On the calculation of the reduced length of the equivalent pendulum of a cradle suspension of a freight car with inclined suspensions

Abstract

When designing railway rolling stock, design decisions are made to improve its dynamic qualities. They largely depend on vertical and horizontal elastic-dissipative links in the system «wheel pair — bogie frame — body». Reducing the intensity of vertical and horizontal oscillations of the carriage leads to an improvement in the dynamic qualities of the car and an increase in traffic safety. To reduce frame forces, lateral impact from the wheel on the rail between the body and the bogie frame, an elastic connection is provided, implemented by a cradle or pendulum suspension, the rigidity of which is expressed by the reduced length of the equivalent pendulum. To increase the overall safety and reduce the deviation of the direction of the resultant weight of the load from the perpendicular to the floor in curved sections of the track in the cradle suspension, inclined suspensions are used. When analyzing regulatory documents and research results, a difference was established in the formulas used to calculate the reduced length of an equivalent pendulum. The calculated and experimental studies of the dynamic characteristics of the cradle suspension with inclined car suspensions for high-speed freight transportation made it possible to refine the calculation formula.