When the inlet/unloader valve is open, the air enters the compressor screw element. The screw element works like a pump and it compressed the air. During this process, oil is injected in the element. The oil is there to cool the air, as the air gets very hot during compression.
[pdf] Atlas Copco, Stockholm, Sweden, unveiled its latest generation of clean compressors at bauma 2019 — new sustainable mobile air equipment powered by lithium-ion batteries and energy-efficient electric motors.
[pdf] Heat generated during compression can cause air expansion before intake is completed. Poor cooling performance—whether due to inefficient oil cooling or water cooling —raises internal temperatures and reduces overall intake volume. Air displacement is directly proportional to rotor speed.
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