Class W3

Class W3 659 at Gampaha

Class W3 Specifications:

Locomotive Class: W2

Re-powered Country: Sri Lanka

Re-powered Company: ADtranz

Imported Year: 1997

Type of Locomotive: Diesel Hydraulic

Locomotive Design: DH3-1200

Prime Mover: Caterpillar V12 3512 DI-TA 4 Stroke

Maximum Power: 1200hp – 1500RPM

Maximum Speed: 80kmph

Axel Arrangement: Bo-Bo

Weight: 64 Tons

Length: 12.8m

Colour: Blue, Silver & a Yellow colour strip

No. of Locomotives Re-powered: 10

Locomotive Numbers: 631, 636, 638, 647, 659, 665, 666, 667, 669, 673

The lifetime of Class W1 locomotives were limited to 20 years. Although these W1 locomotives was left alone, a project was proposed by SLR to re-power 10 of these locomotives. At the beginning locomotives numbered 636, 638, 645, 647, 648, 649, 661, 662, 663 & 679 were proposed to re-power but these locomotives were removed from the list & 10 other locomotives including No. 631, 636, 638, 647, 659, 665, 666, 667, 669 & 673 were selected finally.

M5 locomotives also were re-powered by a project like this & it was categorized into M5 sub classes as M5a, M5b & M5c because it was a Sri Lankan project. But this project was done on a contract with a foreign company. Therefore repowered W1 locomotives were added to a new class called Class W3. This company was the ADTranz who bought the Henshel Company which made W1 locos. Ten Caterpillar 3512 DI-TA engine sets were used for this project. This project was completely done under the grants of Netherlands government & United Tractors Limited acted as the local agent.

Under this project Prime Movers & Power Transmission Units which were in W1 locomotives were replaced by new equipment & the functioning of the locomotive was shifted to a new Electronic control system from old Mechanical control system. Therefore most of the functions of this W3 locomotive is controlled by the electronic system (But not as complex as the system in Alstom Prima, Class M9 loco). Some external features also were re-designed in this project & the RPM (Rotations per Minute) value (1800RPM) of the new Caterpillar engine was reduced to 1500RPM to reduce wearing.

W3 was designed to attach two or more locomotives (Multiple Units). And the driver can control all locomotives from a single cab when using these locos Double Headed (2 locomotives attached together). Hydro Dynamic Brakes was added to W3s which was not included in W1 locomotives. This locomotives were fitted Air brakes & Vacuum brakes to haul any type of carriage & W3 is the only diesel hydraulic locomotive which is capable of hauling Chinese carriages.

This locomotive can run on every railway line. A W3 loco is used to haul many Hatton bound express trains such as Tikiri Menike. Apart from it this loco is used to haul Galle-Colombo, Colombo-Polgahawela, Chilaw, Panadura & Aluthgama trains & for service trains & breakdown trains.

The noise of this locomotive is slightly higher than W1 locomotives. And it’s said that the lifetime of this locomotives are going to be end. Warranty period of W3s were 10 years since re-powering. Therefore respective companies had stated that the major repairs of these locomotives should be done in 2008. However 9 of the 10 W3 locomotives are still in service. No.636 was withdrawn due to a defect in prime mover armature.

Credits to Gehan Chandika & Nipuna Dodanthenna.