View source for JNR Class D50

{{short description|Class of 380 Japanese 2-8-2 locomotives}}
{{Infobox locomotive
| name = Japanese National Ry Class D50<br/>China Railways 解放<sub>16</sub> class
| image = JGR-D50SteamLocomotive.jpg
| alt = 
| caption = D50 319 in 1935
| powertype = Steam
| designer = Tokichi Ogasawara and Hideo Shima
| builder = {{ubl|[[Kawasaki Heavy Industries Rolling Stock Company|Kawasaki]] (204)|[[Hitachi]] (80)|[[Kisha Seizo|Kisha Seizō]] (69)|[[Nippon Sharyo|Nippon Sharyō]] (27)}}
| ordernumber = 
| serialnumber = 
| buildmodel = 
| builddate = 1923–1931
| totalproduction = 380
| rebuilder = 
| rebuilddate = 
| numberrebuilt = 
| whytetype = [[2-8-2]]
| uicclass = 1′D1′ h2
| driver = <!-- e.g. 1st, 2nd  or 3rd coupled axle -->
| gauge = {{track gauge|1067mm|lk=on}}
| leadingdiameter = 
| driverdiameter = {{convert|1400|mm|in|2|abbr=on}}
| trailingdiameter = 
| tenderdiameter = <!-- tender wheel diameter -->
| minimumcurve = 
| wheelbase = 
| engine total = 
| leading = 
| drivers = <!-- USA terminology -->
| coupled = <!-- British terminology -->
| trailing = 
| tender total = 
| tendertruck = <!-- USA terminology -->
| tenderbogie = <!-- British terminology -->
| pivotcentres = <!-- Garratts, diesels and electrics -->
| wheelspacing = <!-- coupled wheels with asymmetrical wheel spacing -->
| length = {{convert|17248|mm|ftin|frac=4|abbr=on}}
| over couplers = 
| over bufferbeams = 
| width = 
| height = {{convert|3955|mm|ftin|frac=8|abbr=on}}
| frametype = 
| axleload = {{convert|14.70|t}}
| leadingbogie/pony = <!-- load on leading bogie or pony wheel -->
| coupled all = <!-- when the load on all coupled wheels are the same -->
| coupled 1 = <!-- load on 1st coupled wheel -->
| coupled 2 = <!-- load on 2nd coupled wheel -->
| coupled 3 = <!-- etc. -->
| coupled 4 = 
| coupled 5 = 
| coupled 6 = 
| coupled 7 = 
| coupled 8 = 
| trail bogie/pony = <!-- load on trailing bogie or pony wheel -->
| tenderbogieload = <!-- load per tender bogie, use "Truck 1:<br>Bogie 2:" if different -->
| tenderaxle = <!-- use "Axle 1:", etc with "<br>" for line breaks -->
| weightondrivers = 
| locoweight = {{convert|78.14|t}}
| tenderweight = {{convert|49|t}}
| locotenderweight = 
| tendertype = 
| fueltype = 
| fuelcap = 
| watercap = 
| tendercap = 
| sandcap = 
| fireboxtype = <!-- Round-top, Belpaire, combustion chamber, etc. -->
| firearea = {{convert|3.25|m2|sqft|abbr=on}}
| boiler = <!-- Watson Standard no. x, etc -->
| boilertype = <!-- Domeless, etc -->
| pitch = <!-- height of boiler centreline above the railhead -->
| diameterinside = 
| lengthinside = {{convert|5500|mm|ftin|frac=4}}
| smalltubediameter = {{convert|57|mm|in|frac=8|abbr=on}}, 90 off
| largetubediameter = {{convert|140|mm|in|frac=8|abbr=on}}, 28 off
| boilerpressure = {{convert|13.0|kg/cm2|MPa psi|sigfig=3|abbr=on}}
| safetyvalvetype = <!-- Salter spring balance, Ramsbottom, Pop, etc. -->
| feedwaterheater = 
| totalsurface = 
| tubearea = 
| archarea = 
| fluearea = 
| tubesandflues = {{convert|142.7|m2|abbr=on}}
| fireboxarea = {{convert|13.5|m2|abbr=on}}
| superheatertype = 
| superheaterarea = {{convert|64.4|m2|abbr=on}}
| cylindercount = Two, outside
| cylindersize = {{convert|570|x|660|mm|in|frac=16|abbr=on|disp=br()}}
| valvegear = 
| valvetype = 
| valvetravel = 
| valvelap = 
| valvelead = 
| transmission = 
| trainheating = 
| locobrakes = 
| locobrakeforce = 
| trainbrakes = 
| safety = 
| coupling = 
| maxspeed = {{convert|70|km/h|mph|0|abbr=on}}
| poweroutput = 
| tractiveeffort = {{convert|165.977|kN|lbf|0|abbr=on}}
| factorofadhesion = 
| operator = {{ubl|[[Japanese Government Railways]]|[[Japanese National Railways]]|[[Jichang Jidun Railway]]|[[Manchukuo National Railway]]|[[Central China Railway]]|[[China Railway]]}}
| operatorclass = JGR: 9900 → D50<br/>JNR: D50<br/>CCR: D50<br/>CR: ㄇㄎ<sub>16</sub> → 解放<sub>16</sub>
| powerclass = 
| numinclass = 
| fleetnumbers = D50 1-D50 380 (formerly 9900-9999,19900-19999,29900-29975)
| officialname = 
| nicknames = 
| axleloadclass = 
| locale = 
| deliverydate = 
| firstrundate = 
| lastrundate = 
| retiredate = 1965
| withdrawndate = 
| preservedunits = D50&nbsp;25, D50&nbsp;140
| restoredate = 
| scrapdate = 
| currentowner = 
| disposition = Two preserved (both in Japan), remainder scrapped
| notes = 
}}
The '''Class D50''' is a type of [[2-8-2]] [[steam locomotive]] built by the [[Japanese Government Railways]] (JGR), the [[Japanese National Railways]] (JNR) and various manufacturers from 1923 to 1931. The class name indicates that the locomotive has four sets of driving wheels (D) and belongs to one of the classes of [[tender locomotive]] allocated a number in the series 50 to 99 in the [[Japan Railways locomotive numbering and classification]] scheme of 1928. [[Hideo Shima]] designed the rest of the class until 1931. 

