The Württemberg Hz were 0-10-0

rack Rack or racks may refer to: Storage and installation * Amp rack, short for amplifier rack, a piece of furniture in which amplifiers are mounted * Bicycle rack, a frame for storing bicycles when not in use * Bustle rack, a type of storage bin ...

and adhesion

steam locomotives A steam locomotive is a locomotive that provides the force to move itself and other vehicles by means of the expansion of steam. It is fuelled by burning combustible material (usually coal, oil or, rarely, wood) to heat water in the locomot ...

, that were initially developed by the

Royal Württemberg State Railways The Royal Württemberg State Railways (''Königlich Württembergische Staats-Eisenbahnen'' or ''K.W.St.E.'') were the state railways of the Kingdom of Württemberg (from 1918 the ''People's State of Württemberg'') between 1843 and 1920. Please ...

(''Königlich Württembergische Staats-Eisenbahnen''), but were delivered to the

Deutsche Reichsbahn-Gesellschaft The ''Deutsche Reichsbahn'', also known as the German National Railway, the German State Railway, German Reich Railway, and the German Imperial Railway, was the German national railway system created after the end of World War I from the regiona ...

(DRG) in the mid-1920s.

Design

The locomotives had a ''Winterthur'' cogwheel drive with one lower and one upper pair of

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 in ...

. On the level, they ran like normal steam locomotives using the lower, higher pressure, pair of cylinders driving on the third

coupled axle On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons (or turbine, in the case of a steam turbine locomotive). On a conventional, non-articulated locomotive, the driving wheels are all coupled tog ...

. Before entering the rack section the upper drive was started using live steam. At the same time the r.p.m. was matched to the running speed so that entry into the rack section could be achieved smoothly. Once the cogwheel had engaged the rack, the exhaust from the lower cylinders was routed to the upper, lower pressure, ones using a change valve and was expelled from the chimney. The locomotive now worked as a

compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struc ...

. The cylinders of the adhesion and cogwheel drives have the same diameters (Ø 560 mm). The difference in volume (after expulsion from the adhesion system, the steam doubles its volume) is compensated for because the cogwheel drive turns twice as fast. The driving cogwheel is housed in a special frame, that lies above the second and third axle. The higher cogwheel drive and the lower cogwheel are coupled via an intermediate gear with a transmission ratio of 1:2.43. The

boiler A boiler is a closed vessel in which fluid (generally water) is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications, including water heating, central ...

s were given steel fireboxes and the frame was reinforced, especially in the area of the drive. The outermost axles, which had side play, were given return springs to minimise hunting.

Operations

The DRG organised these

tank locomotives 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 locomot ...

into Class 97.5 in their

numbering plan A telephone numbering plan is a type of numbering scheme used in telecommunication to assign telephone numbers to subscriber telephones or other telephony endpoints. Telephone numbers are the addresses of participants in a telephone network, reac ...

. They were employed on the 1-in-10 Honau–Lichtenstein rack railway, 2.2 km long, which employed a '' Riggenbach- Klose'' rack system., p 299. Apart from 97 503, which was destroyed during the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

, remained there until their retirement in 1961. Number 97 502 returned to its producer, the ''

Maschinenfabrik Esslingen Maschinenfabrik Esslingen (ME), was a German engineering firm that manufactured locomotives, tramways, railway wagons, roll-blocks, technical equipment for the railways, (turntables and traversers), bridges, steel structures, pumps and boiler ...

'' (now owned by ''

Daimler-Benz The Mercedes-Benz Group AG (previously named Daimler-Benz, DaimlerChrysler and Daimler) is a German multinational automotive corporation headquartered in Stuttgart, Baden-Württemberg, Germany. It is one of the world's leading car manufactu ...

'') at

Esslingen am Neckar Esslingen am Neckar (Swabian: ''Esslenga am Neckor'') is a town in the Stuttgart Region of Baden-Württemberg in southern Germany, seat of the District of Esslingen as well as the largest town in the district. Within Baden-Württemberg it is th ...

and was set up as a monument there, before being moved to

Bochum-Dahlhausen Railway Museum The Eisenbahnmuseum Bochum-Dahlhausen is a railway museum situated south of the city of Bochum in the state of North Rhine-Westphalia, Germany. It was founded by DGEG, the German Railway History Company in 1977 and is based in a locomotive de ...

. From 1952 locomotives 97 502 and 504 were modernised in the ''Maschinenfabrik Esslingen'' in order to raise their running speed in both adhesion and cogwheel working. To increase their radius of action numbers 97 501, 502 and 504, the coal tank capacity was increased by 1 tonne.

Preserved

Of the four machines built, three have been preserved: :97501 in

Reutlingen Reutlingen (; Swabian: ''Reitlenga'') is a city in Baden-Württemberg, Germany. It is the capital of the eponymous district of Reutlingen. As of June 2018, it has a population of 115,818. Reutlingen has a university of applied sciences, which ...

(information a
www.zhl.de
:97502 at the

Bochum Bochum ( , also , ; wep, Baukem) is a city in North Rhine-Westphalia. With a population of 364,920 (2016), is the sixth largest city (after Cologne, Düsseldorf, Dortmund, Essen and Duisburg) of the most populous German federal state of N ...

-Dahlhausen :97504 at the ''

Deutsches Technikmuseum Berlin (German Museum of Technology) in Berlin, Germany is a museum of science and technology, and exhibits a large collection of historical technical artifacts. The museum's main emphasis originally was on rail transport, but today it also features e ...

References

* {{DEFAULTSORT:Wurttemberg Hz Railway locomotives introduced in 1923 0-10-0 locomotives Deutsche Reichsbahn-Gesellschaft locomotives Hz Esslingen locomotives Standard gauge locomotives of Germany Rack and cog driven locomotives E h2t locomotives E h4vt locomotives Freight locomotives

Design

Operations

Preserved

See also

References