Drehgestells

A Drehgestell, in plural Drehgestelle, is the subframe of a railway vehicle that carries the body and enables riding comfort, stability and guidance along the track. It consists of a rigid or semi-rigid frame that is mounted to the vehicle via a central pivot or bearing, allowing controlled vertical movement and, in some designs, limited yaw. Each Drehgestell typically carries two wheelsets and houses the suspension, braking and, in powered versions, traction elements. In common passenger and freight cars, two Drehgestelle per car are standard.

The main components and functions include the bogie frame, axle boxes and wheelsets, and the suspension system. The wheelsets rotate on bearings within the axle boxes. Primary suspension connects the wheelsets to the bogie frame and often uses coil springs, leaf springs or air springs. Secondary suspension connects the bogie to the vehicle body and provides ride damping and isolation from body motions. Braking equipment is integrated into the Drehgestell, typically with brake cylinders and rigging acting on the wheel rims or discs. In powered bogies, traction motors, gearings and drive shafts transmit propulsion to the wheelsets, sometimes with shaft or cardan connections.

Drehgestelle come in several variants. Most passenger and freight cars use two-axle bogies, while heavier or specialized vehicles may use three-axle designs. Some modern bogies employ steering capabilities to reduce flange wear and track resistance at high speeds. Maintenance focuses on bearing condition, wheel profile, brake components and the integrity of the suspension and pivot points.

Overall, Drehgestelle are essential for vehicle stability, ride quality, weight distribution and track interaction, while enabling safe and efficient motion over railway networks.