Lubrication is the science and practice of minimizing friction and wear between moving surfaces by introducing a lubricant—a substance that forms a protective film—between them. Whether it’s the engine in your car or the gears in industrial machinery, proper lubrication is essential for efficient operation. Key Functions of Lubricants: Friction Reduction: Lubricants create a slippery layer, allowing smoother motion and reducing the resistance between surfaces. Wear Prevention: By preventing direct metal-to-metal contact, lubricants minimize wear and extend the lifespan of components. Heat Dissipation: During sliding or rolling, lubricants absorb and dissipate heat generated, preventing overheating. Corrosion Protection: Lubricants shield surfaces from environmental factors that cause corrosion. Types of Lubricants: Liquid Lubricants: Oils and greases are common liquid lubricants. They flow easily and fill gaps between surfaces. Solid Lubricants: Materials like graphite, molybdenum disulfide (MoS₂), and polytetrafluoroethylene (PTFE) act as solid lubricants. Boundary Lubrication: Thin films at surface asperities provide protection. Hydrodynamic Lubrication: Full fluid film separation due to relative motion.

1. JNTUH UNIVERSTY COLLEGE OF ENGINEERING SULTANPUR
LUBRICANTION AND TRIBIOLOGY
Presented by:
M . G. A. V. Srikanth
(22SS1A0336)

2. Index
 INTRODUCTION.
 LUBRICANTS
 TRIBOLOGY
 FACTORS AFFECTING LUBRICATION
 APPLICATIONS OF LUBRICANTS AND TRIBOLOGY
 CONCLUSION

3. Historical background of lubrication and tribology
 The history of lubrication and tribology dates back to ancient times, where early humans used animal fats, vegetable oils, and waxes to reduce
friction between rubbing surfaces. The ancient Egyptians used animal fat as a lubricant to reduce the friction of sleds carrying large stones, while the
Greeks used olive oil to lubricate chariot wheels.
 In the Middle Ages, tallow and lard were used to lubricate gears and bearings in mills and water wheels. The industrial revolution in the 19th century
marked a significant development in lubrication technology, with the invention of steam engines and machines requiring high-performance lubricants.
Mineral oils became the preferred lubricants for their improved stability, lubricity, and ability to withstand high temperatures.
 The field of tribology emerged in the mid-20th century as a multidisciplinary science combining engineering, physics, and chemistry to study the
interaction between surfaces in relative motion. The term "tribology" was coined by Peter Jost in 1966, derived from the Greek word "tribos,"
meaning rubbing.
 Advancements in materials science and lubricant technology have led to the development of new lubricants and coatings for a wide range of
applications, including automotive, aerospace, and medical industries. Today, lubrication and tribology play a crucial role in maintaining the
performance and durability of machinery, and research continues to improve lubrication efficiency and reduce wear and energy consumption.
INTRODUCTION

4. Definition of lubrication and tribology
 Tribology and Lubrication Technology are most important applications for
industry to maintain higher level of maintenance and process operation in
machinery and equipment. Tribology comprises of the science and technology
of interacting surfaces in relative motion; that is, friction, lubrication and
wear. Condition Monitoring based on wear debris analysis of used oil is
considered as a tool which can quickly identify the health of machinery and
diagnose the same before breakdown. The course on Tribology and Lubrication
Technology will provide the foundational skillset for applying Tribology
practices. Through this course, the Participants will be able to use the best
practices for selecting, storing and testing lubricants to boost reliability and
generate lasting results in machine equipment, efficiency/ maintenance. They
will also gain better understanding of oil analysis, so as to align their efforts
with those of maintenance professionals.
INTRODUCTION

5. Definition of lubrication and tribology
 The primary purpose of lubrication is to reduce wear and heat between
contacting surfaces in relative motion. While wear and heat cannot be
completely eliminated, they can be reduced to negligible or acceptable
levels. Because heat and wear are associated with friction, both effects
can be minimized by reducing the coefficient of friction between the
contacting surfaces. Lubrication is also used to reduce oxidation and
prevent rust; to provide insulation in transformer applications; to transmit
mechanical power in hydraulic fluid power applications; and to seal against
dust, dirt, and water.
INTRODUCTION

