View source for GWR 3100 Class

{{Use dmy dates|date=January 2018}}
{{Use British English|date=January 2018}}
{{refimprove|date=March 2014}}
{{about|the 5 locomotives rebuilt in 1938/9 from the 3150 Class|the 40 locomotives built in 1903–06 as the 3100 class|GWR 5100 Class}}
{{Infobox Locomotive
| powertype = Steam
| name = GWR 3100 Class
| image = 
| caption = 
| designer = Churchward <br> (rebuilt by Collett)
| builder = GWR [[Swindon Works]]
| ordernumber = Lot 319
| builddate = 1906
| rebuilddate = 1938
| numberrebuilt = 5
| whytetype = [[2-6-2T]]
| uicclass = 1'C1 h2t <!-- Radial rear truck -->
| gauge = {{track gauge|uksg|allk=on}}
| leadingdiameter = {{convert|3|ft|0|in|m|3|abbr=on}}
| driverdiameter = {{convert|5|ft|3|in|m|3|abbr=on}}
| trailingdiameter = {{convert|3|ft|8|in|m|3|abbr=on}}
| minimumcurve = {{convert|6|chain|0}} normal,<br>{{convert|5|chain|0}} slow
| length = {{convert|41|ft|0|in|m|2|abbr=on}} over [[Buffer (rail transport)|buffers]]
| width = {{convert|8|ft|11+1/4|in|m|3|abbr=on}}
| height = {{convert|13|ft|2|in|m|3|abbr=on}}
| axleload = {{long ton|19|3}}<br>({{convert|19|LT|3|Lcwt|ST|1|abbr=on|disp=output only}}) full
| weightondrivers = {{long ton|57|6}}<br>({{convert|57|LT|6|Lcwt|ST|1|abbr=on|disp=output only}}) full
| locoweight = {{long ton|81|9}}<br>({{convert|81|LT|9|Lcwt|ST|1|abbr=on|disp=output only}}) full
| fueltype = [[Coal]]
| fuelcap = 
| watercap = {{convert|2000|impgal|abbr=on}}
| boiler = GWR Standard No. 4
| boilerpressure = {{convert|225|lbf/in2|MPa|abbr=on}}
| firearea = {{convert|20.56|sqft|m2|abbr=on}}
| tubearea = {{convert|1349|sqft|m2|abbr=on}}
| fireboxarea = {{convert|128.72|sqft|m2|abbr=on}}
| superheatertype = 4-element or 6-element
| superheaterarea = 4-element: {{convert|136.64|sqft|m2|abbr=on}},<br>6-element: {{convert|181.10|sqft|m2|abbr=on}}
| cylindercount = Two, outside
| cylindersize = {{convert|18.5|x|30|in|mm|0|abbr=on}}
| tractiveeffort = {{convert|31170|lbf|kN|abbr=on}}
| operator = [[Great Western Railway|GWR]] » [[British Railways|BR]]
| operatorclass = 3100
| fleetnumbers = 3100–3104
| powerclass = GWR: D,<br>BR: 4MT
| axleloadclass = GWR: Red
| withdrawndate = 1957–1960
| disposition = All [[scrap]]ped
}}

The [[Great Western Railway]] (GWR) '''3100 Class''' was a class of [[2-6-2]]T [[side tank]] [[steam locomotive]].

== History ==
This class of large prairie was created in 1938 when [[Charles Collett|Collett]] rebuilt some of Churchward's [[GWR 3150 Class|3150 Class]] engines for use as [[Bank engine|bankers]], particularly from [[Severn Tunnel]] Junction shed. These engines used the same standard class 4 boiler, but with pressure increased to {{convert|225|psi|abbr=on}} and smaller {{convert|5|ft|3|in|3}} driving wheels and a {{convert|1/2|in|spell=in}} increase in cylinder diameter. This raised their tractive effort to {{convert|31,170|lb}}. Almost unnoticeable was a {{convert|2|in|mm|1|abbr=on}} reduction in [[pony truck]] wheel diameter to {{convert|3|ft|0|in|mm|0|abbr=on}}. Only five engines were ever modified, Nos. 3173, 3156, 3181, 3155 and 3179 which were rebuilt as 3100 to 3104 respectively. All members of the class were scrapped.

==See also==
*[[GWR 5100 Class|GWR 3100/5100 Class (1906)]]
*[[GWR 3150 Class]]
*[[GWR 5101 Class]]
*[[GWR 6100 Class]]
*[[GWR 8100 Class#8100 class|GWR 8100 Class]]
*[[List of GWR standard classes with two outside cylinders]]

==References==
*{{Whitehurst GW Engines from 1940|pages=30, 102, 135}}

== External links == 
*[http://www.railuk.info/steam/getsteamclass.php?item=3100 Class 3100 Details] at ''Rail UK''

{{GWR Locomotives}}

[[Category:2-6-2T locomotives]]
[[Category:Great Western Railway locomotives|3100]]
[[Category:Railway locomotives introduced in 1938]]
[[Category:Scrapped locomotives]]
[[Category:Standard-gauge steam locomotives of Great Britain]]
[[Category:1′C1′ h2t locomotives]]