Magyar Allamvasutak Articulated Locomotives in Hungary

Class 601/636 (Locobase 1580)

Data from A[nthony] E[dward] Durrant, The Steam Locomotives of Eastern Europe (Newton Abbot:David & Charles, 1966); and Gustav Reder (Michael Reynolds, trans), The world of steam locomotives (New York: Putnam, 1974), pl 332. See also [] . For a contemporary description of the Brotan boiler, see E Gobert, "The Brotan Water Tube Fire-box," The Railway Magazine, Volume 21, pp. 41-43. See also "Locomotive Boilers,"American Engineer and Railroad Journal, Volume 84 (October 1910), pp. 421-424; "Hungarian Mallet with Brotan Type Boiler", Railway Age, Volume 77, No 10 (6 September 1924), pp. 407-410.

The latter says the 601s could pull a 2,600-ton (2,240 lb) train at 30 km/h (18.6 mph) on the flat. Reder (1974, pl 332) gives other ratings such as pulling 396 tons up a 2.5% grade at 12.5 mph and 373 tons up the same grade at 25 mph. HP piston valves measured 250 mm/9.84"; LP piston valves 340 mm/13.39:.

The design used a Brotan firebox, which Gustav Reder claimed, was the only design significantly different from the Stephenson type to have been successful. The Brotan (after Johann Brotan, works foreman at Austrian State Railroads' Gmund headquarters) used a combustion chamber formed out of tubes that were gathered together in a steam drum overhead. The tubes also extended underneath to form the foundation ring.

The physical result was unmistakeable. A narrow cylinder was mounted along the centerline over the firebox and joined to a larger-diameter cylinder over the boiler section. The upper boiler was supported on the lower boiler by three large pipes that allowed steam to circulate in both sections. The upper half collected the steam chamber and had the steam and sand domes riding on it.

Sixty of this class ran on Hungarian rails (Tufnell (1986) says 90), three were delivered to Turkish Eastern Railways. See Wiener (1930) for slightly different LP cylinder dimensions.

After World War I, 36 were taken into Yugoslavian service, 15 went to Romania's CFR, and 6 wound up as Czech class 636

---

Class Category IVd/422 (Locobase 1576)

Data from Data from Gustav Reder (Michael Reynolds, trans), The World of Steam Locomotives (New York: Putnam, 1974); A[nthony] E[dward] Durrant, The Steam Locomotives of Eastern Europe (Newton Abbot:David & Charles, 1966);, and Lionel Wiener (1930).

Mallet operated between Fiume and Karlstadt (Austro-Hungarian Empire) that was rated at 394 tons up a 1.67% grade at 10 mph. Some of these engines also operated in the Carpathian coal regions between Piski and Petroseny. Reder (1974)

A[nthony] E[dward] Durrant, The steam loc; Wiener (1930). According to Josef Poschipal's Austro-Hungary and beyond website (it's really quite an undertaking) -- [], last accessed 3 August 2006 -- the class was delivered quickly. The first four -- works numbers were 1342-1345 in 1898. 1494-1499 came in 1900, 1566-1675 in 1901, and 1641-1650 in 1902. (They were numbered consecutively 4401-4430.)

Janos Ero, in an article Google-translated as "Mallet Locomotives in Hungary" on [] ...(11 November 2004; link later inactive), noted that this Mallet design offered some challenges. Drivers had to learn to cope with the front driver set's tendency to slip on starting. Ultimately, the design was a success in that its compound working resulted in more power for the grade. They were capable of higher speeds than the 0-8-0s that preceded them, achieving 50 km/h (31 mph).

---

Class VIm/ 651/ 623.0 (Locobase 1581)

Data from Gustav Reder (Michael Reynolds, trans), The World of Steam Locomotives (New York: Putnam, 1974) and from Wiener (1930). See also "Mallet Type Locomotive Kassa Oderberg Railway, Austro-Hungary", Locomotive Magazine, Volume 19 (14 June 1913), pp. 120-121.

Because the Petroseny-Lupeny section of Hungarian railroading in the Carpathian Mountains was laid with rail that limited axle loading to 16 long tons (16,257 kg or 35,840 lb), these engines were produced with six driving axles to spread out the weight and increase available adhesion. They were rated at 508 tons up a 1.5% grade at 12.5 mph. In addition to the 58 on the Hungarian State, the Kassa-Odebergi Railroad received another 24. In addition, thirteen more fitted with Brotan boilers (a boiler design described in more detail in Locobase 1580) entered service shortly thereafter.

Durrant 1966 says the axle loading on these engines was 26,887 lb (12,200 kg).