Frick SGXH-4021 - Page 33

070.650-IOM (JUL 19)
Page 33
SGC/SGX ROTARY SCREW COMPRESSOR
INSTALLATION
Single-acting mode - (> 150 psi pressure differential)
Open valve at SC1
Close valve at SC2
Open valve at BP (bypass)
Compressor Loading (Single-acting): The compressor loads
whenSVsolenoidYY2isenergizedandoilowsfromthe
unload side of the cylinder out port SC1, through valve ports
A and T to compressor suction. Simultaneously, discharge
pressure loads the slide valve.
Compressor Unloading (Single-acting): The compressor
unloadswhenSVsolenoidYY1isenergizedandoilowsfrom
the oil manifold through valve ports P and A to cylinder port
SC1 and enters the unload side of the cylinder. Simultane-
ously, gas on the load side of the cylinder is vented through
port SC2 and valve BP to compressor suction.
Notice
To control the rate of loading and unloading, throttle
the needle valve at SC1 port.
Double-acting mode - (< 150 psi pressure differential)
Open valve at SC1
Open valve at SC2
Close valve at BP (bypass)
Compressor Loading (Double-acting): The compressor
loadswhenSVsolenoidYY2isenergizedandoilowsfrom
the oil manifold through valve ports P and B to cylinder port
SC2 and enters the load side of the cylinder. Simultaneously,
oilcontainedin theunloadside of thecylinderowsout
cylinder port SC1 through valve ports A and T to compres-
sor suction.
Compressor Unloading (Double-acting): The compressor
unloads when SVsolenoidYY1isenergizedandoilows
from the oil manifold through valve ports P and A to cylinder
port SC1 and enters the unload side of the cylinder. Simulta-
neously,oilcontainedintheloadsideofthecylinderows
out of compressor port SC2 through valve ports B and T to
compressor suction.
Notice
To control the rate of loading and unloading, throttle
valves SC1 and SC2.
Notice
To slow all valve movements - loading, unloading, and
Vi change - throttle valve 2.
Caution
NEVER open valve BP and valve SC2 at the same time
during compressor operation.
Figure 28: Solenoid valve block
Figure 27: Hydraulic Schematic, SGC/SGX 4013, 4018, and 4021
DELETE (NC) FOR
BOOSTER
APPLICATIONS
DELETE (NC) FOR
BOOSTER
APPLICATIONS
SC1 SC1
UNLOAD
UNLOAD
VARIABLE VI
HYDRAULIC SCHEMATIC
FIXED VI
HYDRAULIC SCHEMATIC
INCREASE
LOAD
LOAD
120 V/1 PH/60 HZ
TYP
120 V/1 PH/60 HZ
TYP
DECREASE
3/8 OD SS
3/8 OD SS
3/8 OD SS
3/8 OD SS
FROM AIR SUPPLY
FROM AIR SUPPLY
CYLINDER OIL SUPPLY
CYLINDER OIL SUPPLY
SC1 SC1
YV
1541
YV
1541
YV
1541
YV
1541
YV
1542
YV
1542
YV
1543
YV
1544
YV
1542
YV
1542
SC2
BP
BP
SC2
A1
A1
0S
0S
SC3
SC3
T1
SC2 SC2
NC NCNC NC
SC3 SC3
T1
DELETE (NC) FOR
HIGH STAGE
APPLICATIONS
DELETE (NC) FOR
HIGH STAGE
APPLICATIONS
SC5
SC5