{{Short description|Class of narrow gauge diesel-hydraulic locomotives}} {{use dmy dates|date=March 2025}} {{Infobox locomotive | name = DB Class V 51 and V 52<br>(after 1968 Class 251 and 252) | powertype = Diesel-hydraulic | image = 251 902-3 Warthausen 17.6.1988.jpg | alt = Red two-bogie diesel locomotive with a single off-centre cab and lower bonnets at each end. The nearest bonnet is lower than the other one. | imagesize = 250px | caption = 251 902 with a steam engine at Warthausen station, 1988 | designer = | builder = Gmeinder (under license) | serialnumber = {{ubl |V 51 901 to 903 |V 52 901 to 902}} | buildmodel = | builddate = | totalproduction = {{ubl |V 51 : 3 |V 52 : 2}} | rebuilder = | rebuilddate = | numberrebuilt = | whytetype = | aarwheels = | uicclass = B′B′ | gauge = {{ubl|V 51 : {{RailGauge|750mm}} |V 52 : {{RailGauge|1000mm}}}} | trucks = | bogies = | wheeldiameter = {{convert|850|mm|in|abbr=on}} (new) | wheelbase = {{convert|1,700|mm|in|abbr=on}}(bogies)<br>{{convert|4.080|m|ftin|abbr=on}} (between pivot pins) | length = {{ubl |V 51 : {{convert|9.81|m|ftin|abbr=on}} |V 52 : {{convert|9.78|m|ftin|abbr=on}}}} (over couplings) | width = {{convert|2.400|m|ftin|abbr=on}} | height = {{convert|3.484|m|ftin|abbr=on}} | frametype = | axleload = | locoweight = {{convert|39.0|t|abbr=on}} | fueltype = | fuelcap = {{convert|1800|L|abbr=on}} | coolantcap = | watercap = | consumption = | electricsystem = | collectionmethod = | primemover = 2 x MWM TRHS 518A | enginetype = | aspiration = | displacement = | alternator = | generator = | tractionmotors = | cylindercount = | cylindersize = | transmission = Hydraulic (TwinDisc) | maxspeed = {{convert|40|km/h|abbr=on}} | poweroutput = 2x {{convert|198|kW|hp|abbr=on}} | tractiveeffort = starting {{convert|134|kN|abbr=on}}<ref name="meb 1965-12">{{cite magazine |title=Dieselhydraulische Schmalspurlokomotive V 51/52 der DB |language=de |trans-title=Diesel-hydraulic Narrow-gauge Locomotive V 51/52 of DB |magazine=Modelleisenbahner |date=December 1965 |last=Schindler |first=Rolf |pages=373–374 |publisher=Transpress |url=https://archive.org/details/ModellEisenbahner/ModellEisenbahner1965-12 |access-date=27 March 2025}}</ref> | locobrakes = | trainbrakes = | safety = | multipleworking = | operator = | operatorclass = | numinclass = | fleetnumbers = | officialname = | nicknames = | locale = | deliverydate = | firstrundate = | lastrundate = | retiredate = {{ubl|from DB: |V 51 901 : 23.02.1971 |V 51 902 : 31.03.1983 |V 51 903 : 31.03.1983 |V 52 001 : ~1973/4 |V 52 002 : ~1973/4}} | restoredate = | scrapdate = | currentowner = | disposition = | minimumcurve ={{convert|70|m|0|abbr=on}} |notes = Sources :<ref name="gm">[http://www.loks-aus-kiel.de/index.php?nav=1401518&lang=1 MaK - Ein weiteres Typenprogramm (400 C / 400 BB / 500 C)] Technical data for Gmeinder license built V 51 and V 52 ''loks-aus-kiel.de''</ref> except were noted }}
The '''DB V{{nbsp}}51''' and '''DB V{{nbsp}}52''' (from 1968: '''DB Class 251''' and '''Class 252''') are two classes of narrow-gauge diesel-hydraulic locomotives built in 1964 for the Deutsche Bundesbahn. The Class V{{nbsp}}51 were built for {{RailGauge|750mm}} and the Class V{{nbsp}}52 for {{RailGauge|1000mm}} gauge lines respectively. The locomotives were built to replace steam locomotives on the narrow gauge lines in Baden-Württemberg and apart from the gauge are identical. Due to line closures the locomotives did not work for long for the Deutsche Bundesbahn, and subsequently worked for different private companies in Italy, Spain and Austria.
