MÁV Class 601
The MÁV class 601 (nicknamed as "The Giant" or "Big boy" ) was a class of Hungarian four-cylinder Mallet locomotives, which was designed to haul long and very heavy cargo on very steep railway tracks.[1] At 22.5 m (73 ft 10 in) long and outputting 2,200 kW (3,000 hp),[2] they were the largest and most powerful steam locomotives built in Europe before and during World War I.[3] Based on the good operating experience with the series 651, more powerful locomotives arose at the MÁVAG in Budapest from 1914 on, which were especially provided for the line from Karlstadt (today: Karlovac, Croatia) to Fiume (today: Rijeka). By utilisation of the permitted axial load of 16.5 t (16.2 long tons; 18.2 short tons) a locomotive was developed, which alone could move freight trains uphill even on the steep line in the Croatian karst without a banking engine.
Frame and chassisThe required traction power required a very large boiler, so an additional running wheel was placed in front of the six coupled bikes. The coupled bikes were therefore mounted in triplicate in a separate frame in accordance with the Mallet system, while the running wheel was mounted in the front frame as an Adams-Webb type axle with a lateral offset of 42–42 mm. In addition, the rear (driving) wheel of the front frame (i.e. the locomotive's fourth wheel) was turned thinner, and the front (locomotive's fifth) wheel of the rear frame was allowed to move laterally by 12–12 mm. The driven axles were made of 3% nickel steel, while the coupled and running axles were made of liquid steel. The axles of driven and coupled bicycles were completely drilled along the axle line. The suspension of the driven wheels, which were riveted together from 28 mm thick solid iron plates and embedded in an internally arranged frame, was connected by dowels. The first, second and fifth wheels were also fitted with tyre lubricators. The two parts of the frame were connected by the so-called Mallet pin. The complete boiler was mounted on the rear frame - the rear frame extended forward over the front frame to support the front of the boiler - and the cab (in the parlance of the time, the 'locomotive galley'). The extension of the rear frame section rested on the front frame section via a sliding plate. The front frame section could pivot laterally around the Mallet pin, and the straightening and 'anti-snaking' was provided by plate springs. Wheel arrangement (Jelleg): (1'C)'C–h4v Service mass with tender : 163.32 / 162.5 metric tons Total wheelbase with tender : 19,182 mm EngineThe rear frame wheels were driven by high-pressure cylinders and the front by low-pressure cylinders. The steam from the high-pressure cylinders was discharged through the cross-flow tube into the common flow tube, which also served as a receiver, and was fitted with a ball joint at the rear. From the transfer hose, the steam was discharged into the piston chambers of the low pressure cylinders. In each frame, the rear of the nickel-steel rims was the actuator. The right-hand cranks were wedged 90° forward on the wheel axle compared to the left-hand cranks. The piston rod was not a through rod on the rear, only on the front. The piston rod sleeves at the rear of each machine had a Schmidt-type metal seal, while the front of the front machine had a closed bushing. The crossheads were two-wire. The drive and coupling rods were of I-shaped cross-section. To reduce the idling work (resistance) of the steam cylinders, an openable pressure compensating switch connecting the front and rear piston areas of the cylinders and, in the first examples, a Ricour valve on the inlet were fitted, and in later examples air valves were fitted to the piston boxes of the high-pressure cylinders. A compression valve was also fitted to all four cylinders to prevent water hammer. The crossheads were two-wire. In order to facilitate starting, the locomotives were also fitted with a starter, identical in principle to the Borries starter but without a non-return valve, to supply fresh steam to all four cylinders. The steam cylinders were equipped with wide, flexible, self-tensioning cylindrical pushrods with internal inlet, controlled by counter-cranking Heusinger-Walschaert-type camshafts. The high-pressure pistons had a 354 mm diameter, 40 mm internal overlap and 7 mm negative external overlap, while the low-pressure pistons had a 430 mm diameter, 39 mm internal overlap and 4 mm negative external overlap. The counter crank was located nearly 90° ahead of the crank in the forward stroke, essentially it was wedged as a leading edge in relation to the crank. In accordance with this and the internal inlet, the swinging arch stone was positioned on the upper part of the swinging arch (coulisse) in the forward direction. This arrangement, common on domestic locomotives of the period, is not an advantageous solution for locomotives running predominantly in forward