Saxon XV HTV
Encyclopedia
The Saxon Class XV 
T
was a class of goods train steam locomotive operated by the Royal Saxon State Railways
, which had been conceived for hauling trains and acting as banking engines for routes in the Ore Mountains. In 1925 the Deutsche Reichsbahn
grouped them into their DRG Class 79.0.
, formerly Hartmann.
The undercarriage of the locomotives was unusual. Instead of an alternative proposal for a twelve-coupled locomotive with sideways-sliding Gölsdorf axle
s, as was realised a year later in the shape of the Württemberg K
, the Saxon Railways decided on a proposal by their head of the engineering department, Lindner, for a design that was unique in Germany: the Saxon XV HTV was given two, fixed, six-coupled drives. This was mainly because they had doubts about the suitability of the Gölsdorf system for twelve-couplers. The outside axles were designed as Klien-Lindner axle
s and could be slid sideways by about 37 mm from their centre position. The design of these axles required them to be fixed into an outside frame
. In the centre of the locomotive was a double cylinder each with a high-pressure cylinder for the rear and a low-pressure cylinder for the front drive.
This design with its low stress on the rails, low inherent resistance and simple weight compensation was promising especially as it also avoided the use of cranked driving axles. Similar thoughts in the USA during the 1930s led to the development of duplex locomotive
s. Because the cylinders of adjacent axles also had 28 mm of side play, the locomotive could negotiate radii of as little as 170 m. Through the special design of the cylinders the use of crank axles (Kropfachse). Whilst this design enabled the steam lines between the high- and low-pressure cylinders to be extremely short, long admission and exhaust tubes were necessary.
The XV HTV soon proved to be expensive to maintain, particularly with regard to the drives and the hollow axles; as a result no more were procured. Even the usual tendency of all compound engines to sway could not be eliminated by the Klien-Lindner configuration. Wear and tear on the wheel tyres changed the crank settings of the driving gear. That meant that the synchronisation of the drive had to be constantly adjusted, in order to ensure a balanced distribution of effort.
Nevertheless the engines were successful in practice. They had impressive riding qualities right up to their top speed and wear and tear on the wheel flanges was low. The Deutsche Reichsbahn
took both locomotives over as 79 001 and 79 002, but retired them by 1932.
The serial number 79 001 was allocated from 1938 to 1947 to BLE No. 44
of the former Brunswick State Railway Company
and from 1951 it was given to the former French locomotive, 242 TA - 602, which ended up in German hands after World War II
.
barrel comprised 2 shells with a diameter of 1,450 mm. On the top were two steam domes which were connected by a pipe inside the boiler. Between steam dome and chimney was a sand box. The firebox was made of copper and position over the first axle of the rear drive. The smokebox
superheater
was of the Schmidt type.
The locomotive frame
comprised an inside frame of 28 mm thick plate, and an outside frame for the hollow axles of 20 mm thick plate.
The four-cylinder compound engines were arranged horizontally on the outside and each drove its centre axle
T was a class of goods train steam locomotive operated by the Royal Saxon State RailwaysRoyal Saxon State Railways
The Royal Saxon State Railways were the state-owned railways operating in the Kingdom of Saxony from 1869 to 1918...
, which had been conceived for hauling trains and acting as banking engines for routes in the Ore Mountains. In 1925 the Deutsche Reichsbahn
Deutsche Reichsbahn
Deutsche Reichsbahn was the name of the following two companies:* Deutsche Reichsbahn, the German Imperial Railways during the Weimar Republic, the Third Reich and the immediate aftermath...
grouped them into their DRG Class 79.0.
History
The two locomotives were built in 1916 at the Sächsischen MaschinenfabrikSächsische Maschinenfabrik
The Sächsische Maschinenfabrik in Chemnitz was one of the most important engineering companies in Saxony in the second half of the 19th century and the first two decades of the 20th century. Including its various predecessor businesses, the firm existed from 1837 until its liquidation in 1930, and...
, formerly Hartmann.
The undercarriage of the locomotives was unusual. Instead of an alternative proposal for a twelve-coupled locomotive with sideways-sliding Gölsdorf axle
Gölsdorf axle
The Gölsdorf axle system is used on railway locomotives to achieve quiet running and low wear-and-tear when negotiating curves. It comprises a combination of fixed axles and axles that can slide radially, all within a single, rigid locomotive frame....
s, as was realised a year later in the shape of the Württemberg K
Württemberg K
The Württemberg Class K steam locomotives of the Royal Württemberg State Railways were the only twelve-coupled locomotives built for a German railway company.-History:...
