GNR Class J23 - History

History

For shunting and local goods work, the Great Northern Railway (GNR) had traditionally used saddle-tank engines of the 0-6-0 wheel arrangement; the last of these, of GNR Class J13, having been built in 1909 to the designs of H.A. Ivatt, the GNR Locomotive Superintendent.

Nigel Gresley succeeded Ivatt in 1911, and soon identified a need for engines to work the short-haul coal traffic in the West Riding of Yorkshire; the nature of which required that the locomotives also be suitable for shunting. He designed a new class of 0-6-0 tank engine, using side tanks instead of saddle tanks. Gresley had recently begun the rebuilding of the GNR Class L1 0-8-2T locomotives with larger boilers, 4 feet 8 inches (1.42 m) in diameter, which left a number of 4-foot-2-inch (1.27 m) diameter boilers spare. Thirty of these were used in the construction of the new goods tank engines between 1913 and 1919; when ten more were built in 1922, these again used secondhand boilers, but 4 feet 5 inches (1.35 m) in diameter. On the GNR, both varieties were classified J23, but the LNER divided them into J51 with smaller boilers, and J50 with larger boilers. The LNER continued the construction of Class J50, building a further 62 down to 1939, only the first ten of which were given secondhand boilers. Class J51 were rebuilt to class J50 between 1929 and 1935.

Each of the two main classes exhibited variations: locomotive brakes could be operated by vacuum or steam pressure; the driving position could be on the right- or the left-hand side of the cab; and there were three sizes of coal bunker. These variations were recognised by class subdivisions:

• J51/1 10 built 1913–14, 4 ft 2 in boiler, vacuum brake, right-hand drive, short bunker
• J51/2 20 built 1914–19, as J51/1 but long bunker
• J50/1 10 rebuilt 1929–35 from J51/1 with 4 ft 5 in boiler
• J50/2 20 built 1922–24, as J51/2 but 4 ft 5 in boiler, plus 20 rebuilt 1929–34 from J51/1 with 4 ft 5 in boiler
• J50/3 38 built 1926–30, 4 ft 5 in boiler, steam brake, left-hand drive, long bunker
• J50/4 14 built 1938–39, 4 ft 5 in boiler, vacuum brake, left-hand drive, long bunker with hopper

All were built at Doncaster, except the last fourteen which were built at Gorton. Further orders were placed in 1939 and 1941 totalling 25 more locomotives, but these were cancelled in 1942 after a number of components had been manufactured.