Class W1 Specifications:
Locomotive Class: W1
Manufactured Country: Germany
Manufactured Company: THYSSEN HENSCHEL (Kassel West Germany)
Imported Year: 1969
Type of Locomotive: Diesel Hydraulic
Prime Mover: PAXMAN V12 12YJXL
Maximum Power: 1150hp – 1500RPM
Maximum Speed: 80kmph
Axel Arrangement: Bo-Bo
Weight: 60.5 Tons
Colour: Red, Green & a yellow strip
No. of Locomotives Imported: 45
Locomotive Numbers: 630-674
Class W1 loco is similar to another locomotive in Sri Lanka. It’s the M6 Diesel Electric locomotive. Both Class W1 & M6 locomotives were manufactured by the same company. Although these two classes are similar in appearance, they are different technically. Thyssen Henschel has used the DHG-1200 model, a very successful design for this W1 locomotive. Some years back THYSSEN HENSCHEL (West Germany) was divided into different companies. ADtranz Company was born as a result of this & now it’s known as Bombardier. Another part of THYSSEN HENSCHEL was known as Henschel Antriebstechnik & they only build gear boxes & some locomotive spare parts.
This locomotive is special in different facts. This is the first Broad Gauge Diesel Hydraulic locomotive imported to Sri Lanka. A total of 45 Class W1 locomotives were imported & it’s the highest number by any locomotive class in Sri Lanka. When these locomotives arrive Sri Lanka only M1 & M2 was the main Diesel locomotives in service. Most of the other locomotives were Steam Engines. After the arrival of Class W1, almost all Steam locos were removed from the service. Many trains including Udarata Menike & Podi Menike were hauled by W1 for about 10 years since 1969. These locomotives had the ability to run on every railway line except on Kelani Valley line, which was a narrow gauge line those days. The drivers also had a pleasant attitude for this loco because of the less noise & smooth running.
However after about 20 years of service these locomotives got badly decayed. They had a company warranty for 10 years & the manufacturer had stated that the prime mover should be replaced after 10 years. Replacing a prime mover is a very complicated & it cost a huge amount of money. But this procedure didn’t happen. Lack of funds may be a reason for this.
These locomotives were imported to haul short distance services & the prime movers subjected to wearing quickly due to the high RPM (Rotations per Minute) value & due to the accelerations & decelerations happen in considerable time intervals. As a result of this most of these locomotives were withdrawn from service around 1990. No.674 was removed after it clashed with an intercity express train on 3rd December 1996 at Rambukkana. No.663 & No.664 also faced accidents near Galle & Kapuwatte respectively & they too were withdrawn. Some of these withdrawn locomotives are still in Ratmalana Railway Workshop premises & some were scrapped.
Some Class W1s were re-powered using PAXMAN VEGA SE/RP 160 type 1250hp prime movers. However only No.650 & No.657 are in running condition. In 1997 ten more locomotives were re-powered with the help of ADTranz & re-classified them as Class W3. No. 642, 650, 657 were also repaired using old Class S6 engines.
Credits to Gehan Chandika & Nipuna Dodanthenna.