The necessity

After independence  there was a phenomenal Increase in Railway traffic in India. To cope up the demand it was felt necessary to modernise the Indian Railways with faster trains . Steam locomotive had a draw back in their capacity and speed.  The ministry of Railways decided to set up manufacture of Diesel Locomotives at Varanasi and Electric Locomotives at Chittaranjan for main line use. The problem for main line having been solved to some extent, there was still difficulties in shunting locomotives and shuttle services . There was also demand for better haulage in Metropolitan towns, Colliery sidings and other large public sector plants and  areas like ports, cement factories , Steel, fertiliser etc. which were done old steam locomotives. This work was trusted on Chittaranjan Locomotive Works. A completely new phase of work was started in 1966 and the first Diesel shunter  650 H.P. WDS 4 with 48% indigenous content, was commissioned by Shri C.M.Poonacha , the then Railway Minister on 5th January,  1968. 

These Locomotives were manufactured in collaboration with MaK of the then West Germany and are fitted with SURI transmission . These locomotives are in service in different Railways in India and a large number of Public Sector Units. 

These Diesel shunters are of rugged design having three axles, a rigid frame, Jack-shaft and coupling rod drive, a well proven design in German federal Railways and also in India.

SALIENT FEATURES

Transmission
Suri Hydro-mechanical transmission with optional change over to mechanical transmission at 40% maximum road speed, and automatic change over at 70% of max. road speed.

Reversing Gear Box
This provides for forward and reverse directions as also choice of shunting and main line speed range gears for either direction

Mechanism of Work

The power from engine is transmitted to wheels through a cardan shaft, then  the transmission and finally through a drive gear box where the final output is connected to the wheels by coupling rods. 
It has six wheels out side  the main  frame plates. The wheels are connected with each other and the output shaft of the gear box through coupling rods. Seems similar to steam locomotive practices.

The Driver's cab , a raised one is placed in middle between front and rear superstructure. Large windows provided in rear and front and also sides. This gives the driver to have a clear view of all sides. The controls are placed in a desk within the reach of the driver. The front Superstructure houses the engine, compressor, vacuum exhauster , the fuel tank and the control equipments. The rear part houses the final drive gear box the transmission, its oil tank and the radiator . The radiators fans are a little different . These are driven by hydrostatic motors instead of mechanical or electrical drive, being adjusted by governors to suit different ranges of cooling requirement.   

ADVANTAGES

1. Saving in operating expenses as compared to Steam Locomotives.

2. Quick acceleration and improved hauling capacity. 

3. More suitable for negotiating  sharper curves. 

4. Due to efficient and quick working the line capacity is increased for hauling more  traffic.

5. Elimination of smoke and coal grit nuisance.

The production of Diesel Hydraulic Locomotives was taken up during 1968. After manufacturing  842 Diesel Hydraulic Locos of 7 types, production of diesel hydraulic locos were discontinued from  1993-94 .

Please visit other pages