compressed air systems

A compressed air system is much more complex than just a simple air compressor and some hose or piping to get the air to the place where it is needed.

Compressed Air is used in both commercial and residential applications. Most people are unaware of how much their daily life depends on compressed air. 

From the air in the tires of your vehicles to the manufacture of products we use daily, compressed air as played a role in making it all possible. 

Understanding what, how, and why of compressed air gives us an appreciation of the importance of compressed air systems to our way of life.

What is a Compressed Air System?

A compressed air system is much more complex than just a simple air compressor and some hose or piping to get the air to the place where it is needed.  Different applications for the compressed air have different requirements such as 

  • The volume of compressed air required
  • The pressure of the supplied compressed air
  • The quality of the compressed air
  • The temperature of the compressed



What Are The Components of Compressed Air Systems?

  • Air Receivers
  • Air Dryers
  • Filters
  • Regulators
  • Pipes

Compressed air production systemThe exact parts of a compressed air system will vary depending on the demands and needs of the end-user. 

These demands can be as simple as a small single-stage compressor in your garage used to air up tires or inflate tires or for automotive work.

At the other end of the scale are large industrial systems that deliver compressed air to hundreds of workstations or drive the mechanics of the industrial processes performed.  

In general, the components that make up a compressed air system include:

The Air Compressor 

The Air Compressor is the heart of the system.  This analogy holds very accurate since at the core of an air compressor is a pump of some design that does all the work.  The parts of the air compressor pump also usually include:

  • A prefilter assembly – Most compressors include a prefilter assembly that prevents air-borne particulate contaminants from getting into the compressor itself.  Dust and other particles can have a devastating effect on an air compressor.  Even small home-style compressors have some sort of prefilter arrangement to keep as much debris from entering the compressor as possible.
  • The air compressor – The heart of an air compressor system is the compressor or pump.  An air compressor is a machine that uses a power source such as an electric motor or diesel engine to turn the compressor pump.  Compressor pumps come in several different types including
  • An aftercooler – Many large air compressor systems have an aftercooler.  The aftercooler reduces the temperature of the lubricants used in the air compressor and the discharge compressed air.   

Post Compressor Systems – Air Receivers

Air ReceiversOne of two things must happen after the newly compressed air leaves the air compressor pump.  In many applications, air storage in air receivers or tanks is part of the design. 

Compressed air kept in tanks at operating pressure allows a reserver capacity in the system to prevent the air compressor from operating past its duty cycle and to absorb sudden spikes in compressed air demand.  

Systems with the air compressor pump integrated into the air receiver or tank are common in many applications. Even in some large industrial situations, a compressor pump, dryer, and the post-compressor filtration systems integration is the norm. 

These package style designs make installation and maintenance of these systems more economical and often quicker.

Post-Compressor Filters and Air Dryers 

Some applications require compressed air that is free of moisture or other contaminants that can come from the process of compressing and storing the air. 

Air dryers of different types, as well as post-filtrations systems, are used to provide much higher quality air for applications such as food processing or medical and dental needs.

Refrigerated Air Dryers

Refrigerated air dryers use the same basic principles as your home refrigerator to cool and remove the moisture from the compressed air in your system. The refrigerated dryer cools the air in an air-to-refrigerant exchange system.

This cooling process causes most of the remaining water vapor in the compressed air to condense where it drains away, leaving cool, dry compressed air to be sent further down the line in your compressed air system.

Desiccant Air Dryers  

Another type of air dryer often used in commercial or industrial compressed air systems is the desiccant air dryer. These systems use a desiccant in a tower arrangement.

The hot compressed air passes through the desiccant material where the water vapor is adsorbed by the desiccant, causing the temperature of the compressed air to drop. Periodically, the desiccant towers must reverse the cycle and purge the desiccant material of the trapped water.

Filtration

Some food processing and medical applications require even higher qualities of compressed air.  In many of these situations, an additional level of filtration is added to the system to trap any errant particulates or contaminants that may still remain in the compressed air.

