About compressed air

1: What is the role of compressed air in air cushion systems?

For a correct functioning of air cushions, the air has to flow from a higher pressure to a lower one. So, it is necessary to use compressed air to make the system work. Instead of air, other means can be used.

2: What kind of air suppliers do I need to make the air cushion system work?

Compressed air is given in the S.I. unity : kPa. 100kPa = 1 bar (commonly used) = ~ 1 kg / cm² = ~ 15psi (lbs / Inch²).

Compressed air is usually supplied by a compressor or a pressure vessel. In some cases a blower can be used {pressure < 1 bar (100kPa )}.

In almost all cases, a higher supply pressure is better, because the diameter of hoses can be smaller and therefore easier to handle.

The compressor capacity is the amount of air supplied in normal litres per minute. (“Normal" in this case means the air being supplied at conditions of 20° C and 1 bar (100kPa). The power of the compressor should also correspond with the compressor rating. In practice, the pressure is around 7 bar (700 kPa).

Most compressors have a pressure vessel. Substantial savings can be encountered by using a large pressure vessel when the air film equipment is of short duty cycle. The air from the pressure vessel can be used to supply most of the air for the air cushion functioning.

The amount of air used by other installations in a factory plant can be very important. If a compressor supplies 5000Nl/mn and other installations are using 4000Nl/mn, a transport system that uses 2500Nl/in will give problems, if connected to the same air supply system.

3: What is the relation between air cushion pressure, floor demand and air consumption?

A higher air cushion pressure demands a higher floor quality and has higher air consumption per kg capacity. Therefore keep air cushion pressure as low as possible.