Theoretical and Experimental Working Life Comparison for a Helical Gear under Linear Pitting Failure


Article Preview

For machine components like gears and bearings, working life calculation is one of the complex issues to deal with. This is because the mechanics of their operation is dependent on many parameters, like loading, friction and lubrication etc. Also the influence of these parameters on the component failure modes cannot be perfectly idealized. But in this regard, standards like AGMA (American Gear Manufacturers Association); ISO (International Standard Organization) and BS (British Standards) are quite useful on the basis of which theoretical working life for machine components under a specific failure mode can be predicted. In this paper with linear pitting failure mode assumptions, theoretical working life calculation has been made for a helical gear. BS-ISO 6336-2 standard is used for the gear theoretical life calculations. Furthermore, a wear debris analysis based experiment has been performed for the validation of theoretical calculation. A back to back gear testing rig has been used for the experimental validation. The experimental results show that the theoretical life calculation made on the basis of BS-ISO 6336-2 standards is fairly accurate.



Edited by:

J. Quinta da Fonseca




M. A. Khan and A. G. Starr, "Theoretical and Experimental Working Life Comparison for a Helical Gear under Linear Pitting Failure", Applied Mechanics and Materials, Vols. 7-8, pp. 95-100, 2007

Online since:

August 2007




[1] P.J. Dempsey, Gear damage detection using oil analysis, 14th International congress and exhibition on COMADEM 2001, Manchester United Kingdom.

[2] BS ISO Standard, Calculation of load capacity of spur and helical gears - Calculation of surface durability (pitting), BS ISO 6336-2: (1996).


[3] P.J. Dempsey: Integrating Oil Debris and Vibration measurement for Intelligent machine health monitoring, Report- NASA/TM-2003-211307.

[4] ESDU Standard, The design of helical and spur involute gears, ESDU 88033.

[5] Wear Debris Analysis Handbook, by B.J. Roylance & T. Hunt, Cooxmoor publishing, (1999).