WAP-7
CLW made WAP-7 at CLW yard.
Type and origin Power type Electric Builder Chittaranjan Locomotive Works, Banaras Locomotive Works, Patiala Locomotive Works Build date 1999 - present Total produced 1635 as of April 2024
Specifications Gauge 5 ft 6 in (1,676 mm) Bogies Co-Co, Fabricated Flexicoil Mark IV bogies; bogie wheelbase 1,850 mm (72+7⁄8 in) + 1,850 mm (72+7⁄8 in) Wheel diameter 1,092 mm (43 in) new, 1,016 mm (40 in) worn Wheelbase 15,700 mm (51 ft 6+1⁄8 in) Length: ​  • Over beams 20,562 mm (67 ft 5+1⁄2 in) Width 3,152 mm (10 ft 4+1⁄8 in) Height: ​  • Pantograph 4,255 mm (13 ft 11+1⁄2 in) Axle load WAP 7 20.5 t (20.2 long tons; 22.6 short tons)[1] WAP 7HS 18.08 t (17.79 long tons; 19.93 short tons)[2] Loco weight 123 t (121 long tons; 136 short tons)[3] Power supply 3-phase 2180 V 50 Hz Electric system/s 25 kV 50 Hz AC Overhead Current pickup(s) Pantograph Traction motors 6FRA 6068 3-phase squirrel-cage induction motors 850 kW (1,140 hp), 2180 V, 1283/2484 rpm, 270/310A; Weight-2,100 kg (4,600 lb), forced-air ventilation, axle-hung, nose-suspended; Torque 6,330–7,140 N⋅m (4,670–5,270 lbf⋅ft) ~88% efficiency. Transmission Electric Gear ratio WAP 7 72:20 WAP 7HS 70:22 Loco brake Air and regenerative Train brakes Air
Performance figures Maximum speed 140 km/h (87 mph) (WAP-7) 160 km/h (99 mph) (WAP-7HS) Potential speed: 180 km/h (110 mph) (WAP-7HS) 155 km/h (96 mph) (WAP-7) Power output Max Power : 6,350 hp (4,740 kW) Continuous: 6,120 hp (4,563.68 kW) Tractive effort Starting : 322.4 kN (72,500 lbf) Continuous : 228 kN (51,000 lbf) at 71 km/h
Career Operators Indian Railways Numbers 30201+ CLW 37001+ BLW 39000+ PLW Locale India First run 19 May 2000

The Indian locomotive class WAP-7 is a class of 25 kV AC electric locomotives that was developed in 1999 by Chittaranjan Locomotive Works (CLW) for Indian Railways. The model name stands for broad gauge (W), AC Current (A), Passenger traffic (P) locomotive, 7th generation (7). They entered service in 2000. A total of 1609 WAP-7 have been built, with more units being built at CLW, Banaras Locomotive Works (BLW) and Patiala Locomotive Works (PLW).

The WAP-7 is the most successful locomotives of Indian Railways serving passenger trains for over 23 years. It is a passenger variant of the WAG-9 freight locomotive with a modified gear ratio to pull lighter loads at higher speeds. With an output of 6125HP, it is the most powerful passenger locomotive in the Indian Railways fleet, and the most numerous passenger locomotive in India. The WAP-7 is capable of hauling 24 coach trains at speeds 110–140 km/h (68–87 mph).

History

It is now largely used by Northern Railways (NR), South Central Railways (SCR), Central Railways (CR), South East Central Railways (SECR), South Eastern Railways (SER), West Central Railways (WCR), Eastern Railways (ER), Western Railways (WR), North Central Railways (NCR), South Western Railways (SWR), Southern Railways (SR), East Central Railways (ECR), East Coast Railways (ECoR), North Eastern Railways (NER), North Western Railways (NWR) etc. among other zones. As of October 2021, all of which are fitted with H-type transition couplers which are compatible with both screw coupling and centre-buffer coupling. In February 2017, Banaras Locomotive Works built their first WAP 7 class locomotive.^[4]

In 2019, a variant of the WAP-7, designated the WAP-7HS, was introduced for higher speeds. The WAP-7HS has a max speed of 180 km/h (110 mph), and is capable of hauling a 24-car train at 160 km/h (99 mph) as opposed to the 140 km/h (87 mph) of the original. Indian Railways plans to use the WAP-7HS for Shatabdi, Rajdhani, and Duronto express trains. However, as of September 2022, it has not been confirmed if any others have been built, and the single completed WAP-7HS has stayed restricted to 130 km/h (81 mph).

Head-on Generation (HOG)

A main feature of Majority locomotives of this class is that they eliminate the need to have separate End on Generation (EOG) sets or DG (Diesel Generator) sets for supplying power to the train resulting in significant savings on maintenance and running costs. This technology, called HOG or "Head On Generation", transfers electric power from the loco's pantograph to the coaches instead of EOG where a power car equipped with diesel generator capable of generating adequate power of 3-phase 50 Hz 415 V / 750 V AC (called 'head-end power') is provided at either end of the train rake to supply power.^[5][6][7]

Locomotive sheds

Gallery

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  Howrah based WAP7 on lead with 02302 New Delhi - Howrah Rajdhani Express Special at Janai Road
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  LGD WAP-7 30306 at Bangalore
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  Vijayawada WAP-7 39155 with 12075 Kozhikode Main Thiruvananthapuram Central Jan Shatabdi Express Skipping Thuravoor Railway Station in Kerala.
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  New Delhi-Lucknow Tejas Express powered by WAP-7, standing at New Delhi.
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  WAP-7 #30261 charging on time running 22416 NDLS-VSKP A.P. A.C. Express.
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  A Ghaziabad-based WAP-7 hauling the Bhubaneswar Rajdhani Express
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  WAP-7 with the Bangalore Rajdhani Express near Lingampally Railway Station
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  RPM based WAP-7
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  Jammu Tawi bound Humsafar Express leaving Kazipet Junction, hauled by VSKP WAP-7 No. 37062
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  12737 Goutami Express at Moula-ali with a WAP-7 loco
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  Ghaziabad-based WAP-7 locomotive at Anand Vihar Terminal