Similar to an air pump, compressors alternate between sucking in and compressing a gas. The piston sucks in the required air from the environment and compresses it in its housing, or "compresses" it, so that you can then release the air in a controlled manner.
Compression reduces the volume of the gases so that the pressure in the gas increases, enabling you to perform various tasks with compressed air.

Depending on the application, different compressors in different sizes and designs are useful.
If you use your compressor frequently and intensively, it should have an appropriately large pressure vessel to enable you to work with adequate pressure. These devices are particularly suitable for painting and sandblasting work as well as for operating pneumatic tools.
If you only use your compressor occasionally for filling tyres, balls or similar purposes, you do not usually need a device with a compressed air tank. An air compressor with a low voltage is sufficient for this purpose.
You should pay particular attention to the manufacturer and its specifications. You can find more information on this under the point "Clever selection of the manufacturer".

For the drive of your compressor you should use special compressor oil, because the lubrication has a significant impact on the operation, performance and life of your device.
Compressor oil is a low-viscosity oil, which is less viscous than engine oil. This results in less friction than other oils. I therefore advise you not to use engine oil.
Compressor oil also has a cooling effect and reduces wear enormously. I recommend a viscosity of 100, for example compressor oil VDL 100.

The suction capacity shows you how much air flows into your compressor per unit of time (seconds or minutes).
With the help of the suction capacity you can calculate how long it takes until the tank is refilled. This way you know how often the compressor has to switch on while you are working.
From the intake capacity you can also derive the so-called output capacity. With your device, you should make sure that the intake power is 30 percent higher than the output power.

If you want your compressor to support you when sandblasting, the maximum pressure should be at least seven - preferably more - bars. A high pressure ensures that there is less friction between the individual sand particles and that you can distribute the sand more powerfully with the spray gun.
The necessary maximum pressure is usually achieved by most commercially available compressors.
The delivery rate should be at least 400 to 600 litres per minute. This value indicates how many litres of air the compressor can deliver per minute.
The boiler should hold at least 100 litres. The larger the boiler, the longer you can work without interruption.

A compressor for impact wrenches should have sufficient air capacity.
You need a device with sufficient operating pressure (approximately seven to ten bar) and sufficient air flow (200 to 400 litres per minute) to cover the compressed air requirements of the impact wrench. These values vary depending on the model.
Furthermore, you should pay attention to the size of the boiler, it applies:
Compressor 50 liters: for private users (car / home workshop).
Compressor 100 litres: for hobby mechanics
Compressor 200 litres: for professional workshops
A compressor for your impact wrench should be oil-lubricated, as the fine oil film in the compressed air also lubricates your impact wrench and thus increases its service life.

If you have a classic piston compressor, it is possible that the seal in the area of the front cylinder head is defective, which limits the pressure of the device.
If you are technically skilled, you can dismantle the cylinder head yourself with a few simple steps and fit a new seal to restore functionality.
Furthermore, the center web of the cylinder head gasket, which is located between the intake and exhaust valves, may have a defect.
Notice: When it comes to compressed air, you should take certain safety precautions.