6. Importance of lubrication and tribology in mechanical systems
• Lubrication and tribology play a critical role in ensuring the efficient and reliable operation of mechanical systems. Here are
some of the key reasons why they are important:
• Reducing friction and wear: Lubrication helps to reduce friction and wear between surfaces in relative motion, which can
cause damage, heat generation, and reduced efficiency. Proper lubrication can extend the lifespan of machinery and reduce
maintenance costs.
• Energy efficiency: By reducing friction, lubrication can improve the energy efficiency of mechanical systems by reducing the
amount of energy lost to heat and increasing the mechanical output.
• Corrosion prevention: Lubricants can also provide a protective barrier against corrosion and rust, which can occur due to
moisture and other environmental factors.
INTRODUCTION

7. Importance of lubrication and tribology in mechanical systems
 Noise reduction: Lubricants can help to reduce noise and vibration in mechanical systems, providing a smoother and quieter
operation.
 Increased load capacity: In some cases, lubricants can increase the load-carrying capacity of mechanical systems, allowing for
higher performance and longer lifespans.
 Overall, lubrication and tribology are critical components of mechanical design and maintenance. Proper lubrication can lead
to improved efficiency, reliability, and reduced maintenance costs, making it essential for many industries and applications.
INTRODUCTION

8. Properties of lubricants
 Oxidation stability: Lubricants can break down over time due to oxidation, which can lead to reduced lubrication
effectiveness and increased wear. Oxidation stability is a measure of a lubricant's ability to resist oxidation and maintain its
properties over time.
 Additives: Lubricants often contain additives that can improve their performance or provide additional properties. For
example, anti-wear additives can reduce wear and extend the lifespan of machinery, while anti-foaming additives can reduce
the formation of bubbles in the lubricant.
 Chemical composition: The chemical composition of a lubricant can affect its properties and performance. For example,
synthetic lubricants can offer better performance in high-temperature and high-pressure applications due to their superior
chemical stability and resistance to thermal breakdown
LUBRICANTS

9. Types of Lubricants
 Different types of lubrication systems have been designed and developed over the years based on the specific requirements
of the instrument and the different industrial sectors. We are talking about the most popular and beneficial lubricant
systems used by different plants in different industrial sectors.
 Oil Lubrication System
 The oil lubrication system is also known as the loss lubrication system. In this system, oil or liquid grease produces a thin oil
film that protects the parts. It is renewed at regular intervals by an automatic lubrication system with an electric oil pump.
The main systems used in oil lubrication are single-line systems and 33V systems.
 Splash Lubrication System
 In these types of lubrication systems, the lubricating oil accumulates in an oil sump. Most small four-stroke petrol engines
use splash lubrication. On horizontal crankshaft engines, a dipper on the bottom of the connecting rod scoops up oil from the
oil sump for the bearings. When the engine runs, the dipper dips in the oil once in every crankshaft revolution and causes the
oil to splash on the cylinder walls.
 Recirculating Oil System
 The purpose of oil recirculation is to supply lubrication and provide cooling to bearings and gears. An electric pump ensures
that an appropriate lubricant pressure is available in the mainline, where the oil flow is also measured and regulated. etc.
LUBRICANTS

10. Properties of lubricants
 Lubricants can be categorized into various types such as liquid, solid, and semi-solid, and they exhibit different
physical and chemical properties. Here are some of the key properties of lubricants:
 Viscosity: Viscosity is a measure of a fluid's resistance to flow and is an important property of lubricants. A
higher viscosity means that the lubricant is thicker and flows more slowly, while a lower viscosity means that
the lubricant is thinner and flows more quickly. The viscosity of a lubricant is typically measured in centistokes
(cSt) or Saybolt Universal Seconds (SUS).
 Flash point: The flash point is the temperature at which a lubricant will give off enough vapor to ignite in the
presence of an ignition source. It is an important safety property for lubricants that are used in high-
temperature applications, such as engine oils. A higher flash point means that the lubricant is less likely to
catch fire
 Pour point: The pour point is the lowest temperature at which a lubricant will flow. It is an important property
for lubricants that are used in cold environments, as a lubricant with a high pour point may become too viscous
and not flow properly. A lower pour point means that the lubricant will remain fluid at lower temperatures.
LUBRICANTS

