Experimental study of starvation in grease-lubricated finite line contacts
Abstract
Purpose
The purpose of this paper is to study starvation in grease-lubricated finite line contacts and to understand film-forming mechanisms of grease-lubricated finite line contacts.
Design/methodology/approach
A multiple-contact optical elastohydrodynamic (EHL) test rig is constructed to investigate the influences of lubricant properties on film thickness and lubrication conditions at different working conditions. The film thickness is calculated according to the relative light intensity principle. The degree of starvation is evaluated by the air–oil meniscus distance and the corresponding film thickness.
Findings
The experimental results show that for greases with high-viscosity base oil, the high-frequency fluctuation of film thickness is observed in low-speed operating conditions. Reducing the viscosity of the base oil and improving running speed can weaken the fluctuation of film thickness. The degree of starvation increases with increasing base oil viscosity, rolling speed and the crown drop. In addition, reducing the replenishment time by reducing the gap between the rollers also can increase the degree of starvation.
Originality/value
Starvation is often to occur in finite line contacts, such as roller bearings and gears; there are still limited finite line contact EHL test rigs, much less multiple-contact optical test rigs. Therefore, the present work is undertaken to construct the multiple-contact test rig and to evaluate the mechanism of starvation in finite line contacts.
Keywords
Acknowledgements
This study was supported by the National Twelfth-Five Years’ Projects of China for Science and Technology under Contract D50-0109-12-001 and the Key Innovational Program of Shanghai Municipal Education Commission (No. 11ZZ89).
Citation
Wang, Z., Shen, X., Chen, X., Han, Q. and Shi, L. (2017), "Experimental study of starvation in grease-lubricated finite line contacts", Industrial Lubrication and Tribology, Vol. 69 No. 6, pp. 963-969. https://doi.org/10.1108/ILT-08-2017-0235
Publisher
:Emerald Publishing Limited
Copyright © 2017, Emerald Publishing Limited