Do you know that your refrigerator, HVAC system and car use air compressors? When you have a flat tire or your AC stops cooling at the height of summer, your air compressor may be the go-to device to solve your problems.
While many industries use compressed air, you probably don’t know you use one every day. Neither do you know how one operates or the many applications of these versatile appliances.
From your bike tire’s pump, impact wrenches, leaf blowers, gas stations, to heavy industries, compressed air has multiple functions. Nowadays, you can power most tools in your workshop with compact air compressors from a variety of manufacturers.
In this article, we look at the air compressor, what it is, how it operates and what you can do with one. This promises to be a great read. Let’s begin!
What Is an Air Compressor?
An air compressor is a mechanical device that converts power from an electric motor or combustion engine into pressurized air. The compressor sucks in large amounts of air into a confined space under pressure. This compression increases the pressure of the stores gas, producing tremendous amounts of energy upon release, enough to power a wide range of applications.
You can find compressors in hundreds of industries for a broad range of functions. You will find the device in DIY tools such as paint sprays; pneumatic tools such as impact wrenches, nail guns, drills, tire pumps, and sanders. Air compressors also serve large industrial uses such as refrigeration, air conditioning, pumping gas and crude oil through pipelines, jet engines, and many other areas.
Before now, most air compressors were large, heavy equipment used only in factories and large workshops. But advances in technology have created miniature air compressors used in everyday activities. The air compressor comprises a compressing unit and a receiver tank that stores the pressurized gas and controls the pulsing of airflow.
Types of Air Compressors
There are two main types of air compressors including:
- Positive displacement air compressors: This can further be divided into:
- Reciprocating air compressors including the piston styled compressors
- Rotary air compressors such as the rotary vane and helical screw
- Centrifugal air compressors (dynamic or kinetic systems)
Let’s look at some air compressor systems.
Positive Displacement Air Compressors
Reciprocating Air Compressors (Piston)
This air compressor is piston-powered. The air compressor features a piston that compresses and displaces air within a cylinder and releases the pressurized air through a valve into tanks. If the reciprocating air compressor works with one side of the piston, it is called single-acting.
A double-acting reciprocating air compressor uses both sides of the piston to compress the air. These compressors can also have pressure ranging from 70 to 100 psi in single-stage units and 100-250 psi in two-stage models.
Reciprocating air compressors feature in a wide range of applications and are available in lubricated and non-lubricated versions. The unit can either be water-cooled or air-cooled.
Helical Screw Compressors
These rotary devices use geared meshing male and female rotors. When the screws turn, the system draws air into the compartment while reducing pressure. The compressed air discharges through a port at the end of the compressor.
Because of the rotary mechanism of this device, it produces less vibration and noise than a reciprocating unit. Plus, the air it produces does not pulsate and is perfect for oil-free applications.
Rotary Sliding Vane Compressors
Another type of positive-displacement compressor, sliding vane units comprise a system of a rotor, stator and blades. The device compresses air with each rotation of the rotors, producing oily air because the vanes glide through an oil film. While the sliding vane compressor cannot produce oil-free air, it produces cleaner air compared to reciprocating compressors. Further, this unit does not pulsate, is quieter and more reliable.
Centrifugal compressors use high-velocity spinning impellers to drive gases for increased pressure. You can find these appliances in industrial applications such as in commercial refrigeration and processing plants. They can work continuously and handle large volumes of gas. Common uses for centrifugal compressors include oil-free applications in commercial refrigeration and the petrochemical and natural gas industries.
Unlike pumps that are mostly centrifugal, most air compressors operate on the positive-displacement principle. Air compressors come in different sizes from the small models that power your tires to giant turbo-compressors used in industries for heavy-duty pneumatic applications. Air compressors can be electric/gas, oil/oil-less, and low/high a pressure, portable or heavy-duty, but they serve vital functions in our lives.
What Is an Air Compressor Used for?
An air compressor is versatile. It is an important tool in manufacturing, construction, mining, agriculture, and DIY projects. With some creativity, you can use an air compressor for almost anything.