==Background==
In the early 1960s the narrow-gauge railways of Baden-Württemberg were still operated by 13 steam locomotives. To enable their withdrawal, and to continue operations on the {{RailGauge|750mm|disp=1}} and {{RailGauge|1000mm|disp=1}} gauge railways, the state of Baden-Württemberg subsidised the production of diesel locomotives by the Deutsche Bundesbahn.<ref name="ER 2024-03 A">{{cite magazine |title=Wiederaufstandene Öchsle-Lok |language=de |trans-title=Resurrected Öchsle loco |pages=63–68 |last=Bloem |first=Hendrik |magazine=Eisenbahn Romantik |date=March 2024 |isbn=978-3-98702-135-0 |issn=2702-1246 |publisher=GeraMond}}</ref>
===Development and design=== Thus the Deutsche Bundesbahn was asked to provide locomotives with suitably low axle load, suitable for both freight and passenger work, and which were suitable for use on small radius curves. High speed was not a primary requirement, more so ease of maintenance and a reliable design.
A design for a four-axle, twin-bogie locomotive was developed based on the MaK 400 BB built in 1959 for the {{langx|de|Alsen´sche Portland-Cementfabrik KG|label=none}}. Apart from the rail gauge and couplings both classes shared the same design. All had two MWM diesel engines each with an output of {{convert|270|hp|kW|abbr=on}} @ 1600 rpm. located in the longer end. The shorter end contained the auxiliary diesel engine, the batteries, the compressor and the diesel tanks.<ref name="meb 1965-12"/>
The transmission was via a ''TwinDisc 11500 MS450'' torque converter with a MaK 3.162.04 final drive. The locomotive's maximum service speed was {{convert|40|km/h|abbr=on}}<ref name="meb 1965-12"/> though the actual top speed was around {{convert|65|km/h|abbr=on}}.{{citation needed|date=March 2025}} The ''Sifa'' safety system was fitted but not ''Indusi'' because of the slow speeds the trains used on the branch lines.
===Construction=== The locomotives were constructed by Gmeinder under license and delivered in 1964.<ref name="meb 1965-12"/> Within each class the locomotives were numbered from 900 upwards - like narrow gauge steam locomotives had serial numbers 900 upwards.
===Renumbering=== In 1968 the locomotives class numbers were changed, the V{{nbsp}}51 locomotives became Class 251 and the V{{nbsp}}52 machines became Class 252. The serial numbers within each class remained unchanged.
{|class="wikitable" !colspan=2|Class !colspan=2|Loco number !rowspan=2|Gmeinder Builder number !rowspan=2|Notes |- !Pre 1968 !Post 1968 !Pre 1968 !Post 1968 |- |rowspan=3|V 51 |rowspan=3|251 |V 51 901 |251 901 |5327 | |- |V 51 902 |251 902 |5328 | |- |V 51 903 |251 903 |5329 | |- |rowspan=2|V 52 |rowspan=2|252 |V 52 901 |252 901 |5325 | |- |V 52 902 |252 902 |5326 | |- |}
==Work history==
===Class V 51=== thumb|alt=See caption|251 901 in May 2024 at Putbus The three V{{nbsp}}51 locomotives were delivered in 1964 to their respective lines: V 51 901 to the {{ill|Federseebahn|de}},<ref name="ER 2024-03 A"/> V 51 902 to the Biberach-Warthausen-Ochsenhausen line (also known as the {{ill|Öchsle (railway)|de|Öchsle (Bahn)|lt=Öchsle}}) and V 51 903 to the {{ill|Bottwartalbahn|de}},<ref name="schwäbische 2020-09-27"/> where they replaced the old steam engines. All three locomotives performed well in their duties, however such trouble-free operation could not stop the decline of the Baden-Württemberg narrow gauge lines