The design of the D50 was based on the [[JNR Class 9600]] which was introduced in 1916. A total of 380 Class D50 locomotives were built. Between 1951 and 1956 78 were rebuilt to [[JNR Class D60]] [[2-8-4]] Berkshire’s by the JNR. This class would later form the [[JNR Class D51]].

== Service in China ==

===Manchukuo National Railway===
{{main|China Railways JF5}}
In 1923, sixteen D50 class locomotives were exported to the [[Jichang Jidun Railway]] in [[Manchuria]], which designated them class 500 and numbered 501 through 516. Ten were built by Kawasaki (works nos. 970−971, 1140−1170) and six by Kisha Seizō (w/n 965−970), and though very similar to the Japanese D50 class, there were some slight differences in dimensions due to the larger [[loading gauge]] on Chinese lines. After the establishment of [[Manchukuo]], the Jichang Jidun Railway was nationalised along with other private railways to form the [[Manchukuo National Railway]]. The MNR classified these Mikana (ミカナ) class, numbered 6540−6555, renumbered 501−516 in 1938.<ref>小熊米雄 「満州のD50―吉長、吉敦鉄路の500形について」 交友社『鉄道ファン』 No.22 April 1963, pp.45-47</ref> After the establishment of the [[People's Republic of China]], China Railways designated them ㄇㄎ<sub>5</sub> (MK<sub>5</sub>) class in 1951,<ref name="crtable">中国铁道部1951年2月版《机车概要表》</ref> and subsequently 解放<sub>5</sub> (JF<sub>5</sub>) class in 1959.

===Central China Railway===
In 1939, D50 193 was converted to standard gauge and shipped to the [[Central China Railway]], where it operated primarily between [[Nanjing]] and [[Shanghai]]. This engine lasted in service on China Railways until 1955.<ref name="cr100">中国蒸汽機車世紀集影 (Centennial Collection of Chinese Steam Locomotives), China Railway Publishing House, July 2001, {{ISBN|7-113-04148-5}} (in Chinese)</ref>

===China Railways===
After the establishment of the [[People's Republic of China]], all the railways of China were taken over by the [[China Railway]], which classified the D50s as ㄇㄎ<sub>16</sub> (MK<sub>16</sub>) class in 1951,<ref name="crtable"/> later becoming class 解放<sub>16</sub>(JF<sub>16</sub>).

==Preserved examples==
Two D50s are preserved in Japan.<ref name="sasada2012">{{cite book |title = 国鉄&JR保存車大全 |trans-title=JNR & JR Preserved Rolling Stock Complete Guide| last = Sasada| first = Masahiro| publisher = Ikaros Publications Ltd.| date = September 2012 | location = Tokyo, Japan| page = 133| isbn = 978-4863206175}}</ref>
* '''D50 25:''' In a park in [[Kitami, Hokkaido]]
* '''D50 140:''' At the [[Kyoto Railway Museum]]

<gallery widths="150" heights="150" class="center">
File:JNR D50 25.JPG|D50 25 in Kitami, Hokkaido
File:JNR SL D50140.jpg|D50 140 at Umekoji Steam Locomotive Museum
</gallery>

==See also==
* [[Japan Railways locomotive numbering and classification]]
*[[JNR Class 9600]]
*[[JNR Class D51]]
*[[JNR Class D52]]
*[[JNR Class D60]]
*[[JNR Class D61]]
*[[JNR Class D62]]

==References==
{{commons category|D50 steam locomotives}}
{{Reflist}}

{{Jgrsteam}}
{{Japanloco}}
{{CCRloco}}
{{Locomotives of China}}

[[Category:1067 mm gauge locomotives of Japan]]
[[Category:Steam locomotives of Japan]]
[[Category:Steam locomotives of China]]
[[Category:2-8-2 locomotives]]
[[Category:Hitachi locomotives]]
[[Category:Kawasaki locomotives]]
[[Category:Kisha Seizo locomotives]]
[[Category:Nippon Sharyo locomotives]]
[[Category:Preserved steam locomotives of Japan]]
[[Category:Railway locomotives introduced in 1923]]
[[Category:1′D1′ h2 locomotives]]
[[Category:Freight locomotives]]