Air Compressor Description
Air compressors can be used for a variety of applications from powering pneumatic tools to filling the air in a tyre. Working on slightly different methods they essentially push more and more air into a storage tank thus pressurising it, which could be an external tank or an internal smaller space that build pressure and releases it continuously. The stored air can be later used as required and also manage a more fixed pressure of airflow in case there is a specifically required capacity. The unit to measure how much the mass of the airflow being pushed out is CFM (Cubic Feet per Minute), this is not for the volume of air compressed but the mass of the air flowing each minute! Different compressors have lower or higher power ratings as some tools need a fixed low-level pressure and others possibly need the opposite. The PSI (Pounds per Cubic Inch) measures the amount of pressure a compressor can produce during compression.
The three most common air compressors are the reciprocating, rotary screw and rotary vane ones. In application there isn't much difference but how they work varies. The reciprocating compressors are often found in mobile applications as they are easier to service/repair with simple hand tools, being the most common between the 3 they are produced by many companies and are also the cheapest initial cost! The oil level in these needs to be just right as being over the level means there will be oil carry over into the air being supplied! This can ruin the tools being used or insert air into the painting gun, which will essentially ruin your work.
The rotary screw based compressors are the most expensive ones and are built to be running continuously. Known for a longer life they have fewer moving parts, this allows for the long life. rotary screw compressors also have another advantage they don't need an air receiver tank to store the air, but at the same time the downside being that they needing a specific kind of oil during maintenance to keep them running well! Rotary vane compressors also have fewer moving parts and are the smallest in size in comparison of power output. These are designed for continuous duty and provide air with very little pulsation in the flow. Rotary vane compressors are also cheaper initially even though not many companies produce these.
As the uses are many from orbital sanders or a nail gun on till spray painting it is good to take into account the purchase price, ease of use, cost of maintenance, size, availability of parts, airflow and longevity to get the right one for your work! The more powerful the tools in use are the more CFM and PSI they will require to operate at optimum levels. Regular maintenance is good if you want to keep them at maximum capacity.