How to Use an Air Compressor (6 Easy Steps)
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Air compressors are nifty tools with varied applications. Air compressors come in different versions, including electric and fuel, both of which need a safe operation.
Tag along as we break down how to use an air compressor, the maintenance process safely, and choose the best to get the job done.
But before we get into how to use an air compressor, here are a couple of things to consider.
How an Air Compressor Works
Air compressors work by forcing air into a container and keeping it under pressure. They have engines that turn electrical energy into kinetic energy, just like a combustion engine works with a valve, piston, crankshaft, head, and connecting rods.
Because of the pressurized air, you can use air compressors with different tools like impact wrenches, sanders, or paint sprayers.
Most air compressors operate on positive displacement. Using this mechanism, the air is forced into the container. The more air is forced into it, the more it gets compressed until it reaches the maximum limit that turns the compressor off.
Now, there are several methods that positive displacement can be applied in compressors to force air into storage tanks:
- Rotary screw – two helical screws turn and force air into a storage tank
- Piston – The piston pump turns and pulls in the air during the downstroke, and during the upstroke, it forces the air into the storage tank through a valve.
- Vane – a turbine with slots and different blade placements pulls air and forces it into the storage tank
When gases are compressed, their temperatures increase, a phenomenon known as adiabatic heating. Though adiabatic heating is important in diesel engines that require the generated from medium compression to ignite diesel fuel, it’s not important in air compressors. As such, it needs to be dissipated or controlled. Manufacturers achieve this through water cooling or air cooling.
Through air cooling, the excess heat is controlled through cooling fins mounted on the pump housing. With water cooling, water flows through a water jacket around the pump and is cooled through a radiator. In other instances, oil is used to cool the system. The hot oil is then cooled by air or water.
Aside from this, you also need to take note of some figures, including how much air the air compressor can store and how fast the air compressor can replenish the stored air when in use. Air compressor storage tanks are measured in liters.
As for how fast your air compressor can replenish stored air, consider the power output often rated in horsepower. The measurement points to the work a motor does to drive the pump. Finally, the CFM (cubic feet per minute) is the amount of air a compressor can deliver at a specific humidity or atmospheric pressure.
If you’d like to buy another air compressor, you should learn how to determine the size of air compressor you need for your work.
Safety Precautions When Using Air Compressors
As with any equipment, air compressors can be dangerous if you don’t use them right. In addition to several moving parts, there’s an air tank packed with compressed air, which, if punctured, can blow.
With the above in mind, you should always wear protective gear, including gloves, goggles, and old clothes, especially when using other tools like chisels, grinders, and saws.
Aside from this, you should always, always depressurize any hoses and tools you are using before you connect and disconnect them. Also, operating individual tools are the recommended pressure.
When connecting an air compressor to a power source, avoid using extension cords as they could overheat and cause fires. The power outlet should have the right voltage since a low voltage won’t run the machine at its full power, and a high voltage may break the air compressor.
Note: When plugging in the air compressor, ensure the power outlet is off first.
Air Compressor Regular Maintenance
Like with all machinery, air compressors need regular maintenance to operate efficiently. The following checks ensure different parts work efficiently before use.
Even with the below tips, you should always check the owner’s manual for maintenance instructions specific to your air compressor.
Check the Cooling System
Heat is a byproduct of compressing air, and it needs regulation for efficient operation. Your first job is to understand the mechanism air compressors use to cool themselves. If it uses an air cooling system, you should find some fins on the pump. The heat generated moves to the fins, where it’s expelled. To ensure the fins are working efficiently, look out for any blockages or debris buildup. If it’s liquid-cooled, it should have fins or a radiator that cools the liquid. Whether it uses fins or a radiator, these parts should be debris-free to allow free airflow around and through them.
Clean or Replace the Air Filter
The intake air filter cleans the air sucked into the air compressor. Over time, the filter gets clogged, causing the air compressor to work harder to suck air into the air tank. Eventually, this causes strain and leads to higher electric bills. For maximum performance and efficiency, replace or clean the intake filter regularly.
