Axle box bearing In the axle box of an electric freight locomotive, two rolling bearings are installed to support a traction motor arranged horizontally. The traction motor is directly suspended on the axle through the hug bearing. In order to achieve a long service life (the basic rating life exceeds two million kilometers), roller bearings with high load carrying capacity are selected. The tapered roller bearing is used in the axle holding box of railway vehicles, which is especially suitable for bearing high radial and axial loads, and is beneficial to realize the precise guidance of the gear axis. Special tapered roller bearings with reinforced steel plate cages can withstand high vibration and shock loads. Cylindrical roller bearings can withstand high radial loads and are easy to install. Spherical roller bearings are preferentially used in occasions that bear high radial and bidirectional axial loads and require good self-aligning functions.