Using an ultimate power source was common about some years ago that was used as a central system to run all the other tools through different systems like belts or wheel and driveshafts. The whole system was driven by a mechanical system to run actively. However, now the age of belts and such tools is gone, people are still using the old system with an air compressor that uses the storage of compressed air as the main source of power. This system uses the compressed air to convert the power of electricity into the power of action or to perform different functions. The compressor releases the air in a high speed that produces a large amount of energy needed for a number of functions. One can use this machine for almost all the works that are done by air; hence it is gaining popularity amongst people and in the workplaces. Air is a completely safe resource and can be conveniently used for different purposes. It has the capability to replace all the other air tools and its efficiency has a limitation only in your imagination.
Types of air compressor:
There is a wide range of compressors available in the market and it is quite tough to decide which one is the best. It completely depends on what are the tasks you are intended to perform. Every compressor has its own use and functions and all the features of that compressor serve individual purposes. Air compressors can be classified into two types based on the principle of operation.
- Positive Displacement
- Roto-Dynamic Compressors
Further classification can be done on Positive displacement compressors into two categories:
- Reciprocating and
- Rotary compressors.
Under the classification of reciprocating compressors, we have
- In-line compressors,
- “V”-shaped compressors,
- Tandem Piston compressors.
- Single-acting compressors,
- Double-acting compressors,
- Diaphragm compressors.
The rotary compressors can be classified into the following types:
- Screw compressors,
- Vane types compressors,
- Lobe and scroll compressors and other types.
Roto-dynamic compressors can be classified into the following types:
- Centrifugal compressors, and the
- Axial flow compressors.
The most common types of air compressors that are commonly used today are:
- Reciprocating or piston compressors
- Rotary screw compressors
- Rotary Sliding Vane Compressors.
- Centrifugal Compressors.
(Reciprocating, Rotary Screw, and Rotary Sliding Vane are all positive displacement compressors)
Reciprocating or piston compressors:
Reciprocating or Piston compressors are the most available compressors commonly used on the market. This type of positive displacement compressors has a very high range from fractional to a large range of horsepowers. Positive displacement air compressors perform their function when air chamber is filled with air. After filling the chamber, it reduces the chamber’s volume. You must be familiar with the working procedure of an internal combustion engine. This reciprocating compressor just follows the same system, but in an opposite direction. They generally come with pistons, valves, cylinders and housing blocks to run the system.
- The design is simple
- The initial cost is lower
- Installation is quite easier
- Allows efficient performance by the two stage models
- Offers a great range of horsepowers
- It can be highly effective in reaching maximum pressure.
- Maintenance can be very expensive
- Can be a bit noisy while performing
- Different foundations are needed for different size.
- Only some limited compressors may reach the maximum capacity while performing.
Rotary screw compressors
They are also positive displacement compressors. By filling the void between two helical screws and their storing with air, Rotary screw compressors perform their function. To keep it cool and maintain the lubrication between the housing wall and screws, injection of oil is done in these compressors to avoid internal leakage. Oil is injected into the compression and bearing area as well. While working with these compressors, it is important to separate the air from the oil to use the air for other systems when the cycle of compression is done.
- Design is not complicated
- The initial cost varies between low to medium range
- The maintenance cost varies between low to medium range
- Installation is quite easy
- Moving parts are few
- The design is quite popular in plants.
- The rotational speed is too high
- Expected life is shorter than others
- Single-stage design is not really efficient
- Aired life is limited and not suitable for field services
- The initial cost is high in two-stage designs that are oil free.
- In unsuitable or dirty condition, it may cause difficulty.
Rotary Sliding Vane Compressors
Like the other two types of compressors, Rotary Sliding Vane Compressors are also positive displacement compressors. The pump includes 8 blades with a rotor and stator. The rotor provides a crescent shaped area by its arrangement in the stator to rotate like a swept area between the exhaust and intake ports. The rotator completes a rotation for a single revolution to achieve the maximum volume at the intake ports and a minimum volume at the exhaust port. To keep it cool and maintain the lubrication of the bearings and vanes, as well as providing a seal within the stator wall and the vanes, injection of oil is done in the stator areas and air intake. Like the other compressors, a separation of oil and air is necessary to transfer the air as the cycle of compression is complete.
