DFCs. Consequently, a decision was made to procure new and more potent locomotives specifically designed for dedicated operations on the two DFCs, in contrast to the traditional practice of building locomotives at the Chittaranjan Locomotive Works (CLW) under technology transfer agreements with Indian Railways.
In June 2008, the Ministry of Railways invited global firms to submit bids for the design and development of these locomotives. The initial proposal entailed the establishment of a new electric locomotive factory in Madhepura, Bihar, to manufacture and maintain 660 high-horsepower locomotives through a joint venture. Under this arrangement, Indian Railways would hold a 26% stake, while the bidder would hold 74%. This venture would have marked the first foreign direct investment in the entirely state-owned railway sector of India.
Several international companies, including General Electric, Alstom, Bombardier Transportation, Siemens Mobility, China CNR, and CSR Corporation, submitted their bids in response to the invitation. The number of locomotives to be manufactured was subsequently increased from 660 to 800.
In June 2013, the Research Design and Standards Organisation published a specification outlining the necessary capabilities of an eight-axle locomotive intended for use on the Dedicated Freight Corridors (DFC). However, it was not until November 2015 that Alstom was ultimately awarded the contract to build these locomotives.
Development[]
Following the signing of a contract worth ₹25,000 crore (US$4.0 billion in 2020) between the Ministry of Railways and Alstom, the development of the WAG-12B locomotive commenced. A joint venture was established for this ambitious project, representing the largest Foreign Direct Investment (FDI) undertaking of Indian Railways. Initially, the first locomotive was scheduled to enter service by 28 February 2018.
Alstom, in collaboration with Indian Railways, announced that the new locomotive would be based on its highly successful Prima II model and referred to it as the Prima T8. This marked a significant milestone as it had been two decades since Indian Railways procured new locomotives.
However, the official launch of the locomotive took place on 10 April 2018 in Madhepura, Bihar, with Prime Minister Narendra Modi presiding over the event.
Production[]
During the course of development, Alstom decided to outsource certain aspects of the WAG-12B locomotive production to specialized companies. In 2016, the task of manufacturing traction transformers for the locomotives was assigned to ABB, a Swedish-Swiss multinational corporation. These transformers, designed to withstand all weather conditions, were to be produced in Vadodara, Gujarat. Similarly, in 2017, Alstom enlisted the expertise of German brake manufacturing firm Knorr-Bremse to develop, test, and maintain the locomotive brakes. The production of these brakes was planned in Palwal, Haryana. The design and development of the locomotive couplers were undertaken by French railway company Faiveley Transport. The majority of the locomotive components, approximately 85-90%, were to be sourced from within India.
The first body shell of the locomotive arrived at Haldia Port in West Bengal on 20 September 2017 and was subsequently transported to the Electric Locomotive Factory (Alstom Madhepura) for final assembly. The assembly process commenced on 11 October 2017. On 27 February 2018, the first locomotive with the number 60001 underwent testing at the Madhepura factory, just a day before its originally planned launch date.
The delivery schedule for the locomotives spanned from 2018 to 2028. The initial locomotive was expected to enter service in 2018, with a total of five locomotives slated for delivery by 2019. Subsequently, the plan involved assembling 35 locomotives in 2020, 60 in 2021, and 100 locomotives each year from 2022 until all 800 locomotives were delivered.
Design[]
The WAG-12B locomotive is a three-phase, twin-section electric freight locomotive consisting of two identical sections, each resting on two twin-axled Bo-Bo bogies. This locomotive is a collaborative effort between Alstom and Indian Railways and represents the first locomotive in the Indian Railways fleet with a power output exceeding 10,000 horsepower. With a power output of 12,000 hp, it is twice as powerful as its predecessor, the WAG-9, and stands as one of the most powerful freight locomotives globally.
The design of super-high powered locomotives like the WAG-12B necessitates the inclusion of twin sections. The immense power output of 9 megawatts (12,000 hp) cannot be accommodated within the size constraints of a standard locomotive body. The required traction motors for generating such torque would not fit on the axles alone. To ensure optimal load distribution and pulling power, additional axles are needed. However, this would make the locomotive excessively long. As per Indian Railways regulations, railway vehicles cannot exceed 25 meters in length to negotiate turnouts. To address this, a vestibule was added in the middle, resulting in the twin-section configuration of the locomotive.
The eight-axle design of the locomotive offers improved performance, minimized energy consumption, and reduced maintenance costs. It incorporates special features based on the Alstom Prima T8 model, enabling operations in humid or dusty environments as well as extreme temperatures ranging from -50 °C (-58 °F) to 50 °C (122 °F). The locomotive cabin is comparatively larger, providing enhanced comfort for drivers, particularly during long-distance operations. Additionally, the locomotives can be equipped with climate control systems, such as air conditioners, food preparation and storage facilities, and even a toilet, meeting the standard set by Indian Railways in 2016.
The WAG-12B locomotive is equipped with state-of-the-art systems, including GPS and GPRS-based remote diagnostics, tracking, and systems monitoring. It also features wireless control of multiple-unit locomotives, cruise control, autopilot capabilities, and an incident recorder, akin to a "black box." These advanced systems ensure efficient operations, enhanced safety, and comprehensive monitoring of locomotive performance.