NER Class B1

NER B1 Class LNER Class N8
LNER N8 class No. 9375 at Hull Dairycotes Locomotive Depot 21 September 1947.
Type and origin Power type Steam Designer Thomas William Worsdell Builder Darlington Works Build date 1886-1890 Total produced 62
Specifications Configuration: ​  • Whyte 0-6-2 Gauge 4 ft 8+1⁄2 in (1,435 mm) Driver dia. 5 ft 1.25 in (1.556 m) Loco weight originally 56 LT 5 cwt (57.2 t) Fuel type Coal Boiler pressure 160 lbf/in2 (1.10 MPa) Cylinders Two, inside Cylinder size originally 18 in × 24 in (457 mm × 610 mm) Valve gear originally Joy
Performance figures Tractive effort 17,265 lbf (76.80 kN)
Career Withdrawn 1929-1956 Disposition All scrapped

The NER B and B1 Classes (later London and North Eastern Railway [LNER] Classes N8) were two classes of 0-6-2 tank locomotives designed by Thomas William Worsdell for heavy freight and mineral on the North Eastern Railway, introduced in 1886. They were tank engine versions of the NER C1 Class 0-6-0, using both simple expansion (Class B1) and also the von Borries configuration for two-cylinder compound locomotives (Class B). Both types were later rebuilt using superheated steam and the compounds were also rebuilt as simple expansion locomotives, and eventually formed a single class (albeit with variations in dimensions). Many of the superheated locomotives were also later returned to saturated steam as their original boilers wore out. As a result the classes have had a very complex mechanical history.