- No complication in designs
- Installation is quite easy
- Maintenance cost is low enough
- Airend is serviceable enough for the field
- Moving parts are few
- Expected life is long for airend
- Efficient in unsuitable or dirty conditions as well
- Not very efficient for single-stage designs
- Users may face difficulties while working in high pressure
- There’re no available oil-free designs
- Oil carryover comes with oil-injected designs
Like the other three compressors, Centrifugal compressors are not the positive displacement type of compressors. Impellers with high speed are used speed up the air and then they use the diffuser to do the reverse action. The system that uses a high speed to increase the air pressure is known as Dynamic compression. You will find a couple of impeller and diffuser combinations in most of the centrifugal compressors. These compressors are featured with intercoolers at every stage to decrease the temperature of the air as well as preventing any further damage of the impeller that may assist with erosion.
- It can reach up to a high pressure
- No further foundation is required
- Highly efficient for performing heavy tasks
- Perfectly packaged for plant and instrument air.
- The designs allow air that is lubricant-free
- The initial cost is too high
- Monitoring and control system is highly complicated
- Special bearings and clearance monitoring are required for a high speed of rotation.
- It needs a special maintenance and control system
Other aspects of classification: The compressors can also be classified based on other aspects like
Based on Number of stages: Three stages of compressors are found. They are-
- Single-stage compressors
- 2-stage compressors and
- Multi-stage compressors
Based on Cooling method and medium:
- Air cooled,
- Water cooled and
Based on Drive types :
- Engine driven,
- Motor driven,
- Turbine driven,
- Belt, chain, gear or direct coupling drives
Based on Lubrication method
- Splash lubricated
- Forced lubrication
- Oil-free compressors
Based on Service Pressure
What Need To Learn Before Buying Air Compressors:
- Absolute Pressure: It is the total measurement of atmospheric pressure and gauge pressure. It is measured from absolute zero.
- Aftercooler: It is the part where heat dissipated from an air compressor that removes moisture from gas or air.
- Air-Cooling System: This is a system that allows the machine to reduce temperature and to enable the motor run for a long time.
- Air Receiver: It is the storehouse/tank of the compressed air that also delivers the air.
- Atmospheric Pressure: This is one important thing to consider while working on a project at high altitudes.
- Brake Horsepower: This is to determine the total amount of power that is necessary to compress a required amount of air as well as to deliver it.
- CFM: CFM is the abbreviation of Cubic Feet per Minute. This is the measurement of the volume of air over time.
- PSI: It is the abbreviation of Pounds per square Inch to measure the pressure or force of the air.
- Roll Cage: It is the protective cage to ensure no further damage to the compressors.
- SCFM: Nowadays, Manufacturers are often looking for using SCFM more than CFM as the measurement of the volume of air is done at a fixed temperature (60° Fahrenheit) to avoid fluctuation of temperature at different conditions. It is the Standard Cubic Feet per Minutes.
- Thermal Overload Switch: This switch ensures an extended life for tools by shutting off the motor automatically when it crosses the heat limitation.
- Unloaded Horsepower: This is the measurement of power that has been used to overcome the loss of friction that may happen while working in an unloaded condition.
How to choose air compressor
To choose a compressor, first of all, you need to decide what will be the use of your compressors. Ask yourself if you have any specialized needs to fulfill with the compressor. If you need a lot of pressure, it will be useless to buy a piston-type compressor because piston-type compressors are useful if you need an oil-lubricated compressor to use only a small amount of air. You can also go for oil-free piston type compressors if you need an oil-free air, although they come with a high price than the others. A rotary screw compressor can be the best option while looking for operating several machines with increased amount of air. It solely depends on the individual purpose or function of the compressors and then you can buy the one with the right features. It will be wiser to check your tools and the amount of air you need from your compressors. To make it easy for you, we have narrowed down the requirements for you to consider while buying air compressors. Follow the steps:
- Determine your need: Determining your need is the first thing to consider before buying air compressors. You can use air compressors for heavy industrial works and for that you need to buy piston-type air compressors with the tank to perform heavy functions. However, you will want to avoid the tank to carry it easily if you have simpler requirements.
