DR series E 77

from Wikipedia, the free encyclopedia
bay. EG 3, Prussia. EG 701–725
DR series E 77
Museum locomotive E 77 10
Museum locomotive E 77 10
Numbering: E 77 01-31
E 77 51-75
Number: 56
Manufacturer: BMAG , BMS, Krauss , LHW
Year of construction (s): 1924-1926
Retirement: 1968
Axis formula : first (1B) (B1), later (1'B) (B1 ')
Gauge : 1435 mm ( standard gauge )
Length over buffers: 16,250 mm
Total wheelbase: 12,100 mm
Service mass: 113.0 t
Friction mass: 77,600 kg
Top speed: 65 km / h
Hourly output : 1880 kW
Continuous output : 1600 kW
Starting tractive effort: 235 kN
Performance indicator: 16.6 kW / t
Driving wheel diameter: 1,400 mm
Impeller diameter: 1,000 mm
Power system : 15 kV 16 Hz AC
Power transmission: Overhead line
Number of traction motors: 2
Drive: Helical rod drive, Winterthur type
Type of speed switch: Electro-pneumatic contactor control with flow dividers
Brake: Air brake
Train brake: Compressed air brake type Knorr

The E 77 series is a series of electric locomotives ordered by the Deutsche Reichsbahn (DR) in 1923 and put into service from 1924. The 56 copies were intended for the routes in the Halle (Saale) - Leipzig area and for the southern German routes.

Pre-war period

The E 77 was intended as a light multi-purpose locomotive in the DR's first type program. The operating program provided for the following transport services:

  • Freight trains with 1,800 tons at 3 per thousand at 30 km / h,
  • Passenger trains with 500 tons to 3 per thousand with 60 km / h,
  • Passenger trains with 500 tons to 10 per thousand with 50 km / h and
  • Freight trains with 850 tons at 10 per thousand at 25 km / h. Later it was mainly used for freight trains. The machines were delivered by BMAG , Krauss and LHW and were originally listed under the regional railway designations EG 3 with the numbers 22 001 to 031 ( Bavarian ) and EG 701 to 725 ( Prussian ). The BMS supplied the electrical part. Originally 37 units of the series were planned, 19 machines were re-ordered. The order for six more locomotives had been canceled.

The E 77 only proved itself to a limited extent in operation. In contrast to the E 91 , which was built according to the same design principles , the E 77 had such poor running characteristics, especially in the range above 55 km / h, that its design was ultimately changed to a single-frame locomotive with the E 75 .

The E 77 was said to have poor running properties in the upper speed range, mechanical connecting elements between the motor bogies often broke, the frames of the motor bogies seemed to be designed too weakly and leaked transformer oil often ignited the wooden floors of the locomotive. There were frequent problems due to the many moving electrical lines. Changes to the chassis did not change anything in this situation, as with the E 91 fixed end axles of the motor bogie, the mobility of the axles was changed, which led to a shorter fixed axle base. When investigating the cause of the poor running of the vehicle, in addition to the higher speed of the E 91, the locomotive is equipped with only one traction motor per motor bogie, which means that the locomotive has a higher center of gravity. Maybe they had crossed with the E 77 a speed range where such a multi-unit locomotive automatically into the rolling device, a speed never reached the E 91st During the Second World War , all machines were exchanged for examples of the E 75 series in the Reichsbahn directorates in Halle and Hanover .

post war period

the museum refurbished E 77.10 2016 for the steam locomotive festival Dresden
E 77.10 2016 in front of a photo freight train in Plauenschen Grund

At the end of the Second World War there were still 53 locomotives. 42 of them, as well as parts of the defective E 77 02, 09, 19, 28, 56, 67, 71 and 73 locomotives were given to the Soviet Union as reparations . The E 77 06 and 51 were so badly damaged that their dismantling in Leipzig was even approved in 1947/48. The E 77 64 was damaged in the war and retired from the network of the later DB. In 1960 Dieter Bäzold took photos of the E 77 05 and another E 77 in Babuschkin near Moscow and a further E 77 driving the superstructure on a circuit. According to an official document from the Ministry of Transport of the USSR, E 77 58 and E 77 75 were still present in Moscow-Babushkin in 1962.

