4-6-0 Steam Locomotives in Hungary

Class 327 (Locobase 1561)

Data from A E Durrant The Steam Locomotives of Eastern Europe (Newton Abbot:David & Charles, 1966), pp 29, 40.

Originally procured as a thirteen-simple, two-compound trial batch, the design proved quite successful and 125 more were produced as simple engines in 1913-1914. "Although rather frail in appearance," wrote Durrant,"the 327s are in fact quite powerful engines and have a deep, hefty exhaust to prove it."

After the dissolution of the Austro-Hungarian Empire in 1918, 61 were transferred to Romania, 32 to Yugoslavia, and 22 to Czechoslovakia. 25 remained in Hungary.

Class 328 (Locobase 1562)

Data from A E Durrant The Steam Locomotives of Eastern Europe (Newton Abbot:David & Charles, 1966), pp 30, 40. , supplemented by "4-6-0 Type Locomotive on Hungarian Railways" Locomotive (January 1923).

Brotan-boilered improvement over the already competent 327, these engines had a wider firebox for more steam, larger cylinders, and straight cylinder ports. The Pecz-Rejto feedwater heater was credited with 19.1 sq m (205.6 sq ft ) of surface area.

The steam pipes ran outside the smokebox from the superheater to the cylinders and, Durrant comments, "with the sharply V'd cab and conical smokebox door so typical of Hungary, gave the engines an unmistakeably proud, gaunt, yet rakish air." A[nthony] E[dward] Durrant, The steam loc. Its design goal was to pull 400 trailing tons at 50 mph (80 km/h). Up a 0.7% grade, the engine could haul 470 tons at 31 mph (50 km/h).

Class Ih/320 (Locobase 1554)

Data from A E Durrant The Steam Locomotives of Eastern Europe (Newton Abbot:David & Charles, 1966), pp 25, 40; and "MAV 320 sorozat" in Wikipedia at [], last accessed 4 October 2025. See also P[eter] M[ichael] Kalla-Bishop, Hungarian Railways (Newton Abbot: David & Charles, 1973).

Outside-framed, these powerful Ten-wheeler engines hauled passenger trains in the Transylvania Mountains. Wikipedia criticized the decision to adopt shorter tube lengths in the boiler (possibly to reduce overall wheelbase) as too short to allow efficient use of the thermal energy. (The article concedes the lack of a standard knowledge of the effect of tube length/diameter ratio choices.)

According to Kalla-Bishop, cross-compound 1K Ten-wheelers (Locobase 1555) replaced these engines on their original duty. They soon moved from the Fiume line to the Salgotarjan-Ruttka route and the Vag Valley line

The dissolution of the Austro-Hungarian Empire in 1918 led to the transfer of eight of the nine to Romania (where they had long operated in Transylvania) while only one remained in Hungary.

Class Ik/321 (Locobase 1555)

Data from P[eter] M[ichael] Kalla-Bishop, Hungarian Railways (Newton Abbot: David & Charles, 1973); and A E Durrant The Steam Locomotives of Eastern Europe (Newton Abbot:David & Charles, 1966), pp 29, 40. See also "MAV 321 sorozat" in Wikipedia (translated by Google) at [], last accessed 4 October 2025.

Inside-frame two-cylinder compound that joined the 320 class on the Fiume and Salgotarjan-Ruttka lines. The railway's goal of the design was to upgrade the ability to move high-speed passenger trains "reliably and economically" through the mountains to the port of Fiume. Their small-diameter drivers indicate the predominance of that role in shaping their design.

After tests, MAV settled on a cross-compound cylinder arrangement. Its larger low-pressure cylinder dictated substituting an inside frame as opposed to the tradtional outside frame. "The technical solution was that the main beams of the frame were bent first inwards and then outwards in front of the first coupled axle," Wikipedia explains, "so that after the second bend, the two main beams continued parallel again, but now only at a distance of 810 mm (31 7/8") to the crossbeam." Even after inserting a steel casting to reinforce the frame's resistance as it narrowed, the alternating thrust exerted during a revolution led designers to attach the cylinders to the frame with separate braces.

Further enhancements included increasing the spacing between the leading bogies' axles, repositioning the bogie's pivot 45 mm to the rear, and providing 30 mm of traverse to each side. Leaf springs re-centered the bogie once the locomotive left the curve.

Results showed improvements over the simple-expansion 1h design (Locobase 1554) as the 1ks used less coal and less water. According to Wikipedia, slide valve friction imposed a penalty on power production that soon led to the adoption of piston valves and Ricour drifting valves.

Distribution of assets after the dissolution of the Austro-Hungarian Empire in 1918 led to transfers of fifteen locomotives to Romania while only three remained in Hungary. Remarkably, of those three 31.010 remained in service for almost 70 years before its retirement in 1963.

Class Vauclain compound (Locobase 10372)

Data from "Hungarian State Railways," Railway Notes, The Locomotive Magazine, Vol IX (19 September 1903)., p.174.

Almost all Vauclain compound locomotives were built by the Baldwin company in Philadelphia - their distinctive feature was the arrangement of all four cylinders "in battery", as some commentators have described a 4-abreast layout, and, more important, the use of a single valve to supply live steam to the HP cylinder and that cylinder's exhaust to the adjacent LP cylinder. The system could admit live steam to all 4 cylinders for starting power.

The locomotive in this entry was produced in Hungary with a large grate to burn "brown" (i.e., low-calorie) coal. Its compounding ratio was way out of kilter compared to most compounding setups - which usually fell well above 2:1 -- and gave the LP cylinder too much steam for it to usefully handle.