UK Construction Blog

Air Compressors in Construction: A Full Guide

Air compressors are an essential aspect of the construction industry. You might be aware of them being used at construction sites for their high efficiency and output, but have you ever considered thinking about how air compressors actually work?

Direct Air have developed an insightful infographic detailing how they operate and the different types of air compressors that are available to use. 

Using Air Compressors in Construction

Air compressors are integral to the construction industry as they power a vast amount of tools a worker needs. The great aspect about pneumatic drills is that they are relatively light and powerful to use, allowing great amounts of energy to be exerted.

Compared to electric powered tools, pneumatic tools are safer to use and easier to maintain as there is not a risk of electrocution.

Some of the most popular construction application use comes in the form of jackhammers, pneumatic picks, air guns and many more.

It is important to emphasise the value of maintenance because failure to maintain tools regularly will lead to them deteriorating and not working properly.

Low Noise Air Compressors

Construction site managers need to think not only about the welfare of themselves but also of other fellow employees.

Workers should wear ear protection to protect themselves from hearing damage. Anything above 85dB is considered to be harmful and likely to cause hearing issues.

Air compressors can control and reduce noise levels, when generating power for equipment.

While 60 dB is considered a safe level, there is no reason why you should not be able to reduce the noise levels even further.

Low noise air compressors can decrease noise levels to around 40dB, of which this is accomplished through the addition of an acoustic chamber which function consists of containing the noise.

An additional tip to help reduce noise levels would be to choose an electric-powered compressor, rather than a gas-powered machine.The electric compressor’s power source can make a machine generate less noise.

Oil-free and Oil-based Air Compressors

Lubrication is an aspect that should be reviewed when using an air compressor.

Compressors that are oil-free already have a lubricated cylinder, mainly Teflon, thus ensuring no further maintenance is required.

Oil-based compressors require manual work as oil needs to be added to the piston area frequently, and how much depends on the instructions provided in the manufacturer’s manual that came with the compressor.

Oil-free compressors are lighter than oil-based compressors as the weight of the oil is not required and there are less parts to make them function.

Furthermore, oil-free compressors tend to be more affordable than oil-based compressors and usually have a less complex design.

Despite costing more, oil-based compressors are stronger and tend to have a longer lifespan than oil-free ones. Over time the material that is used for greasing, which is primarily Teflon, starts to wear out and endures a loss in its abilities of lubrication.

In comparison to oil-based compressors, oil-free compressors heat up at a higher temperature and tend to make more noise.

How do Single and Dual Phase Compressors Operate?

For single phase compressors, compression occurs within a vacuum excavation system by a single piston movement.

The power is measured at a rate of PSI (pounds per square inch), of which the higher the PSI rate, the greater the power the compressor has.

In a single phase compressor, the PSI rate is usually at 120. Once the air has been compressed, it then gets sent into a storage tank. 

For Dual phase compressors, following the primary round of compression, air is dispelled into a second chamber at a rate of 175PSI, where the air gets compressed for a second time.

The piston forces movement allowing compression to occur, as both types of compressors are usually powered by electric or power motors.

Fixed and Variable Air Compressors

Fixed speed air compressors send continuous streams of power into the motor.

It’s great for certain industries where power demand is continuous. However, while being cost-effective, they are not energy efficient.

Variable speed compressors automatically adjust the motor speed in conjunction with air demand.

Power gets drawn into the convertor and converts AC power into DC power. A capacitor cleans the AC and converts it into DC using a transistor, acting as switches. This then ensures the power’s frequency is controlled that is distributed to the motor, thus also controlling the speed.

Variable speed compressors are more power efficient as you can control the output of what you need, which means that if you were to use less power, money would be saved and it would be more beneficial for the environment.

Unfortunately, maintenance repairs are frequent and there are higher capital costs. This compressor type is not recommended for machines that require streams of power that are continuous.

Piston, Scroll and Rotary Screw Compressors

Scroll compressors are a type of piston compressor, also known as reciprocating compressors.

The piston travels downwards, following pressure in the cylinder being decreased which creates a vacuum. This pressure change causes the cylinder door to open and draw air in. The piston then travels back up forcing the air to be released from the cylinder at a higher pressure point.

While they are able to cool down quickly and are energy efficient, they are harder to maintain and initial costs are high.

Rotary screw compressors use rollers to compress air. These are positioned in the middle of the shaft and one side of the rollers are constantly in contact with the wall, and they rotate an extreme speed.

Despite costing less, rotary screw compressors require frequent maintenance checks and cooling ability is quite limited.

Overall Thoughts

When choosing an air compressor that is needed for a particular job, there are vital aspects that need to be reviewed.

Do you require air compressors for continuous use of industrial machinery or only occasional use?

It is important to think about the budget because some compressors will be more cost-effective than others, and you need to consider how much maintenance work there will be in the future. Failure to maintain tools regularly will lead to them malfunctioning.

With all of this taken into consideration, you should be able to make an informed decision on selecting the right air compressor for the required job, one of which is the most suitable for saving your company money and being energy efficient.