NER 1001 Class
|NER 1001 Class|
|Builder||NER Darlington and Shildon|
|Driver diameter||5 ft 0 1⁄2 in (1.537 m)|
|Wheelbase||11 ft 10 in (3.61 m) locomotive
11 ft 0 in (3.35 m) tender
36 ft 2 in (11.02 m) total
|Axle load||14.1 long tons (14.3 t)|
|Locomotive weight||35.2 long tons (35.8 t)|
|Tender weight||22.1 long tons (22.5 t)|
|Locomotive and tender
|57.3 long tons (58.2 t)|
|Boiler||4 ft 3 in (1.30 m) diameter|
|Boiler pressure||140 psi (0.97 MPa)|
|Firegrate area||13.3 sq ft (1.24 m2)|
|1,229.25 sq ft (114.201 m2)|
|– Firebox||92.5 sq ft (8.59 m2)|
|– Total||1,321.75 sq ft (122.795 m2)|
|Cylinder size||17 in × 26 in (430 mm × 660 mm)|
|Tractive effort||14,750 lbf (65.6 kN)|
|Railroad(s)||North Eastern Railway
London & North Eastern Railway
|Retired||all retired by 1923|
|Disposition||1 preserved (No. 1275), remainder scrapped|
A NER 1001 class locomotive weighed about 35 tons, with a wheelbase of 11 ft 10 in (3.61 m) and 5 ft 0.5 in (1.537 m) diameter driven wheels. Its 4 ft 3 in (1.30 m) diameter boiler produced over 7 tons of tractive effort at 140 psi.
The "long boiler" design dated back to a Stephenson design of 1842. At that time there was a controversy about keeping the centre of gravity low. Another point of view was espoused by John Gray who set out to improve efficiency and increase the pressure in shorter boilers using single drivers instead of coupled wheels. His ideas led to the design of the highly successful Jenny Lind locomotive.
The long boiler design with coupled wheels continued for slower heavier work. A total of 192 NER 1001 class locomotives were built from 1852 by a number of private manufacturers, as well as the NER's own works at Darlington and Shildon.
The small size of the firebox would seem remarkable in later years, but the engines were ideal where trains might spend long periods standing, waiting for a path, or when shunting. A minimum amount of fuel would have delivered sufficient heat to the large boiler to start heavy loads.
The last ten NER 1001's were delivered in 1875. Many were rebuilt in the following twenty five years. The last was withdrawn in 1923.