| Power Classification | 5P |
| Introduced | 1904 – 1912 |
| Designer | Churchward |
| Company | GWR |
| Weight – Loco | 55t 6cwt |
| Tender | 36t 15cwt |
| Driving Wheels | 6ft 8.5ins |
| Boiler Pressure | 200psi superheated |
| Cylinders | Two outside – 18in x 30in |
| Tractive Effort | 20,530lbf |
| Valve Gear | Stephenson (piston valve) |
This was a Churchward 4-4-0 design which used standard components from his 4-6-0 Saint class and were thus a shortened version of the Saint class. They were the last 4-4-0 design introduced on the GWR and were only introduced because the LNWR refused to allow 4-6-0 Saint class locomotives on the joint lines with the GWR.
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Saint class introduced by Churchward in 1902 |
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County class introduced by Churchward in 1904 |
3800 County of Middlesex was completed in May 1904 and was followed by a further nine that year. In 1906 a further twenty were built at Swindon. The last batch of ten appeared in 1911/12.
The last batch built were fitted with superheaters and top feed.
The locomotives were designed for express passenger work.
The design views on the success of the class vary. They were considered to be rough riders they were effective locomotives and completed high mileages in their short lives. 3836 County of Warwick accumulated 1,044,235 miles by the time of its withdrawal from service after a service life of less than 30 years.
The County Class used the same cylinders and motion as Churchward’s six-coupled locomotives, and required the same mass to counterbalance the reciprocating parts of the motion. However the weight required had to be divided between four driving wheels rather than six. The heavier balance weights produced a high level of wheel hammer blow; at 6 revolutions per second the hammer blow was 8 tons, compared with the 3.6 tons of the inside-cylindered City Class and the 6.4 tons of the six-coupled Saint Class.
The 4-4-0 County became the basis of the 4-4-2T design which was introduced
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County class introduced by Churchward in 1904 |
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County tank introduced by Churchward in 1905 |
The first withdrawal from service of one of the locomotives occurred in 1930. All were withdrawn by 1933.
Preserved British Steam Locomotives 