The engines of DR Class 99.23 are
metre gauge
Metre-gauge railways are narrow-gauge railways with track gauge of or 1 metre.
The metre gauge is used in around of tracks around the world. It was used by European colonial powers, such as the French, British and German Empires. In Europe, la ...
tank locomotive
A tank locomotive or tank engine is a steam locomotive that carries its water in one or more on-board water tanks, instead of a more traditional tender. Most tank engines also have bunkers (or fuel tanks) to hold fuel; in a tender-tank locom ...
s, that were procured by the
Deutsche Reichsbahn (DR) in
East Germany
East Germany, officially the German Democratic Republic (GDR; german: Deutsche Demokratische Republik, , DDR, ), was a country that existed from its creation on 7 October 1949 until its dissolution on 3 October 1990. In these years the state ...
from 1954 to 1956. When they entered service they had operating numbers 99 231–99 247. Today they are numbered 99 7231–99 7247.
History
A total of 17 locomotives were bought by the DR between 1954 and 1956 for the railways of the
Harzquerbahn
The Harz Railway or Trans-Harz Railway (german: Harzquerbahn) was formerly the main line of the Harz Narrow Gauge Railways (''Harzer Schmalspurbahnen'' or ''HSB'') and runs north to south right across the Harz Mountains from Wernigerode to Nordhaus ...
and
Brockenbahn, and for the line from
Eisfeld to
Schönbrunn to replace much of the outdated fleet. Four locomotives were built for the USSR in 1956, but their ultimate fate is unknown. The first seven units (99 231 to 99 237) were originally equipped with two
Krauss-Helmholtz bogies. Due to problems with curve running, the engines in the second series were given
Beugniot levers between the first and second
coupled axles in addition to the Krauss-Helmholtz bogies (according to other sources also a
Schwartzkopff-Eckhardt II bogie[EK-Themen 18, Brockenlok 99.22, Eisenbahn-Kurier, Freiburg 1995][Website of the ''Freundeskreises Selketalbahn'' (see below)]).
The locomotives of the first series were subsequently modified with Beugniot levers, some in the early 1960s, others in 1973/74 (on the Harz lines). The thinner wheel flanges of the driving wheels were completely removed later to achieve better curve running, resulting in the second series not having a rigid wheelbase.
The drive was applied to the third coupled axle, the locomotives had
Heusinger valve gear with unsprung ''Müller''
balanced slide valve
The slide valve is a rectilinear valve used to control the admission of steam into and emission of exhaust from the cylinder of a steam engine.
Use
In the 19th century, most steam locomotives used slide valves to control the flow of steam into ...
s and, later,
Trofimoff valve
The Trofimoff valve (german: Trofimoff-Schieber) (also ''Trofimov'', ''Troffimoff'' or ''Trofimof'') is a springless pressure-compensation piston valve for steam locomotives.
Overview
The function of the valve is to improve efficiency when runnin ...
s.
These ''
Neubaulokomotiven'' were a fully welded development of the standard locomotives (''
Einheitsloks'') of the
DRG Class 99.22. In contrast to those, the 99.23-24s had mixer-
preheaters and
plate frames. However, the latter caused maintenance difficulties from the outset due to cracks and distortion. 10 locomotives (99 7232, 7240, 7245, 7239, 7236, 7234, 7237, 7241, 7243, 7247) were equipped from 2004 onward with a redesigned plate frame and 5 of those (99 7232, 7240, 7245, 7239, 7236) with new, welded steam
cylinders
A cylinder (from ) has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base.
A cylinder may also be defined as an infini ...
. The 17 DR engines are all extant and based in the Harz; some however are no longer working.
The 17 German engines were converted to primary oil-firing between 1977 and 1983, and together with the DRG Class 99.22 are the most powerful German narrow gauge steam locomotives ever constructed. They were later converted back to coal-firing and are primarily used on the line up to the
Brocken
The Brocken, also sometimes referred to as the Blocksberg, is the highest peak in the Harz mountain range and also the highest peak in Northern Germany; it is near Schierke in the German state of Saxony-Anhalt between the rivers Weser and Elbe. ...
from
Wernigerode
Wernigerode () is a town in the district of Harz, Saxony-Anhalt, Germany. Until 2007, it was the capital of the district of Wernigerode. Its population was 35,041 in 2012.
Wernigerode is located southwest of Halberstadt, and is picturesquely s ...
.
Their operating numbers changed from 99 231 ''et seq'' to 99 7231 ''et seq'' on the introduction of computerised numbers in 1970 and then again to 99 0231 ''et seq'' on conversion to oil-firing. The computer numbers are still valid because the
HSB retains those allocated in the
1970 DR renumbering scheme.
The engines can carry of coal and of water.
Locomotives
* 99 7231: out of service since 2001
* 99 7232: working, new frame
* 99 7233: out of service since 1999
* 99 7234: working, new feame
* 99 7235: out of service since 2020
* 99 7236: working, new frame
* 99 7237: working, new frame
* 99 7238: working
* 99 7239: working, new frame
* 99 7240: working, new frame
* 99 7241: working, new frame
* 99 7242: out of service since 2010
* 99 7243: working, new frame
* 99 7244: working, undergoing conversion to oil-firing
* 99 7245: working, new frame
* LKM 134023: built for & lost in the USSR
* LKM 134024: built for & lost in the USSR
* LKM 134025: built for & lost in the USSR
* LKM 134026: built for & lost in the USSR
* 99 7246: out of service since 1996
* 99 7247: working, new frame
Photo gallery
Image:7232Wernigerode.jpg, 99 7232
Image:Harzer Schmalspurbahnen 9972340.jpg, 99 7234
Image:Deutsche Reichsbahn 99_7237.jpg, 99 7237
See also
*
*
Neubaulok
The German term ''Neubaulokomotive'' () specifically refers to those steam locomotives which were newly designed and built, either for the Deutsche Bundesbahn in West Germany or the Deutsche Reichsbahn in East Germany, after the Second World War.
...
References
* Obermayer, Horst J. ''Taschenbuch Deutsche Schmalspur-Dampflokomotiven'', Franckh'sche Verlagshandlung, Stuttgart, , 1971, pp. 60–61.
* Vetter, Klaus J. ''Das große Handbuch deutscher Lokomotiven'', Bruckmann, München, , 2001, pp 191–192.
*
* Weisbrod, Manfred; Wiegard, Hans; Müller, Hans; Petznick, Wolfgang. ''Deutsches Lok-Archiv: Dampflokomotiven 4 (Baureihe 99)'', Transpress, Berlin,, 1995, pp 53–57.
External links
''Freundeskreis Selketalbahn'' website
{{DEFAULTSORT:Dr Class 99.23-24
99.023
2-10-2T locomotives
99.23-24
Railway locomotives introduced in 1954
Metre gauge steam locomotives
1′E1′ h2t locomotives
LKM locomotives