Most sugar cane crushing mills rely on the satisfactory performance of several trains of
reduction gears. Among these are the slower speed drive gears which are generally of
the open type, i.e., not enclosed in a scaled gearcase. Because of their open
configuration, these gears are commonly lubricated with a viscous, adherent type of
lubricant containing a high percentage of solids such as molybdenum disulphide and
graphite. Whereas significant tribological analysis has been carried out on enclosed
gears lubricated by a recirculating oil, very little attention had been given to open gears.
This paper considers the application of current lubrication theories, such as
elastohydrodynamics, to open gears and correlates these with field experience.
Comparisons are made between the operational requirements of the sugar mill gears and
those of open gears in other machines such as draglines and cement mills. The operating
conditions for open gears have been examined and special tests conducted.
Environmentally friendly products have been shown to vary widely in performance
from very good to poor.