Drain Moisture or Condensate
As outside air is sucked into the air tank, moisture collects. Moisture buildup in the tank uses up space compressed air would have occupied. To maintain full tank capacity, drain the tank regularly. Many compressors have a drain valve at the bottom that you can open to drain water. But before you do this, ensure you drain compressed air first.
Check Valve and Hoses
Whether the pump is flexible or rigid, it’ll wear out with time. Air hoses become brittle and weak with constant use. Eventually, they might develop cracks along their length, leading to air leaks making it hard to maintain the required air pressure. You must inspect and replace any damaged hose. In the case of a rigid air hose, it can get corroded, leading to air leaks or high air pressure on the joints.
Check and Change the Cooling and Pump Oil Level
This only applies to compressors that have oil cooling systems or that run on petrol or diesel engines. Just like your car’s engine oil level needs regular checking and replacement, your air compressor does too. Generally, check the engine oil levels before using them to ensure the motor is lubricated and well protected. Check oil levels for the oil cooling system before turning on the compressor to avoid overheating, which could cause a lot of damage. When replacing oil in the system, refer to the owner’s manual to know the correct amount to use. If you use the wrong oil or incorrect amount, you could cause damage.
Check and Replace the Drive Belts
Like with the valves and hoses, rubber drive belts wear out with time. In some extreme situations, they could snap. Aside from this, the rubber belts can stretch, affecting how the compressor motor drives the pump and causing inefficiency.
Aside from regular maintenance, you should also ensure the moving parts are well lubricated for efficient operation. You can do this easily by inserting a good amount of lubricating oil into the hose connected to the pneumatic tool. Hold the tool upside down for the oil to travel into the moving parts needing lubrication.
Air Tanks Have Limited Lifespans
Unfortunately, air compressors have limited lifespans. Draining the tank helps to extend it, but eventually, it might burst. Check the label for when you need to replace the storage tank.
How to Use an Air Compressor
Now that you know how an air compressor works and the safety precautions to take, it’s time to learn how to use them. If this is your first rodeo, it might seem difficult and dangerous. However, if you use them correctly, air compressors are safe and make work easier.
1. Connect the Hose and Your Pneumatic Tool
After doing the initial checks, it’s time to connect everything you’ll use.
Put your compressor in a well-ventilated space and on level ground. We cannot stress the importance of working in a well-ventilated room. The air will be compressed and also work as a coolant.
Afterward, unravel the hose, ensuring that it lays down without kinks that might restrict airflow. The size and type of your compressor will determine where you connect the hose.
For a large compressor, you’ll have to plug into a regulator, filter, and lubricator. These units are either built into the compressor or fixed separately. The filter, regulator, and lubricator help air filtration, adjusting pressure, and releasing oil droplets along with air to help lubricate moving parts.
If you have a small compressor, you most likely don’t have this setup. Instead, you only have a regulator valve complete with a pressure gauge to deal with. But if you don’t have to connect it directly to a tank valve, consider getting a filter regulator and lubricator valve, as it’ll help improve the compressor’s durability.
Back to connecting the hose; connect the female end to the male connector on the air compressor. As you push the female connector, it should click and lock into place. When you hear the click, the hose is connected securely.
Once the air hose is in place, connect the pneumatic tool to the other end of your hose. The connection process is often the same as that of the air compression.
2. Turn the Compressor on and Pressurize the Tank
With the pneumatic tools and hose connected, ensure the air pressure release valves are closed before you turn it on. With that final check, it’s time to start building the air pressure. Plug the compressor’s power cord into the main socket and turn the compressor on. If the compressor has the main power switch, turn it on as well.
At this point, your air compression should be alive. As it runs, watch the main storage tank’s pressure gauge. When the compressor automatically shuts off depends on the size of its tank. Read the user manual to know at what pressure this should happen. If it doesn’t shut off at that point, turn it off at the mains and take it for service.
