Root cause failure analysis of a tracked vehicle balance arm

Ayaz M Khan,Khalid Mahmood,Syed Waheed Ul Haq,Rizwan Saeed Choudhry,Shahbaz Mahmood Khan

doi:10.1016/j.csefa.2017.10.001

Abstract

This paper relates to an upgraded Industrial tracked vehicle which was found with a failed Balance arm during disassembly. The failure analysis of an actual Balance Arms surface was carried out using Fractography and Non Destructive testing techniques to dig out the root cause. The analysis revealed microscopic signatures categorically pointing towards post failure surface mechanical damage. The factor causing to promote failure was improper manufacturing i.e. casting which was further attributed to MnS inclusions.

Highlights

Suspension system plays a vital role in stability of a Tracked vehicle especially under dynamic loading
As the tracked vehicle is generally subjected to severe loading conditions, it is of high likelihood that its critical assemblies may fail or develop fatigue cracks
The single fractured balance arm during tracked vehicles disassembly was visually examined to know the probable cause of failure/damage

Summary

Introduction

Suspension system plays a vital role in stability of a Tracked vehicle especially under dynamic loading. It is used to lessen the shock of ground against the hull transmitted through the tracks and road wheels during the vehicles running's and decay the vehicle vibration and ensuring smooth running of the vehicle To fulfil these requirements, four major parts i.e. Balance arms, torsion bars, shock absorbers, upper and lower bump stops are present. This study is focused towards ascertaining the effect of added weight on the tracked vehicle Balance arms and find out the failure root cause. It is important to note that, the rebuild cycles of the tracked vehicle discussed in the present study are scheduled for every 9000 km track running, but the Arms of the upgraded vehicles (with body weight enhancements) were found either fractured or had produced cracks after only 5320 km running. To the best of authors knowledge there is no such study reported in International Journals of repute

Methods

Results

Conclusion