GWR 2721 Class
Encyclopedia
The GWR 2721 Class was a class of 0-6-0
saddle tank steam locomotive
s. They were designed by William Dean and built at the Swindon Works
of the Great Western Railway
between 1897 and 1901.
They were not a new design, being a straightforward development of the 120-strong 1854 Class
dating back to 1890. This lineage had begun with George Armstrong
's 645 Class
in 1872 and continued via the 1813 Class
(in 1882), the 1854 Class, and finally ended in 1948 with the GWR 9400 Class
. The differences over 76 years were undeniably a gradual evolution, with increases in boiler pressure and heating surface the more important, enclosed cabs and larger bunkers cosmetic but functional. The biggest change was the fitting of a Belpaire firebox
necessitating a pair of pannier tanks, as the square-topped firebox is not compatible with a curved saddle tank. Highlighting the gradual nature of the changes are the subtle differences between the 1854 and 2721 classes, confined to a small increase in wheel size by 1½ inches, fluted rods and coil spring
s all round, at least when new.
When later rebuilt with pannier tanks they were the direct predecessors of the GWR 5700 Class
of 1929. 43 of them survived into British Railways ownership, by which time all had been rebuilt with pannier tanks. Their numbers were 2721-2800 (the last being renumbered 2700 in 1912 to make room for the pioneer 2-8-0
GWR 2800 Class
). Withdrawals started in 1945 and were complete by 1950 by which time the last of the replacement 57xx's (in the 96xx series) were in service.
0-6-0
Under the Whyte notation for the classification of steam locomotives, 0-6-0 represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles, and no trailing wheels...
saddle tank steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...
s. They were designed by William Dean and built at the Swindon Works
Swindon Works
Swindon railway works were built by the Great Western Railway in 1841 in Swindon in the English county of Wiltshire.-History:In 1835 Parliament approved the construction of a railway between London and Bristol. Its Chief Engineer was Isambard Kingdom Brunel.From 1836, Brunel had been buying...
of the Great Western Railway
Great Western Railway
The Great Western Railway was a British railway company that linked London with the south-west and west of England and most of Wales. It was founded in 1833, received its enabling Act of Parliament in 1835 and ran its first trains in 1838...
between 1897 and 1901.
They were not a new design, being a straightforward development of the 120-strong 1854 Class
GWR 1854 Class
GWR 1854 is a class of tank locomotive designed by William Dean and constructed at the Swindon Works of the Great Western Railway. The class used similar inside frames and chassis dimensions to the 1813 Class of 1882-4. In this they differed from the intervening 1661 Class, which had reverted to...
dating back to 1890. This lineage had begun with George Armstrong
George Armstrong (engineer)
George Armstrong was in charge of standard gauge steam locomotives for the Great Western Railway at Stafford Road Works, Wolverhampton from 1864 to 1897...
's 645 Class
GWR 645 Class
The GWR 645 Class was a class of 0-6-0 saddle tank locomotives designed by George Armstrong and built at the Wolverhampton railway works of the Great Western Railway . Thirty-six were constructed between 1872-3, of which three were built for the South Wales Mineral Railway , two for the Carmarthen...
in 1872 and continued via the 1813 Class
GWR 1813 Class
The Great Western Railway's 1813 Class was a series of 40 0-6-0 side-tank engines built at Swindon Works in two lots of 20 engines each:* Nos. 1813-1832 * Nos...
(in 1882), the 1854 Class, and finally ended in 1948 with the GWR 9400 Class
GWR 9400 Class
The Great Western Railway 9400 Class is a class of 0-6-0 pannier tank steam locomotive, used for shunting and banking duties.The first ten 9400s were the last steam engines built by the GWR. After nationalisation in 1948, another 200 were built by private contractors for British Railways...
. The differences over 76 years were undeniably a gradual evolution, with increases in boiler pressure and heating surface the more important, enclosed cabs and larger bunkers cosmetic but functional. The biggest change was the fitting of a Belpaire firebox
Belpaire firebox
The Belpaire firebox is a type of firebox used on steam locomotives. It was invented by Alfred Belpaire of Belgium. It has a greater surface area at the top of the firebox, improving heat transfer and steam production...
necessitating a pair of pannier tanks, as the square-topped firebox is not compatible with a curved saddle tank. Highlighting the gradual nature of the changes are the subtle differences between the 1854 and 2721 classes, confined to a small increase in wheel size by 1½ inches, fluted rods and coil spring
Coil spring
A Coil spring, also known as a helical spring, is a mechanical device, which is typically used to store energy and subsequently release it, to absorb shock, or to maintain a force between contacting surfaces...
s all round, at least when new.
When later rebuilt with pannier tanks they were the direct predecessors of the GWR 5700 Class
GWR 5700 Class
The Great Western Railway 5700 Class is a class of 0-6-0 pannier tank steam locomotive, built between 1929 and 1950. 863 were built, making them the second most-produced British class of steam locomotive.- Overview :...
of 1929. 43 of them survived into British Railways ownership, by which time all had been rebuilt with pannier tanks. Their numbers were 2721-2800 (the last being renumbered 2700 in 1912 to make room for the pioneer 2-8-0
2-8-0
Under the Whyte notation for the classification of steam locomotives, 2-8-0 represents the wheel arrangement of two leading wheels on one axle , eight powered and coupled driving wheels on four axles, and no trailing wheels...
GWR 2800 Class
GWR 2800 Class
The Great Western Railway 2800 Class is a class of steam locomotive designed by G.J. Churchward for heavy freight work. They were the first 2-8-0 class in Great Britain....
). Withdrawals started in 1945 and were complete by 1950 by which time the last of the replacement 57xx's (in the 96xx series) were in service.
See also
- GWR 0-6-0PT – list of classes of GWR 0-6-0 pannier tank, including table of preserved locomotives