Study of lubrication system: need, types, functional components

Introduction

The lubrication system plays a crucial role in the proper functioning and longevity of machinery. It is responsible for reducing friction and wear between moving parts, ensuring smooth operation, and preventing damage. In this topic, we will explore the need for a lubrication system and discuss its types and functional components.

Importance of Lubrication System in Machinery

The lubrication system is essential for machinery because:

• It reduces friction between moving parts, preventing excessive wear and tear.
• It helps dissipate heat generated during operation, preventing overheating.
• It prevents corrosion and rust formation on metal surfaces.
• It helps maintain the overall efficiency and performance of the machinery.

Fundamentals of Lubrication System

Before diving into the types and components of the lubrication system, let's understand some fundamental concepts:

• Lubricant: A lubricant is a substance that reduces friction between moving surfaces. It can be a liquid, solid, or gas.
• Lubrication: Lubrication is the process of applying a lubricant to the surfaces in contact to reduce friction and wear.
• Lubrication System: A lubrication system is a mechanism that delivers the lubricant to the moving parts of machinery.

Study of Lubricants

To understand the lubrication system better, let's first explore the lubricants used:

Physical Properties of Lubricants

Lubricants possess certain physical properties that make them suitable for reducing friction and wear. These properties include:

• Viscosity: Viscosity is the measure of a lubricant's resistance to flow. It determines how well the lubricant can form a protective film between moving surfaces.
• Flash Point: The flash point is the lowest temperature at which a lubricant can vaporize and ignite when exposed to an open flame.
• Pour Point: The pour point is the lowest temperature at which a lubricant can flow under specific conditions.
• Oxidation Stability: Oxidation stability refers to a lubricant's ability to resist chemical reactions with oxygen, preventing degradation.

Additives Used in Lubricants and Their Applications

Lubricants often contain additives to enhance their performance and provide additional benefits. Some common additives and their applications include:

• Anti-wear additives: These additives form a protective layer on metal surfaces, reducing wear and extending the life of the machinery.
• Extreme pressure additives: These additives are used in high-pressure applications to prevent metal-to-metal contact and reduce friction.
• Viscosity modifiers: Viscosity modifiers help maintain the lubricant's viscosity under different temperature conditions, ensuring optimal performance.
• Detergents and dispersants: These additives help keep the lubricant clean by preventing the formation of deposits and sludge.

Types of Lubrication Systems

There are several types of lubrication systems used in machinery. Let's explore each type in detail:

Splash Lubrication System

The splash lubrication system is commonly used in small engines and some machinery. It works on the principle of oil splashing onto the moving parts. The components involved in a splash lubrication system are:

1. Crankcase: The crankcase holds the lubricating oil.
2. Dipper: The dipper is a scoop-like device that picks up oil from the crankcase and splashes it onto the moving parts.
3. Oil Sump: The oil sump collects the oil after it has been splashed onto the parts.

Advantages of splash lubrication system:

• Simple and cost-effective
• No external pump required

Disadvantages of splash lubrication system:

• Limited lubricant distribution
• Inadequate lubrication at high speeds or under heavy loads

Pressure Lubrication System

The pressure lubrication system is commonly used in most modern machinery, including engines and industrial equipment. It works on the principle of delivering oil under pressure to the moving parts. The components involved in a pressure lubrication system are:

1. Oil Pump: The oil pump is responsible for circulating the lubricating oil.
2. Oil Filter: The oil filter removes impurities from the oil.
3. Oil Cooler: The oil cooler helps dissipate heat from the oil.
4. Oil Pressure Relief Valve: The oil pressure relief valve regulates the oil pressure.

Advantages of pressure lubrication system:

• Efficient lubricant distribution
• Suitable for high-speed and heavy-load applications

Disadvantages of pressure lubrication system:

• More complex and expensive
• Requires regular maintenance

Mist Lubrication System

The mist lubrication system is commonly used in two-stroke engines and some industrial machinery. It works on the principle of mixing oil with compressed air to form a mist that is delivered to the moving parts. The components involved in a mist lubrication system are:

1. Oil Reservoir: The oil reservoir stores the lubricating oil.
2. Compressor: The compressor pressurizes the air.
3. Mixer: The mixer mixes the oil and compressed air to form a mist.
4. Distributor: The distributor delivers the mist to the moving parts.