gear, as it causes faster wear of the swinging arch bedding. The steering drawbar, which moved forward when the locomotive was moving forward, was connected to the main spar behind the high-pressure cylinders via the steering lever. Also connected to this strut, by means of an intermediate connecting rod, was the front control linkage trailing arm. The main spar was also connected to the rear control units by separate tie rods on either side. This latter solution was necessary because the large standing boiler prevented the main beam from being positioned at the rear control units. BoilerThe locomotive's boiler, based on the experience with the types already mentioned, was built with a Brotan-Deffner type water tube boiler and, in keeping with the times, a Schmidt type superheater. The relatively small diameter of the wheels and the high position of the longitudinal boiler made it possible to have a wide standing boiler and thus a wide grate. Due to the height restrictions of the locomotive, the so-called front head consisted of two parallel cylinders, into which the 70 Brotan 85/95 mm pipes, which formed the side of the firebox, ran. At the time of its construction, the steam boilers of MÁV's 601 series locomotives were the largest Brotan boilers in Europe in terms of size and power. The grate consisted of three parts, the first part was hinged. The longitudinal boiler consisted of three belts, the steam dome being located on the first belt and the Pecz-Rejtő feedwater purifiers on the second: two six-cell cylindrical units arranged in parallel under a common casing. The steam dome houses the water separator and the double flat-piston steam regulator with a vertical pusher. The control rod of the structure was routed inside the boiler. The third boiler belt was tapered to connect to the preheaters and the stationary boiler. The boiler was fitted with 188 continuous flues of 46.5/52 mm diameter and a total of 36 continuous flues of 119/127 mm diameter in four rows. The smoke tubes were fitted with superheater elements consisting of 27/34 mm diameter tubes. The American system spark arrestor and the superheater cabinet were installed in the 2892 mm long fume cupboard. The superheating was controlled by means of a superheater protection cabinet and dampers mounted on it, which were moved by a small steam cylinder (the so-called servomotor or automatic). On the first locomotive, the boiler shell was tightly fitted over the Brotan tubes and the front end, so that after the tapered longitudinal boiler tube there was a break in the outer line of the boiler. In later examples, the standing boiler shell was already fitted to the upper arc of the longitudinal boiler and later the first locomotive was also so designed. The boiler was also fitted with three 4″ MÁV-style[4] direct spring-loaded safety valves and a so-called smoke evacuator. The boiler was fed with water bytwo Friedmann class SZ non-intake, 11 mm orifice, so-called "restarting" fresh steam guns. Boiler SpecificationsType of stationary boiler: Brotan–Deffner system, water-tube firebox Height of boiler longitudinal axis above rail crown: 3120 mm Steam pressure: 15 bar Fire Tubes Number: 188 / 176 Inner/outer diameter: 46.5 mm / 52 mm Length: 5600 mm Flue Tubes Number: 52 / 36 Heating Surfaces Grate area: 5.09 / 5.24 m² Radiant heating surface: 23 / 25.7 m² Tube heating surface: 252 / 221 m² Superheater area: 66 / 87.3 m² Performance Effective steam production capacity: 12,750 kg/h Supporting equipmentThe dome-shaped sandbox was placed on the locomotive's smoke box, behind the chimney. The sanding device delivered sand in front of the second, third and fourth wheels. The locomotive was fitted with one Westinghouse-type brake cylinder per frame and was also fitted with a direct-acting regulating brake for use on longer gradients. The brake shoes braked the locomotive's driven wheels from the front, while the running wheels were unbraked as was usual on MÁV locomotives. The brake shoe pressure was almost equal to the traction weight. To ensure safe running on high gradients, the locomotive was also equipped with a Le Chatelier-type back-steam device. The parts in the steam were lubricated by a 10-slot Friedmann LD piston hot parts lubrication pump per frame. In unfavourable adhesion conditions, a compressed air sand blaster was used to apply sand to the coupled rims of the front frame. For sanding the rear wheel set, a second, smaller sand tank was installed at the driver's position. The locomotives were also equipped with an acetylene generator and a Bavarian system of high-pressure steam heating.
Production dataThe first two examples of the Class 601 steam locomotives were completed by 1914. Soon afterward, an additional 18 units were ordered, followed by a further 40. By the end of the war, 57 units of this type had been produced by the MÁVAG Copany for the MÁV (Hungarian State Railways).