- You need to consider pressure and at the same time volume of the air compressors according to your requirements.
- It is suggested to buy high-pressure efficient air compressors to perform with heavy-duty tools for industrial use, with a capacity of storing a large volume of air.
- If you are intending to perform a lighter task, air compressors with low to medium capacity pressure and volume can be useful.
- Choose your Type: You can choose from piston-type air compressors or portable compressors. Piston-type compressors are two types mainly depending on the piston. Single-stage piston type compressor delivers less continuity in air supply than the two-stage compressors that have two pistons to deliver more continuous supply. You can also choose between portable one and compressors with the tank.
- Single-stage compressors are more useful for lighter tasks or heavier tasks that are performed at home.
Two-stage compressors are used mostly in industries to make a continuous supply while working on the project.
While working at home, you need something easy to carry and transfer from places to places, so it is suggested to buy a portable one without a tank.
For heavy industrial uses, piston-type with the tank will be useful to store a large volume of compressed air.
Look for specific considerations?
- Horsepower: One of the most important things to consider is the horsepower of the air compressors that vary from 1.5 HP to 6.5 HP. You can use air compressors with small scale horsepower to perform lighter functions at home and or high capacity compressors for heavy industrial uses.
- PSI and CFM : These are two major measurement units that are considered for an air compressor. These units help to determine how effective your air compressor is in heavy and lighter conditions. Finding out the necessary requirement of your tools that you will be using is the key to determining the right PSI and CFM for you. It will be wiser to select the air compressor that has higher PSI and CFM capacity to ensure the best performance. You can select your necessary PSI and CFM by determining the PSI and FM of your tool (if there’s one tool) or the total PSI and CFM of your tools (If you have multiple tools to run). It is suggested to buy 1.25 to 1.5 times more airflow from your requirements or the range of the tools that will further help you to continue your work and ensure the best result.
Some popular air tools with their average CFM requirements at 90 PSI:
To help you narrow down your choice and to help you select the right one with exact requirements, here are some of the important air tools and their average CFM requirements:
- Brad Nailer- .o3 CFM
- Chisel or hammer- 3-11 CFM
- Drill, reversible or Straight-line- 3-6 CFM
- Dual Sander- 11-13 CFM
- Framing Nailer- 2.2 CFM
- Impact Wrench- 1/2” 4-5 CFM
- Impact Wrench- 3/8” 2.5-3.5 CFM
- Orbital Sander- 6-9 CFM
- Ratchet- 1/4″ 2.5-3.5 CFM
- Ratchet- 3/8” 4-5.5 CFM
Get to know the availability of your power source: Power source or electrical outlet is to decide whether you have a continuous power supply or lack of it. Air compressors also vary with this feature. Electric motors are the best option if you have a continuous supply of electricity while working on a project. Go for a compressor with gasoline engine if you do not have an electric outlet near your workplace or no such guaranteed power supply. Most of the air compressors allow you to choose from different voltage limitation from 110V to 240V. Choose according to your need.
Choose from tank size: You have options to choose from different tank size according to the need. Larger tanks are often useful to continue your work for a long time when working in a heavy commercial project while you may prefer a smaller one for using a nail gun or something like that.
What can it be used for?
There are so many uses of air compressors that it cannot be listed perfectly. Some of the uses are even unknown to people. However, with different uses, a lot of options are available for air compressors
1) Cleaning up quickly:
- Help you cleaning up quickly
- Air blow guns help you drive away debris.
- Help remove any kind of a mess within a very short time.