The Amish people who are predominantly farmers are one of the best users of air compressors because they shy away from electricity. Amish women have been recorded using air compressors to power kitchen appliances such as refrigerators, blenders, mixers and more!
Here are other ways you can use air compressors
Power Small Tools
Many of your DIY tools use air compression. Your impact wrench, drill driver, nail gun, and many others can run on the pneumatic energy from air compressors. A pneumatic nail gun or impact drill does not rely on electricity as it runs on compressed air. With such tools, you don’t have to worry about mobility or power issues as you work in and around the house.
Flat tires are inevitable regardless of the road condition. When that happens, air compression from the small tire pump helps inflate your vehicle or bike tires. Whether you operate tractors or trucks for construction work, having an air compressor makes it easier to inflate your tires to the correct PSI when you run flat.
A spray gun makes light work of painting projects. Whether you work in an auto workshop or prefer to touch up your buildings and machinery, spray painting is faster and more effective than a roller or brush. Many DIY enthusiasts rely on the spray gun which uses an air compressor to discharge the paint evenly on the work surface.
Compressed air is used for domestic and industrial cleaning. You can use air compressors to rid of greasy stains on tires or walls, remove debris on your driveway or gutters and more. Compressed air cleaners such as leaf blowers and other specialized equipment make your cleaning tasks faster and easier.
Hospitals also use air compressors to deliver oxygen into the human body. Doctors use this when a patient cannot breathe properly. Sometimes, doctors use air compressors to provide normal air to the patient if they are sensitive to pure oxygen.
Refrigeration and Air Conditioning
Air compressors are a vital component in cooling systems such as refrigerators and HVAC appliances. Whether small or large, domestic or industrial, every weather control unit uses air compression.
Do you love bouncing castles? That’s the power of air compressors in action. Compressors force air into balloons to inflate them so you and your kids can have all the fun in the world.
Air compressors have applications in hundreds of industries from agriculture, construction, petrochemicals, automobile, to defense. The only difference is in the scale and complexity of the air compression system.
For personal use, a small-sized compressor is perfect for your needs. If you want to buy a compact and affordable unit, check out our comprehensive air compressor buying guide for the best brands.
How Does an Air Compressor Work?
How does your air compressor work? Whether you own a small unit or use a large industrial air compressor, they all work with the same principle, although there is a little difference in design.
An air compressor converts electrical or mechanical energy into compressed air energy. The pressurized air stays in a compartment until you are ready to use it. This machine will continue to power your tools or do a task so long as the compressor tank has enough air pressure.
To have a better understanding of the operation of an air compressor, it’s important to know the components of the device which includes:
- The air compressor motor or engine
- Air compressor tank
- Air pump
- Pressure valve
- On/Off switch (where available)
What are the Components of an Air Compressor System?
The Air Compressor Tank
Perhaps, the tank is the most important component of this device. It stores the compressed air under pressure and releases it whenever you need the stored energy. The operation of an air compressor starts from the electric motor or gas/diesel engine. An electric motor or engine sends electrical or mechanical power to the compressor pump. This allows the pump to force air into the compressor tank.
An air compressor motor pumps air when the compressor tank’s pressure falls below the pressure switch cut. The pressure switch cut is the maximum pressure at which the device will stop working. When the air pressure falls below this point, the motor or engine pumps air into the compartment to reach the desired psi of the unit.
In units that have an ON/OFF switch, your air compressor works when you press the ON button and stops when you push the OFF button. Otherwise, the device can begin operation when you plug it in or start the engine. Besides, your compressor will not start if the tank pressure is above the pressure switch cut.
There are different compressor tanks depending on the design, size, and application of the unit, but most homeowner models are tubular or pancake styled. If the unit is a positive-displacement type, it compresses the air into the tank with the action of pistons or vanes. In centrifugal units, the compression takes place through the high-velocity motion of a fast-spinning impeller.
