Indian locomotive class WAP-1

WAP-1
WAP-1 in Delhi
Type and origin
Power type Electric
Builder Chittaranjan Locomotive Works, West Bengal, India
Build date 1980–1996
Total produced WAP-1: 65
Specifications
Configuration:
 • AAR C-C
 • UIC Co′Co′
Gauge Broad gauge|1,676 mm (5 ft 6 in)
Bogies Flexicoil (cast steel bogies); primary and secondary wheel springs with bolsters
Wheel diameter New:1,092 mm (3 ft 7 in)
Half worn: 1,055 mm (3 ft 5+12 in)
Full worn: 1,016 mm (3 ft 4 in)
Length 18.794 m (61 ft 7+2932 in)
Width 3.179 m (10 ft 5+532 in)
Height 4.272 m (14 ft 316 in)
Axle load 18,800 kg (41,400 lb)
Loco weight 112,000 kg (247,000 lb)
Electric system/s 25 kV 50 Hz AC Overhead
Current pickup(s) pantograph
Traction motors Alstom/CLW TAO 659
Loco brake Air
Train brakes Air ,Dual
Safety systems Slip control, over-voltage relay, main overload relay, earth-fault relay, low-pressure governor, brake cylinder cutoff valve, train parting alarms and No OHE volt relay
Performance figures
Maximum speed 130 km/h (81 mph)
Power output Continuous: 3,800 hp (2,834 kW)
Tractive effort Starting: 22,400 kgf (220 kN; 49,000 lbf)
Career
Operators Indian Railways
Numbers 22000–22076, many being converted to WAP-4
Locale All over India
Disposition Active

The Indian locomotive class WAP-1 is a class of 25 kV AC electric locomotives that was developed in 1980 by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge (W), AC Current (A), Passenger traffic (P) locomotive, 1st generation (1). They entered service in late 1981. A total of 65 WAP-1 were built at CLW between 1980 and 1996, which made them the most numerous class of mainline electric passenger locomotive until its successor, the WAP-4.

The WAP-1 is India's first dedicated electric passenger locomotive of Indian Railways serving passenger trains for over 42 years. This class provided the basic design for a number of other locomotives like WAP-3 and WAP-4 models. However, with the advent of new 3-phase locomotives like WAP-5 and WAP-7, the WAP-1 locomotives were relegated to hauling smaller express and passenger trains and now the aging fleet the WAP-1 locomotives are being slowly withdrawn from mainline duties and scrapped.

As of June 2022, 55 locomotives still retain "operational status" on the mainline as WAP-1, with further examples having been converted to WAP-4.

Development

Background

In the early 1980s, Indian Railways began considering developing a passenger version of its WAM-4 class... Designed for both passenger and goods trains the WAM-4 was one of the most successful locomotives of the 1970s and a mainstay of the Indian Railways.

Five prototype locomotives of this type were ordered from CLW to the design of RDSO. The first prototype locomotive was put into service in 1981. They were first used on the Howrah Rajdhani Express.

The locomotive is powered by six axle-hungs, nose-suspended forced ventilated type DC traction motors. Speed control is achieved by grouping in 2S-3P combination and by field weakening of the motor. It utilises a silicon rectifier for conversion of AC power into DC.

They are being converted to make them suitable for multiple operations. Compressed air brakes for the locomotives and vacuum brakes for the train are provided. The brake system is being modified to make them suitable for dual brakes.

The WAP-1 provided the basis for the WAP-4.

Variants

The WAP-3 is the upgraded variant of the WAP-1 with better top speed. All units of this class were WAP-1 units already in service. The first locomotive converted was a WAP-1 '22005' named Jawahar. Subsequently 8 more WAP-1 were converted, But since the class were not a great success and had performance issues these were converted back to WAP-1.

Image gallery

Locomotive sheds

Zone Name Shed code Quantity
Northern Railway Alambagh AMV (D) 15
North Eastern Railway Izzatnagar IZN (D) 15
Southern Railway Erode ED (D) 26
Total locomotives active as of December 2023 56


See also