GWR 3252 Class

The Great Western Railway 3252 Class, or better known as "Duke" Class were a class of 4-4-0 steam locomotives with outside frames and parallel domed boilers. They were built in five batches between 1895 and 1899 for express passenger train work in Devon and Cornwall. William Dean was their designer, possibly with the collaboration of his assistant, George Jackson Churchward. Four prototype 4-4-0s, of the Armstrong Class, had already been built in 1894.
==Design==
===Frames and wheels ===
The outside frames of the Dukes were curved upwards over each pair of driving wheels. Inner and outer frames were 3⁄4 in (19 mm) thick. The first 40 members of the class were fitted with Mansell pattern bogie wheels with wooden centers. The first 25 tenders built also had Mansell pattern wheels, and a shorter than normal wheelbase of 11 ft (3.35 m) so that the locomotives would fit on the smaller turntables then in use west of Newton Abbot. The engine bogie was of a center-less type designed by Dean
===Boilers===
The majority of the class were fitted with round-topped fireboxes of the same diameter as the boiler. The last four were fitted with Belpaire fireboxes, raised a few inches above the boilers. Eighteen of the Duke class were later rebuilt with domeless tapered boilers and Belpaire fireboxes between October 1906 and January 1909. They were reclassified as members of the Bulldog Class. A further Duke, no. 3273 Armorel, had been fitted with a parallel domeless boiler in February 1902, converting it to a Camel Class locomotive. It was fitted with a Bulldog-type boiler in October 1910. By December 1923 all remaining Dukes had been fitted with flush-topped Belpaire fireboxes and domed boilers pressed to 180 lbf/in2 (1.2 MPa) Duke no. 3258, King Arthur, built August 1895, was fitted with a superheater in December 1896. The rest of the class, with the exception of two locomotives, were fitted with superheaters between August 1911 and September 1946. The class had distinctive long smokeboxes, extended to hold a diaphragm plate and net for spark prevention.
===Cylinders and valves ===
Slide valves were fitted underneath the cylinders, and were driven directly by eccentrics on the leading driving axle through Stephenson valve gear. This position had the advantage that, when the regulator was closed and steam pressure shut off, the valves would drop away from the steam ports, thus reducing wear on the valves and port faces. Dean's earlier designs had used slide valves mounted vertically between the cylinders; the new position allowed an increase in cylinder diameter from 17 in (432 mm) to 20 in (508 mm) in the Armstrong Class. The Dukes had 18 in (457 mm) diameter cylinders, possibly due to permanent way weight restrictions and a reduced supply of steam from the Dukes' smaller boilers.
Table of orders and numbers
Year 	Quantity	Lot No.	Works No.	Locomotive numbers	Notes
1895 	2 	97 	1431–1432	3252–3253 	
1895 	8 	101 	1493–1500	3254–3261 	
1896 	10 	102 	1501–1510	3262–3271 	
1896–97	20 	105 	1531–1550	3272–3291 	
1898–99	20 	113 	1682–1701	3312–3331 	
==Renumbering==
The Dukes were subject to the 1912 renumbering of GWR 4-4-0 locomotives. Those Dukes rebuilt as Bulldogs were renumbered as members of that class in the series 3300–3455. The remaining Dukes were renumbered consecutively as 3252–3291, this block of numbers having previously been allocated to the first batch of Duke Class locomotives.
==Rebuilding==
By the 1930s many of the Duke class were becoming uneconomical to repair, particularly with regard to the curved outside frames, which were weaker than the later straight-topped version. A number of the class had been transferred to the ex-Cambrian Railways main line, where permanent way restrictions debarred the use of heavier locomotives.
In December 1929, no. 3265, Tre Pol and Pen, was withdrawn, and the cylinders and motion, together with a spare Duke boiler and smokebox, were fitted to the straight-topped frames and cab of Bulldog no. 3365 Charles Grey Mott. The rebuilt locomotive retained the name and number of the Duke. The reduction in axle weight, as compared to the Bulldogs, allowed for working over the Cambrian section.
From 1936 a further twenty-nine of the Dukes were withdrawn and replaced by Bulldogs fitted with Duke boilers and motion, reclassified as Earl Class locomotives. The onset of World War II brought a halt to the program, the last replacement being in November 1939, leaving ten Dukes to pass into British Railways ownership. These were scrapped between June 1949 and July 1951, the last survivor being No. 9089, formerly no. 3289 St Austell of July 1899. 
No Dukes were preserved; however, the boiler of No. 3282 (originally named 'Chepstow Castle') survives on Earl No. 9017 'Earl of Berkeley' at the Bluebell Railway. 
==In fiction==
The fate of the Dukes are mentioned by Duck the Great Western Engine in the Reverend Wilbert Awdry's children's book Very Old Engines.