In 1952/53 (without the E 77 05, 58 and 75) 38 of the reparation locomotives returned to the DR fleet . Of these, only the ten with the numbers E 77 03, 10, 14, 15, 18, 24, 25, 30, 52 and 53 were repaired after 1955. The rest were not dismantled until the 1960s. When enough new electric locomotives were available, the E 77 were retired and all vehicles except the E 77 10 were also dismantled by the end of 1966.

The E 77 10 served for a few years as a switch heating locomotive in Halle Hauptbahnhof and was then restored as a museum locomotive in the Dresden-Friedrichstadt depot and then stationed as a mobile museum locomotive in the Dresden-Altstadt Railway Museum, largely returning it to its original state. Its place at the point heating was temporarily taken from 1970 by the E 95 02 until it came to rebuilding honors itself. After it was put back into operation in August 1979, the E 77 10 was given the EDP-compatible company number 204 710. It went through a general inspection after 2013 and can still be experienced as roadworthy (as of 2020).

technical description

View of the driver's cab of the E 77.10, which has been refurbished in a museum

The entire structure of the locomotive is similar to that of the E 91 series , i.e. it consists of two motor bogies, in which the end superstructures are permanently mounted on the motor bogies, and the middle part of the superstructure is the connecting link between the motor bogies via swivel joints. With the exception of the first series of Prussian locomotives (EG 701–713, later E 77 51 to 63), all machines were originally fitted with front wall doors. When the DR put them back into operation, however, the E 77 10 museum locomotive was again given a central transition door with a transition bridge and temporary side protection.

The running axles of the three-part articulated locomotives were initially fixed, later laterally movable with spring return, so that the axle sequence changed from (1B) (B1) to (1'B) (B1 '). But even after the conversion, they were still not satisfied with the smoothness of the vehicles. The installation of a cross coupling between the bogies did not bring the expected smoothness either, they often broke. The Winterthur diagonal side rod drive had a shortened version compared to the E 91. The torque is on a sprung motor pinion to the large wheel of the dummy shaft transmitted.

The main transformer is oil-cooled, its primary and secondary windings are electrically separated. It has 16 taps for the speed steps and two for the electric heating. The locomotive is controlled by an electro-pneumatic contactor control with 15 speed levels. The change of direction of travel is also carried out by a contactor control. A defective motor could be switched off by a special control current switch. The locomotive has two twenty-pole traction motors with a diameter of 2,100 millimeters at the stand. They have a mass of twelve tons and a nominal speed of 626 min −1 .

The pantograph was of the type SBS 9. The Bavarian locomotives had electric train heating, the Prussian ones were prepared for it.

literature

  • Horst J. Obermayer: Paperback German electric locomotives . Franckh'sche Verlagshandlung, Stuttgart 1970, ISBN 3-440-03754-1 .
  • Dieter Bäzold, Günther Fiebig: Electric Locomotives of German Railways (=  Railway Vehicle Archive . No. 4 ). 1st edition. Alba, Düsseldorf 1984, ISBN 3-87094-093-X (Licensed edition of the Transpress-Verleges für Verkehrwesen, Berlin for the Federal Republic of Germany, Berlin (West), Austria and Switzerland. 5th edition. Transpress Verlag, Berlin 1984).
  • Bernd Beck: The Wechmann plan. Electric standard locomotives for the DRG (=  Eisenbahn-Kurier . No. 10 ). EK, Freiburg 2016.
  • Oliver Strüber: E 77 series. In Bavaria and Prussia. In: Lok Magazin , 4/2019, April, pp. 76–87.

Web links

Commons : DRG series E 77  - collection of images, videos and audio files

Individual evidence

  1. a b c d Bernd Beck: The Wechmann Plan -Electric standard electric locomotives for the DRG (=  Eisenbahnkurier . No. 10 ). EK-Verlag, Freiburg 2016.
  2. Dieter Bäzold, Günther Fiebig: Electric Locomotives of German Railways (=  Railway Vehicle Archive . No. 4 ). 1st edition. Alba, Düsseldorf 1984, ISBN 3-87094-093-X (Licensed edition of the Transpress-Verleges für Verkehrwesen, Berlin for the Federal Republic of Germany, Berlin (West), Austria and Switzerland. 5th edition. Transpress Verlag, Berlin 1984).
  3. Peter Glanert, Thomas Borbe, Wolfgang-Dieter Richter: Reichsbahn-electric locomotives in Silesia. Development, use and whereabouts from 1909 until today . VGB, Fürstenfeldbruck 2015, ISBN 978-3-8375-1509-1 , p. 233 .