| Greases are typically applied in areas where a continuous supply
of oil cannot be retained, such as open bearings or gears.
Factors to be considered when selecting a suitable grease are
operating temperatures, water resistance, oxidation stability etc.
The second factor, not less important, are the grease's
characteristics, including viscosity and consistency. A
lubricating grease consists of a base oil, performance additives and
a thickener which forms a matrix that retains the oil in a semisolid
state. Most grease thickeners are soaps, i.e. lithium, calcium, or
aluminum soap. Complex soap greases have superior temperature
resistance and are commonly usable up to 180ºC, at which the mineral
oil vaporizes. A smaller number of greases, restricted to very
special applications, are manufactured with non-soap thickeners such
as organoclays, polyurea or silica compounds.
Grease is the most widely used lubricant for roller bearings and
low velocity applications, mainly because grease type lubricants
are relatively easy to handle and require only the simplest sealing
devices.
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Why grease lubrication?
Grease
properties