11. Surface characterization
 Surface characterization is an important aspect of tribology and involves the measurement and analysis of various properties of a
material's surface. Here are some of the key surface properties that are commonly characterized:
1. Roughness: Roughness is a measure of the irregularity of a surface, which can affect its tribological properties. Roughness is
typically measured using techniques such as profilometry, which involves scanning the surface with a stylus and measuring the
height variations. Roughness can impact properties such as friction, wear, and adhesion.
2. Hardness: Hardness is a measure of a material's resistance to indentation or scratching. It is an important property for materials
that are subject to wear, as harder materials are generally more wear-resistant. Hardness is typically measured using techniques
such as indentation testing, which involves pressing a hard object (such as a diamond tip) into the material and measuring the
depth of the indentation.
3. Surface energy: Surface energy is a measure of the energy required to create a new surface on a material. It is an important
property for materials that are subject to adhesion, as higher surface energy materials tend to have stronger adhesive properties.
Surface energy can be measured using techniques such as contact angle measurement, which involves measuring the angle
between a droplet of liquid and the surface.
 Surface topography: Surface topography refers to the 3D structure of a material's surface, including features such as bumps,
valleys, and grooves. Surface topography can affect properties such as friction, wear, and adhesion, and can be measured using
techniques such as atomic force microscopy (AFM) or scanning electron microscopy (SEM).
TRIBIOLOGY

12. Wear mechanisms
 Abrasive wear: Abrasive wear occurs when hard particles, such as dirt or debris, come into contact with a material's surface
and cause mechanical damage. This type of wear is commonly seen in applications where materials are subject to abrasive
environments, such as mining equipment or conveyor belts. The image below shows an example of abrasive wear on a steel
surface.
 Adhesive wear: Adhesive wear occurs when two surfaces come into contact and stick together, causing material to transfer
from one surface to the other. This type of wear is common in applications where materials are subject to high contact
pressures, such as bearings or gears. The image below shows an example of adhesive wear on a copper surface.
 Fatigue wear: Fatigue wear occurs when materials are subjected to repeated cyclic loading, which can cause cracks to form
and propagate over time. This type of wear is commonly seen in applications where materials are subject to high stress or
vibration, such as aircraft components or automotive parts. The image below shows an example of fatigue wear on an
aluminum alloy surface.
 Corrosive wear: Corrosive wear occurs when materials are subject to chemical attack, such as from acidic or alkaline
environments. This type of wear is commonly seen in applications where materials are exposed to harsh chemicals or
environments, such as pipelines or chemical processing equipment. The image below shows an example of corrosive wear on a
steel surface.
TRIBIOLOGY

13. Operating conditions
 Temperature:
 Temperature can affect lubrication and tribology in several ways. High temperatures can cause lubricants to break down or
evaporate, reducing their effectiveness in reducing friction and wear. Additionally, high temperatures can cause mechanical
components to expand, increasing the risk of surface-to-surface contact and wear. On the other hand, low temperatures can
cause lubricants to thicken, reducing their ability to flow and provide adequate lubrication. Therefore, it's important to
choose lubricants that can perform well under the operating temperature conditions of the system.
 Pressure:
 Pressure can also impact lubrication and tribology. High pressure can cause the lubricant film to break down, leading to
increased surface-to-surface contact and wear. Additionally, high pressure can cause metal surfaces to deform, leading to
increased friction and wear. It's important to choose lubricants that can withstand the pressure conditions of the system, as
well as ensuring that the system components are designed to handle the pressure requirements.
 Speed: The speed at which mechanical components move can also impact lubrication and tribology. High speeds can cause
increased friction and wear due to the increased contact between surfaces. Additionally, high speeds can cause lubricant film
thickness to decrease, reducing its effectiveness in reducing friction and wear. It's important to choose lubricants that can
withstand the speed conditions of the system and ensure that the components are designed to handle the speed requirements.
FACTORS AFFECTING LUBRICATION

