British Rail Class 31

Brush Type 2
British Rail Class 31

31108 and 31190 at Sutton Cross (NVR)

Type and origin Power type Diesel-electric Builder Brush Traction Serial number 71–90, 119–178, 180–280, 282–326, 362–398 Build date 1957–1962 Total produced 263

Specifications Configuration A1A-A1A UIC class (A1A)(A1A) Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge Wheel diameter Driving: 3 ft 7 in (1,092 mm) Idling: 3 ft 3 1⁄2 in (1,003 mm) Minimum curve 4.5 chains (300 ft; 91 m) Wheelbase 42 ft 10 in (13.06 m) Length 56 ft 9 in (17.30 m) Width 8 ft 9 in (2.67 m) Height 12 ft 7 in (3.84 m) Loco weight 106.7 long tons (108.4 t; 119.5 short tons) to 113 long tons (115 t; 127 short tons) Fuel capacity 650 imp gal (3,000 l; 780 US gal) Prime mover Original: Mirrlees JVS12T Rebuilt: English Electric 12SVT Traction motors Four DC traction motors Transmission Diesel electric Train heating 31/0 & 31/1: Steam 31/4: Electric Train Heat Train brakes Vacuum / Dual (Air/Vac)

Performance figures Maximum speed D5500–5534: 80 mph (129 km/h) Remainder: 90 mph (145 km/h) Power output Engine: Mirrlees: 1,250 bhp (930 kW) or 1,365 bhp (1,018 kW) English Electric: 1,470 bhp (1,100 kW) At rail: 1,170 hp (870 kW) Tractive effort Maximum: 35,900 lbf (159,691 N) Loco brakeforce 49 long tons-force (488 kN)

Career Operators British Railways Numbers D5500–D5699, D5800–D5862, later 31001–31970 Axle load class Route availability 5 or 6

The British Rail Class 31 diesel locomotives, also known as the Brush Type 2 and originally as Class 30, were built by Brush Traction from 1957-62.

Construction of the first locomotive was completed in the final week of September 1957, and the handing-over took place on 31 October. The Class 31 entered service in November 1957, after the launch of the Class 20 locomotive and was one of the Pilot Scheme locomotives ordered by British Railways to replace steam traction.

They were originally built with Mirrlees JVS12T 1,250 bhp (930 kW) (D5500–D5519) and 1,365 bhp (1,018 kW) engines and Brush electrical equipment, but the engines were not successful and in 1964 D5677 was fitted with an English Electric 12SVT engine (as used in the Class 37) de-rated to 1,470 bhp (1,100 kW). The trial proved successful, and between 1965 and 1969 the entire class was re-engined. The de-rated engine was used as it was the maximum the electrical system could accept.

The Mirrlees-engined locomotives were originally known as Class 30 under TOPS, with re-engined examples joining Class 31. The class was originally intended for service on the Eastern Region, but gradually became common in both the Western and London Midland regions too.

Several sub-classes of Class 31 exist:

These first 20 locomotives, originally numbered D5500–D5519, were always easily recognisable as they did not have the headcode box mounted on the roof above the cab, leading to the nickname "Skinheads". They were also nicknamed "Gurglers" from the noise of their engines, and "Toffee Apples" from the shape of the control key which had to be taken from cab to cab when changing ends. These pilot scheme locomotives were non-standard in having Electro-Magnetic Multiple-Working control equipment, and were limited to 80 mph (130 km/h). After being involved in a serious collision D5518 was rebuilt in September 1967 as a standard locomotive, with indicator boxes, and blue star coupling code