Air is compressed into a tank using a device called an air compressor. The most common type uses a piston inside a cylinder to reduce the volume of air, thus increasing its pressure and forcing it into a storage tank.
Here's a more detailed breakdown of the process:
The Air Compressor's Role
An air compressor's primary function is to take atmospheric air and compress it into a smaller volume, thereby increasing its pressure. This high-pressure air can then be used to power various tools and equipment.
The Compression Process
The process typically involves the following steps:
- Intake: The piston moves downward inside the cylinder, creating a vacuum. This causes a one-way inlet valve to open, allowing atmospheric air to be drawn into the cylinder.
- Compression: The crankshaft's rod then raises the piston inside the cylinder, reducing the volume of air inside. This decrease in volume causes a significant increase in air pressure. The inlet valve closes to prevent air from escaping.
- Discharge: As the piston reaches the top of its stroke, the compressed air reaches its maximum pressure. This pressure forces open a one-way outlet valve.
- Tank Storage: The compressed air is then pushed through the outlet valve and into the storage tank. This process repeats continuously until the tank reaches its pre-set maximum pressure. At that point, a pressure switch shuts off the compressor motor.
- Pressure Regulation: A pressure regulator is typically used to control the output pressure delivered from the tank to the connected tool or application. This ensures consistent and safe operation.
Key Components
- Cylinder: The chamber where the piston moves to compress the air.
- Piston: The component that moves up and down within the cylinder to compress the air.
- Crankshaft: Converts rotational motion from the motor into the linear motion of the piston.
- Inlet Valve: Allows air to enter the cylinder during the intake stroke.
- Outlet Valve: Allows compressed air to exit the cylinder and enter the tank.
- Storage Tank: Holds the compressed air until it is needed.
- Motor (Electric or Gas): Provides the power to drive the crankshaft.
Types of Air Compressors
While the piston-cylinder method is the most common, other types of air compressors exist, including:
- Rotary Screw Compressors: Use rotating screws to compress air. These are generally used for larger industrial applications requiring continuous air supply.
- Centrifugal Compressors: Use a rotating impeller to accelerate air and then convert that kinetic energy into pressure. Often used in large-scale industrial applications like gas pipelines.
Example
Imagine using an air compressor to inflate a car tire. The compressor's piston compresses air, increasing its pressure. This high-pressure air is then forced into the tire, increasing the tire's internal pressure until it reaches the desired level.