14. Material properties
 Surface roughness: As mentioned earlier, surface roughness can impact tribological properties such as friction, wear,
and adhesion. Materials with smoother surfaces tend to have lower friction and wear rates, as they provide less surface
area for contact and adhesion with other materials.
• Hardness: Harder materials tend to be more wear-resistant, as they are less susceptible to indentation and scratching.
However, harder materials may also be more brittle and prone to cracking under certain loading conditions.
• Chemical composition: The chemical composition of a material can impact its tribological properties, particularly in
corrosive or reactive environments. Certain materials may be more resistant to corrosion or chemical attack, while
others may react more readily with specific chemicals or environments.
FACTORS AFFECTING LUBRICATION

15. Automotive industry
 The automotive industry is one of the primary areas where lubricants and tribology are applied to improve performance and
reliability. Here are some specific applications of lubricants and tribology in the automotive industry:
1. Engine lubrication: Lubricants are used to reduce friction and wear in the engine, which helps to increase efficiency and extend
the life of the engine. Engine oils are specifically formulated to provide the necessary lubrication and protection for the engine
components, including the pistons, bearings, and camshaft.
2. Transmission lubrication: Transmission fluids are used to lubricate and protect the transmission components, including the gears
and bearings. The fluid also helps to cool the transmission, which can prevent overheating and damage to the components.
3. Suspension and steering systems: Lubricants are used to reduce friction and wear in the suspension and steering systems, which
can improve handling and ride comfort.
4. Brake systems: Tribological principles are used in the design of brake systems to minimize wear and ensure consistent and
reliable braking performance.
 Overall, the use of lubricants and tribology in the automotive industry helps to improve performance, reliability, and safety, while
reducing energy losses and maintenance costs.
APPLICATIONS OF
LUBRICANTS AND TRIBOLOGY

16. Manufacturing industry
 The manufacturing industry relies heavily on lubricants and tribology to improve the efficiency and productivity of metalworking
and machining processes. Here are some specific applications of lubricants and tribology in the manufacturing industry:
1. Metalworking: Lubricants are used to reduce friction and wear in metalworking processes, such as cutting, stamping, and forming.
By reducing friction and wear, lubricants help to extend the life of the tools and improve surface finish quality.
2. Machining: Lubricants are used in machining processes such as drilling, milling, and grinding to reduce friction and heat
generation, which can cause tool wear and damage. The use of lubricants in these processes can improve the tool life and
productivity.
3. Surface finishing: Tribological principles are applied in surface finishing processes, such as polishing and lapping, to reduce
friction and improve surface finish quality.
4. Bearings and gears: Lubricants are used in the design and operation of bearings and gears to reduce friction and wear, which can
extend the life of these components and improve their performance.
 Overall, the use of lubricants and tribology in the manufacturing industry helps to improve the efficiency and productivity of
metalworking and machining processes, leading to cost savings and higher quality products.
APPLICATIONS OF
LUBRICANTS AND TRIBOLOGY

17. Aerospace industry
 The aerospace industry relies on lubrication and tribology to ensure safe and reliable operation of aircraft components. Here
are some specific applications of lubricants and tribology in the aerospace industry:
 Landing gear lubrication: Landing gear systems require lubrication to ensure smooth and safe operation during takeoff and
landing. Lubricants are used to reduce friction and wear in the landing gear components, such as the wheels, brakes, and
struts.
 Turbine lubrication: The turbines in aircraft engines require lubrication to reduce friction and wear, which can cause damage
to the turbine blades and reduce engine efficiency. Turbine lubricants are specially formulated to provide the necessary
lubrication and protection for these critical components.
 Bearings and gears: Bearings and gears are critical components in many aircraft systems, including engines, landing gear, and
control systems. Lubricants are used to reduce friction and wear in these components, which can extend their life and
improve their performance.
 Hydraulic systems: Hydraulic systems are used in many aircraft systems, including landing gear, brakes, and flight control
systems. Lubricants are used in these systems to reduce friction and wear, which can improve reliability and performance.
 Overall, the use of lubricants and tribology in the aerospace industry helps to ensure safe and reliable operation of aircraft
components, which is critical for the safety of passengers and crew.
APPLICATIONS OF
LUBRICANTS AND TRIBOLOGY

