VACUUM PUMPS AND AIR COMPRESSORS

An air receiver is essential to every compressed air system to act as a buffer and a storage medium between the compressor and the consumption system. There are in principal two different air receivers in a compressed air system:

• PRIMARY receiver - located near the compressor, after the after-cooler but before filtration and drying equipment

• SECONDARY receivers - located close to points of larger intermittent air consumptions

The maximum capacity of the compressor in a well designed systems always exceed the maximum mean air consumption of the system (maximum mean air consumption is the mean air consumption over some reasonable time).

Since the maximum capacity of an air compressor also always exceed the minimum air consumption in the system - the compressor must modulate its capacity during normal work, often by using primitive strategies as on/off modulating or more advanced strategies as frequency drives and inverters. Primitive modulating strategies cause more pressure variations in compressed air systems than more advanced strategies.

In addition, the air consumption vary due to the process supported. In shorter periods the demand for compressed air may even exceed the maximum capacity of the compressor. In fact, it is common in well designed systems not to design the compressor for the maximum peek loads.

Air receivers in compressed air systems serves the important purposes of

• equalizing the pressure variation from the start/stop and modulating sequence of the compressor

• storage of air volume equalizing the variation in consumption and demand from the system

• In addition the receiver serve the purpose of

• collecting condensate and water in the air after the compressor