Dunham-Bush WCFX-E Series, Руководство пользователя

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DISCHARGE
OIL DEFLECTOR
CAP
OIL STRAINER
MALE (DRIVE)
SUCTION
SUCTION
CHECK VALVE
MOTOR
1
ST
OIL SEPARATOR
REPLACEABLE
SUCTION FILTER
2
ND
OIL SEPARATOR
UNIT FEATURES
Compressor Assembly
The Dunham-Bush rotary screw compressor is a positive
displacement helical-axial design for use with high-
pressure refrigerants.
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The compressor consists of two intermeshing helical
grooved rotors, a female drive rotor and a male driven
rotor, in a stationary housing with suction and
discharge gas ports.
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Uniform gas flow, even torque and positive
displacement, all provided by pure rotary motion
contributes to vibration-free operation over a wide
range of operating conditions. Intake and discharge
cycles overlap, effectively producing a smooth,
continuous flow of gas.
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No oil pump is required for lubrication or sealing
purposes. Oil is distributed throughout the compressor
by the pressure differential between the suction and
the discharge cavities.
Simplified Capacity Control
The slide valve mechanism for capacity modulation and
part load operation is an outstanding feature:
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The moving parts are simple, rugged and trouble-free.
The slide mechanism is hydraulically actuated.
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Package capacity reduction can be down to as low as
8.5% without HGBP by progressive movement of slide
valves away from their stops.
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Capacity reduction is programmed by an exclusive
electronically initiated, hydraulically actuated control
arrangement.
Positive Displacement Direct Connected
The compressor is directly connected to the motor
without any complicated gear systems to speed up the
compressor and thus detract from the overall unit
reliability.
Oil Separation
Each compressor is provided with up to 2 integral oil
separator/impingement plate located below the discharge
gas port.
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The separator is a multi-layered mesh element which
effectively separates oil from the gas stream.
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The oil drains into the sump and the discharge gas
passes around the deflection plate. An oil drain valve
is located near the bottom of the oil sump.
Oil is also returned to the compressor after it is separated
from the refrigerant at the oil separator located at the
discharge of the compressor.
Main Bearings
Each rotor is fitted with a set of anti-friction tapered roller
bearings. They carry both radial and thrust loads. Anti-
reverse rotation bearings are used.
Rotors
The latest asymmetrical rotor profiles of patented
Dunham-Bush design assure operation at highest
efficiencies. Rotors are precision machined from high
strength alloy steel and precision ground, in house.
Castings
All housings are manufactured of high grade, low porosity
and cast iron.
Solid State Motor Protection
The motor winding protection module used in conjunction
with sensors embedded in the compressor motor
windings is designed to prevent the motor from operating
at unsafe operating temperatures. The overloads for the
motor are also solid state.