From 1918 onward, MÁV reorganized the major overhauls of its locomotives, allocating them not by geographic region but by locomotive type. The Zagreb Workshop was designated for major overhauls of the Class 601 locomotives. After WW IAfter World War I Following the lost World War I, all previously built Class 601 locomotives ended up beyond Hungary’s borders due to the redistribution of railway vehicles. These included locomotives stranded in severed territories, those seized during the Romanian occupation after the fall of the Hungarian Soviet Republic, and those assigned to successor states under the Treaty of Trianon. The distribution of the locomotives was as follows: CFR (Romania): 15 units ČSD (Czechoslovakia): 6 units SHS (Yugoslavia): 36 units RomaniaThe CFR continued operating the locomotives under their original MÁV class designation and road numbers. Their home depots were Petroșani and Brașov. In Romania, the Class 601 locomotives remained the largest and most powerful steam locomotives. They hauled heavy freight trains on steeply graded lines such as Pui–Petroșani and Brașov–Predeal. CzechoslovakiaThe ČSD initially retained the original class and road numbers. After the permanent division of the Austro-Hungarian railway fleet in 1925, a new numbering system was introduced. The locomotives and their tenders were assigned separate designations: locomotives became 636.001–06, and tenders 526.001–06. YugoslaviaAt the JDŽ (Yugoslav Railways), the locomotives were renumbered to 32-001–036 starting in 1933. HungaryPost-Trianon Hungary retained only three locomotives (road numbers 601.058–060), completed in 1920–1921. These were stationed at the Budapest-Ferencváros depot and hauled heavy coal trains from the Felsőgalla coal basin alongside two Class 402 locomotives. A planned renumbering to 601.751–753 in 1926 was never implemented. To reduce significant boiler scale deposits on the lower fire tube sheets, the number of fire tubes was reduced from 180 to 167 during boiler renovations by removing the lower rows. "Repatriated" LocomotivesMÁV’s locomotive fleet, including the Class 601, expanded significantly after the Vienna Awards. Six locomotives were reclaimed from ČSD and one from CFR, all reinstated with their original road numbers. After World War IIFrom the postwar fleet of 10 locomotives, two were returned to CFR. However, locomotive 601.012 (renumbered 601.061) remained with MÁV. By the 1950s, these locomotives were rarely used, mostly sidelined as reserve units or relegated to boiler heating duty until their certificates expired. The last active example operated until 1954. MÁV scrapped its remaining eight Class 601 locomotives in 1958. In Romania, the locomotives served until 1955, with the last unit scrapped at Petroșani depot in 1960. Not a single example of these locomotives has survived for posterity, leaving only photographs to commemorate MÁV’s mightiest steam locomotive series — a class that ranked among the largest in Europe and was affectionately nicknamed the 'Gigant' in its homeland." Further readingsMezei István. Mozdonyok, 1984 (in Hungarian), Móra Könyvkiadó, p. 64. ISBN 963-11376-3-5. Pottyondy Tihamér. A Magyar Kir. Államvasútak 1–C+C jellegű, 601. sorozatú, kompaund, túlhevítős, Mallet-rendszerű mozdonya [The Compound, Superheated, Mallet-System Class 601 1–C+C Steam Locomotives of the Royal Hungarian State Railways], A gőzmozdony [The Steam Locomotive], 1914, Vol. III, No. 2. Lányi Ernő, Lovász István, Mohay László, Szontagh Gáspár, Villányi György (eds.: Dr. Czére Béla, Dr. Vaszkó Ákos). Nagyvasúti vontatójárművek Magyarországon [Railway Traction Vehicles in Hungary]. Budapest: Transport Museum (1985). ISBN 963-552-161-8. Mezei István, Lovas József. MÁV Vontatójármű Album 1868-1993 [MÁV Traction Vehicle Album 1868-1993]. KÖZDOK (1994). ISBN 963-552-289-4. Malatinszky Sándor (ed.: Dr. Kovács László). Vasúti vontató járművek (1900-1914) [Railway Traction Vehicles (1900-1914)], in Magyar vasúttörténet: 1900-tól 1914-ig [Hungarian Railway History: 1900 to 1914] (Vol. 4). Közlekedési Dokumentációs Kft. ISBN 963-552-314-9 (Full series: ISBN 963-552-311-4) (1997). Villányi György. A Magyar Államvasutak vontatójárműveinek jelölési- és pályaszámrendszerei [Numbering Systems of Hungarian State Railways Traction Vehicles], Vasúthistória Évkönyv 1993 [Railway History Yearbook 1993]. Helmut Griebl, Walter Herschmann, Erich Wohllebe. ČSD-Dampflokomotiven Teil 1-2 [ČSD Steam Locomotives Parts 1-2]. Internationales Archiv für Lokomotivgeschichte, Bd. 11. Wien: Verlag Josef Otto Slezak (1969). Radu Bellu. România – locomotive cu abur (1854 – 2003) [Romania – Steam Locomotives (1854–2003)] (2003). Ing. Jindřich Bek, Karel Kvarda, Josef Janata. Atlas lokomotiv Díl 1., Parní Trakce [Locomotive Atlas Vol. 1: Steam Traction]. Praha: Nadas (1970). Tadej Braté. Die Dampflokomotiven Jugoslawiens [The Steam Locomotives of Yugoslavia]. Wien: Verlag Josef Otto Slezak (1971). ISBN 3-900134-01-4.
References
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