The Class 151
The class 151 appeared in 1972 as a further development of the 150 (until 1968: E 50) due to increased performance demands in heavy and fast freight service. Its design was based on the new parameters of the railroad construction and operation regulations (EBO) off 1967, which stipulated freight service speeds of up to 120 km/h / 75 mph and trainloads up to 2,000 tons. These values could only be reached with a locomotive of over 5,000 kilowatts / 6,075 horsepower so that just reworking the class 150 was out of the question right from the start.
Krupp and AEG were responsible for the design of the 151. The proven traction motors from the classes 110 and 140 were selected in the interest of standardization but very new methods of insulation and heat dissipation had to be developed to reach the desired increase in performance. Despite that, the locomotive became so heavy with the necessary new more powerful main transformer and the reinforced resistance brakes that the required axle load could be maintained only with the utmost application of lightweight construction technology. The engineer's cabs were equipped with anatomically correct seats and air conditioning based on the latest technology. Equipping the locomotives with separately mounted buffer beams was obligatory. This enable easy installation of center buffer couplers. The proven trucks for the class 150 were not used and new ones were designed of welded steel lightweight construction. The box support and the wheel set steering by means of Lemniskaten linkage were taken from the class 103. The proven rubber ring spring drive was still used. A 29-step high-voltage relay system with thyristor power circuit breakers now handled control of the traction motor voltage.
Road number 151 001 was the first unit to be delivered on November 21, 1972. By 1977, 170 units had been built at Krupp, Henschel, Krauss-Maffei, AEG, Siemens, and BBC. They were initially used all over West Germany and were even run at times with passenger trains. Road numbers 151 089-122 and in part still have automatic couplers ("Unicoupler") and ran for years mostly in m.u. double-head lashups with heavy ore trains on the routes Hamburg–Beddingen (5,700 tons), Venlo–Dillingen (5,130 tons), and Moers–Linz (3,220 tons). By 2009 after only locomotives from accidents had fallen victim to being removed from service, large numbers of the locomotive were placed in storage due to the economic and financial crisis so that the ranks of these six-axle units sank by half in the last four years. Yet, the class 151 found a new area of activity with private transport companies. The DB subsidiary RBH Logistics GmbH has had 16 units on its roster and five other units have found a new livelihood with other private companies too. The DB will also still need these elegant freight locomotives for several more years. Major overhauls are thus planned in 2014 for them.