Midland Railway 1121 Class

{{Use dmy dates|date=April 2022}}

{{Infobox locomotive

| name = Midland Railway 1121 class

| image = LMS 1874.jpg

| alt =

| caption = LMS 1874

| powertype = Steam

| designer = Samuel W. Johnson

| builder = {{ubl|Derby Works (10)|Sharp, Stewart & Co. (5)|Robert Stephenson & Co. (40)}}

| ordernumber =

| serialnumber =

| buildmodel =

| builddate = 1895–1899

| totalproduction = 55

| rebuilder =

| rebuilddate =

| numberrebuilt =

| whytetype = 0-6-0T

| uicclass = C n2t

| driver =

| gauge = {{track gauge|ussg}}

| driverdiameter = {{convert|4|ft|6|in|m|3|abbr=on}}

| minimumcurve =

| wheelbase =

| engine total =

| wheelspacing = {{ubl|{{convert|7|ft|4|in|m|3|abbr=on}} +|{{convert|8|ft|2|in|m|3|abbr=on}}}}

| length =

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| coupled all =

| coupled 1 =

| coupled 2 =

| coupled 3 =

| weightondrivers =

| locoweight =

| fueltype =

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| watercap =

| tendercap =

| sandcap =

| fireboxtype =

| firearea =

| boiler = MR type A1

| boilertype =

| pitch =

| diameterinside =

| lengthinside =

| smalltubediameter=

| largetubediameter=

| boilerpressure = {{convert|160|lbf/in2|MPa|abbr=on}}{{sfn|Baxter|1982|p=118}}

| safetyvalvetype =

| feedwaterheater =

| totalsurface = {{convert|1120|sqft|m2|abbr=on}}{{sfn|Baxter|1982|p=118}}

| tubearea =

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| fluearea =

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| superheatertype =

| superheaterarea =

| cylindercount = Two, inside

| cylindersize = {{convert|17|x|24|in|mm|0|abbr=on}}

| valvegear =

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| valvelead =

| transmission =

| trainheating =

| locobrakes =

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| operator = {{ubl|Midland Railway|London, Midland and Scottish Railway|British Railways}}

| operatorclass =

| powerclass = 1F

| numinclass =

| fleetnumbers = {{ubl|MR: 1121–1130, 2248–2252, 2361–2390, 2571–2580|LMS: 1845–1899|BR: 41846–41890 (with gaps)}}

| officialname =

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| axleloadclass =

| locale = London Midland Region

| deliverydate =

| firstrundate =

| lastrundate =

| withdrawndate = December 1930 – July 1963

| preservedunits =

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| currentowner =

| disposition = All scrapped

| notes =

}}

The Midland Railway 1121 class was a class of 0-6-0T tank locomotives designed by Samuel W. Johnson for the Midland Railway. Fifty-five were built between 1895 and 1900: ten by the railway company's Derby Works, five by Sharp, Stewart and Company, and the remaining forty by Robert Stephenson and Company.