Lubricants are substances introduced between moving surfaces to reduce friction and wear. They function by dissolving particles and protecting against damage. Lubricants are typically comprised of 90% base oil, often petroleum, along with additives. They are used to keep parts separated, reduce friction, transfer heat, carry away debris, transmit power, and prevent corrosion. Common types include liquid, solid, and grease lubricants.

2. A LUBRICANT
- (sometimes referred to as "lube") is a substance
(often a liquid) introduced between two moving surfaces
to reduce the friction between them, improving efficiency
and reducing wear.
- have the function of dissolving foreign particles.
Petroleum-based lubricants like Vaseline tend to
dissolve petroleum products such as rubber and plastic;
water-based lubricants will dissolve polar chemicals;
silicone-based lubricants can breakdown silicone toys.

3. - it protects the internal combustion engines in motor vehicle
and power equipments.
- contain 90% base oil (most often petroleum fractions, called
mineral oils) and less than 10% additives. Vegetable oils or
synthetic liquids such as hydrogenated polyolefins, esters,
silicone, fluorocarbons and many others are sometimes used
as base oils.
- -Lubricants are comprised of a base fluid, usually of
petroleum origin, combined with added chemicals that
enhance performance. Base fluids are collected from two
main sources. Refined crude oil or a mixture of chemical
compounds that perform the same task.

4. PURPOSE or FUNCTION OF A
LUBRICANT
•Keep moving parts apart
•Reduce friction
•Transfer heat
•Carry away contaminants & debris
•Transmit power
•Protect against wear
•Prevent corrosion
•Seal for gasses
•Stop the risk of smoke and fire of objects

5. Types of lubricants
- Liquid including emulsions and
suspensions
- Solid lubricants including graphite and
molybdenum disulphide
- Greases (semi-solid)

6. Solid lubricants
Teflon or PTFE
Teflon or PTFE is typically used as a coating layer on, for
example, cooking utensils to provide a non-stick surface.
Mineral
Graphite, hexagonal Boron nitride. Molybdenum disulfide and
Tungsten disulfide are examples of materials that can be used as
solid lubricants, often to very high temperature. The use of such
materials are still restricted by their poor resistance to oxidation
(e.g., molybdenum disulfide can only be used up to 350C in air,
but 1100C in reducing environments).

7. Liquid lubricants
- Lanolin (wool grease, natural water repellant)
Water
-Mineral oils
-Vegetable (natural oil)
* Synthetic oils
-Others
-Note: although generally lubricants are based on
one type of base oil or another, it is quite possible
to use mixtures of the base oils to meet
performance requirements.

9. • They are emulsion of petroleum oils with calcium
soap.
• They are prepared by adding calculated amount of
calcium hydroxide to a hot oil while Under agitation.
The amount of lime can be varied from 10-30% in
calcium-based greases for getting wide range of
consistency from soft paste to hard smooth solid.
• These greases are insoluble in water as a result they
are water resistance. they are Satisfactory use at low
temperature because above 80c,oil and soap begins
to separate Out.
• These greases are suitable for lubricating caterpillar
treads, tractors, water pumps etc.

10. • They are petroleum oil ,thickened by
mixing soaps.
• They sodium soap content is soluble
in water. Hence they are not water
resistance
and can be used upto 175 c.
• They are suitable for use in ball
bearing which generates frictional
heats.

11.  They are petroleum oil , thickened by mixing
lithium soaps.
 These greases are resistance to water and
have good high temperature properties.
• These greases are stable in storage have high
mechanical and oxidation stability.
• They have a melting point about 150 c.
• They are used in aircraft applications at
exchange heights , where temperature as
Low as -55 c may exits.

12. They are prepared by adding lime to resins and
fatty oils .
The mixture is thoroughly mixed and allowed to
stand when grease floats space
as stiff mass.
They are water resistant and suitable for less
delicate equipment working
under high loads and at low speeds.
Talc, mica or any other suitable filler is also
added to them. They are very cheap
resin grease.