18. MEDICAL INDUSTRY
 Lubrication and tribology play an important role in the development and operation of medical devices, such as prosthetic
joints. Here are some specific applications of lubricants and tribology in the medical industry:
 Prosthetic joint lubrication: Lubrication is essential for the proper function and longevity of prosthetic joints, such as hip and
knee replacements. Lubricants are used to reduce friction and wear in these joints, which can improve mobility and reduce
the risk of implant failure.
 Medical devices: Many medical devices, such as catheters and surgical tools, require lubrication to reduce friction and
improve their function. Lubricants are used to reduce the risk of tissue damage and infection during medical procedures.
 Biocompatibility: Lubricants used in the medical industry must be biocompatible, meaning they are safe for use in the human
body and do not cause adverse reactions. Biocompatible lubricants are specially formulated to meet the unique requirements
of medical applications.
 Overall, the use of lubricants and tribology in the medical industry helps to improve the function and longevity of medical
devices, leading to improved patient outcomes and quality of life
APPLICATIONS OF
LUBRICANTS AND TRIBOLOGY

19. Renewable energy
 Lubrication and tribology are critical to the efficient and reliable operation of renewable energy
systems, such as wind turbines and solar panels. Here are some specific applications of lubricants and
tribology in the renewable energy industry:
 Wind turbine lubrication: Wind turbines require lubrication to reduce friction and wear in their
mechanical components, such as bearings, gears, and hydraulic systems. Proper lubrication can help
extend the life of these components and improve the efficiency and reliability of the turbine.
 Solar panel tracking: Solar panels often use tracking systems to follow the sun and maximize energy
production. These tracking systems require lubrication to reduce friction and wear in their moving
components, such as bearings and gears. Proper lubrication can help improve the efficiency and
reliability of the solar panel system.
 Wave energy converters: Wave energy converters use mechanical systems to convert the motion of waves
into electrical energy. These systems require lubrication to reduce friction and wear in their mechanical
components, such as bearings and hydraulic systems. Proper lubrication can help extend the life of these
components and improve the efficiency and reliability of the system.
 Overall, the use of lubricants and tribology in the renewable energy industry helps to improve the
efficiency and reliability of renewable energy systems, leading to increased energy production and
reduced maintenance costs.
APPLICATIONS OF
LUBRICANTS AND TRIBOLOGY

20. Summary of lubricants and tribology principles
 Lubrication and tribology principles are critical in reducing friction and wear between surfaces in mechanical systems, resulting in
improved efficiency, reliability, and longevity. The key principles of lubrication and tribology include:
 Viscosity: The viscosity of a lubricant is critical to its performance. Viscosity refers to the thickness or resistance to flow of a
lubricant, and influences its ability to create a film between two surfaces and reduce friction.
 Boundary lubrication: Boundary lubrication occurs when a thin layer of lubricant molecules adheres to the surface of two moving
components, creating a barrier between them and reducing friction and wear.
 Elastohydrodynamic lubrication (EHL): EHL occurs when the pressure between two moving surfaces is high enough to cause
the lubricant to deform, creating a thin film of lubricant between the surfaces.
 Wear: Wear is the gradual loss of material due to mechanical forces such as friction, abrasion, and erosion. Lubricants can help
reduce wear by providing a barrier between two surfaces and reducing the mechanical forces acting on them. Additives: Additives
are chemicals added to lubricants to improve their performance in specific applications. Common additives include anti-wear
agents, corrosion inhibitors, and viscosity improvers.
CONCLUSION