After the closure of the Federseebahn in 1968, 251 901 moved to join 251 902 on the Bottwartalbahn.<ref name="LGB"/> When the Bottwartalbahn also closed the two displaced locomotives were transferred to the Biberach-Ochsenhausen line in 1970 to replace steam locomotives.<ref name="ER 2024-03 A"/> At this time the line still had substantial freight operations using rollbocks for the Liebherr refrigerator factory in Ochsenhausen,<ref name="ER 2024-03 B">{{cite magazine |title=Liebe auf den zweiten Blick: Das Öchsle und "meine" 251 902 |language=de |trans-title=Love at second sight: The Öchsle and "my" 252 902 |pages=70–71 |last=Schumacher |first=Wolfgang |magazine=Eisenbahn Romantik |date=March 2024 |isbn=978-3-98702-135-0 |issn=2702-1246 |publisher=GeraMond}}</ref> assuring that this section of the line remained open for almost 20 years after the end of passenger traffic and the closure of the section to Warthausen.<ref name="LGB"/>
There was no need for all three locomotives on this shorter route so 251 901 was sold in 1971 to the {{ill|Steiermärkische Landesbahnen|de}} (StLB) in Austria and regauged to {{RailGauge|760mm|lk=on}}. There the locomotive was renumbered to VL{{nbsp}}21 and operated on the Thörlerbahn until 1998 when it was purchased by the Rügensche Kleinbahn.<ref name="LGB">{{cite magazine |title=Ready for the Island |last=Bradler |first=Thomas |pages=6–8 |magazine=LGB Club News |year=2012 |number=3 |publisher=Märklin |url=https://www.maerklin.de/fileadmin/media/clubs/en/lgb/LGB-News-03-2012-en.pdf |access-date=28 March 2025}}</ref> It has been regauged back to {{RailGauge|750mm|disp=1}} and {{As of|2024|lc=y}} is in operation.<ref name="ER 2024-03 A"/><ref>[http://www.loks-aus-kiel.de/index.php?nav=1401521&lang=1&id=13638&action=portrait Fahrzeugportrait Gmeinder 5327] Gmeinder 5327 details ''loks-aus-kiel.de''</ref>
251 902 and 251 903 continued working on the Biberach to Ochsenhausen line, pulling freight trains, until its closure on 31 March 1983. After the closure 251 902 was bought from DB for use on the Warthausen-Ochsenhausen line under its new guise as a heritage railway<ref name="ER 2024-03 B"/> It remained there until 1996 when the locomotive was withdrawn.<ref>[http://www.loks-aus-kiel.de/index.php?nav=1401521&lang=1&id=13641&action=portrait Fahrzeugportrait Gmeinder 5328] Gmeinder 5328 details ''loks-aus-kiel.de''</ref>
251 903 was sold in 1984 to the Italian firm ''Gleismac Italiana SpA'' in Gazzo di Bigarello and then in 1985 to the Spanish track company COMSA where it had exchange bogies for use on {{RailGauge|1000mm}}, {{RailGauge|1435mm}} and {{RailGauge|1668mm}} gauges.<ref>[http://www.loks-aus-kiel.de/index.php?nav=1401521&lang=1&id=19160&action=portrait Fahrzeugportrait Gmeinder 5329] Gmeinder 5329 details ''loks-aus-kiel.de''</ref> In 2009 the locomotive returned to the Öchsle railway<ref>{{cite web |url=https://www.schwaebische.de/regional/biberach/ochsenhausen/einstige-oechsle-stammlok-ist-endgueltig-zurueck-1085459 |title=Einstige Öchsle-Stammlok ist endgültig zurück |language=de |trans-title=One time Öchsle locomotive is finally back |work=Schwäbische Zeitung |date=11 September 2009 |access-date=28 March 2025}}</ref> and {{as of|2020|lc=y}} was under restoration and had been rebuilt back to {{RailGauge|750mm|disp=1}} gauge.<ref name="schwäbische 2020-09-27">{{cite web |url=https://www.schwaebische.de/regional/biberach/ochsenhausen/oechsle-diesellok-kehrt-auf-heimat-gleise-zurueck-154133 |title=Meilenstein erreicht: Öchsle Lok V 51 903 kehrt auf die Heimat-Gleise zurück |language=de |trans-title=Milestone reached: Öchsle loco V 51 903 returns to its home rails |work=Schwäbische Zeitung |date=27 September 2020 |access-date=28 March 2025 |url-access=registration}}</ref>
===Class V 52===
thumb|alt=V 52 locomotive with a taller and wider cab|Albtalbahn 62 in 1982 The two V{{nbsp}}52 locomotives were delivered in 1964 to the {{ill|Mosbach-Mudau railway line|de|Bahnstrecke Mosbach–Mudau}} to replace the 4 steam locomotives that were working there. The locomotives worked passenger services with four new passenger cars procured 1965 and goods traffic using rollbocks to transport standard-gauge freight wagons.
