Different types of compressors have been invented over the years, and many ways have been introduced to compress the gas. Air compressors and tools play a huge role in our residential and industrial processes.
It plays a more significant role because of its ability to produce clean, contaminant-free air required for aerospace devices. Regardless of type, the primary function of the air compressors is to produce compressed air after the conversion of power into stored energy.
Based on the internal mechanism, four types of compressors are commonly used. We will explain in-depth detail for understanding work mechanisms and the benefits of the types of compressors. Each of these compressors has its unique proficiencies and limitations.
Types of Air Compressors
Each of these compressors has its unique proficiencies and limitations. After going through the article, you can decide what type of air compressor is best for you, depending upon the pressure of the air you will need for your tasks. Here are the best air compressors we have reviewed so far.
Categorization of Air Compressors
There are two main categories of air compressors, namely positive displacement, and dynamic displacement. In a positive displacement air compressor, the required amount of air is trapped from the outside in a chamber. This compression chamber reduces the volume, which as a result, raises the pressure and potential energy.
Dynamic displacement is opposite to the positive displacement air compressors. These, when encompassing the air within them, speed up the air to a higher velocity. They also restrict the air so high pressure is created while the kinetic energy in the compressor remains static.
Rotary Screw Compressor
These fall under the category of positive displacement compressors and are most commonly used. Rotary screw compressors are equipped with an internal cooling system and are the easiest compressors to use.
Two internal motors are placed in these compressors that generate energy while rotating in opposite directions. The pressure is built when the air is trapped between the huge opposing motors. These are designed to run continuously without any interruption and have a 60 percent of duty cycle.
They do not heat up because of the cooling system and are a lot more quieter. These rotary compressors produce air that dries up quickly and might use a lubricant for some applications. A synthetic product or hydrocarbon can be used as a lubricant and can affect speed and direction.
While in the dry type, there is no contact between the rotors, and they use external lubricated timing gears. The rotary screw compressor can produce power ranging from 5 horsepower to 350 horsepower. Hence these are best for industrial use because of their vast size and air purity.
Reciprocating Air Compressor
Reciprocating air compressors are ideal for home use and small working projects. The rotating air compressors are not designed for continuous use and are lubricated with oil for smoother movements. They comprise many moving parts, and it is essential to care for these for efficient output.
These also fall in the category of positive displacement air compressors and are multi-stage compressors. The air is compressed and displaced because these compressors use a piston inside the cylinder. Pressure is built inside these single or multi-stage compressors, which also affects the range.
These can produce more power for intense construction purposes as they are multi-stage compressors. They can reach up to 30 horsepower during complicated applications. However, small home tasks such as woodworking or metalworking can be performed by using single-stage compressors efficiently.
Axial Air Compressor
The Axial air compressor has the highest efficiency among all the compressors, and they lie under the category of dynamic displacement compressors. These come with fixed blades, which makes them extremely expensive.
The air passes through these blades and produces kinetic energy, which in return converts to pressure. Combining the axial air compressor with the gas turbines leads to better operations with high rotation speed.
They have several rows of airfoil cascades, while some are fixed, and others are rotatable. The fixed rows are called stators, while the moving rows are called rotators. These are widely used in planes and ships and are not suitable for construction sites.
The working process of these compressors is very complex because of the different compressibility effects. Pressure variation is observed in each blade, whether stator or rotator. However, these performances can be evaluated based on the pressure ratio, rotational speed, and efficiency.
Centrifugal Air Compressor
The Centrifugal air compressor has a radial design and falls under the category of a dynamic displacement compressor. Their performance can be affected by the changes in temperature as they work at constant pressure. They use centrifugal force for the air into the center for the rotation of the radial blades.
As a result, air pressure rises, and kinetic energy is produced. This energy is easily converted into pressure after it passes volute and a diffuser. Several stages can be set up to achieve the required high pressure. The oil and gas industry mainly uses these kinds of applications to get the desired pressure ratio.
The centrifugal air compressors require no or very little maintenance and can produce oil-free air compared to the rotatory and reciprocating air compressors. These can reach up to 1000 horsepower and produce large amounts of energy in a relatively small machine. Also check out, how to adjust air compressor pressure regulator?
How To Choose The Right Air Compressors?
To select a suitable air compressor, looking at factors other than power generation and energy output is necessary. Several other factors also play an essential role in an air compressor, and they shall be considered before deciding. Some of these vital factors are enlisted down:
Using oil-powered air compressors in clean environments can create a big problem as they rely on oils for smooth movements. These can contaminate the environment, resulting in damage to many processes.
The risk can significantly be reduced if these oil-powered compressors are replaced with oil-free compressors. Switching to the alternatives can undoubtedly be expensive, but this is necessary to keep the environment clean from the fumes in the air.
The parts of the machine will still need oil for smooth movements, but the inner mechanism of the oil-free compressors uses different workings. This also runs low on cost because the parts do not need to get changed frequently.
Energy-efficient air compressors help you work on complicated projects as using these can add up to the cost. Two types of compressors that save energy are natural gas air compressors and variable speed compressors. These are energy efficient and have the same output as standard air compressors.
Natural gas air compressors can be used for industrial settings such as chemical processing plants or manufacturing and petroleum refineries. These consume natural gas instead of electricity or petrol and save a lot of money.
These are more efficient and have better capabilities than air compressors. These are the best alternates if you are on a budget and want to save a few bucks. The second option we have is the variable speed compressors. The output can be altered in these compressors according to the demand.
This prevents wasting of the money and energy that is produced for no good reason. Whereas the fixed speed compressors continue to work at the same rate and waste energy.
Some additional features can be added to your air compressor to facilitate the application process. An air hose splitter can be attached to the air compressor as it allows you to hook up multiple tools, so you need to connect again and again between switching tasks.
Furthermore, the addition of thermal protection protects the machine from overheating. Quieter operations can be achieved by attaching belt drive systems. For adding these additional features, your machine must be compatible with these tools.
Frequently Asked Questions
How many types of air compressors are there?
The air compressors are categorized into two categories, i.e., positive displacement compressors and dynamic displacement compressors. Both of these air compressors have different working mechanisms to produce compressed air.
What type of air compressor is best?
The best type of air compressor is the reciprocating air compressor because these can be used continuously without any interruption. These are multi-stage compressors and have enough capacity.
What fluid is used in a compressor?
The oil and lubricants from the compressed air systems are used in the compressors for smooth movement. These are used to carry out the mechanism of the machine and keep the parts functioning for long periods.
What motor is used in a compressor?
The three-phase squirrel cage induction motor is used in a compressor as it is quiet and does not produce noise while the operations are being done. These are very much reliable and commonly used for industrial purposes.
Watch the video about all types of Air Compressor
Different types of air compressors, along with their categories, are mentioned above. This explanation will help you better understand the air compressors as it did for me. Air compressors increase productivity and are reliable air tools. Four major compressors and their unique working mechanisms can widely be used in our daily lives for multiple purposes.