Applications of Solid Lubrication Review
Applications of Solid Lubrication. Generally,
solid lubricants are used in applications not tolerated by
more conventional lubricants. The most common conditions
requiring use of solid lubricants are:
(1) Extreme temperature and pressure
conditions. These are defined as high-temperature
applications up to 1926C ( 3500F), where other
lubricants are prone to degradation or decomposition;
extremely low temperatures, down to -212C (-350F), where
lubricants may solidify or congeal; and high-to-fullvacuum
applications, such as space, where lubricants may
(2) As additives. Graphite, MoS2
, and zinc oxide are frequently added to fluids and greases.
Surface conversion coatings are often used to supplement
(3) Intermittent loading conditions. When
equipment is stored or is idle for prolonged periods, solids
provide permanent, noncorrosive lubrication.
(4) Inaccessible locations. Where access for
servicing is especially difficult, solid lubricants offer a
distinct advantage, provided the lubricant is satisfactory
for the intended loads and speeds.
(5) High dust and lint areas. Solids are
also useful in areas where fluids may tend to pick up dust
and lint with liquid lubricants; these contaminants more
readily form a grinding paste, causing damage to equipment.
(6) Contamination. Because of their solid
consistency, solids may be used in applications where the
lubricant must not migrate to other locations and cause
contamination of other equipment, parts, or products.
(7) Environmental. Solid lubricants are
effective in applications where the lubricated equipment is
immersed in water that may be polluted by other lubricants,
such as oils and greases.