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.