Important factors to consider when choosing an air compressor

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Important Factors to Consider When Choosing an Air Compressor
An air compressor is a straightforward machine. It consists of a motor that
compresses air into a storage tank. The air can be released at a chosen
pressure when required to power a pneumatic tool. There are 10 main
things to consider when choosing one of these machines.
DIY users
Domestic users need small hand held compressors to inflate tyres, toys and
power DIY tools.
Builders and contractors
Building contractors need a tough compressor that can be hand held,
wheeled or connected to a van or other vehicle to power tools ranging from
nail guns to heavy pneumatic drills.
Commercial users
Commercial users need high performance air compressors to power
manufacturing processes and equipment. These can be conveyor belts or
offshore drilling equipment.
Power source
Domestic compressors usually run on standard household voltage from a
mains power socket. Building contractors and commercial users can use gas
or diesel powered compressors outdoors or electrical powered compressors
indoors. Large commercial users usually have their own generators for
powering compressors.

Performance
The compressor must match the tools it will power. This is the amount of air
it will deliver in standard cubic feet per minute (SCFM). DIY tools usually
needs up to 5 SCFM while larger tools need 10 SCFM and above. A standard
rule is to choose a compressor that delivers 1.5 times the maximum air
requirement of the tool.
Tank size
Air powered hand held tools need a tank size between 2 and 6 gallons. You
also need to decide between vertical tanks that take up less space than
horizontal tanks but usually are at the low performance end. Horizontal
tanks are best suited for high performance needs.
Pump
A single stage compressor has one or more cylinders each producing
compressed air at the same output pressures. These are suitable for tools
used over a short period. Two stage air compressors have two or more
cylinders. The first cylinder feeds compressed air to the second cylinder for
further compression and so on to the next cylinder. The air is stored in tanks
of the same size. This pump type suits high demand and high performance
work and to power tools that run continuously.
Lubrication
An oil lubricated compressor is heavier and larger than an oil free version. It
also requires an oil monitoring device to ensure oil levels do not fall to low.
Oil free versions are good for portable compressors.
Air hose length
Extension leads should be avoided on air compressors. If the compressor
has to stand at a distance from the tool, ensure that the air hose is long
enough for the job.

Control system
Start / stop control systems suit DIY purposes and those that do not need
continuous air flow over a long period. Use a constant speed control if the
compressor stops and starts over six times during one hour. A dual control
system allows the operator to choose between start/stop and constant
speed.