What is a reciprocating air compressor?

Commonly called a piston compressor or recip (short for reciprocating) compressor, these models use a piston in a chamber (cylinder) to decrease volume and increase pressure. The reciprocating motion comes from the piston moving back and worth.

Basic operation principles of a reciprocating air compressor

In these positive displacement compressors, air is mechanically reduced causing a corresponding increase in pressure. Applying the principle of reciprocation, which means to move something back and forth, the piston moves back and forth in the chamber which causes a corresponding increase in pressure.As the rotor spins the piston is moved up and down. When the piston goes up air is drawn into the cylinder. As the piston recoils the air is compressed and forced out at a higher pressure. The compressed air is then used immediately by a pneumatic machine or stored in a compressed air tank.

Types of reciprocating compressors

Single acting reciprocating compressors are the most common and inexpensive compared to other technologies. They are good for compressors that will be running in intermittent duty cycles. These compressors are relatively simple and easy to maintain with less moving parts.

• One compression cycle for every turn
• Inlet or suction valve and discharge valve (both one way and spring loaded)
• Piston moves downward, and then air is sucked in
• Piston moves upward, it opens a discharge valve and traps air inside. This reduces the volume and increases the pressure. When enough force is applied, the air is released at a high pressure.

Double acting reciprocating compressors are less common due to their large size, high noise and vibration levels.

• Two compression cycles for every turn
• Inlet and discharge valves on both sides of cylinder
• Operation is similar to single acting, in which the piston moves up and down to increase the pressure
• Efficient, but less common due to large size and higher HP which results in higher noise levels and vibration
• In recent years these models have been replaced with rotary screw technology

Diaphragm reciprocating compressors are not commonly used for air compression, and are more of a niche offering.

• Similar to single acting, one compression cycle per turn
• No cylinder, piston moves a diaphragm that contracts and expands
• Not frequently used for air, typically used to compress water

Single and Multistage Reciprocating Compressors

Single acting reciprocating compressors are available in single and multistage. The maxpressure of a single stage is about 125 psi. Reaching a higher pressure requires a multistagereciprocating compressor. Multistage reciprocating compressors use cylinders of different sizes – cylinder 1 pumps theair up to one pressure, then moves to a smaller cylinder to achieve a higher pressure. Dueto the increased and higher pressure, these models may require an air cooler or heat exchanger.

Where are reciprocating compressors used?

• Designed for intermittent duty applications in harsh environments
• Best suited for applications where the compressor is turned on and off frequently
• In a wide variety of applications including auto body shops, tire shops, woodworking facilities, construction sites, amusement parks, and industrial facilities.

Benefits of Reciprocating Air Compressors

• Low installation costs
• Save energy in no-load conditions and operate efficiently at partial load
• Less moving parts when compared to other types of compressors, resulting in lower maintenance requirements

Learn More About Our Reciprocating Compressors

Reciprocating compressors are known for their durability and are often considered the “work-horse” of air compressors. They offer a small footprint, low installation cost and low maintenance costs. Learn more about our reciprocating compressors, view our comprehensive product portfolio.

The Basic Working Principle

Reciprocating air compressors work on the principle of reciprocation, which means to move something back and forth. They are positive displacement type compressors meaning when the air is mechanically reduced, a corresponding increase in pressure occurs.

Reciprocating compressors use pistons to compress air. In these types of compressors, a rotor spins, causing a piston to move up and down. When the piston goes down, air is pulled into a chamber.

As the piston moves back up, the air is compressed and forced out. The compressed air is then used immediately by a pneumatic machine or stored in a compressed air tank.

Where are these compressors best suited?

Reciprocating compressors are engineered to work efficiently in a wide variety of applications. They are used in auto body, carwash, tire shops, woodworking facilities, construction sites, amusement parks, and industrial facilities. You can depend on a reciprocating compressor when operating in less than ideal conditions.

Featuring low installation costs, reciprocating compressors are designed for intermittent duty applications in harsh environments. They are best suited for applications where the compressor is turned on and off frequently.

Reciprocating compressors save energy in no-load conditions and operate efficiently at partial load. This leads to higher overall efficiency for the compressor, resulting in lower maintenance costs. In addition, a reciprocating compressor has lower maintenance costs due to less moving parts when compared to other air compressor technologies.