==Summary table==
Numbers	Numbers 	Numbers 	Names 	Names
First 	Second 	Third 	First 	Second
3252 	3252 	Earl 3214	Duke of Cornwall	
3253 	Bulldog 3300	 	Pendennis Castle	
3254 	3253 	Earl 3223	Boscawen 	
3255 	3254 	9054 	Cornubia 	
3256 	3255 	Earl 3205	Excalibur 	
3257 	3256 	Earl 3228	Guinevere 	
3258 	3257 	Earl 3213	King Arthur 	Denamed in 1927
3259 	3258 	Earl 3217	Lizard 	The Lizard
3260 	3259 	Earl 3221	Merlin 	
3261 	3260 	Earl 3219	Mount Edgcumbe 	
3262 	Bulldog 3301	 	Powderham 	
3263 	Bulldog 3302	 	Sir Lancelot 	
3264 	Bulldog 3303	 	St. Anthony 	
3265 	3261 	Earl 3212	St. Germans 	
3266 	3262 	Earl 3215	St. Ives 	
3267 	3263 	Earl 3201	St. Michael 	
3268 	Bulldog 3304	 	Tamar 	River Tamar
3269 	Bulldog 3305	 	Tintagel 	
3270 	3264 	9064 	Trevithick 	
3271 	3265 	Earl 3265	Tre Pol and Pen 	
3272 	3266 	Earl 3218	Amyas 	
3273 	Bulldog 3306	 	Armorel 	
3274 	3267 	Earl 3206	Cornishman 	
3275 	3268 	Earl 3225	Chough 	
3276 	3269 	Earl 3210	Dartmoor 	
3277 	3270 	Earl 3226	Earl of Devon 	Denamed in 1930
3278 	3271 	Earl 3204	Eddystone 	
3279 	Bulldog 3307	 	Exmoor 	
3280 	Bulldog 3308	 	Falmouth 	
3281 	3272 	9072 	Fowey 	Denamed in 1930
3282 	Bulldog 3309	 	Maristowe 	
3283 	3273 	9073 	Mount's Bay 	
3284 	3274 	Earl 3207	Newquay 	Denamed in 1930
3285 	3275 	Earl 3203	St. Erth 	Denamed in 1930
3286 	Bulldog 3310	 	St. Just 	
3287 	3276 	9076 	St. Agnes 	Denamed in 1930
3288 	3277 	Earl 3209	Tresco 	Isle of Tresco
3289 	3278 	Earl 3222	Trefusis 	
3290 	3279 	Earl 3220	Torbay 	Tor Bay
3291 	3280 	Earl 3227	Tregenna 	Denamed in 1930
3312 	Bulldog 3311	 	Bulldog 	
3313 	3281 	Earl 3211	Cotswold 	
3314 	3282 	Earl 3216	Chepstow Castle 	Denamed in 1930
3315 	3283 	9083 	Comet 	
3316 	Bulldog 3312	 	Guernsey 	Isle of Guernsey
3317 	3284 	9084 	Jersey 	Isle of Jersey
3318 	Bulldog 3313	 	Jupiter 	
3319 	3285 	Earl 3208	Katerfelto 	
3320 	3286 	Earl 3202	Meteor 	
3321 	3287 	9087 	Mercury 	
3322 	Bulldog 3314	 	Mersey 	
3323 	3288 	Earl 3200	Mendip 	
3324 	Bulldog 3315	 	Quantock 	
3325 	Bulldog 3316	 	St. Columb 	
3326 	3289 	9089 	St Austell 	Denamed in 1930
3327 	Bulldog 3317	 	Somerset 	
3328 	3290 	Earl 3224	Severn 	
3329 	3291 	9091 	Thames 	
3330 	Bulldog 3318	 	Vulcan 	
3331 	Bulldog 3319	 	Weymouth 	
==Gallery==
File:GWR 3258 King Arthur at Brent.jpg|3258 King Arthur
Category:4-4-0 steam locomotives
Category:4-4-0 locomotives
Category:Locomotives That were Involved in Rebuilds
Category:Great Western Railway locomotives
Category:Scrapped locomotives
Category:GWR 3252 "Duke" Class
Category:Dean locomotives
Category:4 foot 8 1⁄2 inch gauge
Category:British locomotives
Category:Standard gauge locomotives
Category:Steam locomotives
Category:Standard gauge steam locomotives of Great Britain
Category:Locomotives
Category:Tender locomotives
Category:Swindon Works locomotives
Category:Built in 1895
Category:Built in 1896
Category:Built in 1897
Category:Built in 1898
Category:Built in 1899
Category:Scrapped steam locomotives