Short history of the MÁV Class 327 steam locomotives

Predecessors

The Hungarian railways were in lack of powerful and speedy fast train locomotives. After founding MÁV in 1868 the Class I. which was foreseen for fast train locos, was an empty Class. The first Class I. machines purchased from Austria were weak and hard to maintain. The first locos designed directly for MÁV service were the later Class 220 units were also poorly suited for the needs. When they appeared they were rather heavy, thus a lighter version was designed, the later Class 221. This was, however, rather error prone and thus shortly later, when the track maintenance allowed, the heavier Class 220 was purchased again. In parallel with these locos a new, much more powerful Class was developed, the larger Woolf-tandem Class 222. This was a successful construction but its complex tandem machine was expensive to build and difficult to maintain. Thus in the last years of the 19th century both Classes were purchased in parallel.

In the year 1900 the Hungarian Locomotive manufacturer MÁVAG designed a new, modern, high boilered locomotive, the Class 201 Atlantic and her compaund engine sister, the Class 202. Long trials followed with these new locos but it turned out, due to their relatively small boiler they were not basically more powerful than the earlier Class 222. No series production followed the prototypes.

A new high powered Atlantic was designed instead, the later Class 203. The members of this Class were powerful enough, but due to the 4-4-2 arrangement these engines had limited traction force to haul heavy Pullmann-type cars. Thus MÁV cancelled the order after putting 24 engines in service and required a new, even more powerful design with 4-6-2 Pacific arrangement.

This was the Class 301, a strong four cylinder DeGlehn machine with large size boiler. She could perform all tasks the Railway wanted. Her heavy axle load, however, limited her application to the two most important mainlines of Hungary.

The Class 327

Design

In order to offer high speed service on lighter mainlines, a lighter Class has been designed. To offer sufficient traction force this was designed as a Ten-Wheeler, 4-6-0. The construction used many components designed for other existing locos. The wheelsets are similar to the Class 301 wheels. The boiler is lighter, shorter and of course superheated. As most fast train locos at MÁV the smokebox door had conical shape to decrease wind resistance and even the cab corners were chamfered. The loco was equipped with all tools usual that time, like water cleaner on the boiler top, a Friedmann central lubricator and Haushälter-type recording speedometer.

The main rod drives the first drivers. This results in increased vertical forces on the crosshead guides and later on the maintenance observed ruptures on the mainframe behind the cylinder block. This was corrected by riveting a vertival triangular steel plate there.

A new tender was also designed for these machines. Its base and trucks are the same as the tender of the Class 301, but it can contain more coal and less water. Probably it was considered these light engines stop more often when they can take water.

Manufacturing

As first step four prototype engines were constructed. The locos 327,001 and 327,002 were built with superheated twin engines the 327,501 and 327,502 were superheated two cylinder compounds. These participated in trials in order to find out if the compound technology has benefits using superheated steam. The tests were rather short, the prototypes were built in April 1912 but in November of the same year the series production already started. Probably the earlier similar tests with the Class 301 were enough to make the decisions to build only superheated twins. Although the compound engines' coal and water consumption was lower than those of the twin engines, the purchasing and maintenance costs were considerably higher. In addition the tests showed the benefits of the compound system were mostly visible at lower speeds, at high speed the differences were negligable. Thus for a loco designed for fast trains it made little sense to use the more complicated compound machine.

136 engines of the series production were manufactured in a rather short time. In August 1914 the last engine of this Class entered into service. Of course MÁVAG manufactured locos for other Classes too, total 546 locomotives were finished during these 22 months. If we do not count the Sundays - that era full time job was done on Saturdays - these machines were delivered in 560 consecutive working days. In general one locomotive every day.

Subtypes and Versions

During the short manufacturing period only few modifications were applied to the Class. The manufacturer's type number 102.01 was given to the prototypes. The series production was made from types 102.02 to 102.04. Watching the photos we can find a few differences between the early and late locomotives. The early engines were equipped with balanced spring type security valves the late ones with pop-valves The pictures of the first locos show a reverse rod with one support the new ones with two supports on the boiler side. The early locomotives were equipped with a single stage Westinghouse air-pump without cooling ribs the new ones have a two-stage, ribbed pump.

These are small differences but good candidates to build two slightly different models.

Later modifications

The Class 327 soon overtook all light fast trains pushing the Class 222 to less demanding servica. The maintenance, however, observed starting cracks on the mainframe behind the cylinder block fixations. The probable reason was the short main rod that forwarded strong vertical forces. To fix the problem triangular steel sheets were riveted behind the cylinder block. The later machines were already built with this sheet, the first ones were equipped in the repair shop.

Class 327 in service

During the WW1 the Class 327 performed well. In order to fulfill the increasing transport requirements further fast train locomotives were needed. Due to the copper shortage the new locomotives should have been built with all-steel Brotan boiler. Besides of this the construction was also changed, in order to avoid vertical forces on the mainframe the new design showed a loco with longer main rod driving the second driver, rather than the first one. This designe became a new Class, the 328.

After the WW1 the Romanian Army occupied East-Hungary and took away 61 locomotives of the Class, these became members of the Romanian CFR fleet. For long time the Romanian fast train service was based on these locomotives. Czechoslovakia and Yugoslavia got 22 and 32 engines respectively, only 25 pieces of the original 140 remained in Hungary. They performed the same service tasks as their successors, the Class 328 locos.

During the WW2 several Class 327s returned to Hungary from the neighbouring countries and the 327 was one of the few locomotive Classes counting more members after WW2 than before.

The Class 327 remained in active service until the mid 1960s. Most of them were withdrawn and scrapped between 1964 and 1966, a few examples remained active until 1969.

Only one single Class 327, the 327,141 (originally 327,016) survived. She was used as steam boiler on wheels, thus her cylinder blocks and rods were removed and scrapped. Today she is in the big hall of the museum locomotive repair shop in Istvántelke, but her future is still uncertain.

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