40
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September - October 2017
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www.machinerylubrication.com
he lubricant is arguably one of
the most essential components
of a machine, but it also happens
to be one of the most vulner-
able. Greatly inf luencing this
vulnerability
is the temperature, which has
an inverse correlation to the most important
lubricant property — viscosity. By becoming
aware of the potential effects that tempera-
ture can have on your lubricants, you can
better
understand how a machine could fail
and hopefully prevent future failures.
Startup Temperature
Star tup temperature is the ambient
temperature upon initial star tup of a
machine before the lubricant has a chance
to reach the operating temperature. During
typical operation, the many contributors
to heat generation such as friction will
cause the temperature to rise and reach
an equilibrium with its surroundings,
also known as the machine's operating
temperature. Knowing a machine's oper-
ating temperature is crucial when selecting
the appropriate lubricant viscosity, since
viscosity has a dependent relationship with
the surrounding temperature.
Cold Machine Starts
The term "cold machine starts" refers
to low ambient temperatures that can be
detrimental to a machine's operability.
The vehicle and mobile equipment indus-
tries have long been developing solutions
for this challenge of dealing with extreme
temperatures, including those in very cold
T
Benne t t Fi t ch
|
Nori a Corpor at ioN
LESSONS IN LUBRICATION
Overcoming the
Machine Starts
of
RISKS COLD
V i s c o s i t y
COLD STARTUP
-20ºC (-4ºF) TO 40ºC
(104ºF)
NORMAL
40ºC (104ºF) TO 80ºC
(176ºF)
EXTREME
ABOVE 80ºC (176ºF)
Monograde
(large rate of change)
Multigrade High VI
(small rate of change)
Multigrade High VI
(smallest rate of change)
VISCOSIT
Y
TEMPERATURE
Lubricant viscosity has a dependent relationship with temperature.
