The BR 218 locomotive is a diesel locomotive with hydraulic power transmission, a drive type which is widespread in Germany. It is still used today in newly built diesel locomotives in every performance class. In these locomotives, the engine power is transmitted directly via a fluid transmission, drive shaft, and axle gear to the driving wheel. It does not have electric traction motors. Thanks to forgoing electric traction motors, the BR218 is also particularly useable when the use demands especially low electromagnetic effects by the locomotive.
In the BR 218, the transmission and conversion of mechanical energy is achieved with gear trains. Gear wheels, for example in the axle gears of the bogies are used. The large torque of the engine shaft is then transmitted hydrodynamically.
The internal combustion engine of the BR 218 is a V12 or V16 diesel engine producing up to 2400 kW. It is located adjacent to the anteroom of the driver’s cab 1 in a separate section of the locomotive. This engine is started by an electric generator which is located in a separate space. After the diesel engine has ignited, the electric generator takes on the power supply of the locomotive electronics and the charging of the locomotive batteries as an alternator.
The engine exhaust is lead off from the sound suppressor through two ‘scoops’ mounted on the roof of the BR 218 and then outside of the locomotive. These scoops were retrofitted. They must be removed to maintain the UIC505-1 clearance.
The hydraulic gearing takes up the performance of the diesel engine, converts it to about 1500 kW for the drive of the locomotive, and distributes the remaining power to the auxiliary units. Around 400 kW are required for the drive of the heating generator. At the locomotive wheels, effectively around 1300 kW arrive as drive power, determined by the efficiency of the gearing.
The locomotive can switch between transmissions of 140 km/h and100 km/h. The speed range of the respective transmissions is achieved through two gears. The shift point for the fast gear transmission is ~ 90 to 100 km/h with drive position 15.
The hydrodynamic brakes of the gearing allow almost wear-free braking. The hydrodynamic brakes generate only waste heat with high braking power. The locomotive wheels, connected to a pump wheel in the oil-filled gearing, turn against a stationary turbine wheel.
The main braking system of the BR 218 is controlled with compressed air. Each bogie has 4 brake cylinders which bring 2 brake shoes into position per wheel. The air brakes can be combined with the braking power of the hydrodynamic brakes (gearing). Under 45 km/h, only the air brakes are used in the fast gear. The train brakes are triggered from the locomotive via compressed air hoses.
The three-phase synchronous alternator is located on the locomotive side of driver’s cab 2. It produces the electric energy for the attached set of coaches. This heating generator of the BR 218 is responsible for charging the batteries in the coaches, the heating of the train, and all other electric consumers. It is driven by the diesel engine via the gearing and runs at a speed between 1660 and 3000 rpm. It generates approximately 400 kW at 1000 V heating voltage.
The BR 218 is still active today in the Deutsche Bahn AG – previously almost always with n-type coaches, today frequently with modern double-decker coaches.
Select data of the diesel locomotive:
(for information only)
|maximum speed||140km/h; low gear 100km/h|
|continuous tractive effort||175kN|
|tractive effort on starting||235kN|
|multiple traction / feeder train||possible, including doubled power for train line|
|bogie wheel base||2,800mm|
|total wheel base||11,400mm|
|wheel diameter, new||1,000mm|
|wheel diameter, worn||920mm|
|length over buffers||16,400mm|
|distance between bogie pivots||8,600mm|
|width of locomotive body||3,136mm|
|height of locomotive body above top or rail||4,275mm|
|smallest curve radius||100m; Smallest vertical radius concave/convex: 200m|
|type of brake||KE - GPR2 R - H m Z|
|heating train line||AC1000V, 400kVA|
|diesel engine||MTU TB11|
|fuel tank||up to 3,200 litres|