070.250-IOM (APR 11)
Page 17
408 MM ROTARY SCREW COMPRESSOR
OPERATION
LOW AMBIENT OPERATION
It is recommended that package oil separators be insulated
as a minimum requirement to preserve the heat generated
by the oil heaters, to prevent condensation and secure
lubrication at start-up.
INITIAL START-UP
Prior to the start-up, the prestart check must be
accomplished.
INITIAL START-UP PROCEDURE
Having performed the prestart check, the compressor unit
is ready for start-up. It is important that an adequate gas
load be available to load test the unit at normal operating
conditions. The following points should be kept in mind
during initial start-up.
1. For proper and safe operation, the compressor must be
run at the proper speed and discharge pressure. Exceeding
design conditions creates a potential hazard.
2. After 1 to 3 hours of operation adjust oil cooling system.
3. Pull and clean suction strainer after 24 hours of
operation. If it is excessively dirty, repeat every 24 hours
until system is clean. Otherwise, follow the normal
maintenance schedule.
4. Perform vibration analysis if equipment is available.
Figure 11 - Hydraulic Schematic
SC4
BP
SC2
SC3
SC1
SC3
2
SC4
SC3
SC13
1
2
SC2
SC1
2
SC2
1
1
2
A
B
1
P
T
BP
B
A
T
P
SC1
SV-3
T
HYDRAULIC SCHEMATIC
408 MM
P
SV-2
SCREW IN FLOW
REGULATING
NEEDLE VALVE
DIRECTION
CONTROL
VALVE
CUSTOMER
SUPPLIED
PUMP
DIRECTION
CONTROL
VALVE
SP-1
YY2 (LOAD)
YY4 (DECREASE VI)
COMPRESSOR
TOP VIEW
YY1
YY2
YY3
YY4
(UNLOAD) YY1
(INCREASE VI) YY3
SC3
2
1
NORMAL START-UP PROCEDURE
1. Confirm system conditions permit starting the
compressor.
2. Start.
3. Observe the compressor unit for mechanical tightness
of the external piping, bolts and valves. Ensure that the
machine has no oil and vapor leaks. If any of these occur,
shut down the compressor and correct the problem as
necessary using good safety precautions.