2) For home shop:
- Help blowing up balloons or inflatable products
- Adding air to tires on bikes and on vehicles
- Useful for cleaning services and tight spaces on equipment or other durable items with directed air pressure
- Painting with an airbrush for small precision projects or on larger surfaces
- To get help using various air tools for home projects
3) Applications of air compressors in small- and medium-sized businesses:
- To Paint vehicles in an auto body shop
- Sanding in an auto body shop or in woodworking
- To make snow at ski hills or for entertainment uses
- To use pneumatic nail guns for roofing
- To provide dental and medical services
- To use pneumatic drills and hammers on construction sites
- To use an air blow gun to clean machinery
- Sandblasting in a machine shop and manufacturing facilities
- To provide power to various air tools
Simply an amazing option to productive and profitable agricultural practices. It has a wide range of uses for a long time and on a low budget. It is used:
- To Move feed and grain
- To provide glass-house ventilation systems
- To spray crops in the field.
- To allow power to the dairy machines
- To enable pneumatic material handling equipment
Air compressors are an essential thing if you are connected to any kind of manufacturing job, no matter it is in refineries or plastics or fabrication of metal. If you want production, you have to use the right tools that are powered by compressed air. You need air compressors
- To operate tools powered by compressed air
- To get help in cutting and welding equipment
- To eject pieces from production molds
- To monitor overall production
- Adjusting roller and feed machinery
- Blowing a molded gas tank or plastic bottle
- To perform lighter tasks with ease.
- To use air cylinders to increase production efficiency
- To get a good finishing and packaging with different devices
- To get help in sandblasting and finishing metal
- To operate machinery that is automated
6) Dry Cleaning
You need a continuous supply of air and a reliable system that is convenient to use for this sector. Hence, an air compressor is the ideal option for you to get the best cleaning for garments.
- You can use cleaning guns to deliver chemical options.
- To operate laundry presses and steam cleaners
This is a highly regulated sector that needs high-quality air compressors to get the best performance. You need an air compressor
- To move product on conveyor systems
- To spray coatings on pharmaceuticals
- To maintain a definite pressure while mixing and holding in tanks
- To help you bottling and packaging your products
8) Energy Exploration
You need a great power source to adjust to your budget and hence, an air compressor is the right choice for you if you are in this industry. You need an air compressor
- To provide the power source for air tools and equipment
- To compensate for motion that is caused by turbulent seas
- To allow insertion and withdrawal of reactor rods
- To control valves in steam and coolant circuits
- To provide the power source for the ventilation system
9) Food and Beverage
Compressed air is the safe and reliable way and hence, it is unnecessary to describe the importance of air compressors in food and beverage industries. To get contaminate-free production, it is a must-have thing. An air compressor is used in this industry
- To get help in packing and palleting products
- To check devices and close them
- To fill drinking equipment
- To reduce temperature for production
Other uses of air compressors that may surprise you:
- As an Airbrush painting: Customizing your vehicle with small size air compressors is one of the creative uses of this machine. You can now become a painter of your favorite scooter or motorbike.
- For Skinning a dear: This one may sound quite strange to you, but yes, it is possible. You just need to make holes to
- As a Snow machine: It is time to get your Christmas back with your air compressor and make your own snow.
- As a Paintball gun: It will be fun to make your own paintball gun now by using an air compressor to apply pressure.
- For Diving: Compressed air is being used as breathing gas and for the diving purpose. You need to use the specialized one to ensure with many improved features.
- For Inflating tires: This is one of the most commonly known uses of air compressors for inflating tires that is a regular job for people using cars, cycles and other vehicles. Not everybody can repair tires every time.
- As a Pressure washer: Using high pressure to clean your cars or driveways is a fun thing to do. However, you need to be more careful while using it as it may unbalance your position. Be careful about the people around you while using it.
- As a Staple gun: The nailing gun has made the construction work easier by using both the direct or indirect drive. You can easily nail 40-50 nails easily by this gun per minute.
- As a Sandblasting tool: It is so much easier to make the surface ready for you within a short time by using this tool.
- As an Air blow gun: To blow out the dust of your machinery, you can now use an air compressor with low pressure. Using high pressure may cause damage to the machinery.
- As an Air Sanders: Air compressors can be used to sand an object smooth and more useful than the heat sanders.