Atlas Copco GA 30+, Instruction Book

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valve prevents the compressed air downstream the minimum pressure valve from being vented to
atmosphere during unloaded operation. When the compressor is stopped, inlet valve (IV) closes, preventing
compressed air (and oil) to be vented into the air filter.
Oil circuit
Flow diagram, oil circuit
Reference Description
1 Intake air
2 Air/oil mixture
3 Oil
4 Wet compressed air
Description
Air pressure in the separator tank forces the oil via oil filter (OF) to compressor element (E), where it acts
as sealant, coolant, lubricant and corrosion inhibitive (during stand still periods).
In air receiver/oil separator tank (AR), most of the oil is separated from the air/oil mixture by gravity and
inertia. The remaining oil is separated by oil separator (OS). The oil collects in the lower part of air
receiver/oil separator (AR).
The oil circuit is provided with a thermostatic bypass valve (BV). When the oil temperature is below its
setpoint, the oil cooler is bypassed. Bypass valve (BV) starts opening the supply to cooler (Co) when the
oil temperature has increased to the setpoint temperature. At approx. 15 ˚C (27 ˚F) above the setpoint
temperature, all the oil flows through the oil cooler.
A tropical thermostatic valve (available as an option) offers a higher opening temperature, it helps avoiding
condensate accumulation in the oil. This option is advised when the compressor operates in high humidity
conditions.
Instruction book
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