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KRSD series
2.2 THE COMPRESSION CYCLE
The compressor housing contains of two rotors; Male and
Female rotors. The male rotor has five lobes and female rotor
has six flutes. They are constantly and precisely meshed, and
housed in the cylinder with two parallel adjoining bores. All
parts are machined to exacting tolerances. The rotors provide
positive-displacement internal compression smoothly and
without surging. As the rotors rotate, air is drawn into the
cylinder through the inlet port. A volume of air is filled and
trapped as the rotor lobes pass the inlet port in the cylinders.
Compression occurs as the male rotor rolls into the female
flute, progressively reducing the space thereby raising the
pressure. Compression continues until the lobe and flute pass
the discharge port. The compressed air is then discharged into the air/oil separator tank.
There are five complete compression cycles for each complete rotation of the male rotor.
When the compressor is operating, a partial vacuum is produced at the compressor inlet.
Fluid is injected into the compressor unit and mixed with the air. The fluid has three basic
functions:
As a coolant, it controls the rise in air temperature normally associated with the heat
of compression.
It seals the leakage paths between the rotors and stator and also between the rotors
themselves.
It acts as a lubricating film between the rotors allowing one rotor to directly drive
the other, which is an idler.
After air/fluid mixture is discharged from compressor to the reservoir, fluid is separated
from the air in the separator tank. Compressed air then flows through the after-cooler for
moisture removal while the lubricant is being cooled by the fluid-cooler for re-injection.
