GWR 3150 Class

{{Short description|Class of 41 two-cylinder 2-6-2T locomotives}}

{{Use dmy dates|date=January 2018}}

{{Use British English|date=January 2018}}

{{Infobox locomotive

| powertype = Steam

| name = GWR 3150 Class {{cite book |title= GWR Engines - Names, Numbers, Types, Classes, ETC. of Great Western Railway Locomotives. |publisher= Great Western Railway |year= 1938 | page = 70}}

| image = Gloucester GW Locomotive Depot geograph-2547177-by-Ben-Brooksbank.jpg

| caption = 3171 at Gloucester (Horton Road) Depot 1948

| designer = George Jackson Churchward

| builder = GWR Swindon Works

| builddate = 1906–1908

| ordernumber = Lots 159, 169, 172

| serialnumber = 2157, 2239–2258, 2280–2299

| totalproduction = 41

| whytetype = 2-6-2T

| gauge = {{Track gauge|56.5in|allk=on}}

| leadingdiameter = {{convert|3|ft|2|in|m|3|abbr=on}}

| driverdiameter = {{convert|5|ft|8|in|m|3|abbr=on}}

| trailingdiameter = {{convert|3|ft|8|in|m|3|abbr=on}}

| length = {{convert|41|ft|0|in|m|2|abbr=on}} over buffers

| locoweight = {{long ton|64|13}}
({{convert|64|LT|13|Lcwt|t ST|1|abbr=on|disp=output only}}) empty
{{long ton|81|12}}
({{convert|81|LT|12|Lcwt|t ST|1|abbr=on|disp=output only}}) full

| fueltype = Coal

| fuelcap =

| watercap = {{convert|2000|impgal|abbr=on}}

| boilerpressure = {{convert|200|lbf/in2|MPa|2|abbr=on}}

| firearea = {{convert|20.56|sqft|m2|abbr=on}}

| boiler = GWR Standard No. 4

| tubearea = {{convert|1349.64|sqft|m2|abbr=on}}

| fluearea =

| tubesandflues =

| fireboxarea = {{convert|128.72|sqft|m2|abbr=on}}

| cylindercount = Two, outside

| cylindersize = {{convert|18+1/2|x|30|in|mm|0|abbr=on}}

| valvegear = Stephenson

| valvetype = Piston valves

| tractiveeffort = {{convert|25670|lbf|kN|abbr=on}}

| factorofadhesion =

| trainheating =

| locobrakes =

| locobrakeforce =

| numinclass = 41

| fleetnumbers = 3150-3190

| trainbrakes = Vacuum

| powerclass = 4MT

| firstrundate = 1907

}}

The Great Western Railway (GWR) 3150 Class was a class of 2-6-2T side tank steam locomotive.