Air Compressor Pump
This device collects air from the atmosphere into the compressor tank. It also discharges the stored air under high pressure so you can power your air tools without electricity or gas. Air compressors used at home and small workshops have small air pumps. It is the metallic compartment above the compressor tank. Some pumps have fins on the side to increase heat dissipation as the unit can reach high temperatures during operation.
Manufacturers often cover the pump with plastic to prevent scalding, but this reduces heat dissipation. Too much heat can damage your air compressor pump and reduce its efficiency and longevity. It’s better to buy a unit with a naked metal design but you must be careful not to touch it when it is hot.
The Pressure Switch
Except units that have ON/OFF switch, most compressors start and stop working at the behest of the pressure switch. The pressure switch can be an internal unloader valve or an external unloader valve based on the design and make of your unit.
These valves monitor the level of pressure in the compressor tank. When the pressure reaches a certain level (Pressure cut out) the switch cuts off the air supply and the unit stops working. If the pressure falls below a certain level (Pressure cut in), the switch closes to allow the flow of energy to the motor. This activates the pump to store air into the compressor tank.
You need not worry about setting the pressure switch for the tank. Most units come out of the box with a preset pressure value. However, some models allow you to adjust the pressure settings to meet the requirements of different tools.
The air compressor has two pressure gauges including the Proper Air Pressure (PSI) and Air Flow (CFM). Proper Air Pressure (PSI) measures the pressure in the compressor tank while the Air Flow (CFM) shows the pressure in the tool.
The parts mentioned above are the most important components of the air compressor system. However, there are many other parts such as cylinders, pistons, crankshafts and other components that make the air compressor work. Unfortunately, this article does not permit us to cover the function of every part.
How to Use an Air Compressor
An air compressor is simple to use. The setup is straightforward and most supplies are readily available.
Use the following steps to operate your air compressor like a pro!
Safety Equipment and Supplies
While an air compressor is not in the class of a chainsaw regarding safety, you still need to take precautions. Safety goggles protect your eyes from a hot burst of air and debris while closed-toe shoes or boots ensure tools don’t drop on your legs. If your air compressor is gas-powered, it can be noisy so wear earmuffs and also tidy up the work area.
Get some oil ready if you own an oiled model. Also, have any attachments at hand if your tools require adapters to work with the air compressor. Plus, make sure you read and understand the manual before operating an air compressor.
Check the Unit
Check the unit before operation. Inspect the tank and hose to ensure they are firmly secured as this will ensure proper pressure-buildup and increased efficiency. Make sure the machine is on an even surface as it can vibrate during operation and move or fall over. Also, make sure the power switch is OFF before plugging or starting it.
Power up the Unit
The next step is to power the air compressor. If your unit needs oil to operate, check the oil level and top-up if required. Gas-powered units must have the specified fuel-oil mix to work properly if you have a 2-stroke engine. For electric units, make sure you do not activate the ON button before plugging the machine into a power outlet.
Once your air compressor is operating, adjust the pressure gauge. Air compressors require you to adjust the pressure to the needs of specific tools. But you only need to adjust the pressure in the hose, not the compressor tank.
Make sure the pressure in the tank and the hose that will power the tool is correct. Otherwise, you risk damaging the tool and the compressing unit.
Attach Your Tool to the Hose
Once you achieve the ideal pressure level, close the gauges and connect your hose to the tool with the correct attachment. Fasten the attachment tightly to the hose to prevent pressure loss. You can work with your pneumatic tool now.
Shut the Air Compressor and Pressure Valve
Once you’ve completed your project, shut the air compressor and unplug from the power outlet or switch off the gas engine. If your unit has a pressure relief valve, use it to release any unused air from the tank. Allow the machine to cool, clean and store away.
An air compressor is a lot of things to different people. It is used in DIY operations, construction, manufacturing, cooling and more. However, most people take this versatile machine for granted because they don’t know how important it is in their daily lives. We hope this article has helped to shed more light on air compressors and what you can do with one.