This blog entry is to assist those who are either buying an air compressor for the first time or replacing an existing air compressor that has worn out or broken down. It lists a few of the basic things you should consider when choosing an air compressor, with some supporting information on how these interact.
Air Demand
When choosing an air compressor, you need to know what the air demand is going to be at any given time. For example, it might vary between shifts. This air demand will be determined by the air tools that you are using. When we say “air demand”, we are talking about both air consumption/air flow as well as air pressure.
Air tools have a specification for air consumption that is normally given in either litres per minute (l/min) or cubic feet per minute (cfm).
Air tools also have an operational pressure given in bars (b) or pounds per square inch (psi). Most run at a maximum of 90psi. However, it’s a good idea to have a compressor that will produce a higher psi than required, because the pressure will drop as it’s used. A rule of thumb is to have about a third more psi than you need, or about 120psi. This way, you’ll be assured of consistent pressure.
Put simply, if your air compressor doesn’t meet the air demand of the system, then the air tools will not function effectively.
Storage/Tank Size
The next thing those buying an air compressor or replacing an air compressor need to consider is the amount of air that can be stored in the compressor tank.
A larger tank obviously means more compressed air available for the air tools, allowing them to operate for longer before the pressure drops. The downside is that the size and weight of bigger tanks makes them harder to manoeuvre.
While smaller tanks are more portable, they cause the compressor motor to have to worker harder to meet the demand. This leads to increased engine noise, which can be a real problem in, say, medium-high density residential areas where health and safety regulations severely limit noise levels. Fortunately, very quiet air compressors are available for such situations.
Other Considerations
Space: The number-one limiting factor on the size of the air compressor is the available space in which to store it.
Energy: Energy consumption must also be considered when choosing an air compressor, especially in terms of the overall load of your production line/factory.
Ventilation: There must be sufficient ventilation (fans, etc.) for your chosen model of air compressor to operate at peak efficiency AND to allow heat to escape from the space where it is positioned.
Air quality: The desired air quality will depend on the tasks your air tools are performing, with different industries demanding purer air. Water, oil and other particles are the three types of contaminants that should be filtered from the air.
Oil or oil-less: Oil-less air compressors make more noise than those which use oil, because the piston is usually small and runs faster than an oil-lubricated piston. Again, noise can be a major problem on certain job sites.
Buying an Air Compressor or Replacing an Air Compressor?
For all of your compressor requirements in the south-east Queensland region, don’t hesitate to contact Cospaker Pneumatics. You can email us at carey@cospaker.com.au. Or you can find the phone numbers for our Gold Coast, Brisbane, Beenleigh and Tweed Heads offices on our website here.