Some air compressors have an air pressure release valve that kicks in and opens when the pressure falls to a specified pressure. Anticipate the closing and opening to avoid getting shocked.
3. Pressure Gauges
Air compressors and other pneumatic tools that use pressurized gas, oil, air, or any other medium have pressure gauges to indicate what’s going on inside.
Most air compressors come with two gauges. One displays pressure inside the tank, and the other displays pressure of the medium coming out of the tank into your pneumatic tool. Both pressure gauges have two sets of readings, including PSI and Bar.
In most cases, you’ll deal with PSI. Generally, the higher the pressure, the higher the needle in the gauge rises.
4. Check Operating Pressure and Set the Pressure Regulator
Before you start using your pneumatic tools, confirm the correct operating pressure. This figure should be recorded in the manual or the power tool itself. Running power tools at the wrong pressure will lead to damage to the air compressors and power tools. Now, pneumatic tools operating pressures are often given in PSI.
After determining the correct pressure to use with your pneumatic tools, adjust the air compressor’s pressure regulator valve to match the pressure recommendation. The smaller gauge next to the regulator will show you the pressure leaving the compressor into your power tool.
5. Complete the Job
Now that you’ve set up the air compressor and your pneumatic tool, you can start working.
Note: the tool you use and the size of your compressor will determine how much work you can get done.
For instance, air sanders need prolonged use to complete a sanding project in good time. So as you sand, the compressed air from the air compressor tank reduces. When the compressor senses low-pressure levels, it comes to life and replenishes the air in the tank.
If the storage tank is large enough, you’ll have enough air to act as a buffer and allow continuous operation as the compressor replenishes it.
But if you use a small storage tank, there are higher chances air in the storage dank will drain faster than can compressor can replace it.
Therefore, it’s important to consider the pneumatic tools you’ll use to guide you on the size of an air compressor to get.
6. Shut Off the Compressor and Store It
Once you are done with the air compressor for the day, you should pack it and store it safely. This is important to ensure safety and preserve durability. This is how you do it.
First, turn the mains off and pull out the compressor’s plug. Wrap the cable nicely and hang it on the compressor neatly.
Next, shut off the pressure regulator valve by turning it clockwise to stop the compressed air from moving into the hose. Next, run your pneumatic tool to drain the remaining air.
Disconnect the power tool from the compressor hose and then disconnect the hose from your compressor. Make sure to wrap the hose neatly without kinks or unnecessary kinks.
Let’s take a step back. When connecting the hose, you noticed the spring-loaded locking collar on the hose ends. These collars allow you to make an easy and fast connection and disconnection between the hose and other tools. At the same time, they ensure the connection locks well without the risk of pressure sipping out.
Hold the hose or the tool firmly in one hand and pull the locking collar back with the free hand when disconnecting. A light tug should do the trick.
Once everything is disconnected, drain the remaining pressure in the compressor tank and empty the condensate buildup. Some compressors are designed to expel remaining pressure in their storage tank after turning them off, but some aren’t. In the case of the latter, you have to do it manually using the pressure release valve.
The pressure release valve is located on the tank (the manual should direct you). With a spanner, turn the valve slowly until air starts to escape with a hiss. Continue turning the valve slowly until all the air expels. Do not be tempted to release the compressed air fast as it could cause an accident.
Next, expel moisture buildup in the storage tank through the condensate valve. This drain valve is often located at the bottom of the tank.
Release the condensate valve and keep it open until all the water flows out. Refit the drain valve properly to prevent air leaks on your next use.
And just like that, you are done. Store the compressor in a safe space for your next use.
Now that you know how to use an air compressor, you should be more confident to operate it safely. Remember to maintain it regularly, to get the best from it.
I’m Ruiru Kibet, an avid writer and techie that has taken a keen interest in offroading. As I explore nature and troubleshoot with different offroad products and techniques, I’ll share them with you. The goal is dumb it down and help you experience the best of nature.