DB Class E 40

Deutsche Bundesbahn E 40
140 423-5 at Köln-Kalk in October 2007
Type and origin Power type electric Builder Krupp, Henschel, Krauss-Maffei, Siemens, AEG, BBC Build date 1957–1973 (E40.11/139: 1959,1965) Total produced 879
Specifications Configuration: ​  • UIC Bo'Bo' Gauge 1,435 mm (4 ft 8 1⁄2 in) standard gauge Length 16.49 m (54 ft 1 in) Loco weight 83 tonnes (82 long tons; 91 short tons) Electric system(s) 15 kV 16.7 Hz Catenary Traction motors Four Loco brake K-GP mZ, electric brakes (Class 139 only) Train brakes Air Safety systems Sifa, PZB
Performance figures Maximum speed 100 km/h (62 mph) later (110 km/h (68 mph)) Power output 3,700 kW (5,000 hp) Tractive effort 275 kN (62,000 lbf)
Career Operators Deutsche Bundesbahn Deutsche Bahn AG Class E40 / E40.11 (from 1968: 140 / 139)

The Baureihe E 40 is a German Standard electric locomotive (German: Einheits-Elektrolokomotive) commissioned by the Deutsche Bundesbahn in 1955, designed for freight trains. Since the 1968 renumbering, it is listed as Class 140 and Class 139.

In 1950, the Deutsche Bundesbahn introduced two general types of electric locomotives with standardised components: A twelve-wheel (UIC: Co'Co') freight train locomotive as successor for the class E 94 and an eight-wheel (UIC: Bo'Bo') general purpose electric locomotive as successor for the class E 44. A new feature was that the driver was seated, whereas formerly they had to stand.

During the construction period the speed requirement for a general purpose locomotive (working title E 46, then changed to class E 10) was increased to that point that the layout was one for an express train locomotive. Two types were not found sufficient to cover all needs, so the Einheits-Elektrolokomotiven program was changed to four general types: Light passenger train locomotive (class E 41), express train locomotive (class E 10), freight train locomotive class E 40 and heavy freight train locomotive (class E 50). All four classes were designed to share as many components as possible.

The class E 40 basically is a class E 10 without electric brake, altered gear ratio for lower speed and correspondingly higher tractive effort along with additional minor changes.

As all other types of the Einheitslokomotiven program the class E 40 had welded bogies with central pins. Instead the formerly used axle hung motors it used a quill drive with a circular rubber spring as a connecting element ("Gummiringfeder" in German) reducing unsprung mass. The control unit had 28 power settings.

879 units were built, making it the Einheitslokomotive (standard locomotive) of its era.

The original speed was 100 km/h, this was enhanced to 110 km/h in 1969 in order to allow better usability also for commuter trains. A sub-series, known as 140.8, were equipped for push-pull train operation.