21. Importance of lubricants and tribology in modern society
 Lubricants and tribology play a crucial role in modern society. Virtually all machines and mechanical systems rely on
lubrication to operate effectively and efficiently. Here are some key areas where lubricants and tribology are essential:
 Transportation: The automotive industry relies heavily on lubricants to maintain engine performance and reduce wear on key
components. Lubricants are also important in aviation and aerospace, where they help to reduce friction and wear between
moving parts and minimize energy consumption.
 Manufacturing and Industry: Lubrication is also important in industrial machinery and equipment, where it helps to reduce
downtime, increase productivity, and improve product quality. For example, lubricants are used in metal forming, casting, and
machining operations to reduce friction and wear on cutting tools.
 Energy production: Lubricants are essential in energy production, including oil and gas extraction, power generation, and
renewable energy sources such as wind turbines. In these applications, lubricants help to reduce friction and wear in critical
components, improve efficiency, and extend the life of equipment.
 Healthcare and Biotechnology: Lubrication is also important in healthcare and biotechnology, where it is used in medical
devices, pharmaceutical manufacturing, and bioprocessing. For example, lubricants are used in syringes, catheters, and other
medical devices to reduce friction and ensure smooth operation.
 Overall, lubricants and tribology are essential to modern society, enabling efficient and reliable operation of machinery and
equipment across a wide range of industries. The continued development of lubricants and tribology research will be critical
for advancing technology and improving sustainability in the future.
CONCLUSION

22. FUTURE DIRECTIONS IN LUBRICANT AND TRIBOLOGY RESEARCH
 The field of lubrication and tribology is constantly evolving, and there are many exciting research areas and
emerging technologies. Here are some future directions in lubricant and tribology research:
 Development of advanced lubricants: One of the areas of interest is the development of advanced lubricants
with improved performance and longevity. This includes the use of nanolubricants, ionic liquids, and graphene-
based lubricants.
 Eco-friendly lubricants: Another area of research is the development of eco-friendly lubricants that are
biodegradable and non-toxic, reducing the environmental impact of lubrication.
 Smart lubrication systems: The use of smart lubrication systems that can detect changes in operating conditions
and adjust lubrication properties in real-time is also an area of interest. This includes the development of
sensors and algorithms that can monitor and optimize lubrication performance.
CONCLUSION

23. FUTURE DIRECTIONS IN LUBRICANT AND TRIBOLOGY RESEARCH
 Tribological coatings: Advances in additive manufacturing and materials science are opening up new possibilities
for designing components with optimized tribological properties. This includes the development of tribological
coatings that can reduce friction and wear on surfaces.
 Tribological simulation: The use of computer simulation and modeling is becoming increasingly important in
tribology research. Tribological simulation can help to understand the fundamental mechanisms of friction and
wear and optimize lubrication performance.
 Biomimetic lubricants: Researchers are exploring the use of biomimetic lubricants that mimic the lubrication
properties found in biological systems. This includes the development of lubricants based on natural materials
such as proteins, lipids, and polysaccharides.
CONCLUSION

24. OPPORTUNITIES FOR INNOVATION AND PROGRESS IN THE FIELD.
 The field of lubrication and tribology offers numerous opportunities for innovation and progress. Here are some areas where
advancements are possible:
1. New materials: Advances in materials science are leading to the development of new lubricants and tribological coatings with
improved performance and durability. For example, researchers are exploring the use of graphene, carbon nanotubes, and other
advanced materials to create high-performance lubricants with unique properties.
2. Smart systems: The use of smart lubrication systems that can adjust lubrication properties in real-time based on changing
operating conditions is an area of active research. These systems can improve efficiency, reduce wear, and extend equipment
life.
3. Eco-friendly lubricants: There is growing interest in the development of eco-friendly lubricants that are biodegradable, non-
toxic, and sustainable. This includes the use of renewable resources such as vegetable oils, as well as the development of
biodegradable additives and base oils.
4. Tribological simulation: Advances in computer simulation and modeling are enabling researchers to better understand the
fundamental mechanisms of friction and wear. This includes the development of sophisticated models that can predict tribological
behavior at the atomic and molecular scale.
5. Biomimetic lubricants: The use of biomimetic lubricants that mimic the lubrication properties found in biological systems is an
emerging area of research. For example, researchers are exploring the use of proteins, lipids, and other natural materials as the
basis for high-performance lubricant
CONCLUSION

25. THANK
YOU