FCMU No. 20 and 22
| LDE 846 and LDE 847 | |
|---|---|
 |
|
| Axis formula : | C'C ' |
| Type : | Winterthur angled bar |
| Gauge : | 1000 mm ( meter gauge ) |
| Length over buffers: | 14,600 mm |
| Total wheelbase: | 12,800 mm |
| Service mass: | 70 t |
| Top speed: | 60 km / h |
| Installed capacity: | 474 kW |
| Motor type: | diesel |
| Power transmission: | electric |
The locomotives no. 20 and 22 (later LDE 846 and LDE 847 ) of Ferrocarril Machacamarca – Uncía (FCMU) were two so-called diesel crocodiles made by the Swiss manufacturer Sulzer .
History and technology
In order to develop the silver and tin mines in the Bolivian highlands, an approximately 96 km long meter-gauge route from Machacamarca to Uncía was built from 1911 . The single-track railway line went into operation in 1920 and was used for freight and passenger traffic. The line belonged to the Ferrocarril Machacamarca – Uncía (FCMU) railway company . The route began in Machacamarca at an altitude of 3,700 m, crossed the 4,400 m high Paso de Bombo and ended at 3,900 m in Uncía. The maximum gradient of the very winding route was 25 per thousand, the smallest curve radius 70 meters and the permissible axle pressure twelve tons. The maximum permissible speed was 60 km / h.
Extreme climatic conditions prevail at this altitude. The outside temperatures fluctuate between −15 ° C in winter and +30 ° C (in the shade) in summer. In Machacamarca, the FCMU line was connected to the meter-gauge railway line to the Catavi mining center and to Oruro , where there was a connection to the main line to La Paz.
The diesel age began at FCMU in 1933 with the acquisition of two railcars from Germany. In 1939, the FCMU ordered a six-axle, diesel-electric locomotive for freight and passenger transport from the Sulzer brothers in Winterthur as general contractor.
The specifications stipulated the following framework conditions:
- Transport of a train of 250 tons on an average gradient of 20 per thousand in continuous operation.
- Driving the entire route with a 100-ton passenger train in three hours of pure travel time.
- Driving the entire route with a 150-ton freight train in 3.5 hours.
- Driving the entire route with a 250-ton train in 4 hours.
The Sulzer company initially commissioned Henschel & Sohn in Kassel as a supplier. Because of the Second World War, Henschel could not carry out the order. The locomotive was therefore built by Sulzer , MFO (electrical systems) and Les Ateliers Metallurgiques SA , Nivelles (Belgium) and completed in 1949.
The three-part locomotive had the design of a "real crocodile". The locomotive bridge with the locomotive body rested on the two motor bogies with the low front ends.
A six-cylinder four-stroke diesel engine produced a continuous output of 474 kW at 700 rpm at an altitude of 4,000 meters. The diesel engine drove a main and an auxiliary generator. The main generator supplied the energy for an electric traction motor each, which was arranged together with a fan above each bogie in the front end. The drive power was transmitted to the three axles of each bogie with the help of a toothed back gear and the Winterthur helical rod drive.
The motor bogies were very similar to those of the Ge 6/6 I of the RhB. The main generator was also used to start the diesel engine, with the electricity required from two starter batteries. The two batteries were housed in the stems.
The auxiliary generator was responsible for exciting the main generator, charging the batteries, feeding the electric motors for the cooling water pump, the cooling fan, the fans for the traction motors, the brake compressor and the converter, which supplied the electricity for the lighting and control.
The diesel engine was protected against overload and was automatically switched off if the water or lubricating oil pressure was too low or the cooling water temperature was too high.
The locomotive bridge transmitted the tensile and impact forces. As is customary with crocodiles , the locomotive body comprised the two driver's cabs.
The locomotive, which was ordered as number 20 , went through an extensive test program at the RhB. It was delivered to Bolivia in 1952 as number 22 , but had a plate with the number 20 and was later given the company number LDE 846 .
Since the locomotive proved itself well in everyday operation, the FCMU ordered a second locomotive as number 23 . This machine was built by Sulzer , MFO and Krupp (Essen). The locomotive was delivered in 1956 as number 24 , although it had a plate with the number 22 on it. This machine was later redesignated as LDE 847 .
In 1987 the Empresa National de Ferrocariles (ENFE) took over the FCMU. In 1995 the ENFE was split up and partially privatized. From 1996, Empresa Ferroviaria Andina (FCA) operated the approximately 2,260-kilometer-long meter-gauge network in the highlands of Bolivia. The FCA did not take over the two locomotives - which were in service until the 1990s.
The LDE 846 was last seen and photographed in 2008 on the premises of the ENFE / FCA workshop in Oruro. The exterior of the LDE 847 is well restored in the workshop of the Patiño mine in Machacamarca. This workshop has been the Machacamarca Railway Museum since 2009 , in which various railway vehicles document the railway history of Bolivia.
literature
- Hans-Bernhard Schönborn: The crocodiles - locomotive legends - electric locomotives from SBB, ÖBB, RhB and DB , transpress Verlag, Stuttgart, 1st edition 2014, pp. 118–121, ISBN 978-3-613-71482-3
Web links
- Two pairs of Bolivian "Sulzers" (English)