The GWR 645 Class was a class of designed by
George Armstrong and built at the
Wolverhampton railway works
Wolverhampton railway works was in the city of Wolverhampton in the county of Staffordshire, England. It was almost due north of the city centre, and is commemorated with a small display of level crossing gates and a plaque. Known as the Staff ...
of the
Great Western Railway (GWR). Thirty-six were constructed between 1872-3, of which three were built for the
South Wales Mineral Railway
The South Wales Mineral Railway was a railway built to serve collieries in the upper Afan Valley, and bring their output to a dock at Briton Ferry, in South Wales. It opened in stages, in 1861 and 1863. It was built on the broad gauge and had s ...
(SWMR), two for the
Carmarthen and Cardigan Railway (C&CR) and the remainder for the GWR. In essence, they were saddle tank versions of his
GWR 633 Class of 1871. From 1878, a further 72 of the class, partially enlarged, were added in the 1501 numbering sequence. Unlike the originals, the "1501"s had full-length saddle tanks from the start.
Construction
The whole class was delivered in nine lots, as follows:
* 645-655, plus one (Lot O, 1872)
* 656, 757-763, plus four (Lot P, 1872-3)
* 764-775 (Lot Q, 1873)
* 1501-1512 (Lot A2, 1878)
* 1513-1524 (Lot B2, 1878-9)
* 1525-1536 (Lot D2, 1879)
* 1537-1548 (Lot E2, 1879–80)
* 1549-60 (Lot F2, 1880)
* 1801-1812 (Lot G2, 1881)
Three of the un-numbered engines plus No. 767 were sold to the SWMR, and the other two plus No. 655 to the C&CR. The latter three returned to the GWR in 1881, becoming Nos. 902-904.
Dimensions
When built, they had
driving wheels (later due to thicker
tyres
A tire (American English) or tyre (British English) is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface over which t ...
) and , or
cylinders. Half-cabs were added a few years after construction. From 1918 all but eight of the class were rebuilt with Belpaire fireboxes and larger, pannier tanks extending over the
smokebox
A smokebox is one of the major basic parts of a steam locomotive exhaust system. Smoke and hot gases pass from the firebox through tubes where they pass heat to the surrounding water in the boiler. The smoke then enters the smokebox, and is e ...
, and the
diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid fo ...
cylinders became standard.
Use
Most of the 645s and 1501s were allocated to the Northern Division of the GWR. Between 1910 and 1922 three more of them, Nos. 1806, 1811 and 1546, were transferred to the SWMR, and others too went to South Wales. Most were withdrawn in 1930s. Nos. 1531, 1532, 1538 and 1542 passed briefly into
British Railways ownership, but all were withdrawn by December 1949. None have survived into preservation.
See also
*
Locomotives of the Great Western Railway
The first Locomotives of the Great Western Railway (GWR) were specified by Isambard Kingdom Brunel but Daniel Gooch was soon appointed as the railway's Locomotive Superintendent. He designed several different broad gauge types for the growing r ...
*
GWR 0-6-0PT
The GWR 0-6-0PT ( Pannier Tank), is a type of steam locomotive built by the British Great Western Railway with the water tanks carried on both sides of the boiler, in the manner of panniers. They were used for local, suburban and branch line passe ...
References
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{{GWR Locomotives
0645
0-6-0ST locomotives
Railway locomotives introduced in 1872
Scrapped locomotives
Mixed traffic locomotives