Post-compressor filtration may be of a cartridge type or may involve a more complicated filtration system tailored to the specialized needs of the application.





Compressed Air Regulators

Compressed Air RegulatorsEvery compressed air system has one or more compressed air regulators installed after the compressor to manage the pressure delivery through the piping to the end use of the compressed air. 

Regulators are pressure reducers that further control the variations in the pressure of the compressed air allowing the delivery of a stable and steady flow of compressed air at controlled air pressures

A complicated compressed air system may have one compressed air regulator at the outflow of the compressor to manage the airflow and pressure during the filtration and drying stages of the system. 

Air regulator installations at the use of the compressed air is a common practice since different machines and tools may require different flow rates and different pressures.  

Piping

Larger industrial applications and some medical applications require the compressed air system to serve locations separated from the compressor and other equipment. 

compressed PipingOne good example of this is the dentist’s office, where high quality compressed air is delivered to the dentist chair to operate the tools used in dental procedures.

In a sizeable industrial setting, compressed air requires delivery to machinery and work stations, often located hundreds of meters from the site of the air compressor.

These systems demand well-engineered and properly sized delivery systems.  These systems often are a combination of different types of piping.

  • Metal piping – In practice, engineers specify metal piping for long pipe runs or where extremely high pressures exist in the system.   Depending on the use and quality of the compressed air, the piping material may include stainless steel or aluminum.
  • Polyethylene Pipe – Some parts of a compressed air system may use polyethylene or PE pipe and fittings to make the final leap from the metal piping to the end-user.  These end uses include pneumatically-driven machines or robots or workstations.



Monitoring and Instrumentation

Where the quality of the compressed air delivery is critical, such as food processing or medical uses, the system must support the real-time monitoring of the compressed air in the system.

These monitors can be placed anywhere in the system.  Typically, they include reporting and alert systems that alarm if a problem occurs in the compressed air system.

Breathing Air Systems

compressed Breathing Air SystemsCompressed air systems designed to deliver breathing quality air are in an entire class by themselves.  Various state and federal regulations regulate any system delivering breathing air. 

These systems must conform to a host of quality control standards, testing, and inspection routines. 

Breathing air systems are generally self-contained and separate from any other compressed air systems that may be in use in the facility.

It is easy to see that compressed air systems can be as uncomplicated as a small pancake compressor for home use with an integral tank to large systems that have hundreds of feet of piping and large air receivers to operate machinery and industrial tools.  

Leask Detection and Management

compressed air systems work fullIn systems that can grow to be complicated, and that includes a vast number of connections, joints, and possibly fail points, leakage in a compressed air system is a problem.

Not only is it wasteful, but leakage can be and financial issue.  Air that leaks from a compressed air system is money spent and wasted.

Leak detection systems are now standard on most industrial compressed air systems.

Where is Compressed Air Used?

compressed air systems workIf you look around your home or office, almost everything that you see has, in some form or fashion, required compressed air to get to you.

The delivery trucks roll on tires the depend on compressed air.  There is a long list of industries where compressed air is essential.

  • Production line tools
  • Automated robotic assembly systems
  • Facilities maintenance
  • Food preparation and packaging
  • Medical and dental applications
  • Power generation
  • Painting
  • Pharmaceutical production
  • Woodworking and construction

Also, many individuals keep small air compressors around their homes for routine maintenance jobs on their vehicles and other items.  Compressed air is ubiquitous and is essential in almost every industry that touches our lives.

The Cost of Compressed Air

Several determining factors affect the cost of a compressed air system.  In general, these factors include:

  • The quality of the air needed
  • The volume of air needed
  • The pressure of the compressed air
  • The size of the application

The actual cost of a compressed air system is hard to estimate without a lot of information about these factors.  However, we can look at some of the general uses of compressed air and the cost of systems to serve those applications.

Better Understanding Leads To Better Decisions

The more you understand about compressed air systems, the better the decisions you can make about your needs and which compressed air system can best fit.

I hope that this article has given your insight and information that will make your compressed air system decision easier.