The Indian locomotive class WAM-4 is a class of 25 kV AC electric locomotives that was developed in 1970 by Chittaranjan Locomotive Works for Indian Railways. The model name stands for broad gauge (W), alternating current (A), mixed traffic (M) locomotive, 4th generation (4). They entered service in March 1971. A total of 500 WAM-4 were built at CLW between 1970 and 1983, which made them the most numerous class of mainline electric locomotive till its successor the WAG-5.
Quick Facts WAM-4, Type and origin ...
WAM-4 |
---|
Arakkonam based WAM-4 (now scrapped) heading towards Perambur. |
Type and origin |
---|
Power type | Electric |
---|
Designer | RDSO |
---|
Builder | CLW |
---|
Build date | 1970–1983 |
---|
Total produced |
|
---|
Rebuilder | CLW |
---|
Rebuild date | 1978–1983 to WAG-5 |
---|
Number rebuilt | 53 |
---|
|
Specifications |
---|
Configuration:
| |
---|
• AAR | C-C |
---|
• UIC | Co′Co′ |
---|
• Commonwealth | Co+Co |
---|
Gauge | 5 ft 6 in (1,676 mm) |
---|
Bogies | ALCO Asymmetric cast frame trimount |
---|
Wheel diameter | New: 1,092 mm (3 ft 7 in) Half worn: 1,055 mm (3 ft 5+1⁄2 in) Full worn: 1,016 mm (3 ft 4 in) |
---|
Wheelbase | 2,108 mm (6 ft 11 in) |
---|
Length:
| |
---|
• Over couplers | 19,975 mm (65 ft 6 in) |
---|
• Over body | 18,680 mm (61 ft 3 in) |
---|
Width | 3,055 mm (10 ft 0 in) |
---|
Height | 4,162 mm (13 ft 8 in) |
---|
Frame type | Asymmetric cast frame |
---|
Axle load | 18.8 tonnes (18.5 long tons; 20.7 short tons) |
---|
Loco weight | 112.8 tonnes (111.0 long tons; 124.3 short tons) |
---|
Sandbox cap. | 16 units X 30 t (30 long tons; 33 short tons) |
---|
Power supply | 110 V DC Supply |
---|
Electric system/s | 25 kV 50 Hz AC Overhead |
---|
Current pickup(s) | Pantograph |
---|
Traction motors | Alstom TAO 659A1 |
---|
• Rating 1 hour | 770 HP. 750 V, 840 A, 1095 RPM |
---|
• Continuous | 798 HP. 750 V, 870 A, 1070 RPM |
---|
Head end power | 110 V DC Supply |
---|
Transmission | Electrical |
---|
Gear ratio | 15:62 |
---|
MU working | 4 units |
---|
Loco brake | Air, Rheostatic braking |
---|
Train brakes | Air, Vacuum and Dual |
---|
Safety systems | Slip control, Over voltage relay, No volt relay, Earth fault relay, Low pressure governor, Train parting alarms, and Brake cylinder cutoff valve |
---|
|
Performance figures |
---|
Maximum speed | 120 km/h (75 mph) |
---|
Power output | 3,640 hp (2,710 kW) |
---|
Tractive effort:
| |
---|
• Starting | 33,840 kgf (331.9 kN; 74,600 lbf) |
---|
• 1 hour | 30,000 kgf (290 kN; 66,000 lbf) |
---|
• Continuous | 17,600 kgf (173 kN; 39,000 lbf) |
---|
|
Career |
---|
Operators | Indian Railways |
---|
Class | WAM-4 |
---|
Numbers |
- WAM-4B: 20400–20699, 21200–21399
- WAG-5: 21100-21138
|
---|
Nicknames | Garuda, Ananth, RAJATABHA, Surubhi, Navchetna, Sukh Sagar, Naveen |
---|
Locale | All over India |
---|
Delivered | 4 December 1970 |
---|
First run | March 1971; 53 years ago (1971-03) |
---|
Withdrawn | May 2023; 1 year ago (2023-05) |
---|
Preserved | 6 units |
---|
Disposition | A few units still in inferior service, rest scrapped |
---|
|
Close
The WAM-4 is one of the most successful locomotives of Indian Railways having served both passenger and freight trains for over 52 years. This class provided the basic design for a number of other locomotives like WCAM-1, WAG-5A, WCG-2, and some WAP-1 models. However, with the advent of new 3-phase locomotives like WAP-5 and WAP-7, the WAM-4 locomotives were relegated to hauling smaller passenger trains and most of the units have been scrapped. A few units are in service performing backup and non essential duties.