Comprag 14310000, Operating Manual

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11 COMPRAG RDX series compressed air refrigerated dryer
2.2 Function
RDX series compressed air refrigerating dryers are designed for removing condensate
from compressed air entering the compressed-air line from a compressor.
Air drying takes place by means of cooling the flow of compressed air to a temperature at
which water vapour, present in the compressed air, reaches saturation point (dew-point) and
turns from gaseous state to liquid. Condensate formed this way is extracted by the conden-
sate drain valve, which is actuated at set intervals on a time relay.
2.3 Functional description
2
1
9
6
5
8
7
3 4
AIR
REFRIGERANT
Fig. 2.1 Flow chart of compressed air dryer
1.Compressor
2.Evaporator
3.Condenser
4.Condenser fan
5.Refrigerant drying filter
6.Capillary tube
7.Hot gas bypass valve
8.Pressure relay of fan
9.Condensate drain valve
Compressor (1) injects hot refrigerant into condenser (3), where a large amount of the
refrigerant is turned into liquid form. The liquid refrigerant passes via the filter (5) into
the capillary tube (6). After passing through the capillary tube (6) and before entering the
evaporator (2), the pressure of the liquid refrigerant is lowered to boiling pressure with a
change from liquid to gaseous form.
The refrigerant in the evaporator (2) receives the heat
from the compressed air by means of heat exchange and fully changes to a gaseous state.