Despite the dieselisation the line closed in 1973. Both locomotives were rebuilt to standard gauge and sold to local private rail companies to recover the state grant which had been used in their purchase. Locomotive 252 901 became 62 on the Albtalbahn in Karlsruhe.<ref>{{cite magazine |title=Germany (West) (BRD) - Karlsruhe |magazine=Modern Tramway and Rapid Transit Review |date=December 1974 |volume=37 |number=444 |page=430 |url=https://archive.org/details/moderntramwayrap37unse_10 |access-date=27 March 2025 |url-access=registration}}</ref><ref name="g521">[http://www.loks-aus-kiel.de/index.php?nav=1401521&lang=1&id=19161&action=portrait Fahrzeugportrait Gmeinder 5325] Gmeinder 5325 details ''loks-aus-kiel.de''</ref> As part of the rebuilding at Gmeinder the cab was broadened. The second locomotive, 252 902, was sold in 1974 to the Südwestdeutsche Eisenbahn-Gesellschaft mbH (SWEG), numbered VL 46-01<ref name="g522">[http://www.loks-aus-kiel.de/index.php?nav=1401521&lang=1&id=19162&action=portrait Fahrzeugportrait Gmeinder 5326] Gmeinder 5326 details ''loks-aus-kiel.de''</ref> and used on the Kaiserstuhlbahn.
In 1985, both locomotives (along with 251 903 were sold to the Italian company ''Gleismac Italiana SpA'' in Gazzo di Bigarello. From there, in 1987, 252 901 went without any structural changes to the construction company ''Francesco Ventura SrL'' in Paola (southern Italy) where it was numbered as 7152 T.<ref name="g521"/> 252 902 was converted back to meter gauge and sold to the Genova–Casella railway (FGC) in 1986. Later in the 1990s work was undertaken on it to enable a snow plow to be fitted. The locomotive has been restored between 2008 and 2015 by the Italian company Tesmec based in Monopoli (BA) and {{as of|2021|lc=y}} is in working condition.<ref name="g522"/>
==References== {{reflist}}
===Sources=== *DB V 51 **[http://www.schmalspureisenbahnen.de/lok.php?ID=oh&Loknr=5 Das Öchsle :Biberach - Ochsenhausen - Die Baureihe V 51] The Biberach-Ochsenhausen narrow gauge railway : The Class V 51 - history and design information ''schmalspureisenbahnen.de'' **[http://www.privat-bahn.de/V51.html Gmeinder V51/251] brief history and technical data ''privat-bahn.de'' *DB V 52 **[http://www.schmalspureisenbahnen.de/lok.php?ID=mm&Loknr=9 Mosbach - Mudau : Die Baureihe V 52] Mosbach to Mudau railway : The Class V 52 - history and design information ''schmalspureisenbahnen.de'' **[http://www.privat-bahn.de/V52.html Gmeinder V52/252] brief history and technical data ''privat-bahn.de''
==External links== {{commons category inline|DB Class V 51}}
{{commons category inline|DB Class V 52}}
{{German diesel locomotives}}
{{DEFAULTSORT:DB Class V 051}} Category:750 mm gauge locomotives Category:Metre-gauge diesel locomotives V 051 Category:B-B locomotives Category:Railway locomotives introduced in 1964 Category:Diesel–hydraulic locomotives of Germany