9 - 2
Basic Operation
General Description
The compressor is an oil flooded, positive displacement,
single stage, rotary screw compressor driven by a power
take-off from the transmission gearbox.
The compressor air receiver is constructed in accordance
with the appropriate standards for fusion welded pressure
vessels. It is fitted with a safety valve, automatic blowdown
valve, oil filter, separator and air delivery cocks.
The assembly is fully enclosed within a sheet metal body.
The plant is designed to be run with all panels closed except
for a door which enables the control panel to be observed.
Compressor Unit
The compressor unit consists of two helical intermeshing
rotors contained within the inlet/rotor casing, the male rotor
having four lobes and the female six flutes. Each rotor is
supported by a pair of combined journal and thrust ball
bearings at the delivery end and a roller bearing at the inlet
end. The combined journal and thrust bearings provide
accurate location of the rotors while the roller bearings
permit expansion of the rotors to take place freely and cater
for the radial loads at the inlet end. Fine clearances between
the end of the rotors and the casing at the delivery end of
the compressor unit are accurately maintained under all
conditions of operation.
The drive is transmitted from a power take-off on the
transmission gearbox via a drive shaft to the female rotor.
The helical engagement of the rotors transmits the drive to
the male rotor. The oil which is used as a cooling and
sealing medium also lubricates the bearings. The oil injected
on to the rotors provides a constant film of oil on them
preventing contact and wear. The resultant final air delivery
temperature is related to the ambient air temperature; refer
to Technical Data.
Compression Cycle
As the rotors revolve, air enters the compressor unit by way
of the air cleaner unloader and the inlet port, filling the space
between the lobes of the male rotor and the flutes of the
female rotor A. The air is carried around until a male lobe
intermeshes with a corresponding female flute. When the air
is trapped B compression commences and oil which is
being continuously injected mixes with the air C. Continued
rotation of the rotors reduces the volume of air/oil mixture
until it is compressed to outlet pressure D. At this point the
delivery port is uncovered and the mixture passes through
an adaptor and air delivery hose to the air/oil receiver. The
oil is separated from the air in the receiver and the air
passes to the delivery.
Section A Attachments
9803/7130
Section A
9 - 2
Issue 1
Airmaster Compressor
To Next Page
Loading...
Need help?
General
