BNR class NM

Class NM
Type and origin Power type Steam Builder Beyer, Peacock and Company Serial number 6705–6714 Build date 1931 Total produced 10
Specifications Configuration: ​  • Whyte 4-8-0+0-8-4 Gauge 5 ft 6 in (1,676 mm) Driver dia. 4 ft 8 in (1.422 m) Axle load 17.5 long tons (17.8 t) Adhesive weight 138.55 long tons (140.77 t) Loco weight 204.15 long tons (207.43 t) Fuel type Coal Fuel capacity 8 long tons (8.1 t) Water cap. 6,000 imp gal (27,000 L; 7,200 US gal) Firebox: ​  • Grate area 67.6 sq ft (6.28 m2) Boiler pressure 210 psi (1.45 MPa) Heating surface 2,961 sq ft (275.1 m2) Superheater: ​  • Heating area 642 sq ft (59.6 m2) Cylinders Four, outside Cylinder size 20 in × 26 in (508 mm × 660 mm) Valve gear Lentz or Caprotti Valve type Poppet
Performance figures Tractive effort 69,660 lbf (309.86 kN)
Career Operators Bengal Nagpur Railway →Indian Railways Numbers BNR: 826–835 →IR: 38826–38835 Locale East Central Railway zone First run 1931 Last run 1960 Withdrawn 1960 Preserved 0 Scrapped 1960 Disposition Scrapped

The Bengal Nagpur Railway class NM was a class of ten 4-8-0+0-8-4 Garratt locomotives. This was modified N class Garratt. It had Thermic siphon and arch tubes for better performance. It worked on the Bilaspur-Katni line and Anuppur-Chirmiri branch line for hauling coal. Probably because of Poppet valves, they retired early.

Technical specifications
Boiler diameter	7 ft 1+13⁄16 in (2.18 m)
Heating surface of firebox	330 sq ft (31 m2)
Maximum train load	3,000 long tons (3,000 t) on level track

See also

• Indian Railways
• Rail transport in India#History
• Locomotives of India
• Rail transport in India