BNR class N

The Bengal Nagpur Railway class N Garratt was a class of steam locomotives built by Beyer, Peacock & Co. in 1929. At the time of their construction, they had the largest water capacity of any Garratt, in addition to being the largest locomotives in India. With the success of HSG, this class followed. Due to their heavy weight, they were restricted to 90 lb/yard rails. They had straight-ported cylinders. It is not known if this suited them for hauling slow, heavy coal traffic. Like HSG, they were used Chakradharpur-Jharsuguda and also at Anara-Tatanagar sections. After electrification, they were used at Rourkela. They could haul 2400 tonnes on a 1 in 100 gradient.[1]

BNR class N
Preserved unit at National Rail Museum, Delhi
Type and origin Power type Steam Builder Beyer, Peacock & Co. Serial number 6583–6598 Build date 1929 Total produced 16
Specifications Configuration: ​  • Whyte 4-8-0+0-8-4  • UIC (2′D)(D2′) h4t Gauge 5 ft 6 in (1,676 mm) Driver dia. 4 ft 8 in (1.422 m) Axle load 20.25 long tons (20.57 t) Adhesive weight 159.4 long tons (162.0 t) Loco weight 234 long tons (238 t) Fuel type Coal Fuel capacity 14 long tons (14 t) Water cap 10,000 imp gal (45,000 l; 12,000 US gal) Firebox:  • Firegrate area 69.8 sq ft (6.48 m2) Boiler pressure 210 psi (1.45 MPa) Superheater: ​  • Heating area 642 sq ft (59.6 m2) Cylinders Four, outside Cylinder size 20 1⁄2 in × 26 in (521 mm × 660 mm) Valve gear Walschaerts Valve type Piston valves
Performance figures Maximum speed 45 mph (72 km/h) Tractive effort 69,655 lbf (309.84 kN)
Career Operators Bengal Nagpur Railway →Indian Railways Numbers BNR: 810–825 →IR: 38810–38825 Locale South Eastern Railway zone First run 1929 Last run 1970 Retired 1970 Withdrawn 1970 Preserved No. 811 and 815 Current owner National Rail Museum, Delhi and Kharagpur Workshops

In 2006 Locomotive 811 at Kharagpur workshop was reactivated and used on a few runs before being stored again. In order to activate the locomotive, many parts were borrowed from locomotive 815 at the Delhi Railway Museum. The parts were later returned and refitted to 815 which itself was given a cosmetic overhaul. In 2018 a second attempt to activate 811 was made. This time all missing parts were fabricated in a US$400,000 refurbishment that was put out to public tender. The locomotive has made just one trial trip up to the end of 2019.