Gardner Denver VS-11, Руководство по эксплуатации и обслуживанию

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SECTION 1
GENERAL INFORMATION
Figure 1-1 – COMPRESSION CYCLE
COMPRESSOR – Your Gardner Denver Rotary Screw package is fitted with one (1) single stage, positive
displacement rotary compressor using meshing helical rotors to effect compression. Each pair of rotors is
supported between high capacity anti-friction bearings located outside the compression chamber. Single
cylindrical roller bearings are used at each end of the rotors to carry the radial loads. An additional
angular contact ball bearing is located at the discharge end of each rotor to carry axial thrust loads. The
main rotor sits next to its gate companion, in a side-by-side configuration.
COMPRESSION PRINCIPLE (Figure 1-1) - Compression is accomplished by the main and gate rotors
synchronously meshing in a one-piece cylinder. The main rotor has five (5) helical lobes, 72
°
apart,
which mesh with six (6) helical grooves, 60
°
apart, on its matching gate rotor.
The air inlet port is located on top of the compressor cylinder near the drive shaft end. The discharge port
is located near the bottom at the opposite end of the compressor cylinder.
Figure 1-1 is an inverted view
to show inlet and discharge ports . The compression cycle begins as the rotors unmesh at the inlet port
and air is drawn into the cavity between the main rotor lobes and gate rotor grooves (A). When the rotors
pass the inlet port cutoff, air is trapped in the interlobe cavity and flows axially with the meshing rotors (B).
As meshing continues, more of the main rotor lobe enters the gate rotor groove, normal volume is
reduced and pressure increases.
Oil is injected into the cylinder to remove the heat of compression and seal internal clearances. Volume
reduction and pressure continues to increase until the air/oil mixture trapped in the interlobe cavity by the
rotors passes the discharge port (C). Each rotor cavity follows the same “fill-compress-discharge” cycle in
rapid succession to produce a discharge flow of air that is continuous, smooth and shock free.
AIR FLOW IN THE COMPRESSOR SYSTEM (Figure 4-2, page 30) - Air enters the air filter and passes
through the inlet control (poppet) valve to the compressor inlet flange. After compression, the air/oil
mixture enters the oil reservoir where most of the entrained oil is removed by change of direction and
impingent. It is further removed by centrifugal action and drained down into the reservoir. The air and
remaining aerosols pass into a coalescing element where the oil is captured and drained through a drain
line back into a lower pressure region of the compressor. The nearly oil-free air passes through the
minimum pressure valve, aftercooler, moisture separator, and finally to the distribution network.
LUBRICATION, COOLING AND SEALING (Figure 4-2, page 30) - Oil is forced by differential pressure
from the oil reservoir through the oil cooler, servo-driven oil mixing valve, oil filter, and enters the
compressor. A portion of the oil is directed to internal passages within the compressor to lubricate the
bearings and shaft oil seals. The balance of the oil is injected into the compressor rotors to remove the
heat of compression, seal internal clearances and lubricate the rotors