Indian locomotive class WDM-7

Indian locomotive class WDM-7
WDM-7 hauling a freight, the loco is running on bio-diesel
Type and origin Power type diesel Builder BLW Model DL560C Build date 1987- 1989 Total produced 15
Specifications Configuration: ​  • UIC Co′Co′  • Commonwealth Co-Co Gauge 1,676 mm (5 ft 6 in) Bogies ALCO Asymmetric cast frame trimount Wheel diameter 1,092 mm (3 ft 7 in) Wheelbase 12.834 m (42 ft 1+1⁄4 in) Length 17.12 m (56 ft 2 in) Width 2.864 m (9 ft 4+3⁄4 in) Height 4.185 m (13 ft 8+3⁄4 in) Axle load 17,800 kg (39,200 lb) Loco weight 96,000 kg (212,000 lb) Fuel type diesel Fuel capacity 5,000 L (1,100 imp gal; 1,300 US gal) Prime mover ALCO 251-B RPM range 400–1000 rpm Engine type V12 diesel Traction motors BHEL 4906 BZ and 4907 AZ Cylinders 12 Cylinder size 228 mm × 266 mm (8.98 in × 10.47 in) bore×stroke Transmission Diesel-electric transmission MU working 2 units Train brakes Air, Vacuum and Dual
Performance figures Maximum speed 105 km/h (65 mph) Power output Max:2,000 hp (1,500 kW) Site rated:1,800 hp (1,300 kW) Tractive effort 25.3 t (25 long tons; 28 short tons)
Career Operators Indian Railways Numbers 11001-11015 Locale SR Disposition active

The class WDM-7 is a diesel-electric locomotive of Indian Railways. It has been manufactured by Banaras Locomotive Works (BLW), Varanasi. The model name stands for broad gauge (W), diesel (D), mixed traffic (M) engine. The WDM-7 are found exclusively at Chennai Central and nearby area.

These units have been retro-fitted with air brakes, in addition to the original vacuum brakes. The WDM-7 locos have a maximum speed of 105 km/h (65 mph), restricted to 100 km/h (62 mph) when run long hood forward - the gear ratio is 94:17.

TNP WDM-7 resting in siding

History

These locos were built from 1987 to 1989. A few were at Ernakulam earlier but later all were transferred to Tondiarpet seen being used as shunters at Chennai Central or for light passenger haulage. Some are at the thermal power station, Chennai.

These Co-Co diesel-electrics were designed for branch-line duties (top speed 105 km/h). They have two 3-axle bogies and are similar to the WDM-2 in appearance. The power-pack is a 12-cylinder Alco 251B unit. They are lower powered version of the WDM-2. They were formerly housed at Erode and Golden Rock also. They are reliable and rugged locomotives even though low powered. They can be easily recognised by the lack of grilles on the short hood. Two locos are running on a mixture of bio-diesel and diesel. All 15 are still in service.

Locomotive shed

Zone	Nmae	Shed Code	Quantity
Southern Railway	Tondiarpet	TNP	15
Total Locomotives Active as of July 2020			15

Former

• Ernakulam
• Erode
• Golden Rock

See also

• Indian locomotive class WDM-2
• List of diesel locomotives of India]
• Rail transport in India
• History of rail transport in India

External links

• Ministry of Railways (Railway Board)
• [IRFCA] Indian Railways Locomotive Roster Changes