Emerson Copeland Screw SCA2, Руководство по применению

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AE4-1322
© 2002 Copeland Corporation
Issued 4-2002
Printed in U.S.A.
2
1 1
1 1 1 .
General General
General General General
This new series represents the result of further develop-
ment to provide a simplified and favorably priced screw
compressor for use in factory made systems.
Contrary to the semi-hermetic and open type, SHM/
SHL and SDM/SDL compressor models for commercial
and industrial installation, the compact screws are
designed with an integral oil separator. The effort
involved in installation is therefore comparable with that
for semi-hermetic reciprocating compressors.
In addition to this, the electrical control and the monitor-
ing of the oil circuit has been simplified. The proven
basic construction and the ease of service have been
retained.
The most modern screw compressor technology is now
available in the middle capacity range for compact liquid
chillers and air conditioning equipment.
2. Design and function 2. Design and function
2. Design and function 2. Design and function
2. Design and function
2.1 Design features
Copeland Compact screws are of the twin rotor design
with a newly-developed profile geometry (lobe ratio 5:6).
The main parts of these compressors are the two rotors
(male and female rotor), which are fitted into a closed
housing. The rotors are precisely located at both ends
in rolling contact bearings (radial and axial), which, in
conjunction with the generously sized oil supply
chambers, provides optimum emergency running
characteristics.
Owing to the specific design, this type of compressor
does not require any working valves. To protect against
reverse running when the compressor is switched off
(expansion operation) a check valve is incorporated in
the discharge chamber (this valve does not, however,
replace any check valves required by the system
design). An internal pressure relief valve is utilized for
over-pressure protection.
The compressor is driven by a three-phase asynchro-
nous motor, which is built into the compressor housing.
The motor rotor is located on the shaft of the male
screw rotor. Cooling is achieved by cold refrigerant
vapor, which mainly flows through bores in the motor
rotor.
The main technical features:
Balanced product range Balanced product range
Balanced product range Balanced product range Balanced product range
•
•
• •
• 8 basic models
• • • • • Tight performance graduation
Minimal space requirements and convenient Minimal space requirements and convenient
Minimal space requirements and convenient Minimal space requirements and convenient Minimal space requirements and convenient
piping design
piping design
piping design piping design
piping design
• Shortest installed length in its performance category
- shut-off valves / connections within compressor
dimensions
• Suction and discharge gas connections can be
rotated in 90° increments
• Terminal box accessible from top, wire access from
underneath
Universal applications Universal applications Universal applications Universal applications Universal applications
•••••
R134a, R407C and R22
•••••
R404A, R507A upon request
••••• With or without economizer
••••• Optimized R-134a version (SCA2)
New high-efficiency profile New high-efficiency profile
New high-efficiency profile New high-efficiency profile New high-efficiency profile
• Further developed geometry
• High rigidity
• Patented manufacturing process for highest
precision
• High tip speed to minimize blow-by
Double-walled, pressure-compensated rotor Double-walled, pressure-compensated rotor
Double-walled, pressure-compensated rotor Double-walled, pressure-compensated rotor Double-walled, pressure-compensated rotor
housing
housing
housing housing
housing
•••••
Extremely stable, therefore no expansion even at
high pressure levels
•••••
Additional sound attenuation
Proven, long-life bearings with pressure unloading Proven, long-life bearings with pressure unloading Proven, long-life bearings with pressure unloading Proven, long-life bearings with pressure unloading Proven, long-life bearings with pressure unloading
• Robust axial bearings in tandem configuration
• Bearing chamber pressure isolated by seal rings
• Pressure unloading of axial bearings
Optimized oil management Optimized oil management Optimized oil management Optimized oil management Optimized oil management
• Three-stage oil separator
• Long-life oil filter 10 µ mesh size
• Pressure relieved bearing chamber ensuring mini-
mum refrigerant dilution in the oil and thus higher
viscosity
Large volume motor for part winding or direct start Large volume motor for part winding or direct start Large volume motor for part winding or direct start Large volume motor for part winding or direct start Large volume motor for part winding or direct start
- optional star delta design
- optional star delta design - optional star delta design - optional star delta design - optional star delta design
• Especially high efficiency
Semi-hermetic compact screws Semi-hermetic compact screws
Semi-hermetic compact screws Semi-hermetic compact screws
Semi-hermetic compact screws
SCH2/SCA2 series
SCH2/SCA2 series SCH2/SCA2 series SCH2/SCA2 series SCH2/SCA2 series
35 to 140 HP Nominal motor power
35 to 140 HP Nominal motor power 35 to 140 HP Nominal motor power 35 to 140 HP Nominal motor power 35 to 140 HP Nominal motor power