Compressor Technology - Sweb.cz

Air quantity
The compressor produces a specific flow (capacity), air quantity or volume/time. The capacity is
usually presented in m³/min, l/min or l/s and states at what pressure it was measured. The value is
called Free Air Delivery (FAD) (Example, ACB 10-270 gives 970 l/min FAD at 6.3 bar.) The measurement
standard used is ISO 1217.
Air pressure
The compressed air is compressed to a given maximum pressure, generally from 8 to 10 bar. (Higher pressures
can occur.) The pressure at each point of use is adjusted by means of a regulator and is determined
by the application. Producers of air tools, air motors, paint sprayers and pneumatics normally state at what
pressure their products should be used. Examples of required operating pressure for different applications:
• Ordinary cleaning/blowgun, about 6–8 bar
• Ordinary air motors, grinding machines, impact wrenches, about 6–7 bar
• Paint sprayers, about 2–4 bar
• Pneumatics, cylinders, typically 5-7 bar
Air Quality
Compressed air is used in everything from workshops to laboratory environments and
consequently the demands on compressed air quality differ. Typical criteria considered are:
• Water/oil content • Particle content
• Sterility • Odour/taste
Large compressor installations are usually equipped with post-treatment of the
compressed air to conform to the different needs.
Airflow
To get the most out of your compressor, you should always think about the airflow that you will need.
Hose size, length and the type of hose to be used have a far-reaching effect on the result.
Example:a straight hose with an inside diameter of 6 mm and a length of 3 metres can give 360 l/min. The
same hose in a longer design, for example 10 metres, only gives 200 l/min. If, however, you choose a straight
hose with an inside diameter of 9 mm and a length of 10 metres, the flow in the hose can reach 535 l/min.
When using 3”– 4” nail guns, you should therefore select a hose that has an inside diameter of at least
9 mm in order to be sure that the tool can perform the work. Large compressor installations are usually
equipped with post-treatment of the compressed air to conform to the different needs.
Ø Dim Length Capacity l/m
meter Straight Rolled
¼"– 6 mm 3 360
10 200
50 108 100
⅜" 10 535 510
50 300 285
½" 10 805 700
10