One of the most challenging routes for CFR was definitely the Bucharest to Brasov route and in particular the Campina - Predeal - Brasov section. Crossing the Carpathian mountains, the 75 km section has high gradients (required to reach the Predeal train station at just over 1000m - the highest railway station in Romania), many tight curves and is heavily used by domestic and long distance international traffic. In the days of steam operations usually 2 locomotives were required at the front of the train and 1 or 2 pushers at the rear, a costly operation in terms of manpower and equipment. Plans to double track the route, electrify the route or modernise alternate routes were all discarded due to the high costs involved, leaving the possibility of dieselisation as the only viable alternative to increase efficiency.
Specifications called for unassisted operation of 600 ton trains over the mountainous route, with the ability to restart a train on the steepest grade. This suggested an engine output of at least 4,000hp which, coupled to a 20 ton axle loading requirement and a maximum of eight driving axles, meant building a locomotive of two parts.
The order is placed with SULZER A.G. (Winterthur) as the main contractor. The mechanical parts were provided by Henschel & Sohn AG (Kassel) and the Brown Boveri & Co. workshops at Munchenstein (Basel) managed the electrical parts and engine assembly.
The finished locomotive had a 2-Do-1 + 1-Do-2 wheel arrangement and was powered by two 2,200hp Sulzer engines similar to those fitted in the French PLM double locomotives. It had a maximum speed of 100 km/h, a maximum traction force of 36 tf (353 kN) and weighed 230 tons loaded (218 tons empty) and an axle loading of 19 tons.
The locomotive had the following characteristics:
- power: 2 x 2200 hp = 4400 hp (2 x 1618 kW = 3236 kW);
- powered wheel diameter: 1350 mm;
- free wheel diameter: 1000 mm;
- the length of the locomotive between pads: 29300 mm;
- the weight of the locomotive in service: 230 t;
- own weight (empty): 218 t;
- adherent weight: 148 t;
- maximum axle load: 19 t / axle;
- maximum traction force: 36 t (353 kN);
- maximum speed: 100 km / h.
As constructed the two halves were identical but could not operate as individual units due to the absence of buffers and standard coupling gear on the inner ends. With the intent to purchase more of this type it was considered important that interchangeability of the separate halves be maintained as far as possible (unfortunately the arrival of World War II canceled plans for further orders).
The locomotive was not equipped with any train heating equipment, in cold whether the CFR would allocate a steam heating wagon for passenger trains pulled by this locomotive.
Trial runs take place in Switzerland between Winterthur & St Gallen. The route from Winterthur to St Galle it about 57.5 km long, mostly up hill with grades of 1 in 100 & 1 in 125, the steepest grade being 1 in 83 for 3km between Gruze & Raterschen. With a trailing load of 300 tons the 57.5 km were completed in 45 minutes, with top speeds of 100 km/h.
After over 1.700 km in trial runs, the locomotive is handed over to CFR.
Testing begins on the Bucharest to Brasov route. The testing is so successful that only after 8 days the locomotives is accepted by the railway authorities.
The locomotive enters regular service.
By the end of August, the locomotive had run over 15.000 km. Daily round trips were made between Bucharest and Brassov with a fast train weighing 500 to 600 tons. These trains made frequent stops providing a greater test of the locomotives abilities. The combined fuel capacity of 8,000 litres allowed for two round trips before refuelling and since the locomotive required no assistance on the mountain grades, a considerable number of steam locomotives and their crews could be eventually re-allocated elsewhere. In the early days the locomotive was stopped for one day a week for inspection and the ability to make minor repairs if necessary.
During World War II the double locomotive was stationed at Grivita workshops. When the railway station and workshops were bombed during 1944, the local power supply was disrupted and one of the double locomotives was used as an emergency power supply.
From 1946 - 1963 the locomotive was allocated to Brasov depot.
The locomotive is withdrawn from service and placed on display at Bucuresti Calatori depot.
The locomotive is restored.
The locomotive is moved to Dej Triaj depot.
Latest update on the 3rd of July 2019 at 21:51
Contributor(s): Tudor C.