Modal analysis of prestressed draft pad of freight wagons using finite element method

Sachin Sudhakar Harak,Suraj Prakash Harsha,Satish Chand Sharma

doi:10.1007/s40534-014-0064-9

Sachin Sudhakar Harak, Suraj Prakash Harsha + Show 1 more

Open Access

https://doi.org/10.1007/s40534-014-0064-9

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Abstract

The present work intends to investigate dynamic behaviour of draft gear using finite element method. The longitudinal force that the draft gear absorbs usually leads to the failure of its components, especially, the load bearing draft pads. Dynamic behaviour of an individual draft pad and a draft gear is determined and characterized with exciting frequencies and corresponding mode shapes. The effect of compressive prestress load on the dynamic behaviour of an individual draft pad is also determined as the draft pads in assembled state are under constant axial compressive force in the draft gear. The vibration characteristics of individual draft pad are compared with draft pads that are part of draft gear. The modal analysis gives us a basis for subjecting a draft pad to higher frequency loading for determining its fatigue behaviour.

Highlights

In longitudinal train dynamics, draft gear is the most important component of the autocoupler
The effect of compressive prestress load on the dynamic behaviour of an individual draft pad is determined as the draft pads in assembled state are under constant axial compressive force in the draft gear
The vibration excitation of an individual draft pad has been compared with the dynamics of draft pads in the draft gear for identifying various frequencies for a given mode shape

Summary

Introduction

Draft gear is the most important component of the autocoupler. Chen [5] proposed a mathematical model to calculate transient responses of the coupler, whereas McClanachan et al [6] conducted experiments to determine the occurrences of coupler impacts combined with pitching motions in the wagon body. These interactions were simulated using NUCARS, ADAMS/Rail and a train-wagon interaction model. Nasr and Mohammadi [8] studied the effect of train braking delay time on train longitudinal dynamics. They carried out simulations for three different. The vibration excitation of an individual draft pad has been compared with the dynamics of draft pads in the draft gear for identifying various frequencies for a given mode shape

FE analysis

Individual draft pad

Model for modal analysis

Results

Conclusions