Application of different types of motor-axle bearings of locomotive wheel-motor units in the Far North

Abstract

   Improvements in locomotive wheel-motor unit (WMU) design over the last decade have been made in terms of the transition to rolling motor-axle bearings (MAB) instead of plain bearings, which was the basis for the proposed study.   The study is aimed to provide a theoretical estimation of power losses in different types of locomotive WMU MAB and its validation depending on heating temperature and bearing specifications.   The study is aimed to determine power losses in MABs using new approaches to their determination.   New methods of determining the power losses in the plain and rolling MABs of locomotive WMUs are suggested. These methods allow calculating the values of power losses depending on the specifications of MAB and its heating temperature. Depending on the bearing heating temperature, recommendations are provided with regard to operating conditions of a particular type of locomotive WMU bearing. It is recommended to operate motor-axle plain bearings in the temperature range of 10 to 20 °C, and rolling bearings from 20 °C and above. The suggested methodologies for calculating power losses of locomotive WMU MABs can be used to determine the energy efficiency of a given drive type, taking into account the type of the grease, its temperature, design features and operating conditions. The obtained results can serve as recommendations for the selection of the type of MAB.