Advantages of mist lubrication system:

• Effective lubrication of moving parts
• Reduced oil consumption

Disadvantages of mist lubrication system:

• Requires a compressor
• Limited to specific applications

Forced-Feed Lubrication System

The forced-feed lubrication system is commonly used in large machinery and some industrial equipment. It works on the principle of delivering oil under pressure to the moving parts through a network of pipes and nozzles. The components involved in a forced-feed lubrication system are:

1. Oil Pump: The oil pump circulates the lubricating oil.
2. Oil Cooler: The oil cooler helps dissipate heat from the oil.
3. Oil Filter: The oil filter removes impurities from the oil.
4. Pipes and Nozzles: The pipes and nozzles distribute the oil to the moving parts.

Advantages of forced-feed lubrication system:

• Precise and controlled lubricant delivery
• Suitable for large machinery

Disadvantages of forced-feed lubrication system:

• More complex and expensive
• Requires regular maintenance

Functional Components of Lubrication System

The lubrication system consists of various functional components that work together to ensure proper lubrication. Let's explore these components:

Oil Pump

The oil pump is responsible for circulating the lubricating oil throughout the system. It draws oil from the reservoir and delivers it to the moving parts. There are different types of oil pumps, including:

1. Gear Pump: The gear pump uses meshing gears to create suction and deliver oil.
2. Vane Pump: The vane pump uses rotating vanes to create suction and deliver oil.
3. Piston Pump: The piston pump uses reciprocating pistons to create suction and deliver oil.

The oil pump's working principle involves creating a pressure difference to draw oil into the pump and then delivering it under pressure to the lubrication points. The oil pump is a critical component of the lubrication system as it ensures proper oil circulation and lubrication.

Oil Filter

The oil filter is responsible for removing impurities and contaminants from the lubricating oil. It helps maintain the cleanliness of the oil and prevents damage to the moving parts. There are different types of oil filters, including:

1. Mechanical Filters: Mechanical filters use a mesh or screen to trap large particles.
2. Centrifugal Filters: Centrifugal filters use centrifugal force to separate contaminants from the oil.
3. Magnetic Filters: Magnetic filters use magnets to attract and remove metallic particles from the oil.

The oil filter's purpose is to ensure that only clean oil reaches the moving parts, reducing the risk of wear and damage.

Oil Cooler

The oil cooler is responsible for dissipating heat from the lubricating oil. It helps maintain the oil's temperature within the desired range, preventing overheating and thermal degradation. The oil cooler works by passing the oil through a series of tubes or fins, allowing heat to transfer to the surrounding air or coolant.

The oil cooler is particularly important in applications where the machinery operates at high temperatures or under heavy loads. It helps prolong the life of the lubricant and ensures optimal lubrication.

Oil Pressure Relief Valve

The oil pressure relief valve is responsible for regulating the oil pressure within the lubrication system. It prevents excessive pressure buildup, which can lead to oil leaks, component damage, or system failure. The oil pressure relief valve opens when the pressure exceeds a certain threshold, allowing excess oil to bypass and return to the reservoir.

The oil pressure relief valve is a safety feature that helps protect the lubrication system and the machinery from damage due to excessive pressure.

Summary

The lubrication system is essential for machinery as it reduces friction, dissipates heat, prevents corrosion, and maintains efficiency. It consists of different types of lubrication systems, including splash, pressure, mist, and forced-feed. Each system has its advantages and disadvantages, depending on the application. The functional components of the lubrication system, such as the oil pump, oil filter, oil cooler, and oil pressure relief valve, work together to ensure proper lubrication, cleanliness, temperature control, and pressure regulation. Understanding the lubrication system is crucial for maintaining machinery and ensuring optimal performance.

Analogy

Imagine a well-oiled machine as a well-functioning team. Each team member has a specific role and works together to achieve a common goal. The lubrication system is like the team manager who ensures that everyone has the necessary resources and support to perform their tasks effectively. The lubricant acts as the communication medium, allowing smooth interaction between team members. The different types of lubrication systems are like different management styles, each suited for specific situations. The functional components of the lubrication system are like the tools and equipment provided to the team members, enabling them to perform their tasks efficiently. Just as a well-managed team can achieve great results, a well-designed and maintained lubrication system ensures the smooth operation and longevity of machinery.