Lubricant experts are doing more than ever to make their products less toxic and harmful to everything from the environment to the people using them — which comes with plenty of extra benefits for productivity, too!
Base oils play an important role in determining the performance of an industrial gear oil. They influence characteristics such as low temperature performance,
biodegradability, energy efficiency and high temperature thermal and oxidative stability.
Design and manufacture of gears is among the most complex and difficult disciplines of the industrial arts. From initial conception to machining and
finishing, making gears ain't bean-bag. And guess what? Once those gears roll off the assembly line, it doesn't get any simpler. That's because gears - the metal ones at least - require the correct lubrication in order to prevent - or delay as long as possible - such things as wear, scuffing and Hertzian fatigue.
This paper addresses the lubrication of helical gears - especially
those factors influencing lubricant film thickness and pressure.
Contact between gear teeth is protected by the elastohydrodynamic
lubrication (EHL) mechanism that occurs between nonconforming
contact when pressure is high enough to cause large
increases in lubricant viscosity due to the pressure-viscosity
effect, and changes of component shape due to elastic deflection.
Acting together, these effects lead to oil films that are stiff
enough to separate the contacting surfaces and thus prevent
significant metal-to-metal contact occurring in a well-designed
In order to properly select a grease for a particular application, a sound knowledge of the influence of different grease components and operating conditions on the lubrication supply mechanism and on different failure modes is of great benefit.
This review of elastohydrodynamic lubrication
(EHL) was derived from many
excellent sources (Refs. 1–5). The review of Blok’s flash temperature theory was derived from his publications (Refs. 6–9). An excellent general reference on all aspects of tribology is the Encyclopedia of Tribology (Ref. 10).