Atlas Copco GA 11+, Instruction Book

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Reference Description
A Air inlet
B Air/oil mixture
C Oil
D Wet compressed air
E Condensate
Air flow
Air comes in through filter (AF) and inlet valve (IV) and is compressed in the compressor element
(E).
A mixture of compressed air and oil flows into the air receiver/oil separator (AR), where oil and air
are separated.
The air flows through the minimum pressure valve (Vp), the air cooler (Ca) and the condensate
trap (MT) to the outlet valve (AV).
Minimum pressure valve (Vp) prevents the receiver pressure from dropping below a minimum
pressure and includes a check valve which prevents blow-back of compressed air from the net.
Units with integrated dryer have a dryer (DR) after the air cooler.
Oil circuit
The air receiver (AR) removes most of the oil from the air/oil mixture by centrifugal action. The oil
collects in the lower part of the air receiver (AR) which serves as oil tank.
The oil separator (OS) removes the remaining oil.
The oil circuit has a thermostatic bypass valve (BV) that prevents that the oil flows through the oil
cooler (Co) when the oil temperature is low.
Air pressure forces the oil from air receiver (AR) through the oil filter (OF).
The filtered oil flows back through the outlet housing and to the element.
Cooling on air-cooled compressors
The cooling system has an air cooler (Ca) and an oil cooler (Co) (see Flow diagram ).
The fan (FN) blows air over the coolers. This fan is set on and off, depending on the operating
conditions, according to a specific algorithm.
2.3 Condensate system
Drain connections
The compressors have an electronic water drain (LD200).
Instruction book
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