Short Answer:

Lubrication systems are used to supply lubricants to different machine parts for smooth operation. These systems ensure that the lubricant reaches the required areas in the correct amount and at the right time. The main purpose is to reduce friction, wear, and overheating in moving parts.

There are several types of lubrication systems used in mechanical engineering such as manual lubrication system, splash lubrication system, pressure feed lubrication system, and mist lubrication system. Each system works differently depending on the type of machinery and its operating conditions.

Detailed Explanation :

Types of Lubrication Systems

Lubrication systems are essential in mechanical systems to ensure that moving parts receive a continuous and adequate supply of lubricants. The main purpose of a lubrication system is to reduce friction between surfaces, prevent wear, carry away heat, and protect machine components from rust and corrosion. Without a proper lubrication system, machines may suffer from rapid wear, overheating, and breakdowns.

Lubrication systems are designed based on the type, speed, load, and working environment of machines. Different types of lubrication systems are used in engines, bearings, gears, turbines, and industrial machinery. Each type of lubrication system has its own working principle and method of supplying lubricant. The selection of a lubrication system depends on the design and requirement of the machine.

1. Manual Lubrication System

In a manual lubrication system, lubricants such as oil or grease are applied to machine parts manually with the help of oil cans, grease guns, or brushes. This method is simple and inexpensive, but it depends on human effort. It is mainly used in small machines or equipment that do not require continuous lubrication.

• Advantages: Easy to use, low cost, and suitable for small setups.
• Disadvantages: Irregular supply, more labor required, and not suitable for high-speed machinery.

2. Splash Lubrication System

The splash lubrication system is one of the simplest and most commonly used systems in small engines, such as in motorcycles and small generators. In this system, a scoop or dipper attached to the crankshaft splashes the lubricant onto the moving parts as it rotates. The splashed oil reaches the bearings, cylinder walls, and other components that need lubrication.

• Advantages: Simple design, no pump required, and low maintenance.
• Disadvantages: Limited control over oil supply, not suitable for high-speed or large engines.

3. Pressure Feed Lubrication System

In the pressure feed lubrication system, a pump is used to supply lubricant under pressure to the engine parts. The oil is drawn from a sump and delivered through drilled passages to bearings, pistons, and other components. This system ensures uniform and continuous lubrication, making it suitable for large and high-speed engines such as automobile engines.

• Advantages: Continuous lubrication, better control, and efficient operation.
• Disadvantages: Higher cost, complex system, and requires maintenance of the pump and filters.

4. Wet Sump Lubrication System

The wet sump system is a type of pressure feed system used in internal combustion engines. In this method, the oil is stored in a sump (bottom part of the engine crankcase). The oil pump draws the lubricant from the sump and circulates it to various engine parts under pressure. After lubrication, the oil returns to the sump by gravity.

• Advantages: Simple arrangement, good for light to medium engines, and easy oil circulation.
• Disadvantages: Not suitable for racing or inclined engines due to oil flow variation.

5. Dry Sump Lubrication System

In a dry sump system, the oil is stored in a separate external tank instead of the engine sump. A scavenge pump collects oil from the engine and sends it back to the tank. A pressure pump then supplies the oil to the required parts. This system is used in racing cars, aircraft, and heavy-duty engines where continuous lubrication is required even during high-speed or inclined operations.

• Advantages: Better cooling, continuous oil supply, and suitable for high-performance engines.
• Disadvantages: Expensive, complex design, and requires more space.

6. Mist Lubrication System

In the mist lubrication system, the lubricant is mixed with air in a fine mist form and supplied to the moving parts. This method is commonly used in two-stroke engines and high-speed machines. The mist enters the cylinder with the air-fuel mixture and lubricates the piston and crankshaft.

• Advantages: Simple system, lightweight, and no separate oil pump needed.
• Disadvantages: Not suitable for large engines and may cause incomplete combustion due to oil mixture.

7. Oil Bath Lubrication System

In this system, machine parts like gears or chains are partially dipped in an oil bath. When the parts move, they carry a film of oil and distribute it to other areas. This system is used in gearboxes, chain drives, and enclosed systems.

• Advantages: Easy to maintain and provides consistent lubrication.
• Disadvantages: Oil contamination and overheating can occur if not maintained properly.

Conclusion:

Lubrication systems are crucial for the smooth and efficient working of machines. Different systems like manual, splash, pressure feed, wet sump, dry sump, and mist lubrication systems are used depending on machine type and requirement. Each system has its own advantages and limitations, but the main goal remains the same — to reduce friction, wear, and overheating while ensuring reliable operation. Proper lubrication not only increases the efficiency of machines but also extends their service life.