, the Saxon Railways decided on a proposal by their head of the engineering department, Lindner, for a design that was unique in Germany: the Saxon XV HTV was given two, fixed, six-coupled drives. This was mainly because they had doubts about the suitability of the Gölsdorf system for twelve-couplers. The outside axles were designed as Klien-Lindner axle
Klien-Lindner axle
The Klien-Lindner axle is a special type of hollow driving axle on steam locomotives that enable better curve running due to its ability to slide transversely...
s and could be slid sideways by about 37 mm from their centre position. The design of these axles required them to be fixed into an outside frame
Locomotive frame
A locomotive frame is the structure that forms the backbone of the railway locomotive, giving it strength and supporting the superstructure elements such as a cab, boiler or bodywork. The vast majority of locomotives have had a frame structure of some kind...
. In the centre of the locomotive was a double cylinder each with a high-pressure cylinder for the rear and a low-pressure cylinder for the front drive.
This design with its low stress on the rails, low inherent resistance and simple weight compensation was promising especially as it also avoided the use of cranked driving axles. Similar thoughts in the USA during the 1930s led to the development of duplex locomotive
Duplex locomotive
A duplex locomotive is a steam locomotive that divides the driving force on its wheels by using two pairs of cylinders rigidly mounted to a single locomotive frame; it is not an articulated locomotive...
s. Because the cylinders of adjacent axles also had 28 mm of side play, the locomotive could negotiate radii of as little as 170 m. Through the special design of the cylinders the use of crank axles (Kropfachse). Whilst this design enabled the steam lines between the high- and low-pressure cylinders to be extremely short, long admission and exhaust tubes were necessary.
The XV HTV soon proved to be expensive to maintain, particularly with regard to the drives and the hollow axles; as a result no more were procured. Even the usual tendency of all compound engines to sway could not be eliminated by the Klien-Lindner configuration. Wear and tear on the wheel tyres changed the crank settings of the driving gear. That meant that the synchronisation of the drive had to be constantly adjusted, in order to ensure a balanced distribution of effort.
Nevertheless the engines were successful in practice. They had impressive riding qualities right up to their top speed and wear and tear on the wheel flanges was low. The Deutsche Reichsbahn
Deutsche Reichsbahn
Deutsche Reichsbahn was the name of the following two companies:* Deutsche Reichsbahn, the German Imperial Railways during the Weimar Republic, the Third Reich and the immediate aftermath...
took both locomotives over as 79 001 and 79 002, but retired them by 1932.
The serial number 79 001 was allocated from 1938 to 1947 to BLE No. 44
BLE No. 44
Locomotive No. 44 of the Brunswick State Railway was a tank locomotive for mixed passenger and goods traffic. The locomotive, built in 1934 by Krupp, had a 2-8-2T wheel arrangement and a two-cylinder superheated engine. Leading and trailing wheels were housed in a Bissel bogie...
of the former Brunswick State Railway Company
Brunswick State Railway Company
The Brunswick State Railway Company or BLE was a railway company in the Duchy of Brunswick, a former German state centred around the city of Brunswick ....
and from 1951 it was given to the former French locomotive, 242 TA - 602, which ended up in German hands after World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
Design features
The boilerBoiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
barrel comprised 2 shells with a diameter of 1,450 mm. On the top were two steam domes which were connected by a pipe inside the boiler. Between steam dome and chimney was a sand box. The firebox was made of copper and position over the first axle of the rear drive. The smokebox
Smokebox
A smokebox is one of the major basic parts of a Steam locomotive exhaust system. Smoke and hot gases pass from the firebox through tubes where they pass heat to the surrounding water in the boiler. The smoke then enters the smokebox, and is exhausted to the atmosphere through the chimney .To assist...
superheater
Superheater
A superheater is a device used to convert saturated steam or wet steam into dry steam used for power generation or processes. There are three types of superheaters namely: radiant, convection, and separately fired...
was of the Schmidt type.
The locomotive frame
Locomotive frame
A locomotive frame is the structure that forms the backbone of the railway locomotive, giving it strength and supporting the superstructure elements such as a cab, boiler or bodywork. The vast majority of locomotives have had a frame structure of some kind...
comprised an inside frame of 28 mm thick plate, and an outside frame for the hollow axles of 20 mm thick plate.
The four-cylinder compound engines were arranged horizontally on the outside and each drove its centre axle
Sources
- Fritz Näbrich, Günter Meyer, Reiner Preuß: Lokomotiv-Archiv Sachsen 1. transpress VEB Verlag für Verkehrswesen, Berlin, 1984.
- Manfred Weisbrod, Hans Müller, Wolfgang Petznick: Deutsches Lok-Archiv: Dampflokomotiven 3 (Baureihen 61 - 98). transpress, Berlin, 1994, ISBN 3-344-70841-4
External links
- Photo
- There is a relevant English-language forum at Railways of Germany
