Indian locomotive class WDS-6


The Indian locomotive class WDS-6 is a diesel–electric locomotive used by the Indian Railways mainly for shunting and also for performing departmental duties. The model name stands for broad gauge, Diesel, Shunting engine, 6th generation. As of April 2022, 375 units of this class are currently in use all over India.

History

This class was designed in 1975 to address the need for a powerful shunting locomotive with the ability to haul 20- to 24-coach rakes. The previous WDS-4 class was found to be grossly underpowered for this kind of operation. A WDS-6 locomotive basically consists of a YDM-4 powerpack mounted on a WDM-2 body frame.
Beginning in 1975, these were initially manufactured solely by BLW, Varanasi, but later, the Parel Workshop started building them using CKD kits provided by DLW.
WDS-6 units can be easily recognized by their low short hoods and flat-ended cabs on the long-hood end. Many of them were sold and transferred to private industrial concerns and public sector undertakings in huge numbers, but still display their IR road numbers.

Locomotive sheds

Total Locomotives active as of March 2025 : 270

Liveries

Generally, these locomotives are seen with the typical yellow livery with green/red stripes.

Technical specifications

The technical specifications of WDS-6 are as follows:
ManufacturersDLW, Parel Workshop
EngineAlco 251-D, Inline-6, with Alco turbocharged engine. 1,100 rpm max, 400 rpm idle; bore x stroke; compression ratio 12.5:1.
TransmissionElectric, DC-DC
Traction motorsGE for original Alco and MLW models, BHEL for DLW
Axle load
total weight
BogiesAlco design cast frame trimount bogies
Starting TE, at adhesion 27%
Length over buffer beams
Distance between bogies