Indian locomotive class WDM-7
diesel-electric locomotive of Indian Railways
The 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.
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.
History
Fifteen of these locomotives (road numbers #11001 to #11015) were built from 1987 to 1989 as a low-powered, “lightweight” version of the original ALCO. Like the WDM-6, the IR wanted a lower powered locomotive to handle small rake local and passenger services. However, all sheds declined them and they ended up at Ernakulam where they were used to handle local and shuttle services with good degrees of efficiency. Becoming aware of their abilities, the Southern Railway moved all the WDM-7s out of Ernakulam to Tondiarpet, where they are housed there as of 2023. These days, they are seen being used as shunters at Chennai Central or for light passenger haulage. One (#11008) has been modified to run on bio-diesel.
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