Failure Analysis of Idler Gear

Abstract

This paper discusses failure analysis of idler gear. Presently, there is a great challenge in front of automotive industries to overcome failures existing in gears. In order to study failure analysis of gears in industries the present work was planned. Gears have wide variety of applications. They form the most important component in a power transmission system. Their applications vary from watches to very large mechanical units like the lifting devices and automotives. Idler gears generally fail when the working stress exceeds the maximum permissible stress. Advances in engineering technology in recent years have brought demands for idler gear teeth, which can operate at ever increasing load capacities and speeds. The idler gears generally fail when tooth stress exceeds the safe limit. Therefore, it is essential to determine the maximum stress that a gear tooth is subjected under a specified loading. Analysis of idler gears is carried out so that these can be prevented from failure. The causes of these failures are studied. Before testing the mechanical properties, it is essential to understand their structural features as structure is going to govern the properties. This paper also discusses the effect of heat treatment process on micro grain structure of steel in different type furnaces at different temperature levels and varying the holding time and heat treatment mediums. This study shows the effect of heat treatment process (annealing, normalizing, hardening, and tempering) on micro grain structure of steel. By heat treating the steel the material properties like ductility, toughness, hardness, tensile strength can easily be changed which would suit our design. Period of 1 hour soaking used were subsequently cooled by furnace cooling (FC) and iced brine quenching (ICE).